• Environmental Analysis Health and Toxicology
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• 제20권3호
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• pp.237-242
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• 2005

This study il focused on the hepatopreventive effect in cirrhotic rats induced by N, N -dimethylnitrosamine treatment when organir Lulfur -containing compoundE were orally injected. Biochemical parameters (aspatate transaminase (AST), alanine transaminase (ALT) alkaline phosphatase (ALP), 1-protein and t-bilirubin) were measured in serum injured liver tissue. The increased AST and ALT values were significantly reduced by organic sulfur-containing compounds at the oral dotes of 50 mg/kg. The result of morphological changes have illustrated the accumulation of liver damages, Each as inflammatory cell accumulation and cirrhosis, caused by N, N-dimethylnitrosamine. Also, it was found that liver damages were prevented by the treatment of organic sulfur- containing compounds.

• Tribology and Lubricants
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• 제25권3호
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• pp.141-149
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• 2009

The effect of micro-cavities fabricated using laser surface texturing (LST) technique on polyoxymethylene (POM) surface was studied in terms of heat affected zone (HAZ), cavity geometry, surface roughness, deformation of cavity along with sliding cycles, and tribological characteristics. Cavity process parameters were lamp current, process time, and the stream of air used to minimize the flow of molten polymer into cavity. Especially, the deformation of cavity geometry was extensively studied to provide deep insight into morphological analysis of the cavities. Also, this paper presents the behavior of friction and wear of POM specimens as a function of sliding cycles.

• Transactions of Materials Processing
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• 제19권5호
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• pp.320-324
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• 2010

Multi-Layer Ceramic Circuit(MLCC) in the face of thousands of fine pitch multi hole is processed. However, the fine pitch multi hole has a size of only a few micrometers. Therefore, in order to curtail the measurement time and reduce error, the image processing measurement method is required. So, we proposed an image processing measurement algorithm which is required to accurately measure the fine pitch multi hole. The proposed algorithm gets image of the fine pitch multi hole, extracts object from the image by morphological process, and extracts the parameters of its position and feature by edge detecting process. In addition, we have used the sub-pixel algorithm to improve accuracy. As a result, the proposed algorithm shows 97% test-retest measurement reliability within 2 ${\mu}m$. We found that the algorithm was wellsuited for measuring the fine pitch multi hole.

• Textile Coloration and Finishing
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• 제19권4호
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• pp.38-46
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• 2007

Surface properties of the plasma treated fabric were changed while maintaining its bulk properties. Surface of plasma treated fabric take charge of enhanced adhesion by surface etching, surface activity. The water repellency coating Poly(Ethylene Terephthalate) fabric was treated with atmospheric pressure plasma using various parameters such as Argon gas, treatment time, processing power. Morphological changes by atmospheric pressure plasma treatment were observed using field emmission scanning electron microscopy(FE-SEM) and the zeta-potential measurement, contact angle measurement equipment. At the atmospheric pressure plasma treatment time of 150 sec, the power of 800W, the best wettability and peel strength were obtained. And we confirmed the possibility of industrial application by using atmospheric plasma system.

• Journal of The Korean Astronomical Society
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• 제13권1호
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• pp.45-62
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• 1980

Defining a metal parameter $(Sp)_c$, which is related to the morphological parameters of C-M diagrams, we have estimated metal abundances for 97 globular clusters in our Galaxy. A correlation between absolute magnitude of the horizontal branch and metal abundance is derived, which is used for the determining distances to globular clusters whose visual magnitudes of the horizontal branch are known. The space distribution of globular clusters and the chemical evolution of the halo are examined. Our analysis suggests an initial mean gradient of metallicity to be d[Fe/H]/$dr_G$ = -0.06 $kpc^{-1}$ for the halo in galactocentric distance, $r_G$<20 kpc. Our findings also imply a slow collapse of protogalaxy.

• The Bulletin of The Korean Astronomical Society
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• 제36권2호
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• pp.58.1-58.1
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• 2011

We present our N-body simulation study on the disk galaxy warp formation via close encounters. Using a publicly available code Gadget2, we investigate morphological and kinematical structures of disk galaxies while the galaxies are undergoing fly-by encounters with adjacent dark matter halos. In this study, we find that warps can be excited by impulsive encounters and sustained for a few billion years. Most of the warps from the simulation show inclination angles that are comparable to the observations. The creation of warps, their inclination and their lifetimes are governed primarily by the following three parameters: the impact parameter (the minimum distance between two halos), the mass ratio between two galaxies, and the incoming angle of the intruder. We discuss pros and cons about our alternative scenario in comparison with existing explanations.

• Journal of Industrial Technology
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• 제20권B호
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• pp.3-8
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• 2000

Low cycle fatigue life of spheroidal graphite cast iron is determined by the morphological parameters of internal graphite. The aim of this study is to clarify the effect of the number of nodular grain of spheroidal graphite cast iron on low cycle fatigue life. Two specimens that have identical average nodular grain size by changing nodular grain volume fraction and different number of nodular grain count was tested. In this paper, the parameter governing fatigue life through fatigue test, the number of nodular grain seriously affect fatigue life and nodular grain size is no longer governing parameter of it.

• KIEE International Transactions on Electrophysics and Applications
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• 제3C권6호
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• pp.241-245
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• 2003

ZnO thin films on (l00) p-type Si and sapphire substrates have been deposited by a pulsed laser deposition technique using an Nd:YAG laser with a wavelength of 266 nm. The influence of the deposition parameters such as oxygen pressure, substrate temperature and laser energy density on the properties of the grown films was studied. The experiments were performed for substrate temperatures in the range of 200∼50$0^{\circ}C$ and oxygen pressure in the range of 100∼700 sccm. All of the films grown in this experiment show strong c-axis orientation with (002) textured ZnO peak. With increasing substrate temperature, the FWHM (full width at half maximum) and surface roughness were decreased. In the case of using sapphire substrate, the intensity of PL spectra increased with increasing ambient oxygen flow rate. We investigated the structural and morphological properties of ZnO thin films using X-ray diffraction (XRD), scanning electron microscopy (SEM) and atomic force microscopy (AFM).

• Proceedings of the KIEE Conference
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• 대한전기학회 2000년도 하계학술대회 논문집 C
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• pp.1714-1716
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• 2000

We fabricated the optical system of merocyanine dye using Langmuir-Blodgett(LB) technique because quite uniform orientation could be obtained, which is one of the most important factors to affect to its optical characteristics. The resonance frequency and other electrical parameters at the parallel resonance state were measured using the impedance analyser(HP 4294 A). Also the morphological changes of dye molecules after UV irradiation were observed using AFM. The parallel resonance frequency and resistance by electrical equivalent circuit were decreased with the UV irradiation and these aspects are different from general mass adsorption process. Therefore the structural changes of dye molecules are being considered, that is, the aggregated molecules become dissociated. It indicates that the shifts of the resonance frequency and the others occurred without mass absorption.

• Proceedings of The Korean Society of Agricultural and Forest Meteorology Conference
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• 한국농림기상학회 2019년도 하계 학술발표초록집
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• pp.149-149
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• 2019