• Title/Summary/Keyword: fabric structures

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Antimicrobial Activity of Fabrics Treated with Colloidal Silver Solutions Made by Electrolysis and Reduction (제조 방법이 다른 은 콜로이드 용액 처리 직물의 항균효과)

  • Chung Haewon;Kim Boyeon;Yang Heeju
    • Journal of the Korean Society of Clothing and Textiles
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    • v.29 no.6
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    • pp.805-813
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    • 2005
  • In recent years, greatly increased incidences of diseases made people more concerned about their hygienic environment. Since clothes are the closest environment to man, many methods have beef proposed to impart antimicrobial properties to the textiles. Benefits associated with incorporating antimicrobial properties in textiles include protection to the wearer from microbiological attack, and prevention of odor from perspiration. Silver has been known to kill 650 different disease organisms, however, nano-sized silver particles are known as skin friendly and does not cause skin irritation. In this study, we have examined the antimicrobial effects of cotton or polyester fabric, on which nano-sized silver particles were treated. Colloidal silver solution made by electrolysis of $99.9\%$ silver stick was more effective than that by reduction of $AgNO_3.\;0.7\%$ concentration of colloidal silver solution by electrolysis is helpful to give reduction of $99.9\%$ S. aureus and K. pneumoniae on a cotton fabric without the decrease of whiteness. Since the structures of fiber and fabric effect on their antimicrobial property, PET filament fabric didn't have sufficient antimicrobial properly. The fabrics treated with up to $5\%$ colloidal silver solution didn't have the properly of antistatic and electromagnetic shield.

Permeability prediction of plain woven fabric by using control volume finite element method (검사체적 방법을 이용한 평직의 투과율 계수 예측)

  • Y. S. Song;J. R. Youn
    • 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.

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Experimental Study on Bank Protection System using Fabric Foam (친환경 섬유대공 하천호안공법의 현장계측 연구)

  • Kim, Jin-Man;Cho, Sam-Deok;Choi, Bong-Hyuck;Kwak, Ki-Seok;Woo, Hyo-Seop;Ahn, Hong-Kyu
    • Journal of the Korean Geosynthetics Society
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    • v.3 no.2
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    • pp.3-11
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    • 2004
  • Fabric Foam systems provide a variety of flexible bank protection for open channels and hydrulic structures. The structural performance and durability of conventional bank protection materials such as concrete, gravel, riprap and vegetation can be significantly improved by confining the materials within the cells of Fabric Foam system. This paper presents the results of field and laboratory tests carried out to evaluate the performance of new Fabric Foam System as a Bank Protection. The results of the tests confirmed effect of Fabric Foam System in Bank Protection.

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A Study on Improving the Fatigue Life for a Woven Glass Fabric/Epoxy Laminate Composite Applied to Railway Vehicles (철도차량용 직물 유리섬유/에폭시 적층 복합재의 피로수명 향상 방안 연구)

  • Ko, Hee-Young;Shin, Kwang-Bok;Kim, Jung-Seok
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.34 no.2
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    • pp.203-209
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    • 2010
  • In this study, the fatigue characteristics and life of a woven glass fabric/epoxy laminate composite applied to railway vehicles was evaluated. The fatigue test was conducted using a tension-tension load with a stress ratio R of 0.1 and frequency of 5 Hz. Two types of woven glass fabric/epoxy laminate composite was used in the fatigue test: with and without carbon/epoxy ply reinforcement. In addition, the fatigue life of the woven glass fabric/epoxy laminate composite was compared with that of aluminum 6005, which is used in the car body and underframe structures of railway vehicles. The test results showed that the failure strength and life of the woven glass fabric/epoxy laminate composite reinforced with three carbon/epoxy plies had a remarkable improvement compared with that of the bare specimen without reinforcement.

Design of Switching Fabric Supporting Variable Length Packets (가변 길이 패킷을 지원하는 스위칭 패브릭의 설계)

  • Ryu, Kyoung-Sook;Kim, Mu-Sung;Choe, Byeong-Seog
    • Journal of KIISE:Computing Practices and Letters
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    • v.14 no.3
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    • pp.311-315
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    • 2008
  • The switching fabric used to make high speed switching for packet transfer between input and output interface in recent internet environments. Without making any changes in order to remain ATM switching fabric, the existing structures should split/reassemble a packet to certain size, set aside cross-point buffer and will put loads on the system. In this paper, we proposed a new switch architecture, which has separated data memory plane and switching plane packet data will be stored on the separate memory structure and simultaneously only the part of the memory address pointers can pass the switching fabric. The small mini packets which have address pointer and basic information would be passed through the switching fabric. It is possible to achieve the remarkable switching performance than other switch fabrics with contending variable length packets.

Computational analysis of sandwich shield with free boundary inserted fabric at hypervelocity impact (비구속 삽입된 직물 섬유를 이용한 샌드위치 쉴드의 초고속 충격 해석)

  • Moon, Jin-Bum;Park, Yu-Rim;Son, Gil-Sang;Kim, Chun-Gon
    • Composites Research
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    • v.24 no.3
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    • pp.31-38
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    • 2011
  • In this paper, a novel hybrid composite shield to protect space structures from hypervelocity impact of micrometeoroid and space debris is proposed. The finite element model of the proposed shield was constructed and finite element analysis was conducted to approximate the energy absorption rate. Before the final model analysis, analysis of each component including the aluminum plate, PMMA plate, and intermediate layer of fabric was performed, verifying the finite element model of each component. The material properties used in the analyses were predicted material property values for high strain rates. The analysis results showed that, other than the fabric, the energy absorption rate of each component was in agreement. Afterwards, the finite element model of the hybrid composite shield was constructed, where it was analyzed for the restrained and unrestrained fabric boundary condition cases. Through the finite element analysis, the fiber pullout mechanism was realized for the hybrid shield with free boundary inserted fabric, and it was observed that this mechanism led to energy absorption increase.

Effect of Fabric Design Condition on the Mechanical Properties and Handle of Nylon/Cotton Union Fabrics for Sport Jacket (스포츠쟈켓용 나일론/면 교직물의 설계조건에 따른 역학적 특성과 태)

  • Kwon, Oh-Kyung;Song, Min-Kyu
    • Fashion & Textile Research Journal
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    • v.5 no.3
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    • pp.267-272
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    • 2003
  • Tactel(Nylon66) union fabrics were woven with the specification of 70d/34f nylon as warp for sport wear jacket. Weft yarn has three types; 100% cotton yarn, nylon core-spun yarn and nylon-polyurethane covering yarn as weft. Fabric structers were plain, twill and satin weave structure with the air jet loom. The mechanical properties of 8 fabrics were measured with KES-F and primary Hand Values and Total Hand Values were calculated. The results of the study were as follows: 1) There was little difference among LTs of N/CM fabric groups. RT of the fabrics with CM100's was bigger than that of fabrics with CM80's, resulting that the fabrics with CM100's have better formability. In terms of weaving structure, twill fabrics have shape deformation. 2) In comparison of RTs with weft yarn type, RT of N-PU covering yarn was the highest, followed by Nylon core-spun yarn and cotton yarn. Thus, the fabric with N-PU covering yarn has better stability of shape deformation. 3) Stretch yarn could express an excellent silhouette formation and twill and satin structures were better structure to make curvature on human form. 4) 2HG/G value of nylon core-spun fabrics was larger than that of N/C fabrics, but the silhouette formation of N/C fabrics was excellent. 5) The RC of N/PU was the highest, followed by N/P, and N/CM. 6) Koski of N/PU fabrics was the highest, Numeri of N/PU and N/Co-I were relatively higher than the others. THVs of N/CM-IV and N/CO-II were lower than the others, resulting that, twill structure was better than plain structure for a sport wear uses.

A Study on the Cutting Pattern Determination for Fabric Structures (막 구조물의 재단 패턴 결정에 관한 연구)

  • Choi, Ho;Lee, Jang-Bog;Kim, Jae-Yeol;Sur, Sam-Uel;Kwon, Taek-Jin
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 1998.10a
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    • pp.266-273
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    • 1998
  • The object of this study is shape finding and cutting pattern generation of membrane structures under the following assumptions: (1) material is linearly elastic (2) stress state is plane stress. Cable and membrane structures should introduce the nonlinear analysis considering geometric nonlinearity because these structures deform largely under the external loads. The analysis procedure is consisted of three steps considering geometric nonlinearity unlike any other structures. First step is the shape finding analysis to determine the initial equilibrium shape. Second step is the stress-deformation analysis to investigate the behaviors of structures under various external loads. Once a satisfactory shape has been found, a cutting pattern based on the shape finding analysis may be generated from the view point of construction. In this paper, after shape finding analysis, cutting pattern determination procedure using weighted least-square minimization flattening method and some results are presented.

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A Study on Electromagnetic Wave Absorbing Sandwich Structures (샌드위치 구조를 갖는 전자기파 흡수체에 관한 연구)

  • Park, Ki-Yeon;Lee, Sang-Eui;Kim, Chun-Gon;Lee, In;Han, Jae-Hung
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.32 no.6
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    • pp.64-71
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    • 2004
  • The object of this study is to design the Radar Absorbing Structures (RAS) having sandwich structures in the X-band ($8.2{\sim}12.4GHz$) frequencies. Glass fabric/epoxy composites containing conductive carbon blacks and carbon fabric/epoxy composites were used for the face sheets. Polyurethane(PU) foams containing multi-walled carbon nanotube (MWNT) were used for the core. Their permittivities in the X-band were measured using the transmission line technique. The reflection loss characteristics for multi-layered sandwich structures were calculated using the theory of transmission and reflection in a multi-layered medium. Three kinds of specimens were fabricated and their reflection losses in the X-band were measured using the free space technique. Experimental results were in good agreements with simulated ones in 10dB absorbing bandwidth.

Analysis of Image Similarity Index of Woven Fabrics and Virtual Fabrics - Application of Textile Design CAD System and Shuttle Loom - (직물과 가상소재의 화상 유사성 분석 연구 - 수직기 및 텍스타일 CAD시스템 활용 -)

  • Yoon, Jung-Won;Kim, Jong-Jun
    • Fashion & Textile Research Journal
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    • v.15 no.6
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    • pp.1010-1017
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    • 2013
  • Current global textiles and fashion industries have gradually shifted focus to high value-added, high sensibility, and multi-functional products based on new human-friendliness and sustainable growth technologies. Textile design CAD systems have been developed in conjunction with computer hardware and software sector advances. This study compares the patterns or images of actual woven fabrics and virtual fabrics prepared with a textile design CAD system. In this study, several weave structures (such as fancy yarn weave and patterns) were prepared with a shuttle loom. The woven textile images were taken using a CCD camera. The same weave structure data and yarn data were fed into a textile design CAD system in order to simulate fabric images as similarly as possible. Similarity Index analysis methods allowed for an analysis of the index between the actual fabric specimen and the simulated image of the corresponding fabric. The results showed that repeated small pattern weaves provide superior similarity index values than those of a fancy yarn weave that indicate some irregularities due to fancy yarn attributes. A Complex Wavelet Structural Similarity(CW-SSIM) index resulted in a better index than other methods such as Multi-Scale(MS) SSIM, and Feature Similarity(FS) SSIM, across fabric specimen images. A correlation analysis of the similarity index based on an image analysis and a similarity evaluation by panel members was also implemented.