• Natural Product Sciences
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• v.16 no.4
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• pp.203-206
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• 2010

A pyridyl alkaloid, 3-pyridylcarbinol (1) and benzoic acid derivatives, 4-hydroxy benzoic acid (2), 4-hydroxyactophenone (3), vanilic acid (4), and benzoic acid (5) were isolated from the rhizomes of Anemarrhena asphodeloides on the basis of spectroscopic and physicochemical analyses including 1D- and 2D- NMR techniques as well as by comparison of their data with the published values. Compounds 1 - 5 were isolated for the first time from this plant source.

• 한국약용작물학회:학술대회논문집
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• 2008.11a
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• pp.243-244
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• 2008

• JSTS:Journal of Semiconductor Technology and Science
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• v.8 no.2
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• pp.170-177
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• 2008

In the present work a methodology to minimize short channel effects (SCEs) by modulating the effective channel length is proposed to design 25 nm single and double gate-source/drain underlap MOSFETs. The analysis is based on the evaluation of the ratio of effective channel length to natural/ characteristic length. Our results show that for this ratio to be greater than 2, steeper source/drain doping gradients along with wider source/drain roll-off widths will be required for both devices. In order to enhance short channel immunity, the ratio of source/drain roll-off width to lateral straggle should be greater than 2 for a wide range of source/drain doping gradients.

• Journal of Korea Multimedia Society
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• v.19 no.11
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• pp.1891-1899
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• 2016

Recently food problem and crop disaster have been increased continuously because of the meteorological changes. These cause rising cost for crops continuously and irregularly. Some researchers have studied straight structure of device for hydroponics and plant factory previously to solve a fundamental part of these problems. However, there are several problems such as limited crop cultivation space, providing irregular nutrients for crops, and lack of monitoring interfaces. For them, we propose an optimal growth and development crops management system using light source tracking and recirculation of nutrient solution method to supply nutrient continuously based on IoT. In order to evaluate the performance of our system, we compared and analyzed in terms of two viewpoints, the tracking analysis for natural light source measurement and the growth of crops through artificial light, LED, respectively. We confirmed that the higher the duty ratio of LED, the larger the crop's size, particularly. As well as, for about 1 month, we compared with the existing natural light growing environment and that of our system. It was confirmed that the size of the crops grown through our system is about three times larger than that of natural light natural crops.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.7
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• pp.976-982
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• 2002

In this study, smoke movement in tunnel fire with natural ventilation shaft has been investigated with various size of fire source. Gasoline pool fire with different size of diameter - 73mm, 100mm, 125mm and 154mm - was used to describe fire source. Experimental data is obtained with 1/20 model tunnel test and its results are compared with numerical results. The computation were carried out using FDS 1.0 which is a field model of fire-driven now. Temperature profiles between measured and predicted data are compared along ceiling and near the ventilation shaft. Both results are in good agreement with each other. In order to evaluating a safe egress time in tunnel fire, horizontal smoke front velocity was measured in model tunnel fire tests and those are compared with numerical results. According to the presence or absence of natural ventilation shaft, ventilation effect are estimated quantitatively. Finally, this paper shows that computational fluid dynamics(CFD) is applicable to predict fire-induced flow in tunnel.

• 한국생물공학회:학술대회논문집
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• 2002.04a
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• pp.173-176
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• 2002

Effect of carbon source and culture conditions involved in the concentration of dissolved oxygen on cell growth and the production of pullulan by A. pullulans HP2001 were investigated. Among those carbon sources, glucose was found to be the best carbon source for the production of pullulan by A. pullulans HP2001. Maximal production of pullulan by A. pullulans HP2001 was 26.6 g/ f when concentrations of glucose and yeast extract were 8% (w/v) and 0.25% (w/v), respectively. It was found that aeration rate, agitation speed and inner pressure of a bioreactor, which were some of physiological factors involved in the dissolved oxygen in the medium may affect cell growth and the production of pullulan by A. pullulans HP2001.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.15 no.5 s.98
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• pp.604-611
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• 2005

The relationship between floor impact sound and vibration has been studied by field measurements, and the vibration modal characteristics have been analyzed. Vibration levels impacted by a standard heavy-weight impact source have been predicted according to the main design parameters using finite element method. Experimental results show that the dominant frequencies of the heavy impact sounds range below 100 Hz and that they are coincident with natural frequencies of the concrete slab. In addition, simple 2-dimensional finite element models are proposed to substitute 2 types of 3-dimensional models of complicated floor structural slabs those by The analytical result shows that the natural frequencies from first to fifth mode well correspond to those by experiments with an error of less than $12\%$, and acceleration peak value iscoincident with an error of less than $2\%$. Using the finite element model. vibration levels areestimated according to the design Parameters, slab thickness, compressive strength, and as a result, the thickness is revealed as effective to increase natural frequencies by $20\~30\%$ and to reduce the vibration level by 3$\~$4 dB per 30 mm of extra thickness.

• YAKHAK HOEJI
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• v.37 no.4
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• pp.389-396
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• 1993

An Actinomycetes strain JB isolated from Mt. Hanla had a strong antimicrobial activity against gram positive bacteria and tumor cell growth inhibition. Especially, it couldn't degrade starch and casein as organic compounds. It was resist on lincomycin and rifampicin. The spore mass of strain JB which was arethrospore was white. DAP of the cell wall was L, L-DAP. Antimicrobial material was heat stable, dissolved in ethyl acetate, and not dissolved in butanol. In the pressnce of 0.1% phenol and 4% sodium chloride, strain JB could grow, but it didn't growth at below $10^{\circ}C$. Strain JB didn't use dextran, sodium acetate and sodium citrate as sole carbon source and L-cystein and L-thereonine as nitrogen source. The filtered broth of strain JB had the antimicrobial activity against gram positive bacteria, especially Staphylococcus aureus (ATCC 65389) and the growth inhibition of tumor cell line.

• Proceedings of the PSK Conference
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• 2003.10b
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• pp.198.1-198.1
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• 2003

As part of our systematic study for Korean Compositae plants, we have studied Saussurea nutans, collected at Gangwon Province on August 2001. Phytochemical studies on various species of genus Saussurea have resulted in the isolation sesquiterpene, triterpene and flavonoid$\^$1)/. S. nutans has been used for the treatment of rheumatic arthritis and dysmenorrhea in the Chinese folk medicine$\^$2)/. However, chemical constituents of this plant have not been reported until now. The MeOH extract of the aerial parts of this source was solvent fractionated into n-hexane, methylene chloride, ethyl acetate and BuOH soluble portions. (omitted)

• Korean Journal of Pharmacognosy
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• v.11 no.3_4 s.43
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• pp.219-227
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• 1980