• Korean Journal of Medicinal Crop Science
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• v.23 no.5
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• pp.379-384
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• 2015

Background : Considerable time and effort is required to develop new Panax ginseng varieties. Ginseng breeders have been developing techniques to shorten the breeding cycle to resolve this problem. In this study, we investigated the effects of adding $GA_3$ and alternating temperature (AT, $2^{\circ}C{\rightarrow}-2^{\circ}C{\rightarrow}2^{\circ}C$) on breaking bud dormancy in the varieties (Chungsun and Sunun) of ginseng root. Methods and Results : The $GA_3$ soaking treatment and AT were applied to one year old roots, which greatly accelerated the emergence of new buds. In one year old roots, new buds emerged from the 4th day post transplanting and after breaking dormancy with $GA_3$ and AT treatments. The emergence of new buds was completed within two weeks. The rate of bud emergence for Chungsun was 60% - 98% over 15 - 60 days after the AT and $GA_3$ treatments. The emergence rate of Sunun was 46% - 92%. Normal growth of the ginseng seedling was observed in spite of the early breaking of bud dormancy by combined $GA_3$ and AT treatments. Conclusions : $GA_3$ and AT treatments shortened the dormancy period and facilitated the stable emergence of ginseng seedlings. However, some plants suffered deformities and early sprouting owing to the combined $GA_3$ and AT treatments. Early sprouting was free from dormancy after leaf fall from the of aerial part of the plant.

• Proceedings of the KIEE Conference
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• 2000.07a
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• pp.350-353
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• 2000

This paper presents an algorithm for Optimal Reactive Power Dispatch(ORPD) problem based on genetic algorithm. Optimal reactive power dispatch is particularized to the minimization of transmission line losses by suitable selection of generator reactive power outputs and transformer tap settings. To reduce system loss and improve voltage profile, two methods, Loss Re-Distribution Algorithm (LRDA) and Voltage Dependent Load Model (VDLM), are applied to ORPD. The proposed methods have been evaluated on the IEEE 30 bus system. Each of results have been compared with result of load flow.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.377-380
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• 2008

In this study, an aerodynamic shape optimization system was developed to study the optimal shape of airfoil. The system consists of GA (Genetic Algorithm) and CFD code based on the Navier-Stokes equation. Lift-drag ratio is chosen as the object function and optimization is conducted for PARSEC airfoil with nine design variables, which is very efficient in representing the surface geometry of airfoil.

• Journal of Institute of Control, Robotics and Systems
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• v.7 no.4
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• pp.319-325
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• 2001

Recently. AGV systems are used to serve the raw material to each work stations automatically. There exists a trade-off between the adequate service supply and the number of purchased AGVs. Also, to reduce the overall production cost, the amount of inventory hold on the shop floor should be considered. In this paper, we present a heuristic technique for determining the number of AGVs which includes the net present fixed costs of each station, each purchased AGV, delivering cost, stock inventory cost, and safety stock inventory cost. Secondly, by using a genetic algorithm, the optimal number of AGVs and the optimal reorder quantity at each station are decided. Lastly, to verify then heuristic algorithm, we have done a computer simulation with different GA parameters.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.19 no.9
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• pp.793-799
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• 2006

In this paper, the gate leakage current is first calculated using the experimental method between gate and drain by opening source electrode. the gate to drain current has been obtained with ground source. The difference between two currents has been tested and proves that the electric field generated by channel charge effect against the image force lowering.

• 한국약용작물학회:학술대회논문집
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• 2008.05a
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• pp.290-291
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• 2008

• Proceedings of the Korean Vacuum Society Conference
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• 2012.08a
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• pp.412-412
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• 2012

갈륨비소(GaAs)는 수직공진표면방출레이저, 발광다이오드, 태양전지 등과 같은 광전소자에 널리 사용되는 물질이다. 그러나 높은 굴절률을 갖는 갈륨비소는 표면에서 30% 이상의 반사율을 갖기 때문에 광손실로 인해 소자의 성능이 저하된다. 따라서 표면 Fresnel 반사율을 낮출 수 있는 효율적인 반사방지막이 필요하다. 최근, 열적 불일치, 물질 선택, 접착력 저하의 단점을 가지고 있는 기존 다중박막을 대체하는 생체모방 서브파장 나노구조가 활발히 연구되고 있다. 이러한 구조는 공기(air)부터 갈륨비소까지 선형적인 유효굴절률 분포를 갖는 유효 단일박막과도 같기 때문에 소자 표면에서의 광손실을 줄일 수 있다. 더욱이, 자연계의 나방의 각막과 나비의 눈의 구조 형태를 모방한 반도체 생체모방 복합 눈(compound eye)은, 즉 마이크로 렌즈모양과 서브파장 나노격자구조의 복합적 형태, 표면에서 우수한 반사방지 특성을 나타낸다. 본 연구에서는, 포토리소그래피와 유도결합플라즈마 식각법을 이용하여 GaAs 기판 표면에 마이크로 렌즈 모양의 패턴을 형성한 후, 스핀코팅을 이용하여 나노 크기를 갖는 실리카 구를 도포하여 건식 식각함으로써 복합 눈 구조를 갖는 갈륨비소 반사방지막을 제작하였다. 제작된 샘플의 표면 및 식각 형상은 전자현미경(scanning electron microscope)을 사용하여 관찰하였으며, UV-vis-NIR spectrophotometer를 사용하여 반사율을 측정하였다.

• New & Renewable Energy
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• v.1 no.2 s.2
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• pp.6-10
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• 2005

[ $CulnSe2$ ]계 화합물은 직접천이형 반도체로 광흡수계수가 매우 높아 박막형 태양전지 제조에 매우 유리하다. 또한 화학적으로 안정하며 Ga, Al 등을 첨가하면 에너지 금지대폭을 조절할 수 있어 Wide Bandgap 태양전지 및 탠덤구조 태양전지를 제조하기에도 용이하다. CIS 물질에서 In을 $20-30\%$ 정도 치환한 $Cu(In,\;Ga)Se_2(CIGS)$ 태양전지의 경우 19.5%의 세계 최고 효율을 보고하고 있으며 이는 다결정 실리콘 태양전지의 효율과 비슷한 수준이다. 본 연구에서는 동시 질공증발법을 이용하여 증착한 CIGS 박막 및 $CuGaSe_2(CGS)$ 박막을 이용하여 태양전지를 제조하였다. 공정의 재현성 및 결정립계가 큰 광흡수층 제조를 위하여 실시간 기판 온도 모니터링 시스템을 도입하였으며 버퍼층으로는 용액성장한 CdS 박막을 사용하였다. SLG/MO/CIGS(CGS)/CdS/ZnO/Al 구조의 태양전지를 제조하여 면적 $0.5cm^2$에서 각각 $17\%(CIGS)$와 $7\%(CGS)$의 효율을 얻었다.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2004.11a
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• pp.252-255
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• 2004

Various Semiconductor/Metal structured nanowires were synthesized from the simple thermal annealing of ball-milled compound powders and the thermal evaporation of metals. Their structural properties were investigated by Scanning Electron Microscopy(SEM) and Transmission Electron Microscopy(TEM), Energy Dispersive X-ray spectroscopy(EDX). Depending on the type of metals and the material of nanowires, uniform somiconductor/metal nanowires(GaN/Al, GaN/Ag) or isolated metal particles on semiconductor nanowires$(SnO_2/Ti,\;Si/Ti)$ were formed on the surface of nanowires.

• Korean Journal of Environmental Agriculture
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• v.35 no.3
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• pp.184-190
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• 2016

BACKGROUND: Anthocyanins, potential health-promoting compounds, were major natural pigment in the blueberry (Vaccinium corymbosum L.). The objectives of this study was to investigate anthocyanin glycosides in the blueberry varieties.METHODS AND RESULTS: A total of seventeen anthocyanins were identified from highbush blueberry using HPLC (representatives, 530 nm) and ESI-MS in positive ion mode. The individual anthocyanins are containing cyanidin, delphinidin, malvidin, peonidin, and petunidin moieties which are acylated with aliphatic acid (acetic acid) and conjugated with sugar moieties (arabinose, galactose, and glucose). Among them, delphinidin 3-O-galactoside (D3Ga), peonidin 3-O-glucoside (Pn3G) + malvidin 3-O-galactoside (M3Ga) were major compounds in varieties. Total anthocyanins were found the highest level in 'Elizabeth' (1,406.3 mg/100 g dry weight) which was 3-fold higher than 'Darrow' (465.7). Especially, D3Ga was presented the 32% of total anthocyanins followed by Pn3G + M3Ga (20%) in 'Elizabeth'.CONCLUSION: This result was showed as valuable information regarding nutritional properties of the different varieties of the highbush blueberry.