• 한국표면공학회지
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• 제50권6호
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• pp.531-535
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• 2017

Enormous amount of waste oyster-shell (OS) has a major disposal problem in coastal regions. OSs have attracted much attention for recycling, because these are mainly composed of calcium carbonate with rare impurities. In this study, we demonstrate the calcareous deposit films on steel plate by using OSs on the basic of cathodic protection technique. The composition of the OSs was analyzed by wavelength dispersive X-ray fluorescence spectrometer. Carbon dioxide gas was pumped into distilled water to make carbonic acid solution for dissolution of OS. The calcareous deposit was characterized by second electron microscope (SEM), energy dispersive X-ray analysis (EDX) and X-ray diffraction. Corrosion rates were estimated by measurements of anodic polarization and immersion test. It is confirmed that calcareous deposits on steel plate are formed under all condition of cathodic protection by using waste OS from the SEM and EDX results. Calcareous deposits on steel by OS provide good corrosion resistance by acting as a barrier to oxygen supply to the steel surface.

• 에너지공학
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• 제21권1호
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• pp.47-54
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• 2012

정부는 에너지 절약시책의 일환으로 제1,2차 석유파동 후 1983년에 목동신시가지에 집단에너지 사업을 도입하였다. 이후 집단에너지산업의 공급규모는 꾸준히 증가추세를 보이고 있다. 이에 본 논문에서는 2009년도 산업연관표에 근거한 투입산출분석을 이용하여 집단에너지산업의 국민경제적 파급효과를 분석하고자 한다. 수요유도형 모형을 이용하여 집단에너지산업에서의 생산 혹은 투자가 다른 산업에 미치는 영향에 대하여 논의한다. 공급유도형 모형을 적용하여 집단에너지산업에서의 공급지장이 다른 산업에 미치는 효과에 대해 살펴본다. 레온티에프 가격모형을 이용하여 집단에너지산업의 가격 변동이 다른 산업의 산출물 가격에 미치는 영향에 대해 검토한다. 특히 집단에너지산업을 중심에 놓고 이를 외생화하여 분석하는 접근방법을 취했다. 분석 결과를 요약하자면, 집단에너지산업은 낮은 생산유발효과, 높은 공급지장효과, 낮은 물가파급효과, 낮은 전방연쇄효과, 낮은 후방연쇄효과를 가진다. 이러한 정량적 정보는 집단에너지산업을 위한 정책결정에 있어서 유용하게 활용될 수 있다.

• Nutrition Research and Practice
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• 제7권2호
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• pp.103-108
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• 2013

A folk prescription consisting of Alnus hirsuta, Rosa davurica, Acanthopanax senticosus and Panax schinseng has been used in the treatment of diabetes mellitus. The aim of the present investigation was to evaluate the antidiabetic effects of the herb formula extract (HFE) composed of Alnus hirsuta, Rosa davurica, Acanthopanax senticosus and Panax schinseng in the streptozotocin (STZ)-induced diabetic rats. The HFE was mixed in the food supply of the healthy and STZ-induced diabetic male Sprague-Dawley rats, and its effects on the body weight, water and food intake, hyperglycemia, hypolipidemic and islet structure were studied. The treatment of the rats with STZ for 6 weeks resulted in marasmus, polydipsia, polyphagia, hyperglycemia and hypoinsulinemia. In addition, the diabetic rats showed an apparent decrease in the insulin immunoreactivity and the number of ${\beta}$-cells in the pancreas. The addition of the HFE to the rats' food supply significantly lowered the serum glucose and the serum triglycerides level and preserved the normal histological appearance of the pancreatic islets. These results indicate that the HEF have a strong antidiabetic potential along with the significant hypoglycemic and hypolipidemic effects, which may be applicable in the pharmaceutical industry.

• 멤브레인
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• 제27권1호
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• pp.60-67
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• 2017

최근 전 세계적으로 급속한 도시화, 인구증가 및 기후변화에 따른 물의 수요와 공급의 불균형으로 인해 물 산업의 경제, 사회, 환경적 중요성은 더욱 증가하고 있다. 이러한 물 산업은 크게 해당 분야에 따라 사용되는 분리막의 종류가 상이하다. 주로 물리적, 화학적 안정성이 매우 우수한 고분자 소재가 사용되고 있으나, 이들 고분자들의 소수성인 성질 때문에 친수성을 부여하는 다양한 방법들이 소개되고 있다. 본 연구에서는 상용화되어 있는 중공사 지지체에 총 4종류의 친수성 고분자들을 도입하여 친수성을 부여하였고, 주사전자현미경을 통해 코팅된 중공사 지지체의 모폴로지를 확인하였다. 또한, 각 고분자들로 코팅한 중공사 지지체의 친수화 정도를 알아보기 위해 접촉각을 측정하였고, 마지막으로 코팅 시간에 따른 수투과도 변화 그리고 친수성 고분자에 따라 수투과도에 미치는 영향을 확인하였다. 그 결과 Pluronic 1 wt%로 코팅하였을 때 친수화 정도가 우수하며 중공사의 기공을 막지 않고 우수한 수투과도 정도를 나타내 수처리 분리막으로 가장 적절하다는 결론을 얻을 수 있었다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2009년도 춘계학술대회 논문집
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• pp.430-433
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• 2009

The development of large-scale environmental friendly livestock complex in the reclaimed tideland is one of different alternatives to increase the competitiveness of internal livestock industry against an international opening markets as DDA and FTA in agricultural field. Recently, it is possible to introduce an environmental friendly livestock complex in the reclaimed tideland by an amendment of the acts for agricultural land. However more studies that are on the basis of nitrogen and phosphorus mass balance need to preserve the agricultural environments as the quality of agricultural water and soil in rural area. In this study, the reference for feasibility study is Whaong reclaimed tideland which located at Whaseong city, Gyeonggi Province, and a basic concept of environmental friendly livestock complex is the production of forage crops with the supply of liquid fertilizer and the production of bioenergy such as biogas by the recycling of pig slurry as a resource. The mass balance of nitrogen based on between forage crops such as maize, barley and liquid fertilizer supplied at the reclaimed tideland, and also it was estimated an economical efficiency as anaerobic digestion plant for treating pig slurry of $100m^3/day$ introduce in an environmental friendly livestock complex.

• Asian-Australasian Journal of Animal Sciences
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• 제13권8호
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• pp.1162-1172
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• 2000

The research was conducted to quantify farm and household characteristics of sheep farmers, evaluate farmer access to and the effectiveness of livestock services in sheep farming areas, and examine regional constraints to improving sheep productivity and profitability in Nepal. A rapid diagnostic socioeconomic survey of 200 sheep farmers was carried out in 1996 and all four ecological regions (Trans-Himalayan, Mountains, Hills and Terai), each with a distinct local sheep breed, were represented in the survey. Six major constraints were identified: (a) poor performance of local sheep breeds, (b) a serious seasonal deficit of pasture and other feed, (c) the lack of an organized market for wool and meat, (d) poor access to agricultural credit, (e) primitive shearing equipment, and (f) an inadequate supply of drinking water for sheep. Strategies to assist farmers develop their sheep management skills, improve access and quality of support services, improved technology adaptable to local conditions and effective linkages with local carpet and meat industry are likely to overcome the constraints and alleviate persistent poverty faced by sheep farmers in Nepal.

• 한국수산과학회지
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• 제43권6호
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• pp.687-692
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• 2010

The mass cultivation of Ecklonia cava Kjellman was studied as a potential biomass source for the extract industry in Korea. Experiments were conducted to investigate the optimal conditions for artificial seed production and mass cultivation of this species. Maximum growth and young thalli development in the nursery culture area occurred at 2 m depth, whereas maximum growth of thalli in the main culture area occurred at 1 m depth. Production of E. cava was between 2.6 and 3.6 kg wet wt. $m^{-1}$ after depth control and removal of fouling organism, etc. The relationship between optimal water depth for culture and underwater irradiance during the E. cava cultivation was calculated as: y = -0.718x + 8.042 ($r^2$=0.976). The growth rates achieved in this trial indicate that E. cava cultures could produce and supply sufficient biomass.

• 한국조리학회지
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• 제10권4호
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• pp.1-14
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• 2004

This study investigates and analyzes the diversity of menu in military meal services that are recognized by the soldiers who are familar with meal services and, suggest the implications on the results of the analysis. For the ranks of respondents in terms of demographic features, the sergeants were 43.2%(186), the corporals were 29.7%(128). It was identified that the diversity of menu had significant influences as 57.5%. Thus, for the satisfaction on the kitchen and mess hall service, the sanitary condition was the most considerable factor as 41.6%. Next, water supply facilities, sewer hygiene and towels in washstaynds were the issues to be considered more. In conclusion, this study was limited only to the air soldiers in Chungcheon. Then, the future study needs to expand the samples more than this study to apply the results to the entire army. Moreover, the study could not be actively performed because of the particularity of the army. Consequently, it is required to make these kinds of researches dynamically performed like for any other meal service industries.

• Corrosion Science and Technology
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• 제10권2호
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• pp.60-64
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• 2011

Lean duplex stainless steels have been developed in Korea for the purpose of being used in the seawater systems of industry. There are also many important seawater systems in nuclear power plants. These systems supply seawater to cooling water condenser tubes, heat exchanger tubes, related pipes and chlorine injection systems. The flow velocity of some part of seawater systems in nuclear power plants is high and damages of components from corrosion are severe. The considered lean duplex stainless steels are STS329LD (20.3Cr-2.2Ni-1.4Mo) and STS329J3L (22.4Cr-5.7Ni-3Mo) and PRENs of them are 29.4 and 37.3 respectively. Physical, mechanical and micro-structural properties of them are evaluated, and electrochemical corrosion resistance is measured quantitatively in NaCl solution. Critical Pitting Temperatures (CPT)s are measured on these alloys and pit depths are evaluated using laser microscope. Long period field tests on these alloys are now being performed, and some results are going to be presented in the following study.

• 기술사
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• 제44권6호
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• pp.40-44
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• 2011

Nuclear energy in Korea began in 1958, when the Korea's atomic energy act was formulated and the relevant organizations were founded. Since then, notwithstanding the two catastrophe like TMI and Chernobyl accident, Korea made a wise decision to expand the peaceful uses of the nuclear energy as well as to localize the essential nuclear design technology of fuel and nuclear steam supply system. This decision resulted in the success of export of nuclear power plants as well as research reactor in 2010s. The Korea's nuclear policy, which well utilized 'international crisis in nuclear business' as 'opportunity of Korea to get. nuclear technology', is believed nice policy as a role model of nuclear new-comer countries. Based upon the success story of localization of nuclear technology, Korea had an eye for a niche market, which was a basis of development of SMART, Korea-made integral PWR. The operation of a SMART plant can sufficiently provide not only electricity but also fresh water for 100,000 residents. Last two years, Korea's nuclear industry team led by the Korea Atomic Energy Research Institute completed the standard design of SMART and applied to the Korea's regulatory body for standard design approval. Now the Korea's licensing authority is reviewing the design with the relevant documents, and the design team is doing its best to realize its hope to get the approval by the end of this year. From next year, the SMART business including construction and export will be explored by the KEPCO consortium.