• Journal of the Optical Society of Korea
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• 제14권3호
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• pp.209-214
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• 2010

The Raman shift of water vapor is 3657 $cm^{-1}$, and this Raman signal can be easily separated from other Raman signals or elastic signals. However, it is difficult to make simultaneous Raman measurements on the three phases of water, namely, ice water, liquid water, and water vapor. This is because we must consider the overlap between their Raman spectra. Therefore, very few groups have attempted to make Raman simultaneous measurements even on two elements (water vapor and liquid water, or water vapor and ice water). We have made an effort to find three characteristic Raman wavelengths that correspond to the three phases of water after measuring full Raman spectra of water on particular days that are rainy, snowy or clear. Finally, we have found that the 401-nm, 404-nm, and 408-nm wavelengths are the most characteristic Raman wavelengths that are representative of the water phases when we are using the 355-nm laser wavelength for making measurements.

• Journal of Pharmaceutical Investigation
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• 제3권3호
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• pp.16-19
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• 1973

Stability is impaired in capsules in which there is a transfer of water vapor from capsule to the contents of the capsules. The water vapor transfer between AEA-coated capsules and corn starch, magnesium trisilicate in the closed container was examined. Experimental eguilibrium relative humidity after water vapor transfer and estimated values calculated from a formula of these substances were in close agreement with each other.

• 물과 미래
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• 제16권3호
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• pp.187-193
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• 1983

1972년부터 1981년까지의 고층자료를 이용하여 오산을 통과하는 대기수분량의 방향별, 계절별 수직분포를 계산하였다. 그 결과는 대기 수분의 통과량이 연 평균 총 1812g/cm·sec이었다. 계절별로는 여름에 그리고 방향별로는 서에서 동으로 통과하는 양이 가장 많았다. 또 겨울에는 수분 통과량의 최대치가 600mb∼800mb 층에서 나타났고, 여름에는 800mb∼900mb층이었다. 그리고 오산, 광주 및 포항의 고층자료로서 1979년의 1월과 7월의 두달 동안 수분이동의 발산량을 계산하여 간단히 논하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집E
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• pp.51-56
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• 2001

Vapor explosion is one of the most important problems encountered in severe accident management of nuclear power plants. In spite of many efforts, a lot of questions still remain for the fundamental understanding of vapor explosion phenomena. Therefore, KAERI launched a real material experiment called TROI using 20 kg of UO2 and ZrO2 to investigate the vapor explosion phenomena. In addition, a small-scale experiment with molten-tin/water system was performed to quantify the characteristics of vapor explosion and to understand the phenomenology of vapor explosion. A number of instruments were used to measure the physical change occurring during the vapor explosion. In this experiment, the vapor explosion generated by molten fuel water interaction is visualized using high speed camera and the pressure behavior accompanying the explosion is investigated.

• International Journal of Concrete Structures and Materials
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• 제3권1호
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• pp.15-23
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• 2009

Over about 30% of problems in construction is related to water-leaking, and the loss from this problem can incur as much as three times the cost of initial construction. Thus, water vapor pressure is known to be the primary cause of defective waterproofing. Accordingly, the theories on the relationship between water pressure and temperature as well as damp-proofing volume of concrete and the change in vapor pressure volume were reviewed and analyzed in this study by making test samples after spraying a dampness remover and applying waterproofing materials to the prepared test specimens. The result of measuring water vapor pressure with the surface temperature of the waterproofing (fluid-applied membrane) layer at the experimental temperature setting of about $10^{\circ}C$, which is the annual average temperature of Seoul, indicated that (1) the temperature of the fluid-applied membrane elevated to about $40^{\circ}C$, and the water vapor pressure generated from the fluid-applied membrane was about 0.03 N/mm 2 when the surface temperature of the waterproofing layer was raised to about $80^{\circ}C$. (2) when the temperature of the fluid-applied membrane of the waterproofing layer was raised from $30^{\circ}C$ to $35^{\circ}C$, water vapor pressure of about 0.01 N/mm 2 was generated, and (3) when a thermal source was applied to the fluid-applied membrane (waterproofing) layer, the temperature increased from $35^{\circ}C$ to $40^{\circ}C$, and approximately $0.005\;N/mm^2$ of water vapor pressure was generated.

• 한국산업융합학회 논문집
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• 제12권3호
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• pp.137-142
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• 2009

Burning velocity of methane-air mixtures with water vapor have been measured to study the process of flame propagation using schlieren photographs and computation. The computations were carried out for the burning velocity using premix code of Chemkin program to compare the experimental results. The quantity of water vapor contained were changed 5% and 10% of total mixtures, and equivalence ratio of mixtures between 0.8 and 1.2 were tested under the ambient temperature 323K and 373K. The results showed little difference between these two methods, the burning velocity was decreased by increasing the water vapor contents due to the interruption of flame development. And, the effect of ambient temperature was less significant by increasing the water contents on the burning velocity.

• 한국농림기상학회지
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• 제22권4호
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• pp.299-311
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• 2020

농산촌 지역 단일 집수역인 전남 구례군 간전면 중대리계곡과 경남 하동 악양면에서 각각 6지점과 14지점의 기상관측자료를 수집하여 복잡지형에서의 수증기압 및 상대습도 분포를 분석하였다. 중대리계곡에서는 2014년 12월 19일부터 2015년 11월 23일까지, 악양계곡에서는 2012년 8월 15일부터 2013년 8월 18일까지 가장 고밀도로 측정한 시기의 매시 기온과 습도(지면 위 1.5m)를 이용, 농업기상재해 조기경보시스템에서 사용되고 있는 기존의 수증기압 추정방식과 실제 수증기압을 비교하였다. 관측한 수증기압의 해발고도에 따른 기울기는 시간대(0300, 0600, … 2400 LST)에 따라 변동되었고, 야간일수록 위 아래의 수증기압차가 증대되었다. 지형·지표 조건이 다양한 악양계곡 관측 지점에서는 해발고도 외의 요인으로 인한 수증기압 변이가 지점별로 시간대에 따라 다르게 나타났다. 실제에 더 가까운 수증기압 및 상대습도 추정을 위해, 연구 대상지역의 관측자료로 해발고도 편차 당 수증기압 변화를 조정하는 계수를 도출하였다. 상대습도는 포화수증기압 대비 추정된 수증기압으로 모의하였으며, 조기경보시스템에서 사용된 기존 방법보다 도출된 계수를 활용한 추정방식에서 오차가 더 개선되었음을 확인하였다.

• 한국수자원학회논문집
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• 제37권2호
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• pp.109-119
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• 2004

이 논문에서 우리는 대기 대순환 모형을 사용하여 지구 온난화에 따를 육지 대기로의 물 수송 변화를 평가했다. 해양으로부터 육지로의 물 수송 변화량은 지구온난화에 따라 거의 연중 증가한다. 유라시아대륙의 물 수송량은 연중 170∼350${\times}$106 Mt/day 수준의 증가를 보인다. 아프리카로의 수송은 11월을 제외한 모든 달에 감소를 보이고 특히 8월과 9월에 -350${\times}$106 Mt/day의 최대 감소를 나타낸다. 유라시아와 아프리카를 제외한 다른 대륙들에의 수송은 $\pm$80${\times}$106 Mt/day 미만의 증가와 감소를 달에 따라 다르게, 그리고 불규칙하게 보인다. 지구온난화로 유라시아 대륙에로의 물 수송이 전체적으로 증가하지만, 이 대륙 안에 위치한 사막지역의 물 수송은 감소한다. 그러므로, 사막을 제외한 부분, 특히 몬순 지역에 증가 분이 집중될 것이고, 이러한 동아시아 몬순강화의 결과로 몬순지역에 상당한 가용수의 증가가 기대된다.

• 설비공학논문집
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• 제9권2호
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• pp.144-152
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• 1997

Film absorption involves simultaneous heat and mass transfer in the vapor-liquid system. In the present work, the absorption process of water vapor by an aqueous soluton of LiBr flowing inside of the vertical tube was investigated. The continuity, momentum, energy and diffusion equations for the solution film and vapor were formulated in integral forms and solved numerically. The model could predict the film thickness, the pressure gradient, and the heat and mass transfer rate. Particularly the effects of vapor flow conditions on the absorption process were investigated in terms of the vapor Reynolds number. As the vapor Reynolds number increased, the shear stress at the vapor-solution interface also increased. Consequently solution film became thinner at higher vapor flowrate under the co-currentflow condition. Thinner film was capable of higher heat transfer to the wall and leaded to higher absorption rate of the water vapor into the solution film.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2012년도 제42회 동계 정기 학술대회 초록집
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• pp.450-450
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• 2012

In recent days, advances in ZnO-based oxide semiconductor materials have accelerated the development of thin-film transistors (TFTs), which are the building blocks for active matrix flat-panel displays including liquid crystal displays (LCD) and organic light-emitting diodes (OLED). In particular, the development of high-mobility ZnO-based channel materials has been proven invaluable; thus, there have been many reports of high-performance TFTs with oxide semiconductor channels such as ZnO, InZnO (IZO), ZnSnO (ZTO), and InGaZnO (IGZO). The reliability of oxide TFTs can be improved by examining more stable oxide channel materials. In the present study, we investigated the effects of an ALD-deposited water vapor permeation barrier on the stability of ZnO and HfZnO (HZO) thin film transistors. The device without the water vapor barrier films showed a large turn-on voltage shift under negative bias temperature stress. On the other hand, the suitably protected device with the lowest water vapor transmission rate showed a dramatically improved device performance. As the value of the water vapor transmission rate of the barrier films was decreased, the turn-on voltage instability reduced. The results suggest that water vapor related traps are strongly related to the instability of ZnO and HfZnO TFTs and that a proper combination of water vapor permeation barriers plays an important role in suppressing the device instability.