• Fashion & Textile Research Journal
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• v.2 no.5
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• pp.398-404
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• 2000

We examined the effect of individual sweating responses on thermoregulatory responses induced by heat of sorption, immediately after the onset of sweating. The present study consists of two experiments. In experiment 1, made of 100% cotton (C) and 100% polyester (P) clothing were exposed in the chamber at ambient temperature (Ta) of $27.2^{\circ}C$ and relative humidity (rh) raised from 50% to 95% at five different increase rates of environmental vapor pressure (VP). The increase rate of clothing surface temperature (Tcs), peak Tcs and peak time showed significant correlation with the increase rate of environmental VP in C-clothing (p<0.05). In experiment 2, seven female subjects were studied during leg water immersion ($35-41^{\circ}C$) for 70min in Ta of 27.2 and 50%rh. There were significant positive correlations in the increase rate of clothing microclimate VP vs. changes in Tcs, skin blood flow, mean skin temperature and mean body temperature (p<0.05). The present results showed that individual clothing microclimate VP had significant effects on thermoregulatory responses induced by heat of sorption wearing C ensembles.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.4
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• pp.473-482
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• 1997

Temperature, humidity and wetness duration were monitored for fully developed paddy rice canopies with 3 different structures induced by the seeding method(puddled-soil drill seeding, DS ; hand broadcasting, HB ; machine broadcasting, MB). Within-canopy air temperature averaged over "clear sky" hours during the study period(maximum tillering through heading) was lower than the screen temperature at a nearby standard weather station, especially in the night. The same trend was true for "overcast sky" hours except the diurnal distinction. Vapor pressure within the canopy was high during the daytime and low in the night, making the daytime deviation from outside the canopy more significant on clear days. Under the overcast sky, the canopy maintained a steady 5 to 10％ higher vapor pressure than the outside regardless of day or night. Daily maximum temperature was observed to be higher within the canopies with more leaf mass, making MB the highest, HB the lowest, and DS in between. Relative humidity was over 90％ in the night and dropped to 70％ in the mid-afternoon, but vapor pressure within the canopy was highest at around 13:00 LST. Dew point depression was lowest and, combined with the temperature, the relative humidity was highest in HB. Mean period of wetting duration was in the order of DS＞HB＞MB, while the dew point depression was greatest in DS.

• Korean Journal of Agricultural and Forest Meteorology
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• v.2 no.3
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• pp.87-94
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• 2000

To recommend adequate covering materials and shapes of rice nursery bed for mechanical transplanting rice seedling, measuring of microclimate inside the rice nursery protected by polyethylene tunnel type, polyester tunnel type, and polyester flat type was compared to that outside the nursery. The vapor pressure deficit inside the polyester tunnel and polyethylene tunnel was higher than that outside the tunnel during daytime on a sunny day. During daytime on cloudy with rain day, the vapor pressure deficit inside polyester tunnel was higher than that in polyethylene tunnel or outside the nursery tunnel. The heat fluxes in the rice nursery tunnel during daytime flowed more to the soil than to the outside tunnel. Amounts of soil heat fluxes in polyethylene tunnel were higher than in polyester flat and polyester tunnel. The vertical profile of air temperature inside the nursery tunnel came to inversion during daytime and was lapse during nighttime regardless weather condition. The maximum temperature inside the nursery tunnel were 47.2$^{\circ}C$ in polyethylene tunnel and 37.$0^{\circ}C$ in polyester tunnel which was 21.1$^{\circ}C$ and 10.9$^{\circ}C$ higher than outside the tunnels respectively on sunny day. On cloudy with rain day, the temperature inside nursery tunnel was higher 8.4$^{\circ}C$ and 4.$0^{\circ}C$ polyethylene and polyester tunnel respectively then outside. Daily temperature changes became larger in the polyethylene tunnel, polyester tunnel, and outside the nursery tunnel in order. The rice seedling growth in polyester tunnel was better than the other nursery beds.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.1
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• pp.228-238
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• 1996

The purpose of this study was to evaluate the effect of chacteristics of knit fabrics on the microclimate of the skin simulating system. To determine the effect of characteristics of knit fabrics, vapor state of sweat pulse was simulated in the closed system. Different contents of fibers such as cotton, wool and polyester with different yarn size and knit types were chosen for specimens. The changes of humidity and temperature of air layer in the simulated systems were measured. Buffering indices, $K_d$ and $\beta_r$, were determined by considering $\alpha_p, \DeltaP_{max}, t_{max}, and tan\beta$. Physical properties of knit fabrics such as thickness, porosity, air resistance and moisture vapor transport were measured. Results showed that vapor pressure of wool was lower than cotton or polyester This was attributed to the hydrophilicity of wool which absorbed moisture rather quickly and retained in the knit fabric. The time to decrease vapor pressure was faster for polyester than cotton or wool. As a result, $K_d$ was in the order of wool> polye, item> cotton. $\beta_r$ of wool was rower than cotton or polyester due to its lowers porosity and slower desorption rate. For the yarn size, $K_d$ was in the order of 80's> 60's> 30's; thinner and lighter yarn showed better water vapor transport property. For knit type, buffering capacity of single jersey was better than interlock knit fabric. Statistical analysis showed that the air permeability was the most influential factor far the water vapor transport properties.

• Journal of the Korean Society of Clothing and Textiles
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• v.41 no.5
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• pp.929-938
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• 2017

This research investigated the effects of cool touch fabrics on thermo-regulating physical properties and subjective evaluation using a 3D fitted women's T-shirts in wear test. Qmax, clothing microclimate, microclimate wettedness, thermogram and subjective vote were observed during rest-right after an exercise-rest protocol. As a result, there was no single determining physical variable to explain the reasons of cool sensations of T-shirts made of cool touch fabric across the entire protocol. Qmax could partly predict a wear sensation at the initial stage when only insensible perspiration was presented. Simultaneous observation of temperature/humidity gradient understand from the inside to the outside of the clothing layer or microclimate wettedness calculated using vapor pressure were helpful to figure out the performance of cool touch fabric, especially at the later stage of the protocol when sweating was excessive. It was especially difficult to connect thermo-regulating physical variables to the subjective evaluation during transient conditions such as 'right after exercise' stage. It is necessary to measure the amount of heat and moisture transferred from the skin to the outside of clothing along with the physical properties measured in this study to understand the detailed mechanisms of why a cool sensation is evoked from tight fitting T-shirts made of newly developed cool touch fabrics.

• Journal of Biosystems Engineering
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• v.42 no.1
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• pp.23-43
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• 2017

Purpose: As application-specific wireless sensor networks are gaining popularity, this paper discusses the development and field performance of the GHAN, a greenhouse area network system to monitor, control, and access greenhouse microenvironments. GHAN, which is an upgraded system, has many new functions. It is an intelligent wireless sensor and actuator network (WSAN) system for next-generation greenhouses, which enhances the state of the art of greenhouse automation systems and helps growers by providing them valuable information not available otherwise. Apart from providing online spatial and temporal monitoring of the greenhouse microclimate, GHAN has a modified vapor pressure deficit (VPD) fuzzy controller with an adaptive-selective mechanism that provides better control of the greenhouse crop VPD with energy optimization. Using the latest soil-matrix potential sensors, the GHAN system also ascertains when, where, and how much to irrigate and spatially manages the irrigation schedule within the greenhouse grids. Further, given the need to understand the microclimate control dynamics of a greenhouse during the crop season or a specific time, a statistical assessment tool to estimate the degree of optimality and spatial variability is proposed and implemented. Methods: Apart from the development work, the system was field-tested in a commercial greenhouse situated in the region of Punjab, India, under different outside weather conditions for a long period of time. Conclusions: Day results of the greenhouse microclimate control dynamics were recorded and analyzed, and they proved the successful operation of the system in keeping the greenhouse climate optimal and uniform most of the time, with high control performance.

• Korean Journal of Medicinal Crop Science
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• v.26 no.6
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• pp.490-497
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• 2018

Background: The growth process of ginseng seedlings is very important in producing good quality ginseng. This study was carried out to investigate the effects of different microclimates on the growth characteristics of ginseng seedlings in a multi-layer bed facility. Methods and Results: Ginseng seedlings were cultivated in a three-layer bed facility. The air temperatures on the first and second floors were similar, while that on the third floor was about $1-4^{\circ}C$ higher than that on the other floors. The vapor pressure deficit (VPD) was higher inside than on the outside of the facility, and that on third floor was the highest in the multi-layer bed system. The photosynthetic rate, chlorophyll fluorescence, and growth characteristics of ginseng seedlings did not significantly differ among the three floors. The yield of ginseng seedlings was the highest at $721g/1.62m^2$ on the first floor. Conclusions: It was found that microclimate plays an important role in growing ginseng seedlings in multi-layer bed facilities, and therefore proper environmental control is important. In addition, producing ginseng seedlings using multi-layer bed facilities is a technology that is expected to provide a way to overcome climate change and stabilize ginseng production.

• The Korean Journal of Community Living Science
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• v.25 no.4
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• pp.549-556
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• 2014

This study evaluates the thermal insulation and evaporative resistance of a waterproof and breathable garment system and determines the factors influencing its thermal performance. The experimental garments were composed of underwear (shirts with 100% wool and 100% polyester) and outerwear (jackets and pants with a vapor-permeable membrane and a vapor-impermeable membrane). Data on clothing insulation in a dry condition ($10^{\circ}C$) and a wet condition ($10^{\circ}C$, 40% R.H.), evaporative resistance ($34^{\circ}C$, 40% R.H., and $10^{\circ}C$, 40% R.H.), and microclimate vapor pressure were collected and analyzed. According to the results, the thermal insulation of the experimental garment system ranged 1.27~1.40 in the dry condition and 0.40~0.89 in the wet condition at $10^{\circ}C$. Evaporative resistance ranged $41{\sim}525m^2Pa/W$. A decrease in thermal insulation by wetting underwear ranged 31~67% in the cold condition ($10^{\circ}C$). The breathability of the outer garment influenced the decrease in thermal insulation by wetting. The type of underwear fiber influenced the decrease in thermal insulation only when it was used with breathable outerwear. The vapor-permeable outerwear sample with polyester underwear (P_Perm) showed a larger decrease in insulation than that with wool (W_Perm). The evaporative resistance of the vapor-permeable ensemble showed no effect of underwear in the warm condition ($34^{\circ}C$), but polyester underwear showed lower evaporative resistance than wool in the cold condition ($10^{\circ}C$). The vapor-impermeable ensemble showed no difference in evaporative resistance between polyester underwear and wool underwear in both conditions. Future research should consider various clothing ensemble combinations and environmental conditions and evaluate wear comfort by using human subjects.

• Korean Journal of Agricultural and Forest Meteorology
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• v.7 no.1
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• pp.35-44
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• 2005

Microclimate of Gwangneung forest watershed is characterized by analyzing wind, radiation, profiles of air temperature and humidity, soil and bole temperature, precipitation and soil water content measured at and around the flux tower from April 2000 to September 2003. Mountain-valley wind was prevalent due to the topographic effect with dominant wind from east during daytime and relatively weak wind from west during nighttime. Air temperature reaches its peak in July-August whereas monthly-averaged incoming shortwave radiation shows its peak in May due to summer monsoon. Albedo ranges from 0.12 to 0.16 during the growing season. Monthly-averaged bole temperature is in phase with monthly- averaged air temperature which is consistently higher. Monthly-averaged soil temperature lags behind air temperature and becomes higher with leaf fall. With the emergence of leafage in April, maximum temperature level during midday shifts from the ground surface to the crown level of 15-20m in May. Profiles of water vapor pressure show a similar shift in May but the ground surface remains as the major source of water. Vapor pressure deficit is highest in spring and lowest in winter. Monthly averaged surface soil temperatures range from 0 to 20℃ with a maximum in August. Monthly averaged trunk temperatures of the dominant tree species range from -5.8 to 21.6℃ with their seasonal variation and the magnitudes similar to those of air temperature. Annual precipitation amount varies significantly from year to year, of which >60% is from July and August. Vertical profiles of soil moisture show different characteristics that may suggest an important role of lateral movement of soil water associated with rainfall events.

• Journal of Bio-Environment Control
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• v.6 no.3
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• pp.205-215
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• 1997

An accurate transpiration model for greenhouse tomato crop, which is liable to transpiration depression and yield loss because of low solar radiation and high humidity, could be an efficient tool for the optimum control of greenhouse climate and for the optimization of Irrigation scheduling. The purpose of this study was to develop transpiration model of greenhouse tomato and to carry out the experimental verification. The formulas to calculate the canopy transpiration and temperature simultaneously were derived from the energy balance of canopy. Transpiration and microclimate variables such as net radiation, solar radiation, humidity, canopy and air temperature, etc. were simultaneously measured to estimate parameters of model equations and to verify the suggested model. Leaf boundary layer resistance was calculated as a function of Nusselt number and stomatal diffusive resistance was parameterized by solar radiation and leaf-air vapor pressure deficit. The equation for stomatal diffusive resistance could explain more than 80％ of its variation and the calculated stomatal diffusive resistance showed good agreements with the measured values in situations independent of which the constants of the equation were estimated. The canopy net radiation calculated by Stanghellini's model with slight modification agreed well with the measured values. The present transpiration model, into which afore-mentioned component equations were assembled, was found to predict the canopy temperature, instantaneous and daily transpiration with considerable accuracy in greenhouse climates.