• Journal of Environmental Science International
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• v.21 no.4
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• pp.535-543
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• 2012

The aerosol number concentration have measured with an aerodynamic particle sizer spectrometer(APS) at Gosan site, which is known as background area in Korea, from January to September 2011. The temporal variation and the size distribution of aerosol number concentration have been investigated. The entire averaged aerosol number concentration in the size range 0.25~32.0 ${\mu}m$ is about 252 particles/$cm^3$. The number concentration in small size ranges(${\leq}0.5{\mu}m$) are very higher than those in large size ranges, such as, the number concentration in range of larger than 6.5 ${\mu}m$ are almost zero particles/$cm^3$. The contributions of the number concentration to PM10 and/or PM2.5 are about 34%, 20.1% and 20.4% in the size range 0.25~0.28 ${\mu}m$, 0.28~0.30 ${\mu}m$ and 0.30~0.35 ${\mu}m$, respectively, however, the contributions are below 1% in range of larger than 0.58 ${\mu}m$. The monthly variations in the number concentration in smaller size range(<1.0 ${\mu}m$) are evidently different from the variations in range of larger than 1.0 ${\mu}m$, but the variations are appeared similar patterns in smaller size range(<1.0 ${\mu}m$), also the variations in range of larger than 1.0 ${\mu}m$ are similar too. The diurnal variations in the number concentration for smaller particle(<1.0 ${\mu}m$) are not much, but the variations for larger particle are very evident. Size-fractioned aerosol number concentrations are dramatically decreased with increased particle size. The monthly differences in the size-fractioned number concentrations for smaller size range(<0.7 ${\mu}m$) are not observed, however, the remarkable monthly differences are observed for larger size than 0.7 ${\mu}m$.

• Journal of the Korea Fashion and Costume Design Association
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• v.24 no.3
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• pp.145-158
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• 2022

To grasp the size system of children's clothing online shopping malls, basic size charts for clothing products from 14 shopping malls were collected, compared, and analyzed. Looking at the age range of the basic size chart for each company, the minimum age is 1 year old, the maximum age is 14-15 years old, and all companies included ages up to 7 years. In addition, as for the number of size designations, children's clothing companies used seven to eight designations, and there were six types of size designation methods. Next, looking at the height range for each size, even with the same size designation method, the height range differed depending on the company. Also, the KS size standard does not consider body weight, but many companies use weight as a reference body size. Compared with the child body size data of the 6th Korean Body Size Data, the height and weight range for each size provided by the company showed differences between companies. The results of this study can be used in the future as basic data when revising and supplementing the clothing sizes in children's clothing companies.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• v.4 no.3
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• pp.115-126
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• 2023

Understanding the carrying capacity of a habitat is crucial for effectively managing populations of wild boars (Sus scrofa), which are designated as harmful wild animal species in national parks. Carrying capacity refers to the maximum population size supported by a park's environmental conditions. This study aimed to estimate the appropriate wild boar population size by integrating population characteristics and habitat suitability for wild boars in the Bukhansan National Park using the HexSim program. Population characteristics included age, survival, reproduction, and movement. Habitat suitability, which reflects prospecting and resource acquisition, was determined using the Maximum Entropy model. This study found that the optimal population size for wild boar ranged from 217 to 254 individuals. The population size varied depending on the amount of resources available within the home range, indicating fewer individuals in a larger home range. The estimated wild boar population size was 217 individuals for the minimum amount of resources (50% minimum convex polygon [MCP] home range), 225 individuals for the average amount of resources (95% MCP home range), and 254 individuals for the maximum amount of resources (100% MCP home range). The results of one-way analysis of variance revealed a significant difference in wild boar population size based on the amount of resources within the home range. These findings provide a basis for the development and implementation of effective management strategies for wild boar populations.

• Journal of Environmental Health Sciences
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• v.47 no.2
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• pp.175-181
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• 2021

Objectives: The correlation between the size of a leak hole, the volume of the leakage, and the range of influence was investigated for a hydrochloric acid tank-lorry. Methods: For the case of a tank-lorry chemical accident, KORA (Korea Off-site Risk Assessment Supporting Tool) was used to predict the leak rate and the range of influence according to the size of the leak hole. The correlation was studied using R. Results: As a result of analyzing the leak rate change according to the leak hole size in a 35% hydrochloric acid tank-lorry, as the size of the leak hole increased from 1 to 100 mm, the leak rate increased from 0.008 to 83.94 kg/sec, following the power function. As a result of calculating the range of influence under conditions ranging from 1 to 100 mm in size and 10 to 60 minutes of leakage time, it was found that the range spanned from a minimum of 5.4 m to a maximum of 307.9 m. As a result of multiple regression analysis using R, the quadratic function model best explained the correlation between the size of the leak hole, the leak time, and the range of influence with an adjected coefficient of determination of 0.97 and a root mean square error of 22.33. Conclusion: If a correlation database for the size of a leak hole is accumulated for various substances and under various conditions, the amount of leakage and the range of influence can easily be calculated, facilitating field response activities.

• Korean Journal of Food Science and Technology
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• v.25 no.5
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• pp.541-545
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• 1993

Two different methods (Sieve shaker, Elzone particle size analyzer) were used to investigate rice flour particle size obtained by various milling method. Results of Elzone particle size analyzer were more effective than Sieve shaker in determining particle size, and the distribution of particle size of rice flours was affected by the type of the milling methods used. A rice flour, prepared in a Pin mill had a particle size range of $60{\sim}500$ mesh, and 30.38% of the sample was in the particle size range $200{\sim}270$ mesh. A rice flour, prepared in a Colloid mill had a particle size range of $40{\sim}500$ mesh and more of flour particles appeared in the range $140{\sim}200$ mesh than any other particle size. A rice flour, prepared in a Micro mill had a particle size range of $140{\sim}500$ mesh, and 41.62% of the sample was in the particle size range over 500 mesh. A rife flour, prepared in a Jet mill had a finer flour particle size was over the particle size range 500 mesh. The finer rice flour gave the highest L value and the lowest a value. The wet-milled flour particles were observed as a cluster of starch granules and the particles of rice flour (dry-milling) were observed as fragment of rice grains. Scanning Electron Photomicrographs revealed that visual differences in structure between milling methods, and similar results with Elzone particle size analyzer method in particle size.

• Journal of the Korean Society of Clothing and Textiles
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• v.40 no.2
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• pp.330-341
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• 2016

This study suggested criterion for Petite-size and analyzed the body size and characteristics that were proper to manufacture clothing for Korean Petite-size women aged 18 to 34. It also analyzed size information about pattern making for Petite-size women through a comparison of the size and proportion of Petite-size with Regular-size. The criterion of Petite-size was decided in consideration of the distribution and perception of stature; subsequently, the stature range for Petite-size was defined as under 157.5cm. Body size and proportion of Petite-size were analyzed through calculating the mean from 25 to 75 percentiles of a Petite-size stature range. The Petite-size of this study was compared to KS Petite and total subjects through One way ANOVA. It was confirmed that the Petite-size of this study had body characteristics like KS Petite; however, Petite-size was larger in height and vertical length than KS Petite. The significant differences between Petite-size and Regular-size were identified in the same bust girth range, that required a revised calculation formula for pattern making that would be proper for Petite-size. It is expected that the Body size and proportion could be utilized as a reference for manufacturing or purchasing Petite-size clothing. The result of this study will contribute to enhance the fit satisfaction for Petite-size women aged 18 to 34.

• Journal of Environmental Science International
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• v.21 no.1
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• pp.23-30
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• 2012

The aerosol number concentration have measured with an aerodynamic particle sizer spectrometer(APS) at Gosan site in Jeju, Korea, from March 2010 to March 2011. And then the atmospheric aerosol number concentration, the temporal variation and the size distribution of aerosol number concentration have been investigated. The aerosol number concentration varies significantly from 748 particles/$cm^3$ to zero particles/$cm^3$. The average number concentration in small size ranges are very higher than those in large size ranges. The number concentrations in the size range 0.25~0.28 ${\mu}m$, 0.40~0.45 ${\mu}m$ and 2.0~2.5 ${\mu}m$ are about 84 particles/$cm^3$, 2 particles/$cm^3$ and 0.4 particles/$cm^3$, respectively. The number concentrations in range of larger than 7.5 ${\mu}m$ are below 0.001 particles/$cm^3$. The seasonal variations in the number concentration for smaller particle(<1.0 ${\mu}m$) are not much, but the variations for larger particle are very evident. And strong amplitudes of diurnal variations of entire averaged aerosol number concentration are not observed. Size-fractioned aerosol number concentrations are dramatically decreased with increased particle size. The size-fractioned aerosol number concentrations in size range 0.8~4.0 ${\mu}m$ during nighttime are evidently higher than during daytime, but similar levels are appeared in other size range. The seasonal differences in the size-fractioned number concentrations for smaller size range(<0.7 ${\mu}m$) are not observed, however, the remarkable seasonal differences are observed for larger size than 0.7 ${\mu}m$.

• Journal of Environmental Science International
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• v.22 no.3
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• pp.347-358
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• 2013

The aerosol number concentration have measured with an aerodynamic particle sizer spectrometer(APS) at Gosan in Jeju Island, which is known as background area in Korea, from March 2010 to February 2011. The obtained results of asian dust events and non-asian dust period have been compared. The results show that the entire averaged aerosol number concentration from APS measurement during asian dust events and non-asian dust period are about 341 particles/$cm^3$ and 240 particles/$cm^3$, respectively. During asian dust events, the number concentration in small size ranges(${\leq}0.4{\mu}m$) are similar to non-asian dust period, however, those in large size ranges(${\geq}0.7{\mu}m$) are very higher than non-asian dust period. The contributions of the size resolved number concentration(23 channel in $0.25{\sim}10.0{\mu}m$) to total number concentration in that range are dramatically decreased with increased particle size. The contributions of smaller size ranges(${\leq}0.4{\mu}m$) during asian dust events are very low compared with non-asian dust period, on the other hand, those of larger size ranges(${\geq}0.4{\mu}m$) are higher than non-asian dust period. The number concentration in each size range are strongly correlated with the concentration in adjacent size range. And the total aerosol number concentration are depended on the number concentration in range of smaller than $0.58{\mu}m$ during non-asian dust period and asian dust events. On the other hand, $PM_{10}$ mass concentration has mainly affected with the number concentration in range of smaller than $1.0{\mu}m$ during non-asian dust period, however, during asian dust events, the mass concentration has mainly affected with the number concentration in range of $0.65{\sim}3.0{\mu}m$.

• Journal of Ecology and Environment
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• v.34 no.4
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• pp.365-370
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• 2011

The water deer (Hydropotes inermis) is one of the most primitive extant deer of the family Cervidae. Unlike Chinese water deer, Korean water deer have rarely been studied, even though they have relatively well remained in Korea. In particular, the home range of the Korean water deer has not yet been studied. Here we estimated the home range of the Korean water deer using two different methods (GPS and radio tracking) and analyzed the home range according to sex, time, and season. The mean home range size of four individuals was 2.77 $km^2$ and 0.34 $km^2$ under the 95% minimum convex polygon (MCP) and the 50% kernel (K) method, respectively. There seemed to be a difference in home range size between males (3.30 $km^2$) and females (2.25 $km^2$) under the 95% MCP method. We also found a difference in home range size between day (1.90 $km^2$) and night (2.43 $km^2$) by 95% MCP method. In addition, a home range size difference was observed between summer (4.65 $km^2$) and spring (0.48 $km^2$) or fall (0.85 $km^2$) using the 95% MCP method. Water deer seemed to have a larger home range in night than in day, and males also have a larger home range. We presumed that the GPS tracking method of the code division multiple access system could be a very useful tool for understanding the ecology of the water deer using the radio tracking method. Using these tracking methods and through future research, we can better understand the habitat use pattern of these water deer.

• Journal of the Korea Institute of Military Science and Technology
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• v.27 no.3
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• pp.355-363
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• 2024

This study proposes a method for determining the optimal target size for an artillery range considering ballistics and environmental conditions. To this end, the size of the probable error of each type of ammunition and charge determined during shooting were considered, and the effect of the firing position and target terrain characteristics on the target size was analyzed. In conclusion, the size of the target increased as the range increased, and a larger target size was required for the DPICM than for the general high explosive. Accordingly, the optimal target size must be determined by considering various factors such as topographical characteristics, shooting position location, and shooting range safety standards.