• Proceedings of the Optical Society of Korea Conference
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• 1991.06a
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• pp.110-114
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• 1991

A guided-wave electrooptic Mach-Zehnder interferometric modulator was fabricated on Y-cut acoustic grade LiNbO3 process. In order to reduce the electrode capacitance, serial capacitance electrode(SCE) structure was adopted. Extinction ratio more than 30dB was obtained with V$\pi$ of 4.69 volt at λ= 0.6328${\mu}{\textrm}{m}$. Frequency response was measured by using the swept frequency technique, and the bandwidth of the modulator was about 1GHz.

• 제어로봇시스템학회:학술대회논문집
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• 2000.10a
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• pp.319-319
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• 2000

In this paper, A dead-time compensator (DTC) for the processes with long dead-time is proposed. The processes which consist of dead-time, time-constant, gain are estimated by the linear least squares method in the frequency domain. A Smith predictor(SP) modified by including a filter becomes a two degree of freedom DTC. So the proposed DTC can yield the desirable setpoint and load disturbance responses separately. PI controller is used for the primary controller and the filter is tuned to be robust. Simulation examples demonstrate the properties of the proposed DTC.

• 한국초전도학회:학술대회논문집
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• v.12
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• pp.16-16
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• 2002

• The Transactions of the Korean Institute of Electrical Engineers
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• v.37 no.3
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• pp.146-154
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• 1988

The computer simulation of speed and phase control system has been carried out in this study. The load of permanent magnet type synchronous motor is not constant in this system. The cost function method has been used in obtaining the optimal gain of PI controller and the rotor position angle of phase controller has been compensated depending on the load and speed variation. This analysis also shows that the current of d-axis component is zero under the variable a load conditions and the torque per unit current can be maximized.

• Proceedings of the KIEE Conference
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• 2001.11b
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• pp.320-322
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• 2001

본 논문에서는 전압 sag보상을 하기 위한 DSTATCOM 제어기를 설계하고 EMTDC/PSCAD로 확인하였다. DSTATCOM의 전류성분을 d,q분해 해석을 통하여 상태방정식을 유도하고 부하모델과 네트워크의 제약조건을 결합 모델을 제시하였다. 1선 지락 사고시 PI 제어시보다 LQR 제어의 응답 특성이 우수함을 검증하고 전압 sag가 개선됨을 보였다.

• Proceedings of the Korean Society of Toxicology Conference
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• 2003.10b
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• pp.180-180
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• 2003

Peroxisome proliferator-activated receptor gamma (PPAR-gamma), a member of the nuclear hormone receptor superfamily, is involved in the suppression of growth of several types of tumors such as liposarcoma, cancers of breast, prostate, and colon, possibly through induction of cell cycle arrest and/or apoptosis.(omitted)

• Asian-Australasian Journal of Animal Sciences
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• v.22 no.10
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• pp.1429-1436
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• 2009

Adiponectin is an adipocyte-derived protein that has a regulatory role in energy homeostasis and influences insulin sensitivity. Its effects on glucose utilization and lipid metabolism are mediated by AdipoR1 and AdipoR2. How insulin affects adiponectin gene expression and secretion is still controversial. This study was conducted to determine the expression of adiponectin, AdipRs and $PPAR-\gamma$ during the differentiation of bovine preadipocytes and the effect of insulin on expression of these genes in bovine adipocytes. The bovine preadipocytes started to accumulate lipids three days after differentiation was induced, with increased expression of adiponectin, AdipoR2 and $PPAR-\gamma$ mRNAs. Insulin decreased the expression of adiponectin mRNA in a dose- and time-dependent fashion, and the inhibition was detectable at insulin concentrations as low as 10 nM and as early as 2 h after addition of 100 nM insulin. Insulin also inhibited the expression of AdipoR2 mRNA at concentrations from 1 to 1,000 nM or 24 h after addition of 100 nM insulin, but did not affect the expression of AdipoR1 in bovine adipocytes. Inhibition of PI3K with LY294002 reversed the inhibition of adiponectin and AdipoR2 mRNA expression by insulin. These results suggest that insulin suppresses the expression of adiponectin and AdipoR2 at least partially via the PI3K signal pathway.

• Journal of Institute of Control, Robotics and Systems
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• v.22 no.2
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• pp.126-132
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• 2016

The root-locus method is often employed when a controller is designed to find controller gain. It is usually used to determine one parameter gain while most controllers for industrial applications have more than one controller gain. For example PID controller has three controller gains, i.e. P, I, and D gains. Thus the conventional root-locus technique cannot complete the design of a controller with more than one controller gain. One way to overcome this drawback has been to apply the root-locus technique for one parameter while other parameters are assumed to be proportional to the parameter or to be constant. However this approach could lead to limited performance of the controller and if we try to adjust the proportional ratio or constants then it could be a long and tedious process of trial and error. Thus it is required to find an effective method for the root-locus technique to design controllers with more than one parameter. To this end this paper proposes an extended root-locus method for controllers with two parameters. In this paper Matlab is used as a computation tool to show the effectiveness of our method by solving examples numerically. As a result we obtained an extended root-locus illustrated in two-dimensional space for a control system with two parameters. The paper then presents how to find two controller gains based on this result of the extended root-locus. The main idea is that we can find the parameters by approaching the desired poles. It is expected that the proposed idea will help control engineers to easily design control systems using the root-locus technique, resulting in more accurate and faster control systems. Note that the extended root-locus idea can be applied to controller design problems with multiple parameters.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.4
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• pp.771-777
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• 2008

Chungpaesagan-tang which is used for treating patients of brain in cerebrovascular disease frequently from clinical doctor has not reported about the effect of neuronal aptosis caused of brain ischemia. The aim of this study is to investigate effect of Chungpaesagan-tang protecting neuronal cells from being damaged by brain ischemia through using organotypic hippocampal slice cultures. We caused ischemic damage to organotypic hippocampal slice cultures by oxygen and glucose deprivation. And added Chungpaesagan-tang extract to cultures. thereafter we measured area percentage of propidium iodide (PI)-stained neuronal cell, lactate dehydrogenase (LDH) levels in culture media and Terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling (TUNEL)-positive cells. Area percentage of PI-stained neuronal cells and count of TUNEL-positive cells in CA1 and DG area of organotypic hippocampal slice culture were significantly decreased in pertinent density level of Chungpaesagan-tang extract. LDH levels in culture media of organotypic hippocampal slice culture were significantly decreased in pertinent density level of Chungpaesagan-tang extract. Within pertinent density level, Chungpaesagan-tang has cell protection effect that prevents brain ischemia damaging neuronal cells and apoptosis increasing.

• Korean Journal Plant Pathology
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• v.14 no.4
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• pp.339-344
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• 1998

Since the leaf inoculation procedures are time-consuming and require considerable growth chamber space, a rapid dioassay method for screening of pathogenicity of Didymella bryoniae, a casual agent of gummy stem blight in watermelon, was established in this paper. The method produced reliable results within 8 days ( 5 days for growing seedlings and 3 days for rapid disease response in the seedlings). After contaminants in the root of 4~5 day-old seedlings had been washed using sterilized water, 5 seedlings were dipped into a vial containing 12 ml of conidial suspension (106 cells/ml). After the vials were placed in a growth chamber (22$^{\circ}C$, RH 50%, 14hr light/10hr darkness) for 3 days, susceptibility and resistance of cultivars were determined by the degree of disease response on cotyledon. The result of obtained by the dip-inoculation method was well coincided with the results by the leaf inoculation procedures and the result that had been observed for several years in the field. Screening of collected watermelon cultivars by the dip-inoculation method revealed that all the 21 domestic cultivars collected were susceptible and only 3 foreign cultivars (PI 189225, PI 482322 and IT 188207) were resistant among 18 cultivars A cucumber cultivar (Marketer) and bitter cucumber were proven to be resistant against the D. bryoniae among 8 other different cucurbits tested. The SDS-PAGE patterns of total proteins from a susceptible (Keumcheon) and a resistant (PI 189225) watermelon cultivars were compared 0, 12, 24 and 36 hrs after inoculation. The amounts of two distinct protein bands (24 kDa and 70 kDa) were gradually increased after inoculation in both cultivars.