• Communications of the Korean Mathematical Society
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• v.10 no.3
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• pp.681-688
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• 1995

Fixed-point theory has an extension to coincidences. For a pair of maps $f,g:X_1 \to X_2$, a coincidence of f and g is a point $x \in X_1$ such that $f(x) = g(x)$, and $Coin(f,g) = {x \in X_1 $\mid$ f(x) = g(x)}$ is the coincidence set of f and g. The Nielsen coincidence number N(f,g) and the Lefschetz coincidence number L(f,g) are used to estimate the cardinality of Coin(f,g). The aspherical manifolds whose fundamental group has a normal solvable subgroup of finite index is called infrasolvmanifolds. We show that if $M_1,M_2$ are compact connected orientable infrasolvmanifolds, then $N(f,g) \geq $\mid$L(f,g)$\mid$$ for every $f,g : M_1 \to M_2$.

• International journal of advanced smart convergence
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• v.11 no.3
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• pp.1-6
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• 2022

In this paper, we estimate the mean number of objects in the M/H₂/1 model for web service when the mean object size in the M/H₂/1 model is equal to that of the M/G/1/PS and M/BP/1 models. To this end, we use the mean object size obtained by assuming that the mean latency of deterministic model is equal to that of M/H₂/1, M/G/1/PS, and M/BP/1 models, respectively. Computational experiments show that if the shape parameter of the M/BP/1 model is 1.1 and the system load is greater than 0.35, the mean number of objects in the M/H₂/1 model when mean object size of M/H₂/1 model is the same as that of M/G/1/PS model is almost equal to the mean number of objects in the M/H₂/1 model when the mean object size of M/H₂/1 model is the same as that of M/BP/1 model. In addition, as the upper limit of the M/BP/1 model increases, the number of objects in the M/H₂/1 model converges to one, which increases latency. These results mean that it is efficient to use small-sized objects in the web service environment.

• Journal of the East Asian Society of Dietary Life
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• v.19 no.3
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• pp.384-394
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• 2009

This study was performed to determine the antioxidative and anticancer effects of extracts from Adenophora remotiflora leaves. The antioxidative effects of the extracts were measured using 1,1-diphenyl-2-picrylhydrazyl (DPPH)-radical scavenging activity and hemoglobin-induced linoleic acid oxidative inhibition assays. The results indicated that the extracts had stronger effects than the synthetic antioxidant BHT at the same concentration. The $SC_{50}$ values (50% radical scavenging effect on $1{\times}10^{-4}$ M DPPH) of the methanol fraction, water extract, and BHT were 47.5 ${\mu}g$/mL, 74.6 ${\mu}g$/mL and 102.2 ${\mu}g$/mL, respectively. In addition the $IC_{50}$ values (hemoglobin-induced linoleic acid oxidation inhibition) of the methanol fraction, water extract, and BHT were 120.8 ${\mu}g$/mL, 135.6 ${\mu}g$/mL, and 150.2 ${\mu}g$/mL, respectively. This research also assessed decreases in the survival of BNLcl2 cells (normal liver cells) by solvent fractions of the A. remotiflora leaf extracts at various concentrations (1, 5, 10, 25, 50, 100, 250, 500, 1,000, 2,000 ${\mu}g$/mL). The water extract did not decrease survival at any of the concentrations when compared to the control group. The hexane, ethyl acetate, and methanol fractions decreased survival as compared to the control group by inducing cell toxicity at a concentration of 1,000 ${\mu}g$/mL and above. Therefore, an anticancer activity experiment was conducted using concentrations below 500 ${\mu}g$/mL. At 500 ${\mu}g$/mL, the methanol fraction decreased A549 cell (human lung carcinoma cells) survival by 46% as compared to the control group, presenting the greatest effect against cell survival. All extracts showed greater anticancer activity in Hep G2 cells (human liver carcinoma cells) as compared to the A549 cells. For the Hep G2 cells, the methanol extract decreased survival by 28% as compared to the control group at the concentration of 500 ${\mu}g$/mL, thus restraining lung cancer cell growth.

• Applied Biological Chemistry
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• v.30 no.1
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• pp.77-87
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• 1987

The mutant with high productivity, X. malvacearum SNUF 560-6, was acquired from the X. malvacearum SNUF 560 with low productivity by UV-light irradiation. It was preserved is lyophilized stock culture and it was transferred to PDA slant to maintain viability fortnightly. Fermentations were started by retransfering to MY agar slant from PDA stok culture. The experiments for optimal xanthan gum production were studied in a chemically defined medium. Of the carbon and nitrogen sources tested, 0.4% sucrose medium and 10mM glutamic acid medium yielded the highest xanthan gun production respectively. The addition of 10g/l succinic acid stimulated xanthan gum production. Also 65mM $PO_4\;^{-3}\;(12.6g/l\;KH_2PO_4)$ was effective on xanthan gum production. Finally, medium 1 and medium 2 which have high xanthan gum production potencies were achieved in this stud. The components of medium 1 and medium 2 were as follows: Medium 1 : sucrose 40g/l glutamate 10mM $PO_4\;^{-3}\;54mM\;(KH_2PO_4\;12.65g/l)$ Citrate 2g/l $MgSO_4{\cdot}7H_2O\;0.2g/l$ $H_3BO_3\;0.005/l$ ZnO 0.006/l $FeCl_2{\cdot}6H_2O\;0.0024g/l$ $CaCO_3\;0.02g/l$ Medium 2 : $Sucrose\;40g/l\;(NH_4)_2SO_4\;2g/l$ $PO_4\;^{-3}\;65mM\;(KH_2PO_4\;12.65g/l)$ Succinate 10g/l $MgSO_4{\cdot}7H_2O\;0.02g/l$ $H_3BO_3\;0.06g/l$ ZnO 0.006g/l $FeCl_2{\cdot}6H_2O\;0.0024g/l$ $CaCO_3\;0.02g/l$.

• Journal of Korean Society of Occupational and Environmental Hygiene
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• v.29 no.1
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• pp.34-41
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• 2019

Objective: This study is conducted to evaluate airborne lead concentration in and around lead production plant. Methods: Airborne lead concentration was monitored simultaneously inside of the processes of lead recycling factory and outside of factory which include stack, boundary of factory and residential area 1 km and 7.5 km from factory, respectively. All samples were measured three times at 1.5 m from the ground and analyzed using inductively coupled plasma mass spectrometer, inductively coupled plasma optical emission spectrometer or flame atomic absorption spectrometer. Results: All airborne lead concentrations measured inside of factory($13.9{\mu}g/m^3-252.9{\mu}g/m^3$) and outside of factory($0.001{\mu}g/m^3-54.97{\mu}g/m^3$) showed log-normal distribution. Geometric mean lead concentration, $54.81{\mu}g/m^3$, measured inside of factory was significantly higher than outside of factory, $0.20{\mu}g/m^3$(p<0.01). Among the samples measured inside the factory, lead concentration was the highest in the refining process($59.02{\mu}g/m^3-252.9{\mu}g/m^3$). In the case of the samples outside the factory, the nearest chimney was the highest($3.84{\mu}g/m^3-54.97{\mu}g/m^3$), and the lead concentration at the farthest place, 7.5 km from the factory was the lowest($0.001{\mu}g/m^3-1.7{\mu}g/m^3$). The arithmetic lead concentration, $0.45{\mu}g/m^3$ in the residential area near the factory was below the atmospheric environment standard of $0.5{\mu}g/m^3$, but the maximum concentration of $3.4{\mu}g/m^3$ was exceeded. Conclusions: Airborne lead concentration in residential area, 1 km away from lead recycling plant, may exceed ambient air standard of $0.5{\mu}g/m^3$.

• The Korean Journal of Pharmacology
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• v.9 no.1
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• pp.59-63
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• 1973

Although numerous drugs are available for the treatment of superficial fungi infections of skin, and yet the clinical effects of most of such drugs are not satisfactory. In the hope of searching for effective drugs for superficial fungi infections, the authors observed fungistatic effects of Pyrethri Flos, a common herb in Korea, with water extract (PFWE), ethanol extract (PFEE), and methanol extract (PFME) from Pyrethrum cinerariaefolium V. In in vitro studies, the spores of fungi were inoculated on Sabouraud's glucose agar media which contained Pyrethri Flos extracts in each concentrations of $500\;{\mu}g/ml$, $1,000\;{\mu}g/ml$ and $5,000\;{\mu}g/ml$ respectively, and the growth of the fungi was observed for 3 weeks. The species of the fungi used in these experiments were Epidermophyton floccosum, Microsporum canis, Microsporum nanum, Microsporum gypseum, Microsporum cookei, Trichophyton rubrum, Trichophyton mentagrophytes, Trichophyton tonsurans and Trichophyton verrucosum. The results of these studies were as follows; 1. The growth of M. nanum & T. rubrum was slightly inhibited by PFWE $500\;{\mu}g/ml$, and the growth of M. nanum, M. cookei & T. rubrum was slightly inhibited by PFWE $1,000\;{\mu}g/ml$. The growth of E. floccosum, M. gypseum & M. cookei was slightly inhibited, however the growth of M. canis, M. nanum, T. mentagrophytes, T. rubrum & T. tonsurans was significantly inhibited by PFWE $5,000\;{\mu}g/ml$. With $500\;{\mu}g/ml$ of PFEE, the growth of M. canis, M. nanum, T. mentagrophytes, T. rubrum & T. tonsurans was significantly inhibited, and moderate inhibition of M. cookei growth and slight inhibition E. floccosum & M. gypseum were observed. The growth of M. canis, M. nanum, T. mentagrophytes, T. rubrum & T. tonsurans was significantly inhibited, and the growth of E. floccosum, M. gypseum & M. cookei was moderately inhibited by PFEE $1,000\;{\mu}g/ml$. Significant inhibitions of the growth of E. floccosum, M. canis, M. nanum, M. gypseum, M. cookei, T. mentagrophytes, T. rubrum & T. tonsurans were observed by PFEE $5,000\;{\mu}g/ml$. 3. The growth of E. floccosum & M. cookei was moderately inhibited, and the growth of M. canis, M. nanum, M. gypseum, M. mentagrophytes, T. rubrum & T. tonsurans was significantly inhibited by PFME $500\;{\mu}g/ml$. But the growth of E. floccosum, M. canis, M. nanum, M. gypseum, M. cookei, T. mentagrophytes, T, rubrum & T. tonsurans was significantly inhibited, and the growth of T. verrucosum was slightly inhibited in both PFME $1,000\;{\mu}g/ml$ and $5,000\;{\mu}g/ml$.

• Journal of Environmental Impact Assessment
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• v.27 no.5
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• pp.509-520
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• 2018

The impact of meteorological condition on surface $PM_{10}$ concentrations in South Korea was quantitatively simulated from 2010 to 2014 using WRF (ver.3.8.1) and CMAQ (5.0.2) model. The result showed that seasonal standard deviations of PM10 induced by change of weather conditions were $4.8{\mu}g/m^3$, $1.7{\mu}g/m^3$, $1.7{\mu}g/m^3$, $4.2{\mu}g/m^3$ for spring, summer, autumn and winter compared to 2010, respectively, with the annual mean standard deviation of about $2.6{\mu}g/m^3$. The results of 18 regions in South Korea showed standard deviation of more than $1{\mu}g/m^3$ in all regions and more than $2{\mu}g/m^3$ in Seoul, Northern Gyeonggi, Southern Southern Gyeonggi, Western Gangwon and Northern Chungcheong in South Korea.

• Korean Journal of Environmental Agriculture
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• v.42 no.4
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• pp.389-395
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• 2023

This study evaluated the effects of gibberellic acid (GA₃) on the growth and quality of creeping bentgrass (Agrostis palustris Huds.). Experimental treatments included a No application of fertilizer and GA₃ (NFG) Control [3 N active ingredient (a.i.) g/m²], 0.3GA₃ (GA₃ 0.3 a.i. mg/m²/200 mL), 0.6GA₃ (GA₃ 0.6 a.i. mg/m²/200 mL), 1.2GA₃ (GA₃ 1.2 a.i. mg/m²/200 mL), and 2.4GA₃ (GA₃ 2.4 a.i. mg/m²/200 mL). Additionally, the study included a 1.5N+GA₃ experiment with similar GA₃ treatments combined with 1.5N a.i. g/m² : NFG, Control (3N a.i. g/m²), 1.5N+ 0.3GA₃ (1.5N a.i. g/m²+GA₃ 0.3 a.i. mg/m²/200 mL), 1.5N+0.6GA₃ (1.5N a.i. g/m²+GA₃ 0.6 a.i. mg/m²/200 mL), 1.5N+1.2GA₃ (1.5N a.i. g/m²+GA₃ 1.2 a.i. mg/m²/ 200 mL), and 1.5N+2.4GA₃ (1.5N a.i. g/m²+GA₃ 2.4 a.i. mg/m²/200 mL). Compared to the NFG, turf color index chlorophyll content was not significantly different (p< 0.05). However, shoot length in 1.2GA₃, 2.4GA₃, 1.5N+0.3GA₃, 1.5N+0.6GA₃, 1.5N+1.2GA₃, and 1.5N+2.4GA₃ treatments increased by 0.8%, 10.6%, 5.15%, 8.3%, 13.5 %, and 21.6%, respectively, compared to the control. As compared to the control, clipping yield in 1.5N+1.2GA₃ and 1.5N+2.4GA₃ treatments increased by 7.1% and 14.3 %, respectively. These results indicated that GA₃ application increased shoot length, with the 1.2GA₃ treatment showing shoot length similar to the control (3N a.i. g /m² ).

• Communications of the Korean Mathematical Society
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• v.21 no.3
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• pp.475-490
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• 2006

We give a way to obtain formulas for ${\pi}*{\psi}^{\kappa}_{n+1}$ in terms ${\psi}$ and ${\lambda}-classes$ where ${\pi}=\bar M_{g,n+1}{\rightarrow}\bar M_{g,n}(g=0,\;1,\;2)$ by the localization theorem. By using the formulas, we obtain Kontsevich-Manin type reconstruction theorems for $\bar M_{0,\;n}(\mathbb{R^m}),\;\bar M_{1,\;n},\;and\;\bar M_{2,\;n}$. We also (re)produce a lot of well-known relations in tautological rings, such as WDVV equation, the Mumford relations, the string and dilaton equations (g = 0, 1, 2) etc. and new formulas for ${\pi}*({\lambda}_g{\psi}^{\kappa}_{n+1}+...+{\psi}^{g+{\kappa}_{n+1}$.

• Journal of Korean Institute of Industrial Engineers
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• v.28 no.1
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• pp.36-43
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• 2002

We analyze bulk service $M/G^{b}/1$ queues using the arrival time approach of Chae et al. (2001). As a result, the decomposition property of the M/G/1 queue with generalized vacations is extended to the $M/G^{b}/1$ queue in which the batch size is exactly a constant b. We also demonstrate that the arrival time approach is useful for relating the time-average queue length PGF to that of the departure time, both for the $M/G^{b}/1$queue in which the batch size is as big as possible but up to the maximum of constant b. The case that the batch size is a random variable is also briefly mentioned.