• Journal of Microbiology and Biotechnology
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• v.20 no.3
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• pp.510-512
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• 2010

A series of thiobarbituric acid derivatives were constructed and evaluated for inhibitory activity on hepatitis C virus NS5B polymerase. In biochemical assays using purified viral polymerase and RNA template, the $IC_{50}$ value was improved to 0.41 ${\mu}M$ from the original compound's 1.7 ${\mu}M$ value. In HCV sub genomic replicon assay, the $EC_{50}$ value was improved to 3.7 ${\mu}M$ from the original compound's 12.3 ${\mu}M$ value. $CC_{50}$ was higher than 77 ${\mu}M$ for all compounds tested, suggesting that they are useful candidates for anti-HCV therapy.

• Composites Research
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• v.25 no.5
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• pp.141-146
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• 2012

The strength design for the lightweight bicycle wheel made of the Carbon/Epoxy composite laminates has been discussed in this paper. For bicycle wheel design, lightness of the wheel is important. Also, it has to satisfy the required strength under specific loading cases. Two testing methods for the bicycle wheel, i.e. vertical and complex loadings, are adopted in this study. Because the strengths of composite wheel is different in relation to the stacking sequence and the number of plies, it is important to decide an appropriate stacking sequence and number of layers for the composite wheel. From the finite element analysis results, the most stable sequence orientation and number of layers are determined. The stacking sequence $[0]_{8n}$, $[90]_{8n}$, $[0/90]_{2ns}$, $[{\pm}45]_{2ns}$, $[0/{\pm}45/90]_{ns}$ (n=1,2,3,4)are performed for finite element analysis. From results, $[0/{\pm}45/90]_{3s}$ lay-up is a good selection for the composite bicycle wheel. Also, the weakest point and layer are found in this study.

• Journal of Acupuncture Research
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• v.30 no.5
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• pp.25-39
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• 2013

Objectives : This study was designed to find out the differences of the acupuncture sensation by type of pharmacopuncture. And furthermore we try to find out whether normal saline(NS) is able to be constituted as an appropriate control group for the Calculus Bovis Fel Ursi Moschus(BUM) pharmacopuncture, mountain ginseng pharmacopuncture and sciatica no. 5 pharmacopuncture. Methods : NS and three type of pharmacopunctures were inserted into $ST_{36}$, and $ST_{37}$ of the subjects. Before and after the treatment, subjects completed a questionnaire rating the intensity of 13 kinds of acupuncture sensation(acupuncture sensation scale, ASS). We compared the subjective acupuncture sensation between the NS and three type of pharmacopunctures. Results : BUM pharmacopuncture showed significantly intense acupuncture sensation comparing other two pharmacopunctures and NS. There was no statistically significant difference among mountain ginseng pharmacopuncture, sciatica no. 5 pharmacopuncture and NS. Conclusions : We found that NS may be able to be an placebo pharmacopuncture for mountain ginseng pharmacopuncture and sciatica no. 5 pharmacopuncture. Additional study is needed for placebo pharmacopuncture of BUM pharmacopuncture.

• Journal of the Korean Institute of Telematics and Electronics
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• v.20 no.5
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• pp.43-49
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• 1983

In this paper, an architecture for high-speed RNS multiplier were proposed by using com-binational logic circuit. The optimum conditions of moduli set which could be saved hardware and operation time were also considered. In the case of RRNS multiplier, output translation could be achieved effectively by means of the modified CRT with magnitude index. It is shown that the estimated multiplication time is about 31.7 ns in NRNS, whereas 47.95 ns in RRNS, respectively.

• The KIPS Transactions:PartA
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• v.14A no.4
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• pp.203-208
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• 2007

This paper proposes a $64{\times}64$ Modified Booth multiplier using CMOS multi-valued logic circuits. The multiplier based on the radix-4 algorithm is designed with current mode CMOS quaternary logic circuits. Designed multiplier is reduced the transistor count by 64.4% compared with the voltage mode binary multiplier. The multiplier is designed with Samsung $0.35{\mu}m$ standard CMOS process at a 3.3V supply voltage and unit current $5{\mu}m$. The validity and effectiveness are verified through the HSPICE simulation. The voltage mode binary multiplier is achieved the occupied area of $7.5{\times}9.4mm^2$, the maximum propagation delay time of 9.8ns and the average power consumption of 45.2mW. This multiplier is achieved the maximum propagation delay time of 11.9ns and the average power consumption of 49.7mW. The designed multiplier is reduced the occupied area by 42.5% compared with the voltage mode binary multiplier.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.47 no.5
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• pp.556-561
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• 2014

We applied a combination of most probable number-polymerase chain reaction (MPN-PCR) methods using a PCR procedure targeting the H-NS (VP1133) gene to detect Vibrio parahaemolyticus presence and density in seawater as well as within short-necked clam Ruditapes philippinarum tissues collected from Gomso Bay, Korea. In 30 seawater samples, V. parahaemolyticus levels ranged from less than 1.8 to $1.1{\times}10^3MPN/100mL$, and samples from August showed higher than those from other months. Furthermore, the levels of V. parahaemolyticus in six short-necked clam samples ranged from $7.8{\times}10^2$ to $2.1{\times}10^3MPN/100g$, approximately 2.5 times higher than in seawater samples from the corresponding month. Our results provide data on V. parahaemolyticus contamination in seawater and short-necked clam tissues, and help to improve quantitative methods of assessing V. parahaemolytcius levels.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.19 no.2
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• pp.174-180
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• 2008

The pulsed amplifier which switches the main supply voltage of RF amplifier according to input pulse signal has good efficiency and low noise level between pulses. And it has simple structure because it doesn't need a pulse modulator at input port. The pulsed amplifier using the conventional switching circuit has slow fall time compared to rise time. We proposed the novel switching circuit for improving the fall time of pulsed amplifier The proposed switching circuit is implemented by replacing FET of conventional circuit with BJT. As a result of appling this circuit to RF pulsed amplifier, the rise and fall time are 5.7 ns and 21.9 ns at 27 dBm output power, respectively.

• Journal of Astronomy and Space Sciences
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• v.22 no.4
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• pp.491-500
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• 2005

Every time laboratory in the world follows an international standard time scale and GPS (Global Positioning System) is playing an important role. Korea Research Institute of Standards and Science is also operating a permanent GPS station for time transfer. To improve the accuracy and precision of the clock offsets derived from GPS we used carrier phase measurements. In addition, we tested four different kinds of GPS satellite orbits and compared the results. The precision of the time offsets using rapid and ultra-rapid orbits was about 0.5 nanoseconds (ns). Tn the case of broadcast orbits, the precision was better than 2 ns.

• Advances in concrete construction
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• v.10 no.5
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• pp.403-416
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• 2020

This study investigated the effect of alkaline activators - NaOH_aq (NH) (NH: 0-16 M) and Na₂SiO_3aq (NS) (NS/NH: 0-3.5) in the synthesis of silico-manganese fume (SMF) and ground blast furnace slag (BFS) blended alkali-activated mortar (AASB). The use of individual activator was ineffective in producing AASB of sufficient fresh and hardened properties, compared to the synergy of both activators. This may be attributed to incomplete dissolution and condensation of oligomers required for gelation of the binder. An inverse relationship was noted among the fresh properties and the NH concentration or NS/NH ratio. This was influenced by the dissolution and condensation of silicate monomers under polymerization process. The maximum 28-day strength of ~45 MPa, setting time of 60 min and flow of 182 mm was obtained with the use of combined activators (10M-NH and NS/NH=2.5). The combined activators at NS/10M-NH=2.5 constituted SiO₂/Na₂O, H₂O/Na₂O and H₂O/SiO₂ molar ratio of 1.61, 17.33 and 10.77, respectively. This facilitated the formation of C-S-H, C/K-A-S-H and C-Mn-S-H in the framework together with an increase in the crystallinity due to more silicate re-organization within the aluminosilicate chain. On comparison of the high concentrated with mild alkali synthesized product, it revealed that the concentration of OH^- and Si monomers together with alkali metals influenced the dissolution of precursors and embedment of the constituent elements in the polymeric matrix. These factors eventually contributed to the microstructural densification of the mortar prepared with NS/10M-NH=2.5 thereby enhancing the compressive strength.

• Proceedings of the IEEK Conference
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• 2004.06b
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• pp.367-370
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• 2004

We fabricated PLT(5) thin film on $Pt/TiO_x/SiO_2/Si$ substrate by using sol-gel method and investigated leakage current, switching and retention properties. The leakage current density of PLT(5) thin film was $3.56{\times}10^{-7}A/cm^2$ at 4V. In the examination of switching properties, pulse voltage and load resistance were $2V{\~}5V$ and $50{\Omega}{\~}3.3k{\Omega}$, respectively. Switching time had a tendency to decrease from 520ns to 140ns with the increase of pulse voltage, and also the time was increased from 140ns to $13.7{\mu}s$ with the increase of load resistance. The activation energy obtained from the relation of applied pulse voltage and switching time was about 143kV/cm. The error of switched charge density between hysteresis loop and experiment of polarization switching was about $10\%$. Also, polarization in retention was decreased as much as about $8\%$ after $10^5$s.