• Journal of Sericultural and Entomological Science
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• v.28 no.2
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• pp.65-73
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• 1986

These studies are carried out to improve silk availability for anticrease by useing methacrylate monomer polymerization method with in silk fiber. For this purpose, degree of anticrease, stiffness and shrinkage of various silk fabrics, included finish or not, after repeat of washings and polyster fabric was compared as standard. The adopted samples are ; 1. Polyester, Georgette, Woven density…90cm-85g/m 2. Silk, Twill, Degumed, Light, Woven density…90cm-90g/m 3. Silk, Twill, Degumed, Heavy, Woven density…90cm-200g/m 4. Silk, Stain, Degumed, Light, Woven density…90cm-90g/m The reached results are as followings. 1. The results of improving on anticrease by the finished method were about ten per cent increase against their original samples. 2. The light density silks showed satisfactory improve for anticrease, but the heavy one remained as rather poor condition. 3. The results for degree of textile stiffness were investigated to make sure reserve their textile feeling and observed to be good condition upon the finish work. 4. Textile shrinkage after the repeat of soap wash was investigated on indivisual test sample and silk fabrics showed more shrinkage than polyester which it seemed to be tentering shrinkage druning their general finishing processes. 5. The investigation showed that anticrease, stiffness and shrinkage of the sample textile were more or less deteriorated regardless silk or polyester by the repeat of washings. These matters are considered that such results were obtained because of the fiber fatigue nature. 6. The report reached that silk textiles should be used by dry cleaning methed after finish of any resin finish to reserve their improved anticrease nature.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.3
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• pp.495-505
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• 2016

This study explores and selects an appropriate material that considers light and soft physical properties as well as activity for impact absorption pads that can be used to develop practical impact protective clothes worn during daily life by the elderly to reduce the impact of falls. Physical properties, impact absorption performance, and compression characteristics were evaluated on 5 types of foam, 2 types of 3D spacer fabric, and 3 types of polymer gel to select a material appropriate for the pad to be inserted into impact protective clothes. The evaluation of the physical properties showed that 3D spacer fabrics had lower density compared to other materials and polymer gels had the highest density. The elongation percentage was higher in foams than 3D spacer fabrics and EPDM foam had the highest elongation percentage. The impact absorption performance of honeycomb polymer gel was better than foams and 3D spacer fabrics. As a result of looking into compression energy and compression characteristics of materials, 'CR foam A' was found to absorb the largest amount of compression energy, 24.1%, among foams and polymer gels. A high energy absorption rate of 50.0% (or above) was indicated by 3D spacer fabrics; however, foams and polymer gels showed a progressive deformation of energy compression / recovery curve with 3D spacer fabrics that showed drastic deformation. Based on characteristics of materials, 'CR foam C' and EPDM with relatively high absorption performance can be used as protective pad materials among foams. Among polymer gels, 2 open-type polymer gels that have relatively low impact protective performance but a relatively lighter weight on human body (compared to closed-type) are considered appropriate protective pad materials.

• Journal of the Korean Ceramic Society
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• v.50 no.6
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• pp.364-371
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• 2013

The sintering behavior of monolithic SiC is examined using the binary sintering additive of $Al_2O_3$-rare earth oxide ($RE_2O_3$, where RE = Sc, Nd, Dy, Ho, or Yb). Through hot pressing at 20 MPa and $1750^{\circ}C$ for 1 h in an Ar atmosphere for 52 nm fine ${\beta}$-SiC powder added with 5 wt% sintering additive, a SiC density of > 97% is achieved, which indicates the effectiveness of $Al_2O_3-RE_2O_3$ system as a sintering of additive for SiC. Based on this result, 7 wt% of $Al_2O_3-Sc_2O_3$ is tested as an additive system for the fabrication of a continuous SiC fiber-reinforced SiC-matrix composite ($SiC_f$/SiC). Electrophoretic deposition combined with the application of ultrasonic pulses is used to efficiently infiltrate the matrix phase into the voids of $Tyranno^{TM}$-SA3 fabric. After hot pressing, a composite density of > 97% is obtained, along with a maximum flexural strength of 443 MPa.

• Journal of the Korean Society of Costume
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• v.57 no.8
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• pp.37-47
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• 2007

This study is considered about the fabrics of the tomb of King Muryeong at the Baekje(百濟) Period. First, there were silk fabrics such as compound woven silk(錦), twill damask(綾), complex gause(羅) and plain weaved silk(平絹). All of compound woven silk(錦) are the warp-faced compound tabby(經錦) of plain weave and the density is various from high to low one. The twill damask(綾) was a variation of twill damask weaved with a six strand warp thread. The complex gause(羅) made patterns as a set of 2 strand, 4 strand, 6 strand and 8 strand warp threads are weaved alternately with the weft. There were three kinds of plain weaved silk(平絹). The first was weaved densely without space between strands. The second was weaved with a small space between strands. And the third was weaved with a two strand warp thread, having a space between the threads. On the other hand, several pieces of well preserved ramie cloth were excavated. Of the, the densest one has the density of 125 strand/inch for the warp and the weft. In addition, strings made of flax thread were found. This suggests that flax fabrics may be found additionally if the hardened lumps of fabrics are resolved and analyzed. Other materials discovered include knits, knotted strings, embroideries, threads and floss. Pieces considered knits and knotted strings occupy a large part of fabrics excavated from King Muryeong's Tomb, and in particular knotted strings show various knotting methods. In addition, embroideries such as chain stitch and button hole stitch are clearly observed. What is more, there are silk threads and hemp threads, which are presumed to have been used for dangling ornaments such as Yeongrak(瓔珞) and beads or for sewing. Besides, floss was found between fabrics.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2007.11a
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• pp.398-398
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• 2007

The Liquid Crystal (LC) alignment uniformity is very important in LC devices. The alignment mechanism of LC molecules on a rubbed polyimide (PI) surface is very important for both LC fundamental research and application. So, Generally a rubbing method to align LC has been widely used to mass-produce LCD panels. But because rubbing method is contact method between rubbing fabric and indium-tin-oxide glass or flexible substrate, rubbing method has some defects, such as the electrode charges and the creation of contaminating particles. Thus we strongly recommend a non-contact alignment technique for getting rid of some defects of rubbing method. Most recently, the LC aligning capabilities achieved by ion-beam exposure on the organic and nonorganic thin film surface have been reported successfully. In this research, we studied the tilt angle generation and electro-optical performances for a NLC on homeotropic polyimide surfaces with ion-beam exposure. The LC aligning capabilities of a nematic liquid crystal (NLC) on a homeotropic PI surface using a new ion-beam method were studied. On the homeotropic PI surface, the tilt angle of the NLC by exposure ion-beam had a tendency to decrease as increased ion-beam energy density. And, on the homeotropic PI surface, the alignment character of the NLC with respect to ion-beam energy was good. And we achieved satisfactory result for EO character.

• Textile Coloration and Finishing
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• v.34 no.1
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• pp.38-45
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• 2022

Sound absorbing materials are being developed in various materials and shapes and they are being applied in many fields such as construction, transportation, civil engineering, and sound. Among many sound-absorbing materials, polyester fiber has no environmental problems and harmfulness, and is a material with good sound absorption properties while being inexpensive. So it is manufactured as a nonwoven sound-absorbing material and used in various fields. In this study, polyester dry-laid nonwoven with different basis weight were manufactured using three types of polyester staple fibers: regular solid, single-hole hollow, and low linear density. We focused on the effects of the properties of the fibers, which constitute nonwovens, on the sound absorption properties, and we considered the basis weight. As the basis weight of the nonwoven fabric increased, the pore size became smaller and the air permeability was lowered, but the sound absorption coefficient was higher. However, the single-hole hollow polyester fiber did not contribute to the increase of the sound absorption coefficient of the nonwoven. It was established that, lower fiber fineness caused the sound absorption coefficient of the nonwoven to be increased. It was also found that the increase in the sound absorption coefficient due to the application of low fineness appeared from a certain basis weight or more.

• Textile Coloration and Finishing
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• v.34 no.4
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• pp.224-233
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• 2022

Recently, consumer tastes of various classes at home and abroad prefer comfortable, unadorned, and simple clothing, and the athleisure trend, which can be used freely in daily life as well as exercise, has expanded to overall clothing products. Existing materials used for athleisure are composite knitted fabrics using polyester yarn and PU yarn, which has problems due to a chronic lack of color fastness and contamination by dyes even when PU laminating is applied, making it difficult to apply various colors. There is a quality problem in which deformation of the product occurs due to lack of durability. In this study, CDP yarn(75de/72f) and PU yarn(40de) were selected to commercialize the circular knitting for athleisure using CDP yarn in order to solve the problems that occur in the dyeing and laminating process when using polyester materials. CDP yarns were used to knit into single(CP75-S) and double(CP75-D) knit and single knit were found to be suitable as athleisure fabrics. After pretreatment and treatment under various conditions, the stainability of CDP circular knitting was examined. After pretreatment and dyeing process under various conditions, the property of scouring and dyeability of CP75-S were evaluated.

• The Research Journal of the Costume Culture
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• v.30 no.4
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• pp.579-593
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• 2022

This study examines the surface characteristics, electrical conductivity, electromagnetic wave blocking characteristics, infrared (IR) transmittance, stealth function, thermal characteristics, and moisture characteristics of IR thermal imaging cameras. Nylon film (NFi), nylon fabric (NFa), and 5 types of nylon mesh were selected as the base materials for aluminum sputtering, and aluminum sputtering was performed to study IR thermal imaging, color difference, temperature change, and so on, and the relationship with infrared transmittance was assessed. The electrical conductivity was measured and the aluminum-sputtered nylon film demonstrated 25.6kΩ of surface resistance and high electrical conductivity. In addition, the electromagnetic wave shielding characteristics of the sputtering-treated nylon film samples were noticeably increased as a result of aluminum sputtering treatment as measured by the electromagnetic wave blocking characteristics. When NFi and NFa samples with single-sided sputtering were placed on the human body (sputtering layer faced the outside air) and imaged using IR thermographic cameras, the sputtering layer displayed a color similar to the surroundings, showing a stealth effect. Moreover, the tighter the sample density, the better the stealth function. According to the L, a, b measurements, when the sputtering layer of NFi and NFa samples faced the outside air, the value of a was generally high, thereby demonstrating a concealing effect, and the △E value was also high at 124.2 and 93.9, revealing a significant difference between the treated and untreated samples. This research may be applicable to various fields, such as the military wear, conductive sensors, electromagnetic wave shielding film, and others.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.10
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• pp.96-106
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• 2014

Previous academic research on FPGA tools has relied on simple imaginary models for the targeting architecture. As the first step to overcome such restriction, the issues on analytic placement and legalization which are applied to commercial FPGAs have been brought up, and several techniques to remedy them are presented, and evaluated. First of all, the center of gravity of the placed cells may be far displaced from the center of the chip during analytic placement. A function is proposed to be added to the objective function for minimizing this displacement. And then, the density map is expanded into multiple layers to accurately calculate the density distribution for each of the cell types. Early fixation is also proposed for the memory blocks which can be placed at limited sites in small numbers. Since two flip-flops share control pins in a slice, a compatibility constraint is introduced during legalization. Pre-packing compatible flip-flops is proposed as a proactive step. The proposed techniques are implemented on the K-FPGA fabric evaluation framework in which commercial architectures can be precisely modeled, and modified for enhancement, and validated on twelve industrial strength examples. The placement results show that the proposed techniques have reduced the wire length by 22%, and the slice usage by 5% on average. This research is expected to be a development basis of the optimization CAD tools for new as well as the state-of-the-art FPGA architectures.

• Journal of the Korean Society of Clothing and Textiles
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• v.26 no.10
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• pp.1390-1400
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• 2002

The purpose of this study is to categorize the type of fabrics and to analyze weaving method on the silk fabrics from ewongun's Tomb. The conclusions of this research are as follow. 1) Among the 26pieces of excavated clothes,98% of them were made of silk fabric and among them 84% used high-quality non-patterned silk I would assume, therefore, that the tomb was owned by a person who had a dignified yet humble tagte of higher society. 2) The weaving methods of textiles are plain weave, twil1 weave, satin weave. Plain weave includes spun silk tabby, fine filament silk tabby, raw silk tabby, thine silk tabby, damask on tabby, twill weave includes twill damask with different directions, satin weave includes non-patterned satin damask,5-end satin damask(4/1 warp faces ground, l/4 wok faced pattern). As the result of literature survey, I settled the names of textiles as follows; tabby was called Myunju, Saeju, Saengcho, and Sookcho according to the kind and density of silk threads used; Damask on tabby was ca]led Hwamunju) Twill damask was called Hwmunnung Satin damask was ca]led Hwamundan if they bear patterns by themselves or Mumundan if they don't have any patterns on them.