• Title/Summary/Keyword: LiGA

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Application of an Optimized Support Vector Regression Algorithm in Short-Term Traffic Flow Prediction

  • Ruibo, Ai;Cheng, Li;Na, Li
    • Journal of Information Processing Systems
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    • v.18 no.6
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    • pp.719-728
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    • 2022
  • The prediction of short-term traffic flow is the theoretical basis of intelligent transportation as well as the key technology in traffic flow induction systems. The research on short-term traffic flow prediction has showed the considerable social value. At present, the support vector regression (SVR) intelligent prediction model that is suitable for small samples has been applied in this domain. Aiming at parameter selection difficulty and prediction accuracy improvement, the artificial bee colony (ABC) is adopted in optimizing SVR parameters, which is referred to as the ABC-SVR algorithm in the paper. The simulation experiments are carried out by comparing the ABC-SVR algorithm with SVR algorithm, and the feasibility of the proposed ABC-SVR algorithm is verified by result analysis. Continuously, the simulation experiments are carried out by comparing the ABC-SVR algorithm with particle swarm optimization SVR (PSO-SVR) algorithm and genetic optimization SVR (GA-SVR) algorithm, and a better optimization effect has been attained by simulation experiments and verified by statistical test. Simultaneously, the simulation experiments are carried out by comparing the ABC-SVR algorithm and wavelet neural network time series (WNN-TS) algorithm, and the prediction accuracy of the proposed ABC-SVR algorithm is improved and satisfactory prediction effects have been obtained.

Study of the Efficiency Droop Phenomena in GaN based LEDs with Different Substrate

  • Yoo, Yang-Seok;Li, Song-Mei;Kim, Je-Hyung;Gong, Su-Hyun;Na, Jong-Ho;Cho, Yong-Hoon
    • Proceedings of the Korean Vacuum Society Conference
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    • 2012.08a
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    • pp.172-173
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    • 2012
  • Currently GaN based LED is known to show high internal or external efficiency at low current range. However, this LED operation occurs at high current range and in this range, a significant performance degradation known as 'efficiency droop' occurs. Auger process, carrier leakage process, field effect due to lattice mismatch and thermal effects have been discussed as the causes of loss of efficiency, and these phenomena are major hindrance in LED performance. In order to investigate the main effects of efficiency loss and overcome such effects, it is essential to obtain relative proportion of measurements of internal quantum efficiency (IQE) and various radiative and nonradiative recombination processes. Also, it is very important to obtain radiative and non-radiative recombination times in LEDs. In this research, we measured the IQE of InGaN/GaN multiple quantum wells (MQWs) LEDs with PSS and Planar substrate using modified ABC equation, and investigated the physical mechanism behind by analyzing the emission energy, full-width half maximum (FWHM) of the emission spectra, and carrier recombination dynamic by time-resolved electroluminescence (TREL) measurement using pulse current generator. The LED layer structures were grown on a c-plane sapphire substrate and the active region consists of five 30 ${\AA}$ thick In0.15Ga0.85N QWs. The dimension of the fabricated LED chip was $800um{\times}300um$. Fig. 1. is shown external quantum efficiency (EQE) of both samples. Peak efficiency of LED with PSS is 92% and peak efficiency of LED with planar substrate is 82%. We also confirm that droop of PSS sample is slightly larger than planar substrate sample. Fig. 2 is shown that analysis of relation between IQE and decay time with increasing current using TREL method.

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A Study on Contact Resistance Reduction in Ni Germanide/Ge using Sb Interlayer

  • Kim, Jeyoung;Li, Meng;Lee, Ga-Won;Oh, Jungwoo;Lee, Hi-Deok
    • JSTS:Journal of Semiconductor Technology and Science
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    • v.16 no.2
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    • pp.210-214
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    • 2016
  • In this paper, the decrease in the contact resistance of Ni germanide/Ge contact was studied as a function of the thickness of the antimony (Sb) interlayer for high performance Ge MOSFETs. Sb layers with various thickness of 2, 5, 8 and 12 nm were deposited by RF-Magnetron sputter on n-type Ge on Si wafers, followed by in situ deposition of 15nm-thick Ni film. The contact resistance of samples with the Sb interlayer was lower than that of the reference sample without the Sb interlayer. We found that the Sb interlayer can lower the contact resistance of Ni germanide/Ge contact but the reduction of contact resistance becomes saturated as the Sb interlayer thickness increases. The proposed method is useful for high performance n-channel Ge MOSFETs.

Thermal Stability Improvement of Ni-Silicide using Ni-Co alloy for Nano-scale CMOSFET (나노급 CMOSFET을 위한 니켈-코발트 합금을 이용한 니켈-실리사이드의 열안정성 개선)

  • Park, Kee-Young;Jung, Soon-Yen;Han, In-Shik;Zhang, Ying-Ying;Zhong, Zhun;Li, Shi-Guang;Lee, Ga-Won;Wang, Jin-Suk;Lee, Hi-Deok
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.21 no.1
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    • pp.18-22
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    • 2008
  • In this paper, the Ni-Co alloy was used for thermal stability estimation comparison with Ni structure. The proposed Ni/Ni-Co structure exhibited wider range of rapid thermal process windows, lower sheet resistance in spite of high temperature annealing up to $700^{\circ}C$ for 30 min, more uniform interface via FE-SEM analysis, NiSi phase peak. Therefore, The proposed Ni/Ni-Co structure is highly promising for highly thermal immune Ni-silicide for nano-scale MOSFET technology.

Protective Constituents Against Sepsis in Mice from the Root Cortex of Paeonia suffruticosa

  • Li, Gao;Seo, Chang-Seob;Lee, Kyeung-Seon;Kim, Hyo-Jin;Chang, Hyun-Wook;Jung, Jun-Sub;Song, Dong-Keun;Son, Jong-Keun
    • Archives of Pharmacal Research
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    • v.27 no.11
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    • pp.1123-1126
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    • 2004
  • The bioassay-guided fractionation of protective agents against sepsis-induced lethality from the root cortex of Paeonia suffruticosa ANDREWS (Ranunculaceae) led to the isolation of eight known compounds: paeonol (1), 2,5-dihydroxy-4-methoxyacetophenone (2), acetovanillone (3), paeonoside (4), paeoniflorin (5), oxypaeoniflorin (6), apiopaeonoside (7), and methyl 3-hydroxy-4-methoxybenzoate (8). Among them, 3 showed the highest survival rate (100% with a dose of 30 mg/kg versus 17% for the control experiment) and reduced alanine aminotransferase level to be a half of the control value on the sepsis model induced by lipopolysaccharide/D-galactosamine.

An Experimental Study on the Transcription Characteristics of Injection-Molded Micro Channel (마이크로채널 전사성 향상을 위한 사출성형공정 최적화 기초연구)

  • Kim, J.S.;Ko, Y.B.;Min, I.K.;Yu, J.W.;Kim, J.D.;Yoon, K.H.;Hwang, C.J.
    • Transactions of Materials Processing
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    • v.15 no.9 s.90
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    • pp.692-696
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    • 2006
  • Micro fabrication of polymeric materials becomes increasingly important. And it is considered as a low-cost alternative to the silicon or glass-based Micro Electro-Mechanical System(MEMS) technologies. In the present study, micro channels were fabricated via LiGA(Lithographie, Galvanoformung, Abformung) process used for Capillary Electrophoresis(CE) chip. Taguchi method was applied to investigate the effects of process conditions in injection molding(melt temperature, injection speed, mold temperature and packing pressure) on the transcription characteristics of the micro channel. It was found that the skin layer disturbs a formation of micro channel. Furthermore, mold temperature and injection speed were two important factors to affect the replication characteristics of micro channel.

한국에 분포하는 한약자원식물의 무기물 함량에 관한 연구 제 2 보 ( The Mineral Content of Medical Wild Plant Resources in Korea ( II ) )

  • 이상래
    • Korean Journal of Plant Resources
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    • v.3 no.2
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    • pp.115-121
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    • 1990
  • In view of the results to have measured metallic elements which is included in 40 sorts of herb medicines and surveyed their distribution, ninekinds of metals including Co, Ce, Ga, 71, Cd, As, Sbr Bu. Pb, are never orlittle included in almost herb medicines. Other twenty four sorts of ele-ments (Mo, Sc, Be, V, Ni, Su, Se, Ba, Cr, Su, Ti, B, Li, Mg, Ca, Sr, Mnl Fe,Cu, Zn. p, Al, Na, K) are metals that are included in large quentities incomparison with others. Selagirellae Radix contains is kinds of metallicelements more then other herb medicines does. The content of elements ofinorganic metal differs greatly according to the part of herb medicines .

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한국에 분포하는 한약자원식물의 무기물 함량에 관한 연구 제1 보 ( The Mineral Content of Medical Wild Plant Resources in Korea ( I ) )

  • 이상래
    • Korean Journal of Plant Resources
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    • v.3 no.2
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    • pp.107-114
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    • 1990
  • In view of the results to have measured metallic elements which is included in 45 sorts of herb medicines and surveyed their distribution, 8 kinds ofmetals including Co, Ge, Ga, TL, Cd, As, 8i, Pb, are never or little includedin almost herb medicines . Other twenty-five sorts of elements (Mo, Sc, Be, V,Ni, Sn, Se, Ba, Cr, Sb, Si, Ti, B, Li, Mg, Ca, Cr, Mn, Fe, Cu, Zn, p, Al, Na,K) are more or Less included in all herb Bedicines ana Na, Ca, p and K aremetals that are included in Large quentities in comrarison with others . Patri-uiae Radix Contains 7 kinds of metal lic elements more than other herb medicinesdoes .

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더덕 ( 사삼 )의 재배방법별 일반성분 및 무기성분에 관한 연구 ( Proximate and Mineral of Dried Wild and Cultivated Codonopsis lanceolata Benth , et Hook , Fil , of Different Cultivated Groups )

  • 신수철
    • Korean Journal of Plant Resources
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    • v.4 no.2
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    • pp.39-45
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    • 1991
  • Proximate compositions of the roots of cultured and wild Codonopsis lanceolata were examined as tile basic reasearch for the study of their source of processed foods.No significant difference in the contents was found between the wild root and thecultivated at 3$0^{\circ}C$ in biotronroom. In view of the results to have measured mineralswhich is included in 14 sorts of Codonopsis lanceolata and surveyed their distribution.12 kinds of minerals including T1, Co, Ge, Sm, Mo, Sc, Be, Cd, As, Ga, Bi, ph are ne-vel or little included in almost source. Other twenty-one sorts of minerals (Ni, Se,Ba, Sb, Si, Ti, B, Li, Ifs, Ca, Sr, Mn, Fe, Cu, Zn, p, Al, Na, V, Cr, K) are more or less in-cluded in all source and Ca, Mg, p, K, and Fe are metals that are included in large qu-entities in comparison with others. No minerals difference in the contents was foundbetween the cultivated temperature. The content of elements of inorganic metal differsaccording to the part of C. lanceolata.

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Manufacturing of Blue Polymer Light Emitting Diodes by Substrate Treatments (기판처리에 따른 청색 고분자 유기발광다이오드(PLED)의 제작)

  • Shin, Sang-Baie;Yoo, Jae-Heuk;Gong, Su-Cheol;Chang, Ji-Geun;Chang, Ho-Jung;Chang, Young-Cheol
    • Proceedings of the KAIS Fall Conference
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    • 2006.11a
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    • pp.133-134
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    • 2006
  • 본 논문에서는 ITO/Glass 기판에 스핀 코팅법(Spin Coating)과 열 증착법(Thermal Evaporation)을 이용하여 ITO/PEDOT:PSS/PVK/PFO-poss/Li/Al 구조를 갖는 청색 고분자 유기전계발광소자를 제작하였다. 청색 고분자 유기발광다이오드 제작시 ITO 전극을 $O_2$ gas를 이용한 Plasma Treatment와 Heat Treatment를 실시하여 기판처리가 제작된 소자의 전기, 광학적 특성에 미치는 영향에 대하여 조사하였다. Plasma와 Heat Treatment를 동시에 처리한 소자에서 가장 우수한 전기, 광학적 특성을 나타냈으며, 기판처리를 하지 않은 경우는 전기, 광학적 특성은 크게 감소하였다.

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