• Journal of the Korean Society for Geothermal and Hydrothermal Energy
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• v.8 no.3
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• pp.19-28
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• 2012

In a heat only boiler system of a steam power plant, outdoor air required for combustion is made to pass through indoor space for increasing the boiler efficiency. Due to heat generated by various equipments, temperature of the air that enters the boiler will increase resulting in combustion efficiency. If the outdoor air temperature is low, however, this will cause freezing and bursting of pipes which are filled with water. It is especially fatal to small diameter pipes and pipes connected to measuring instruments. The purpose of this study is find operation and outdoor conditions where this phenomena can happen and also establish preventive measures to avoid this problem.

• Proceedings of the KAIS Fall Conference
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• 2007.11a
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• pp.337-340
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• 2007

냉간단조금형(Cold Forging Die)의 다이블록(Dieblock)을 제작하는 방법 중의 하나로, 다이블록 제작용 재료를 면가공 하여 다이블록 상면(上面)을 마스터펀치(Master Punch)인 호브(Hob)로 압입(Indentaion) 시켜 절삭가공((Cutting Work)이 아닌 다이호빙(Die Hobbing) 방법으로 임프레션(Impression)을 성형하여 제작하고 있다. 이 방법에 의하여 다이블록의 재료를 합금공구강(Alloy Tool Steel)인 SKD11을 사용하여 제작하고, 스테인리스판(Stainless Sheet Metal)을 제품 재료로 하여 냉간단조가공(Cold Forging Work)을 하였더니 6,000 스트로크(Stroke)에서 금형수명(Die Life)을 다 하였다. 본 논문에서는 다이블록 재료를 고속도공구강(High Speed Tool Steel)인 SKH51로 교체 제작하고, 탄소강(Carbon Steel)인 S45C를 제품 재료로 하여 냉간단조가공을 수행 하였더니 21,000 스트로크에서 금형수명을 다하고 종료 되어 종래의 방법과 비교 검토 하였을 때 350%의 금형수명 연장 효과를 얻게 되었다.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.12 no.1
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• pp.63-73
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• 2006

The first packaging of Korean market milk dates back to July 1937 when Seoul Dairy Co-operative (Kyung Seong Dairy Co-operative in those days) used 1 hob (180 ml) glass bottles with either paper caps or cork caps. During 1945-1972, 2 hob (360 ml) glass bottles were produced, and iron caps and egret-shaped plastic film replaced the previously used caps. When there were insufficient numbers of milk bottles, other glass bottles such as soda drink bottles and beer bottles were used instead. Seoul Dairy Co-operative was the only dairy company existing in Korea until Nam Yang Dairy Co. Ltd was founded in March 1964, followed by Hae Tae Dairy Co. Ltd(Tae Han Food Public Corporation in those days) in 1969 and Mae-il Dairy Co. Ltd (Korea Dairy Company in those days) in May 1971. As many other dairy companies along with the above-mentioned companies were established, a variety of dairy products were packaged and marketed. In 1971 Seoul Dairy Co-operative first used triangular-shaped polyethylene film wrappers, and in 1972 Nam Yang Diary was the first company importing sterilized Tetra pak for the packaging of milk. Since 1974 rectangular shaped polyethylene film wrappers and plastic bottles were used. In 1977 the gable top carton pack made of paper was first introduced by Seo Joo Industry Co. Ltd, and its market share increased rapidly with gradual increase in its volume, from 180ml to 200ml, to 250ml, to 500ml and finally to 1,000ml, causing change in the volume of milk consumption. And in Sep. 1987 Pasteur market milk Co. Ltd. first used round type high density polyethylene bottle(body) with low density polyethylene cap of 245g, 490g and 980g volumes respectively.

• The Journal of Internal Korean Medicine
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• v.30 no.4
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• pp.746-760
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• 2009

Objectives : This study was designed to evaluate the effect of Hasuogamibang (HGB) on hyperlipidemia and antioxidant activity. Methods : For this study, we divided four groups of rats (normal WKY group, normal SHR group, high cholesterol diet and saline-treated SHR group, high cholesterol diet and HGB-treated SHR group), and observed the change of body weight, weight of liver, cholesterol, triglyceride, glucose, albumin, histologic change of liver and aorta, lipid peroxidation and antioxidant activity of liver tissue, and cholesterol gene revelation control efficiency. Results : Total-cholesterol, LDL-cholesterol, triglycerides were decreased significantly by HGB. However, HDL-cholesterol increased significantly. The tissue of liver and aorta were controlled defect by HGB on histologic study. Lipid peroxidation and SOD of liver tissue was decreased significantly by HGB. Gene revelation of ACAT and HMG CoA reductase in hepatic tissue was decreased significantly by HGB. Conclusion : This study suggests that HOB is significantly effective on hyperlipidemia and antioxidant activity.

• Journal of the East Asian Society of Dietary Life
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• v.10 no.6
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• pp.465-479
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• 2000

The ${\ulcorner}$Ganpyun Chosun Yori-Jebup${\lrcorner}$, was written in Korean in 1934 The analytical results on this book were as follows :1. Fermentation foods were Kimchi, Jut, Jang and Cho. There were 19 kinds of Kimchi with 32materials, 3 kinds of Jut with 4 materials. 8 kinds of Jang with 25 materials and 1 kind of Cho with4 materials.2. There were 47 kinds of DDug(Korean rice cake) with 38 materials.3. Hangwa included Yumilgwa, Suksilgwa, Kangiung, Dasik, Jungwa, and Gwapyun. There were 6 kinds of Yumilgwa with 18 materials. 4 kinds of(Suksilgwa with 7 materials, 6 kinds of Kangjung with 10materials, 7 kinds of Dasik with 14 materials, 13 kinds of Jungwa with 21 materials, and 3 kinds of Gwapyun with 6 materials.4. Korean Beverage included Hwachae and Cha(Korean Tea) . There were 12 kinds of Hwachae with 39materials and 4 kinds of Cha(Korean tea) with S materials.5. Nambi and Sot were used as utensil.6. The measuring units were 'mal', 'sul', 'doi', 'hob', 'ryang', 'geun', 'pun' etc. The foods were prepared frequently by "shaking" and heated by "steaming" .uot;steaming" .ot; .

• The Magazine of the Society of Air-Conditioning and Refrigerating Engineers of Korea
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• v.29 no.1
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• pp.48-56
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• 2000

한국지역난방공사는 '87년 여의도에 최초 연공급을 시작한 이래 수도권 신도시 및 서울 강남 지역을 중심으로 지역난방 열공급을 지속적으로 확대하여 왔다. 안정적이고 경제적인 역공급을 위하여 분당, 고양 및 중앙의 CHP를 중심으로 연계배관망을 구성하였으며 '98년 기준 수도권 연계 공급량이 총 공급량의 61%를 차지하게 되었다. 또한 장기적으로 본 공사는 열공급의 신뢰성 및 경제성 향상을 위하여 급열센타 설치를 비롯하여 종합적인 네트워크를 구성하여 운영할 계획이며 분당과 고양의 CHP를 기저부하로 삼아 피크수요를 감당할 소규모 분산형 열원을 설치하여 수도권 열공급을 확대하여 전 수도권을 지역난방 배관으로 네트워크화할 계획을 가지고 있다. 따라서, 구체적인 세부계획을 수립하기 위하여는 수도권 네트워크 사업의 장기적인 경제성 분석이 필수적이며 이러한 분석은 기존의 열원 및 열배관시설은 물론 향후 건설될 열원 및 배관, 수요개발전망 등 제반요소를 고려하여 종합적으로 이루어져야 하다. 본 연구는 이에 앞서 분당과 일산CHP를 독립된 수용범위를 갖는 열원으로 간주하여 각각의 CHP를 중심으로 열공급량의 증가에 따라 피크용 열원인 HOB 건설을 증가시킬때의 경제성을 그 대상으로 하여 기본적인 모델을 제시하고 대략적인 추세를 파악하고자 하였다. 데이터는 본 공사 고양지사와 분당지사의 '98 운영실적으로 기준으로 하였으며, 수도권 전체 네트워크를 대상으로 하는 실제 경제성 분석은 다음 과제로 계속 추진될 것이다.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.37 no.8
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• pp.1029-1033
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• 2013

Elliptical gear is used as a rotor of oval flowmeter. The elliptical gear can assist water flow-rate measurement by the space of the elliptical shape. Presently, elliptical gears have been processed using hob tool imported from Japan. But if it were not for the technical cooperation with Japan company, the Elliptical gears can't be processed. The purpose of this study is developing a domestic technology for elliptical gears and overcoming the dependence of foreign technical skills. It will bring the import substitution effect. In case of pressure angle $20^{\circ}$, the elliptical gears have an interference of tooth. The increase of pressure angle makes the root of a tooth thick and the top of tooth thin. By results of this study, tooth of elliptical gear was designed and verified through the 2D and 3D simulation.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.2
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• pp.281-285
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• 2008

Die hobbing is one of the dieblock manufacturing methods of cold forging die, which makes the upper side of dieblock indented using master punch, hobb to produce impression not using cutting work. SKD11, alloy tool steel was used as the material of dieblock and stainless sheet metal was used as product material in cold forging work. The life span of the die was 6,000 strokes. In this research, the material of dieblock was changed into SKH51, the high speed tool steel and the product material was S45C, the carbon steel in the cold forging work. The life span of the die was 21,000 strokes, which is 350% of the life span of the die using the former method.

• Journal of Korean Society on Water Environment
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• v.21 no.2
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• pp.125-131
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• 2005

Natural organic matter(NOM) is defined as the complex matrix of organic material and abundant in natural waters. It affects the performance of unit operations for water purification. Several kinds of analytical indicators such as DOC, specific ultraviolet absorbance(SUVA), apparent molecular weight (AMW), fractionation and high performance size exclusive chromatography(HPSEC) have been used to understand characteristics and variations of NOM. This study aims to evaluate the characteristics of NOM in the Geum River system comprising with stream flows and reservoirs. It was identified that SUVA denoting the portion of humic substance in water ranged within 1.60~3.36. Using resin adsorbents, dissolved organic carbon(DOC) was fractionated into three classes: hydrophobic bases(HOB), hydrophobic acids(HOA) and hydrophilic substances(HI). HI dominates in all samples, collectively accounting for more than 62% of the DOC. HOA was the second dominated fraction and it varied considerably but accounted for about 30% of the DOC. The distribution of high molecular weight(HMW) measured by HPSEC being used to determine the molecular weight distribution of aquatic humic substances was 40.1% and 38.7% in reservoir and stream flow, respectively. The distribution of low molecular weight(LMW) in stream flow was 13.2% higher than that in reservoir. And apparent molecular weight less than 1KDa, which include the molecular weight of hydrophilic organic matter, occupied with 69.2% and 68.2% in stream flow and reservoir, respectively. While the molecular weight of 1 to 100 KDa including humic substances ranged with 18.6% and 21.6% in stream flow and reservoir, respectively. Seasonal variation of refractory dissolved organic carbon was similar to that of SUVA.

• Journal of the Korean Institute of Landscape Architecture
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• v.23 no.1
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• pp.123-139
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• 1995

The megalopolis citizens are reevaluating the expectant value and the perception of leisure aceording to increasing the level of their incomes, The leisure of citizens is increasing in the aspect of quantity and quality of life nowadays In the site planning of leisure, the concrete understanding about people's choice of a leisure site will be the most important thing, not only for the aspect of improvement of the quality of life but also efficiencies of the land use The purposes of chi study are firstly, to find out the factors which are influenced on a choice of Outdoor leisure facilities in neighbourhood unit and to Compare the Characteristics Of Choice models between the three metropolitan areas, secondly, to predict a limitation of use areal according to the change of a needed time based on the metropolitan's standard choice model For the choice model establishment this research used Logit Model which has been used in the field of the traffic, the tourism and the economics. This research made the results which find out the influencing variables with needed times, the accessibility and the percentage of facilities. The lindtations of use areas come out the results which are predicted according to the change of needed times as a most influencing factors. The range of each preferred leisure facility is about 956 meter distant in the neighbourhood park about 644 meter distant in the pocket park about 604 meter distant in the recreation center, about 628 meter distant in the tennis court about 974 meter distant in the private hob by facility and about 528 meter distant in the library from the apartment unit The recreation center and the library are nearer facilities than the other facilities. But these facilities are surveyed to be more or less influenced by an interesting progran, a context of events and the level of useful facilities, etc.