• 대한기계학회:학술대회논문집
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• 대한기계학회 2008년도 추계학술대회A
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• pp.585-589
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• 2008

This study is performed to analyze the fluid flow about 150mm shower heads of semiconductor device. Under the air pressure, the ideal gas of moving fluid is injected as 5m/s velocity into inlet of shower heads and the flow distribution in shower heads is measured according to pitch of plasma distribution device. As results, the maximum and minimum value of fluid velocity are investigated with their position. The velocity values at outlet are also studied. From two experiment using the plasma distribution device, the results of CFD are compared with the experimental results. That results shows stable flow of fluid in that case of corrected design from CFD.

• 반도체디스플레이기술학회지
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• 제19권3호
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• pp.43-48
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• 2020

The demand for stable plasma has been on the rise because of the increased delivery power amount in the chamber for improving productivity, and fast and accurate plasma impedance matching become a crucial performance measure for radio frequency (RF) power system in semiconductor manufacturing equipment. In this paper, the overall impedance matching was understood, and voltage and current values were extracted with voltage - current (VI) probe to measure plasma impedance in real-time. Actual matching data were analyzed to derive calibration coefficient for V and I measurements to understand the characteristics of VI probe, and we demonstrated the tendency of RF impedance matching according to changes in load impedance. This preliminary empirical research can contribute to fast RF matching as well as advanced equipment control for the next level of detailed investigation on embedded system based-RF matching controller.

• 한국가시화정보학회지
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• 제17권1호
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• pp.53-59
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• 2019

Particle image velocimetry is performed in order to analyze flowfield induced by a dielectric barrier discharge plasma actuator. The velocity vector fields are obtained for the two different input voltage conditions; the voltage 3 and 5 kV at the frequency 10 kHz. The obtained flowfields show that the air is accelerated and its speed increase almost linearly over the covered electrode. The amount of momentum induced by the DBD plasma actuator is estimated from the obtained velocity fields, and the estimated values reasonably agree with the previous experiment.

• 분석과학
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• 제35권1호
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• pp.24-31
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• 2022

Herein, we present a simple, precise, accurate, and ultra-sensitive spectrofluorimetric method for estimation of clozapine (CLZ) in tablets and human plasma was developed and then validated. A highly fluorescent brown-yellowish fluorophore was formed (λ_ex=469 nm, λ_emi=540 nm) as a nucleophilic substitution reaction occurred between CLZ and 4-chloro-7-nitro-2,1,3-benzoxadiazole (NBD-Cl) in alkaline mcllavine buffer (pH 9.0). Optimum values of experimental parameters were carefully determined and optimized. The calibration curve was rectilinear over the concentration range of 80-900 ng mL^-1 with a linear correlation coefficient (r=0.9984). The LOD and LOQ were determined to be 14 ng mL^-1 and 42 ng mL^-1, respectively. The proposed approach has been used successfully to quantification of Clozapine in its commercial formulations and human plasma.

• Advances in Traditional Medicine
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• 제1권2호
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• pp.14-20
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• 2000

This study was designed to investigate the effect of dietary Platycodon grandiflorum on plasma glucose and lipid metabolism in $KK-A^y$ mice and STZ-induced diabetic rats. Both plasma triglyceride and plasma cholesterol levels in STZ-induced diabetic rats were significantly decreased by dietary Platycodon grandiflorum feeding for 4 weeks compared to those of control rats, but there were no marked differences in $KK-A^y$ mice. However, for plasma glucose values, Platycodon grandiflorum feeding resulted in a significant decrease in both STZ-induced diabetic rats and $KK-A^y$ mice. Also, dietary Platycodon grandiflorum slightly decreased the postprandial glucose level at 30 and 60 mins during oral glucose tolerance test in $KK-A^y$ mice. Although there was no statistical significance, the fasting plasma insulin levels of Platycodon grandiflorum dieted $KK-A^y$ mice tended to decrease when compared to that of control mice. Therefore, the present results suggested that dietary Platycodon grandiflorum may have a beneficial effect on preventing hypercholesterolemia and hyperlipidemia.

• Asian-Australasian Journal of Animal Sciences
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• 제23권1호
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• pp.131-148
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• 2010

Piglet health at weaning is compromised due to several stress factors. Following the ban of antibiotic growth promoters new alternatives are required to control these problems. This paper reviews the evidence available for the use of spray dried animal plasma (SDAP) as an alternative to antibiotics in weaning pigs. Data from 75 trials in 43 publications involving over 12,000 piglets (mean values) have been used to calculate the performance responses of piglets according to several factors including SDAP origin, protein source from the control diet being replaced, dose of inclusion, age and weight of the piglets at weaning, sanitary conditions and simultaneous use or not of medication. Although the use of SDAP of all origins results in positive responses, it appears that plasma from porcine origin has the highest efficacy. This could be explained by the specificity of its IgG against porcine pathogens. During the first week post-weaning the response to plasma appears to increase with the inclusion dose, although over the two-week pre-starter period an optimal inclusion level of 4-8% is suggested. SDAP improves feed efficiency more markedly when the piglets are challenged with an experimental infection or when feed does not contain medication, which could be indicative of a lower expenditure of energy and nutrients to build an immune response against the challenge. There is evidence supporting that SDAP IgG and other bioactive substances therein prevent the binding of pathogens to the gut wall and reduce the incidence of diarrhoea in the post-weaning phase. Overall, plasma can be postulated as an excellent alternative to in-feed antimicrobials for piglets in the post-weaning phase.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 춘계학술발표대회 논문집
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• pp.80-83
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• 2005

In this work, effects of oxygen plasma on surface characteristics of carbon fibers were investigated in mechanical properties interfacial of carbon fibers-reinforced composites. The surface properties of the carbon fibers were determined by acid/base values, FT-IR, and X-ray photoelectron spectroscopy (XPS). Also, the mechanical properties of the composites were studied in and critical stress intensity factor ($K_{IC}$) and critical strain energy release rate mode II ($G_{IIC}$) measurements. As experimental results, the $O_{lS}/C_{lS}$ ratio of the carbon fiber surfaces treated by oxygen plasma was increased compared to that of untreated ones, possibly due to development of oxygen-containing functional groups. The mechanical properties of the composites, including $K_{IC}$ and $G_{IIC}$ had been improved in the oxygen plasma on fibers. These results could be explained that the oxygen plasma was resulted in the increase of the adhesion of between fibers and matrix in a composite system.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2006년도 추계학술대회 논문집 Vol.19
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• pp.320-321
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• 2006

In this work, impedance Spectroscopic analysis was applied to study the effect of plasma treatment on the surface of indium-tin oxide (ITO) anodes using $CF_4g$ as and to model the equivalent circuit for organic light emitting diodes (OLEDs) with the $CF_4$ plasma treatment of ITO surface at the anodes. This device with ITO/TPD/$Alq_3$/LiF/Al structure can be modeled as a simple combination of a resistor and a capacitor. The $CF_4$ plasma treatment on the surface of ITO shifts the vacuum level of the ITO as a result of which the barrier height for hole injection at the ITO/organic interface is reduced. The Impedance spectroscopy measurement of the devices with the $CF_4$ plasma treatment on the surface of ITO anodes shows change of values in parallel resistance ($R_p$) and parallel capacitance ($C_p$).

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 추계학술발표대회 논문집
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• pp.23-26
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• 2005

In this work, effects of oxygen plasma on surfc1ce characteristics of carbon fibers were investigated in impact strength of carbon fibers-reinforced composites. The surface properties of the carbon fibers were determined by acid/base values, FT-IR, and X-ray photoelectron spectroscopy (XPS). Also, the mechanical properties of the composites were studied by impact strength measurements. As experimental results, the $O_{IS}/C_{IS}$ ratio of the carbon fiber surfaces treated by oxygen plasma was increased compared to that of untreated ones, possibly due to development of oxygen-containing functional groups. The mechanical properties of the composites, including impact strength had been improved by the oxygen plasma on fibers. These results could be explained that the oxygen plasma resulted in the increase of the adhesion of between fibers and matrix in a composite system.

• Journal of electromagnetic engineering and science
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• 제17권4호
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• pp.169-177
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• 2017

The role of electromagnetic (EM) waves in magnetic fusion plasma-ranging from radio frequency (RF) to microwaves-has been extremely important, and understanding of EM wave propagation and related technology in this field has significantly advanced magnetic fusion plasma research. Auxiliary heating and current drive systems, aided by various forms of high-power RF and microwave sources, have contributed to achieving the required steady-state operation of plasmas with high temperatures (i.e., up to approximately 10 keV; 1 eV=10000 K) that are suitable for future fusion reactors. Here, various resonance values and cut-off characteristics of wave propagation in plasmas with a nonuniform magnetic field are used to optimize the efficiency of heating and current drive systems. In diagnostic applications, passive emissions and active sources in this frequency range are used to measure plasma parameters and dynamics; in particular, measurements of electron cyclotron emissions (ECEs) provide profile information regarding electron temperature. Recent developments in state-of-the-art 2D microwave imaging systems that measure fluctuations in electron temperature and density are largely based on ECE. The scattering process, phase delays, reflection/diffraction, and the polarization of actively launched EM waves provide us with the physics of magnetohydrodynamic instabilities and transport physics.