• Journal of the Korean Institute of Landscape Architecture
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• v.50 no.1
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• pp.68-77
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• 2022

The human thermal environment in an apartment complex located in Seoul was quantitatively analyzed to devise methods to modify human heat-related stresses in landscape and urban planning. Microclimatic data (air temperature, relative humidity, wind speed, and short- and long-wave radiation) were collected at 6 locations [Apt-center, roof (cement), roof (grass), ground, playground, and a tree-lined road] in the late spring and summer, and the data were used to estimate the human thermal sensation, physiological equivalent temperature (PET) and universal thermal climate index (UTCI). As a result, the playground location had the highest thermal environment, and the roof (grass) location had the lowest. The mean difference between the two locations was 0.8-1.1℃ in air temperature, 1.8-4.0% in relative humidity, and 7.5-8.0℃ in mean radiant temperature. In open space locations, the wind speed was 0.4-0.5 ms-1 higher than others. Also, a wind tunnel effect happened at the Apt-center location during the afternoon. For the human thermal sensation, PET and UTCI, the mean differences between the playground and roof (grass) locations were: 5.2℃ (Max. 11.7℃) in late spring and 5.4℃ (Max. 18.1℃) in summer in PET; and 3.0℃ (Max. 6.1℃) in late spring and 2.6℃ (Max. 9.8℃) in summer in UTCI. The mean differences indicated a level change in PET and 1/2 level in UTCI, and the maximum differences showed greater changes, 2-3 levels in PET, and 1-1.5 levels in UTCI. Moreover, the roof (grass) location gave 4.6℃ PET reduction and a 2.5℃ UTCI reduction in late spring, and a 4.4℃ PET reduction and a 2.0℃ UTCI reduction in the summer when compared with the roof (cement) location, which results in a 2/3 level change in PET and a 1/3 level in UTCI. Green infrastructure locations [roof (grass), ground, and a tree-lined road] were not statistically significant in the reduction of PET and UTCI in thermal environment modifying effects. The implementation of green infrastructure, such as rooftop gardens, grass pavement, and street tree planting, should be adopted in landscape planning and be employed for human thermal environment modification.

• Korean Journal of Agricultural and Forest Meteorology
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• v.1 no.1
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• pp.41-51
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• 1999

This study was conducted to investigate the effects of local climatic conditions on the annual increment of Korean white pine planted in Gapyung and Yaungdong. For this, stand variables such as mean DBH, mean height, basal area per hectare, and volume per hectare by stand age were measured and summarized for each locality. Based on these statistics, annual increments for 8 years from stand age 10 to 18 were calculated for each of stand variables. A topoclimatological technique which makes use of empirical relationships between the topography and the weather in study sites was applied to produce normal estimates of monthly mean, maximum, minimum temperatures, relative humidity, precipitation, and hours of sunshine. Then, the yearly climatic variables from 1990 to 1997 for each study site were derived from the spatial interpolation procedures based on inverse- distance weighting of the observed deviation from the climatic normals at the nearest 11 standard weather stations. From these estimates, 17 weather variables such as warmth index, coldness index, index of aridity etc., which affect the tree growth, were computed on yearly base for each locality. The deviations of measured annual increments from the expected annual increments for 8 years based on yield table of Korean white pine were then correlated with and regressed on the yearly weather variables to examine effects of local climatic conditions on the growth. Gapyung area provides better conditions for the growth of Korean white pine in the early stage than Youngdong area. This indicates that the conditions such as low temperature, high relative humidity, and large amount of precipitation provide favor environment for the early growth of Korean white pine. A ccording to the correlation and regression an analysis using local climatic conditions and annual increments, the growth pattern of Gapyung area corresponds to this tendency. However, it was found that the relationship between annual increments and local climatic conditions in Youngdong area shows different tendency from Gapyung. These results mean that the yearly growth pattern could not sufficiently be explained by climatic conditions with high variance in yearly weather variables. In addition, the poor growth in Youngdong area might not only be affected by climatic conditions, but also by other environmental factors such as site quality.

• Journal of the Korean Institute of Landscape Architecture
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• v.45 no.6
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• pp.115-125
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• 2017

This study was to investigate the user's thermal environments under the pergola($L\;7,200{\times}W\;4,200{\times}H\;2,700mn$) covered with Wisteria floribunda(Willd.) DC. according to the variation of leaf area index(LAI). We carried out detailed measurements with two human-biometeorological stations on a popular square Jinju, Korea($N35^{\circ}10^{\prime}59.8^{{\prime}{\prime}}$, $E\;128^{\circ}05^{\prime}32.0^{{\prime}{\prime}}$, elevation: 38m). One of the stations stood under a pergola, while the other in the sun. The measurement spots were instrumented with microclimate monitoring stations to continuously measure air temperature and relative humidity, wind speed, shortwave and longwave radiation from the six cardinal directions at the height of 0.6m so as to calculate the Universal Thermal Climate Index(UTCI) from $9^{th}$ April to $27^{th}$ September 2017. The LAI was measured using the LAI-2200C Plant Canopy Analyzer. The analysis results of 18 day's 1 minute term human-biometeorological data absorbed by a man in sitting position from 10am to 4pm showed the following. During the whole observation period, daily average air temperatures under the pergola were respectively $0.7{\sim}2.3^{\circ}C$ lower compared with those in the sun, daily average wind speed and relative humidity under the pergola were respectively 0.17~0.38m/s and 0.4~3.1% higher compared with those in the sun. There was significant relationship in LAI, Julian day number and were expressed in the equation $y=-0.0004x^2+0.1719x-11.765(R^2=0.9897)$. The average $T_{mrt}$ under the pergola were $11.9{\sim}25.4^{\circ}C$ lower and maximum ${\Delta}T_{mrt}$ under the pergola were $24.1{\sim}30.2^{\circ}C$ when compared with those in the sun. There was significant relationship in LAI, reduction ratio(%) of daily average $T_{mrt}$ compared with those in the sun and was expressed in the equation $y=0.0678{\ln}(x)+0.3036(R^2=0.9454)$. The average UTCI under the pergola were $4.1{\sim}8.3^{\circ}C$ lower and maximum ${\Delta}UTCI$ under the pergola were $7.8{\sim}10.2^{\circ}C$ when compared with those in the sun. There was significant relationship in LAI, reduction ratio(%) of daily average UTCI compared with those in the sun and were expressed in the equation $y=0.0322{\ln}(x)+0.1538(R^2=0.8946)$. The shading by the pergola covered with vines was very effective for reducing daytime UTCI absorbed by a man in sitting position at summer largely through a reduction in mean radiant temperature from sun protection, lowering thermal stress from very strong(UTCI >$38^{\circ}C$) and strong(UTCI >$32^{\circ}C$) down to strong(UTCI >$32^{\circ}C$) and moderate(UTCI >$26^{\circ}C$). Therefore the pergola covered with vines used for shading outdoor spaces is essential to mitigate heat stress and can create better human thermal comfort especially in cities during summer. But the thermal environments under the pergola covered with vines during the heat wave supposed to user "very strong heat stress(UTCI>$38^{\circ}C$)". Therefore users must restrain themselves from outdoor activities during the heat waves.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.5
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• pp.739-746
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• 2016

A total of 152 pig farms were randomly selected from the five provinces in South Korea. During the experiment, the average temperature and relative humidity was $24.7^{\circ}C$ and 74% in summer and $2.4^{\circ}C$ and 53% in winter, respectively. The correlation between floor space allowance (FSA) and productivity index was analyzed, including non-productive sow days (NPD), number of weaners (NOW), survival rate (SR), appearance rate of A-grade pork (ARA), and days at a slaughter weight of 110 kg (d-SW) at different growth stages. The objectives of the present study were i) to determine the effect of FSA on the pig productivity index and ii) to suggest the minimum FSA for pigs based on scientific baseline data. For the pregnant sow, NPD could be decreased if pregnant sows were raised with a medium level (M) of FSA (3.10 to $3.67m^2/head$) while also keeping the pig house clean which improves hygiene, and operating the ventilation system properly. For the farrowing sows, the NOW tended to decrease as the FSA increased. Similarly, a high level of FSA (H) is significantly negative with weaner SR of farrowing sows (p-value = 0.017), indicating this FSA tends to depress SR. Therefore, a FSA of 2.30 to $6.40m^2/head$ (very low) could be appropriate for weaners because a limited space can provide a sense of security and protection from external interruptions. The opposite trend was observed that an increase in floor space (> $1.12m^2/head$ leads to increase the SR of growing pigs. For the fattening pigs, H level of FSA was negatively correlated with SR, but M level of FSA was positively correlated with SR, indicating that SR tended to increase with the FSA of 1.10 to $1.27m^2/head$. In contrast, ARA of male fattening pigs showed opposite results. H level of FSA (1.27 to $1.47m^2/head$) was suggested to increase productivity because ARA was most affected by H level of space allowance with positive correlation ($R^2=0.523$). The relationship between the FSA and d-SW of fattening pigs was hard to identify because of the low $R^2$ value. However, the farms that provided a relatively large floor space (1.27 to $1.54m^2/head$) during the winter period showed d-SW was significantly and negatively affected by FSA.

• Journal of Korean Ophthalmic Optics Society
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• v.21 no.3
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• pp.265-274
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• 2016

Purpose: The aim of this study was to evaluate relationship between worker's ophthalmoxerosis symptom and IAQ (Indoor Air Quality) variation after planting indoor plants at newly-built office building. Methods: We selected a new office building located in Sejong-si and occupants who work in the Office for study. The indoor air pollutant was investigated according to applying indoor plants. The indoor air quality of the new building was evaluated by measuring volatile organic compounds (VOCs), aldehydes, temperature and humidity. The level of dry eye symptoms was classified into normal, mild, moderate and severe by using the Ocular Surface Disease Index (OSDI). Results: There was VOCs' reduction effect according to placing indoor plants because the concentration of VOCs in newly-built government office (Sejong-si) was highly decreased when the indoor plants was placed at the office. The occupants' SBS (Sick Building Syndrome) symptoms score was gradually decreased in accordance with applying indoor plants. However, SBS symptoms score was increased when the office was not applied indoor plants. There was not statistical significance in workers' dry eye questionnaire results. Conclusions: There was reduction effect of indoor air pollutant in applied indoor plants office. Also, in case of questionnaire results of ophthalmoxerosis and SBS (Sick Building Syndrome) symptoms score were showed positive effect. This study is needed longer-term study because of complements of difference of individual sensitivity and there are some limitations due to field survey research.

• Journal of the Korean earth science society
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• v.30 no.6
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• pp.734-743
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• 2009

In order to examine how climatological condition can influence on urban scale particulate air pollutants, single and cross spectrum analysis have been performed to daily mean concentrations of particulate matters ($PM_{10}$) in Busan together with the climatological variables over the Asian dust source regions. Single power spectrum analysis of $PM_{10}$ concentrations in Busan shows that, aside from the typical and well-known periodicities, 3-4 year of peak periodicity of power spectrum density was identified. In cross spectrum analysis, this 3-4 year periodicity is found to have a strong positive correlation with the wind speed and pressure, and negative with the temperature and relative humidity, which is rather consistent with both characteristics of air mass during the Asian dust event whose periodicities have been recorded inter-annually over the Korean urban cities. Over the Asian dust source regions, $PM_{10}$ vs. precipitation shows no significant periodicity from the time series of precipitation data, but the periodicity of EDI (Effective Drought Index) shows some interannual variabilities ranging from 2 to 4 years over the various source regions, suggesting that, rather than precipitation itself, the EDI could be more closely associated with the occurrence frequency of Asian dust and interannual variability of urban particle concentrations in Korean cities.

• Journal of Bio-Environment Control
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• v.20 no.4
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• pp.304-310
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• 2011

To evaluate the effect of curing treatment using a newly developed simplified curing unit (SCU) on the physicochemical quality of stored sweet potatoes was investigated for six months. The SCU consisting of a heater, an air circulation fan, exhaust fans, and a humidifying duct was installed in a cold storage room where the harvested sweet potatoes were stacked. During the six days of curing treatment, air temperature and relative humidity in the storage room were set at $32^{\circ}C$ and 90%, respectively. Physical and chemical properties of sweet potatoes were measured at 1-month intervals from the first day of storage. McKinney index showing the incidence and severity of decay was 0.83% in the curing treatment, while that of untreated control was 5.08% over the same storing period. Firmness, soluble solids content, and dry matter content in the cured sweet potatoes were greater than those of untreated control. Moreover, the changes of skin color in uncured potatoes occurred rapidly than cured one which showed delay of skin discoloration during the long-term storage. Results suggest that the SCU treatment improves the physicochemical quality of stored sweet potatoes and extends their storability. Therefore, the SCU can be effectively used for curing treatment of sweet potatoes with a relatively low cost.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.6
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• pp.21-26
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• 2018

Thermoplastic starch (TPS) was prepared by mixing starch with glycerol as a plasticizer. The glycerol content ranged from 20 to 35 wt. % and TPS was prepared in a twin screw extruder. The shear viscosity, thermal and mechanical properties of the TPS were investigated. The viscosity of TPS exhibited typical shear thinning behavior: decreasing viscosity with increasing shear rate. The power index, n, increased with increasing glycerol content. This is because as the content of glycerol, a Newtonian fluid, increases, the viscosity behavior of the TPS becomes closer to that of a Newtonian fluid. The thermal behavior of TPS showed that starch and glycerol are miscible. In addition, when TPS was aged for more than one day at room temperature, TPS showed a partially miscible phase structure. The moisture absorbed into the TPS was assumed to change the phase behavior. The mechanical properties of TPS were found to be strongly dependent on the content of the plasticizer. Both the toughness and stiffness increased with increasing plasticizer content. DSC showed that this unusual result was due to the combined effect of humidity and the high amylose content in starch.

• Korean Journal of Plant Resources
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• v.19 no.2
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• pp.218-222
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• 2006

This experiment was conducted to investigate the effects of climatic factors varied due to the type of plastic house, cultural season and location in the house on the growth of cucumber plants grown by nutrient solution. There were two growing periods, summer culture and retarding culture, two types of plastic houses, 1-2W type house and post-less house. Air temperature, relative humidity and amount of solar radiation in the plastic houses were measured. Also, dry weight of leaves and stems, plant height, number of leaves per plant, leaf area per plant and fresh weight of fruits per plant were observed. Plant growth analysis were conducted and interrelationships between climatic factors and physiological characteristics were investigated. The results were as follows. There were no differences between the type of plastic houses in the average air temperature and average relative humidity in the plastic house, but amount of solar radiation in 1-2W type house was significantly higher than that of postless house. Daily cumulative solar radiation were highest in southwest side of 1-2W type house and northwest side of postless house. Plant height and number of leaves per plant were higher in summer culture than retarding culture, while leaf area per plant was higher in retarding culture than summer culture. Relative growth rate (RGR) showed highly significantly positive correlations with net assimilation rate (WAR) and leaf area ratio (LAR). Contribution of NAR to RGR was much higher than that of LAR. Crop growth rate (CGR) showed highly significantly positive correlations with leaf area index (LAI). It appeared that increase of LAI was important to increase productivity of cucumber. Average daily air temperature for the whole growing period showed highly significantly positive correlations with RGR and NAR. Furthermore, cumulative solar radiation for the whole growing period in retarded culture showed significantly positive correlation with RGR and NAR.

• Journal of Wetlands Research
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• v.19 no.1
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• pp.172-179
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• 2017

The purpose of this study is to analyze the current original habitat and to conserve the narrow-mouthed toad populations. For this study, we used 240 pitfall traps (30 cm height ${\times}$ 20 cm width) to catch the narrow-mouthed toads that inhabit in Myeongji-dong, Gangseo-gu, in Busan metropolitan city from August 2, 2013 to November 7, 2013. We measured the environmental characteristics (soil composition factors, soil moisture, Humidity, soil temperature) for the seven habitat patterns of narrow-mouthed toads based on vegetation types. Main habitats of narrow mouthed toads were flat grassland where grass and false acacia grew and there was wetland all over the place. When analyzing habitats that main habitats of narrow-mouthed toads prefer after selecting representative seven vegetation, it was found that the most narrow-mouthed toads were caught in amur silver grass colony while the least narrow-mouthed toads were caught in bare land. Totally, we caught 846 narrow-mouthed toads over 68 times, and released them into the newly constructed habitat after injection VIE-tag. It seems that the reason for which the least narrow mouthed toads were caught in bare land is that bare land is not suitable for narrow mouthed toads to protect themselves from strong sunlight and to hide themselves from natural enemy. We found that temperature had the greatest influence on activities of narrow mouthed toads and at temperature of less than $15.6^{\circ}C$. We also found that the activities of narrow mouthed toads were remarkably low and then temperature was below $15.6^{\circ}C$. It meant that narrow mouthed toads seemed to go into hibernation. From this research, we could find the prefer habitat after analyzing habitats for the narrow-mouthed toads and could suggest for construction for the better habitat of narrow-mouthed toads.