• Composites Research
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• v.23 no.6
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• pp.19-25
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• 2010

This paper describes the optimum design of bolt locations for metal joint parts of railway bogie frame made of glass fiber/epoxy 4-harness satin woven laminate composite and PVC foam core. The optimum design analysis was done by sub-problem approximation method using Ansys Parameter Design Language(APDL). The sub-modeling method was introduced to conduct the detailed recalculation for the only target parts and reduce calculating time. The structural analysis for composite bogie frame was performed according to JIS E 4207. The results showed that the optimum design analysis using sub-modeling method was able to obtain faster and more precise results than that of the entire model by the control of mesh size for the target parts, and the maximum Von-Mises stress has been reduced in comparison with its original dimensions due to the optimum design of bolt locations.

• Journal of Fashion Business
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• v.19 no.5
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• pp.1-16
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• 2015

The appearances and geometry structures of knitted fabrics have important effects on their functions as textile fabrics. Structural design of the woven fabric, prior to the manufacturing processes in the weaving mill, often leads to a similar predictable appearance in the final outcome with the corresponding weave design. The increase of the employment of elastic textile yarns in knitting fabrics for comfort stretch or outdoor sports wear knit products has, however, resulted in difficulties in predicting the final appearance of the knit structure design. Due to the stretchability and exceptional recovery behavior of the elastic yarns such as polyurethane elastomeric yarns, the appearance of the final product often differs from the initial knit design. At textile CAD program for preparing tricot knit designs has been employed in this study to predict the two dimensional appearance of the design. The similarities between the designs and corresponding knit products seem to be acceptable for the two-dimensional textile CAD program in this study. However, when elastomeric yarns are partially employed in the polyester filament tricot product, a considerable amount of departure from the design is apparent due to the constriction and/or deformation of property differences in the elastomeric yarns and polyester filament yarns. Therefore, another purpose of this study is to measure the departure of the final tricot product from the initial tricot design, especially in the case employing elastomeric yarns in the knit structure together with regular polyester filament yarns. For measuring the three-dimensional departure, a 3D scanning system has been used for the mesh reconstruction of the fabric specimen. Hopefully, the result from this study will be used as a guide to modify and improve the current textile CAD program proposed for the two-dimensional simulation of the tricot.

• Proceedings of the Korean Fiber Society Conference
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• 2003.04a
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• pp.255-258
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• 2003

합섬소재를 이용한 의류용 직물설계1)에 있어 원료의 특성과 경ㆍ위사의 번수, 직물의 조직 및 밀도에 따른 직물설계 조건$^{2)}$ 은 다양하게 변할 수 있다. 그럼에도 불구하고 현장에서 적용할 수 있는 이론적 배경과 실제 현장에서 적용할 수 있는 데이터는 미흡한 수준이다. 따라서 다품종 소량 생산 체제에 대비하는 다양한 소재의 설계에 필요한 Data Base 구축이 필요한 실정$^{3)}$ 이다. 본 연구는 직물용 CAD System에서의 합섬 의류용 직물설계에 응용 가능한 DB를 구축하기 위해 국내 직물설계$^{4)}$ 와 일본 직물설계$^{5}$)를 비교하여 국내직물의 수준을 향상시킬 목적으로 실제 현장에서 사용되고 있는 각각 100여 종류의 직물설계조건들을 조사ㆍ분석하여 국내와 일본 직물설계를 비교함으로써 감성 의류용 합섬 소재 설계에 있어 체계적인 지표가 되고 보다 우수한 품질을 위한 직물설계의 기초자료를 제공함으로써 현업에 있는 업체와 기관에 도움을 주고자 한다. (중략)

• Transactions of the Korean Society of Mechanical Engineers A
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• v.30 no.4 s.247
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• pp.473-480
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• 2006

This paper explains analytical and experimental studies to evaluate the natural frequency of a composite carbody of Korean tilting train. The composite carbody with length of 23m was manufactured as a sandwich structure composed of 40mm-thick aluminium honeycomb core and 5mm-thick woven fabric carbon/epoxy face. From the finite element analysis, the 1st bending and 1st twisting natural frequency of the composite carbody were 11.67Hz and 14.4Hz, respectively. In order to verify the analytical results, the natural frequency measuring tests were performed. The measured 1st bending and twisting natural frequencies of the composite carbody were 10.25Hz and 11.0Hz, respectively. Both of these results satisfied the design requirement.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2000.04a
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• pp.120-125
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• 2000

A heddle frame is the major part of a loom that produces woven cloth by insertion of weft yarns between warp yams. Warp yarns are manipulated by many heddles fixed in a heddle frame. Recently, the up and down speed of heddle frames has been increased much for the increase of productivity, which induces higher inertial stresses and vibrations in the heddle frame. The heddle frame has the rectangular cross-section. For the design of box type beams of rectangular cross-section, extensional stiffness EA, flexural stiffness El, and torsional stiffness GJ as well as the vibration characteristics are important and should be simultaneously considered. Tn this paper, the vibration characteristics of the composite and the composite sandwich beams for high-speed heddle frame were tested by impulse frequency response.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.384-387
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• 2002

In the resin transfer molding, there are many advantages such as high volume, high performance, and low cost, The permeability is essential in the design and operation of the process, Traditionally, the determination of permeability can be divided as three methods, which are experimental measurement, analytical, and numerical prediction using the Darcy's law. In this study, the permeability in the microscopic level is first computed on the square-packing and hexagonal packing structures of the filaments inside the yarn by using CVFEM. (omitted)

• Proceedings of the Korean Geotechical Society Conference
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• 1993.10a
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• pp.33-42
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• 1993

Geocell is a three dimensional cellular confinement system that forms a reocomposite mattress with infill material to increase the bearing capacity dramatically rather than geotextiles of nonwoven and woven fabric type and geogrid. In terms of design, this geocell confinement is quite complex to assess and is different in its hieoretical evaluation and its concept from other geosynthetic products. Thsi study is aimed to help a basic understanding on Geoweb system, which is known to be the most effective and easiest in handling among the geocell systems ever developed, by introducing two method of interpretation for the improvement of bearing capacity. Thus the writers are sillingly to help the geotechnical engineers and the site engineers who might be encountered with the bearing capacity problems on site.

• Transactions of the Korean Society of Mechanical Engineers
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• v.16 no.1
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• pp.162-174
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• 1992

Blades are one of the critical parts of the wind machine. This paper presents a design procedure for the blade of a 7m diameter horizontal axis wind turbine with the constraint conditions of stresses and fundamental frequency. This blade consists of glass/polyester woven fabric and unidirectional prepreg. It was firstly designed by the classical beam theory on the assumption that torque box sustains all external loads and the reliability of the blade was then inspected in the preliminary estimation by using FEM.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2003.11a
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• pp.1351-1355
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• 2003

최근 의류용 감성소재가 다양해지면서 소재의 특성에 따른 최적 설계가 data-base에서 빨리 공급 될 수 있다면 시행착오에 따른 시간과 경비가 적게 소비되면서 소비자의 요구에 빨리 대응할 수 있는 소위 Q.R.도 가능하게 될 것이다. 이러한 감성 의류용 직물의 data base화를 위해서는 rapier, water-jet, air-jet 등 직기에 따른 소재의 설계분포 그리고 직기의 종류에 따라서 직물 설계 data의 분포가 어떠한지를 우선 조사하여야 한다. 본 연구에서는 국내 3개 업체의 실제 현장에서 생산되고 있는 PET 소재의 감성의류용 직물소재의 설계 Data를 직기별로 구분하고 직물 설계 조건들을 조사ㆍ분석하여 경사, 위사 번수별 조직계수를 계산하여 이들 data를 data-base화하고 도시하였다. 또한 이들 분석된 그래프에서 직기 종류별, 직물 조직별, 소재 item별 조직계수와 직물밀도를 예측할 수 있는 방법을 제시함과 더불어 조직에 따른 이들 직물의 설계조건을 제안함으로서 실제 현장에서 쉽게 사용할 수 있는 연구자료를 업체에 제공하고자 한다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.33 no.4
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• pp.353-359
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• 2009

Wire-woven Bulk Kagome (WBK) is a new truss type cellular metal fabricated by systematic assembling of helical wires in six directions. In this work, the experiments of mechanical behaviors of WBK cored sandwich panels subjected to bending load were performed and the results were compared with those by the corresponding analytic solutions. And also, finite element simulations were performed to validate the optimal design according to the analytic solutions. It is found the sandwich panel with WBK core performed excellently in terms of energy absorption and deformation stability after the peak point as well as the load capacity.