• Korean Journal of Mathematics
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• v.20 no.3
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• pp.353-360
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• 2012

In this paper we introduce the property (C), which is a cone metric extension of the usual metric property (E,A) and consider fixed point theorems for generalized contractive mappings under suitable conditions in cone metric spaces without normal cones.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2008.04a
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• pp.26-28
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• 2008

This paper is to investigate the existence theorem for the semilinear fuzzy integrodifferential equation in ${E_N}$ by using the concept of fuzzy number whose values are normal, convex, upper semicontinuous and compactly supported interval in ${E_N}$. Main tool is successive iteration method.

• The Mathematical Education
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• v.20 no.3
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• pp.23-26
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• 1982

Many interesting properties of a space curve C in E$^3$ may be investigated by means of the concept of spherical indicatrix of tangent, principal normal, or binormal, to C. The purpose of the present paper is to derive the representations of the Frenet frame field., curvature, and torsion of spherical indicatrix to C in terms of the quantities associated with C. Furthermore, several interesting properties of spherical indicatrix are found in the present paper.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2000.07a
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• pp.616-619
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• 2000

It is important to control the plasma characteristics for high quality plasma process. Recently, a novel method proposed by us, named as Enhanced-ICP, using periodic weak time-varying axial magnetic field added to a normal ICP source, has improved etch characteristics much. Variation of plasma characteristics according to the frequency of time-varying axial magnetic field have been measured and analyzed.

• Journal of the Korean Institute of Intelligent Systems
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• v.18 no.4
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• pp.543-548
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• 2008

This paper is to investigate the existence theorem for the semilinear fuzzy integrodifferential equation in $E_N$ by using the concept of fuzzy number whose values are normal, convex, upper semicontinuous and compactly supported interval in $E_N$. Main tool is successive iteration method.

• Bulletin of the Korean Mathematical Society
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• v.56 no.4
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• pp.853-865
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• 2019

In this paper, we consider gradient estimates for positive solutions to the following nonlinear elliptic equation on a complete Riemannian manifold: $${\Delta}_Vu+cu^{\alpha}=0$$, where c, ${\alpha}$ are two real constants and $c{\neq}0$. By applying Bochner formula and the maximum principle, we obtain local gradient estimates for positive solutions of the above equation on complete Riemannian manifolds with Bakry-${\acute{E}}mery$ Ricci curvature bounded from below, which generalize some results of [8].

• Journal of Life Science
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• v.21 no.11
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• pp.1501-1510
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• 2011

In recent years novel potential pharmocological candidates have been looked for in animal, seaweed, sponge, fungi and marine bacteria resources. In this study, matrix metalloproteinases (MMPs) that play an important role in metastasis, arthritis, chronic inflammation and wrinkle formation were used as target enzymes to screen therapeutic agents. The inhibitory effects of several marine algae including green algae (5 species), red algae (18 species) and brown algae (4 species) methanolic extracts on MMPs were investigated in human dermal fibroblasts and human fibrosarcoma cell line (HT1080 cells) using gelatin zymography. In human dermal fibroblasts, the inhibition of MMP-2 was observed in Laurencia okamurae, Polysiphonia japonica, Grateloupia lanceolate and Sinkoraena lancifolia of red algae. In contrast, MMP-2 activation was enhanced in Enteromorpha compressa and E. linza of green algae, and Peltaronia bighamiae and Sargassum thunbergii of brown algae. In human fibrosarcoma cells, MMP-9 activation was decreased in the presence of S. thunbergii of brown algae, Polysiphonia japonica in red algae and E. compressa and E. linza of green algae. The interesting finding is that E. compressa and E. linza of green algae, and S. thunbergii of brown algae exhibited a positive effect on MMP-2 in normal cells, but a negative effect on MMP-9 in cancer cell lines. These results suggest that E. compressa and E. linza of green algae, and S. thunbergii of brown algae contain potential therapeutic ingredients for cancer treatment.

• Korean Journal of Community Nutrition
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• v.5 no.4
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• pp.633-641
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• 2000

This study was conducted to measure the difference in the total antioxidant status(TAS) of overweight and normal weight adults, and to investigate the correlation between TAS and the nutrient intake. Anthropometric parameter, TAS, biochemical parameters and dietary intake were measured in the normal weight group(n=17, BMI 20-25, obesity index 90-110%, body fat 16-20%) and overweight group(n=13, BMI > 25, obesity index > 120%, body fat > 25%) among Korean young males. The TAS of the overweight group was significantly higher than that of the normal weight group(p < 0.01). Among biochemical parameters, the average uric acid concentration of the overweight group was significantly higher(p < 0.05) compared to that of the normal weight group indicating, the uric acid concentration reflects TAS. Usual dietary intake showed that the intakes of Ca and vitamin B$_2$, are below RDA. The average intake of vitamin C in the overweight group was significantly lower than that in the normal group(p < 0.05). There was no difference in the intake of carotene and vitamin E between groups. The diet quality of both groups was satisfactory. The result of the correlation analysis on TAS, the uric acid concentration, and the measured indexs are as follows : In the overweight group, TAS was negatively correlated with alchol drinking, and uric acid concentration was positively correlated with BMI, obesity index, and TAS. In conclusion, TAS was significantly higher in the overweight group than that of the normal group, although no association was found with nutrient intakes. Serum uric acid showed a positive relationship with TAS indicating, it is a possible determinant of the antioxidant capacity.

• Journal of the Society of Disaster Information
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• v.18 no.1
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• pp.80-90
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• 2022

Purpose: The objective of this study was to improve smart monitoring and monitoring management technology in long tunnels by investigating and analyzing the normal operation rates of monitoring hardware in the long tunnels of high-speed and urban railways. Method: This study evaluated, analyzed, and compared the normal operation rate of 6-8 types of monitoring hardware for each long tunnel, targeting three high-speed railway lines with a long tunnel (i.e., Suseo-Pyeongtaek Line, Gyeongbu Line, and Honam Line) and two urban railway groups with a long tunnel (i.e., Seoul Metro Lines 5, 6, and 7, and 9). Result: The rank of the normal operation rate of monitoring hardware was in the order of Suseo-Pyeongtaek High-Speed Railway (92.1%), Seoul Metro Lines 5, 6, and 7 (85.8%), Seoul Metro Line 9 (85.2%), Gyeongbu High-speed Railway (80.5%), and Honam High-speed Railway (46.7%). Conclusion: The mean normal operation rate of the monitoring hardware in the three high-speed railway long tunnels was 83.4%, and that of the two urban railway long tunnels was 85.5%, indicating that the deviation between them was small. The mean normal operation rate of the monitoring hardware in the long tunnels of the five high-speed and urban railway lines was 84.2%.

• Asian-Australasian Journal of Animal Sciences
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• v.23 no.7
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• pp.916-923
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• 2010

We report nutritional physiology and non-specific immune responses of vitamin E in parrot fish for the first time. This study aimed to investigate the essentiality and requirements in diets based on growth performances, non-specific immune responses and a challenge test against Vibrio angullarum. Six casein-gelatin based semi-purified diets were formulated to contain six graded levels of DL-${\alpha}$-tocopheryl acetate (${\alpha}$-TA) at 0, 25, 50, 75, 100 and 500 mg/kg diet (designated as E0, E25, E50, E75, E100 and E500, respectively) and fed to triplicate groups of juvenile parrot fish for 12 weeks. The analyzed dietary concentrations of vitamin E were 0, 38, 53, 87, 119 and 538 mg/kg diet for E0, E25, E50, E75, E100 and E500, respectively. At the end of the feeding trial, growth performance and feed utilization of fish fed the E25 were significantly higher compared to that of fish fed the other diets. Liver ${\alpha}$-tocopherol concentration was significantly increased with an increase in dietary ${\alpha}$-TA in a dose dependent manner. No apparent clinical signs of vitamin E deficiency and mortality were observed in fish fed the basal diet for 12 weeks. Among the immune responses assayed, phagocytic (NBT assay) and myeloperoxidase activities were significantly increased with increment of dietary ${\alpha}$-TA levels. During the challenge test with V. anguillarum, E75, E100, and E500 diets resulted in higher survivals than E0, E25 and E50 diets. The findings of this study suggest that parrot fish require exogenous vitamin E and the optimum dietary level could be approximately 38 mg ${\alpha}$-TA/kg diet for normal growth and physiology. Dietary ${\alpha}$-TA concentration over 500 mg/kg could be required to enhance the nonspecific immune responses and improve the resistance of juvenile parrot fish against V. anguillarum.