• Journal of Biosystems Engineering
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• v.23 no.5
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• pp.465-472
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• 1998

In this study short gain rough rice(Chu-cheong) with initial moisture content of around 12%(w.b.) was exposed to 3 levels of relative humidity(70, 80 and 90%) and 3 levels of temperature(20, 25 and 3$0^{\circ}C$) of the air, in order to evaluate the adsorption characteristics of rough rice and the rate of cracked kernels which will serve as the basic data when developing the quality adjusting equipment. The result showed that the moisture content of rough rice increased rapidly during the early stages of moisture adsorption like other grains, and at least 70% of the adsorption occurred within the first 24 hours of exposure to the humid environment. Adsorption rate was more related to relative humidity than the temperature of air stream, and the higher the relative humidity, the higher the adsorption rate. And the Page's equation predicted best the adsorption process of this study. Experimental results for the crack generation during the adsorption process showed that the higher the relative humidity the more the cracked kernels, and that the temperature had little effect. An empirical equation was developed to predict the crack ratio for the conditions of this study, and Nishiyama model predicted better the crack generation than Hoerl model.

• Korean Journal of Environmental Biology
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• v.22 no.2
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• pp.279-286
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• 2004

This study observed the temperature and humidity within the green zone to understand the effect that land coverage and the structure of forests have on the relief of micro-climate control. Based on this set of data, this study interpreted, through the regression analysis, the relevance of land coverage of the green zone with temperature and distribution of humidity, as well as the amount of green with the relief of microclimate control. The results of the study demonstrated that high temperature regions were formed in barren areas, and low temperature regions in forests or near the water. In particular, low temperature was found in areas covered with tall and small trees, the water surrounded by forests and areas enclosing small rivers. Furthermore, mechanisms causing low temperature were, among others, the ratio of land coverage (forest, grassland, water). In fact, the temperature reduction effect varied in accordance with the types and ratios of the land coverage. Humidity also showed a close correlation with the distribution of temperature high temperature areas had low humidity and low temperature areas had high humidity. Such a phenomenon.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 1998.10a
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• pp.217-223
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• 1998

This study was performed to figure out water consumption of the twisted sweet pepper in a greenhouse. Obtained results are as follows; 1. The ambient temperature was nearly same as the normal year, while the average air temperature and the relative humidity in the green house were little bit higher than those of the outside condition. The transparency of the greenhouse roof was approximately 50%. The total amount of rainfall during the irrigation period was 1,040㎜ which is 350㎜ higher than 1997 during the same period. 2. In case of pot cultivation, as the saturation ratio was increased, the aeaf area and plant height and yield were also increased. The yield from the field cultivation was higher than the average yield from the pot cultivations which are treated by three levels of saturation ratio. 3. The variation of daily consumptive use of the twisted sweet pepper was very large in it's range. In case of the pot cultivation, as the saturation was increased, the daily and the total consumptive use were increased. 4. The daily consumptive use was strongly correlated with the ambient temperature, while it was weakly correlated with the relative humidity and solar radiation. 5. There were close correlation between plant environment; leaf area, plant height and yield, and consumptive use. As the saturation ratio was increased, the correlation between those plant factors and consumptive use was getting stronger.

• Magazine of the Korean Society of Agricultural Engineers
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• v.42 no.4
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• pp.59-66
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• 2000

This study was carried out to investigated the water requirement of twisted sweet peppers which are cultivated in a green house. The meteorological conditions during the experiment period was close to that of normal year except the temperature and relative humidity. The growth status was improved with the increased saturation ratio. The range of the variation of daily water requirement were very large. The peak consumption occurred in the early August. And the higher saturation ratio resulted in higher water requirement. The total water requirement were about 57.180g/d/plant for pot with 100% (P100) of saturation , about 38.700g/d/plant for pot with 80%(P80) of saturation , about 23,720g/d/plant for pot with 60%(P60) of saturation, and about 53, 390g/d/plant for field cultivation in the green house, respectively. The water requirement was correlated with average ambient temperature and growing status, while no significant correlation were found between water requirement and minimum relative humidity or intensity of solar radiation. And the higher correlation was shown as the saturation ratio was increased. The transpiration coefficients of twisted sweet pepper were 378.0g/g for field cultivation in the green house, 363.3g/g for P100, 338.7g for P80 which was the smallest among pot cultivation , and 472.1g/g for P60 , respectively.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.3
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• pp.19-31
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• 2007

Humidity and strain were estimated for understanding the relation between humidity change by self-desiccation and shrinkage in high-performance concrete with low water binder ratio and containing fly ash and blast furnace slag. Internal humidity change and shrinkage strain were about 10%, 10%, 7%, 11%, 11% and $320{\times}10^{-6}$, $270{\times}10^{-6}$, $231{\times}10^{-6}$, $371{\times}10^{-6}$, $350{\times}10^{-6}$ respectively on OPC30, O30F10, O30F20, O30G40, O30G50 and from the results, fly ash made humidity change and strain decrease but slag increase comparing with ordinary portland cement. Considering only relation internal humidity and shrinkage by self-desiccation, humidity change and shrinkage represented the strong linear relation regardless of mineral admixture. For specifying the relation on internal humidity change and autogenous shrinkage strain, shrinkage model was established which is driven by capillary pressure in pore water and surface energy in hydrates on the assumption of a single network and extended meniscus in pore system of concrete. This model and experimental results had a similar tendency so it would be concluded that the internal humidity change by self-desiccation in HPC originated in small pores less than 20nm, therefore controlling plan on autogenous shrinkage might be focused on surface tension of water and degree of saturation in small pore.

• Food Science and Preservation
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• v.9 no.2
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• pp.126-130
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• 2002

Optimal storage conditions were investigated for 'Fuyu' persimmon fruits and cucumbers were stored under conditions of 70% relative humidity(RH) at 25$^{\circ}C$, 80% RH at l0$^{\circ}C$ and 90% at 5$^{\circ}C$ or l0$^{\circ}C$ of relative humidity, respectively and their qualities in microbial counts, decay ratio, surface color difference and chemical attributes were monitored during the storage period. 'Fuyu'persimmon fruits and cucumbers stored under 90% of relative humidity showed the minimal change in weight loss, decrease of ascorbic acid content, surface color difference and decay by putrefactive microorganisms. As the results of this experiment, 'Fuyu' persimmon fruits and cucumberf stored under 9% of relative humidity were best fer maintaining their freshness.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.767-770
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• 1999

The carbonation process is affected both by the concrete material properties such as W/C ratio, types of cement and aggregated, admixture characteristics and the environmental factors such as CO2 concentration, temperature, humidity. Based on results of preliminary research on carbonation, this study is to propose a carbonation prediction model by taking into account of prediction model by taking into account of CO2 concentration and W/C ratio among major factors affecting the carbonation process.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.669-674
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• 2003

The purpose of this study is to identify the diffusion coefficients of carbon dioxide for various concrete mixtures. The test results indicate that the diffusion coefficient increases with the increase of water-cement ratio. The diffusion coefficient decreases with the increase of relative humidity at the same water-cement ratio. The diffusion of carbon dioxide reached the steady-state within about five hours after exposure. It was found that the diffusion coefficient of cement paste is larger then that of concrete or mortar. The quantitative values of diffusivity of carbon dioxide in this study will allow more realistic assessment of carbonation depth in concrete structures.

• Korean Journal of Agricultural and Forest Meteorology
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• v.17 no.3
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• pp.207-216
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• 2015

The study was conducted to determine the effects of forest restoration methods and stand structure on solar radiation, air temperature, relative humidity, soil temperature, and soil water content, based on volume, in forest stand after forest fire. The changes of the micro-climate elements in naturally and artificially restored forest after forest fire were measured in Goseong and Samcheok, Gangwon province. Pinus spp. were commonly appeared in ridges, barren lands or planted areas of the study sites while the other areas were dominated by Quercus spp. In the early stage, trees in the naturally regenerated site grow better than the trees in artificially rehabilitated site. However, the growth ratio rapidly decreased by time passed in natural regeneration area. The environmental conditions (solar radiation, air temperature, relative humidity, soil temperature and soil water content) were significantly different by the regions and the methods (p<.05). However, the coefficients of variations of the environmental conditions were not significantly different at 95% confidence level. As the coverage and tree height in crown layer increased, the relative humidity and soil water content were increased while the temperature and solar radiation were decreased. Especially, the relative humidity, solar radiation, and soil water content were clearly affected by the tree height and coverage ratio ($R^2$ means from 0.628 to 0.924). Even though the data should have collected at least more than 5 years in meteorological analysis, the two year results show some clear relationship between forest structure and microclimate elements.

• Advances in environmental research
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• v.2 no.1
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• pp.61-80
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• 2013

Quantification of viable forms of microbial community (bacteria and fungi) using culture-dependent methods was done in order to characterize the indoor air quality (IAQ). Role of those factors, which may influence the concentration of viable counts of bacteria and fungi, like ventilation, occupancy, outdoor concentration and environmental parameters (temperature and relative humidity) were also determined. Volumetric-infiltration sampling technique was employed to collect air samples both inside and outside the schools. As regard of measurements of airborne viable culturable microflora of schools during one academic year, the level of TVMCs in school buildings was ranged between 803-5368 cfu/$m^3$. Viable counts of bacteria (VBCs) were constituted 63.7% of the mean total viable microbial counts where as viable counts of fungi (VFCs) formed 36.3% of the total. Mean a total viable microbial count (TVMCs) in three schools was 2491 cfu/$m^3$. Outdoor level of TVMCs was varied from 736-5855 cfu/$m^3$. Maximum and minimum VBCs were 3678-286 cfu/m3 respectively. Culturable fungal counts were ranged from 268-2089 cfu/$m^3$ in three schools. Significant positive correlation (p < 0.01) was indicated that indoor concentration of viable community reliant upon outdoor concentration. Temperature seemed to have a large effect (p < 0.05, p < 0.01) on the concentration of viable culturable microbial community rather than relative humidity. Consistent with the analysis and findings, the concentration of viable cultural counts of bacteria and fungi found indoors, were of several orders of magnitude, depending upon the potential of local, spatial and temporal factors, IO ratio appeared as a crucial indicator to identify the source of microbial contaminants.