• Journal of Bio-Environment Control
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• v.16 no.3
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• pp.205-209
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• 2007

This experiment was conducted to investigate the growth of plug seedlings and yield of tomato affected by the concentration of triazole and the treatment time. The length and leaf area of tomato seed-lings were reduced by the application of triazole compared to control. Growth reduction of seedlings was greater by earlier application and higher concentration of triazole. The growth of tomato treated with hexaconazole were similar with control 4 weeks after sowing. The triazole treatment lowered the height of the first fruit set compared to control. However, triazole treatment did not affect the number of fruits and yield.

• Journal of Digital Convergence
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• v.14 no.11
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• pp.27-35
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• 2016

The study was conducted to identify related risk factor of elderly's suicidal ideation. This study used a cross-sectional design with secondary analysis of the $6^{th}$ 2013 Korea National Health and Nutrition Examination Survey (KNHANES). Data for 1,201 elderlies who aged over 65 years old from the KNHANES were included. Suicidal ideation, general characteristics, physical health, psychological health, EuroQoL, and health behavior were measured. Chi-square test, t-test, and multiple logistic regression were used to analyze this data through the SPSS win 22.0 program. In the results, 7.7% of the elderly had suicidal ideation. The odds ratios of suicidal ideation were significantly higher among those with restriction of activity (OR=1.31, CI=1.40~3.82), those with depression (OR=4.44, CI=1.66~7.40), and those with high levels of stress (OR=9.24, CI=3.48~24.5). Therefore, the activity level, depression level, and stress level need to be regularly assessed in order to prevent suicidal ideation among the elderly.

• Geophysics and Geophysical Exploration
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• v.8 no.1
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• pp.34-40
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• 2005

We have used the microtremor method, with arrays of up to 96 m diameter, to carry out non-invasive estimation of shear-wave velocity profiles to a depth of 30 to 50 m in unconsolidated Quaternary Yarra Delta sediments. Two silt units (Coode Island Silt, and Fishermans Bend Silt) dominate our interpretation; the method yields shear velocities for these units with precision of $5\%$, and differentiates between the former, softer unit ($V_s$=130 m/sec) and the latter, firmer unit ($V_s$=235 m/sec). Below these silts, the method resolves a firm unit correlating with known gravels ($V_s$ 500 to 650 m/sec). Using surface traverses with the single-station H/V spectral ratio method, we show that the variation in thickness of the softer silt can be mapped rapidly but only qualitatively. The complexity of the geological section requires that array methods be used when quantitative shear-wave velocity profiles are desired.

• Journal of Digital Convergence
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• v.19 no.12
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• pp.369-376
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• 2021

The purpose of this study is to identify the effect of depression on chewing problems and the importance of oral aids through a point-in-time analysis. The data are the 4th(2008, 2^nd year) and the 7th(2018, 3^rd year) of the National Health and Nutrition Survey. The analysis method was frequency analysis and regression analysis using the SPSS/WIN 24.0 program. Studies have shown that depression has affected chewing problems(p<.001). Chronic diseases and the use of oral aids affected the chewing problem. The prevalence and treatment of depression affected the chewing problems(p<.001). In addition, private health insurance coverage increased in 2018 compared to 2008. In the future, the comparative studies considering various subjects and chronic diseases, the educational methods for the use of oral aids are needed.

• Journal of the Microelectronics and Packaging Society
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• v.28 no.4
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• pp.79-83
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• 2021

In this study, hollow silica microspheres (HSM) of various sizes formed according to the concentration of surfactants using water glass as a precursor, which is advantageous for commercialization due to its lower unit cost compared to conventional silicon alkoxide (tetraethyl orthosilicate, TEOS) was synthesized. The physical properties of the silica hollow microspheres according to the concentration of surfactant were analyzed using Fourier transform infrared, contact angle measurement, Brunauer-Emmett-Teller and Barrett-Joyner-Halenda analyzers and field emission scanning electron microscopy. When porous water glass-based hollow silica spheres were prepared by adding a surfactant at an appropriate concentration, it was confirmed that excellent hollow silica spheres were formed with a specific surface area of 169 m²/g, an average particle size of 25.3 ㎛, and a standard deviation of 6.25.

• Polymer(Korea)
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• v.28 no.2
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• pp.154-161
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• 2004

Modified poly(4-vinylpyridine) was obtained by partial quarternization of nitrogen atoms in pyridine rings of poly(4-vinylpyridine) with methyl group. By means of laser light scattering and fluorescence, it was found that this modified polymer chains were aggregated in the aqueous solution and its structure was core-shell type. The hydrophobic parts of the chains were densely condensed in core part and the hydrophilic part of quarternized amino with positive charge formed the shell part. In the mixed system of modified poly(4-vinylpyridine) and anionic surfactant, sodium dodecyl sulfate, it was observed that a critical aggregation concentration existed and that this critical concentration was suddenly decreased above 0.1 M NaCl. The size change of aggregates was also investigated by dynamic light scattering while sodium dodecyl sulfate was added into polymer solution upto the critical aggregation concentration.

• Economic and Environmental Geology
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• v.52 no.3
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• pp.251-258
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• 2019

During the detailed geological survey around the southern Yangsan Fault, we newly found a Quaternary fault outcrop, which cuts unconsolidated sediments. The fault named the Sinwoo site, located in the Sinwoo pasture, Miho-ri, Duseo-myeon, Ulsan metropolitan city, is the first discovered Quaternary fault near the western part of the south Yangsan Fault. In this study, we provide information on characteristics of fault geometry and unconsolidated sediment at Sinwoo site based on the analysis data of topography, drainage, and lineament around the study site. The fault site is situated at pediment slope, but fan-shaped middle terrace, as well as thick sediment exposed at low terrace, indicates that the unconsolidated sediments have been deposited in the alluvial fan environment. The drainage develops to the third-order drainage system, and the first and the second drainage system meet at right angles to each other and form a radial drainage pattern. In addition, the NE-SW direction lineaments can be identified on the basis of the curvature of the river and the step of the topographic relief, running over the Sinwoo site. The fault of $N30-35^{\circ}E/79-82^{\circ}SE$ shows ~ 5.8 m apparent vertical offset and dominantly reverse-slip sense based on slickenline, rotation of pebbles, and drag folding at footwall. However, some discontinuous sediments observed in the footwall are interpreted as fissure-filling materials due to the strike-slip movement. Now, we are under multidisciplinary investigations of additional field survey and age dating in order to determine the evolution of Sinwoo site fault during the Quaternary.

• Korean Journal of Weed Science
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• v.5 no.2
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• pp.175-186
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• 1985

Research situation and recent research activities of the RDA of Korea were reviewed and summarized for rice nurserybed. Sixty five percent of total 784 weed research items were carried out as rice research while only 6 percent was belonged to nurserybed within rice research. The floristic composition based on the degree of dominance significantly affected by herbicide properties, type of nurserybed and seeding itself. Herbicidal phytotoxicity of currently used several herbicides was greatly dependent upon the covering, absorption, germination, and irrigation regimes. The new safening agent "CGA 123 407" (4,6-dichloro-2-phenyl-pyrimidine) permited the safe application of pretilachlor (2-chloro-2',6-diethyl-N-(2-propoxyethyl) acetanilide) as a pre-emergence herbicide without reducing herbicidal efficacy. Several new herbicides, pyrazolate (4-(2,4-dichlorobenzoyl)-1,3-dimethylpyrazol-5-yl-p-toluenesulphonate), SL-49 (1,3-dimethyl-4-(2,4-dichlorobenzoyl)-5-phenacyloxy-pyrazole) MY-93 (S(1-methyl-1-phenethyl)-piperidine-1-carbathioate) and DPX-84 ((methyl 2- ((4,6-dimethoxypyrimidin-2-yl) amino-carbonyl) aminosulfonylmethyl)) benzolate)) performed satisfactorily in terms of safety and herbicidal efficacy for both surface covered and surface pressed nurserybed after herbicide application and thus expected very significant contributions not only for all kind of nurserybeds but also for direct seeding.

• Journal of the Korean Wood Science and Technology
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• v.28 no.3
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• pp.70-77
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• 2000

Among four compounds such as oxyresveratrol, resveratrol, morin and afzelechin isolated from the heartwood of Morns bombycis, oxyresveratrol and resveratrol which belong to stilbenoid indicated high antioxidative and antimicrobial activity, respectively. Based on this result, this experiment was carried out to elucidate the relationship between biological activities of stilbenoids and their chemical structures using two isolated and six synthesized ones prepared by Wittig reaction. Antimicrobial activity of 3,5-dihydroxystilbene(pinosylvin) devoid of hydroxyl group of B-ring was the best among the tested stilbenoids. Antimicrobial activities of the stilbenoids showed negative dependency on the number of hydroxyl groups of B-ring, that is, the fewer number of hydroxyl groups of B-ring, the higher antimicrobial activity. On the other hand, antioxidative activities of the stilbenoids indicated a positive relationship with the number of hydroxyl groups of B-ring. In tetrahydroxystilbenoids, antioxidative activities of the compounds possessing ortho-diphenol structure, 2',3,3',5- and 3,3',4',5-tetrahydroxystilbene, were superior to the others. As a result, it was concluded that resveratrol and oxyresveratrol isolated from the heartwood of M. bombycis had antimicrobial and high antioxidative activities, and these activities of stilbenoids were also dependent on the number and position of hydroxyl groups of B-ring.

• Korean Journal of Weed Science
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• v.4 no.2
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• pp.179-187
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• 1984

This experiment was carried out to clarify the effect of herbicide chlormethoxynil 7G, CNP 9G and butachlor 3.5/pyrazolate 6G on weed control and seedling growth in rice seedbed. Different quantities of the herbicides were applied as soil incorporation or surface broadcasting. At earlier sowing annual grasses such as Echinochlva spp. and Alopecurus spp. were dominated, but Cyperus spp. were dominated at later sowing. Weed suppression by herbicides was greater in soil incorporation than in broadcasting and chlormethoxynil 7G and CNP 9G application (30kg/ha) showed about 70% weed control, while butachlor 3.5/pyrazolate 6G (10-20kg/ha) showed 90 to 100% weed control. At lower rate of butachlor 3.5/pyrazolate 6G (10kg/ha) emergence ratio, healthy seedling ratio and relative growth rate of rice were higher, and phytotoxicity was lower than in the others.