• Journal of Korean Society on Water Environment
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• v.30 no.1
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• pp.1-7
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• 2014

The purpose of this study was to investigate the nitrification characteristics of biological aerated filter (BAF) packed with ceramic media, especially focusing on nitrite build-up during nitrification. When increasing the nitrogen load above $1.63kgNH_4{^+}-N/m^3{\cdot}d$, ammonium removal efficiency decreased to less than 60% and the nitrite ratio ($NO_2{^-}-N/NO_x-N$) of higher than 75% was achieved due to the inhibitory free ammonia (FA, $NH_3-N$) concentration and oxygen limitation. FA inhibition, however, is not recommended strategy to promote nitrite build-up since FA concentration in the reactor is coupled with decreased ammonium removal efficiency. Nitrite ratio in the effluent was also affected by aeration rate and influent ammonium concentration. Ammonium oxidation was enhanced at a higher aeration rate regardless of influent ammonium concentration but, the nitrite ratio was dependent on both aeration rate and influent ammonium concentration. While a higher nitrite ratio was obtained when BAFs were fed with $50mgNH_4{^+}-N/L$ of influent, the nitrite ratio significantly decreased for a greater influent concentration of $200-300mgNH_4{^+}-N/L$. Taken together, aeration rate, influent ammonium concentration and FA concentrations kept in the BAF were found to be critical variables for nitrite accumulation in the BAF system.

• The Korean Journal of Health Service Management
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• v.12 no.1
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• pp.1-11
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• 2018

Objectives : The purpose of this study was to identify the relationship between decision-making types, public entrepreneurship, and performance management of local public hospital directors. Methods : A questionnaire survey was carried out to assess the dependent variables of directors' decision-making types and public entrepreneurship. The analysis of management performance was carried out through a comparison between 2016 results of, data of variation rate on medical revenue and change rate on medical profit and results in 2015. Results : Results indicated that local public hospital directors who used rational decision-making showed better performance management. The analysis showed that enterprise had a greater positive effect (+) on variation rate of medical revenue than that of innovation. However, innovation had a higher positive effect (+) on change rate of medical profit than that of enterprise. These results suggest that innovation and enterprise have a major influence on performance management. Conclusions : The survey used for this study suggests that an education and training program is needed to improve public hospital directors' ability for rational decision-making, public entrepreneurship and performance management. Additionally, the policy change guaranteeing autonomy within the proper range is demanded that Local Public Hospital Director having spirit of innovation and enterprise achieves peak capacity and have responsibility for management.

• Korean Journal of Animal Reproduction
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• v.16 no.3
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• pp.261-267
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• 1992

The reproductive performance of SPF ICR mice under single paired mating were examined to get reproductive background data and to establish single paired rotational mating system. The results obtained were as follows : average litter size was 15.4$\pm$2.0 heads ; average weaning rate was 95.7$\pm$4.9% ; sex ratio(male/female) was 1.09$\pm$0.26 ; aveage delivery interval was 23.0$\pm$2.4 days. It was given the largest litter size at the age of 121~150 days and in 2nd~4th parities, but at the age of under 90 days and in 1st parity weaning rate and delivery interval were higher and shorter than those of the other ages and parities, respectively. In sex ratio, the number of male litters was slightly increased from that of female litters. The weaning rate of litters from dams which nuresed 12 litters was the highest among those of different litter sizes, and it was decreased dependent upon increment of litter size. There were no difference among 4 groups for reproductive performance, therefore the present study could have important sources for animal breeders who produce mice using the single paired rotational mating system.

• The Korean Journal of Health Service Management
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• v.8 no.2
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• pp.11-22
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• 2014

This study purposed to analyze the regional variation of the local-out rates of inpatient services. Multiple data sources collected from National Health Insurance Corporation and statistics Korea were merged to produce the analysis data set. The unit of analysis in this study was city, Gun, Gu, and all of them were included in analysis. The dependent variable measured the local-out rate of inpatient cost in study regions. Local environments were measured by variables in three dimensions: provider factors, socio-demographic factors, and health status. Along with the traditional ordinary least square (OLS) based regression model, geographically weighted regression (GWR) model were applied to test their effects. SPSS v21 and ArcMap v10.2 were applied for the statistical analysis. Results from OLS regression showed that most variables had significant relationships with the local-out rate of inpatient services. However, some variables had shown diverse directions in regression coefficients depending on regions in GWR. This implied that the study variables might not have consistent effects and they may varied depending the locations.

• Transactions on Electrical and Electronic Materials
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• v.11 no.2
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• pp.61-64
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• 2010

In this paper, we investigate the quality difference of SiC crystals grown by a conventional physical vapor transport method using various SiC powders. While the growth rate was revealed to be dependent upon the particle size of the SiC powder, the growth rate of SiC bulk crystals grown using SiC powder with a smaller particle size (20 nm) was definitely higher than those using lager particle sizes with $0.1-0.2\;{\mu}m$ and $1-10\;{\mu}m$, respectively. All grown 2 inch SiC single crystals were proven to be the polytype of 6H-SiC and the carrier concentration levels of about $10^{17}\;cm^3$ were determined from Hall measurements. It was revealed that the particle size and process method of SiC powder played an important role in obtaining a good quality, high growth rate, and to reduce growth temperature.

• Journal of the Korean Chemical Society
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• v.26 no.6
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• pp.407-413
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• 1982

The rate constants of the nucleophilic addition of cysteine to 3,4-methylenedioxyphenylmethylene malononitrile were determined by UV Spectrophotometry and a rate equation which can be applied over wide pH range was obtained. On the basis of rate equation, it may be concluded that the rate constants were dependent upon only the concentration of hydroxide ion above pH 9.0, however, below pH 6.0, the reaction were initiated by the addition of neutral cysteine molecule to carbon-carbon double bond and at pH 7.0~9.0, the addition of a neutral cysteine molecule and it's anion occurred competitively.

• Korean Journal of Crystallography
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• v.14 no.1
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• pp.35-38
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• 2003

A simple multistep-concentration setting in capillaries was used to control the water-evaporation rate in vapor-diffusion protein crystallization. In the method used, a variety of evaporation rate curves were obtained by using the secondary precipitant solution referred to as “regulatory solution”, which is not directly exposed to the protein solution. The curves were applied to the crystallization of lysozyme as a model protein. The results clearly showed that crystal growth is dependent on the evaporation rate. Especially, the decoupling curves in which precipitant concentration in protein solutions increases to a certain point and then decreases to the equilibrium concentration gave the best crystals.

• Journal of Pharmaceutical Investigation
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• v.29 no.4
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• pp.323-327
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• 1999

To protect ${\beta}-carotene$ at the stomach and to release rapidly at the intestine we prepared alginate beads containing ${\beta}-carotene$. ${\beta}-carotene$ and alginate solution was homogenized and prepared o/w emulsion was prepared. It was poured into $Ca^{2+}$ solution through syringe needle. The gel was formed spontaneously and alginate beads containing ${\beta}-carotene$ were prepared. ${\beta}-Carotene$ was incorporated into the beads more than 95%. The release rate of ${\beta}-carotene$ was dependent on the concentration of $Ca^{2+}$, ${\beta}-carotene$ and surfactants. However, the concentration of alginate did not affect the release rate of ${\beta}-carotene$. The high concentration of $Ca^{2+}$ slowed down the release rate of ${\beta}-carotene$. The addition of surfactants in the ${\beta}-carotene$beads increased the release rate of ${\beta}-carotene$ in the order of Tween 80 > Cremophor > Span 20. The contents of ${\beta}-carotene$ and diameter of ${\beta}-carotene$ beads did not change significantly at $50^{\circ}C$ for 20 days.

• The Journal of Asian Finance, Economics and Business
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• v.7 no.11
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• pp.75-81
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• 2020

This study aims to empirically test the effect of liquidity and adequacy on bank performance through interest rate risk and credit risk. Capital adequacy and liquidity are variables that can affect the ups and downs of opinion, where the bank's performance in this study is the dependent variable. Good credit distribution can minimize the occurrence of defaults. This study uses banking companies in Indonesia that are listed on the Indonesian stock exchange, with a total number of 43 banking companies, this study however, uses only 30 companies ranging from years 2014 to 2019, primarily due to the availability of the limited data. The data analysis techniques used in this study is PLS-SEM with the WarpPLS application. The research results show that capital adequacy and liquidity has a positive effect on bank performance, interest rate risk and credit risk can mediate capital adequacy on bank performance, interest rate risk can mediate liquidity on bank performance, and interest rate risk has a positive effect on bank performance. However, credit risk can't mediate liquidity on bank performance and credit risk does not have a positive effect on bank performance. This is in line with the commercial loan theory, shiftability theory and the doctrine of anticipated income, which explains how best to give credit, both in longer and the shorter term.

• Archives of Pharmacal Research
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• v.11 no.1
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• pp.65-73
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• 1988

The effects of clonidine on the negative chronotropic response induced by stimulation of vagus nerve were studied in the presence of propranolol in reserpinized and anesthetized rats. When the heart rate was decreased by stimulation of the vagus nerve, clonidine significantly inhibited vagally induced heart rate decrease (negative chronotropic response) in dose dependent manner. This inhibitory effect of clonidine was virtually abolished by phentolamine, ${\alpha}_1-\;and\;{\alpha}_2-adrenoceptor$ antagonist, and partially antagonized by prazosin, ${\alpha}_1-adrenoceptor$ antagonist. On the other hand, when the heart rate was decreased by the infusion of bethanechol, a muscarinic parasympathetic stimulant, clonidine had no effect on the bethanechol-induced heart rate decrease. These results suggest that clonidine inhibits vagally induced negative chronotropic response by activation of presynaptic ${\alpha}-adrenoceptors$ located on the parasympathetic cholinergic nerve terminal in the heart and this effect of clonidine is more related to ${\alpha}_2-adrenoceptors$ than ${\alpha}_1-adrenoceptors$.