• 한국분무공학회지
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• 제20권1호
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• pp.7-13
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• 2015

In this study, the behavior of water or nanofluid droplets impacting upon a hot surface was investigated by visualization of impacting phenomena with time-delayed photographic technique. Changing the mass ratio of nanofluid and the temperature of the heated surface, the characteristics of the spreading behavior and the diameter of spreading liquid film was compared between water and nanofluid droplets. The impacting droplet spreaded as a liquid film after impact and nanofluid droplets spreaded more widely than water droplets. After reaching the maximum diameter, water droplets shrinked more than nanofluid droplets. Based on this, the heat transfer area from a hot surface to impacting nanofluid droplets would be wider than that of impacting water droplets. Considering individual impacting droplet only, spray cooling using nanofluid would be better than using water.

• 대한수의학회지
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• 제35권1호
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• pp.39-44
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• 1995

도롱뇽(Hynobius leechii)의 위장관 내분비세포를 면역조직화학적으로 관찰하였던 바, BPP 면역반응세포는 유문부에서 중등도, 십이지장과 소장에서 소수로 관찰되었다. 중등도의 somatostatin 면역반응세포는 유문부에 국한되어 출현하였다. 5-HT 면역반응세포는 전장관에 걸쳐 출현하였으나 유문부에서 다수 그리고 직장에서 극소수로 분포하였다. 특히 BPP와 5-HT면역반응세포는 도롱뇽에서 최초로 동정하였다.

• 진공이야기
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• 제2권1호
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• pp.17-20
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• 2015

In this article, a historical and scientific review on the development of an ultrafast electron microscope is supplied, and the challenges in further improvement of time resolution under sub-picosecond or even sub-femtosecond scale is reviewed. By combining conventional scanning electron microscope and femtosecond laser technique, an ultrafast electron microscope was invented. To overcome its temporal resolution limit which originates from chromatic aberration and Coulomb repulsion between individual electrons, a generation of electron pulse via strong-field photoemission has been investigated thoroughly. Recent studies reveal that the field enhancement and field accumulation associated with the near-field formation at sharply etched metal nanoprobe enabled such field emission by ordinary femtosecond laser irradiation. Moreover, a considerable acceleration reaching 20 eV with near-infrared laser and up to 300 eV acceleration with mid-infrared laser was observed, and the possibility to control the amount of acceleration by varying the incident laser pulse intensity and wavelength. Such findings are noteworthy because of the possibility of realizing a sub-femtosecond, few nanometer imaging of nanostructured sample.in silicon as thermoelectric materials.

• 한국의류학회지
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• 제28권9_10호
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• pp.1292-1299
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• 2004

This survey was carried out on 256 smallholder farmers of the Jeonbuk Province to analyze their current behavior in pesticide usage and the use of protective clothing during spray work. The interviewees were at the age of about 50's in both males and females: they performed spray work mainly for their own farms. Many of them were not very well aware of the danger of pesticides and the adequate methods of pesticide handling. Water drinking and smoking during break time were the endangering factors of pesticide intoxication, reaching to 30-60% sprayers. Most of sprayers had experienced the exposures to pesticides during spray work and appealed some subjective clinical symptoms to the exposure, but they seldom sought medical treatments. More than 70% of respondents had not been wearing protective equipments during spray work. The results will be used as basic information in designing the improved protective clothing more acceptable by pesticide sprayers.

• 한국문헌정보학회지
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• 제45권2호
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• pp.5-21
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• 2011

There is an explosion of talk about crucial, new literacies for the 21st Century, for example critical thinking, problem-solving, media literacy, technology literacy, digital literacy, visual literacy. The other day, there was even an article about "gaming literacy!" How does one make sense of it all? The common factor in all these literacies is "information" - information seeking, information use, information processing, information presentation, and information evaluation. And, these "information" elements come together in information literacy: the ability to engage in effective and efficient information problem-solving. Information literacy is the overarching and unifying literacy, and all libraries have a unique and essential role to play in delivering meaningful information literacy programs to people of all ages. In this keynote paper and address, Professor and Dean Emeritus Mike Eisenberg will define the concept and structure of library-based information literacy programs and offer strategies for developing and implementing information literacy programs that are comprehensive(reaching all users), predictable (consistent over time), and accountable(measured and reported).

• 한국패류학회지
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• 제29권1호
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• pp.43-50
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• 2013

We investigated the growth performance of oysters (initial shell height $57.5{\pm}8.5$ mm) under differing conditions of tidal exposure time and culture rack height in an experiment that commenced in April, 2011. Significant differences were observed in shell height from June 2011, in total weight from August, and in meat weight from September. Fatness tended to decrease during the experimental period, but was not significantly different at the end of the experiment. Significant differences in survival rates were mainly observed from June to August. After September, further changes were not observed in any experimental treatment group. The greatest growth potential ($L_{\infty}$) and survival rate were observed at a sea level of approximately 116 cm. The results indicate that in the study area the use of oyster culture conditions involving 1 or 2 h of tidal exposure and 60 - 70 cm rack height could result in oysters reaching the favored commercial half shell size within 14 months, with > 80% survival.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 하계학술발표대회 논문집
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• pp.468-473
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• 2008

Currently, most of the buildings have been the high-rise buildings and not only the damage for people but also loose of property have been increased significantly. Furthermore, the damage for residents in indoor is increased significantly, the law related to fire protection is not established yet. We discussed safety of evacuation according to unitary system in standard apartment. At a result, when installing the smoke ventilation system, the RSET has been achieved and delay effect for reaching time of CO and smoke area has been obtained.

• Journal of Magnetics
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• 제6권4호
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• pp.126-128
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• 2001

The effect of rapid thermal anneal (RTA) has been investigated on the properties of an FeMn exchange-biased magnetic tunnel junction (MTJ) using magnetoresistance and I-V measurements and transmission electron microscopy (TEM). The tunneling magnetoresistance (TMR) in an as-grown MTJ is found to be ∼27%, while the TMR in MTJs annealed by RTA increases with annealing temperature up to 300$\^{C}$, reaching ∼46%. A TEM image reveals a structural change in the interface of A1$_2$O$_3$layer for the MTJ annealed by RTA at 300$\^{C}$. The oxide barrier parameters are found to vary abruptly with annealing time within a few ten seconds. Our results demonstrate that the present RTA enhances the magnetoresistive properties of MTJs.

• 한국연초학회지
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• 제19권1호
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• pp.70-75
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• 1997

The expansive properties of leaf tobacco by nitrogen gas was investigated with cut tobacco AB3O-1, CD3L-1(NC82). Major factors for the best expansion of the tobacco by the gas were an impregnated pressure and expansion temperature. The expansion rate for AB3O-1 and CD3L-1 at 250℃, 750kg/cm2 was 96.6%, 99.4% respectively. The shred size and fineness index at 96.6% of expansion rate for AB3O-1 was almost the same as at 58.3% for CD3L-1. The time reaching at equilibrium moisture under of RH 57% was 36hr in non-treated leaf tobacco, but it was 20hr in expanded tobacco. We confirmed that total sugar contents of leaf tobacco by the expansion was decreased with 9.3∼10.9%. Total alkaloid was decreased with 17.5∼21.1% and ether extracts was declined with 4.9∼9.3%. These results suggest that the expansion method of leaf tobacco by nitrogen gas is a useful method without any serious environmental troubles. Key words : expansion, nitrogen gas, heat treatment, tobacco.

• 한국식생활문화학회지
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• 제9권4호
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• pp.329-333
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• 1994

발효시간을 $0{\sim}10$시간으로 달리한 증편 반죽에서 발효시간에 따른 이화학적 성질 변화를 검토하였다. 발효경과에 따라 pH는 감소하였으나 적정산도와 젖산은 계속적으로 증가하였다. 발효 중 총당은 계속적으로 감소하였으나 환원당은 발효초기 크게 증가하여 발효 4시간에 건물 기준으로 최대 101 mg/g에까지 도달한 다음 다시 감소하였다.