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Compound-Type Hybrid Energy Storage System and Its Mode Control Strategy for Electric Vehicles

  • Wang, Bin;Xu, Jun;Cao, Binggang;Li, Qiyu;Yang, Qingxia
    • Journal of Power Electronics
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    • v.15 no.3
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    • pp.849-859
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    • 2015
  • This paper proposes a novel compound-type hybrid energy storage system (HESS) that inherits the unique advantages of both battery/supercapacitor (SC) and the SC/battery HESSs for electric vehicles (EVs). Eight operation modes are designed to match this system. A mode control strategy is developed for this HESS on the basis of these modes, and five classes of operation modes are established to simplify this strategy. The mode control strategy focuses on high operating efficiency and high power output. Furthermore, the compound-type HESS is designed such that the SC is the main priority in braking energy absorption. Thus, this HESS can operate efficiently and extend battery life. Simulation results also show that the compound-type HESS can not only supply adequate power to the motor inverter but can also determine suitable operation modes in corresponding conditions. Experimental results demonstrate that this HESS can extend battery life as well. The overall efficiency of the compound-type HESS is higher than those of the battery/SC and the SC/battery HESSs.

Antimicrobial Effects of Ocotillone Isolated from Stem Bark of Ailanthus altisshima

  • Lee, Dong-Gun;Chang, Young-Su;Park, Yoon-Kyung;Hahm, Kyung-Soo;Woo, Eun-Rhan
    • Journal of Microbiology and Biotechnology
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    • v.12 no.5
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    • pp.854-857
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    • 2002
  • Bioassay-directed chromatographic fractionation of a methylene chloride extract of Ailanthus altisshima indicated the presence of 20(S), 24(R), epoxy-25-hydroxydammarane-3-one (compound 1, ocotillone) which was isolated from this plant, for the first time. Antimicrobial activity of compound 1 was measured by inhibition of bacterial and fungal cells growth and by a hemolytic assay with human erythrocytes, respectively. The results revealed that compound 1 had potent antibacterial activity against Cram-negative bacteria, P. aeruginosa and S. typhimurium, that were without hemolytic activity, whereas it had weak antimicrobial activity against Gram-positive bacteria and fungi. These results demonstrated that the compound 1 has more antibacterial activity against 6ram-negative bacteria, which have no hemolytic activity, than Gram-positive bacteria and fungi. This is the first report on the biological activities of the compound 1.

Isolation and Characterization of α-Glucosidase Inhibitor Produced by Bacillus sp. SKU31-1 Strain (Bacillus sp. SKU31-1가 생산하는 α-Glucosidase 저해제 분리 및 특성 조사)

  • Kim, Shin-Duk
    • Korean Journal of Microbiology
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    • v.50 no.4
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    • pp.381-383
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    • 2014
  • In the course of screening for ${\alpha}$-glucosidase inhibitor produced by microorganism, the active compound was isolated from the culture filtrate of Bacillus sp. SKU31-1 using a series of chromatography procedures. The structure of the active compound was elucidated as 5-amino-1-hydroxymethyl-1, 2, 3, 4-cyclohexanetetrol on the basis of spectroscopic evidence obtained and comparison with data from the literature. The active compound showed potent inhibitory activity against ${\alpha}$-glucosidase with an $IC_{50}$ value of $1.9{\mu}M$ for maltose and 4.9 mM for sucrose. A Lineweaver-Burk plot indicated that its inhibition of ${\alpha}$-glucosidase was competitive, with a $K_i$ value of 0.15 mM.

Analysis of Beauvericin and Unusual Enniatins Co-Produced by Fusarium oxysporum FB1501 (KFCC 11363P)

  • Song Hyuk-Hwan;Ahn Joong-Hoon;Lim Yoong-Ho;Lee Chan
    • Journal of Microbiology and Biotechnology
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    • v.16 no.7
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    • pp.1111-1119
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    • 2006
  • Beauvericins and enniatins are cyclohexadepsipeptides exhibiting various biological activities on animal systems, including humans. Fusarium oxysporum FB1501 (KFCC 11363P) that produces four different cyclohexadepsipeptides was isolated from soil in Korea and the structures of the four cyclohexadepsipeptides elucidated by HPLC, MS, IR, and NMR analyses. The molecular weights for compounds 1,2,3, and 4 were determined to be 654.5, 784.5, 668.6, and 682.5, respectively, on the basis of ESI-MS measurements. The IR spectra for all the compounds exhibited absorptions for ester $(1,733-1,743\;cm^{-1})$ and amide $(1,649-1,655\;cm^{-1})$ bonds that were very similar to those for beauvericin and enniatins with ester and amide absorptions. The results of the NMR analysis $(^{1}H,\;^{13}C,\;135-DEPT,\;COSY,\;HMQC,\;and\;HMBC;\;in\;COCl_{3})$ revealed that compounds 1,3, and 4 consisted of $_{L}-N-methyl\;valine$ (N-MeVal), $_{D}-{\alpha}-hydroxyisovaleic\;acid$ (Hiv), and 2-hydroxy-3-methylpentanoic acid (Hmp) residues (compound 1: three N-MeVal residues, two Hiv residues, and one Hmp residue; compound 3: three N-MeVal residues, one Hiv, and two Hmp residues; compound 4: three N-MeVal residues and three Hmp residues). Therefore, the compounds were identified as enniatin H (compound 1), enniatin I (compound 3), and enniatin MK1688 (compound 4). Compound 2 was analyzed as beauvericin according to 1D and 2D NMR analyses. This study is the first report related to the co-production of beauvericin with other unusual enniatins, such as enniatin H, enniatin I, and enniatin MK1688, by Fusarium oxysporum.

Separation and Identification of a Growth Inhibiting Compound from Aralia continentalis (독활(Aralia continentalis)로부터 생장억제물질(生長抑制物質)의 분리(分離) 및 동정(同定))

  • Kim, K.U.;Back, K.W.
    • Korean Journal of Weed Science
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    • v.10 no.3
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    • pp.221-226
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    • 1990
  • This experiment was performed to identify and isolate a growth inhibiting compound from Aralia continentalis. In order to isolate the growth inhibiting compound from Aralia continentalis the bioassay test of lettuce seed germination and rice seedling growth were used. Through these bioassays the growth inhibiting compound which was spotted at $R_f$ 0.51 on Tlc was isolated. This compound inhibited the lettuce growth by 79% at the concentration of 1000ppm. When sprayed with $FeCl_3$ reagent, it developed a bule spot. It had UV-absorbance at 217 nm and 342 nm, and $OH^-$ of $3600cm^{-1}$, C=O of $1700cm^{-1}$, C=C of $1600cm^{-1}$, and C-O of $1200cm^{-1}$ on IR spectrum. Through HPLC analysis this compound was identified as a ferulic acid ($C_{10}H_{10}O_4$) having 25 min. retention time.

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Differential Dyeing Technology in Wool (양모의 이색효과 염색방법)

  • Chang, Bo-Hyun;Lee, Hak-Ki
    • Textile Coloration and Finishing
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    • v.4 no.1
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    • pp.10-15
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    • 1992
  • Differential dyeing technologies for wool are discussed in one bath dyeing of cationic compound treated wool and untreated wool. By increasing the concentration of cationic compound to wool the k/s value of wool and the color difference (ΔE) between treated and untreated one become higher in one bath dyeing. The proper concentration of cationic compound to wool was 2% in one bath dyeing since the dyeing fastness became lower according to the increase of the concentration.

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Cirsiumaldehyde from Gastrodia elata

  • YunChoi, Hye-Sook;Pyo, Mi-Kyung;Park, Kyung-Mi
    • Natural Product Sciences
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    • v.3 no.2
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    • pp.104-105
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    • 1997
  • In the course of continous work on tubers of Gastrodia elata, a new constituent was isolated from the ethyl acetate soluble fraction prepared from the methanol extract. The structure of the compound was identified as ${\alpha},{\alpha}'-[bis-2-(5-carboxaldehydo)furanyl]-dimethyl$ ether from the elemental analytical and spectroscopic data. This compound was once isolated from Cirsium chlorolepis and named as cirsiumaldehyde. This is the first furan type compound isolated from Gastrodia elata.

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A compound Poisson risk model with variable premium rate

  • Song, Mi Jung;Kim, Jongwoo;Lee, Jiyeon
    • Journal of the Korean Data and Information Science Society
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    • v.23 no.6
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    • pp.1289-1297
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    • 2012
  • We consider a general compound Poisson risk model in which the premium rate is surplus dependent. We analyze the joint distribution of the surplus immediately before ruin, the deffcit at ruin and the time of ruin by solving the integro-differential equation for the Gerber-Shiu discounted penalty function.

Monolithic X-band Mixer (모노리식 X-band 혼합기)

  • Jun, Yong-Il;Park, Hyung-Moo;Ma, Dong-Sung
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.426-429
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    • 1988
  • A simple design method of a single balanced MMIC mixer is described. It uses small signal S11 and capacitive load for the input matching circuit and the output loading circuit, respectively. It is found that the conversion gain of the FET mixer is independent of FET gate width. The fabricated mixer has 2.5 dB conversion gain at 9 GHz with 50 ohm IF load and 2 dBm local oscillator power.

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