• 제어로봇시스템학회논문지
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• 제22권9호
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• pp.686-692
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• 2016

A Crimp Force Monitor (CFM) is equipment for detecting crimp errors by analyzing crimp signals obtained from force and strain sensors. The analysis is commonly performed by aligning a measured crimp signal with a reference signal and comparing their difference. Current analysis methods often suffer from wrong alignments that result in false negative detections. This paper presents a new crimp signal analysis method in CFM. First, a falling edge alignment is proposed that matches falling edges of the measured and the reference signals by minimizing the absolute difference summation. Second, a signal parameter error is introduced to evaluate the crimp quality difference between the measured signal and the reference. For calculating the signal parameter error, part of a signal is identified and divided into several regions to maximize the signal parameter errors. Experiments showed that the proposed method can improve the signal alignment and accurately detect bad crimps especially with the strain sensor.

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2008년도 제39차 학술발표회
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• pp.137-138
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• 2008

Viscose rayon is not a thermoplastic yarns, but it was deformed with the heat in this study. Therefore, bulky rayon yarn was developed by modifying the shrinkage for rayon and reviling the micro crimp of the rayon, and finally, span knit was developed with bulky rayon yarns.

• 한국염색가공학회지
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• 제20권1호
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• pp.36-43
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• 2008

False twist texturing uses the thermoplastic property of synthetic yarn and produces a bulk and a stretch by giving the filament a permanent crimp. This study investigated the effects of false twist texturing parameters, disk/yarn(D/Y) and heater temperature, on the physical properties of nylon textured yarn. D/Y was a primary determinant of twist numbers of filaments and was proportionally increased with the twist numbers of filaments, resulting in an increase of crimp rigidity of the textured yarn. Heater temperature, a determinant of the heat setting of transformed filaments, was proportionally increased with the increase of crimp rigidity. Nylon 6 was partially melted at $190^{\circ}C$. This study consequently suggested the optimal parameters of nylon 6 85d/68f full-dull POY.

• 한국의류산업학회지
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• 제1권4호
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• pp.387-392
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• 1999

The effects of the ratio of warp diameter to filling diameter (${\beta}$-ratio) and warp thread crash on the crimp factor and the yarn curvature were studied theoretically in this paper. The models of 2/2 twill fabric derived square cloth and sinusoidal curved cloth were used for the theoretical analysis. The crimp factors (C) for the models were given theoretically as follows; (1) Derived square cloth(general equation for b) $$C=\frac{(1+{\beta})({\theta}-sin{\theta})}{(1+{\beta})sin{\theta}+{\alpha}}$$ (2) Sihusoidal curved cloth $$C=\frac{(1+{\beta})sin{\theta}\[1+\{\frac{{\pi}(1-cos{\theta})}{4sin{\theta}}\}^2\]+{\alpha}}{(1+{\beta})sin{\theta}+{\alpha}}-1$$ The curvatures(${\kappa}$) for the models were given theoretically as follows; (1) Derived square cloth $${\kappa}=\frac{2}{d_w+d_f}$$ (2) Sinusoidal curved cloth $${\kappa}=\|{^{\;\;\prime\prime} \atop r}(s)\| \\ where \;s=\frac{p^'}{{\pi}}\(u+\frac{k^2u}{4}+\frac{k^2}{8}sin2u\)$$.

• Fibers and Polymers
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• 제6권1호
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• pp.55-65
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• 2005

Extensible elastica solutions of two-dimensional deflection of crimped fiber cantilever of circular wavy crimp were obtained for one end clamped boundary under concentrated, inclined and dead tip load Fiber was also regarded as a linear elastic material. Crimp was described as a combination of semicircular arcs smoothly connected with each other having con­stant curvature of all the same magnitude and alternative sign. Also the inclined load direction was taken into account. The solutions were expressed as the recursive forms of integrals in two different cases, which can also be transformed to elliptic integrals respectively. Comparing the data with inextensible ones was carried out. Consequently in the solution, the normal strain of neutral axis is expressed in terms of cross-sectional area, second moment of area and normalized load parameter. Examples of the circular cross-sectioned fiber are presented. As a result, the differences of normalized load between inexten­sible and extensible elastica solutions when the radius ratio becomes 0.1 were maximum $\Lambda$ = 0.1.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 춘계학술발표대회 논문집
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• pp.154-157
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• 2005

This paper aims to investigate the tow deformation pattern with respect to shear angle and mold property during draping of plain weave carbon/epoxy prepreg. Aluminum and PVC foams with different foam density are used for the draping hemisphere molds with 250 mm diameters. Microscopic observation reveals that tow parameters like crimp angle and Y-directional tow intervals are influenced by shear angle and mold density at the same time. The correlation between crimp angle and Y-directional tow interval is also found out.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 1999년도 봄 학술발표회 논문집(I)
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• pp.319-324
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• 1999

This study is to investigate the properties on the load-deflection and fracture behaviors of the steel fiber reinforced concrete(SFRC) slab model specimens, Steel fibers of indent, crimp, and end hook shape were considered to reinforce the matrix under various mixing conditions and proportions. Initial cracking load, maximum load, and energy absorption capacity(load carrying capacity) of SFRC panel specimen increased with increase of steel fiber contents. And the plain concrete slab was fractured abruptly after maximum load but SRFC slabs were fractured smoothly by steel fibers in concrete matrix operated as cracking resistance force after maximum load. Indent, crimp and end hook shape steel fibers were effective in reinforcing the matrices but end hook type fiber were superior to indent and crimp type fibers.

• 한국임상수의학회:학술대회논문집
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• 한국임상수의학회 2008년도 춘계학술대회
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• pp.89-89
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• 2008

• 한국염색가공학회:학술대회논문집
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• 한국염색가공학회 2011년도 제45차 학술발표회
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• pp.28-28
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• 2011

최근 초경량 직물에 나일론 Spiral Crimp 신축소재에 많이 사용되어지는 Mechanical 신축성 직물이 시판되고 있으나 신축특성의 저하, 품질 저하의 문제점이 대두되고 있어 아직까지 본격적으로는 상용화되지 못하고 있고 국내외적으로 아직까지 나일론 세섬사 Spiral Crimp 신축소재개발과 관련된 기술개발은 전무한 실정이다. 따라서 본 연구에서는 현재까지 국내외적으로 개발되지 못한 스포츠 아웃도어용 경량직물의 Mechanical 신축성 초경량 직물을 개발하기 위해서 중합단계에서 나일론 개질 폴리머를 개발하고, 수축 특성이 서로 다른 2종의 나일론 폴리머를 이용하여 side by side 형태로 세섬 복합방사와 사가공 및 연신 단계에서 2d급 Spiral Crimp 및 Super Bulky특성이 우수한 신축성 소재를 개발하여 이들의 구조와 물성을 조사 검토하여 이를 실제 현장에 자료를 제공하는 것을 목적으로 하였다.

• Composites Research
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• 제29권1호
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• pp.33-39
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• 2016

본 논문에서는 3차원 평직 복합재료의 3-방향 섬유다발의 굴곡각에 따른 다양한 모델링을 구축하고, 제시한 모델에 대하여 등가 물성치를 예측하였다. 3차원 평직복합재료의 단위셀을 정의하고 미시역학 계산결과인 섬유다발 물성치를 사용하여 섬유다발에 굴곡각에 따라 물성치가 변화하도록 요소 물성축을 설정 후 3차원 평직 복합재료의 중시해석을 수행하였다. 계산결과 등가물성치는 참고문헌에 제시된 해석 및 실험값을 비교하여 타당성을 확보하였으며 계산결과 3-방향 섬유다발 굴곡각이 미치는 영향에 대하여 고찰하였다. 또한 초기파손 강도와 파손순서에 대해서도 조사하였다.