• Transactions of the Korean Society of Mechanical Engineers A
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• v.28 no.4
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• pp.443-452
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• 2004

In recent year, composite materials are increasingly used in various fields of engineering because of its superior properties. The relationships of between crack propagation and AE characteristics fer CFRP plain woven laminate composites are examined. AE signals are measured during the fracture behavior tests. The purpose of study is to estimate the crack extension behavior with AE characteristics according to the load orientation fur plain woven CFRP laminate composite.

• Journal of The Geomorphological Association of Korea
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• v.28 no.3
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• pp.1-11
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• 2021

The drainage area of the Miho stream is composed of granitic basins, gneissic and sedimentary mountains. 80 percent of the Miho stream flows through the Jincheon basin and the Cheongju inner-plain within the Daebo granite belt. Because the deep weathering of granitic hills provides a large amount of sands to the streams, there are wide floodplains with thick alluvium developed in the basin and plain. The thickness of the alluvium is 5~10m and the width of the floodplains is 2~2.5km. In the basin outlet area where a stream passes through the mountain canyon, wide floodplains and deep alluvium are developed in other riverside. The Miho stream is a sand-gravel channel flowing through the Cheongju inner-plain with wide floodplains and deep alluvium formed by deep weathering of granite.

• Journal of the Korean Home Economics Association
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• v.2 no.1
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• pp.220-231
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• 1960

• Journal of the Korean Magnetics Society
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• v.12 no.1
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• pp.7-13
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• 2002

The studies of non-figure plain coarse pottery from Jeju island is very important because it can explain the characters of plain coarse potteries of the bronze age and the early iron age. In this study, We analyzed the non-figure plain coarse popery from Jeju island in two ways. One is analysis of the chemical composition using X-ray fluorescence spectrometer and X-ray diffraction, the other is analysts of clay mineral contained iron, oxidized iron's genus, valence state and magnetic properties using Mossbauer spectroscopy. We confidence that non-figure plain coarse pottery is chiefly made of silicate minerals, like SiO$_2$. The content of noncrystalline ferrihydrite is supposed to be below 5-10 wt%, non-figure plain coarse pottery is considered to partly consist of Jeju island clay, which is made of neutral volcanic rock and the valence state of iron is Fe$\^$2+/ and Fe$\^$3+/. We presume the reason that the magnetic hyperfine field is lower than that of pure goethite is the change of crystal structure which transforms the combination states of Fe ions while the clay is being fired.

• Journal of the Korean Society of Costume
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• v.57 no.5 s.114
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• pp.1-11
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• 2007

The purpose of this study was to analyze and minimize structural error between sample knitting and actual knitting in weft knitting apparel. Basic stitches used in this study were plain stitch, $0{\times}0$ rib stitch, $1{\times}1$ rib stitch, $2{\times}2$ rib stitch, Milan rib stitch. They were knitted into two different gauges(7 and 12 gauge) and 6 different sample sizes by computer program. The weight, length and width of these 5 basic knitting stitches were measured and their changes according to gauge, stitch and knitting were calculated and analyzed. The results were as follows; The weight of $0{\times}0$ rib stitch was the largest, followed by Milan rib stitch, $2{\times}2$ rib stitch, plain stitch and $1{\times}1$ rib stitch. As the density of stitch per unit area increases, the weight increases. The length of $0{\times}0$ rib stitch was the largest, followed by plain stitch, $2{\times}2$ rib stitch, $1{\times}1$ rib stitch and Milan stitch in both 7 and 12 gauge. As the number of course increases, the length increases accordingly. However, its increase ratio shows higher than that of number of course. It means that the reduction in number of course is needed to get aimed length. The width of Milan rib stitch was the largest, followed by $0{\times}0$ rib stitch, plain stitch, $2{\times}2$ rib stitch, $1{\times}1$ rib stitch in 7 gauge. In 12 gauge, Milan stitch, plain stitch and $0{\times}0$ rib stitch were the highest, followed by $2{\times}2$ rib stitch and $1{\times}1$ rib stitch. It showed that the change in shape of stitch influenced on the width more than the length of stitch.

• Korean Journal of Soil Science and Fertilizer
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• v.49 no.4
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• pp.310-317
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• 2016

This study aimed to evaluate the nutrient load balance from rice paddy fields with different topographies, alluvial plain and local valley. Continuous monitoring from May to September, 2013 was conducted for water quantification and qualification from alluvial plain in Yeoju region (32 ha) and local valley in Jincheon region (24 ha). The discharge rates of T-N from the alluvial plain were 57.2, 5.84, 22.7, and $5.20kg\;ha^{-1}$ for irrigation, precipitation, drainage, and percolation, respectively. In case of local valley, T-N loads were 34.6, 4.73, 21.1, and $4.15kg\;ha^{-1}$ for irrigation, precipitation, drainage, and percolation, respectively. In contrary, the T-P loads from the alluvial plain were 2.23, 2.22, 2.54, and $0.41kg\;ha^{-1}$ for irrigation, precipitation, drainage, and percolation, respectively. In case of local valley, T-P loads were 1.44, 1.57, 1.82, and $0.34kg\;ha^{-1}$ for irrigation, precipitation, drainage, and percolation, respectively. The nutrient contents in drainage water were influenced by the amount of waters, rainfall, and surface drainage water. The Pearson correlation analysis showed that rainfall was significantly correlated with nutrient loads from July to August due to the amount of runoff in local valley paddy field, and irrigation was related with nutrient loads of drainage from July to August. This study showed that paddy rice farming in alluvial plain and local valley might be beneficial to water quality protection.

• Journal of the Korea Concrete Institute
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• v.28 no.3
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• pp.357-363
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• 2016

To solve the exhaustion problem of natural aggregate which were create the high value in construction and environmental industry, recycled aggregates have considerable benefits than other materials. However, even though many researches have been conducted with recycled aggregates, building structures with recycled aggregated are rarely constructed because it has lower quality than natural aggregates have. In this study, mechanical and strain properties of recycled aggregates concrete containing steel fibers have been reviewed in order to complement performance of recycled aggregates concrete. As results, recycled aggregates concrete showed lower compressive strength and elastic modulus than plain concrete. But, recycled aggregates concrete containing steel fibers showed equivalent performance with plain concrete. In review of drying shrinkage and creep coefficient, recycled aggregates concrete containing steel fibers showed similar behavior with plain concrete in the range of 0.5 Vol.% fiber content rate by internal restraint effect, moisture transport restraint effect and strength enhancement effect of steel fiber. Therefore, it is considered that mixing steel fibers with concrete is the effective method as a active application plan for recycled aggregates.

• Journal of the Korean Society of Costume
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• v.53 no.4
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• pp.113-129
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• 2003

This study examined textiles used for the ancient costumes that are excavated from tombs of the Chosun dynasty, focusing especially on Po(overcoat). The result of the study is that silk occupies 79.8% of all the textiles used for Po, and cotton and linen follow. The weaving method of silk was primarily plain and satin weaves. However the use of twill, gauze, and double weave, that had led weaving methods of silk during the Koryo dynasty, are considerably decreased in Chosun dynasty. Danlyeong(단령) and Cheollik(첩리) had been made of various textile fabrics like cotton, linen, silk and blended fabric before Imjinwaeran(임진왜란). After the war, they were simplified in gauze weaved silk or satin weaved silk, And also patterned fabric were widely used for them than other Po. Simple fabrics like cotton, linen and plain weaved silk had been used for Aekjureum(액주름) and Jiklyeong(직령) before Imjinwaeran. After the war, Jiklyeong was used as underwears of Danlyeong, so it was made of high quality patterned silk. Dopo(도포) and Changuiryu(창의류) were mainly excavated from tombs after the war, high quality plain weaved silk are used than gorgeous Patterned silk. For the Dopho(답호) and Bansuui(반수의), before the war, they were made with various textiles such as plain weaved silk, twill weaved silk, satin weaved silk, cotton, linen, and blended fabric. But after the war plain weave was mainly used. In Jangui(장의), since it was mostly for women, many kinds of women's patterned silk were used in than any other Po. There were only a few excavation of Simui(심의) and most of them were made of ramie and were hemmed in black satin without pattern.

• Textile Coloration and Finishing
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• v.11 no.2
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• pp.9-18
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• 1999

In order to establish fundamental data for the betterment of Polyester microfiber fabric handle, a study by using fixed warp of ITY yarn samples with P/F, DTY, and ITY weft yarns was performed. For this purpose the samples of total 27 kinds were prepared. That is, each sample yarn was twisted in three ways and for each twisted yarn the fabric structures were modified in three ways, plain, twill, and satin. The examination was done by focusing on the point of the change of handles and the characteristics of the mechanical properties of the samples with the change of yarn and the fabric structure. The handles and the mechanical properties were examined with the KES-F system suggested by Kawabata. The results were as follows : 1. WT and MIU increased with increasing the twist. By comparing WT and MIU by yarn, DTY was higher than P/F. It appeared that twill and satin were higher than plain. 2. The bending rigidity change in DTY with increasing the twist was not significant, however in P/F it appeared apparently decreased with increasing the tlvist. Also, it appeared that when using P/F as weft the bending rigidity was higher than when using DTY and the twill structure appeared higher than the satin structure. 3. In shear force the increasing rates of plain and the twill were higher than satin. When DTY and P/F were used as weft, the shear force was higher in ITY and DTY than in P/F case. 4. Koshi appeared higher in the order of plain, twill and satin. When DTY and P/F were used as the weft Koshi increased with increasing the twist in plain, however in twill and satin it appeared to decrease. In hand value ITY(=7.5) appea.ed to be highe. than DTY and P/F(=6.5). 5. In all cases Shinayakasa decreased with increasing the twist. The hand values observed that satin was =4, twill was =3, and plain was =1.5. 6. Fukurami showed no significant change with increasing the twist in DTY, however in P/F and ITY it decreased.

• Journal of the Korea Institute of Building Construction
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• v.9 no.6
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• pp.71-78
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• 2009

The analysis of the effect of loading on chloride penetration into concrete is very important. In this study, we confirmed that the chloride penetration rates for plain and BFS concrete were increased by 47% and 89% under compressive stress, respectively. The diffusion coefficient of BFS concrete was lower than for conventional concrete with no BFS, no loads, and under stressed states. Therefore, BFS substitution plays an important role in the repression of chloride penetration even under compressive stress. Under compressive stress,the diffusion coefficient for BFS concrete was higher with increasing stress, and this was also the case for plain concrete. However, BFS concrete was strongly influenced by compressive stress in comparison to plain concrete. We investigated the effect of the difference of specific surfaces on the diffusion coefficient. As a result, the larger specific surface of BFS exhibited a lower diffusion coefficient. This tendency was most pronounced under the high stress conditions.