• Microbiology and Biotechnology Letters
• /
• v.49 no.2
• /
• pp.210-216
• /
• 2021

This study aimed to enhance ethanol productivity of Saccharomyces cerevisiae through genome editing using CRISPR/CAS9. To increase ethanol productivity, ACC1, ELO1, and OLE1 were overexpressed in S. cerevisiae using the CRISPR/CAS9 system. The strains overexpressing ACC1, ELO1, and OLE1 survived up to 24 h in YPD medium supplemented with 18% ethanol. Moreover, the ethanol yields in strains overexpressing ACC1 (428.18 mg ethanol/g glucose), ELO1 (416.15 mg ethanol/g glucose), and OLE1 (430.55 mg ethanol/g glucose) were higher than those in the control strains (400.26 mg ethanol/g glucose). In conclusion, the overexpression of these genes increased the viability of S. cerevisiae at high ethanol concentrations and the ethanol productivity without suppressing glucose consumption.

• Journal of the Korean Crystal Growth and Crystal Technology
• /
• v.9 no.2
• /
• pp.168-172
• /
• 1999

The 9 $\mu\textrm{m}$ GaN films on sapphire substrate were grown by Hydride vapor phase epitaxy. Dislocation density of these GaN films was measured by TEM. GaN film with crack free and mirror surface was directly grown on sapphire substrate. The dislocation density of this GaN film was $2{\times}10^9/cm^2$. The surface of GaN film on patterned GaN layer also presented a smooth mirror. But a part of GaN surface included holes because of incomplete coalescence. The dislocation density of GaN film above the mask region was lower than that in the window region. Especially, the dislocation density in the region between mask center and window region was close to dislocation free. The average dislocation density of ELO GaN was $8{\times}10^7/cm^2$.

• Proceedings of the KIEE Conference
• /
• 1995.07c
• /
• pp.1025-1027
• /
• 1995

SEG(Selective Epitaxial Growth) and ELO(Epitaxial Lateral Growth) of Silicon offer new opportunities in the fabrication of MEMS(Micro Electro-Mechanical Systems) structures. SEG of silicon enables the stacking of junctions in addition to those resulting from the standard bipolar process and this properly was utilized for the fabrication of an improved-performance color sensor. When the crystalline growth takes place through the seed windows and proceeds over the dielectric, after reaching the surface, it form an ELO silicon layer and this ELO-Si can be modified into various structures for MEMS application such as cantilevers, beams, diaphragms.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
• /
• 2003.07a
• /
• pp.424-427
• /
• 2003

We have investigated the microstructural analysis of epitaxial lateral overgrowth (ELO), pendeoepitaxy (PE), and superlattice structures used as technology for the reduction of structural defects like dislocation in nitride semiconductors using transmission electron microscopy. We confirmed that the regrowth process such as ELO and PE is very effective technique on the reduction of threading dislocation (less than $10^6/cm^2$) in the specific area. However, to decrease the defect density in the whole nitride films and the suppress the generation of defect by regrowth, we should find the optimized conditions. Besides, the process using double PE and AlGaN/GaN superlattice structure showed no effect on the defect reduction up to now.

• The Korean Journal of Applied Statistics
• /
• v.32 no.6
• /
• pp.783-794
• /
• 2019

The current ranking system of the Korean Baduk Association is based on the Elo rating system, which is widely used in the field of chess. Despite the 6.5 point dum (penalty) as compensation for playing as White, many Baduk players still prefer to playing as Black due to Black's higher winning percentage. In this paper, we present the ranking of Baduk players based on the Bradley-Terry model and address the advantage of playing as Black. We compare the ranking from our model with rankings from the Korean Baduk Association.

• Proceedings of the KIPE Conference
• /
• 2000.07a
• /
• pp.600-604
• /
• 2000

In this paper authors proposed a new nonlinear rotor flux observer for rotor field oriented control of an induction motor which is designed based on theory of the extended Luenberger observer(ELO) one of a nonlinear state observer. The proposed rotor flux observer is derived from the 2 phase model of induction motor by the theory of ELO. The simulation results taken under the varying condition of rotor resistance and load torque show fast convergence of estimated rotor flux and high performance of IM drive system is achieved 표 experiment.

• Proceedings of the Korean Vacuum Society Conference
• /
• 2012.02a
• /
• pp.349-349
• /
• 2012

박막형 GaAs 계 III-V 태양전지는 ELO (Epitaxy Lift-off) 기술에 의하여 기판으로부터 분리되어 얻어질 수 있다. 지금까지 이 기술에 대해 개발된 결과에 의하면 박막 III-V 태양전지의 효율이 기존 기판 기반의 태양전지 효율과 비슷한 수준을 얻고 있으며, 기판의 재활용, 플렉서블, 및 신축성 태양전지로의 적용분야 등의 보고들도 발표되고 있어 실리콘 태양전지가 접근하기 힘든 특정한 응용분야로의 가능성을 밝게 해주고 있다. 그러나, 이 ELO방식에 의한 박막형 III-V 태양전지가 실질적으로 상업화 되기 위해서는 생산 수율의 개선 및 기판 재활용 시의 저손실 등 해결해야 할 당면과제들이 놓여 있다. 기판재활용의 가능성을 위해 아직까지 발표된 셀의 크기는 $2{\times}2mm^2$ 이하이며, 보다 넓은 셀에 대하여 기판재활용 방식으로 재생된 효율을 갖는 III-V 박막 태양전지는 보고된 바 없다. 본 연구에서는, $1{\times}1mm^2$, $2{\times}2mm^2$, 그리고 $5{\times}5mm^2$에 대하여 ELO 에 의한 박막 태양전지를 제작해 보고, 보다 넓은 면의 박막 태양전지를 효율적으로 제작하기 위한 방법을 연구하고자 한다. 또한, 이 셀들을 유연한 PDMS transfer에 부착하여 플렉서블 태양전지로의 가능성에 대해서도 기술하고자 한다. 사용된 박막 태양전지 구조는 한국광기술원에서 제작한 22% GaAs 단일 접합 태양전지와 같은 구조로 되어 있으며, 희생층으로는 AlGaAs 층을 사용하였고, ELO을 위한 에칭용 홀 지름은 5, 10, 그리고 $20{\mu}m$에 대하여 조사하였다.

• Proceedings of the Korean Society of Precision Engineering Conference
• /
• 2004.10a
• /
• pp.447-449
• /
• 2004

The purpose of this study is measured surface acoustic wave(SAW) characteristics to confirm utilization possibility as SAW sensor using new Pb(Mg$_{1}$3/Nb$_{2}$3/) $O_3$-PbTiO$_3$ (PMN-PT) piezoelectric substrate. We have tried to see if the material can be practically available as a new surface acoustic wave (SAW) biosensor to detect protein. The experimental results clarified that the frequency filtering of the central frequency of the PMN-PT substrate is a superior result to that of the LiTaO$_3$ (LT) substrate, but the result was not completely satisfactory. We know there is a problem in the design of inter-digital transducer (IDT) pattern. The waves transferred through the input terminal forms SAW which is sure to be transferred to the direction of the output terminal and the backward direction of the input terminal. This reflected wave is reiterated with SAW, which is transferred to the output direction, and so the frequency filtering gives a not good result. The electromechanical coupling coefficient of the PMN-PT substrate is excellent, and we can use it as a SAW sensor, in the near future, provided that there will be a new IDT design to increase the frequency filtering.

• Polymer(Korea)
• /
• v.38 no.6
• /
• pp.726-734
• /
• 2014

Three different types of additives, thiokol, epoxidized natural rubber (ENR) and epoxidized linseed oil (ELO), were dispersed in an epoxy matrix before being used in glass fiber (GF) composites, and their effects on the mechanical and dielectric properties of epoxy resin and glass fiber reinforced epoxy composites (GF/EP) were examined. The addition of each of 7 phr ENR, 9 phr ELO and 5 phr thiokol into the epoxy resin increased the fracture toughness significantly by 56.9, 43.1, and 80.0%, respectively, compared to the unmodified resin. The mode I interlaminar fracture toughness of the GF/EP at propagation was also improved by 26.9, 18.3 and 32.7% when each of 7 phr ENR, 9 phr ELO, and 5 phr thiokol, respectively, was dispersed in the epoxy matrix. Scanning electron microscopy showed that the additives reduced crack growth in the GF/EP, whereas their dielectric measurements showed that all these additives had no additional effect on the real permittivity and loss factor of the GF/EP.

• Proceedings of the KIPE Conference
• /
• 1998.07a
• /
• pp.366-370
• /
• 1998

Indirect vector control for induction motors requires the use of observers for estimation or observation of rotor flux magnitude and position. In this paper, authors discribe the induction motor vector control and introduce a nonlinear observer, named ELO(extended Luenberger Observer), without simulation results as a preliminary work for trial application. Normally, design of nonlinear observer need coordinate transfromation and linearization through solving the partial different equation. However, ELO requires minimal solution of nonlinear partial differential equation. Simulation was performed by under the enviroment of Matlab and Simulink without the proposed observer because we are still working. Simulation was performed with conventional flux observer, a dc-ac inverter by SVPWM technique, a vector controller armed with multiple PI controllers