• Carbon letters
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• 제4권2호
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• pp.57-63
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• 2003

In polymer precursor based activated carbon, the structure of starting material is likely to have profound effect on the surface properties of end product. To investigate this aspect phenolic resins of different types were prepared using phenol, mcresol and formaldehyde as reactants and $Et_3N$ and $NH_4OH$ as catalyst. Out of these resins two resol resins PFR1 and CFR1 (prepared in excess of formaldehyde using $Et_3N$ as catalyst in the basic pH range) were used as raw materials for the preparation of activated carbons by both chemical and physical activation methods. In chemical activation process both the resins gave activated carbons with high surface areas i.e. 2384 and 2895 $m^2/g$, but pore size distribution in PFR1 resin calculated from Horvath-Kawazoe method, contributes mainly in micropore range i.e. 84.1~88.7 volume percent of pores was covered by micropores. Whereas CFR1 resin when activated with KOH for 2h time, a considerable amount (32.8%) of mesopores was introduced in activated carbon prepared. Physical activation with $CO_2$ leads to the formation of activated carbon with a wide range of surface area (503~1119 $m^2/g$) with both of these resins. The maximum pore volume percentage was obtained in 3-20 ${\AA}$ region by physical activation method.

• 대한한의진단학회지
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• 제17권3호
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• pp.215-223
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• 2013

Objectives Although tongue diagnosis is one of major diagnostic methods in east Asian traditional medicine, the standard of normal tongue color have not established. So we tried to suggest the method to establish the standard of normal tongue color range and the pilot data about the normal range. Materials and methods: 22 precedent study papers that presented the numerical data of normal (light red) tongue color were analyzed. At the same time, 46 adult people tongue color data were also collected and analyzed. Results Precedent studies showed remarkable fluctuations of the range of normal tongue color. Collected tongue color data of the 46 people showed mean Hue value 2 and standard deviation 14 in HSB system. Additionally, 3 ways of standard establishment for normal tongue color were suggested. Conclusion We suggest statistical method as a reasonable method for tongue color standard establishment and $2{\pm}14$ as a reference Hue value for normal tongue color.

• 건축사
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• 통권597호
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• pp.120-127
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• 2018

• Carbon letters
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• 제4권3호
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• pp.126-132
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• 2003

Granular Activated Carbon (GAC) has been proven to be an excellent material for many industrial applications. A systematic study has been carried out of the kinetics of physical as well as chemical activation of phenolic resin chars. Physical activation was carried out using $CO_2$ and chemical activation using KOH as activating agent. There are number of factors which influence the rate of activation. The activation temperature and residence time at HTT varied in the range $550{\sim}1000^{\circ}C$ and $\frac{1}{2}{\sim}8$ hrs respectively. Kinetic studies show that the rate of chemical activation is 10 times faster than physical activation even at much lower temperature. Above study show that the chemical activation process is suitable to prepare granular activated carbon with very high surface area i.e.$ 2895\;m^2/g$ in short duration of time i.e. 1 to 2 hrs at lower temperature i.e. $750^{\circ}C$ from phenolic resins.

• Carbon letters
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• 제16권1호
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• pp.19-24
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• 2015

The breakthrough behaviour of activated charcoal cloth samples against an oxygen analogue (OA) of sulphur mustard has been studied using the modified Wheeler equation. Activated charcoal cloth samples having different surface area values in the range of 481 to $1290m^2/g$ were used for this purpose. Breakthrough behaviour was found to depend on the properties of the activated charcoal cloth, properties of the OA and the adsorption conditions. Activated charcoal cloth with a high surface area of $1290m^2/g$, relatively large surface density of $160g/m^2$ and coarser fiber structure exhibited better kinetic saturation capacity value, 0.19 g/g, against OA vapours when compared to others, thus confirming its potential use in foldable masks for protection against chemical warfare agents.

• 한국농공학회논문집
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• 제52권2호
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• pp.59-66
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• 2010

This study was performed to develop the embankment protection method that can reduce demage by prevention of embankment loss and collapse from overflow due to heavy rain and flood. For overflow test, model dam was prepared and embankment behaviors were monitored with the established piezometer and strain meter during overflow. As a result of overflow test for model dam, in case of embankment without waterproof mat, the lower end of embankment was collapsed within 40 seconds after beginning of overflow. On the other hand, in case of embankment with waterproof mat, embankment collapse didn't occurred during overflow. Accordingly, establishment of waterproof mat for embankment showed that be absolutely effective for the embankment protection during overflow in reservoir. Also, it showed that the minimum establishment range of waterproof mat to prevent embankment collapse in reservoir is from maximum storage level to the lower end of embankment.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 추계학술발표대회 논문집
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• pp.376-382
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• 2011

Since the Industrial Revolution has caused global change by using of a fossil fuel, a reckless and growth-oriented development. A global mean temperature since 19th century has climbed up 0.4~$0.8^{\circ}C$. Our country, afterwards, global warming has increased the temperature every season. After The Kyoto Protocol regarding a greenhouse gas reduction goal took effect, be situations that decrease of greenhouse gas was acutely required. Therefore, interest of utilization of the new & renewable energy is increasing everyday. In advanced research, we shows that at first divided a country to nine range by natural geography, and second executed Meteorological data analysis of recent 30 years considering level of significance by nine range. The results of advanced research are that the similarities are low because there are the regions that temperature deviation of the similar climate regions is large in winter season, and there are not characteristics of clear discrimination of temperature. This study shows that at first divided a country to six range by temperature range, and second executed Meteorological data analysis of recent 30 years considering level of significance by six range. The results of this study are that in heating load calculation of building, periodic temperature data management is required because facility capacity and cost are affected greatly by outdoor temperature, and temperature by climate range needs consideration of pertinent area. Ground temperature was assumed of the weather in region, the ground and soil. Lastly, we were able to know that establishment of climate region by temperature range can be useful policy making and plans of design of the horticultural facilities and architectures.

• 융합보안논문지
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• 제13권5호
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• pp.197-205
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• 2013

사회안전과 질서유지를 위하여 Security를 연구하는 학문이다. 비록 산업계에 비하여 18년이라는 짧은 기간이지만, 다방면의 학자들이 이 분야에 관심으로 가지고 많은 노력을 해왔다. 그러나 지금의 경호학은 몇 가지 문제점들을 안고 있어서 학문으로써의 가치를 인정받기 어려운 실정이다. 이를 위해서 몇 가지 선결과제가 해결이 되어야 한다. 첫째, 학문적인 개념과 범위 설정에 대한 산학간의 합의점 마련. 둘째, 모호한 학문의 정체성을 확립하기 위한 학적체계의 정립. 셋째, 교육체계의 정비부족을 극복하기 위한 교육체계 정립 방안의 마련. 넷째, 산업계와 상이한 연구방향에 대한 비가시성을 극복하기 위한 방안 등을 들 수 있다. 따라서 이 연구는 경호학이 학문으로써의 정체성과 가치를 높이기 위하여 네 가지 선결과제를 중심으로 그에 따른 대안을 제시하도록 하는데 목적을 두었다.

• 한국교육논총
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• 제39권1호
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• pp.1-13
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• 2018

본 연구는 도행지의 대표적인 교육실천인 학교 설립 및 운영 과정에 대한 분석을 통하여 도행지의 학교교육관에 대해 살펴보았다. 도행지는 교육기회의 확대를 위하여 다양한 형식의 학교를 설립하고 운영하였다. 이 학교들은 교육대상의 보편화를 위한 도행지의 교육실천으로 전인교육을 위한 교육목표 하에 생활교육론에 입각한 교육내용으로 교사와 학생의 역할분담을 최소화한 "교학주합일"의 교수학습방식을 취하고 있다. 또한 학교 운영에서 학칙과 각종 제도를 통한 제도화 관리와 학생 자치를 통한 민주화 관리를 실시하였다. 이러한 도행지의 교육실천은 학교교육의 교육대상, 교육목표, 교육내용, 교육방법 및 학교 운영의 본질적인 변혁을 일으켰으며 현대 학교교육의 발전에도 중요한 시사점을 제공하고 있다.

• 한국추진공학회:학술대회논문집
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• 한국추진공학회 2006년도 제26회 춘계학술대회논문집
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• pp.177-180
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• 2006

엔진시스템의 설계와 시험을 위해 엔진의 작동 영역을 설정하여 설계하고 이를 확인하기 위한 시험을 수행하는 것이 필요하다. 국내 액체 로켓 엔진 개발에 활용하기 위한 기초 자료를 목표로 일본, 미국, 유럽, 러시아의 액체로켓엔진 작동영역과 인증시험을 위한 성능 영역을 조사하였다.