• Nuclear Engineering and Technology
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• 제8권3호
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• pp.159-168
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• 1976

Ceric 염과 ${\gamma}$-선을 계기로 하여 Nylon 직포에 Acrylic acid를 접목반응 시켰다. 접목반응된 Polyacrylic acid의 분자량 분포를 측정한 결과 양 평균분자량과 수 평균분자량의 비는 낮은온도(-184$^{\circ}C$)dptj 보다는 상온에서 더 높았다는 것을 알았다. Polyacrylic acid의 양 평규 sqnswkfid은 Sodium hydroxide용액에서 점도를 측정하여 계산하였다. Nylon에 Acrylic acid가 중합반응될 때에 중합반응에 영향을 주는 요소들을 시험하였다. Nylon의 산화반응은 질소원자에 인접해 있는 methlene group에서 일어나 free-radical이 만들어 진다는 메카니즘을 논의 하였다.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 2004년도 하계종합학술대회 논문집(2)
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• pp.363-366
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• 2004

PZT thin films were formed by rf-magnetron sputtering on $Pt/Ti/SiO_2/Si$ substrate. Bulk PZT target containing $5\%$ excess PbO was used. They were formed with in-situ process at $650^{\circ}C$ as total thickness of 175 and 250 nm after the depositing of thin PZT films at room temperature, i. e. 2-step Sputtering. It was found that the ferroelectric perovskite phase is formed at $650^{\circ}C$ by XRD and the interface between room temp.-layer and $650^{\circ}C$ -layer is not existent. In the samples undergoing 2-step sputtering the dielectric constant was 600 or more and the leakage current density was $2{\times}10^{-7}A/cm^2$. So, we found that the room temp.-layer on the bottom electrode stabilize the underlaid layers.

• 한국잠사곤충학회지
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• 제40권1호
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• pp.70-77
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• 1998

This study was carried out in order to find out the relationship between physical and chemical properties of silk fiber treated by concentrated calcium nitrate solution. The tensile, thermal and dynamic mechanical properties are also examined on Ca(NO3)2 treated silk fibers. The tensile properties of silk fibers treated by calcium nitrate changed with a concentration. The thermal behavior were also affected by the concentration of calcium nitrate. The degradation temperature (endotherms) and glass transition temperature shifted to lower temperature as the treated concentration increased. It is thought that the physical properties are strongly related to the structure and morphology of Ca(NO3)2 treated silk fibers. As a result, these give property changes with a concentration dependence.

• 한국전자파학회:학술대회논문집
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• 한국전자파학회 2000년도 종합학술발표회 논문집 Vol.10 No.1
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• pp.302-305
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• 2000

최근에 ITU-R에서 30～3,000MHz 주파수 범위에서 사용할 수 있는 포괄적인 전계 강도 커브를 제시하고 있다. ITU-R Question 중의 하나인 의제 210/3에서 요구하는 내용은 '30MHz～3GHz 대역의 육상이동과 지상방송 업무를 위한 전파전파 예측절차'이다. 이러한 의제를 WP SG3에서 연구하여 부속서 3K/TEMP/4에 정리하였다. 본 논문에서는 위 부속서 3K/TEMP/4에 나와있는 전송손실 예측 그래프의 적용범위와 적용환경을 알아보기 위해 일반적인 실험적 경로손실 예측식인 Okumura-Hata 모델 그리고 Cost231-Hata 모델과 비교 분석하였다.

• 한국물환경학회지
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• 제22권6호
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• pp.1075-1081
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• 2006

In this research, mortality rates of pathogen indicator microorganisms discharged from various point sources and diffuse sources in urban area were measured. Water samples were taken at domestic sewer, combined sewer overflow, effluent from a wastewater treatment plant, urban river, and sediment of an urban river. Mortality rates of indicator microorganisms in domestic sewer estimated by assuming the first order kinetics at $20^{\circ}C$ were as follows: total coliform = 0.092/day, fecal coliform = 0.185/day, E. coli = 0.252/day, and fecal streptococci = 0.281/day. Sensitivity of mortality rates of total coliform on temperature was estimated as $K_{temp}=K_{20}{\times}1.162^{(temp-20)}$ for the range of $10-20^{\circ}C$. Mortality rates due to sunlight were measured as 1.22-1.59/day while mortality rate due to settling for 40 min were estimated as $9.21{\times}10^3-20.0{\times}10^3/day$.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 영호남 합동 학술대회 및 춘계학술대회 논문집 센서 박막 기술교육
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• pp.133-135
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• 2006

SBN60 and SBN60/30 thin films were deposited by ion beam sputtering technique. Using the ceramic target of the same composition and Pt(100)/$TiO_2$/$SiO_2$/Si or Pt(111)/Ti/$SiO_2$/Si substrate, crystallization and orientation behavior as well as electric properties of the films were examined, Thickness was controlled to $3000{\AA}$ and the films were heat-treated at $650^{\circ}C{\sim}800^{\circ}C$. The orientation and crystallization behavior were observed which showed the dependence on processing condition($O_2$/Ar ratio, substrate temp, annealing temp...).

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 추계 학술발표회
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• pp.1218-1231
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• 2008

Recently the energy dependence of LNG resource is being increased. So the enlargement of LNG storage is constructed in the coastal area. Most of LNG tanks are constructed below the ground level, and thus the hydraulic uplift pressure could be a problem against the weight of tank structure. Specifically, the settlement of foundation soil in the LNG tank is also important in the aspect of safety. The low temperature around LNG tank is induced the ground freezing and hence increasing the soil volume and earth pressure. The additional lateral earth pressure due to ground freezing could be applied to the LNG tank. In this study, the stability of LNG storage tank was evaluated with consideration of freezing earth pressure by using computer program TEMP-W.

• 한국수소및신에너지학회논문집
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• 제16권4호
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• pp.386-390
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• 2005

Al film(135.5 nm thick) with Pd film(39.6 nm thick) on the top of it was made by thermal evaporation method. Electrical resistance change due to hydrogen absorption and desorption was measured by four point measurement method. The sample was activated by hydrogen absorption and desorption cycling at room temp. Hydrogen was introduced into the film by increasing hydrogen gas pressure step by step up to 640 torr at room temp. The resistance change ratio was decreased to 12 % with increasing hydrogen pressure in contrast to normal metal behavior. This strange tendency was not understood yet. Further study is needed to find out the mechanism of hydrogen absorption in Al in Al/Pd film.

• 한국수소및신에너지학회논문집
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• 제25권1호
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• pp.72-78
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• 2014

The study has been designed to develop water vapor supply for semiconductor industry, industrial gas manufacturing, impurities analysis, and fuel cell. Water concentration in air reached $1019{\mu}mol/mol$ at dew temp ($-20^{\circ}C$) and water concentration in CO2 reached $127{\mu}mol/mol$ at dew temp ($-40^{\circ}C$. Carbon dioxide needs more wet gas than air because interaction potential of carbon dioxide shows more strong attraction than air.

• 한국농촌생활과학회지
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• 제6권1호
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• pp.25-30
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• 1995

This study was designed to obtain the basic data developing the UV ray protective garments for the plastichouse workers. Two subjects were volunteered for 1hr. wear test in plastic house, and the ensembles was composed of one of three kinds blouse (UV blocking blouse, polyester/cotton 47/53 blouse, and polyester blouse), shorts, sleeveless undershirts, pants and socks. The measurements were rectal temperature, skin temperature, microclimate inside clothing, subjective sensation, and the colour difference of UV sensor. The results were as follows: 1. Microclimate especially, temperature inside clothing of polyester blouse was the highest among the garments. And UV-proof polyester blouse showed the lower mean skin temperature and microclimate than others. Showing the highest sweat volume. 2. No significant difference on UV ray blocking function among 3 kinds of garment was shown. 3. We could conform that in spring for the plastic house wぉw s garment low thermal insulating value and wide covering area were more important factors than UV blocking function of fabric.