• Journal of the Korea Concrete Institute
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• v.15 no.3
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• pp.386-391
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• 2003

Ready mixed mortar has been originated from lime industry of Germany and is being used widely in the world at present. In recent years, the studies of mortar with new faculty have been progressed. In this study, we used elvan instead of using sand in order to make cement mortar and investigated characteristics of elvan and mortar that used elvan. The major compositions of elvan were $SiO_2$ and $Al_2O_3$. The crystal phases of elvan were composed of quartz and sillimanite. Elvan had a lot of pore and absorption ratio was 2.09%. The compressive strength of mortar that used elvan satisfied korean industrial standards under 1:3 (mixing ratio) and water retentivity increased according to increase of elvan contents. Far infrared radiation and deodorization ratio increased and thermal conductivity decreased according to increase of elvan contents.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.941-944
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• 2008

Various ductile fiber reinforced cement composite(DFRCC) including large quantities of PVA fiber or steel fiber have been developed recently and studies to find applications in diverse domains are currently conducted actively. Regard to economical efficiency, DFRCC becomes competitive when applied as special elements and repair material with small quantities rather than the casting of large volume for the main body of structures in field. The authors have developed FRP-DFRCC composite slab for bridges and a wet spraying repair technique using DFRCC. In case of the application on FRP-DFRCC composite slab, it was found that there was no problems the structure and durability of it after passed 3 months. And in case of the application on the application of the deteriorated sewage box that passed 20 years, it was found that there was no difference the repair performance between domestic PVA fiber and the Japan. Therefore, DFRCC using PVA fiber, the concrete structures can be increased to performance and secured the economical efficiency.

• The Journal of the Korea institute of electronic communication sciences
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• v.11 no.6
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• pp.605-610
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• 2016

The ELCB(: Earth Leakage Circuit Breaker) is the only way being used to prevent accidents from happening caused by electrical disaster. However, the existing ELCB has a limit to prevent damages to life and property due to a electric fire and a human body electric shock caused by the resistive leakage current, because of detecting the total leakage current in the block range of 15mA~30mA. It also has problems such as reduced productivity and reliability due to malfunctions by capacitive leakage currents. In this study, we have implemented the algorithm for the resistive leakage current detection technique and developed the resistive leakage current detection module based on a MSP430 processor, 16bit signal processor and this module can be operated in a desired block threshold within 0.03 seconds as specified in KS C 4613.

• Journal of the Korean Institute of Gas
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• v.16 no.3
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• pp.16-21
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• 2012

In this study, the strength safety for 110 liter hydrogen fuel storage tank with 70MPa filling pressure has been analyzed using a FEM technique. The strength safety of a composite fuel tank in which is fabricated by an aluminum liner of 6061-T6 and carbon fiber wound composite layers of T800-24K and T700-12K of Toray, and MR60H-24P of Mitsubishi Ray has been investigated based on the criterion of a strength safety of US DOT-CFFC and Korean Standard. The FEM computed results on the strength safety of 70MPa hydrogen gas tank showed that the hydrogen fuel storage tank in which is fabricated by T800-24K and T700-12K of Toray, and MR60H-24P of Mitsubishi Ray is safe because those two carbon fibers have very similar material properties. But, the composite storage tank with a filling pressure of 70MPa in which is fabricated by T700-12K of Toray may not guaranty the strength safety, and thus this study recommends a composite hydrogen fuel tank under 60MPa.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.3
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• pp.138-144
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• 2017

In order to reduce carbon dioxide emission in construction industry, less amount of cement use can be one of the alternatives to manufacture concrete. One of the non-sintered construction materials are limestone, which is the raw material to manufacture ordinary Portland cement(OPC). A large amount of limestone have already been used as binders such as blended cement in Europe and US. Even European countries were already established the standard of blended cement, where the limestone can be used up to 35 percent. In this study, experimental researches were conducted to investigate the effects of limestone replacement on the mechanical properties and durability of concrete with 15%, 25% and 35% of limestone substitution to use limestone in blended cement. 15 percent use of limestone in blended cement developed equivalent or even higher compressive strengths compared to Plain mixture. Porosity of limestone cement with 15 percent substitution was much lower than Plain mixture. Most durability tests such as concrete carbonation, freeze-thaw cycle and drying shrinkage strains were conducted to evaluate long-term performance, and the test results indicated that 15 percent of limestone use did not significantly influence on the concrete durability compared with plain concrete.

• Journal of the Korean Society of Clothing and Textiles
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• v.25 no.6
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• pp.1046-1056
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• 2001

For the purpose of standardizing sizing systems for infants and children's clothing, the researchers surveyed 20 different apparel manufacturers in Korea. The apparel production sizing systems used in the industry were analysed. The researchers also compared standard apparel sizing systems developed for infants and children's clothing in Korea. ISO, Japan, and U.S.A. The followings are the results of this study. 1. As survey findings of companies's views about sizing systems, boys or girls sizing system needed to be developed for 3 years old and over. The plus sizes are needed to be developed and children 9 years old and over need the plus size. 2. The body size specification in most sizing systems collected shows that chest circumference was increased 2cm for every infants sizes, and 3cm for boys and girls'sizes, from size 100 to size 130. However, the chest and waist circumference measurements were increased 4 to 8cm for large sizes, from size 130 to size 170. 3. There are similarity and dissimilarity among the standard sizing systems of ISO, Japan(JIS), U.S.A(ASTM), and Korea(KS). The ASTM developed infants'garment sizes for the babies who are 24months old and under. The most national standards, however, developed infant apparel sizing system for the babies under 105cm tall or 4 years old. 4. The range of body measurements covered by boys/girls sizing system were different by the nation. The U.S. system (ASTM) is for boys and girls who are taller than 120cm. The Japanese system(JIS) is for the children who are taller than 90cm.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.8
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• pp.1117-1129
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• 2013

The sizing system for Korean Standard of Disposable Protective Coveralls (DPC) uses the ISO sizing system without modification even though the user suitability for Koreans is unverified. This study provides useful information to improve the size standard of Korean DPC by analyzing measurement DPC data from Korean men and women. The distribution of Korean measurements shows that the size sections were unsuitable for Korean men and women for a protective clothing size standard. Body types were categorized into five types based on a cluster analysis of representative men's and women's measurement factors. Two clusters mostly consisted of men, two other clusters mostly consisted of women, and the other cluster relatively evenly consisted of men and women. Therefore, characteristic body measurements and measurement distribution differences were identifiable for men and women. In conclusion, an unmodified ISO protective clothing size standard is unsuitable for Korean men and women and may cause fit problems. This study shows that a Korean Standard of protective clothing is beneficial for protective clothing manufacturers and wearers if smaller size intervals are added for women and the difference in the distribution of men and women is reflected in the current sizing system. ISO is appropriate to use a Korean Standard in this global era, however, it should be reviewed to provide improved Korean data.

• Resources Recycling
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• v.4 no.4
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• pp.16-21
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• 1995

When waste t~re/~vastmz otor oil is pyrolyzed. most of them hecome gaseous produds. and thc remaining onc, whascwelght is ahout in% oi the waste Ore, is pyrolyced residue mnstly composcd oi ca~bnn black A rescsrcll was canicrl nut loutilize lhe pyralyred residue of waste tnelwuste lnotol 011 us retnin~cing agent of asphall concrete, bescd on iolelg~r lesearchrepurl. This shows thal the properlies ol asphall concrele ~nclud~cd~ugl ah~l~tyre, sistance to Tear. temperature-v~scusilysusceptil,ilily u e g reatly improved when lhe pellellrcd hrln aI carlmn hlack usmg petroleum o ~als a hinder Iar ihe pellels isused with asphalt. The surface of the pyralyred resirh~ei s covned by ocl film and thla lnakes good comllatibllity with asphallIn order lo ulilk pyrolyzed residue as a reinforcing agenl oi lhe itsphalt concrete, various tests such as Marshnll tcsi, wheeltracking, and revelhng test has been carried out a1 KLER, Ko~ea I-lighway Coo~poration, and TCMO. Tcst lcsults satirry KSslandard, show "npmvements an the dynam~cs tab~l~lzym, d incrcase reslslance to wear at cold telnpelatule Invrsligadon wascarlied oul to sludg the possibility of soil pallul~on when pyrolyzed residue is used as a tzmioicing agenl. E~pcrimentalresulls show the rcsidue contained in thc asphall docs not cause cnv~ranma~lparlo blems.e cnv~ranma~lparlo blems.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.5
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• pp.3542-3547
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• 2015

There is commonly used the full depth excavation method of sewer pipeline maintenance in Korea. This induces couple of technical and social problems like increase of construction cost and time for excavation and backfill, increase of public complains and delay of traffic, and so force. In order to overcome these problems, lots of laboratory tests were carried out for sewer pipeline of maintenance materials with trenchless methods. The testing materials are liquid and hardened polyurethane, and polyurethane CIPP. The lab tests were followed by Korean Standard. There are no side effects, like harmless to the human body and air pollution with stink. Judging from the limited test results, all the items tested were satisfied the KS criteria.

• Journal of Fashion Business
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• v.4 no.1
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• pp.45-58
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• 2000

The purpose of this study is to provide for the basic data useful to the development of a quality bassiere featuring a good wearing feeling, to investigate the characteristics of breast shapes by age and suggest a brassiere sizing system for woman. For this purpose, the subjects of anthropometry were 220 women aged between 20 and 59. The anthropometric measurements were analyzed by various statistical methods mean, standard deviation, F-test, Duncan-test, Factor analysis, frequency. The results of this study can be summarized as follows; 1. According to the increase of age, the items of height were decreased and items of width, depth, circumference and length were increased, being obeser and breast point were drooped. So volume and bottom area of breast of 40 50's women were larger than 20 30's women and breast point width of 40 50's women was being wider by increase of the interior of breast. 2. From analyzing the effect of brassiere wearing, it was found that brassiere reformed the breast shape with the breast volume transferred from exterior part to interior part and the bottom area of breast diminished, so brassiere can have the breast location of adult woman up and the breast point width being centered 3. It was found that there was no direct linear relationships between under bust girth and cup size from analysis of breast measurements. Therefore those 2 factors(under bust girth and cup size) was brought into basic item of brassiere sizing system. From the dual distribution table whose intervals had been decided by KS K-0070(1999), it was picked out 12 sizes which had more than 4% of appearance for suggesting brassiere size chart. The sizing system covers 76.36% of all subjects and supply reference measurements relevant to brassiere manufacturing.