• Journal of dental hygiene science
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• v.13 no.4
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• pp.461-470
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• 2013

In order to examine the anticariogenic effect after fluoride varnish was applied to sound enamel and artificial caries enamel, anterior teeth of healthy cattle were used and divided into four groups such as group 1 (sound enamel), group 2 (application of fluoride varnish to sound enamel), group 3 (artificial caries enamel) and group 4 (application of fluoride varnish to artificial caries enamel). Remineralization on the surface of enamel and changes of crystalline structure after demineralization were observed by using a field emission scanning electron microscope (FE-SEM). Quantitative analysis of Ca and P was measured by using the energy dispersive X-ray spectrophotometer (EDS). The following conclusions were obtained: 1)Surface pattern of enamel was the roughest in group 3 due to the defects caused by porosity and microcracks. Group 4, group 1 and group 2 were followed in order; 2) It was found that pattern of crystalline structures in a group of application of fluoride varnish and a group of no application showed bigger change in artificial caries enamel than that in sound enamel. In other words, groups 4 and 1 showed a similar pattern; 3) The contents of Ca and P were higher in groups of application of fluoride varnish (group 2 and group 4) than in groups of no application of fluoride varnish (group 1 and group 3). Taken results of this study together, in the case of application of fluoride varnish, crystalline structure was changed by remineralization even in the sound enamel. In particular, porous structures showed a smooth and uniform pattern due to the recalcification in the artificial caries enamel. In addition, according to results of EDS analysis, the contents of Ca and P were increased and it had great anticariogenic effects which inhibit decalcification of sound enamel and artificial caries enamel.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.26 no.4
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• pp.279-286
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• 1981

This study was conducted to find out the effect of wollastonite application in degraded saline soil condition on the growth of japonica rice variety. The variety, Palgweng was tested with 4 levels of wollastonite (200, 400, 600 and 400/200 kg/l0a) and two nitrogen levels (12 and 16 kg/l0a). The effect of wollastonite was higher in 16 than 12 kg of nitrogen application. The wollastonite application reduced rice leaf blast and dead left at lower nodal position, and increased percentage of effective tillers, percentage of ripened grains and 1, 000 grain weight. The SiO$_2$ content of upper leaf was higher than lower leaf in 200 kg of wollastonite application, but there was no difference under high wollastonite application (400 kg/l0a). Highly significant positive correlationships were obtained between SiO_2 content of plant at heading and percentage of ripened grains, (r=0.613) and SiO_2 content of flag leaf and percentage of ripened grains (r=0.407). Wollastonite application did not affect the development and degeneration of primary and secondary rachis branches of panicles, but it increased the number of spikelets. The highest grain yield was obtained with 16 kg of nitrogen and 600 kg of wollastonite.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.35 no.3
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• pp.218-223
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• 1990

This experiment was carried out to obtain basic information on the lodging characteristics and yield components of rice plants by new anti-lodging reagent 'KIM-112' (3%, Wp) application at 30 days before heading (DBH) to 5 DBH under two dosage levels (lg 2g, a. i. /10a) at the Yeongnam Crop Experiment Station in 1989. Culm length was shortened by 10-17% at 1g, a. i. /10a and by 16-23% at 2g of KIM -112 applications. The shortening effect of internode was different by dosages and application times: 2g treatment was greater effect than 19 and early application resulted in shortening of lower internode while this was upper internode at the late application. There were positive correlation between culm length and lodging index, the 1st and the 4th internode lengths had on important effect to lodging index. Thickness of culm wall, culm diameter and weight of basal part of culm were not affected by KIM-112 application. However anti-lodging characters improved by increasing the breaking weight and by decreasing the moment. Lodging index was related to breaking weight, moment and weight of panicle. Heading date by KIM-112 application was delayed one to four days and number of grains per panicle was decreased by shortened panicle length as compared with untreated control, but yield capacity was high a little because of improvement ripening ratio by no lodging.

• Journal of Power Electronics
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• v.5 no.1
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• pp.62-66
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• 2005

A simple fault correction method for rotor position detection of a brushless DC(BLDC) motor with trapezoidal back EMF(electromotive force) using a Hall effect latch unit is presented. The reason why the Hall effect latch unit does not operate properly during the startup of a BLDC motor is thoroughly explained. To solve this problem, a simple code change method and its hardware implementation issues are proposed and discussed.

• Journal of applied mathematics & informatics
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• v.16 no.1_2
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• pp.323-336
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• 2004

We consider the application of complex variable method to elastic problem and investigate the nonlinear effect of finite torsion of a compressible elastic composite layer. We obtain that as a result of finite deformation approach, a tube subjected to torsion decreases in radius giving rise to a “hold effect”.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1993.04a
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• pp.437-437
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• 1993

• Journal of the Korean Professional Engineers Association
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• v.32 no.1
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• pp.18-22
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• 1999

• Proceedings of the Korea Society of Design Studies Conference
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• 1995.11a
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• pp.84-85
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• 1995

• Magazine of the Korea Concrete Institute
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• v.13 no.4
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• pp.62-67
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• 2001

• Restorative Dentistry and Endodontics
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• v.38 no.3
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• pp.186-186
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• 2013