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A Study on the Equivalent Circuit and Parameter Estimation of I.M for Steady state. (정상상태시 유도전동기의 등가회로 및 정수산정에 관한 연구)

  • Baek, Soo-Hyun;Kim, Yong
    • Proceedings of the KIEE Conference
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    • 1988.07a
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    • pp.80-82
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    • 1988
  • This paper proposed a new equivalent circuit and parameter estimation for I.M, which is different from T type and L type equivalent circuits. By using this circuit, we can analyze the torque of I.M, such as seperately exited D.C Motor, further more, we think that this equivalent circuit is effective to the vector control system for I.M.

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Reduction of Nitro and Nitroso Compounds by Glucose and Baker's Yeast (Glucose와 Baker's Yeast에 의한 니트로와 니트로소 화합물의 환원반응)

  • 김경순;박종옥류병호최희숙
    • KSBB Journal
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    • v.11 no.6
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    • pp.623-629
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    • 1996
  • m-Bromonitrobenzene was reduced to m-bromoaniline with a 86∼91% yield by either baker's yeast (Sigma type I) or glucose and baker's yeast in conjunction with glucose. Nitrosobenzene was reduced to aniline in good yields using baker's yeast(Sigma type I) only.

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ON STABILITY OF A GENERALIZED QUADRATIC FUNCTIONAL EQUATION WITH n-VARIABLES AND m-COMBINATIONS IN QUASI-𝛽-NORMED SPACES

  • Koh, Heejeong;Lee, Yonghoon
    • Journal of the Chungcheong Mathematical Society
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    • v.33 no.3
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    • pp.319-326
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    • 2020
  • In this paper, we establish a general solution of the following functional equation $$mf\({\sum\limits_{k=1}^{n}}x_k\)+{\sum\limits_{t=1}^{m}}f\({\sum\limits_{k=1}^{n-i_t}}x_k-{\sum\limits_{k=n-i_t+1}^{n}}x_k\)=2{\sum\limits_{t=1}^{m}}\(f\({\sum\limits_{k=1}^{n-i_t}}x_k\)+f\({\sum\limits_{k=n-i_t+1}^{n}}x_k\)\)$$ where m, n, t, it ∈ ℕ such that 1 ≤ t ≤ m < n. Also, we study Hyers-Ulam-Rassias stability for the generalized quadratic functional equation with n-variables and m-combinations form in quasi-𝛽-normed spaces and then we investigate its application.

Introduction of the M(i,j,k)BCP and Risk Assessment of Underground Limestone Mine (재난관리체계(M(i,j,k)BCP) 제안과 석회석광산의 리스크 평가)

  • Lee, Seong Min;Kim, Sun-Myung;Lee, Yeon Hee
    • Tunnel and Underground Space
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    • v.22 no.6
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    • pp.383-392
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    • 2012
  • This study introduces $M_{(i,j,k)}BCP$ (Mining Business Continuity Planning) which is the smart management system of mine disasters to achieve the safe and eco-friendly mining. Where, 'i' is mine kinds, 'j' is mining processes, and 'k' is risks at process respectively. By specifically setting 'i=1=limestone mine', this study also suggests that $M_{(i,j,k)}BCP$ is the smart management system of limestone mine. Mining risks used in this study were obtained from professional survey and literature review. This study classified these risks by five different mining processes and reduced risk numbers approximately 60 to 26. And they were all allocated into $M_{(i,j,k)}BCP$ and assessed. To do assess risks, this study used four risk indexes which are probability, casualty, facility loss, and discontinuity respectively. By the results of the assessment of risks, results could be four specific groups based on their causes and impacts. In addition, one of the results showed that the most possible risks at limestone mine was the roof-fall and rock-fall in digging process. This result means that $M_{(1,2,1)}BCP$ should be established as a first priority at limestone mine.

The Activity Changes and Properties of ${\beta}$-Galactosidase in Ripening Tomato Fruits (성열중(成熱中) Tomato 과실(果實)의 ${\beta}$-Galactosidase의 활성변화(活性變化)와 그 특성(特性))

  • Kweon, Sang Oh;Moon, Kwang Deok;Sohn, Tae Hwa
    • Current Research on Agriculture and Life Sciences
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    • v.7
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    • pp.153-163
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    • 1989
  • The activity changes and biochemical properties of ${\beta}$-gal in tomato fruits during ripening were investigated. The total activity was increased during ripening and three isoenzymes (${\beta}$-gal I, II and III) were purified through DEAE Sephadex A-50 and Sephadex G-100 column chromatography. The activities of ${\beta}$gal isoenzymes (${\beta}$-gal I, II and III) during ripening were 69.8, 31.8 and 170.0 units in mature green phase, while those were 48.7, 88.4 and 136.8 units in Red phase, respectively. As the ripening proceeded the activities of ${\beta}$-gal I and III were some what decreased but the activity of ${\beta}$-gal II was incresed more than 2.8 fold. The optimum pH of ${\beta}$-gal I, II and III were 3.9, 4.2 and 3.9 and the optimum temperature of those were $60^{\circ}C$, $56^{\circ}C$ and $60^{\circ}C$, respectively. All isoenzymes were stable at pH 3.6~6.0 and lost their activity about 50% when it heated at $55^{\circ}C$ for 5 minute. $Mg^{{+}{+}}$-activated the three isoenzymes but $Ca^{{+}{+}}$ and SDS inhibited about 30~40%. $Hg^{{+}{+}}$ inhibited completely. The km value of ${\beta}$-gal I, II and III was 0.36mM, 0.63mM and 0.45mM, reaction rate was rapidly increased until the concentration of substrate was $6.0{\times}10^{-5}M$.

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Role of Kupffer Cells in the Vasoregulatory Gene Expression during Hepatic Ischemia/Reperfusion

  • Kim, Yong-Hyuk;Lee, Sun-Mee
    • Archives of Pharmacal Research
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    • v.27 no.1
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    • pp.111-117
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    • 2004
  • Hepatic microcirculatory failure is a major component of reperfusion injury in the liver. Recent data provided some evidence that endothelium-derived vasoconstrictors and vasodilators may be functionally important to the control of the total hepatic blood flow under these conditions of circulatory failure. Since Kupffer cells provide signals that regulate the hepatic response in ischemia/reperfusion (I/R), the aim of this study was to investigate the role of Kupffer cells in the I/R-induced imbalance of vasoregulatory gene expression. Rats were subjected to 60 min hepatic ischemia, followed by 5 h of reperfusion. The Kupffer cells were inactivated by gadolinium chloride ($GdCl_3$, 7.5 mg/kg body weight, intravenously) 1 day prior to ischemia. Liver samples were obtained 5 hrs after reperfusion for RT-PCR analysis of the mRNA for genes of interest: endothelin-1 (ET-1), its receptors $ET_A and ET_B$, endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS) and heme oxygenase-1 (HO-1). ET-1 mRNA expression was increased by I/R. mRNA levels for $ET_A$ receptors showed no change, whereas $ET_B$ receptor transcripts increased in the I/R group. The increases in ET-1 and $ET_B$ mRNA were not prevented by the $GdCI_3$ pretreatment. The mRNA levels for iNOS and eNOS significantly increased within the I/R group with no significant difference between the I/R group and the $GdCl_3$-treated I/R group. HO-1 mRNA expression significantly increased in the I/R group and this increase was attenuated by $GdCI_3$. In conclusion, we have demonstrated that an imbalance in hepatic vasoregulatory gene expression occurs during I/R. Our findings suggest that the activation of Kupffer cells is not required for I/R-induced hepatic microvascular dysfunction.

Effect of Trolox on Altered Vasoregulatory Gene Expression in Hepatic Ischemia/Reperfusion

  • Eum, Hyun-Ae;Lee, Sun-Mee
    • Archives of Pharmacal Research
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    • v.27 no.2
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    • pp.225-231
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    • 2004
  • This study was designed to investigate the effect of Trolox, a hydrophilic analogue of vitamin E, on the alteration of vasoregulatory gene expression during hepatic ischemia and reperfusion (I/R). Rats were subjected to 60 min of hepatic ischemia in vivo. The rats were treated intravenously with Trolox (2.5 mg/kg) or the vehicle as a control 5 min before reperfusion. Liver samples were obtained 5 h after reperfusion for a RT-PCR analysis on the mRNA for the genes of interest. These mRNA peptides are endothelin-1 (ET -1), potent vasoconstrictor peptide, its receptor $ET_A$ and $ET_B$, vasodilator endothelial nitric oxide synthase (eNOS), inducible nitric oxide synthase (iNOS), heme oxygenase-1 (HO-1), tumor necrosis factor-$\alpha$ (TNF-$\alpha$) and cyclooxygenase-2 (COX-2). It was seen that serum alanine aminotransferase and lipid peroxi-dation levels were markedly increased after I/R and Trolox significantly suppressed this increase. In contrast, the glutathione concentration decreased in the I/R group, and this decrease was inhibited by Trolox. ET-1 mRNA expression was increased by I/R, an increase which was prevented by Trolox. The mRNA levels for $ET_A$ receptor was significantly decreased, whereas ET$_{B}$ receptor transcript increased in the I/R group. The increase in $ET_A$ was prevented by Trolox. The mRNA levels for iNOS and HO-1 significantly increased in the I/R group and Trolox attenuated this increase. There were no significant differences in eNOS mRNA expression among any of the experimental groups. The mRNA levels for COX-2 and TNF-$\alpha$ significantly increased in I/R group and Trolox also attenuated this increase. Our findings suggest that I/R induces an imbalanced hepatic vasoregulatory gene expression and Trolox ameliorates this change through its free radical scavenging activity.y.

Degradation of the Pd catalytic layer electrolyte in dye sensitized solar cells (염료감응태양전지에서 Pd 촉매층의 전해질과의 반응에 따른 특성 저하)

  • Noh, Yunyoung;Song, Ohsung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.4
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    • pp.2037-2042
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    • 2013
  • A TCO-less palladium (Pd) catalytic layer on the glass substrate was assessed as the counter electrode (CE) in a dye sensitized solar cell (DSSC) to confirm the stability of Pd with the $I^-/I_3{^-}$electrolyte on the DSSC performance. A 90nm-thick Pd film was deposited by a thermal evaporator. Finally, DSSC devices of $0.45cm^2$ with glass/FTO/blocking layer/$TiO_2$/dye/electrolyte(10 mM LiI + 1 mM $I_2$ + 0.1 M $LiClO_4$ in acetonitrile solution)/Pd/glass structure was prepared. We investigated the microstructure and photovoltaic property at 1 and 12 hours after the sample preparation. The optical microscopy, field emission scanning electron microscopy (FESEM), cyclic voltammetry measurement (C-V), and current voltage (I-V) were employed to measure the microstructure and photovoltaic property evolution. Microstructure analysis showed that the corrosion by reaction between the Pd layer and the electrolyte occurred as time went by, which led the decrease of the catalytic activity and the efficiency. I-V result revealed that the energy conversion efficiency after 1 and 12 hours was 0.34% and 0.15%, respectively. Our results implied that we might employ the other non-$I^-/I_3{^-}$electrolyte or the other catalytic metal layers to guarantee the long term stability of the DSSC devices.

Characterization of Endoglucanase (F-I-III) Purified from Trichoderma sp. C-4 (새로운 섬유소분해 균주 Trichoderma sp. C-4에서 분리한 Endoglucanase (F-I-III)에 대한 연구)

  • Sul Ok Ju;Chung Dae Kyun;Han In Seob;Jeong Choon Soo
    • Korean Journal of Microbiology
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    • v.41 no.1
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    • pp.81-86
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    • 2005
  • One of the endoglucanases, F-I-III, was purified from the culture filtrate of T. sp. C-4 through procedures including chromatography on Sephacryl S-200, DEAE-Sepharose A-50, and Chromatofocusing on Mono-P (FPLC). The molecular weight of the enzyme was determined to be about 56,000 Da by SDS-PAGE, and pI of 4.9 by analytical isoelectric focusing. F-I-III showed the highest enzyme activity at $55^{\circ}C$, and the pH optimum of the enzyme was 5.0. There was no loss of activity when the enzyme was incubated at $50^{\circ}C$ for 24 hours. The specific activity of the enzyme F-I-III toward the CMC was 315.4 U/mg. The Km value for $PNPG_2$ of F-I-III was 2.69 mM. N-terminal sequence of F-I-III was analyzed to be QPGTSTPEVHPKKLTTYK. It showed $95\%$ of homology to that of EGI from T. reesei. The presence of some metal ions (1 mM) had only a little effect on CMCase activity. The treatment of the reducing agents resulted in the increase of endoglucanase activity.

Improvement of Cultural Practices for a New Aromatic Tobacco ST 375-4 I. Effect of the Mulching Method on Yield and Quality (향끽미종 잎담배 ST375-4의 신재배법 연구 제1보 피복방법이 수량 및 품종에 미치는 영향)

  • 정기택;반유선;이정덕
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.26 no.3
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    • pp.273-277
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    • 1981
  • This study was carried out in 1979 to establish the proper mulching culture method for an aromatic tobacco, ST 375-4. Three different methods of mulching were employed: Improved mulching (I. M.), General mulching (G. M.) and Non-mulching (N. M.). The number of seedlings per hole was 5 for I. M., and one for G. M. and N. M. In comparison with N. M., I. M. had shortened final date of leaf harvest by 14 days, enabling curing leaves before the rainy season. It also reduced transplanting labour hours by 44.9%. Yield and price value increased with improved mulching culture. There was little difference in relative light intensity at leaves between N. M. and I. M.

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