• Journal of the Korean Mathematical Society
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• v.48 no.2
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• pp.431-447
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• 2011

We investigate the asymptotic behavior of positive solutions to the elliptic equation (0.1) ${\Delta}u+|x|^{l_1}u^p+|x|^{l_2}u^q=0$ in $\mathbb{R}^n$. We obtain a conclusion that, for n $\geq$ 3, -2 < $l_2$ < $l_1$ $\leq$ 0 and q > p > 1, any positive radial solution to (0.1) has the following properties: $lim_{r{\rightarrow}{\infty}}r^{\frac{2+l_1}{p-1}}\;u$ and $lim_{r{\rightarrow}0}r^{\frac{2+l_2}{q-1}}\;u$ always exist if $\frac{n+1_1}{n-2}$ < p < q, $p\;{\neq}\;\frac{n+2+2l_1}{n-2}$, $q\;{\neq}\;\frac{n+2+2l_2}{n-2}$. In addition, we prove that the singular positive solution of (0.1) is unique under some conditions.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.23 no.1
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• pp.37-43
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• 2013

Conductivity of LSGMC materials were affected by secondary phase segregation, composition and synthetic route. $La_{0.8}Sr_{0.2}Ga_{0.8}Mg_{0.1}Co_{0.1}O_{3-{\delta}}$ (LSGMC) powders were prepared using the glycine nitrate process to produce high surface area and compositionally homogeneous powders. The powders were synthesized with different 0.5, 1, 1.5, 2, 2.5 of glycine/cation molar ratios. A single perovskite phase from the synthesized powders was characterized with X-ray diffraction patterns. The obtained sintered pellets showed the dense grain microstructure. In case of 1.5 molar ratio, its density was higher than the others. The electrical conductivity measured at $800^{\circ}C$ was observed to be 0.131 $Scm^{-1}$. In addition, the linear thermal expansion behavior was indicated between $25^{\circ}C$ and $800^{\circ}C$.

• Journal of the Korean Electrochemical Society
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• v.16 no.3
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• pp.151-156
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• 2013

As the cathode material for li-ion battery, $LiNi_{0.5}Mn_{0.3}Co_{0.2}O_2$ were synthesized by supercritical hydrothermal method and calcined $850^{\circ}C$ and $900^{\circ}C$ for 10hrs in air. The effect of temperature in the heat treatment on the powder and its performance were studied of xray diffraction pattern, SEM-image, physical properties and electrochemical behaviors. As a result, calcined at $900^{\circ}C$ material particle size more increase than calcined at $850^{\circ}C$ material, especially shows excellent electrochemical performance with initial reversible specific capacity of 163.84 mAh/g (0.1C/2.0-4.3V), 186.87 mAh/g (0.1C/2.0-4.5V) and good capacity retention of 91.49% (0.2C/2.0-4.3V) and 90.36% (0.2C/2.0-4.5V) after 50th charge/discharge cycle.

• Proceedings of the KAIS Fall Conference
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• 2009.05a
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• pp.603-606
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• 2009

본 연구는 폐 병소의 경피적 흡인 생검을 시행하는데 있어 기흉 발생에 영향을 미치는 요인을 7가지로 나누어 분석하여, 국소적인 폐 병소를 보인 25~85세 사이의 104명의 환자를 대상으로, 병변의 위치, 병변의 크기, 병변의 깊이, 성별, 나이, 생검 시간, 생검 횟수로 나누어 기흉 발생과의 연관성을 연구하였다. 그 결과는 다음과 같다. 1. 위치에 따른 기흉 발생률은 우하엽에서 27.3%, 우상엽 24.3%, 좌하엽 15%, 좌상엽 12% 순으로 나타났으며, 병변의 크기에 따른 기흉 발생률은 0~2.0cm에서 24.0%, 2.1~4.0cm에서 18.2%, 4.1cm 이상에서 20.0%이었으며, 병변의 깊이에 따른 기흉 발생률은 0cm에서 6.7%, 0.1~2.0cm에서 24.2%, 2.1cm이상인 경우가 26.8%이며, 성별에 따른 기흉의 발생은 남성 21.7%, 여성 17.1%로 나타났으며, 나이에 따른 기흉 발생은 40세 이하가 25%, 41~50세가 11.7%, 51~60세가 14.3%, 61~70세가 24.1%, 70세 이상이 24.1%로 나타났고, 생검 시행 횟수에 따른 기흉 발생률은 4회 이상에서 28.6%, 2회 이하에서 20.5%, 3회에서 17.4%로 각각 나타났다. 이 모두는 통계적으로 유의한 차이는 없었다(P=0.484, 0.859, 0.088, 0.581, 0.758, 0.658). 2. 생검에 걸리는 시간에 따른 기흉 발생률은 0~10.0분에서 3.8%, 10.1~20.0분에서 24.2%, 21분 이상에서 40%로 시간이 오래 걸릴수록 기흉 발생률은 증가하였으며 통계적으로 유의한 차이가 있었다(P=0.005).

• Journal of the Korean Chemical Society
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• v.55 no.4
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• pp.626-632
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• 2011

Phoxim, which is one of veterinary drugs, is a well-known antiparasitic agent in wide use. In this paper, phoxim was extracted from cattle and pig tissue using solid-phase extraction (SPE) employing a silica cartridge with acetonitrile. Liquid chromatography/electrospray ionization-tandem mass spectrometry (LC/ESI-MS/MS) for the analysis of phoxim from animal tissue was presented. Phoxim was detected on a $C_{18}$ column ($2.1{\times}100\;mm$, $3.5\;{\mu}m$) using a mobile phase of 0.1% formic acid in water and acetonitrile. A linear correlation observed in the calibration curves for cattle (0.0048~2.0 mg/kg) and pig (0.0055~2.0 mg/kg) showed above $r^2$=0.995. Accuracy measured at concentrations ranging from 0.0048 to 0.2 mg/kg was the range of 68.2~106.9%. Limit of detection (LOD) and limit of quantitation (LOQ) were the range of 0.0014~0.0017 mg/kg and 0.0048~0.0055 mg/kg, respectively. The precision (RSD%) was below 11.2%.

• Journal of the Korean Electrochemical Society
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• v.13 no.4
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• pp.264-269
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• 2010

$LiNi_{0.5}Mn_{0.3}Co_{0.2}O_2$ active material was prepared by simple-combustion method and investigated as the cathode material for li-ion battery. The structural characterization was analyzed by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM), respectively. The XRD patterns of $LiNi_{0.5}Mn_{0.3}Co_{0.2}O_2$ sample was indicated a phase of layered hexagonal structure. The size of particles has not uniform diameters ranging from 100 to 300 nm. The electrochemical performance of the $LiNi_{0.5}Mn_{0.3}Co_{0.2}O_2$ was measured by Cyclic Voltammetry and galvanostatics. The $LiNi_{0.5}Mn_{0.3}Co_{0.2}O_2$ shows the discharge capacity of ~162 mAh/g in the range of 2.8 to 4.3 V at the first cycle.

• Journal of the Korean Electrochemical Society
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• v.16 no.4
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• pp.191-197
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• 2013

The one of the cathode material, $Li(Ni_{0.5}Co_{0.2}Mn_{0.3})O_2$, was synthesized by the precursor, $Ni_{0.5}Co_{0.2}Mn_{0.3}(OH)_2$, from the co-precipitation method and the morphologies of the primary particle of precursors were flake and needle-shape by controlling the precipitation parameters. Identical powder properties, such as particle size, tap density, chemical composition, were obtained by same process of lithiation and heat-treatment. The relation between electrochemical performances of $Li(Ni_{0.5}Co_{0.2}Mn_{0.3})O_2$ and the primary particle morphology of precursors was analyzed by SEM, XRD and EELS. In the $Li(Ni_{0.5}Co_{0.2}Mn_{0.3})O_2$ cathode from the needle-shape precursor, the primary particle size was smaller than that from flake-shape precursor and high Li concentration at grain edge comparing grain center. The cycle and rate performances of the cathode from needle-shape precursor shows superior to those from flake-shape precursor, which might be attributed to low charge-transfer resistance by impedance measurement.

• Proceedings of the KIEE Conference
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• 1993.11a
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• pp.237-239
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• 1993

$MnO_2$ added $(Pb_{0.45}Ca_{0.55})(Fe_{0.5}Nb_{0.5})O_3$ was calcined at $850^{\circ}C$ for two hours and sintered at $1100^{\circ}C$ for two hours. The microstructure was examined using XRD and SEM. The dielectric constant, the quality factor, and the temperature stability was measured using Hakki and Coleman method. Dielectric constant was improved to 94 from 0.5wt% $MnO_2$ added sample with $Q{\cdot}f=4260GHz$ and acceptable ${\tau}_f$ (< $20ppm/^{\circ}C$).

• Korean Journal of Poultry Science
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• v.42 no.3
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• pp.267-274
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• 2015

Peat moss has been found to be useful as a plant growth substance, fertilizer, and soil solution. It is not known, however, whether dietary peat moss affects performance in broilers. In the present study, we investigated the effects of dietary peat moss as a feed ingredient in broilers. Experimental diets were prepared by mixing basal feed with PM at 0.0, 0.2, 0.4, 0.8, and 1.6%. In experiment 1, 150 14-day-old Ross broiler chicks were housed for 2 weeks in 15 pens that were randomly assigned into five groups (0.0%, 0.2%, 0.4%, 0.8% and 1.6% PM). Dietary peat moss at 0.2% and 0.4% significantly increased the water intake, body weight, weight gain and feed efficiency compared with the control (0.0% PM, P<0.05) but did not affect feed intake. Higher levels of PM (0.8 and 1.6%) significantly decreased feed intake, body weight and weight gain. In experiment 2, 198 7-day-old Ross chicks were housed for 3 weeks in nine pens that were randomly assigned into three groups (0.0%, 0.2% and 0.4% PM). When the broilers were fed with dietary peat moss for 3 weeks, the peat moss effects disappeared. The results of the current study show that low amounts of dietary peat moss may exert beneficial effects on performance in broilers.

• Food Science of Animal Resources
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• v.34 no.2
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• pp.178-184
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• 2014

The application of ganghwa mugwort (GM), ascorbic acid (AC), and their combinations for reduction of residual nitrite contents was analyzed in pork sausages during storage of 28 d. Six treatments of pork sausages contained the following: Control (no antioxidant added), AC (0.05% AC), GM 0.1 (0.1% GM), GM 0.2 (0.2% GM), AC+GM 0.1 (0.05% AC + 0.1% GM) and AC+GM 0.2 (0.05% AC + 0.2% GM). Results showed that the mixture of 0.05% AC and 0.2% GM was most effective for reducing thiobarbituric acid reactive substances (TBARS) and residual nitrite contents than the control and GM added sausages alone (p<0.05). The color values of all treatments were significantly affected by adding GM (either alone or with AC). Additionally, the total color difference (${\Delta}E$) and hue angle ($H^{\circ}$) values of treatments added with GM were higher than those of the control as the amount of GM increased (p<0.05). However, there were no significant differences in the pH values between the control and all treatments during the storage period (p>0.05). Our results showed possible applications of antioxidant combination, for preventing the lipid oxidation and decreasing the residual nitrite levels of meat products.