• Korea-Australia Rheology Journal
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• v.19 no.3
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• pp.141-146
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• 2007

We examine the wall contact of a $3\;{\mu}m$ tethered DNA chain's free end under shear with a focus on developing schemes for double-tethering in the application of making scaffolds for molecular wires. At this scale our results are found to be highly dependent on small length scale rigidity. Chain-end-wall contact frequency, mean fractional extension deficit upon contact, and standard deviation in extension upon contact are examined for scaling with dimensionless flow strength, Wi. Predictions made using a one dimensional approximation to the Smoluchowski equation for a dumbbell and three dimensional dumbbell simulations produce extension deficit, standard deviation, and frequency scaling exponents of -1/3, -1/3, and 2/3, respectively whereas more fine-grained Kratky-Porod (KP) simulations produce scaling exponents of -0.48, -0.42, and 0.76. The contact frequency scaling of 2/3 is derived from the known results regarding cyclic dynamics Analytical scaling predictions are in agreement with those previously proposed for ${\lambda}-DNA$. [Ladoux and Doyle, 2000, Doyle et al., 2000]. Our results suggest that the differences between the dumbbell and the KP model are associated with the addition of chain discretization and the correct bending potential in the latter. These scaling results will aide future exploration in double tethering of DNA to a surface.

• Journal of the Korean Society of Visualization
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• v.8 no.1
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• pp.46-52
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• 2010

In the present study, we employed the confocal laser scanning microscopy (CLSM) system to visualize the blood flow field with $1{\times}1{\mu}m^2$ spatial resolution. Based on the confocal microscopic image of red blood cells (RBCs), we performed the velocity vector field measurement and evaluated characteristics of cell migration from the cell depleted layer thickness calculation. The rat and mouse's blood were supplied into a micro glass tubes in vitro. The line scanning rate of confocal microscopy was 15 kHz for a $500{\times}500$ pixels image. As a result, the red blood cell itself can be used as a tracer directly without any kind of invasive tracer particle to get the velocity vector field of blood flow by performing particle image velocimetry (PIV) technique.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.36 no.12B
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• pp.1442-1449
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• 2011

In this article, we propose a new method for precise WLAN (Wireless Area Network) AP (Access Point) localization using GPS information measured in the smart phone. The idea is that the possible area of WLAN AP location, called AP_Area, is first determined by measuring GPS information and the received signal strength in the smart phones. As the number of measurements from the smart phones increases, the AP_Area are successively narrowed down to the actual AP location. We have performed the simulation to evaluate the proposed algorithm. The simulation results show that the proposed algorithm can detect the Wi-Fi AP localization within 5 m (probability over than 90%).

• Journal of the Korean Ceramic Society
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• v.51 no.4
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• pp.337-343
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• 2014

A single layer ultrafiltration(UF) ceramic membrane was prepared using boehmite sol. Boehmite was synthesized using a typical sol-gel process with optimization of the viscosity, pH, molar ratio of aluminum isopropoxide(AIP) and $HNO_3$. Boehmite sol was coated on a microfiltration(MF) support using the dip-coating method. MF support was dipped into the boehmite sol with a withdrawal speed of 5 mm/s and was maintained for 10 s in the boehmite sol, resulting in a uniform UF membrane layer of $10{\mu}m$ thickness. The porosity of the obtained membrane was measured and found to be 41.2%; the pore size was found to range from 80~100 nm, corresponding to the pore size of the UF membrane. The flux of the obtained membrane was initially 540 $L/m^2h$ and approximately 85% of the initial flux was recovered using a periodic back-flushing process.

• Journal of electromagnetic engineering and science
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• v.7 no.2
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• pp.91-95
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• 2007

In this paper, a new linearization method has been proposed for a CMOS low noise amplifier(LNA) using the Post IM3 Compensator. The fundamental operating theory of the proposed method is to cancel the IM3 components of the LNA output signal by generating another IM3 components, which are out-phase with respect to that of the LNA, from the Post IM3 Compensator. A single stage common-source LNA has been designed to verify the linearity improvement of the proposed method through $0.13{\mu}m$ RF CMOS process for WiBro system. The designed LNA achieves +7.8 dBm of input-referred 3^{rd}$-order intercept point (IIP3) with 13.2 dB of Power Gain, 1.3 dB of noise figure and 5.7mA @1.5V power consumption. IIP3 is compared with a conventional single stage common-source LNA, and it shows IIP3 is increased by +12.5 dB without degrading other features such as gain and noise figure.

• Korean Journal of Agricultural Science
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• v.38 no.4
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• pp.625-629
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• 2011

To investigate the protective effect of eggplant (Solanum melongena L.) and its active compound, delphinidin, we used in vitro and cellular system. The active fraction from eggplant, BuOH fraction, showed protective effect from hydrogen peroxide-induced oxidative stress in WI-38 fibroblast cells. It suggests that eggplant would have the protective activity from radical-induced oxidative damage and its BuOH fraction would play the crucial role with antioxidative activity. In addition, delphinidin, the active compound from eggplant, exerted the strong 1,1-diphenyl-2-picrylhydrazyl scavenging effect with $IC_{50}$ value of 6.59 ${\mu}g/mL$. Furthermore, the cellular oxidative stress was induced by 2,2'-azobis (2-amidinopropane) dihydrochloride (AAPH) in LLC-$PK_1$ cells, while treatment of delphinidin atteunated AAPH-induced oxidative stress as dose-dependent manner. The present study suggests the antioxidative activity of eggplant and delphinidin against free radical-induced oxidative stress.

• Journal of the Institute of Convergence Signal Processing
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• v.15 no.3
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• pp.97-103
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• 2014

Recently, digital door locks have been widely used as physical security devices for the door. Although they are convenient compared to the existing lock system, they have the problem of being opened by an electric shock. In this study, to improve safety, a method to hide the door-lock device inside and to display the door-lock on a user's smart-phone screen through the augmented reality is suggested. Furthermore, an additional function has been added which provides memo notes to facilitate communication among family members. The results of this study have been implemented by using motors to control locks, Wi-Fi shield, Arduino, and a virtually created door and showed desirable experimental results.

• Korean Journal of Pharmacognosy
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• v.44 no.3
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• pp.242-252
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• 2013

This study was evaluated to biological activity of breeding lines from Acantopanax( A. sessiliflorus: ASF, A. koreanum: AKN, A. chiicanensis: ACS, A. senticosus: AST) and parts(root, stem, fruit, and leaf) and various extracted solvents( 100% water, 100% EtOH, 50% EtOH). Total polyphenol content of AKN root in 100% water extracts was high detected 464.46 mg/100 g. Total flavonoid content in the leaf was significantly higher than in other parts. The content of total sugars was high in the 50% EtOH extracts and fruit. The major free amino acids were arginine in all extracts. The content of arginine was detected in the root of AKN(1.807 mg/100 mg). Contents of eleutheroside B, E were high detected in 100% water extracts. Antioxidative capacity in the leaves of AKN was the higher than other extracts($EC_{50}=84.8{\mu}g/mL$). The results would be useful for understanding of the physiological properties of AKN extracts.

• Natural Product Sciences
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• v.25 no.3
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• pp.244-247
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• 2019

A new isoprenylated stilbene, flavestinK (1) together with two known isoprenylated stilbenes, flavestin B (2), flavestin G (3), and two isoprenilated flavanones, 4-O-methyl-8-isoprenylnaringenin (4) and 8-isoprenyl-5,7-dihydroxyflavanone (5) were isolated from the leaves of Macaranga recurvata Gage. All of the structures have been determined based on HRESIMS, 1D and 2D NMR spectral data. All of the isolated compounds were evaluated for their cytotoxicity against three human cancer cells (HeLa, T47D and WiDr). Compound 1 showed higher activity than doxorubicin against HeLa cells with $IC_{50}$ value of $13.1{\mu}g/mL$.

• Journal of Mushroom
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• v.12 no.1
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• pp.41-51
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• 2014

Cauliflower mushroom widely known high concent of ${\beta}$-glucan for farm cultivation invigoration verified characteristics of mycelia growth, genetic diversity, resistance to Trichoderma by replacement culture with Trichoderma and growth characteristics of new variety crossbleeding strain. The result of replacement culture with Trichoderma for verification resistance about Trichoderma, 6951 (T. viride) strain did not show special change after formation of confrontation line and 6952 (T. spp.) strain was showed more formation of spore after formation of confrontation line. But 6426 (T. harzianum) strain found to encroach part of growth area of cauliflower mushroom mycelia. Among 10 kinds cauliflower mushroom strain, JF02-06 strain collected by Gurye, found did not spore of Trichoderma and thought to be resistant to Trichoderma. The result of crossbleeding after selected that mother strain good growth and formation of fruit body, verified good mycelia growth at JF02-47, 49 and 50 strain in Korean pine of wood-chip media. The result of gene sequence about ITS1, 5.8S and ITS4 for analysis of genetic diversity at crossbleeding strain, found high significance to other cauliflower mushroom in registered Genebank. The result of growth characteristic of spore and mycelia of cauliflower mushroom by observation microscope, size of spore showed water drop shape to major axis $6{\mu}m$ and minor axis $5{\mu}m$ and clamp showed 3 types in mycelia. The wide of mycelia was $3{\mu}m$. The characteristic of mycelia of cauliflower mushroom found to grow mycelia in clamp at approximately 50%. The growth speed of mycelia was $0.507{\mu}m/min$ and 2nd mycelia grown similar speed to mother mycelia at parallel with mother mycelia after growth speed at $0.082{\mu}m/min$. The formation of clamp made small clamp for 5 hours after shown transfer of electrolyte in mycelia inside. The septum formation started after 3 hours and then finally completed after 2 hours. In this study, strain of cauliflower mushroom verified resistance of Trichoderma, genetic diversity and characteristic of mycelia growth. Therefore, basic knowledge of cauliflower mushroom will improve and further contribute to development of mushroom industry.