• Journal of the Korean association of regional geographers
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• v.23 no.2
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• pp.403-419
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• 2017

This study analyzed the forces to drive the change of urban green spaces in Daegu from 1989 to 2009. First, the loss and fragmentation of green spaces in the past 20 years were spatially identified by performing the hot spots analysis for the cell-based spatial metrics quantifying the size and diversity of green spaces. Next, seven drivers such as slope, distance to roads, land price, population density, ratios of residential, commercial, and industrial areas were selected based on the previous studies and the direction of the association between the loss and fragmentation of green spaces and seven drivers was analyzed with the stepwise logistic regression. Finally, the relative importance of the seven drivers and their interactions in the past 20 years were analyzed with the geographical detector. The results show that the loss of green spaces was concentrated on a part of the Anshim housing development district from 1989 to 2009 and green spaces were highly fragmented around the housing development districts such as Seongseo, Anshim, Dalseong-gun and Chilgok. The forces to drive the loss and fragmentation of green spaces in these areas were different at the administrative levels, but the drivers such as slope and ratios of residential and industrial areas were commonly significant. These drivers were positively correlated with largest patch index(LPI) quantifying the loss of green spaces while they were negatively correlated with Shannon's diversity index(SHDI) measuring the fragmentation of green spaces. In other words, the loss and fragmentation of urban green spaces in Daegu appeared around such regions with lower slope and lower ratios of residential and industrial areas. The relative importance of drivers for LPI was listed as ratio of industrial area, land price, and ratio of commercial area in descending order whereas that of drivers for SHDI was listed as ratio of industrial area, land price, and distance to roads in descending order. Also, the interaction between slope and ratio of residential area had a great impact on LPI and SHDI. The ratio of industrial area was a single driver to most significantly explain the loss and fragmentation of urban green spaces in Daegu in the past 20 years. The interaction between slope and ratio of residential area was greater than the independent influence of a single driver. This study will provide the base data to build a sustainable urban green policy for the city of Daegu in the near future.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.6
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• pp.765-770
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• 2017

Green tea (Camellia sinensis L.) is consumed as a popular beverage worldwide, particularly in Asia. In this study, the effects of green tea powder addition on the antioxidant activities and texture properties of cooked rice were investigated. Texture analysis was carried out by texture profile analysis. Total polyphenols and total flavonoids were determined using spectrophotometric methods, and antioxidative activities were determined based on DPPH and ABTS radical scavenging activities, reducing power, and lipid peroxidation inhibitory activity. Antioxidant contents and antioxidative activities increased with a higher amount of green tea powder. However, there was no difference in texture properties between cooked rice with green tea powder and the control group. In conclusion, addition of green tea powder to cooked rice would be useful to increase antioxidant contents and antioxidative activities without alteration of texture properties.

• Korean Chemical Engineering Research
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• v.58 no.4
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• pp.565-572
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• 2020

This study developed a software platform using machine learning of artificial intelligence to optimize the distillation column system. The distillation column is representative and core process in the petrochemical industry. Process stabilization is difficult due to various operating conditions and continuous process characteristics, and differences in process efficiency occur depending on operator skill. The process control based on the theoretical simulation was used to overcome this problem, but it has a limitation which it can't apply to complex processes and real-time systems. This study aims to develop an empirical simulation model based on machine learning and to suggest an optimal process operation method. The development of empirical simulations involves collecting big data from the actual process, feature extraction through data mining, and representative algorithm for the chemical process. Finally, the platform for the distillation column was developed with verification through a developed model and field tests. Through the developed platform, it is possible to predict the operating parameters and provided optimal operating conditions to achieve efficient process control. This study is the basic study applying the artificial intelligence machine learning technique for the chemical process. After application on a wide variety of processes and it can be utilized to the cornerstone of the smart factory of the industry 4.0.

• Research in Plant Disease
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• v.12 no.3
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• pp.260-266
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• 2006

Pythium blight caused by Pythium spp. is one of major diseases in putting green of golf course. In this study, microorganisms which are anatgonistic to Pythium aphanidermatum, a pathogen of pythium blight, were selected primary through in vitro tests, dual culture method and triple layer agar diffusion method. In vivo test against pythium blight were conducted to select the best candidate biocontrol microorganism by pot experiment in a plastic house. Bacillus subtilis GB-0365 was finally selected as a biocontrol agent against pythium blight. Relative Performance Indies(RPI) was used as a criterion of selecting potential biocontrol agent. B. subtilis GB-0365 showed resistance to major synthetic agrochemicals used in golf course. Alternative application of synthetic agrochemicals and B. subtilis GB-0365 was most effective to successfully contol pythium blight. B. subtilis GB-0365 suppressed the development of pythium bight of bentgrass by 56.4% as compared to non-treated control and its disease control efficacy was 60.9% of a synthetic fungicide Oxapro(WP) efficacy. B. subtilis GB-0365 has a potential to be a biocontrol agent for control of pythium blight.

• Korean Journal of Ecology and Environment
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• v.49 no.4
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• pp.320-333
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• 2016

This study was carried out to elucidate the development of unprecedented water-bloom caused by a single species of colonial green algae Eudorina elegans in the upstream area of the Seungchon weir located in the Yeongsan River from late April to May 2013. The Yeongsan River is typically regulated system and the waterbody is seriously enriched by both external and internal sources of nutrients. Seasonal algal outbreaks were highly probable due to various potential factors, such as the excessive nutrients contained in treated wastewater, slow current, high irradiation and temperature, in diatom (winter), green algae (spring) and bluegreen algae (summer). Spring green-tide was attributed to E. elegans with level up to $1,000mg\;m^{-3}$(>$50{\times}10^4cells\;mL^{-1}$). The bloom was exploded in the initial period of the algal development and after then gradually diminished with transporting to the downstream by the intermittent rainfall, resulting in rapid expansion of the distribution range. Although the pulsed-flows by the weir manipulation was applied to control algal bloom, they were not the countermeasures to solve the underlying problem, but rather there still was a remaining problem related to the impact of pulsed-flows on the downstream. The green-tide of E. elegans in this particular region of the Yeongsan River revealed the blooming characteristics of a colonial motile microalga, and fate of vanishing away by the succeeding episodic events of mesoscale rainfall. We believe that the results of the present study contribute to limno-ecological understanding of the green-tide caused by blue-green algae in the four major rivers, Korea.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.57 no.4
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• pp.343-352
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• 2012

This experiment was carried out to report some data such as survival rate, tetraploid production efficiency, and agronomic characteristics of offspring from the induced tetraploid by the colchicine treatment in rye. The colchicine was soaked with 0.05%, 12 hours in dark condition and at two growth stages (green seed and 2nd leaf stage) in diploid ryes. Flow cytometry (FC) was proved to be efficient and rapid tool for screening ploidy levels in rye, showing around 40 to 60 in DNA amount (DAP1) corresponding to diploid and 80 to 110 tetraploid. There were 18.5% of survival rate at green seed treatment and 78% at 2nd leaf stage in average of two rye cultivars, Gogu and Jogreen, but in reverse 50.9% and 1.1% in the ratio of tetraploid to total tillers among the plants survived, respectively, resulting in 9.42% of tetraploid production rate in green seed treatment and 0.86% at 2nd leaf stage, respectively. In green seed treatment, there were 33% of survival rate in Gogu, 4% in Jogreen in 1st year, but 56% in Gogu, 21% in Jogreen and 49% in Charmgreen, respectively. The rate of tetraploid to total spikes among survived was 53.7% in Gogu, 32.4% in Jogreen, and 50.9% in average in 1st year, and 64.1% in Gogu, 51.5% in Jogreen, 60% in Charmgreen, and 60.5% in average in 2nd year. In green seed treatment, tetraploid production rate (survival rate ${\times}$ tetraploid ratio ${\times}$ 100) was 17.7% in Gogu and 1.3% in Jogreen and 9.42% in average in 1st year, and 35.9% in Gogu, 10.8% in Jogreen, 29.4% in Charmgreen, and 25.4% in average of three diploid rye cultivars. By the colchicine treatment with 0.05% for 12 hours in Gogu and Jogreen, 35 tetraploid plants were obtained and they produced 2,673 seeds with 148 spikes. There were 3.3-4.4 in the number of spikes per plant, 15.6-18.3 in grain number per spike, and 37.6 g in Gogu and 46.8 g in Jogreen in the 1,000-grain weight.

• Korean Journal of Community Nutrition
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• v.11 no.1
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• pp.98-107
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• 2006

This study was performed to test food preferences of the Korean elderly for Korean elderly menu development. The elderly subjects preferred steamed rice cooked with 1.2 times water than that with 1.5 times water (p < 0.001) , whole rice grain gruel than the gruel with ground grain (p < 0.05) . Green tea powder gruels developed as a snack, there were no significant differences in the preference of the elderly between gruel with different contents of green tea powder (2, 3, $4\%$). The preferences of the salt concentration of the soup were tested by using soybean sprout soup and soybean paste soup. The elderly preferred 0.7 - $0.8\%$ salted bean sprout soup and $7\%$ soybean paste soup. The elderly preferred Kimchi cut in widths of 1 - 2 cm than that in 0.5 cm. The elderly preferred sweeter grape jam ($67\%$ vs. $50\%$ or $37\%$ sugar content) and were not concerned about chewing seeds. This result could be useful to develop menus for the elderly. (Korean J Community Nutrition 11 (1): 98$\sim$107, 2006)

• Journal of Korea Foundry Society
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• v.31 no.5
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• pp.288-292
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• 2011

In order to complement the drawbacks of quartz crucible such as fragile-like break and melt-leakage through open slit nozzle, a new PFC system has been developed using a common graphite crucible and plugging system. The u melt is fed on to the rotating a roll through slit nozzle by self-gravity. The new equipment was designed and manufactured successfully. An effort for optimizing all related parameter has been made. Then using the optimized parameters about 10 meters u foil having very thin thickness, which meets the target thickness of 130 ${\mu}m$ and enough width more than 60 mm could be made. The thickness homogeneity set improved, due to the lower eddy flowing of the melt flow the self-gravity feeding system.

• Korean Journal of Plant Resources
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• v.28 no.6
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• pp.734-742
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• 2015

The purpose of this research was to find the most appropriate process for making yacon leaf tea. We applied both green tea and black tea brewing and fermenting methods for producing yacon leaf tea. This research included consumer test and descriptive analysis of professional trained panel on yacon tea tastes and flavors. Both consumer test and descriptive evaluation preferred yacon tea produced by black tea brewing and fermenting methods because it tasted less bitter and had a sweet, delicate taste. According to orthogonal transformation resulting from varimax rotation, first principal component was positively affected by black tea brewing and fermenting methods, while it was negatively affected by green tea brewing and fermenting methods. As a result, the study concluded black tea brewing and fermenting methods were appropriate for producing yacon leaf tea.

• Journal of the Korean Association of Geographic Information Studies
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• v.18 no.2
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• pp.59-74
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• 2015

The purpose of this study is to analyze reasonable green area ratios for mitigating urban heat island considering various land use types. Land uses of 5 types such as single residential, multi residential, commercial area, public facility, and industrial area were considered. Green areas were extracted from the tree attribution of land cover. Effect of urban heat island was analysed by the surface temperature of ASTER thermal infrared radiance scanned daytime and nighttime. Mitigation effect of green area at daytime was higher than nighttime. Surface temperature of green area was low in single residential at daytime. But the difference of surface temperature by each land use type was small. The effect of surface temperature mitigation of green area was lower in industrial area. The results of reasonable green area ratios for mitigating urban heat island indicate that surface temperature was the lowest with green area ratio of 40~50% in single residential, multi residential, and commercial area at daytime. Surface temperature of nighttime was not changed much by green area ratios. Therefore, the results of this study will be suggested in urban development planning to construct effectively green area for mitigating urban heat island.