• 제목/요약/키워드: Plasma Simulation

검색결과 485건 처리시간 0.03초

개정된 생물학적 동등성 시험 기준에 대한 통계적 고찰 (Statistical consideration of assessing bioequivalence in the new KFDA regulation)

  • 고승곤;양지선;김정일;임남규
    • 응용통계연구
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    • 제15권2호
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    • pp.281-296
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    • 2002
  • 2000년도 의약분업으로 심화된 대체 조제에 대한 논란은 의사의 사전 동의 없이 대체조제 가능 품목을 식품의약품안전청장이 생물학적 동등성이 있다고 인정한 품목으로 제한함으로서 마무리되었다. 이에 발맞추어 식품의약품안전청(KFDA)은 후발 의약품에 대한 생물학적 동등성 시험 기준을 개정하였으며, 이 중에서 눈에 띄는 부분은 통계적인 고려 사항이다. 특히, 대조약과 시험약간의 동등성 판단을 위한 비교항목의 로그 변환을 명시한 것은 통계적 검증의 타당성 확보뿐만 아니라 국제적인 의약품 허가 추세에 부응한 바람직한 조치라 할 수 있다. 본 논문에서는 개정된 생물학적 동등성 시험 기준에서 고려 된 AUC와 Gmax의 로그 변환(log transformation)을 중심으로 그 배경과 통계적 의미를 고찰해 보고, 기존의 생물학적 동등성 판단 기준과 비교 검토해 보고자 한다. 또한 모의실험을 통해 개정된 기준의 통계적 타당성을 확인하고, 올바른 생물학적 동등성 판단을 위한 최소 표본수를 제안해 보기로 한다.

LM 가이드의 내마모성 향상을 위한 Me-DLC 코팅박막의 성능평가 (The Performance Test on Me-DLC Films for Improving Wear Resistance of LM-Guide)

  • 강은구;이동윤;김성영
    • 한국정밀공학회지
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    • 제29권4호
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    • pp.409-416
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    • 2012
  • Recently, surface modification technology is of importance to improve the wear resistance and the corrosive resistance for high accurate mechanical parts such as LM guide, Ball Screw and Roller Bearing etc., Those has generally featured on rolling contact mechanism to improve not only the wear and the friction, but also the accuracy and the corrosion performances. For surface modifications of high accurate mechanical parts, normally thermal spray, PVD, CVD and E.P. processes have been used with many materials such as DLC, raydent, W, Ni, Ti etc. Diamondlike carbon (DLC) films possess a combination of attractive properties and have been largely employed to modify the tribological behaviors such as friction, wear, corrosion, fretting fatigue, biocompatibility, etc. However, for rolling contact mechanism mechanical parts DLC films are needed to study for commercial benefit. Rolling contact mechanism has features on effects of cyclic motions and stresses, and also not simply sliding motions. The papers focused on the performance test of wear and corrosive resistance according to Me-DLC film thickness. And also, its thickness effect of wear analysis was carried out through the simulation of the maximum shear stress under the rolling contact surface. As the results, Me-DLC films have more potential to improve the wear resistance for high precision mechanical parts than raydent films.

플루르비프로펜 서방캅셀의 약물속도론적 평가 (Pharmacokinetic Evaluation of Flurbiprofen Sustained Release Capsule)

  • 박경호;이민화;양민열;이종원
    • Journal of Pharmaceutical Investigation
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    • 제23권3호
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    • pp.179-186
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    • 1993
  • In vitro dissolution test and pharmacokinetic study in human volunteers were conducted to evaluate the pharmacokinetic characteristics of 150 mg furbiprofen sustained-release capsule (FPSR-150). As a reference product, 50 mg flurbiprofen conventional-release capsule (FPCR-50) was used. Dissolution tests of two products were run using the paddle method in 450 : 540 (v/v %) mixture of simulated gastric and intestinal fluids (K.P. VI) by adjusting medium pH according to time. FPCR-50 was dissolved very rapidly, and it took about 1.5 hr for FPCR-50 to be dissolved over 90%, whereas 15 hr for FPSR-150. Also, in pharmacokinetic study, ten healthy male volunteers were administered one capsule of FPSR-150 or two capsules of FPCR-50 (FPCR-l00) with randomized two period cross-over study. Significant differences between FPCR-l00 and FPSR-150 were found in mean times to reach peak concentration, mean resident times and mean terminal phase halflives, while not in AUC/Dose (Student's t-test). In ANOVA for AUC/Dose to compare the bioavailabilities of two FP products, there was no significant difference. From the comparison of the simulated steady-state plasma concentration-time curves following multiple medications of FPCR-50 (3 capsules a day, dosing interval=8 hrs) and FPSR-150 (1 capsule a day) based on the above results obtained from single doses of two FP products, it was noted that the medication of FPSR-150 is more useful in clinical application rather than FPCR-50.

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Comparison analysis of superconducting solenoid magnet systems for ECR ion source based on the evolution strategy optimization

  • Wei, Shaoqing;Lee, Sangjin
    • 한국초전도ㆍ저온공학회논문지
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    • 제17권2호
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    • pp.36-40
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    • 2015
  • Electron cyclotron resonance (ECR) ion source is an essential component of heavy-ion accelerator. For a given design, the intensities of the highly charged ion beams extracted from the source can be increased by enlarging the physical volume of ECR zone [1]. Several models for ECR ion source were and will be constructed depending on their operating conditions [2-4]. In this paper three simulation models with 3, 4 and 6 solenoid system were built, but it's not considered anything else except the number of coils. Two groups of optimization analysis are presented, and the evolution strategy (ES) is adopted as an optimization tool which is a technique based on the ideas of mutation, adaptation and annealing [5]. In this research, the volume of ECR zone was calculated approximately, and optimized designs for ECR solenoid magnet system were presented. Firstly it is better to make the volume of ECR zone large to increase the intensity of ion beam under the specific confinement field conditions. At the same time the total volume of superconducting solenoids must be decreased to save material. By considering the volume of ECR zone and the total length of solenoids in each model with different number of coils, the 6 solenoid system represented the highest coil performance. By the way, a certain case, ECR zone volume itself can be essential than the cost. So the maximum ECR zone volume for each solenoid magnet system was calculated respectively with the same size of the plasma chamber and the total magnet space. By comparing the volume of ECR zone, the 6 solenoid system can be also made with the maximum ECR zone volume.

Triode magnetron sputtering system의 제작 및 특성평가 (Characteristic evaluations and production of triode magnetron sputtering system)

  • 김현후;이무영;김광태;윤상현;유환구;김종민;박철현;임기조
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2003년도 하계학술대회 논문집 Vol.4 No.2
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    • pp.787-790
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    • 2003
  • A rf triode magnetron sputtering system is designed and installed its construction in vacuum chamber. In order to calibrate the rf triode magnetron sputtering for thin films deposition processes, the effects of different glow discharge conditions were investigated in terms of the deposition rate measurements. The basic parameters for calibrating experiment in this sputtering system are rf power input, gas pressure, plasma current, and target-to-substrate distance. Because a knowledge of the deposition rate is necessary to control film thickness and to evaluate optimal conditions which are an important consideration in preparing better thin films, the deposition rates of copper as a testing material under the various sputtering conditions are investigated. Furthermore, a triode sputtering system designed in our team is simulated by the SIMION program. As a result, it is sure that the simulation of electron trajectories in the sputtering system is confined directly above the target surface by the force of $E{\times}B$ field. Finally, some teats with the above 4 different sputtering conditions demonstrate that the deposition rate of rf triode magnetron sputtering is relatively higher than that of the conventional sputtering system. This means that the higher deposition rate is probably caused by a high ion density in the triode and magnetron system. The erosion area of target surface bombarded by Ar ion is sputtered widely on the whole target except on both magnet sides. Therefore, the designed rf triode magnetron sputtering is a powerful deposition system.

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Experimental Demonstration of Enhanced Transmission Due to Impedance-matching Si3N4 Layer in Perforated Gold Film

  • Park, Myung-Soo;Yoon, Su-Jin;Hwang, Je-Hwan;Kang, Sang-Woo;Kim, Deok-kee;Ku, Zahyun;Urbas, Augustine;Lee, Sang Jun
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.359-359
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    • 2014
  • In this study, surface plasmon resonance structures for the selective and the enhanced transmission of infrared light were designed. In order to relieve the large discontinuity of refractive index between air and metal hole array, $Si_3N_4$ was used as the impedance matching layer. Experimental parameter were calculated and determined in advance by the rigorous coupled wave analysis (RCWA) simulation, and then the experiment was carried out. A 2-dimensional metal hole array structures were patterned on the size of $1{\times}1cm^2$ GaAs substrate using photolithography process, and 5 nm thick Ti, 50 nm thick Au were deposited by E-beam evaporator, respectively. Subsequently, $Si_3N_4$ films with various thicknesses (150, 350, 550, and 750 nm) were deposited by plasma enhanced chemical vapor deposition (PECVD). For the comparison, transmittance of specimens with and without $Si_3N_4$ was measured using Fourier transform infrared spectroscopy (FTIR) in the range of $2.5-15{\mu}m$. Furthermore, the surface and the cross-sectional images were collected from the specimens by scanning electron microscopy (SEM). From the results, it was demonstrated that the transmittance was enhanced up to 80% by the deposition of 750 nm $Si_3N_4$ at $6.23{\mu}m$. It has advantage of enhanced transmission despite the simple fabrication process.

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IT 모듈의 자유 낙하 모사를 위한 병렬처리시스템의 적용 (Application of Parallel Processing System for free drop simulation of IT-related modules)

  • 박영재;이준성;고한옥;장윤석;최재붕;김영진
    • 한국정밀공학회:학술대회논문집
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    • 한국정밀공학회 2006년도 춘계학술대회 논문집
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    • pp.405-406
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    • 2006
  • Recently, the flat display modules such as plasma or TFT-LCD employ thin crystallized panels which are normally weak to high level transient mechanical energy inputs. As a result, anti-shock performance is one of the most important design specifications for TFT-LCD modules. However, most of large display module designs are generated based on engineers own experiences. Also, a large-scale analysis to evaluate complex material and structural behaviors is one of interesting topic in diverse engineering and scientific fields. The utilization of massively parallel processors has also been a recent trend of high performance computing. The objective of this paper is to introduce a parallel process system which consists of general purpose finite element analysis solver as well as parallelized PC cluster. The parallel processing system is constructed using thirty-two processing elements and the finite element program is developed by adopting hierarchical domain decomposition method. In order to verify the efficiency of the established system, an impact analysis on thin and complex sub-parts of flat display modules is performed. The evaluation results showed a good agreement with the corresponding reference solutions, and thus, the parallel process system seems to be a useful tool fur the complex structural analysis such as IT related products.

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Numerical simulations of the vertical kink oscillations of the solar coronal loop with field aligned flows

  • Pandey, V.S.;Magara, T.;Lee, D.H.;Selwa, M.
    • 천문학회보
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    • 제36권2호
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    • pp.103.1-103.1
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    • 2011
  • Recent observations by Hinode show weakly-attenuated coronal loop oscillations in the presence of background flow (Ofman & Wang 2008, A&A, 482, L9). We study the vertical kink oscillations in solar coronal loops, considering field aligned flows inside the loops as well as surrounding the loops environment. The two dimensional numerical model of straight slab is used to explore the excitation and attenuation of the impulsively triggered fast magnetosonic standing kink waves. A full set of time dependent ideal magnetohydrodynamics equations is solved numerically taking into account the value of flow of the order of observed flows detected by SOT/Hinode. We find that relaxing the assumption of the limited flows within the loops enhances the damping rate of the fundamental mode of the standing kink waves by 2 - 3 % as compared to flow pattern which is basically localized within the loops. We further notice that extending the flow pattern beyond the loop thickness also enhances the strength of the shock associated with slow magnetoacoustic waves, recognized as an addition feature detected in the numerical simulation. The wider out-flow pattern destroys the oscillation patterns early as compared to narrower flow pattern, in other words we can say that it affects the durability of the oscillation. However, for the typical coronal loops parameters we find that the observed durability periods of the SOT/Hinode observation can be achieved with an out-flow Gaussian patterns for which half-width is not greater than factor 2.0 of the loop-half-width. explain a possible relation between electric current structure and sigmoid observed in a preflare phase.

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리팜피신캅셀의 생체내 이용율 (Relative Bioavailability of Commercially Available Rifampicin Capsules)

  • 신광범;조용백;송영준;곽효성;이민화
    • Journal of Pharmaceutical Investigation
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    • 제19권2호
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    • pp.93-98
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    • 1989
  • The study was performed to compare the dissolution, diffusion and absorption characteristics using Sartorius dissolution and absorption simulator and in vivo bioavailability of commercially available rifampicin capsules. Both brands C and F showed similar dissolution patterns and absorption properties through artificial gastric barrier in Sartorius simulator. Diffusion rate constants through the membrane of brands C and F were $3.04\;{\times}40^{-3}$ and $2.88\;{\times}\;10^{-3}cm/min$, respectively. Rifampicin capsules were administered orally to six fasted healthy volunteers according to cross-over design. The pharmacokinetic parameters between brands C and F, maximum plasma drug concentration$(C_{max})$, the time to reach $C_{max}$, absorption rate constant and area under the curve $(AUC_{0-24hr})$, elimination rate constant, and amount of drug excreted in urine were 6.11 and $7.27\;{\mu}g/ml$, 2.71 and 1.52 hr, 0.6371 and $1.6456 hr^{-1}$, 57.84 and $57.28\;{\mu}g\;{\cdot}\;hr/ml$, 0.1891 and $0.1734 hr^{-l}$, 119.98 and 119.93 mg, respectively. On the basis of experimental results, it was concluded that the bioavailability of brand C rifampicin capsules was almost the same as that of brand F rifampicin capsules.

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Enhancement of 1,3-Dihydroxyacetone Production from Gluconobacter oxydans by Combined Mutagenesis

  • Lin, Xi;Liu, Sha;Xie, Guangrong;Chen, Jing;Li, Penghua;Chen, Jianhua
    • Journal of Microbiology and Biotechnology
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    • 제26권11호
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    • pp.1908-1917
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    • 2016
  • Wild strain L-6 was subjected to combined mutagenesis, including UV irradiation, atmospheric and room temperature plasma, and ion beam implantation, to increase the yield of 1,3-dihydroxyacetone (DHA). With application of a high-throughput screening method, mutant Gluconobacter oxydans I-2-239 with a DHA productivity of 103.5 g/l in flask-shake fermentation was finally obtained with the starting glycerol concentration of 120 g/l, which was 115.7% higher than the wild strain. The cultivation time also decreased from 54 h to 36 h. Compared with the wild strain, a dramatic increase in enzyme activity was observed for the mutant strain, although the increase in biomass was limited. DNA and amino acid sequence alignment revealed 11 nucleotide substitutions and 10 amino acid substitutions between the sldAB of strains L-6 and I-2-239. Simulation of the 3-D structure and prediction of active site residues and PQQ binding site residues suggested that these mutations were mainly related to PQQ binding, which was speculated to be favorable for the catalyzing capacity of glycerol dehydrogenase. RT-qPCR assay indicated that the transcription levels of sldA and sldB in the mutant strain were respectively 4.8-fold and 5.4-fold higher than that in the wild strain, suggesting another possible reason for the increased DHA productivity of the mutant strain.