• Korean Journal of Agricultural and Forest Meteorology
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• v.3 no.2
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• pp.75-80
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• 2001

This study was conducted to identify the optimum proper nitrogen (N) application rate for tillering in ridge direct seeding on dry paddy of rice culture. During 1998, a series of experiments was carried out at paddy field (Chonbuk series) of the National Honam Agricultural Experiment Station, RDA using Dongjinbyeo. Leaf area index and top dry weight increased with higher N levels, especially in the 100 kg/ha seeding rate compared with the 60 kg/ha seeding rate. N use efficiency increased at increased by 50~75% of the N topdressing rate at tillering. Heading date, ripened grain rate, and 1,000-grain weight of brown rice did not vary among the rate of topdressing for tillering and seeding rates. The highest grain number per unit area was at the level of increased by 75% in N topdressing at tillering stage. Milled rice yield increased 5% at the 60 kg/ha seeding rate and increased 16~17% at the 100 kg/ha seeding rate at increased by 50~75% of topdressing N compared with 48 kg/ha topdressed N of 60 kg/ha seeding rate.

• Journal of the Korea Fashion and Costume Design Association
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• v.21 no.4
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• pp.213-220
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• 2019

The dry cleaning effect related to the type of soil and fiber was analyzed using silicone and alcohol-based solvents(ethyl alcohol, isopropyl alcohol, acetone) that are relatively safe for the human body and environment to improve the detergency of hydrophilic soils in dry cleaning system. Based on this analysis, an effective dry cleaning method to be carried out for improving the detergency according to the type of hydrophilic soils. After dry cleaning was performed using 20 types of artificial soiled fabrics consisting of 7 types of fibers and 4 types of hydrophilic soils, the detergency was measured and the results were compared and analyzed by solvents and fiber types. The results are presented as follows; first, the detergency of hydrophilic soils using silicone solvents showed a low rate of detergency. In particular, the tannin soil showed a lower level of detergency compared to the protein soil. Second, the detergency of hydrophilic soils using silicon solvents with dry soap differed in some detergency according to the soil and fiber types. Especially, the detergency of curry soil on cotton fabric showed significant improvement. Third, the protein soil was not removed from dry cleaning using alcohol-based solvents, but the effect of dry cleaning of curry soil on both cotton and polyester fabric was substantially improved. As a result, the elimination of blood soil is more effective in silicon solvents than in alcohol-based solvents. The removal of tannin soils may improve detergency by adding dry soap to silicon solvents or by using alcohol-based solvents as alternative solvents. The use of alternative solvents such as silicon and alcohol solvents can contribute to the environmental improvement of the dry cleaning industry, which uses petroleum-based solvents. It is also expected to provide consumers with the opportunity to choose eco-friendly and efficient dry cleaning methods.

• Journal of the Korean Society of Clothing and Textiles
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• v.11 no.1
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• pp.79-85
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• 1987

The purpose of this study was to help the consumer about the care of nonwoven fabrics by investigation of the properties such as launderability. shrinkage, color fastness and strenth. Materials used were two types, soft and stiff, of commercial nonwoven fabrics. Deter-gents used were neutral detergents, synthetic detergents and dry cleaning solutions(perch-toro-ethylene) The results of this study were summerized as follows; 1. Laundering of nonwoven fabrics in low temperature is more ideal as morphological changes by laundering in high temperature were more prominent than that in low temperature. 2. Ironing of nonwoven fabrics wants more attention on environmental temperature as the rate of shrinkage in high temperature was higher than that in low temperature. Neutral detergents are more desirable as the rate of shrinkage of nonwoven fabrics by laundering with synthetic detergents was more prominent than that with neutral deter-gents. The rate of shringkage of nonwoven fabrics was not affected by dry cleanining. 3. Special care is wanted in order to prevent color transfer from non woven fabrics to polyester or wool during dry cleaning or laundering as the color fastness test show that color changes of nonwoven fabrics were not affected, but that color stain was increased on polyester or wool. 4. The strength was affected by composition of fibers and types of nonwoven fabrics, soft or stiff.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.49 no.4
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• pp.203-209
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• 2000

This paper proposes the improvement of the etch rate of GaN using a magnetized inductively coupled $CH_4/H_2/Ar$plasma. The gradient magnetic field with the axial direction is investigated using Gauss-meter and the ion current density is measured using double Langmuir probe. The applied magnetic field changes the ion current density profile in the radial direction, resulting in producing the higher density in the outer region than in the center. GaN dry etching process is carried out based on the measurements of the ion current density. The each rate of 2000 /min is achieved with $CH_4/H_2/Ar$ chemistries at 800 W input power, 250W rf bias power, 10 mTorr pressure and 100 gauss magnetic field.

• Journal of the Korean Ceramic Society
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• v.39 no.6
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• pp.570-575
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• 2002

The present tendency of electrical and electronics is concentrated on MEMS devices for advantage of miniaturization, intergration, low electric power and low cost. Therefore it is essential that high aspect ratio and high etch rate by HDP technology development, so that silicon deep trench etching reactions was studied by ICP equipment. Deep trench etching of silicon was investigated as function of platen power, etch step time of etch/passivation cycle time and SF$\_$6/:C$_4$F$\_$8/ flow rate. Their effects on etch profile, scallops, etch rate, uniformity and selectivity were also studied.

• Asian-Australasian Journal of Animal Sciences
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• v.4 no.4
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• pp.369-375
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• 1991

A series of in vitro incubation studies with washed rumen bacteria were conducted to determine the influence of incubation time and concentrations of peptides, alanine, ammonia nitrogen and carbohydrate on the rate of peptide disappearance and on bacterial growth. Disappearance rate of tri-alanine (ala3) under various conditions was between 30.6 and $58.2mg\;hr^-$ per gram bacterial dry matter. Ala3 was removed from the incubation medium in an almost linear fashion as incubation time and ala3 concentration was increased. Washed rumen bacteria utilized ala3 faster than di-l-alanine (ala2) at all concentrations. Adding 9mM carbohydrate significantly increased ala3 disappearance, but level of ammonia nitrogen had no influence on ala3 disappearance. The presence of alanine in the medium significantly lowered ala3 utilization by rumen bacteria. Bacterial dry matter and nitrogen growth yield were not influenced by alanine and peptides when incubation medium already contained a sufficient level of ammonia nitrogen. Increased ammonia nitrogen in the presence of ala3 did not stimulate bacterial growth. Carbohydrate significantly increased bacterial dry matter and nitrogen growth as expected. Results indicate that the rate of peptide utilization by rumen bacteria may be altered by type and concentration of peptides, and energy supply, and this may be mediated through changes in numbers and type of bacteria.

• Journal of ILASS-Korea
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• v.14 no.3
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• pp.131-138
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• 2009

In the present study, spread-recoil behavior of a drop of shear-thinning liquid (xanthan solution) on a dry wall (polished stainless-steel plate) was examined and compared with that of Newtonian liquid (glycerin solution). Nine different kinds of xanthan and glycerin solutions were tested, including three pairs of xanthan and glycerin solutions, each having the same viscosity in low shear rate region ($10^{-2}-10^0\;l/s$). The drop behavior was visualized and recorded using a CCD camera. The maximum diameter and the spreading velocity of the xanthan drops turned out to be significantly larger and the time to reach their final shape was much shorter compared to the cases with the glycerin solutions, due to the smaller viscous dissipation resulted from lower viscosity in the higher shear rate region (>$10^0\;l/s$). As a result, the maximum diameters were measured to be larger than the predicted values based on the model proposed for Newtonian liquids, and the deviation was more pronounced with the solution with the larger viscosity variation. Consequently, viscosity variation with the shear rate was found to be a dominant factor governing the spread-recoil behavior of shear-thinning drops.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.1
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• pp.110-115
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• 2004

This experiment was conducted to investigate the effect of light intensities on the growth responses, carbohydrate contents and the characteristics of leaf gas exchange in Miscanthus sinensis and Pennisetum purpurascens. The plant height and leaf length were increased to about 30% in the sun. However, those were reduced severely in the shade, and leaf necrosis was also observed. The representative growth index and the dry weight of 2 species were 50% higher than shade and the rate was reduced according to the decrease of light intensities. Total carbohydrate contents showed very similar changes to that of dry weight. However, any notable influences were observed at above the light intensities of 250~500${\mu}mol{\cdot}m^{-2}{\cdot}s^{-1}$ in the half shade. The size of spikes and the earliest spiking appeared in the sun and the spike color was decolorized as decreased in light intensities, irrespective of species. Photosynthetic rate of 2 species was 2 times higher in the sun than those in the shade, and it showed the typical photoresponses of sun plant. Stomatal conductances and intercelluar $CO_2$ concetration showed similar changes to that of photosynthetic rate. On the contrary, vapor pressure deficit was increased more in the shade than in the sun.

• The Transactions of the Korean Institute of Electrical Engineers C
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• v.48 no.9
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• pp.616-621
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• 1999

A planar inductively coupled $CH_4/H_2/Ar$plasma was used to investigate dry etch characteristics of GaN as a function of input power, RF bias power, and etch gas composition. Etch rate of GaN increased with input power up to 600 W and was saturated at the higher power. Also, the etch rates increased with increasing RF bias power, composition of $CH_4$ and Ar gas. We achieved the maximum etch rate of $930{\AA}$/min at the input power 400 W, RF bias power 250 W, and operational pressure 10 mTorr. This paper shows that smooth etched surface having roughness less than 1 nm in rms can be obtained by using planar inductively coupled plasma with $CH_4/H_2/Ar$ gas chemistry.

• Bulletin of the Korean Chemical Society
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• v.23 no.8
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• pp.1149-1153
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• 2002

CH4/CO2 dry reforming was carried out to make syn gas on the Ni/Al2O3 catalysts calcined at different temperatures. The Ni/Al2O3 (850 $^{\circ}C)$ catalyst gave good activity and stability w hereas the Ni/Al2O3 $(450^{\circ}C)$ catalyst showed lower activity and stability. The NiO/Al2O3 catalyst calcined at $850^{\circ}C$ for 16 h (Ni/Al2O3 $(850^{\circ}C))$ formed the spinel structure of nickel aluminate, which was confirmed by TPR. The carbon formation rate on the Ni/Al2O3 $(850^{\circ}C)$ catalyst was very low till 20 h, and then steeply increased with reaction time without decreasing the activity for CH4 reforming. The Ni/Al2O3 $(450^{\circ}C)$ catalyst showed high carbon formation rate at the initial reaction time and then, the rate nearly stopped with continuous decreasing the activity for CH4 reforming. Even though the amount of carbon deposition on the Ni/Al2O3 $(850^{\circ}C)$ catalyst was higher than that on the Ni/Al2O3 $(450^{\circ}C)$ catalyst, the activity for CH4ing was also high, which could be attributed to the different type of the carbon formed on the catalyst surface.