• Proceedings of the Korean Institute of Building Construction Conference
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• 2007.11a
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• pp.71-74
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• 2007

With the changes of times the building materials tend to extend the demand for application under the special environment. Since high-ductile mortar is developed, the building materials show excellent performance like toughness, compression, tensile, and bending, etc. in the general concrete from the existing brittle point. And, recently they are widely used as repairing and reinforcing materials both at home and abroad because they are recognized as excellence like durability and fire-resistance. However, it is in a situation of creating problems in durability because it frequently happened deterioration of buildings that have already repaired and reinforced at a time when it requires reconstruction of recently deteriorated construction structure recently. Therefore, in this study improved with a more repair Material development and reinforcement of the second high-ductile mortar products for a variety of basic materials were presented want, research plans used include traditional repair materials and the newly developed PCM (polymer cement mortar) structural reinforcement type indicated that comparison. PCM analysis in order to present a rate depending on the types fiber 0, 1.2 and 2.0(%) at three levels and mixture water according to ratios of weight to Plain in the 2.0 and 1.85(kg) at two levels is set, the results were as follows. 1) This study has shown that PCM had excellent strain hardening behavior at the same time that the bending stress increased according to the fiber contents. 2) This study has shown that it had the durability performance due to the high substance transmission according to the fiber contents.

• Electronics and Telecommunications Trends
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• v.18 no.6 s.84
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• pp.34-40
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• 2003

1998년 시작된 초고속 인터넷 서비스는 약 4년 만에 세계 1위의 보급률을 보이고 있을 정도로 우리 나라의 정보통신 인프라는 급속도로 성장하여 왔다. 최근 유무선 통합 및 통신과 방송이 융합되는 광대역 통합망(BcN) 환경에서 초고속 인터넷 서비스와 디지털방송 서비스를 제공하기 위한 초고속 인프라의 가입자망 형태는 동선 기반의 ADSL(Asymmetric Digital Subscriber Line)/VDSL(Very high-data rate Digital Subscriber Line) 및 광/동축 혼합망인 HFC, 광섬유 기반의 FTTH(Fiber To The Home) 등이 있다. 그 중에서 HFC는 그 동안 주로 케이블 TV 프로그램의 전송망으로 활용되어 오다가 최근 통신. 방송 융합 환경에서 초고속 인터넷 가입자망으로 부각되고 있다. 본 고에서는 HFC 망의 특성과 HFC 망의 핵심장비인 CMTS와 케이블모뎀의 시장 현황 및 전망에 대해서 알아보고, 광대역 통합망의 가입자망으로서의 HFC의 역할에 대해 논의하고자 한다.

• Journal of the Korean Institute of Rural Architecture
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• v.20 no.1
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• pp.27-36
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• 2018

At present, the elderly population in Korea is 14% of the total population and then We has entered an the society of advanced age. Along with this, elderly people with dementia and palsy are also increasing. The demand for elderly nursing homes for elderly people with severe diseases such as dementia and stroke is also increasing, and the existing buildings are being secured by Conversion of existing buildings. However, it is difficult to evacuate and fire due to the out of date of buildings by Conversion of existing buildings. For example, there is a fire in the Indukukwon, Pohang City and Hyosung Geriatric Hospital, Jangseong in Korea, which have changed the use of existing buildings. Many elderly people died in a night fire. It was because of the sandwich panel walls and PVC flooring material produced toxic gas instantly. In this study, we investigated the nursing home that changing the use and established fire prevention of human injury and countermeasure of evacuation. First, the sandwich panels which leading to deaths due to the toxic gas were installed in most nursing home. We recommend the RC, the masonry wall, and the glass fiber panel instead of the sandwich panels, In addition, the PVC flooring is most used in nursing home, the flooring material is considered such as the building stones, the tile, and the yellow soil closing instead of the PVC flooring. Second, we investigated the installation status of fire fighting equipment. As a result, the automatic-emergency open&shut equipment, the smoke ventilator and the evacuation slide were rarely installed. In order to secure the golden time in case of fire and to prevent the asphyxia caused by the toxic gas, the law should be amended to install the equipment.

• Proceedings of the Korean Information Science Society Conference
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• 2004.04a
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• pp.865-867
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• 2004

VOD, HDTV, 라이브 스트리밍 등의 서비스가 늘어나면서 FTTH(Fiber To The Home)의 고비용과 설비문제를 해결하기 위한 대안으로 PON(Passive Optical Network)이 부상하고 있다. 가입자망의 구조가 다양하게 진화하고 광 이더넷 기술이 발전하면서 가입자에게 최적의 대역폭을 할당하기 위해 서비스별 대역폭 할당방식이 요구된다. 따라서, 본 논문에서는 사용자의 대역폭 요구에 따라 OLT(Optical Line Termination)가 각 ONU(Optical Network Unit)에게 서로 다른 방식으로 대역폭을 파장별로 적절하게 할당하는 파장 다중 분할 Ethernet PON모델에서 스트리밍 서비스를 위한 모델을 제시하고 구현한다. 또한, 이더넷 지연에 대한 분석을 통해 모델의 효율성을 제시한다.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.6
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• pp.1016-1019
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• 1995

This study was conducted to investigate the nutrient composition of hydroponic water dropwort and the effect of blanching condition on ascorbic acid content. Nutrient composition of hydroponic water dropwort of mid harvest on the 30th day was measured in three portions of leaves, petioles and stems, and was compared with that of late harvest on the 40th day. Hydroponic water dropwort was obtained from the Department of Horticultural Science, Seoul National University. The results were as follows. The nutrients content of leaves were significantly higher in ash and ascorbic acid and lower in moisture, crude fat and crude fiber than those of stems and petioles. There was no significant difference in total vitamin A and thiamin contents between three portions. Ascorbic acid content of leaves harvested on the 30th day was the highest, 57mg/100g, and decreased to 18mg/100g in the leaves harvested on the 40th day. Marked increase in crude fiber and vitamin A content of leaves was observed in late harvest may be due to the maturation. The results of nutrient composition analysis suggest that the leaves of hydroponic water dropwort is important in ascorbic acid and ash. It is recommended that shorter blanching time and addition of 0.5% NaCl to the blanching water are better for higher ascorbic acid retention of hydroponic water dropwort. In conclusion, as hydroponic water dropwort has high content in ash, calcium, vitamin and free sugar with alkalinity, leaves as well as stems and petioles can be recommonded as a vegetable of high nutritional quality.

• Journal of KIISE:Information Networking
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• v.36 no.4
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• pp.360-368
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• 2009

Recently, broadband access networks have been competitively deployed all over the world with the development of various multimedia services for such a network. ETRI(Electronics and Telecommunications Research Institute) built the FTTH(Fiber-To-the-Home) service center to develop a next-generation equipment and a high-quality service/platform as well as to promote domestic industry in the field of optical communication. The FTTH service center has a variety of test equipments such as FTTH standard testbed for a BMT(bench mark test), a network operation center, and IPTV service equipments. Also, ETRI deployed a new type of commercial optical access networks cooperating with ISP(Internet Service Provider). This paper presents the performance evaluation of FTTH E-PON(Ethernet Passive Optical Network) system as a platform for TPS(Triple Play Service) based on QoS(Quality of Service) and QoE(Quality of Expericence) issues. This FTTH E-PON system is successfully demonstrated as an optical access network system by commercial network service provider and the FTTH service center of ETRI.

• Journal of the Korean Society of Clothing and Textiles
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• v.35 no.8
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• pp.982-990
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• 2011

Kenaf fiber can be obtained by decortications of the kenaf plant stem. The properties of the kenaf fiber treated by alkali (NaOH) were investigated by spectrocolorimeter, SEM, X-ray diffractometer, FT-IR and TGA. The kenaf fibers treated by alkali became darker and their Munsell color values changed from Y (yellow) to YR (yellowred) according to an increased NaOH concentration. SEM observation of the kenaf fibers showed that their crimps were developed and their surfaces were cleaned by the removal of protruding ends and impurities after alkali treatments. In the x-ray diffraction analysis, the structures of the fibers were found in the form of cellulose I when treated with a 0-16% alkali concentration and cellulose II when treated with over 20%. It was also confirmed that the crystallinity was lowered according to an increased NaOH concentration. The change of fiber compositions was investigated in FT-IR analysis. Strong band of $1,738cm^{-1}$ and asymmetrical stretching strong bands of $1,630-1,600cm^{-1}$ in spectrum (which represent pectin) were not found in the samples because the pectin was removed by the alkali treatment. Weak bands of $1,728-1,730cm^{-1}$ and peaks of $1,245-1,259cm^{-1}$ (which represent hemicellulose) and peaks of $1,592cm^{-1}$, $1,504cm^{-1}$, $1,462cm^{-1}$ and $1,429cm^{-1}$ (which are related to lignin) were not found or reduced in the samples treated with a concentration over 20%. TGA indicated that the kenaf fiber had the better hydrophilic properties by alkali treatment. The higher Tmax in TGA and the higher thermal stability when treated by alkali with the higher concentration. The fibers treated with an alkali concentration over 30% did not show any changes in Tmax.

• Journal of the Korean Society of Clothing and Textiles
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• v.14 no.1 s.33
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• pp.20-30
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• 1990

In order to investigate the mechanism of the formation of clothing microclimate with different blouse designs and materials, physiological and subjective sensational changes were measured. Experimental clothing were four types of blouse made of $100\%$ cotton, $100\%$ regular polyes­ter, and $100\%$ hygroscopic polyester. Four types of box style blouse were with stand collar and long sleeve, with stand collar and sleeveless, with long sleeve and collarless, and sleeveless and collarless. Five healthy female were chosen as subjects. Experiments were carried out in the environ­mental chamber controlled at $28{\pm}1^{\circ}C$ , $70{\pm}5\%$ RH. and still-air condition for SO min. The skin temperature (9 spots), oral temperature, humidity inside chest, and subjective sensations were measured. Obtained results are: I) Material which is capable of absorbing sweat effectively and transfering moisture rapidly made a comfortable feeling, because cloth­ing humidity is increasing slowly at this material. 2) During exercise period, covered arms have more influenced on thermal comfort than a covered neck.

• Journal of Nutrition and Health
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• v.12 no.3
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• pp.9-23
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• 1979

The known risk factors for atherosclerosis include plasma low density lipoproteins (LDL)or Cholesterol, low PUFA in the diet, hypertension, and high Na intake, obesity, diabetes, lack of exercise, cigarette smoking, sugar, low fiber and nicotinic acid in the diet, sources of Protein foods, and Psychological factors. Among various dietary factors, fat is known as the most serious causative agent for atherosclerosis. The genetic factor is a18o known as an important one but is out of scope in this paper. Since atherosclerosis is a progressive disease which may develop for many years before showing any definitive symptoms, it is very important to develop preventive programs especially in the country like Korea that is not quite overdevelopted as some western countries. In this paper all the factors mentioned above were reviewed and the dietary suggestion were made on the basis of the content of polyunsaturated and saturated fat in the diet to prevent or/and to cure this disease. Most of the available data on diet therapy with emphasis. on P/S ratio were tabulated together. after tile patient's habitual dietary intake is analized the guidelines of personalized fat-controlled diet can be recommended. It is of utmost importance to develop Korean diets for beth prevention and cure of atherosclerosis emphasizing individual eating habit in the near future which can be more Practicaly used both at home and in the hospital.

• Journal of the Korean Society of Clothing and Textiles
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• v.17 no.3
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• pp.347-358
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• 1993

Graft copolymerization of MMN4-VP onto cotton fiber using Ce(IV) salt as an initiator and triton X-100 as an emulsifier was performed under various polymerization conditions. In cograft polymerization, the polymeization behavior according to variation of 4-VP feed composition and the characteristics of MMA/4-VP graft polymer such as affinity for acid dye owing to cationization of cotton, antibacterial activity and thermal behavior were investigated. The results of this study were as follows : 1. While in copolymerization of MMA and 4-VP, 4-VP content in copolymer was more than that of monomer feed composition. 2. Increasing 4-VP content, graft yield was decreased, but graft efficiency was increased. In case of MMA/4-VP graft polymerization, the highest graft yield was obtained at higher CAN concentration than in MMA graft polymerization, the reason is that the behavior of 4-VP was disturbed by Ce(IV) sail 3. Elevation of temperature resulted in increase of graft yield and the apparent activation energy of MMA/4-VP graft polymerization was higher than that of MMA graft polymerization. 4. MMA/4-VP grafted cotton fiber showed affinity for acid dye, antibacterial activity and higher moisture regain than MMA grafted cotton fiber. MMA/4-VP grafted cotton fabric showed improvement of wrinkle recovery up to 40~50% graft yield and decreased thereafter. MMA/4-VP and MMA grafted cotton fabric did not showed significant difference in wrinkle recovery and stiffness.