• 제목/요약/키워드: maximal condition

검색결과 312건 처리시간 0.028초

Streptomyces luteogriseus KT-10에 의한 Cathepsin B 저해물질의 발효생산 (Production of Cathepsin B Inhibitor by Steptomyces luteogriseus KT-10)

  • 한길환;김상달
    • 한국미생물·생명공학회지
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    • 제27권6호
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    • pp.458-465
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    • 1999
  • Streptomyces luteogriseus KT-10 isolated from Korean farm soil produced a strong cathepsin B inhibitor. Optimal conditions for the cathepsin B inhibitor production by s. luteogriseus KT-10 were evaluated. The cathepsin B inhibitor was produced with maximal yield in the cultural condition of pH 7.0 and $25^{\circ}C$ for 4 days. Optimal medium for the cathepsin B inhibitor production was determined to be a medium containing 20g, peptone 3g, yeast extract 1g, K2HPO4 0.5g, MgSO4.7H2O 0.5g, NaNO3 0.5g, NaCl 0.5g per l. The cathepsin B inhibitor produced by S. luteogriseus KT-10 could also inhibit the other proteinases such as trypsin, papain, and cathepsin D.

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MATHEMATICAL ANALYSIS OF NONLINEAR DIFFERENTIAL EQUATION ARISING IN MEMS

  • Zhang, Ruifeng;Li, Na
    • 대한수학회보
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    • 제49권4호
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    • pp.705-714
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    • 2012
  • In this paper, we study nonlinear equation arising in MEMS modeling electrostatic actuation. We will prove the local and global existence of solutions of the generalized parabolic MEMS equation. We present that there exists a constant ${\lambda}^*$ such that the associated stationary problem has a solution for any ${\lambda}$ < ${\lambda}^*$ and no solution for any ${\lambda}$ > ${\lambda}^*$. We show that when ${\lambda}$ < ${\lambda}^*$ the global solution converges to its unique maximal steady-state as $t{\rightarrow}{\infty}$. We also obtain the condition for the existence of a touchdown time $T{\leq}{\infty}$ for the dynamical solution. Furthermore, there exists $p_0$ > 1, as a function of $p$, the pull-in voltage ${\lambda}^*(p)$ is strictly decreasing with respect to 1 < $p$ < $p_0$, and increasing with respect to $p$ > $p_0$.

POSITIVENESS FOR THE RIEMANNIAN GEODESIC BLOCK MATRIX

  • Hwang, Jinmi;Kim, Sejong
    • 대한수학회논문집
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    • 제35권3호
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    • pp.917-925
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    • 2020
  • It has been shown that the geometric mean A#B of positive definite Hermitian matrices A and B is the maximal element X of Hermitian matrices such that $$\(\array{A&X\\X&B}\)$$ is positive semi-definite. As an extension of this result for the 2 × 2 block matrix, we consider in this article the block matrix [[A#wijB]] whose (i, j) block is given by the Riemannian geodesics of positive definite Hermitian matrices A and B, where wij ∈ ℝ for all 1 ≤ i, j ≤ m. Under certain assumption of the Loewner order for A and B, we establish the equivalent condition for the parameter matrix ω = [wij] such that the block matrix [[A#wijB]] is positive semi-definite.

호알칼리성, 고온성 Bacillus sp. TA-11 에 의한 $\beta$-Fructofuranosidase의 생산 (Producton of $\beta$-Fructofuranosidase from Alkalophilic, Thermophilic Bacillus sp. TA-11)

  • 최영준;이종수
    • 한국미생물·생명공학회지
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    • 제23권2호
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    • pp.197-202
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    • 1995
  • The conditions for the $\beta$-fructofuranosidase production from alkalophilic, thermophilic Bacillus sp. TA-11 were investigated. The maximal enzyme production was obtained when the strain was cultured at 50$\circ$C for 36 hrs with batch culture in the optimal medium containing 1.0% sucrose, 0.6% yeast extract, 0.1% each of KH$_{2}$PO$_{4}$, K$_{2}$HP0$_{4}$, NaH$_{2}$PO$_{4}$, and initial pH 9.5, and the final enzyme activity under the above condition was 102 units per ml of cell free extract.

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선로과부하해소를 고려한 최적부하간단에 관한 연구 (A Study on the Optimal Load Shedding Considering Alleviation of the Line Overload)

  • 송길영;이희영
    • 대한전기학회논문지
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    • 제36권6호
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    • pp.381-389
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    • 1987
  • This paper presents a method for optimal load shedding in preserving a system security following abnormal condition as well as a sudden major supply outage. The method takes account of static characteristic of generators control and voltage and system frequency characteristic of loads. The optimization problem is solved by a gradient technique to get the maximal effect by the least quantity of load shedding considering line overloads as well as voltage disturbances and system frequency. The method is illustrated on a 8-bus system. It has been found that the use of the proposed algorithm for model systems alleviate the line overload more efficiently than the former method. It is believed that this method will be useful in security studies and operational planning.

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Production of Antihypertensive Angiotensin I-Converting Enzyme Inhibitor from Malassezia pachydermatis G-14

  • Jeong, Seung-Chan;Kim, Jae-Ho;Kim, Na-Mi;Lee, Jong-Soo
    • Mycobiology
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    • 제33권3호
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    • pp.142-146
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    • 2005
  • To produce a novel antihypertensive angiotensin I-converting enzyme (ACE) inhibitor from yeast, a yeast isolate, designated G-14 showing the highest ACE inhibitory activity was obtained and identified as Malassezia pachydermatis based on morphological, biochemical and cultural characteristics. The maximal extracellular ACE inhibitor production was obtained from M. pachydermatis G-14 when the strain was cultured in YEPD medium containing 0.5% yeast extract, 3.0% peptone and 2.0% glucose at $30^{\circ}C$ for 24 h and the final ACE inhibitory activity was 48.9% under the above condition.

신생 돼지심장에서 상온의 Krebs 용액 관류에 따른 좌심실 기능의 변화 (Left Ventricular Function Changes Under Normothermic Krebs Perfusate in Newborn Piglet)

  • 오봉석;나국주;이동준
    • Journal of Chest Surgery
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    • 제23권6호
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    • pp.1067-1073
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    • 1990
  • To clarify the changes of left ventricular function under normothermia, the time interval between the onset of ischemia and the beginning of contracture of left ventricle[TIC] were recorded in newborn piglet. Myocardial performance was assessed using intraventricular balloon to determine compliance and systolic function after 5 to 10 minutes interval per-fusing normothermic substrate free Krebs solution as a perfusate. The time to onset TIC was 29.5\ulcorner1.7 minutes and peak ischemic contracture was 46.7\ulcorner4.0 minutes[p<0.01]. In myocardial performance, systolic function of left ventricle[defined as cardiac contractility] was kept until 25 minutes of perfusion, but was decreased abruptly after 30 minutes of perfusion[p<0.0018] and diastolic function of left ventricle[defined as diastolic compliance] was kept until 15 minutes of perfusion, but was decreased after 20 minutes of perfusion [p=0.00\ulcorner9]. This study demonstrated maximal time of the tolerance to normothermic global ischemia and functional changes of left ventricle using Krebs perfusate under the same condition.

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액정표시소자에서 화면의 명암대비와 밝기를 극대화하는 기본조건: II. 다색광의 경우 (Fundamental condition for the realization of maximal contrast and brightness in liquid crystal display device: II. Polychromatic case)

  • 양병관;김진승;노봉규
    • 한국광학회지
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    • 제14권5호
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    • pp.498-503
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    • 2003
  • 뽀앙카레 공에서 액정셀의 전기광학적 편광투과특성을 분석하고, 이를 바탕으로 여러 파장에 대해 액정표시소자의 밝기와 명암대비를 최적화하는 위상판의 규격을 정하는 기본조건을 찾았다. 이 조건에 따르면 두 파장에 대해서는 분산특성이 적절하게 조절된 위상판 2매, 세 파장의 경우에는 두 파장으로 근사하거나 위상판 3매가 필요하다.

INTRINSIC BRIGHTNESS TEMPERATURE OF COMPACT RADIO SOURCES AT 86GHZ

  • Lee, Sang-Sung
    • 천문학회지
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    • 제46권6호
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    • pp.243-251
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    • 2013
  • We present results on the intrinsic brightness temperature of a sample of compact radio sources observed at 86 GHz using the Global Millimeter VLBI Array. We use the observed brightness temperatures at 86 GHz and the observed superluminal motions at 15 GHz for the sample in order to constrain the characteristic intrinsic brightness temperature of the sample. With a statistical method for studying the intrinsic brightness temperatures of innermost jet cores of compact radio sources, assuming that all sources have the same intrinsic brightness temperature and the viewing angles of their jets are around the critical value for the maximal apparent speed, we find that sources in the sample have a characteristic intrinsic brightness temperature, $T_0=4.8^{+2.6}_{-1.5}{\times}10^9K$, which is lower than the equipartition temperature for the condition that the particle energy equals to the magnetic field energy. Our results suggest that the VLBI cores seen at 86 GHz may be representing a jet region where the magnetic field energy dominates the total energy in the jet.

Effect of agitation speed on production of exopolymer by Pseudomonas elodea NK-2000

  • 이남규;김현숙;손창우;이유정;조영수;이진우
    • 한국생물공학회:학술대회논문집
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    • 한국생물공학회 2000년도 추계학술발표대회 및 bio-venture fair
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    • pp.334-337
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    • 2000
  • Extracellular polysaccharide was produced by Pseudomonas elodea NK-2000 under nitrogen limitation and aerobic condition, The effect of agiatation speed on cell growth and production of exopolymer was investigated. The agitation speed of 7.5 L fermentor ranged from 200 to 500 rpm. Production of exopolymer increased with higher agitation speed. Maximal cell growth and production of exopolymer from 2% glucose were 3.35 g/l and 3.80 g/l, respectively when agitation speed was 400 rpm.

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