• Microbiology and Biotechnology Letters
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• v.27 no.6
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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.

• Bulletin of the Korean Mathematical Society
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• v.49 no.4
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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 $p$ > $p_0$.

• Communications of the Korean Mathematical Society
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• v.35 no.3
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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#w_ijB]] whose (i, j) block is given by the Riemannian geodesics of positive definite Hermitian matrices A and B, where w_ij ∈ 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 = [w_ij] such that the block matrix [[A#w_ijB]] is positive semi-definite.

• Microbiology and Biotechnology Letters
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• v.23 no.2
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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.

• The Transactions of the Korean Institute of Electrical Engineers
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• v.36 no.6
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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.

• Mycobiology
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• v.33 no.3
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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.

• Journal of Chest Surgery
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• v.23 no.6
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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.

• Korean Journal of Optics and Photonics
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• v.14 no.5
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• pp.498-503
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• 2003

We analyze the electro-optic polarization transmission characteristics of liquid crystal cells in the Poincare sphere representation. We determine fundamental conditions on maximizing of brightness and contrast ratio of liquid crystal display devices for polychromatic light by use of retardation films. For optimizing two colors, at least two properly designed retardation films are needed, and for three wavelengths, either it can be approximated to the two-color case or three retardation films are needed.

• Journal of The Korean Astronomical Society
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• v.46 no.6
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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.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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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.