• 한국식품영양과학회지
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• 제22권1호
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• pp.96-100
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• 1993

잣 지방질을 정제 단계를 달리하여 자동산화 시키면서 토코페롤 및 카로티노이드의 변화를 살펴 보았다. 정제 단계를 거칠수록 산화 안정성이 감소되었으며 총 토코페롤의 함량은 조지방의 경우 55.51mg/100g oil이었으며 이 중 $\alpha$-토코페를 25.48mg, ${\gamma}$-토코페를 23.94mg, $\beta$-토코페를 6.99mg순으로 함유되어 있었으며 $\delta$-토코페롤은 흔적량 존재하였다. 탈검된 지방질 및 탄산된 지방질에서도 $\alpha$-토코페를이 23.85mg, 24.08mg, ${\gamma}$-토코페롤이 19.79mg, 20.04mg, 그리고 $\beta$-토코페롤은 6.12mg, 5.33mg함유되어 있었다. 카로티노이드 중 $\beta$-카로틴은 비 비누화물질 중의 0.63%이었으며 리코펜은 미량 함유되어 있었다. 지방질의 자동산화가 진행되는 동안 카로티노이드와 토코페롤은 감소되었으며, 특히 자동산화의 초기과정에서 항산화제로 작용하여 상당량이 감소된 것으로 여겨졌으며 그 감소속도는 $\alpha$-토코페롤, ${\gamma}$-토코페롤 순이었다.

• Journal of Radiation Protection and Research
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• 제40권3호
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• pp.155-161
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• 2015

Radon is a naturally occurring radioactive gas and a major indoor contribution of exposure to ionizing radiation in dwellings. $^{222}Rn$ is a health hazard gas what is responsible for thousand lung cancer deaths every year. In this study, indoor radon concentrations present in thirty representative houses in Mahallat city, Iran, were determined in order to estimate lung cancer risk associated with residential radon exposure. Long-term passive method, using CR-39, was used to measure the radon concentration. The results showed an association between the age of the dwellings and the indoor radon concentration that was found, in that the concentration of radon tended to increase as the age of the dwelling also increased. The indoor radon concentrations were calculated to be within the range of $23{\pm}2$ to $350{\pm}26Bq{\cdot}m^{-3}$, with an average of $158Bq{\cdot}m^{-3}$. The annual effective dose from inhaled radon and its decay products was calculated between $0.8{\pm}0.1$ and $12.3{\pm}0.9mSv{\cdot}y^{-1}$, with an average of $5.5mSv{\cdot}y^{-1}$. By taking into consideration the EPA recommendation and ICRP statement, the average annual risk of lung cancer from inhaled radon was calculated as 0.09%, 0.06%, 0.01%, and 0.03% for current smokers (CS), those who had ever smoked (ES), never smokers (NS) and the general population, respectively.

• 펄프종이기술
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• 제47권2호
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• pp.61-69
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• 2015

A number of researches have been carried out regarding the utilization of nanocellulose(crystalline nanocellulose, microfibrillated cellulose, nanofibrillated cellulose) for the manufacture of various kinds of composites and functional products. However, only few research works on the manufacturing characteristics of nanocellulose could be found, although some companies started already the production of nanocellulose in commercial scale. However, the most important thing in commercializing of production and utilization of nanocellulose is to develop the economical and efficient process. Thus, this study was carried out in order to investigate the effects of refining, alkaline pre-treatment and grinder clearance on the characteristics of microfibrillated cellulose and energy consumption. There was no significant differences in crystalline index with the degree of microfibrillation. The initial fibrillation could be improved by refining pre-treatment, but its effect was not observed anymore since the fibrillation was done up to certain level by grinding. Refining pre-treatment did not improved the energy efficiency. Alkaline pre-treatment can be helpful because the swelling of pulp fiber will facilitate fibrillation. It was found that the decrease in grinder clearance was helpful to improve the energy efficiency.

• 한국식품영양과학회지
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• 제21권2호
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• pp.175-180
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• 1992

말쥐치 가공 중 폐기되고 있는 말쥐치 내장중의 지질을 보다 효율적으로 이용하기 위해 탈검, 탈산, 탈색 및 탈취 등 말쥐치 내장유의 정제조건에 대하여 검토하였다. 말쥐치 내장유 100$m\ell$에 대하여 4% 옥살산을 20$m\ell$ 첨가하고 이어서 6$0^{\circ}C$에서 15분간 교반하여 탈검한 다음 이것에 4M의 알칼리 용액을 계산량 보다 0.5% 과잉으로 첨가한 후 6$0^{\circ}C$에서 30분간 탈산 처리하는 것이 효과적이었다. 탈산처리한 말쥐치 내장유의 10%에 해당하는 산성 백토를 첨가하고 감압하에 6$0^{\circ}C$에서 20분간 탈색 처리한 후 압력을 4 torr 이하로 유지하면서 수증기 증류법으로 18$0^{\circ}C$ 에서 60분간 처리한 말쥐치 내장유가 물리, 화학적 성상이 가장 우수하였다.

• 문화기술의 융합
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• 제9권6호
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• pp.935-940
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• 2023

인공지능과 빅데이터 분석을 위해 웹 스크래핑으로 수집된 대부분의 텍스트 데이터들은 일반적으로 대용량이고 비정형이기 때문에 빅데이터 분석을 위해서는 정제과정이 요구된다. 그 과정은 휴리스틱 전처리 정제단계와 후처리 머시인 정제단계를 통해서 분석이 가능한 정형 데이터가 된다. 따라서 본 연구에서는 후처리 머시인 정제과정에서 한국어 딕셔너리와 불용어 딕셔너리를 이용하여 워드크라우드 분석을 위한 빈도분석을 위해 어휘들을 추출하게 되는데 이 과정에서 제거되지 않은 불용어를 효율적으로 제거하기 위한 "사용자 정의 불용어 시소러스" 적용에 대한 방법론을 제안하고 R의 워드클라우드 기법으로 기존의 "불용어 딕셔너리" 방법의 문제점을 보완하기 위해 제안된 "사용자 정의 불용어 시소러스" 기법을 이용한 사례분석을 통해서 제안된 정제방법의 장단점을 비교 검증하여 제시하고 제안된 방법론의 실무적용에 대한 효용성을 제안한다.

• Journal of the Korean Wood Science and Technology
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• 제15권3호
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• pp.24-33
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• 1987

This study was executed to investigate scanning electron microscopic characteristics of Korean Rhus lacquer coats. With the unrefined coat, distilled water, sodium hydroxide, acetic acid, ethyl alcohol, cold-check test, and accelerated weathering were performed after refining treatment. These treated lacquer coats were discussed through observation by scanning electron microscope and the obtained results were summarized as follows: 1. Compared with unrefined coat, the refined coat of Korean Rhus lacquer showed more even surface with regular distribution of dispression. 2. Korean Rhus lacquer coat heated at $120^{\circ}C$ for 3 hours revealed no observable difference irrespective of refining and unrefining. 3. Korean Rhus lacquer coat treated by distilled water, sodium hydroxide, acetic acid. ethyl alcohol, cold-check test. and ultraviolet radiation showed significant characteristics compared with untreated coat. Especially. large deformation and checkings were observed by cold-check test and ultraviolet radiation respectively. 4. The Korean Rhus lacquer coat radiated by ultraviolet ray showed 0.11 duller and 1.41 brighter than non-radiated coat through color difference calculator.

• E2M - 전기 전자와 첨단 소재
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• 제7권2호
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• pp.130-137
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• 1994

Indium, element of group III, was refined by using zone refining for high purity refinement. We have found the impurities of T1, Zn, Fe, Cd, Pb, Ni, Cu, Sn in the refined indium with ICP-AES, so that 3.9 weight ppm of T1 was reduced to less than 1 ppm, 1.0 weight ppm of Zn was reduced to 0.7 ppm, 2.8 weight ppm of Cd was reduced to 2.5 ppm and 14.0 weight ppm of Sn was reduced to 6.7 ppm with 5 melten zone passes only. 3.9 weight ppm of T1 was reduced to less than 1 ppm, 1.0 weight ppm of Zn was reduced to 0.3 ppm, 2.8 weight ppm of Cd was reduced to less than 1.0 ppm and 14.0 weight ppm of Sn was reduced to 0.4 ppm after vacuum baking with 5 melten zone passes. The surface morpholgy of metal Indium thin film in each conditions showed that porosities were reduced in the front of sampled ingot after vacuum baking with 5 zone melten zone passes. The average electrical resistivity of Indium thin film was reduced from 1.4*10$^{-3}$ .ohm.-cm in Indium origin ingot to 7.9*10$^{-6}$ .ohm.-cm after zone refined with 5 melten zone passes.

• 한국세라믹학회지
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• 제42권7호
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• pp.483-489
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• 2005

For the raw materials of 3CaO$\cdot$3Al$_{2}$O$_{3}$ $\cdot$CaSO$_{4}$(CSA) clinker manufacturing, the applications of industrial wastes such as waste shell, spent oil-refining catalyst and desulfurized gypsum were examined. The c1inkerbility of the raw mix and the behaviour of formation of clinker minerals were studied and then some hydraulic properties of cements containing the clinker were also investigated. By virtue of the high reactivity of thermally decomposed raw materials, CSA clinkers were obtained at relatively low temperature of 1250$^{\circ}C$ and thus oil-refining catalysts were more desirable than aluminium hydroxide as an aluminous raw material. The expansive cement samples showed somewhat lower flow value than that of OPC, but their compressive strengths were developed earlier and higher than that of OPC due to formation of ettringite in the early hydration time, which indicated the possibility of practical use of low-cost CSA clinker using industrial wastes only.

• 자원ㆍ환경경제연구
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• 제15권1호
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• pp.51-69
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• 2006

국내석유제품의 가격은 정부에 의해 최고가격 고시제에서 1997년 1월 국내 정유산업의 경쟁체제 도입을 위하여 유가자유화를 실시하였다. 이에 본 연구는 유가자유화 이후 국내정유산업의 경쟁도를 분석하였다. 분석방법은 구조적 모형인 Bresnahan (1982)과 Lau (1982)의 방법론(B-L 모형)과 비구조적 모형인 Panzar and Rosse (1987)의 방법론(P-R 모형)을 이용하였으며 분석 자료는 1994년 1월부터 2005년 6월까지 휘발유, 등유, 경유의 세전 소비자가격을 사용하여 유가자유화 이전과 이후를 나누어 비교하였다. 분석 결과, B-L 모형은 유가연동제 기간에 시장지배력이 존재하였으나 유가자유화의 도입으로 인해 균형가격이 감소하였음을 보였고, P-R 모형은 두 기간 모두 독점적 경쟁을 이루고 있음을 보였다. 그러나 두 모형에서 동일하게 유가자유화의 도입으로 인해 경쟁도가 증가하였음을 확인하였다.

• 한국염색가공학회지
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• 제18권6호
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• pp.31-36
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• 2006

Study has been made for producing anionic surfactant using waste fleshing scraps from the leather making process through refining, esterification, sulfonation and blending processes. As a most optimum lard oil refining method, refining was carried out for 4 hours under temperature of $120^{\circ}C$ and approximately 200 mbar vacuum, which gave a recovery of more than 80% lard oil. Refined lard oil obtained thus was undergone methlyl-esterification, then sulfonated to make a degreasing agent. By methyl-esterification using lard oil, more than 85% of fatty acid and $12{\sim}13%$ of glycerine were extracted from the oil. Sulfonation of the extracted fatty acid ester lard oil has shown most optimum at $15{\sim}20%$ chlorosulfonic acid content, and the content of bonding sulfate at this time was higher than 3.5%. Finally the followed anionic surfactant having degreasing force of 80% and higher could be made by blending process.