• Applied Chemistry for Engineering
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• v.17 no.3
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• pp.331-334
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• 2006

In this study, the ultra-fine fibers (UFs) having an alignment were prepared by electrospinning process, using different collectors made from various materials and collecting methods. A spinning solution was prepared by dissolving poly(amide-co-imide) (PAI) in NMP. The UFs were prepared by using various collectors and collecting methods, and the fibrous shapes were observed by SEM. As a result, a sort of materials of collectors and the collecting methods had not influenced on the average diameters of fibers but the forms of them. The just accumulated UFs on the collectors formed net structures, which had no alignment. On the contrary, the continuously collected UFs formed long fibers with alignment. It was found that the water collector played the roles of the fiber haul, temporary collector, moving path of fibers, and caused some friction between fibers and water, attributed to the formation of continuous UFs at a suitable collecting speed.

• Journal of the Korean Geosynthetics Society
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• v.4 no.1
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• pp.7-15
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• 2005

In recent years, the geotextile tubes filled with dredged material have been used in dike and breakwater construction for a number of projects around the world, and their use in this field is growing very fast. One of the most attractive advantages of geotextile tube technology is can be use the in-situ filling materials by hydraulic pumping, it can be also established lower costs and fast construction than other technology. Geotextiles form one of the two largest groups of geosynthetics and it is commonly made by two major types of polymer material(Polypropylene, Polyester). The objective of this paper is to examine several issues associated with drainage function and feasibility of geotextile tube structure such as filtering efficiency, dewatering efficiency, and filling process with polymer materials. Based on the laboratory filtering test and in-situ tests, polypropylene goetextile is more effective for drainage function of geotextile tube technology.

• Proceedings of the Korean Fiber Society Conference
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• 1994.04a
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• pp.59-59
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• 1994

• 보존과학연구
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• s.32
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• pp.25-35
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• 2011

Wood vinegar and Asarum sieboldii Miquel were selected as candidate materials showed antimicrobial activity and insect repellent activity. These natural pesticides have its own color and these could cause color difference on fabric materials. In the present study, we investigated the color difference of undyed and dyed fabrics to evaluate negative effect of wood vinegar and A. sieboldii Miquel. Undyed and dyed fabrics were exposed to natural pesticides of various concentrations for six months in relative humidity 70% and temperature $28^{\circ}C$. After exposure of pesticides, color difference (${\Delta}E*$) were investigated at two weeks intervals for six months. As a results, dyed cotton, silk and undyed silk fabrics exposed wood vinegar were not nearly changed in their colors, but color of only undyed cotton fabric was clearly changed by wood vinegar. Especially color difference by wood vinegar on undyed cotton fabric was most distinct as the concentration increased. On the other hand, all of fabrics exposed A. sieboldii Miquel were not nearly changed in their colors for six months. Therefore, this study first suggests that wood vinegar and A. sieboldii Miquel as natural insecticides could be used to conserve for textile cultural properties from insects and microorganism, but wood vinegar couldn't use the high concentration on undyed cotton fabric.

• Proceedings of the Korean Fiber Society Conference
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• 1998.04a
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• pp.280-284
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• 1998

신체 보호와 체온유지를 담당하는 피부는 인체 최대의 감각기관이다. 피부에는 온각, 냉각, 압력, 통증, 촉각, 진동 둥을 느끼는 외수용감각기들이 산재되어 있다. 그 중에서 촉감은 건축 자재, 필기구 재질, 자동차 내장재, 의류 원단과 안감 등 신체와 접촉하는 소재에 있어 제품의 질을 결정짓는 중요한 요소이다. 특히 섬유에서의 질감이란 경제적인 면과 직결되는 문제를 안고 있다.(중략)

• Transactions of the Korean Society of Mechanical Engineers B
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• v.40 no.1
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• pp.55-63
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• 2016

New materials and shapes for a humidifying element were developed which outperformed the widely used crisscross glass wool Glasdek media design. The new material consists of 50% cellulose and 50% PET. The parallel channel configuration was devised to reduce excessive pressure loss caused by the reduced height (from 7.0 mm to 5.0 mm) of the crisscross configuration. For the same crisscross configuration, the humidification efficiency of the cellulose/PET element was 26% higher than that of the glass wool element. For the same cellulose/PET material, humidification efficiency of the parallel channel configuration was 14% higher than that of the crisscross configuration. As for the pressure drops, the cellulose/PET element was 2-52% higher than those of the glass wool element. For the same cellulose/PET material, the pressure drop of the parallel channel configuration was 14% higher than that of the crisscross configuration. Data were compared against the predictions from existing correlations and those by the proposed model.

• Journal of Radiation Protection and Research
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• v.30 no.1
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• pp.1-7
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• 2005

Radiation absorption parameters of carbon fiber panel were measured in comparison to acrylic panel. $30{\times}30cm$ sized 2mm thick carbon fiber panel and identical sized 6mm thick acrylic panel were placed in tray holder position and 0cm, 5cm, 10cm from surface of phantom. Radiation field size was $10{\times}10cm$. 50MU of 4MV photon was irradiated to the phantom with dose rate of 300MU/min. Source-to-phantom distance was 120cm. Radiation dose was measured with 0.6cc Farmer-type ionization chamber with 1cm build-up. Measurement was repeated thrice and normalization was done to the dose of the open field. Radiation transmission rate of carbon fiber panel is approximately 1% lower than acrylic panel of equivalent thickness. However, considering the strength of the material, transmission rate is higher for carbon fiber panel. Although carbon fiber panel increases the radiation dose when attached to the surface for about 2%, it normalizes the radiation dose to 97-99% of irradiated dose which could have been lowered to as much as 5-7.5% with acrylic panel. As carbon fiber panel is stronger than acrylic panel, radiation fixation device could be made thinner and thus lighter and furthermore, with increased radiation transmission. This in turn makes carbon fiber more ideal material for radiation fixation device over conventionally used acrylic.

• Journal of Conservation Science
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• v.33 no.5
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• pp.363-370
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• 2017

The aim of this study was to obtain information about two early-20th Century clothes, for which the "National Memorial Museum of Forced Mobilization under Japanese Occupation" has sought to receive preservation treatment. Optical microscopes and a scanning electron microscope were used to investigate the weaving of the clothes, and Fourier transform infrared spectroscopy(FT-IR) was used to investigate the fibers. Cloth A is believed to be a Japanese half sleeved inner wear(Hanjuban) used by women. Cloth B is believed to be working clothing that was checked by an Osaka plant. This was verified by a book written by the Japanese army. Both of the clothes were made mostly from cotton, although the inner wear also used viscose rayon on the neck collar. The button on the working wear was made of urea formaldehyde resin, an early precursor to plastic.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.243-246
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• 2002

자동차 차체 제작을 위해서는 차체의 견고성과 승객의 안전성을 동시에 고려하여 너무 강하거나 너무 무르지 않은 재질의 선택과 차체 설계의 최적화가 요구된다. 본 논문에서는 차량 충돌 시 자동차의 안전도를 향상시키면서 차량의 손상을 최소화 함으로써 수리비를 절감하기 위한 목적으로 TPU(Thermoplastic Polyurethane Elastomer)에 공기를 채워서 만든 에어백 자동차 범퍼를 개발하였다. (중략)

• Proceedings of the Korean Society for Agricultural Machinery Conference
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• 2017.04a
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• pp.64-64
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• 2017

노지 고추 수확작업은 7~9월에 걸쳐 5~6회 수행되며 가장 더운 한 여름의 태양볕에 노출되어 장시간 수확작업을 하며 노지채소 및 고추 수확작업시 자외선 과다 노출되어 악성흑생종, 광선각화증, 편평세포 암 및 각종 피부암발생의 원인되기 때문에 적절한 해가림 장치의 설계가 필요하다. 해를 가려주는 장치에 사용되는 재질로는 우산 및 양산에 널리 사용되어지는 섬유로 폴리에스테르를 선정하였으며 두께로 우산의 재질로 많이 사용되는 75 denier을 채택하였다. 코팅의 종류로는 Foam, Milky, Silver, 폴리우레탄을 채택하여 섬유의 코팅 종류에 따른 차단 효과를 실험하였다. 실험 방법으로서는 KS K 0850 텍스타일의 자외선 차단율 및 차단지수 시험방법에 의거 하여 실험하였다. 자외선 UV-A(365n/m), UV-B(315n/m) 측정장치는 자외선 센서, UV램프, 인디케이터로 구성된 측정기를 이용하였으며 각 재료별 5회 반복 실시하여 평균치를 산출 하였다. UV-A(365n/m) 측정값으로는 FOAM, MILKY코팅이 된 섬유재질이 KS의 우산 및 양산품질표시기준에 부합하여 해가림 장치에 사용이 적절하였으며 UV-B(315n/m) 파장 차단율 측정값으로는 KS의 우산 및 양산품질표시기준에 모두 부합되었다. 또한 해가림 장치는 태양고도에 따라 각도를 조절 가능한 형태로 설계하였으며 직사광선이 가장 강한 시간대인 10시부터 12시를 기준하여 틸팅의 최대 각도는 20도로 개발하였다. 또한 바람에 의한 날림현상을 방지하고 통풍효과를 높이기 위해서 해가림 장치의 섬유를 2중 구조로 설계하여 바람의 순환이 되게하였다.