• Proceedings of the KIEE Conference
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• 2004.04a
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• pp.187-191
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• 2004

Photovoltaic and wind power generation have an advantage of unpolluted and unlimited amount of energy resource. Since there is such an advantage in these energies, But photovoltaic system and wind system cannot always generate stable output with ever-changing weather condition. In this paper, the auxiliary power generator for hybrid system(photovoltaic 500[W], wind power generation 400[W]) was suggested. the auxiliary power generator that uses elastic energy of spiral spring to photovoltaic system was also added for present system. when output of photovoltaic system gets lower than 24[V], power was continuously supplied to load through the inverter by charging energy of spiral spring operates in DC generator.

• The Journal of Korean Medicine
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• v.26 no.3 s.63
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• pp.98-109
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• 2005

Objectives : This study was designed to identify the effects of Salvia Miltiorrhiza or antibacterial activity against Streptococcus pneumoniae ATCC 33400. Methods : The ethanol- and water-extracts of more than 80 oriental herbal medicines were investigated by the Kirby-Bauer method to determine their inhibitory effect on growth of S. pneumoniae ATCC 33400 in vitro. Of thorn, Salvia Miltiorrhiza was selected. Results : The ethanol-soluble extract of Salvia Miltiorrhiza showed relatively high antibacterial activity against S. pneumoniae ATCC 33400. However, the water-soluble extract of Salvia Miltionrhiza showed no antibacterial activity. The ethanolic extract was forker fractionated with organic solvents such as hexane, chloroform, and ethyl acetate in that order. Among the fraction tested, the chloroform fraction showed the highest antibacterial activity, when the ethanol-soluble extract of Salvia Miltiorrhiza minimal inhibitory concentration (MIC) was 25${\mu}g/ml$. Conclusions : Further study should be carried out to identity of the cell growth inhibition effects of S. pneumoniae ATCC 33400.

• The Journal of Internal Korean Medicine
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• v.25 no.4
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• pp.433-441
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• 2004

The posterior cerebral arteries supply the temporal and occipital lobes of the left cerebral hemisphere and the right hemisphere. Clinical symptoms associated with occlusion of the posterior cerebral artery are visual abnormalities including opposite visual field defects, hallucination, visual amnesia and a variety of other symptoms, including confusion, cognitive disorders, thalamic syndrome, Weber's syndrome, contralateral hemplegia. This case report is about a patient with visual and cognitive abnormalities caused by posterior cerebral artery infarction. He was regarded as Soyangin(少陽人) in constitution and was treated with Yangkyuksanhoa-tang(凉膈散火湯) and other treatments. Improvement in his general symptoms was observed.

• The Journal of Internal Korean Medicine
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• v.25 no.4
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• pp.401-409
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• 2004

Aphasia is a dysfunction in recognition and communication, Most instances of aphasia are caused by cerebral disease, especially when a dominant hemisphere is injured. It brings about serious problem in treatment and in directing a therapeutic course for return to social community. A stroke patient who was adimitted Dongguk Bundang Oriental hospital was treated. This subject was diagnosed with Broca Aphasia and Flaccid Tongue(舌?) induced by Yang-deficiency of Kidney(腎陽虛). She was adiministered Jiwhangeumja(地黃飮子) and Scalp acupuncture, and the degree of her aphsia was measured with the Western Aphasia Battery. After three weeks, The patient improved in speaking and general depressed condition.

• Analytical Science and Technology
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• v.18 no.4
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• pp.263-270
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• 2005

Nuclear track is an useful tool for elemental analysis of radionuclides, such as uranium, plutonium and thorium, etc., and for elements undergoing nuclear reactions with thermal neutrons such as lithium and boron. This method has various application fields such as detecting fissionable radionuelides, measuring the fission rate in nuclear technology, analyzing cosmic radiation from meteorite, calculating the age of minerals as well as their history, etc. Track registration method has been applied to the microscopic analysis of boron and fissionable element such as uranium in KAERI. This report reviews the theoretical background of the nuclear track formation, practical procedures to obtain etched tracks and a perspective of the future.

• Proceedings of the Korean Vacuum Society Conference
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• 2011.02a
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• pp.447-447
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• 2011

We studied to detect the mass variation using micro mechanical resonator. For measuring the resonance frequency of the micro mechanical system, optical method using laser interference is selected. A simple resonator is prepared by attaching an AFM cantilever on the piezo stack. The piezo stack makes a the cantilever vibrated with its resonance frequency. To change the mass of the resonator, gold was evaporated on the cantilever. We measured how much resonance frequency was changed according to the amount of gold attached on cantilever. This resonator is able to perform the role of a mass sensor and has a resolution of the order of micrograms. The fabrication of the resonator and measurement setup for detecting the mechanical resonance will be introduced in this presentation.

• Corrosion Science and Technology
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• v.10 no.4
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• pp.143-150
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• 2011

Copper electroplating has been applied to various fields such as decorative plating and through-hole plating. Technical realization of high strength copper preplating for wear-resistant tools and molds in addition to these applications is the aim of this work. Brighters and levelers, such as MPSA, Gelatin, Thiourea, PEG and JGB, were added in copper sulfate electrolyte, and the effects of these organic additives on the hardness were evaluated. All additives in this work were effective in increasing the hardness of copper electrodeposits. Thiourea increased the hardness up to 350 VHN, and was the most effective accelarator in sulfate electrolyte. It was shown from the X-ray diffraction analysis that preferred orientation changed from (200) to (111) with increasing concentration of organic additives. Crystallite size decreased with increasing concentration of additive. Hardness was increased with decreasing crystallite size, and this result is consistent with Hall-Petch relationship, and it was apparent that the hardening of copper electrodeposits results from the grain refining effect.

• Corrosion Science and Technology
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• v.10 no.4
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• pp.125-130
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• 2011

This study was performed to improve the corrosion resistance and the stability of passive film on copper tube by potentiostatic polarization method in synthetic tap water. Formation of passive film was carried out by anodic potentiostatic polarization at various passivation potentials and passivation times in 0.1 M NaOH solution. Stability of passive film and corrosion resistance was evaluated by self-activation time, ${\tau}_0$ from passive state to active state on open-circuit state in 0.1 M NaOH solution. Addition of polyphosphate in NaOH solution prolonged the self-activation time and improved the corrosion resistance, and the addition of 5 ppm polyphosphate was most effective. It was also observed that better corrosion resistance was obtained by potentiostatic polarization at 1.0 V (vs. SCE) than at any other passivation potentials. Passivated copper tube showed perfect corrosion resistance for the immersion test in synthetic tap water showing that the anodic potentiostatic polarization treatment in 0.1 M NaOH with 5 ppm polyphosphate solution would be effective in improving the corrosion resistance and preventing the blue water problem.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2015.10a
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• pp.63-64
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• 2015

In this paper, a microstrip array antenna capacitively coupled to a microstrip line is studied. The array antenna consists of uniformly spaced rectangular microstrip patches arranged close to a feeding microstrip line on a grounded dielectric substrate. The effects of various parameters, such as strip width and length, distance between adjacent patches, gap between strip patches and microstrip feed line, on the antenna performance were examined. By properly adjusting geometrical parameters, the array suitable for a high gain antenna for use in a frequency band centered at 12.5 GHz was designed.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.10
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• pp.2710-2723
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• 1996

2-dimensional scattering problem of electromagnetic waves by a periodic strip grating on a grounded dielectric slab in case of oblique incidence and arbitrary polarization is analyed by the vector Floquet modal expansion method. Solution convergence versus number of Chebyshev polynomial terms representing the unknown strip current density and number of space harmonics is examined, and some numerical results such as variation of power of significant space harmonics(scattered mode) are compared with those obtained by previous method. In particaluar, the relationship between Bragg blazing phonmena and characteristics mode(current) on the srip is discussed in detail.