• 한국제4기학회지
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• 제24권2호
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• pp.1-11
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• 2010

지표 특성 차이에 따라 외부강제력에 대한 차별적인 반응을 보이는 지표 평형온도 분포를 실험하기 위해 에너지 균형 모형(Energy Balance Model, EBM)이 사용되었다. EBM은 입사되는 복사에너지가 각 위도별로 수송되는 에너지와 방출되는 복사에너지의 합과 균형을 이루었을 때의 온도를 산출한다. 지구의 에너지 원천인 태양복사에너지를 전지구 에너지 균형에 있어 중요하게 취급하기 위하여 위도별 알베도 변화뿐만 아니라 해륙의 분포 차이에 따른 에너지 균형을 고려한 지구 평형온도 분포에 관한 실험이 수행되었으며, 입사되는 태양복사에너지량을 강제력으로 하여 위도별 알베도의 선형적인 증감, 극지역 알베도의 5%, 10%, 15% 증감에 대한 반응, 극과 중위도 지역에서의 상반된 증감에 대한 반응을 실험하였다. 그리고 얼음-알베도 피드백의 유무에 대한 실험도 수행되었다. 극지역의 알베도를 증가시키면 입사되는 태양에너지를 차단시켜 위도별 열수송을 감소시키는데 이는 극지역을 저에너지 상태로 유지시킴으로써 저위도에서부터의 에너지 수송을 강화시킨다. 이러한 수송량의 차이로 인해 중위도 지역의 온도 변화는 극지역에 비해 크게 나타난다. 육지는 해양에 비해 열용량이 작기 때문에 평형온도에 도달하는 시간이 짧으며 알베도에 따른 온도변화에 민감하여 해양과의 온도차이를 유발시킨다. 따라서 평형온도는 지표가 가지는 특성인 알베도와 열용량의 차이에 따라 다르게 나타나며 알베도가 증가함에 따라 감소하고 열용량이 작을수록 변화율이 큰 특징이 있다. 얼음-알베도 피드백은 알베도의 선형적인 증가에 따른 지구 평형온도의 감소를 가속화시키지만 국지적으로는 비선형적인 감소를 보인다.

• 한국전산유체공학회:학술대회논문집
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• 한국전산유체공학회 1996년도 춘계 학술대회논문집
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• pp.40-45
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• 1996

This paper discribes the viscous interaction of Hypersonic Wedge Flows using Roe FDS and AUSM+. For this purpose we developed the frozen and the equilibrium code and numerically simulated the viscous interaction by changing the surface temperature and the mach number. We used curve fitting data in NASA Reference Publication 1181, 1260 to calculate equilibrium properties. We compare the equilibrium flow with the frozen flow. We conclude that the mach number and the surface temperature are significant parameters, as the surface temperature and the mach number increase the viscous interaction becomes stronger, and we must consider high-temperature effects in hypersonic flow

• 대한자원환경지질학회:학술대회논문집
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• 대한자원환경지질학회 2002년도 춘계 공동학술발표회
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• pp.458-462
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• 2002

• 대기
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• 제20권4호
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• pp.427-436
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• 2010

The single-scattering optical properties of ice crystals in cirrus clouds by the aircraft measurement data were investigated, and the radiative equilibrium temperatures and radiative fluxes were calculated and analyzed by radiative convective model with the variations of ice crystal habits and sizes in cirrus clouds. The homogeneous cloud is assumed to be in the layer 200~260 hPa with an ice crystal content of $10gm^{-2}$ for the flux calculation. The profiles of temperature, humidity, and ozone typical of mid-latitude summer are used. The surface albedo is assumed to be 0.2 for all spectral bands and the cosine of solar zenith angles is 0.5. The result of radiative equilibrium temperature at surface was less than surface temperature of the standard atmosphere data in case of smaller effective ice crystal size and larger optical thickness. The column, aggregation and plate in 6 ice crystal habits were the most effective in positive greenhouse effect and bullet-4 was the worst in it. At the surface, the maximum difference of equilibrium temperature by 6 kinds of ice crystal habits were about 3~15 K with 30 sample aircraft measurement data.

• 대한기계학회논문집B
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• 제26권10호
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• pp.1427-1435
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• 2002

The main aim of the present article is numerically to investigate the micro-scale heat transfer phenomena in a silicon microstructure irradiated by picosecond-to-femtosecond ultra-short laser pulses. Carrier-lattice non-equilibrium phenomena are simulated with a self-consistent numerical model based on Boltzmann transport theory to obtain the spatial and temporal evolutions of the lattice temperature, the carrier number density and its temperature. Especially, an equilibration time, after which carrier and lattice are in equilibrium, is newly introduced to quantify the time duration of non-equilibrium state. Significant increase in carrier temperature is observed for a few picosecond pulse laser, while the lattice temperature rise is relatively small with decreasing laser pulse width. It is also found that the laser fluence significantly affects the N 3 decaying rate of Auger recombination, the carrier temperature exhibits two peaks as a function of time due to Auger heating as well as direct laser heating of the carriers, and finally both laser fluence and pulse width play an important role in controlling the duration time of non-equilibrium between carrier and lattice.

• 한국연소학회지
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• 제1권1호
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• pp.31-39
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• 1996

An equilibrium analysis was carried out to determine principal species in the incineration of hazardous waste, which was assumed as a compound of hydrocarbon fuel, chlorine, sulfur, and heavy metals, and their behaviors with variation of temperature, chlorine and sulfur concentrations. Calculated results showed that the most important parameter influencing the principal species was temperature. Chlorine concentration affected on mole fractions of the species, especially at high temperature. Existence of sulfur had a significant effect on the species at low temperature, regardless of surfur concentration. Generally, principal species at high temperature were chlorides and oxides, while the principal species at low temperature were sulfides. As temperature increased, mole fractions of the principal species increased at low temperature, however, mole fractions of some metal species decreased at high temperature.

• 천문학회보
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• 제44권1호
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• pp.53.1-53.1
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• 2019

We apply a non-equilibrium ionization (NEI) model to a supra-arcade plasma sheet, shocked plasma, and current sheet. The model assumes that the plasma is initially in ionization equilibrium at low temperature, and it is heated rapidly by a shock or magnetic reconnection. The model presents the temperature and characteristic timescale responses of the Atmospheric Imaging Assembly (AIA) on board Solar Dynamic Observatory and X-ray Telescope (XRT) on board Hinode. We compare the model ratios of the responses between different passbands with the observed ratios of a supra-arcade plasma sheet on 2012 January 27. We find that most of observations are able to be described by using a combination of temperatures in equilibrium and the plasma closer to the arcade may be close to equilibrium ionization. We also utilize the set of responses to estimate the temperature and density for shocked plasma associated with a coronal mass ejection on 2010 June 13. The temperature, density, and the line of sight depth ranges we obtain are in reasonable agreement with previous works. However, a detailed model of the spherical shock is needed to fit the observations. We also compare the model ratios with the observations of a current sheet feature on 2017 September 10. The long extended current sheet above the solar limb makes it easy to analyze the sheet without background corona. We find that the sheet feature is far from equilibrium ionization while the background plasma is close to equilibrium. We discuss our results with the previous studies assuming equilibrium ionization.

• 한국연초학회지
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• 제26권1호
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• pp.43-49
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• 2004

This study was carried out to investigate moisture sorption and desorption characteristics followed by tobacco type. Experiments were performed at various temperature(5, 15, 25, 40 $^{\circ}C$) and relative humidity range (11～84 %) controlled by saturated salt solution. Regression equation was obtained to predict equilibrium moisture according to various relative humidity, temperature and tobacco types. The obtained regression equation showed high $R^2$(above 0.95) and predicted accurate equilibrium moisture. Equilibrium moisture contents declines in the following order when a relative humidity is 50 % or above: expanded stem, flue-cured, expanded tobacco, reconstituted tobacco, USA flue-cured, orient, burley. To maintain 13 % moisture of each tobacco type in the range of 5～40 $^{\circ}C$ it is recommendable to control relative humidity 49～56 % for expanded stem, 50～57 % for flue-cured, 54～61 % for USA flue-cured, 56～60 % for reconstituted tobacco, 57～62 % for expanded tobacco, 58～64 % for orient and 58～65 % for burley, respectively. It means that the relative humidity of each tobacco type should be differently controlled to maintain the same moisture under the same temperature. In the range of 5～25 $^{\circ}C$, the lower temperature showed the higher equilibrium moisture content.

• 대한기계학회논문집
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• 제19권12호
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• pp.3372-3381
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• 1995

An equilibrium analysis was carried out to determine principal species of heavy metals in waste incineration and their behaviors with variation of temperature, chlorine concentration, excess air ratio, and C/H ratio. The waste was assumed as a compound of hydrocarbon fuel, chlorine, and metals. Calculated results showed that the most important parameter to determine the principal species was temperature. Chlorine concentration also affected on mole fractions of the principal species. Generally principal species at high temperature were chlorides while there were some metals of which principal species were oxides. At low temperature mole fractions of the principal species increased, but at high temperature mole fractions of some metal species decreased. C/H ratio of the hydrocarbon fuel and excess air ratio had little effect on mole fractions of the metal species, compared to the temperature and chlorine concentration.

• 한국환경과학회지
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• 제8권3호
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• pp.371-377
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• 1999

The effects of benzamidoxime concentration, solvents and temperature on the degree of metal extraction were investigated to apply benzamidoxime to heavy metal extraction as chelating agent. Benzamidoxime was synthesized from benzonitrile with hydroxylamine. The chemical structure of benzamidoxime was identified. The degree of heavy metal extraction was increased with increasing the concentration of benzamidoxime and decreasing the extraction temperature. Benzamidoxime was found to be an concentration of benzamidoxime and decreasing the extraction temperature. Benzamidoxime was found to be an effective extractant for Cu-extraction by benzene or chloroform. The relationship between the thermodynamic overall equilibrium constant and absolute temperature was expressed as log K = -5.56 ＋ $855T^{-1}$. Heat of extraction, $$\Delta$H^0$ were calculated from overall equilibrium constants at various temperature and the extraction reactionby benzamidoxime was found to be exthothermic.