• 대한한의학방제학회지
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• 제21권1호
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• pp.36-50
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• 2013

Objectives : To clarify the possible effect of Lycium chinese Mill (LC)., Morus alba L (MA)., and Lycium chinese Mill. +Morus alba L. (LC+MA), we have examined their influence on the development of pulmonary eosinophilic inflammation in the asthmatic murine model. Methods : Female Balb/c mice (5weeks) were immunized on two different days (21 days and 7 days before inhalational exposure) by intraperitonial injections of 0.2ml alum-precipitated Ag containing $100{\mu}g$ of OVA bound to 4 mg of aluminum hydroxide in PBS. Seven days after the second sensitization, mice were exposed to aerosolized ovalbumin for 30 minutes/day on 3 days/week for 8 weeks (at a flow rate of 250 L/min, 2.5% ovalbumin in normal saline) and, LC, MA, and LC+MA (500 mg/kg) were orally administered 3 times per a week for 8 weeks. Results : The suppressive effect of LC, MA, and LC+MA were demonstrated by the accumulation of eosinophills into airways, with the reduction of eosinophil, total lung leukocytes numbers. These were correlated with the marked reduction of IL-5, IL-13 and IL-4 levels in the BALF and serum. OVA-specific IgE levels were also decreased in serum and BAL from these mice. LC, MA, and LC+MA decreased eosinophil CCR3 expression and CD11b expression in lung cells. Conclusions : These results indicate that LC, MA, and LC+MA have high inhibitory effects on airway inflammation and hyper-responsiveness in the asthmatic murine model. The suppression of IL-5, IgE, eosinophil CCR3 expression and CD11b expression, and the increase of IFN-${\gamma}$ production in BALF seem to contribute to this effect. Hence, the results indicated that LC, MA, and LC+MA could act as a immuno-modulator which possesses anti-inflammatory and anti-asthmatic property by modulating the imbalance between Th1 and Th2 cytokines.

• 전력전자학회논문지
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• 제20권3호
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• pp.239-246
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• 2015

A novel control method of a three-phase PWM inverter with LC filter is proposed. The transfer function of LC filter is the same as that of second-order low pass filter(LPF), which has a zero damping ratio. A simple method of implementing second-order LPF with damping ratio is to add a resistor in an LC circuit. However, in a real power system, adopting damping resistors is impractical because it results in losses proportional to the square of the current flowing through the resistors. Instead of inserting resistors, the proposed control strategy utilizes the measured capacitor voltages to control the oscillation of LC circuit. The overall transfer function of the proposed method is the same as a second-order LPF, and its damping ratio is controllable via control variables. The current controller can have overshoots caused by LC filter. Improved current controller is implemented by an equivalent second-order of LC filter. A 7.5 kVA PWM converter and a PWM inverter with a 5.5 kW induction motor are set up to verify the proposed control algorithm. Test waveforms are also presented to verify the proposed LC filter control algorithm.

• Computers and Concrete
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• 제32권6호
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• pp.577-594
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• 2023

Engineered cementitious composites with calcined clay limestone cement (LC³-ECC) as a kind of green, low-carbon and high toughness concrete, has recently received significant investigation. However, the complicated relationship between potential influential factors and LC³-ECC compressive strength makes the prediction of LC³-ECC compressive strength difficult. Regarding this, the machine learning-based prediction models for the compressive strength of LC³-ECC concrete is firstly proposed and developed. Models combine three novel meta-heuristic algorithms (golden jackal optimization algorithm, butterfly optimization algorithm and whale optimization algorithm) with support vector regression (SVR) to improve the accuracy of prediction. A new dataset about LC³-ECC compressive strength was integrated based on 156 data from previous studies and used to develop the SVR-based models. Thirteen potential factors affecting the compressive strength of LC³-ECC were comprehensively considered in the model. The results show all hybrid SVR prediction models can reach the Coefficient of determination (R²) above 0.95 for the testing set and 0.97 for the training set. Radar and Taylor plots also show better overall prediction performance of the hybrid SVR models than several traditional machine learning techniques, which confirms the superiority of the three proposed methods. The successful development of this predictive model can provide scientific guidance for LC³-ECC materials and further apply to such low-carbon, sustainable cement-based materials.

• 분석과학
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• 제9권1호
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• pp.1-12
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• 1996

열에 불안정하면서 -OH기를 함유하는 미지의 화합물은 LC/TSP/MS에서 [${MNH_4}^+$] 이온, [$MH^+$] 이온, 그리고 [$MH^+-OH$] 이온의 생성이 가능하며, 이들 이온의 m/z값의 차이가 17로서 같기 때문에 이들의 생성 정도에 따라 분자량 추정에 혼란이 일어날 수가 있었다. 따라서 다른 보완 가능한 실험결과가 요구되며 $CF_3COOD+NH_4OH$ 이온화 용액을 사용하여 그 유용성을 검토하였다. 또한 LC/TSP/MS에서 생성되는 토막이온들이 필라멘트의 전자살에 의해 생성되는 것인지 아니면 다른 어떤 생성기전이 존재하는지를 검토하였다.

• KSBB Journal
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• 제9권2호
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• pp.115-121
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• 1994

240ml의 시료를 정제할 수 있는 30channel의 preparative-scale 자유유동전기이동 분리장치를 제작한 후 렌즈콩으로부터 lentil lectin(LcH)을 전기 집속법으로 분리하였다. 분리된 각 분획을 PAGIEF젤에서 silver staining했을 때 불순물이 전혀 검출되지 않을 정도의 고순도 lectin을 얻을 수 있었다. 이 때 ampholyte로서 HEPES(50mM) -Tris(50mM) -urea(3M) 등을 사용하였으며 50mM Histidine(pI 7.65)인 경우 가장 분리도가 가장 좋았다. LcH는 보통의 조건하에서 LcH-A와 LcH-B의 두가지 순수한 형태로만 나타났으며 따라서 이 장치를 사용하여 다단 분리 정제를 할경우 두 성분의 완전한 분리도 가능함을 보여 주었다.

• 분석과학
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• 제20권3호
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• pp.198-203
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• 2007

수용액상에 존재하는 3-monochloropropane-1,2-diol (3-MCPD)의 LC-MS를 이용한 분석방법을 개발하였다. 수용액 시료에 수산화나트륨 용액을 첨가하여 강알칼리 상태를 유지시킨 후, 3-MCPD의 유도체화를 위하여 benzoyl chloride $25{\mu}L$을 넣어 직접 반응시켰다. 반응 후 유도체를 pentane으로 추출하여 LC-MS의 selected ion monitoring (SIM) 법으로 정량하였다. 분석결과 검량선은 $1.0-100{\mu}g/mL$ 농도범위에서 $r^2=0.992$의 상관관계 계수를 갖는 좋은 직선성을 나타내었으며, 검출한계는 $0.01{\mu}g/mL$ 이하였다. LC-MS에 의한 분석방법의 회수율은 92.3-98.0%이었다.

• BMB Reports
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• 제31권2호
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• pp.117-122
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• 1998

Changes of lipocortin 1 (LC1) in the brain induced by immobilization stress were investigated in rats. Rats were immobilized for 0,1,2,3,4, and 5 h, and the brain slices were immunostained with anti-human LC1 antibodl (anti-LC1). Immunoreactivity of LCI (iLC1) was most prominent in neuronal cell bodies and processes of hippocampal CA regions and dentate gyrus. At rest without stress, most of the LC1 in the neuron located in the cytoplasm with the nuclei exhibiting relatively scarce immunoreactivity. Immobilization stress changed this intracellular distribution of LC1 by increasing nuclear LC1. The change was apparent in 1 h and reached the peak by 3 h. However, by 5 h of immobilization, the distribution pattern returned to that of the resting state. This transient nuclear translocation of LC1 was most prominent in $CA_1$ pyramidal neurons, and was not observed in areas other than the hippocampus. Adrenalectomy abolished this transient translocation of LC1. The roles of hippocampal LC1 as a mediator of glucocorticoid feedback signal and/or as an intracellar stress signaling protein could be suggested.

• JSTS:Journal of Semiconductor Technology and Science
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• 제13권3호
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• pp.207-212
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• 2013

A new CMOS voltage-bias differential LC voltage-controlled oscillator (LC-VCO) with active source degeneration is proposed. The proposed degeneration technique preserves the quality factor of the LC-tank which leads to improvement in phase noise of VCO oscillators. The proposed VCO shows the high figure of merit (FOM) with large tuning range, low power, and small chip size compared to those of conventional voltage-bias differential LC-VCO. The proposed VCO implemented in 0.18-${\mu}m$ CMOS shows the phase noise of -118 dBc/Hz at 1 MHz offset oscillating at 5.03 GHz, tuning range of 12%, occupies 0.15 $mm^2$ of chip area while dissipating 1.44 mW from 0.8 V supply.

• 대한수의학회지
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• 제40권3호
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• pp.451-461
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• 2000

The locus coeruleus(LG) is known to be observed a sexual dimorphism in rat CNS. LC is the largest collections of norepinephrine(NE)-containing neurons in the mammalian brain. Especially in rat, all LC neurons contained NE unlike other mammalians, so that specific reactions were found in the tyrosine-hydroxylase(TH) immunoreactive neurons. Sexual dimorphism of rat LC has affected by genes before sex hormone appeared, thereafter affected by sex hormones. In these day, many scientists founded morphological differences between male and female LC morphology, but differences of entire structure was not founded. Thus we investigated sex differences of the LC neuron's morphology in rat by three-dimensional(3-D) reconstruction using Confocal laser scanning microscopy(CLSM). We reported that neuron's shape was relatively-large multipolar neurons and neuron's processes in dorsal LC proceeded to ventral direction in the male and female rat. Male had a longer anterior-posterior length than female had in dorsal LC. In addition to middle-LC, male rat's LC had a more thicker posterior region but had not viewed in a previous study. In reverse, female rat's LC had a thicker anterior region like a previous study. This results using 3-D reconstruction by CLSM showed that the male's LC was more wide-ranging than female's relatively.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1996년도 하계학술대회 논문집 A
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• pp.588-590
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• 1996

An AC induction motor or constant speed characteristics has been widely used as power source because of simple structure and low maintenance cost in industrial field. The variable frequency AC source with a conventional inverter which is composed or power semi-conductors and drive systems contains much noises in sine wave current due to high speed switching or direct current. In this paper, the low pass LC filter for a variable speed induction motor driven by a full bridge inverter is introduced to solve EMI problem originated by much noise current. The modified LC filter based on the 3rd order Butterworth LC filter is used for the computer simulations and real experiments. The characteristics or proposed LC filter are investigated through FET analysis.