• 한국정밀공학회지
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• 제20권4호
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• pp.143-150
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• 2003

Frictional properties of ultra-thin carbon coatings on silicon wafer were investigated based on Taguchi experimental design method. Sensitivity analysis was performed with normal load, relative humidity, deposition process, and coating thickness as the variables. It was found that despite low thickness, the carbon coating resulted in relatively low friction coefficient. Also, the frictional behavior was affected significantly by humidity and normal load.

• Carbon letters
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• 제6권3호
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• pp.148-157
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• 2005

Carbon/Carbon Composites due to their far superior thermo-mechanical properties are used in a number of demanding applications. However, the material still is used only in specific high tech applications with few exceptions in general industrial applications. The material is extremely expensive and the major challenge is to reduce its cost. Various innovative processing routes are outlined to reduce the cost of processing.

• KIEAE Journal
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• 제15권1호
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• pp.147-154
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• 2015

Environmental impact assessment techniques have been developed as a result of the worldwide efforts to reduce the environmental impact of global warming. By using the quantification method in the construction industry, it is now possible to manage the greenhouse gas is to systematically evaluate the impact on the environment over the entire construction process. In particular, the proportion of greenhouse gas emissions at the production stage of construction material occupied is high, and efforts are needed in the construction field. In this study, intended for concrete products for the construction materials, by using the LCA evaluation method, we compared the results of environmental impact assessment and carbon emissions of developing products that have been applied low-carbon technologies compared to existing products. As a result, by introducing a raw material of industrial waste, showed carbon reduction. Through a comparison of the carbon emission reduction effect of low-carbon technologies, it is intended to provide academic data for the evaluation of greenhouse gases in the construction sector and the development of low-carbon technologies of the future.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2001년도 The 6th International Symposium of East Asian Resources Recycling Technology
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• pp.215-219
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• 2001

Impurities removal from waste carbon black was carried out to produce high-grade carbon black. A lot of hydrophilic carbon black is produced as a byproduct of the hydrogen production process by flame decomposition of water. Due to its impurity content such as sulphur, iron, ash and etc., it can only be used as low-grade carbon or burnt out. High-grade hydrophilic carbon black is 3-5 times more expensive than oil-based carbon black because of its process difficulties and requires pollutant treatment. Hydrophilic carbon is normally used far conductive materials for batteries, pigment for plastics, electric wire covering, additives for rubber, etc.. In these applications, hydrophilic carbon must maintain its high purity. In this study magnetic separation, froth flotation and ultrasonic treatment were employed to remove impurities from the low-grade hydrophilic carbon black. As results, the ash, iron and sulphur content of product decreased to less than 0.01wt.%, 0.0lwt.% and 0.3wt.% respectively, and the surface area of product was about 930 $m^2$/g.

• 에너지공학
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• 제20권3호
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• pp.209-215
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• 2011

본 연구에서는 저온 열교환기 효율 향상을 위하여 상온($25^{\circ}C$)과 저온($10^{\circ}C$)에서 탄소나노유체와 산화탄소나 노유체의 열전도도와 점도를 측정하였다. 탄소나노유체는 다중벽 탄소나노튜브에 계면활성제 SDS 100 wt%, 고분자 화합물 PVP 300 wt%를 각각 혼합한 뒤 증류수에 초음파 분산하여 제조하였고, 산화탄소나노유체는 산화 처리된 다중벽 탄소나노튜브를 증류수에 초음파 분산하여 제조하였다. 탄소나노유체의 열전도도는 비정상 열선법을 사용하여 측정하였으며, 점도는 회전형 디지털 점도계를 사용하여 측정하였다. 그 결과 같은 혼합비율과 온도에서 다른 탄소나노유체들 보다 산화탄소나노유체의 열전도도가 가장 높게 측정되었고, 점도는 가장 낮게 측정되었다.

• 대한공간정보학회지
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• 제18권3호
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• pp.75-81
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• 2010

기존의 자전거 도로에 대한 연구는 대부분 자전거 도로의 신설을 통하여 활성화하기 위한 연구가 대부분이었다. 그러나 점차 자전거 도로의 이용자가 증대됨에 따라 녹색 교통수단으로서의 자전거 이용을 활성화하기 위해서는 저탄소 녹색성장 기반의 서비스가 필요한 실정이 되었다. 기존의 자전거 이용정보의 분석은 주로 운동량에 기반하고 있어 사용자의 다양한 요구사항을 수용하고 있지 못하고 있다. 따라서 본 연구에서는 자전거를 이용함으로서 절감할 수 있는 이산화탄소, 유류비, 지구온난화 처리비용 등을 계산할 수 있는 방법을 제안하였다. 이를 위해 GPX(GPS eXchange Format) 파일형태로 제공되는 자전거 이용정보를 구글어스 기반의 3차원 환경에서 디스플레이하고 저탄소 녹색성장 기반의 서비스를 할 수 있는 프로그램을 구현하였다. 개발된 응용프로그램은 기존의 상업용 소프트웨어와 비교하였다. 본 연구를 통해서 자전거 이용자 측면에서 저탄소 녹색성장을 실천할 수 있는 서비스를 개발하였으며 스마트폰과 같은 단말기에도 적용할 수 있을 것으로 사료된다.

• 한국환경보건학회지
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• 제23권2호
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• pp.24-27
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• 1997

This study has been designed to check the removal effect of contaminated water by various water treatmemt processes using sediment filter, activated carbon, reverse osmosis membrane, ultra vilolet sterilizer and ultra filtration and then to analyze the change of pH, the concentration of chlorides, bacteria and E. coli. after 24 hours. pH has increased as much as 0.15-0.32 by activated carbon but decreased sharply by reverse osmosis treatment after 24 hours. The removal effect of chloride was low by activated carbon and ultra filter but high in reverse osmosis. The removal effect of bacteria and E. coli was low by activated carbon and membrane filter system using activated carbon. Ultra filtration process was effective for purify agricultural water containg bacteria and E.coli.

• Carbon letters
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• 제1권2호
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• pp.82-86
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• 2000

The present research was undertaken to evaluate the possibility of water purification filter with activated carbon fibers (ACFs) using a very low cost precursor consisting of phenolic resin coated on glass fibers. The simplified procedure involving coating, curing and activation and a very low cost glass fiber as a raw material were adopted in order to reduce manufacturing cost. The breakthrough curves of the manufactured ACFs and the commercial activated carbon (AC, Calgon F-200) were investigated in the initial concentration range from 19 to 49 ppm for benzene, toluene and ethylbenzene. From breakthrough profiles, the manufactured ACFs had significantly faster adsorption kinetics than the AC. Especially the benzene breakthrough curves, the manufactured ACF (13 g of ACF with 32% of carbon on the glass) was over the limited level (5 ppb) after flowing of 32 l at initial concentration of 15 ppm, while the commercial AC was shown about 3 ppm in initial adsorption.

• 한국지역지리학회지
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• 제20권1호
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• pp.70-91
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• 2014

세계 각국은 기후변화에 대응하기 위한 노력을 기울이고 있으며, 우리나라 또한 예외가 아니다. 세계의 저탄소 녹색도시가 고유한 모델과 실천전략을 통해 다양한 모습으로 실행되어 왔음에 비추어, 우리나라 또한 우리나라의 풍토와 지형적 특성에 맞는 한국형 녹색도시의 모델 및 실천 전략이 필요하다. 이에 본 연구는 우리나라의 전통적인 공간 사유체계인 풍수에 주목하여, 풍수 논리의 현대적 해석을 통해 한국형 녹색 도시 조성 방안을 고찰하고자 한다. 이를 위해, 우선 과거 도시 및 전통마을과 현대 도시의 차이점을 파악하여, 과거의 풍수 논리를 현대 도시의 관점에서 재해석한다. 풍수 논리의 현대적 해석을 바탕으로, 풍수논리에 담겨 있는 입지선정과 공간계획 체계가 한국형 녹색도시 조성에 어떻게 적용될 수 있는지를 모색하고자 한다.

• 한국재료학회지
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• 제30권4호
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• pp.184-196
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• 2020

In this study, effects of carbon and nickel on microstructure and low temperature Charpy impact properties of HSLA (high strength low alloy) steels are investigated. To understand the complex phase transformation behavior of HSLA steels with high strength and toughness before and after welding processes, three kinds of HSLA steels are fabricated by varying the carbon and nickel content. Microstructure analysis, low temperature Charpy impact test, and Vickers hardness test are performed for the base metals and CGHAZ (coarse-grain heat affected zone) specimens. The specimens with the lowest carbon and nickel content have the highest volume fraction of AF, the lowest volume fraction of GB, and the smallest GB packet size. So, the low temperature Charpy absorbed energy of the CGHAZ specimen is the highest. The specimens with increased carbon and nickel content have the lowest volume fraction of AF, the highest volume fraction of GB, and the largest GB packet size. So, the low temperature Charpy absorbed energy of the CGHAZ specimen is the lowest.