• Korean Journal of Agricultural Science
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• v.47 no.2
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• pp.349-360
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• 2020

Fire-blight disease is a kind of contagious disease affecting apples, pears, and some other members of the family Rosaceae. Due to its extremely strong infectivity, once an orchard is confirmed to be infected, all of the orchards located within 100 m must be buried under the ground, and the sites are prohibited to cultivate any fruit trees for 5 years. In South Korea, fire-blight was confirmed for the first time in the Ansung area in 2015, and the infection is still being identified every year. Traditional approaches to detect fire-blight are expensive and require much time, additionally, also the inspectors have the potential to transmit the pathogen, Thus, it is necessary to develop a remote, unmanned monitoring system for fire-blight to prevent the spread of the disease. This study was conducted to detect fire-blight on pear trees using discriminant analysis with color information collected from a rotary-wing drone. The images of the infected trees were obtained at a pear orchard in Cheonan using an RGB camera attached to a rotary-wing drone at an altitude of 4 m, and also using a smart phone RGB camera on the ground. RGB and Lab color spaces and discriminant analysis were used to develop the image processing algorithm. As a result, the proposed method had an accuracy of approximately 75% although the system still requires many flaws to be improved.

• Journal of Microbiology and Biotechnology
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• v.22 no.10
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• pp.1359-1366
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• 2012

A strain of Streptomyces cavourensis subsp. cavourensis (coded as SY224) antagonistic to Colletotrichum gloeosporioides infecting pepper plants was isolated. SY224 produced lytic enzymes such as chitinase, ${\beta}$-1,3-glucanase, lipase, and protease in respective assays. To examine for antifungal activity, the treatments amended with the nonsterilized supernatant resulted in the highest growth inhibition rate of about 92.9% and 87.4% at concentrations of 30% and 10%, respectively. However, the sterilized treatments (autoclaved or chloroform treated) gave a lowered but significant inhibitory effect of about 63.4% and 62.6% for the 10% supernatant concentration, and 75.2% and 74.8% for the of 30% supernatant concentration in the PDA agar medium, respectively, indicative of the role of a non-protein, heat stable compound on the overall effect. This antifungal compound, which inhibited spore germination and altered hyphal morphology, was extracted by EtOAc and purified by ODS, silica gel, Sephadex LH-20 column, and HPLC, where an active fraction was confirmed to be 2-furancarboxaldehyde by GS-CI MS techniques. These results suggested that SY224 had a high potential in the biocontrol of anthracnose in pepper, mainly due to a combined effect of lytic enzymes and a non-protein, heat-stable antifungal compound, 2-furancarboxaldehyde.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.4
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• pp.650-656
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• 2011

Lysobacter antibioticus HS124 isolated from pepper rhizosphere soil produced catechol type siderophore. Purified siderophore by Diaion HP-20 and silica gel column chromatography showed several hydroxyl functional groups adjacent to benzene rings by analysis of $^1H$ NMR spectroscopy. The strain HS124 showed different activities to suppress Phytophthora capsici with different concentrations of exogenous Fe (III) in minimal medium where antifungal activity with $100{\mu}M$ Fe (III) was approximately 1.5 times higher than in absence of Fe (III). Bacterial population in this Fe (III)-amended medium was also highest with $8.9{\times}10^8\;CFU\;ml^{-1}$ which also corresponded to the strongest siderophore activity. When grown in rich medium (minimal medium with N, $P_2O_5K_2O$ and glucose), HS124 exhibited approximately 2 times stronger antifungal activity compared to minimal medium. In pot trials, treatments of bacterial culture grown in rich medium with (C1) or without (C2) $100{\mu}M$ Fe (III) exhibited a high protection of pepper plants from disease, compared to medium only with (M1) or without (M2) $100{\mu}M$ Fe (III). Especially, treatment C1 showed the best disease control effect of about 70 %. Thus, the strain HS124 should be recommended as a potential biocontrol agent against P. capsici in pepper.

• Korean Journal of Food Science and Technology
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• v.30 no.4
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• pp.983-987
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• 1998

Effects of sugars, temperature, pH and some chemicals on caramelization were investigated for improving of its reaction rates. Among the sugars tested, fructose showed the fastest reaction rate, followed by sucrose, glucose, starch syrup and maltose. As the reaction temperature increased from 80 to $110^{\circ}C$, the rate greatly increased by the range of $150{\sim}8000$ folds depending on sugars. It was indicated that pH 10 resulted in the highest reaction rate in the range of $pH{\;}4{\sim}10$. When several chemicals, such as phosphates and organic acid salts, were added to starch syrup, the rate increased by more than 10 folds, in particular effects of $K_2HPO_4$ and sodium salts of citrate, oxalate and succinate were significant.

• Journal of the Korean Society of Hazard Mitigation
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• v.9 no.1
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• pp.145-150
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• 2009

Because it is difficult to install new large hydraulic structure, washland is considered as alternatives of hydraulic facility. As flood reduction effect of washland is dependent on flood, hydrograph, capacity of washland and spillway height, applying adequate spillway height is very important to maximize flood reduction effect of washland. In this study, effect of variation of spillway height on flood reduction effect of washlands is analyzed. The existing model developed to make decision for optimal location of washland using flood reduction effect as evaluation function and location of washland as decision variable was revised for this purpose. The spillway height of washland is added as decision variable and revised model finally give optimal location and spillway height of washland as result. The developed model has been applied to the Ansung River basin and application result was compared with that of existing model. The application result shows that developed model can give more efficient result than existing model.

• Korean Journal of Remote Sensing
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• v.23 no.6
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• pp.521-528
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• 2007

The overall objective of this research was to investigate various combination of segmentation parameters and to improve classification accuracy of object-oriented classification. This research presents a method for evaluation of segmentation parameters by calculating Moran's I and Intrasegment Variance. This research used Landsat-7/ETM image of $11{\times}14$ Km developed area in Ansung, Korea. Segmented images are generated by 75 combinations of parameter. Selecting 7 combinations of high, middle and low grade expected classification accuracy was based on calculated Moran's I and Intrasegment Variance. Selected segmentation images are classified 4 classes and analyzed classification accuracy according to method of objected-oriented classification. The research result proved that classification accuracy is related to segmentation parameters. The case of high grade of expected classification accuracy showed more than 85% overall accuracy. On the other hand, low ado showed around 50% overall accuracy.

• Korean Journal of Soil Science and Fertilizer
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• v.43 no.6
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• pp.782-788
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• 2010

Detail management standard on soil conditions in 'Kyoho' grapes were not yet made. Therefore, this study was carried out to investigate the optimum soil environmental conditions on production of high fruit quality in 'Kyoho' grapes. We established using correlation between fruit quality and soil condition. These results were used to develop soil management guideline with promoting efficiency and minuteness in grape vineyard. Soil conditions were analyzed at total 80 vineyards in major grape producing areas such as Ansung, and Cheonan (40 orchards an area). The soil environmental factors affected fruit weight were soil pH of 36.6%, cultivation layer depth of 23.3%, and cation of 17.8%. The soil condition factors affected sugar content were soil hardness of 24.4%, cation of 24.1% and organic matter content of 22.1%. Cultivation layer depth, soil texture, and phosphate content were low as relative contribution. Coloring was involved with organic matter content, CEC (cation exchange capacity), and saturated hydraulic conductivity. while soil pH, cultivation layer depth, and phosphate content showed low contribution. Finally, relative contribution on fruit quality related with sugar content, fruit weight, and coloring were soil hardness of 28.0%, organic matter content of 25.0%, soil pH of 12.9%.

• Journal of Korean Society of Forest Science
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• v.100 no.3
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• pp.397-401
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• 2011

This study was conducted to clarify the breeding ecology of tits Parus spp. used artificial nest boxes in a deciduous forest at the Ansung Campus, Chung-Ang University from March through July, 2006 to 2010. Varied tit Parus varius, marsh tit P. palustris and great tit P. major bred in artificial nest boxes during our study period. There were no differences in number of breeding bird pairs among different entrance diameters of artificial nest boxes. The number of breeding pairs of great tits was the most highest among tits and that of varied tits was the least. Great tits mainly used 40 mm and 35 mm artificial nest box entrance diameter and marsh tits preferred 30 mm entrance diameter. In three tits species, there were differences in first egg date, clutch size, brood size, egg incubation period, nestling care period and breeding success among study years. It is needed the study on long-term ecological research about breeding ecology of tits related with habitat conditions.

• Journal of Nutrition and Health
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• v.55 no.2
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• pp.309-320
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• 2022

Purpose: This study aimed to investigate the association between steamed food intake and risk of metabolic syndrome (MetS) in Korean females. Methods: Using Ansan/Ansung data of Korean Genome and Epidemiology Study, general characteristics, nutritional intake and biochemical and anthropometric markers of a total of 4,056 females aged 40 to 69 years were analyzed. MetS was defined following National Cholesterol Education Program Adult Treatment Panel III with some minor modifications. Logistic regression models were established to present the association between steamed food intake and the risk of MetS. Levels of food and nutrient intake by the frequency of steamed food intake and MetS phenotype were analyzed using general linear models. Results: A total of 38.4% of females had MetS. Among them, 24.9% of females with MetS had steamed food more than 1-3 times per week, which reduced the risk for MetS by about 25% (95% confidence interval [CI], 0.650-0.865). However, such association was not evident when various lifestyle factors were considered in statistical models. In rural residents, the benefit of having more steamed food was observed (adjusted odds ratio: 0.747; 95% CI, 0.583-0.958). The frequency of steamed food intake was associated with various food and nutritional intakes. However, trends in those did not differ by MetS phenotype. Conclusion: Having steamed food more than 1-3 times per week may reduce the risk of MetS compared to those who had less steamed food in Korean females. This protective effect of steamed food intake may differ by lifestyle and environmental factors. Although a clear difference in food and nutritional intake was not observed in this study, steaming could be an effective cooking method for a healthy diet for disease prevention and management.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.42 no.6
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• pp.814-820
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• 1997

This study was conducted to establish standard fertilization rates for the cultivation of Korean valerian(Valeriana fauriei var. dasycarpa Hara) which is useful for medicinal and aromatic resources. Nitrogen, phosphate and potassium were treated with four application levels, 0, 6, 9, 12kg per 10a, and the growth characteristics, root yield and essential oil compositions of valerian were measured. The growth and root yield of valerian were the highest in the rate of 9kg per 10a for nitrogen, phosphate and potassium, respectively. Nitrogen had the most powerful effective followed by potassium and phosphate. The contents and compositions of essential oil also varied with the amount of fertilization. The contents of the essential oil was the highest in the application level of 9kg per 10a for nitrogen, phosphate and potassium, respectively. The essential oil compositions were affected by the fertilization rate.