• Journal of Electrical Engineering and Technology
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• v.2 no.2
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• pp.267-273
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• 2007

A depletion-mode MOSFET has been analyzed to evaluate its electrical behavior using a novel 3-D numerical simulation package. The characterizing analysis of the BC MOSFET was performed through short-channel narrow-channel and small-geometry effects that are investigated, in detail, in terms of the threshold voltage. The DIBL effect becomes significant for a short-channel device with a channel length of $<\;3({\mu}m)$. For narrow-channel devices the variation of the threshold voltage was sharp for $<4({\mu}m)$ due to the strong narrow-channel effect. In the case of small-geometry devices, the shift of the threshold voltage was less sensitive due to the combination of the DIBL and substrate bias effects, as compared with that observed from the short-channel and narrow-channel devices. The characterizing analysis of the narrow-channel and small-geometry devices, especially with channel width of $<\;4({\mu}m)$ and channel area of $<\;4{\times}4({\mu}m^2)$ respectively, can be accurately performed only from a 3-D numerical simulation due to their sharp variations in threshold voltages.

• Korean Journal of Agricultural Science
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• v.2 no.2
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• pp.375-380
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• 1975

Effects of light on mycelial growth. pigmentation and sclerotial production of Corticium sasakii were investigated on rice polish agar at $29^{\circ}C=1$. 1) In both isolates. D-3 and D-15. light had no affect on the mycelial growth of C. sasakii. Isolate D-15 did not produce a brown pigment within its mycelium and culture medium in all treatments. but isolate D-3 were more intensively pigmented in light than in darkness. 2) Effect of light on sclerotial production of C. sasakii was different between two isolates. Isolate D-3 produced the most sclerotia in constant light, intermediate in alternating light and darkness and the least in constant darkness. 3) Isolate D-15 produced a little more sclerotia in light than in darkness, but the differences were not statistically significant. However, this isolate produced a larger number of big sclerotia in constant darkness than in constant light and in alternating light and darkness.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.9 no.3
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• pp.822-830
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• 2008

We aim to confirm empirically that a corporate's R&D expenditure effect positively on its value. As a result of the regression analysis on financial statements of KSE and KOSDAQ enterprises, the sum of R&D expenditure effects positively on corporate value. Moreover, we have the result that R&D expenditure appropriated as cost has more effect on corporate value than the expenditure appropriated as asset.

• Journal of information and communication convergence engineering
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• v.12 no.4
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• pp.208-214
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• 2014

In this paper, in order to solve the problems of a narrow viewing angle and the flip effect in a three-dimensional (3D) integral imaging display, we propose an improved system by using an eye tracking method based on the Kinect sensor. In the proposed method, we introduce two types of calibration processes. First process is to perform the calibration between two cameras within Kinect sensor to collect specific 3D information. Second process is to use a space calibration for the coordinate conversion between the Kinect sensor and the coordinate system of the display panel. Our calibration processes can provide the improved performance of estimation for 3D position of the observer's eyes and generate elemental images in real-time speed based on the estimated position. To show the usefulness of the proposed method, we implement an integral imaging display system using the eye tracking process based on our calibration processes and carry out the preliminary experiments by measuring the viewing angle and flipping effect for the reconstructed 3D images. The experimental results reveal that the proposed method extended the viewing angles and removed the flipping images compared with the conventional system.

• YAKHAK HOEJI
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• v.40 no.3
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• pp.357-368
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• 1996

The in vitro antibacterial activity of a novel fluoroquinolone, DWP20373(1-Cyclopropyl-6-fluoro-8-methoxy-7-(2,7-diazabicyclo[3,3,0]oct-4-ene-7-yl)-1,4-dihydro-4 oxoquino line-3carboxylic acid) was compared with those of ciprofloxacin (CPFX), sparfloxacin (SPFX) and ofloxacin (OFLX). DWP20373 was more active than SPFX and OFLX but was less potent than CPFX against gram-negative bacteria. DWP20373 showed an excellent activity against L-MRSA and H-MRSA ($MlC_{90}=0.781{\sim}1.563{\mu}g/ml$).The activity of DWP20373 decreased moderately in the presence of 5mM $Mg^{2+}$. However, pH and serum had no effect on the activity of DWP20373. DWP20373 possessed a rapid bactericidal activity against gram-positive and gram-negative strains.

• Biomolecules & Therapeutics
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• v.24 no.3
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• pp.298-304
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• 2016

Dianthus superbus (D. superbus) is a traditional crude drug used for the treatment of urethritis, carbuncles and carcinomas. The objective of this study was to confirm the cognitive enhancing effect of D. superbus in memory impairment induced mice and to elucidate the possible potential mechanism. Effect of D. superbus on scopolamine induced memory impairment on mice was evaluated using the Morris water maze and passive avoidance tests. We also investigated acetylcholinesterase (AChE) activity and brain-derived neurotropic factor (BDNF) expression in scopolamine-induced mice. HPLC-DAD analysis was performed to identify active compounds in D. superbus. The results revealed that D. superbus attenuated the learning and memory impairment induced by scopolamine. D. superbus also inhibited AChE levels in the hippocampi of the scopolamine-injected mice. Moreover, D. superbus increased BDNF expression in the hippocampus. Eight compounds were identified using HPLC-DAD analysis. The content of 4-hydroxyphenyl acetic acid was higher than contents of other compounds. These results indicated that D. superbus improved memory functioning accompanied by inhibition of AChE and upregulation of BDNF, suggesting that D. superbus may be a useful therapeutic agent for the prevention or treatment of Alzheimer's disease.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.24 no.3
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• pp.24-30
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• 1998

Inhibitory effects of the new material obtained from Areca catechu seed (CC-516) according to a special process, and its applicability to the skin as a cosmetic raw material in terms of its efficacy were presented. Areca catechu extract out of 150 medicinal plants, exhibited high inhibitory effect on the porcine pancreatic elastase ($IC_{50}$ : $40.8{\mu}$g/ml). It also had an inhibitory effect on the human leukocyte elastase ($IC_{50}$ : 48.1$\mu$g/ml), hyaluronidase ($IC_{50}$ : $416{\mu}$g/ml), antioxidative activity ($IC_{50}$ : $45.4\mu$g/ml) and free radical scavenging activity ($SC_{50}$ : $10.2{\mu}$g/ml). The cream contained 3％ of CC-516 improved skin hydration above 16.5％. Especially, the skin elasticity increases more than 35% and skin wrinkles decreased more than 23％. The CC-516 was designed to be utilized in cosmetology. The cream containing 3％ of this product has not only protecting effect on the skin mechanical properties provided by the collagen and the elastin in the derm but also restructuring effect of scarring or aging tissue.

• Journal of Distribution Science
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• v.14 no.3
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• pp.39-44
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• 2016

Purpose - The purpose of this research is to investigate whether Korea's economic growth can be explained by the endogenous growth theory. Specifically, we test whether R&D expenditure has a positive and significant effect on the economic growth. Research design, data, and methodology - We hypothesize that R&D expenditure has a positive effect on the economic growth after adding control variables in the growth equation. Korean annual data from 1963 to 2011 from Science and Technology Annual of the Ministry of Education, Science and Technology, the Bank of Korea, etc. are used. We estimate the growth equation by GMM in addition to OLS. Results - We found that R&D expenditure has a positive and significant effect on the economic growth after adding the ratio of investment to GDP, the ratio of FDI to GDP, the ratio of government expenditure to GDP, inflation and the ratio of trade openness to GDP as control variables in the growth equation. Conclusions - Our results show that Korea's rapid economic growth for the past five decades can be explained by the R&D-based endogenous economic growth theory. Our results suggest that the policy attention of the Korean government be paid to R&D promotion.

• Journal of Korea Technology Innovation Society
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• v.20 no.3
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• pp.546-575
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• 2017

This paper investigates the effects of public R&D support on medium-sized firms' R&D investment. The paper collects a panel dataset of Korean manufacturing firms' R&D investment and public support, and employs the DID (difference-in-differences) regression for the test of stimulating or crowding-out effect. Empirical analysis examines how the effect of public R&D support differs between small and medium-sized firms and whether firm size and technological capability moderate the effect in the sample of medium-sized firms. Empirical results show that public R&D support tends to generally stimulate private pure R&D investment for both small and medium-sized firms. Comparing the results for small and medium-sized firms, this paper finds that the stimulating effect is relatively larger and more significant for medium-sized firms, while the effect is not significant for small ones. Furthermore, the paper shows that the stimulating effect of public R&D subsidy on private R&D investment is relatively stronger for medium-sized firms with superior technological competence and the effect of tax support is greater for incompetent firms. These results suggest that public R&D policies and R&D programs, differentiated from those for existing small firms, are necessary for medium-sized firms to stimulate private R&D continuously and formulated carefully by considering firm size, technological capability and growth potential.

• The Korean Journal of Physiology and Pharmacology
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• v.23 no.2
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• pp.113-120
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• 2019

Mannosylerythritol lipids (MELs) are glycolipids and have several pharmacological efficacies. MELs also show skin-moisturizing efficacy through a yet-unknown underlying mechanism. Aquaporin-3 (AQP3) is a membrane protein that contributes to the water homeostasis of the epidermis, and decreased AQP3 expression following ultraviolet (UV)-irradiation of the skin is associated with reduced skin moisture. No previous study has examined whether the skin-moisturizing effect of MELs might act through the modulation of AQP3 expression. Here, we report for the first time that MELs ameliorate the UVA-induced downregulation of AQP3 in cultured human epidermal keratinocytes (HaCaT keratinocytes). Our results revealed that UVA irradiation decreases AQP3 expression at the protein and messenger RNA (mRNA) levels, but that MEL treatment significantly ameliorated these effects. Our mitogen-activated protein kinase inhibitor analysis revealed that phosphorylation of c-Jun N-terminal kinase (JNK), but not extracellular signal-regulated kinase or p38, mediates UVA-induced AQP3 downregulation, and that MEL treatment significantly suppressed the UVA-induced phosphorylation of JNK. To explore a possible mechanism, we tested whether MELs could regulate the expression of peroxidase proliferator-activated receptor gamma ($PPAR-{\gamma}$), which acts as a potent transcription factor for AQP3 expression. Interestingly, UVA irradiation significantly inhibited the mRNA expression of $PPAR-{\gamma}$ in HaCaT keratinocytes, whereas a JNK inhibitor and MELs significantly rescued this effect. Taken together, these findings suggest that MELs ameliorate UVA-induced AQP3 downregulation in HaCaT keratinocytes by suppressing JNK activation to block the decrease of $PPAR-{\gamma}$. Collectively, our findings suggest that MELs can be used as a potential ingredient that modulates AQP3 expression to improve skin moisturization following UVA irradiation-induced damage.