• Wind and Structures
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• v.15 no.6
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• pp.481-494
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• 2012

The greenhouse type metal structures are increasingly used in modern construction of livestock farms because they are less laborious to construct and they provide a more favorable microclimate for the growth of animals compared to conventional livestock structures. A key stress factor for metal structures is the wind. The external pressure coefficient ($c_{pe}$) is used for the calculation of the wind effect on the structures. A high pressure coefficient value leads to an increase of the construction weight and subsequently to an increase in the construction cost. The EC1 in conjunction with EN 13031-1:2001, which is specialized for greenhouses, gives values for this coefficient. This value must satisfy two requirements: the safety of the structure and a reduced construction cost. In this paper, the Navier - Stokes and continuity equations are solved numerically with the finite element method (Galerkin Method) in order to simulate the two dimensional, incompressible, viscous air flow over the vaulted roofs of single span and twin-span with eaves livestock greenhouses' structures, with a height of 4.5 meters and with length of span of 9.6 and 14 m. The simulation was carried out in a wind tunnel. The numerical results of pressure coefficients, as well as, the distribution of them are presented and compared with data from Eurocodes for wind actions (EC1, EN 13031-1:2001). The results of the numerical experiment were close to the values given by the Eurocodes mainly on the leeward area of the roof while on the windward area a further segmentation is suggested.

• Korean Journal of Human Ecology
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• v.18 no.5
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• pp.1087-1092
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• 2009

From the environmental adaptation point of view, the clothing habits made by the thermal sensation and clothing weight of elderly women have changed according to the thermal sensation and health condition. The purpose of this study was to obtain the basic data for developing healthy and comfortable clothing for elderly women. Clothing weight, thermal sensation, clothing microclimate, resistance to cold and heat of 198 elderly women in Taejeon were surveyed from October 9, 2007 to October 19, 2007. 1. Clothing weight per body surface area was $830.4g/m^2$ of total clothing weight, $242.8g/m^2$ of underwear clothing weight, $617.3g/m^2$ of outerwear clothing weight, $419.8g/m^2$ of upper clothing weight, and $420.4g/m^2$ of lower clothing weight. 2. More than 90% of the respondents replied that they felt comfortable when the temperature inside the clothing was $33.5^{\circ}C$ and humidity inside the clothing was 30.2%. 3. The elderly women were more sensible to cold than to hot, those who felt cold had a tendency to wear heavier clothing. 4. The appeal rate for physical pain of older and lower income people, especially those with an income under 1,000,000 won, was higher than that of others. On the other hand, the lower the subjective economic level, the younger they were, and the more the monthly average income was, the higher the rate of mental pain. 5. The heavier the total clothing weight was, the higher the appeal rate for general pain.

• KIEAE Journal
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• v.16 no.6
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• pp.51-56
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• 2016

Purpose: As declines in the quality of residential environments occur, such as urban heat island effect, tropical night phenomenon, and violations of right to light and privacy due to urban densification and high rise building, these problems are emerging as social issues. In order to improve these issues, design factors which consider environmental aspects must be selected when planning apartment complexes, and ways to reflect them in the planning phase must be explored. Method: In this study, the analytical hierarchy process(AHP) was used to deduce design factors that considered environmental elements during the planning of apartment complexes. Furthermore, the priority and weight for each evaluation index were assessed. The objective was to propose a guideline for planning apartment complexes by finding the best solution for each evaluation index using complex weight values. Result: Floor area ratio was selected as the most important evaluation criterion in the environmentally conscious evaluation index for apartment complex planning. The shape and placement of skylights were selected as the most important evaluation criteria in the sunshine environment for a pleasant residential environment. Ground surface cover design was selected as the most important criterion in the outdoor thermal environment index for improving the microclimate within cities and apartment complexes. Thus, the results of this study can serve as an investigation guideline that concerns policy and regulations, and as reference data that can be used in planning apartment complexes.

• Korean Journal of Environmental Biology
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• v.37 no.4
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• pp.618-624
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• 2019

This study aimed to determine the growth and carbon storage of planted Haloxylon aphyllum in the Aralkum Desert in Kazakhstan. Six sites afforested in 2000, 2005, 2009, 2010, 2013, and 2017 were selected. The root collar diameter(cm) and height(m) were measured for all H. aphyllum in 30 m×44 m plots. Biomass accumulation (g m^-2) and carbon storage(C g m^-2) were calculated using allometric equations and the carbon concentration data of Haloxylon species. The diameters varied from 2.5 cm to 4.3 cm and the height varied from 106.2 cm to 223.7 cm. The growth of H. aphyllum was not linearly related to the afforestation year or soil properties. Tree growth might have been influenced by variations in the microclimate, such as temperature, precipitation, and dust storms. The mean total biomass accumulation was 20.57g m^-2 and ranged from 2.42 g m^-2 to 64.53 g m^-2. The mean carbon storage was 9.70C g m^-2 and ranged from 1.12 C g m^-2 to 30.61 C g m^-2. These biomass and carbon storage estimates were smaller than those reported for other Central Asian deserts, but afforestation enabled the generation of vegetative cover and consequently, carbon sequestration in the manmade Aralkum Desert.

• Journal of the Korean Institute of Landscape Architecture
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• v.40 no.1
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• pp.1-11
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• 2012

Human thermal sensation based on a human energy balance model was analyzed in the study areas, the Changwon and Nanaimo sites, on clear days during thesummer of 2009. The climatic input data were air temperature, relative humidity, wind speed and solar and terrestrial radiation. The most effective factors for human thermal sensation were direct beam solar radiation, building view factor and wind speed. Shaded locations had much lower thermal sensation, slightly warm, than sunny locations, very hot. Also, narrow streets in the Nanaimo site had higher thermal sensation than open spaces because of greater reflected solar radiation and terrestrial radiation from their surrounding buildings. Calm wind speed also produced much higher thermal sensation, which reduced sensible and latent heat loss from the human body. By adopting climatic factors into landscape architecture, the human thermal sensation analysis method promises to help create thermally comfortable outdoor areas. The method can also be used for urban heat island modification and climate change studies.

• Korean Journal of Agricultural Science
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• v.46 no.3
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• pp.529-538
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• 2019

This study examined the changes in plant phenology of 12 woody species in Daegu University Forest, Gyeongsan-si, Gyeongsanbuk-do in 2007 and 2018. The Hobo was installed at a height of 1.2 meters to measure the microclimate such as air temperature and relative humidity to identify its effects on the changes in plant phenology. The number of trees surveyed were 42 individuals that included 12 species in 9 families, all of which are deciduous broad-leaved trees. The trends in temperature change in 2018 were similar to that in 2007, except for the temperatures in the warmest and coldest month. Compared to 2007, the average temperature of the warmest month in 2018 was $2.5^{\circ}C$ higher, and the coldest month was $3.3^{\circ}C$ lower. The lowest temperature from February to April in 2018 had the highest correlation with the blooming dates of the trees (r = 0.692) in 2018, and the highest temperature showed the lowest correlation (r = 0.392). The blooming date by species was significantly different (p < 0.05). The blooming date of 8 species (75%), including Prunus padus, was earlier by 1 to 16 days, while 4 species, such as Prunus armeniaca var. ansu, was later by 1 to 7 days in 2018 than that in 2007. However, the flowering duration did not have a significant effect on the plant phenology. The results can be used as basic data for long-term monitoring of plant phenology in the future, and follow-up studies on other environmental factors and physiological factors are needed.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.3
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• pp.158-166
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• 2019

Implementing proper land management techniques, such as selecting the best crops and applying the best cultivation techniques at the farm level, is an effective way for farmers to adapt to climate change. Also it will be helpful if the farmer can get the information of agro-weather and the growth status of cultivating crops in real time and the simulated results of applying optional technologies. To test this, a system (web site) was developed to produce agro-weather data and crop growth information of farms by combining agricultural climate maps and crop growth modeling techniques to highland area for summer-season Chinese cabbage production. The system has been shown to be a viable tool for producing farm-level information and providing it directly to farmers. Further improvements will be required in the speed of information access, the microclimate models for some meteorological factors, and the crop growth models to test different options.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.6
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• pp.811-815
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• 2006

The objective of this study was to evaluate the effect of electric fan installation for milk production improvement of dairy cattle in Thailand. The study was conducted using 2 small-holder dairy farms in Chiang Mai province, during April to August 2004. Electric fans were installed in front of each row of cows. Each of the two rows of cows in the barn was defined as an experimental unit, thus each farm had two experimental units. The fans were operated alternately in 7-day intervals between rows of cows within each farm during the day or between 8.00 am to 8.00 pm. Non-operation periods were used as control. Milk yields were recorded. Data on environmental temperature and humidity were obtained from Chiang Mai Meteorological Center. Result from statistically analysis of milk record suggested an interaction between lactation period and fan installation. Therefore, this interaction term of lactation period and fan installation (PERIOD_FAN) was added as a variable to the regression model. Due to the repeated data collection of milk yield from the same cow (alternate week), milk yield was analyzed by repeated measure analysis (Mixed model). Least square means were calculated for all levels and used to compare between each pair-wise values. The final data were collected from the total of 18 cows with 2,072 data. Overall means and SEM of milk yields and days in milk separated into farm were $14.7{\pm}0.06kg/day$ and $176.3{\pm}2.2days$, and $15.2{\pm}0.22kg/day$ and $202.5{\pm}3.7$ days for farm A and farm B, respectively. For multivariable analysis, only PERIOD_FAN and humidity were significantly associated with milk yield. Only the first period of lactation showed that the amount of milk yields during fan installation was higher than that of non-fan installation (p<0.05). Cows with fan installation produced approximately 1.2 kg/cow more milk than cows without fan installation during this period. In conclusion, the use of electric fan operated during the day time increased milk production of cows during the first period of lactation.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.6 no.3
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• pp.79-85
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• 2003

Human beings have pursued development and economic betterment; thus, enhancing convenience and prosperity. A flourish of human civilization upon the industrialization results a massive urbanization. However, human beings have connived the environmental importance in the course of rapid urbanization. The environmental quality now becomes one of the most important factors that determine the quality of life in a city. Many studies were proceeded about the heat island effect in large cities. In general, most studies have been done to investigate urban microclimate phenomena using meteorological network or AWS (automatic weather station) data. Those preceding studies do not seem to sufficiently reflect the and thus, failed to show regional representative. In this study, temporal Landsat TM satellite imageries of May 20, 1987 and May 21, 1999 were 뻐d in order to detect the surface temperature of the study area using the band 6 ($10.4{\mu}m{\sim}12.5{\mu}m$). The surface temperature distribution detected by the band 6 of Landsat TM was over layed with the land cover classification data in order to investigate the temperature difference of the paved road and the riparian areas of the stream. As a result, a surface temperature difference as much as $3^{\circ}C$ between the paved road and the riparian areas with vegetation was observed. This study concludes that the land cover change is one of the main causes of urban heat island effect which may be closely affected by the paved areas and roads. Besides, the change of the atmospheric temperature followed by the urban secular change could have been confirmed. In the case of Yangjaecheon stream which underwent a heavy environmental restoration in 1995, the temperature was decreased as much as $0.6^{\circ}C$ after the restoration. The results of this study is expected to contribute to develop an urban space in harmony with the healthy human life and the environment respecting the crucial role of vegetation to stabilize the urban environmental dynamics.

• Korean Journal of Agricultural and Forest Meteorology
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• v.21 no.3
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• pp.146-157
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• 2019

One of the most distinctive features of the South Korean rural environment is that the variation of weather or climate is large even within a small area due to complex terrains. The Geospatial Schemes based on Topo-Climatology (GSTP) was developed to simulate such variations effectively. In the present study, we reviewed the progress of the geospatial schemes for production of farm-scale agricultural weather data. Efforts have been made to improve the GSTP since 2000s. The schemes were used to provide climate information based on the current normal year and future climate scenarios at a landscape scale. The digital climate maps for the normal year include the maps of the monthly minimum temperature, maximum temperature, precipitation, and solar radiation in the past 30 years at 30 m or 270 m spatial resolution. Based on these digital climate maps, future climate change scenario maps were also produced at the high spatial resolution. These maps have been used for climate change impact assessment at the field scale by reprocessing them and transforming them into various forms. In the 2010s, the GSTP model was used to produce information for farm-specific weather conditions and weather forecast data on a landscape scale. The microclimate models of which the GSTP model consists have been improved to provide detailed weather condition data based on daily weather observation data in recent development. Using such daily data, the Early warning service for agrometeorological hazard has been developed to provide weather forecasts in real-time by processing a digital forecast and mid-term weather forecast data (KMA) at 30 m spatial resolution. Currently, daily minimum temperature, maximum temperature, precipitation, solar radiation quantity, and the duration of sunshine are forecasted as detailed weather conditions and forecast information. Moreover, based on farm-specific past-current-future weather information, growth information for various crops and agrometeorological disaster forecasts have been produced.