• Proceedings of the Korean Society For Composite Materials Conference
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• 2002.05a
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• pp.181-183
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• 2002

The accurate permeability for preform is critical to model and design the impregnation of fluid resin in the composite manufacturing process. In this study, the in-plane and transverse permeability for a woven fabric are predicted numerically through the coupled flow model which combines microscopic with macroscopic flow. The microscopic and macroscopic flow which are flows within the micro-unit and macro-unit cell, respectively, are calculated by using 3-D CVFEM(control volume finite element method). To avoid checker-board pressure field and improve the efficiency on numerical computation, A new interpolation function for velocity is proposed on the basis of analytic solutions. The permeability of plain woven fabric is measured through unidirectional flow experiment and compared with the permeability calculated numerically. Based on the good agreement of the results, the relationships between the permeability and the structures of preform such as the fiber volume fraction and stacking effect can be understood. The reverse and the simple stacking are taken in account. Unlike past literatures, this study is based on more realistic unit cell and the improved prediction of permeability can be achieved. It is observed that in-plane flow is more dominant than transverse flow in the real flow through preform and the stacking effect of multi-layered preform is negligible. Consequently, the proposed coupled flow model can be applied to modeling of real composite materials processing.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.21 no.11
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• pp.1757-1764
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• 1997

The geometric and elastic models based on the unit cell have been proposed to predict the geometric characteristics and the engineering constants of plain and satin woven composites. In the geometric model, length and inclined angle of the yarn crimp and the fiber volume fraction of woven composites have been predicted. In the elastic model, the coordinate transformation has been utilized to transform the elastic constants of the yarn crimp to those of woven composites, and the effective elastic constants have been determined from the volume averaging of the constituent materials. Good correlations between the model predictions and the experimental results of carbon/epoxy and glass/epoxy woven composites have been observed. Based on the model, the effect of various geometric parameters and materials on the three-dimensional elastic properties of woven composites can be identified.

• Fashion & Textile Research Journal
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• v.9 no.2
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• pp.243-248
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• 2007

This study is about the fabric attached to the relics excavated from the Shimchun-ri tomb of the 4th century and the Moonsan-ri tombs of the 5th century. We studied 5 pieces of fabric from the Shimchun-ri tomb: one piece was silk and the other four pieces were hemp. We were able to observe 8 pieces from the four tombs in Moonsan-ri, All of them except one ramie were silk. The two kinds of bast fiber found in the tombs of Shimchun-ri and Moonsan-ri were hemp and ramie, and they were found to be plain woven with S-twist thread which thickness is uneven. The density was more fine compared to the hemps found in the Kaya or Shinra tombs of the similar era. All of the silk textiles found in the Shimchun-ri and Moonsan-ri tombs used non-twisted thread, and were plain woven. Also, we found degummed and raw silk from the tombs. The average density of the silk textiles from these tombs are similar to other areas of the same time, and studies show that they used non-twisted thread in plain woven silk found in other tombs. Therefore, we can conclude that they usually used non-twisted thread when producing silk textiles.

• Journal of the Korean Home Economics Association
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• v.25 no.1
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• pp.11-18
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• 1987

The purpose of this study was to investigate the crease recovery and the elastic recovery as a function of the direction of plain woven fabrics. The crease recovery was measured by Mosanto's Method and the elastic recovery was investigated by Autograph for ten kinds of plain woven fabric samples. The results were as follows; 1. Values of crease recovery were in the order of bias>weft>warp. 2. The lengthening of recovery time had a little effect on crease recovery. 3. The directions of crease recovery were affected by that of thread twist. 4. The linearity was shown between total crease recovery and warp-weft crease recovery. 5. The linearity was found between crease recovery and elastic recovery in the fabrics.

• Journal of the Korean Society of Safety
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• v.19 no.1
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• pp.31-37
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• 2004

The mechanical strength and crack propagation of plain woven carbon fiber fabric laminate composites are examined by acoustic emission(AE). AE signals are measured during the tensile test and fracture tests. Thus, the relationship between AE signal and load-displacement curves and crack extension length are shown. Also the fracture mechanisms in terms of AE characteristics are discussed in viewpoint of crack propagation behavior.

• Journal of Power System Engineering
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• v.10 no.2
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• pp.117-123
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• 2006

Woven fabrics composites are used as primary structural components in many applications because of their superior properties that offer high specific strength and stiffness. However, the complexity of the fabric structure makes understanding of their failure behavior very difficult. Also, laminate woven fabrics CFRP have unique failure mechanisms such as fiber bridging, fiber/matrix crack and so on. In particular, the delamination phenomenon of the composite materials is one of the most frequent failure mechanisms. So, we estimated interlaminar fracture and damage in composites using as ENF specimen by a 3 point bending test. And AE characteristics were examined for crack propagation on plain woven CFRP. We obtained the following conclusions from the results of the evaluation of the 3 point bending fracture test and AE characteristic estimation. AE counts of maximum crack length were obtained as $85.97{\times}10^4\;and\;93{\times}10^3\;for\;a_0/L=0.3$ and 0.6, respectively. Also the maximum amplitudes were over 80dB at both $a_0/L=0.3\;and\;0.6$. $G_{IIc}$ at that's $a_0/L$ ratio were obtained with $1.07kJ/m^2\;and\;3.79kJ/m^2$.

• Fibers and Polymers
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• v.5 no.1
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• pp.6-11
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• 2004

The purpose of this study is to analyze the subjective fabric hand of sleepwear fabrics, and to assist in developing sleepwear fabrics that offer maximum comfort in wearing sensation. In general, the respondents noted that sleepwear fabrics made with polyester had better tactile sensation than those made with cotton, while satin weave fabrics felt better than plain weave fabrics. As regards the difference in fabric hand according to gender, female students responded with more receptiveness and sensitivity than male students in the category of woven fabric evaluation. As regards the same textile materials, the evaluations of female students and male students differed in fabric hand descriptors, particularly for the evaluation on cotton fabrics. Male students responded that both plain weave fabrics and satin weave fabrics were stiff while female students replied that satin weave fabrics had better tactile sensation.

• Journal of the Korean Society of Costume
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• v.62 no.7
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• pp.41-53
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• 2012

Hwangnamdaechong Tomb (The 98th tomb in Hwangnam-dong), one of the royal tombs located around the area of royal tomb of King Michu in Hwangnam-dong, Gyeongju, is currently designated as Historic Site No. 40. It is assumed that Hwangnamdaechong Tomb is a royal tomb of the early 5th century. This study aims to examine the fabric relics excavated from Hwangdamdawchong Tomb and currently housed in Gyeongju National Research Institute of Cultural Heritage. The types of fabrics excavated from Hwangdamdawchong Tomb include plain silk, warp-faced compound woven silk, and hemp cloth. Most of these fabrics are adhered to metal products that became rusty. Plain silk found in Hwangnamdaechong Tomb can be divided into four types by its weaving method. Geum excavated from Hwangnamdaechong Tomb is typical Gyeong Geum that uses colored warp for its base and pattern. It is plain Gyeong Geum that the binding weft and warp is plain woven. Although there are a lot of Gyeong Geum fabrics whose colors are hard to define due to yellowing after long years, there are still many fabrics whose color such as purple, red, blue, and green can be identified. As literatures have shown that p cloth as well as silk were frequently woven during Silla dynasty, tremendous amount of hemp cloth was excavated. Most of the hemp cloth has S-twist in the warp and 8-12 seung degree of delicacy.

• Textile Coloration and Finishing
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• v.12 no.3
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• pp.159-165
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• 2000

This study surveys the fabric mechanical properties according to the weaving design & finishing conditions of wool fabrics for quality control in the process. For this purpose, 8 kinds of Twill groups and 3 kinds of Plain groups weave fabrics, totally 428 woven fabrics are prepared with change of the yarn count, density and finishing method. Fabric thickness, bending rigidity, extensibility, shear rigidity, formability of the fabrics were measured and discussed with weaving design & finishing conditions.

• Journal of Fashion Business
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• v.10 no.6
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• pp.28-37
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• 2006

The purpose of this work is to present three-dimensional models of plain fabrics having various warp and filling yarn diameters. In order to simulate a woven fabric, a 3-dimensional CAD software with NURBS modeling capability was used. Final rendering was performed on the fabric model. It was demonstrated that the changes in yarn diameter could be three-dimensionally modeled through the use of fabric geometry and the 3D CAD. A short RhinoScript program was composed to implement the data importing and model building on the 3D CAD.