• Asian Journal of Turfgrass Science
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• v.6 no.1
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• pp.1-10
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• 1992

This experiment was carried out to investigate the effect of mixing ratio of soil amending materials such as peat. perlite, active carbon, and zeolite on the growth and quality of creeping bentgrass (Agrostis pa1ustris var. Penncross). The results of this experiment were surnrnarized as follows; 1.Nitrogen content of clippings was increased by the treatment of peat and active carbon. hut the other phosphorus, potassium, calcium and magnesium content were increased in addition of,5% to 10% of peat, and 2.5% to 5% of active carbon. 10% of perlite. and 4% of zeolite 2.Fast growth and good quality of bentgrass were showed at the addition of 10% peat. l0% perlite.2.5~% active carbon, and 4% zeolite But over treatment of peat and active carbon induced inhi-bition of root growth and occurrence of disease.

• Asian Journal of Turfgrass Science
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• v.12 no.4
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• pp.189-194
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• 1998

The effect of proline, glutamine, aspartic acid and their combinations on callus induction and embriogenic callus formation from 3 creeping bentgrass (Agrostis palustris) cv. Regent, Mariner, Cato and 1 colonial bentgrass (Agrostis tenuis) cv. Tiger was estimated in both light and dark condition. The addition of amino acids to the growth medium did not have a significant stimulatory effect on the induction of embryogenic callus, instead, they were inhibitory, particularly at higher concentration (40 mM). But supplement of amino acids at lower concentrations (5 or 10mM) to basal medium was beneficial in inhibiting the formation of hairy outgrowth on the surface of embryogenic callus.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.29 no.11 s.242
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• pp.1439-1444
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• 2005

A two-dimensional boundary element method was used for the scattering analysis of side-drilled hole(SDH). The far-field scattering amplitude was calculated for shear vertical(SV) wave, and their frequency and time-domain results were presented. The time-domain scattering amplitude showed the directly reflected wave from the SDH leading edge as well as the creeping wave. In an immersion, pulse-echo testing, two measurement models were introduced to predict the response from SDHs. The 2-D boundary element scattering amplitude was converted to the 3-D amplitude to be used in the measurement model. The receiver voltage was calculated fer SV wave incidence at 45$^{\circ}C$ on the 1 m diameter SDH, and the result was compared with experiment.

• Proceedings of the Korean Institute of IIIuminating and Electrical Installation Engineers Conference
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• 2008.10a
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• pp.253-255
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• 2008

This paper gives a basic data of the surface discharge characteristics for epoxy resin in Dry-Air. Used electrodes are needle to plane, sphere to plane and KS M3015 electrodes. With the changing electrodes in same condition, we can obtain different creeping lengthes, breakdown voltages and dielectric strengths, respectively. Dielectric strengths of Needle to plane electrodes are more higher than the others. Breakdown voltage and dielectric strength increase as the thickness of epoxy resin and creeping strength increase.

• 전기의세계
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• v.14 no.2
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• pp.8-13
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• 1965

It is expected that the impurities contained in a solid state insulation material will affect a considerable influence on its break-down voltage, dielectric loss, and insulation resistance. In this thesis, as a preliminary experimental research for the investigation described above, the effect of metalic barrier between the electrodes on the creepin flash over discharge voltage along the surface of a solid insulation material has been investigated, and got some interesting results. It was found that generaly the flash over voltage rises when a metalic barrier is located between the electrodes. The results of this investigation will be taken into account as an important components on the insulation design to prevent the creeping flash over discharge in insulators, bushings, and so on.

• Proceedings of the Turfgrass Society of Korea Conference
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• 2011.02a
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• pp.65-69
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• 2011

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.513.1-513.1
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• 2006

• Asian Journal of Turfgrass Science
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• v.24 no.2
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• pp.125-130
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• 2010

Dollar spot and brown patch disease are the most economically important disease for highly maintained turfgrass area such as golf courses. Previous researches indicated that various natural fertilizers are good nitrogen (N) sources and they may lead to turf disease suppression because disease suppression by natural N sources may be due to microbial activity increased. Increased microbial activities in soil reduce the activity of plant pathogen. The objective of this study was to evaluate efficacy of various N sources to suppress dollar spot and brown patch on creeping bentgrass. The seven N sources and fungicide combinations were investigated for turf disease suppression. $Emerald^{TM}$ and $ProStar^{TM}$ were applied for the applications of fungicide combination. No differences were found on turf quality among N source treatments. However, there was significant difference on turf quality between fungicide combination and fungicide combination plus urea. Overall, N source had no significant effects on suppression of dollar spot and brown patch. Although there were a few differences among N source treatments, fungicide treatments were needed for turf disease suppression for highly maintained turfgrass area such as golf courses.

• Asian Journal of Turfgrass Science
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• v.26 no.2
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• pp.102-109
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• 2012

Commercial formulation of fungicides was studied in the golf course for evaluation against Typhula incarnata causal agents of gray snow mold. Efficacies of fungicides application, fungicide mixture, fungicides applied method (irrigation and spray) and fungicides applied time (early fall and late fall) were evaluated for their influence on the chemical control of gray snow mold of turfgrass during the winter season in Yongpyeong golf course, Korea. Unsprayed control has significantly more disease severity than three fungicides (azoxystrobin, propiconazole, and tebuconazole) were applied to field plots. Effect of three fungicides was over 80% with control value for controlling gray snow mold on Kentucky bluegrass and creeping bentgrass species. Effect of fungicide mixture with different family groups had an over 93% control value of gray snow mold on Kentucky bluegrass species. It was not significantly difference in fungicidal effect according to applied method (irrigation and spray) with azoxystrobin on Kentucky bluegrass and creeping bentrasss species. Effect of fungicides applied time was a significantly difference on disease control by tebconazole early fall spray.

• Journal of Korean Society of Forest Science
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• v.94 no.3 s.160
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• pp.129-134
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• 2005

Ths study was carried out to understand the geo-topographical characteristics of the landslide area (1.5 ha) in Maeri, Sangdong-myeon, Gimhaesi, Gyeongsangnam-do. The bedrock of the landslide area was diollites and the area in and around the upper slope with the scattered talus was composed of Masanam originated from Igneous rocks. The landslide occurred in 19th of April, 2004 and the amount of rainfall for 3 days before the landslide was 74mm. The landslide by land creeping in this area was mainly attributed to geo-topographical characteristics such as well developed colluvial and/or weathered soils, and land cutting in lower slope, although the landslide could be affected by the rainfall. The type of the landslide can be classified into the land creeping by concave colluvial soils.