• Journal of Microbiology and Biotechnology
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• v.29 no.6
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• pp.999-1007
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• 2019

Middle East respiratory syndrome coronavirus (MERS-CoV) was first identified in Saudi Arabia in 2012 and related infection cases have been reported in over 20 countries. Roughly 10,000 human cases have so far been reported in total with fatality rates at up to 40%. The majority of cases have occurred in Saudi Arabia with mostly sporadic outbreaks outside the country except for the one in South Korea in 2015. The Korean MERS-CoV strain was isolated from the second Korean patient and its genome was fully sequenced and deposited. To develop virus-specific protective and therapeutic agents against the Korean isolate and to investigate molecular determinants of virus-host interactions, it is of paramount importance to generate its full-length cDNA. Here we report that two full-length cDNAs from a Korean patient-isolated MERS-CoV strain were generated by a combination of conventional cloning techniques and efficient Gibson assembly reactions. The full-length cDNAs were validated by restriction analysis and their sequence was verified by Sanger method. The resulting cDNA was efficiently transcribed in vitro and the T7 promoter-driven expression was robust. The resulting reverse genetic system will add to the published list of MERS-CoV cDNAs and facilitate the development of Korean isolate-specific antiviral measures.

• Journal of the Korean Society of Fisheries and Ocean Technology
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• v.19 no.2
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• pp.125-129
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• 1983

It is customary to assume that the resistance of a jull at uniform speed may be regarded as the sum of viscous and wavemaking component resistance, or C sub(i)=C sub(v)+C sub(w), where C sub(v) is regarded as a function of Reynolds Number R and C sub(w) a function of Froude Number F. Formulae have been obtained for ∂C sub(w)/∂R, ∂C sub(v)/∂F which may be relevant in seeking theoretical grounds for possible interaction between viscous and wavemaking component resistances. The values of ∂C sub(w)/∂R are small. In general they are smaller than corresponding values of ∂C sub(v)/∂R. But although these values are small it does not follow that they are entirely negligible. The Froude assumption that the rate of change of C sub(w) with R is zero must bel regarded as incorrect.

• Journal of the Institute of Electronics Engineers of Korea SD
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• v.42 no.6 s.336
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• pp.23-30
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• 2005

In this paper, OPPS(oxidized porous poly-silicon) field emitters were fabricated by using various emitter-electrode metal and these electron emission characteristics were investigated for different thermal annealing effects. The addressed OPPS field emitter with Pt/Ti emitter electrode annealed at $300^{\circ}C$-1hr showed the efficiency of $2.98\%$ at $V_{ps}$=12 V and one annealed at $350^{\circ}C$-1hr showed the highest efficiency of $3.37\%$at $V_{ps}$=16V. They are resulted from the improvement of interfacial contact characteristics of thin emitter metal to an oxidized porous poly-silicon and the decrease of electrical resistance of emitter metal. The brightness of the OPPS field emitter increases linearly in $V_{ps}$ and after oxidation process for $900^{\circ}C$-50min, the brightness of the OPPS field emitter with the as-deposited Pt/Ti emitter electrode was 3600 cd/$m^2$ at the $V_{ps}$=15 V, 6260 cd/$m^2$ at the $V_{ps}$=20 V. Thermal treatment improved the adhesion between the Ti buffer layer and the oxidized porous poly-silicon and also played an important role in the uniform distribution of electric field to the emitter electrode.

• Journal of the Microelectronics and Packaging Society
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• v.10 no.1
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• pp.65-69
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• 2003

Microstructural and electromagnetic properties of YIG ferrites, (Y, Ca)-(Fe, V, In, Al)-O for Isolator/Circulator were investigated with the sintering temperature. YIG ferrites of $Y_{2.1}Ca_{0.9}Fe_{4.4}V_{0.5}In_{0.05}Al_{0.05}O_{12}$ were fabricated by sintering at $1300^{\circ}C$, $1330^{\circ}C$, $1350^{\circ}C$, $1370^{\circ}C$. Crystallographic and microstructural properties were measured using XRD and SEM. Saturation magnetization$(4{\pi}M_s)$ were measured using VSM, and FMR(Ferromagnetic Resonance) experiment was conducted to measure ferromagnetic resonance line width$({\Delta}H)$. Microwave characteristics of YIG ferrites were measured using a Network Analyzer. The YIG ferrite of $Y_{2.1}Ca_{0.9}Fe_{4.4}V_{0.5}In_{0.05}Al_{0.05}O_{12}$, sintered at $1350^{\circ}C$, showed higher density, saturation magnetization and lower ferromagnetic resonance line width than those sintered at any other temperature.

• Journal of the Korean Vacuum Society
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• v.6 no.1
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• pp.36-43
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• 1997

FECAPS(ferroelectric capacitors) have been fabricated by RF magnetron sputtering deposition of 3000$\AA$ PZT thin films on the Pt/Ti/$SiO_2$/Si substrates and post-annealing with the temperature of $550^{\circ}C$~$650^{\circ}C$ for 10 sec~50 sec in a RTA system. The electrical characteristics of the fabricated capacitors showed the highest dielectric constant and remanent polarization[${\varepsilon_r(1kHz)$=690, $2P_r$(-5V~5V sweep)=22$\mu$C/$ \textrm{cm}^2$] in the samples annealed at $650^{\circ}C$ for 30 sec, while the lowest tangent loss and leakage current [$tan\delta(\ge10kHz)\le0.02, \; J_i(5V)=3\mu\textrm{A}/\textrm{cm}^2$]in the samples annealed at $600^{\circ}C$ for 30 sec.

• Journal of Sensor Science and Technology
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• v.18 no.3
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• pp.222-225
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• 2009

This paper describes the fabrication and characteristics of Schottky micro hydrogen sensors for high temperatures by using polycrystalline(poly) 3C-SiC thin films grown on Si substrates with thermal oxide layer using APCVD. Pd/poly 3C-SiC Schottky diodes were made and evaluated by I-V and C-V measurements. Electric current density and barrier height voltage were $2{\times}10^{-3}A/cm^2$ and 0.58 eV, respectively. These devices could operate stably at about 400 $^{\circ}$. The characteristics of implemented sensors have been investigated in terms of sensitivity, linearity of response, response rate, and response time. Therefore, from these results, Pd/poly 3C-SiC Schottky devices have very high potential for high temperature $H_2$ sensor applications.

• Journal of Microbiology and Biotechnology
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• v.16 no.7
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• pp.1120-1124
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• 2006

Supplementation with rice oil and its major components (oleic acid and linoleic acid) was found to have a significant influence on cephalosporin C (CPC) production and cell growth by A. chrysogenum M35 in shake flask cultures. Five percent (v/v) rice oil had the most robust effect and 5% (v/v) oleic acid was the second most efficient on cell growth, whereas 3% (v/v) linoleic acid was found to be optimal for CPC production. Rice oil, oleic acid, and linoleic acid also significantly improved the rates of glucose consumption. When glucose was almost consumed, CPC production was initiated and, on the addition of rice oil, lipase activity increased steadily to 1.56 U/ml for 4 days. These results suggest that rice oil and fatty acids are used as carbon source to produce CPC by A. chrysogenum M35. Moreover, a mixture, composed of 40% (v/v) oleic acid and 60% (v/v) linoleic acid, had the strongest stimulatory effect on CPC production, due to a synergistic effect of the two fatty acids. Consequently, the maximum CPC titer (7.44 g/l) was improved about 4.5-fold.

• Journal of Korean Society of Transportation
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• v.20 no.5
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• pp.217-230
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• 2002

본 연구는 민감도 분석을 통한 다지교차로의 효용성 분석 연구로 신호교차로, Roundabout, 그리고 Modern Roundabout의 특성을 고찰하고 교통류의 특성에 따른 민감도 분석을 통한 교차로 형태를 검토하는 것에 그 목적을 두고 있다. 이를 위해, 첫째, 신호교차로와 Roundabout의 특성과 사례를 고찰하였다. 둘째, 4지교차로와 5지교차로의 교통류 특성별로 교통량을 산정하여, TSIS Tool을 이용한 분석을 통해 교통류 특성별 신호 교차로와 Round about의 민감도를 비교하였다. 셋째, 민감도 비교를 통한 교통류 특성별 효율적인 교차로 형태를 도출하였다. 4지교차로의 경우, 첫째, 일반적으로 V/C비의 변화에 대해 V/C비가 0.7이하일 때는 Roundabout가 V/C비가 0.7을 초과할 때는 신호교차로가 효율적인 것으로 나타났다. 둘째, V/C비별 회전교통량의 변화와 회전교통량 변화별 V/C비 변화에서도 V/C비의 변화의 분석결과와 비슷한 양상을 보였다. 5지교차로의 경우, 첫째, 4지교차로와는 달리 전반적으로 신호교차로 보다는 Roundabout가 더 효율적인 교차로 형태로 나타났다. 둘째, V/C비별 회전교통량의 변화와 회전교통량 변화별 V/C비 변화에서는 V/C비가 0.8을 초과하고 우회전교통량비가 30%∼40%인 경우에 신호교차로가 조금 더 효율적인 것으로 나타났다.

• Korean Journal of Food Science and Technology
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• v.14 no.3
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• pp.257-264
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• 1982

In the present stud changes of some chemical and physical properties of a soybean oil, aerated at 120 ml/min through a porous gas distributor and oxidized at $45^{\circ}C{\sim}180^{\circ}C$, was investigated. The results of the study were as follows: The peroxide, thiobarbituric acid, and iodine value of the soybean oil which was aerated at 120 ml/min increased rapidly as oxidation temperature exceeded over $80^{\circ}C$. The acid value of the oil increased very rapidly as the oxidation temperature passed over $160^{\circ}C$. The content of the unsaturated fatty acid of the oil decreased considerably as the oxidation temperature exceeded over $80^{\circ}C$, whereas that of the saturated fatty acid did not change appreciably. This related well to the changes of the iodine value of the oil subjected to the same experimental conditions. The viscosity and refractive index of the oil increased rapidly as the oxidation temperature passed over $180^{\circ}C$. The following linear relationship hold for the viscosity and refractive index of the oil in the present study. $$V=Aexp({\frac{E}{RT}})$$ where V=viscosity(poise), A=constant, E=activation energy for viscous flow, R=gas constant, T=oxidation temperature$(^{\circ}K)$. The following relationship also hold for the viscosity and refractive index$({n^{20}}_D)$ of the oil at the present experimental conditions. $${n^{20}}_D=1.4614+7.333{\times}10^{-5}t+2.9612{\times}10^{-3}\;InV$$ where t=temperature$(^{\circ}C)$ at which the viscosity was measured.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.7
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• pp.662-666
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• 2006

Microstructure and electrical properties of ZnO varistors as a function of sintering temperature and times were investigated. Sintering temperature and times greatly affected electrical properties and Bi-rich liquid phase of the microstructure. The varistor which were sintered at $1125^{\circ}C\sim1150^{\circ}C$, for 2 hr exhibited the varistor voltage$(V_c)$, nonlinear coefficient $(V_{10mA}/V_{1mA})$, leakage current$(I_L)$ dielectric constant and dissipation factor as $225\sim250V/mm,\;0.89\sim0.92,\;0.8\sim1.1{\mu}A,\;720\sim740\;and\;1.8\sim2.0%$, respectively.