• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2012년도 추계 학술논문 발표대회
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• pp.71-72
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• 2012

The purpose of this study is to evaluate the depth of carbonation considering the relative humidity in concrete using the FEM model. The difference of relative humidity in concrete has not been considered in calculating the carbonation depth in analytic model. That reason can make the over estimation in expectation of RC structure durability. The temperature and R.H. expectation model and the carbonation depth expectation model are development in past author's studies. The two models are coupled in this study. The fact that there is the difference between actual environment and acceleration test is revealed from FEM numerical analysis.

• Journal of Korean Society for Atmospheric Environment
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• 제24권E2호
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• pp.83-91
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• 2008

This work investigated the methodology to simultaneously optimize the ozone and relative humidity composition for the $NO_x$ degradation using soil biofilter. Experiments were made as a function of inlet ozone concentration ($0{\sim}1,770\;ppb$) and relative humidity ($38{\sim}81%$). Factorial design ($2^2+3$) and response surface methodology by central composite designs were used to examine the role of two factors and optimal response condition on $NO_x$ degradation. It was found that a second-order response surface model can properly interpret the experimental data with an $R^2$-value of 0.9730 and F-value of 71.83, based on which the maximum $NO_x$ degradation was predicted up to 92.8% within our experimental conditions.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.514-519
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• 2003

A computational study is performed to clarify the characteristics of supersonic moist air jet issuing from a simple sonic nozzle. The effects of the initial supersaturation on the Mach disk diameter and location, the barrel shock wave and jet boundary structures are investigated in details. The axisymmetric, compressible, Navier-Stokes equations, coupled with droplet growth equation, are solved using a third-order MUSCL type TVD finite-difference scheme. It is found that the Mach disk diameter increases with an increase in relative humidity of moist air. while its location is not significantly dependent on the relative humidity. As the relative humidity increases, the barrel shock wave and jet boundary are more expanded due to the local static pressure rise of nonequilibrium condensation.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.562-567
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• 2003

A computational study is performed to clarify the characteristics of supersonic moist air jet issuing from a simple sonic nozzle. The effects of the initial supersaturation on the Mach disk diameter and location, the barrel shock wave and jet boundary structures are investigated in details. The axisymmetric, compressible, Navier-Stokes equations, coupled with droplet growth equation, are solved using a third-order MUSCL type TVD finite-difference scheme. It is found that the Mach disk diameter increases with an increase in relative humidity of moist air. while its location is not significantly dependent on the relative humidity. As the relative humidity increases, the barrel shock wave and jet boundary are more expanded due to the local static pressure rise of nonequilibrium condensation.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 1996년도 International Conference on Agricultural Machinery Engineering Proceedings
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• pp.1126-1135
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• 1996

This study was conducted to select the sensors for measuring temperature, relative humidity, and air velocity among the major environmental factors affecting the pig productivity as a part of the study for the optimum production system model development of pig-housing. The study results are summarized as the follows : Two sensors , HMP233L and HANI, were tested for measuring temperature and relative humidity , Test results were analyzed by the statistical methods. And the sensor, HMP233L was selected as a proper sensor for temperature sand relative humidity measurement . An air velocity sensor was tested. Test results showed that its accuracy was low and incongruent for the air velocity measurement when it was lower than 4m/s.

• International Journal of Industrial Entomology and Biomaterials
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• 제5권1호
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• pp.53-57
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• 2002

The growth and multiplication of Aspergillus flavus Link and A. tamarii Kita were observed in vitro under variable temperatures of $22-31^{\circ}C$. The matte weight of mycelium and number of conidia/ml were significantly higher (P < 0.01) at the higher temperature than the lower temperature in both the species of Aspergillus. In vivo the mortality in silkworm, Bombyx mori L. with the infection of Aspergillus species was significantly (P < 0.01) different at different temperature and relative humidity conditions.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2006년도 춘계학술논문 발표대회 제6권1호
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• pp.97-100
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• 2006

This paper report the result of the investigation on the properties of drying shrinkage for alkali-activated slag mortar in different relative humidity Commonly we know that drying shrinkage means lost more moisture but the mechanism of drying shrinkage of alkali activated slag mortar is not entirely due to the quantity of weight loss of water from mortar. pore size distribution and the calcium silicate hydrate gel characteristics have a critical influence on the magnitude of drying shringkage to alkali activated slag mortar. For this investigation, Ca(OH)2, Na2SiO4 were as alkali activator with 5 dosages(6%, 9%, 12%, 15%, 20%) and curing condition were three different relative humidity(35%, 65%, 95%) at $20{\pm}3^{\circ}C$

• 한국세라믹학회지
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• 제24권2호
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• pp.101-110
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• 1987

The relative electrical conductivity of vacuum deposited Al films on a soda-lime(2947) and an alumino boro silicate(7809) glass was investigated with the variation of the relative humidity,temperature and film thickness. The structure and microstructure of Al films before and after exposure to the humidity wereexamined by the X-ray Diffractormenter(XRD) and Scanning Electron Microscope(SEM). As the relative humidity increased, the electrical conductivity of Al films on both glasses was decreased. However, the Al films on 7809 glass showed higher conductivity than that of 2947 glass under the same testing conditions. The decreasing of electrical conductivity was caused by the formation of Aluminum hydroxide which was made by the reaction between the aluminum films and water vapor.

• Journal of Applied Biological Chemistry
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• 제43권4호
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• pp.250-253
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• 2000

The effects of high relative humidity (RH) on the physicochemical properties and microbial activity of mature green tomatoes ('Dombito') during refrigerated storage were determined at three temperatures (5, 10, and $15^{\circ}C$) and four different RH levels (91, 94, 97, and 99%). At each temperature, the weight loss rates of tomatoes at different levels of RH were significantly (p<0.05) different from each other. For the samples stored at $10^{\circ}C$, the weight losses were generally higher than those for the samples at $15^{\circ}C$ within the same RH level (i.e., greater vapor pressure deficit). The color change rates ('a' value) showed positive slopes, indicating that the tomato color was changing from green to red. Neither bacteria nor fungi caused visible damages to the samples, and the microbial counts were below 650 colony forming units/$cm^2$ during the test period.

• Journal of Applied Biological Chemistry
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• 제43권3호
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• pp.161-164
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• 2000

The effects of storage temperature and high relative humidity (RH) on the weight loss, color change, and microbial activity of a mushroom ('Sylvan' hybrid white) were investigated. The experiment was performed at three temperature (5, 10 and $15^{\circ}C$) and four different relative humidity levels (91, 94, 97 and 99%). The weight loss of the tested samples had a highly correlated linear relationship with storage time at each RH level during storage. Both the storage temperature and RH levels in the experiment had signigicant effects (p<0.05) on the weight-loss rate of the tested samples. The loss whiteness of mushrooms was not significantly affected (p>0.05) by RH ranges at the same temperature. No visible damage was caused by either bacteria or fungi in all samples during storage.