• Journal of Ginseng Research
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• 제18권1호
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• pp.17-24
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• 1994

Effect of ginsenoside mixture, ginsenoside $Rb_1$,$Rb_2$,$Rg_1$ and the fat soluble fraction of the roots of Panax ginseng C.A. Meyer on the activity of glucokinase (GK) in vitro has been observed and found that GK activity was increased about 15c1c at the concentration of ginsenoside mixture and/or the fat soluble fraction being $10^{-7}$,$10^{-5}$%. It was also observed that glucose uptake by rat liver was increased in the presence of either ginsenoside mixture or the fat soluble fraction by perfusion technique. Ginsenoside mixture stimulated various enzymes related to glucose metabolism, however, both ginsenoside mixture and the fat soluble fraction did not stimulate GK activity as expected. Primary culture of liver cells showed that the ginsenoside mixture and the fat soluble fraction increased GK activity significantly and they stimulated the GK activity synergistically in the co-presence of insulin.

• 한국연소학회:학술대회논문집
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• 대한연소학회 2003년도 제27회 KOSCO SYMPOSIUM 논문집
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• pp.57-61
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• 2003

In the combustion modeling of non-premixed flames, the mixture fraction conserved scalar approach is widely utilized because reactants are mixed at the molecular level before burning and atomic elements are conserved in chemical reactions. In the mixture fraction approach, combustion process is simplified to a mixing problem and the interaction between chemistry and turbulence could be modelled by many sophisticated combustion models including the flamelet model and CMC. However, most of the mixture fraction approach is restricted to one mixture system. In this study, the flamelet model based on the two-feed system is extended to the multiple fuel-feeding systems by the two mixture fraction conserved scalar approach.

• 한국연소학회지
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• 제6권1호
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• pp.7-13
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• 2001

Propagation characteristics of tribrachial flames have been studied numerically in a two-dimensional fuel/oxidizer mixing layer. A flame is initiated by imposing a high temperature ignition source. Subsequent propagation of a tribrachial flame is traced. The flow redirection effect at the leading edge of a tribrachial flame increases the propagation speed beyond the corresponding stoichiometric laminar burning velocity. The effect of mixture fraction gradient on the propagation speed of a tribrachial flame is analyzed in a mixing layer considering that mixture fraction gradient increases as a tribrachial flame propagates toward upstream. As the flame curvature at the leading edge increases with decreasing mixture fraction gradient, the flow redirection effect becomes more pronounced on the flame propagation speed. As a result, the propagation speed of a tribrachial flame increases with decreasing mixture fraction gradient.

• 한국연소학회:학술대회논문집
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• 한국연소학회 2000년도 제20회 KOSCO SYMPOSIUM 논문집
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• pp.16-25
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• 2000

The differential diffusion of two species in jet is considered. The direct photo images of $H_{2}/SF_{6}$ flame are taken and the non-react jets of $H_{2}/SF_{6}$ mixture are visualized with Rayleigh scattering method. The structures of Dual flame are found in the photography. As the volume fraction of $H_2$ in mixture is increased, the flame at side is long and as the volume fraction of $SF_{6}$ in mixture is increased, the flame at center is long. This phenomena are deduced from the non-react mixture using Rayleigh scattering method. Result show that the volume fraction in the mixture is important in differential diffusion.

• 한국화재소방학회논문지
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• 제24권5호
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• pp.128-135
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• 2010

본 연구에서는 구획화재로부터 발생되는 화학종의 특성을 파악하기 위해서 혼합분율분석을 수행하였다. 메탄, 헵탄 그리고 톨루엔과 같은 탄화수소 연료들을 사용한 화재 실험이 ISO 9705 표준 화재실에서 수행되었으며 상층부의 두 지점에서 가스종 농도와 그을음(soot) 분율 등을 측정하였다. 미연탄화수소(UHC), 일산화탄소(CO), 이산화탄소($CO_2$), 산소($O_2$) 그리고 그을음 등의 측정된 화학종에 대한 질량분율을 혼합분율의 함수로 나타내었고, 탄화수소 연료의 이상적인 반응식에 기초한 상태 관계식과 비교 분석하였다. 혼합분율 분석은 다양한 화재 조건 및 측정 위치에서 얻은 수많은 측정데이터를 하나의 일관된 파라미터, 즉 혼합분율의 항으로 분류할 수 있게 하였다. 해석 결과를 통해 혼합분율 계산에 그을음을 고려하는 것이, 특히 헵탄이나 톨루엔과 같이 그을음 발생이 큰 연료의 경우 분석의 정확성을 향상시킴을 확인하였다.

• Nuclear Engineering and Technology
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• 제33권6호
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• pp.585-595
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• 2001

A series of experiments have been carried out to investigate the effects of non-condensable gas on the direct contact film condensation of vapor mixture under an adiabatic wall condition. The average heat transfer coefficient of the direct contact condensation was obtained at the atmospheric pressure with four main parameters ; air-mass fraction, mixture velocity, film Reynolds number, and the degree of water film subcooling having an influence on the condensation heat transfer coefficient. With the analysis of 88 experiments, a correlation of the average Nusselt number for direct contact film condensation of steam/air mixture at an adiabatic vertical wall was proposed as functions of film Reynolds number, mixture Reynolds number, air mass fraction, and Jacob number. The average heat transfer coefficient for steam/air mixture condensation decreased significantly while air mass fraction increased. The average heat transfer coefficients also decreased as the Jacob number increased, and were scarcely affected by the film Reynolds number below a mixture Reynolds number of about 245,000.

• 소성∙가공
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• 제8권4호
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• pp.399-406
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• 1999

It is more appropriate to treat that the semi-solid mixture as a single phase material that obeys incompressibility in the global sense and to analyze the liquid flow only locally than the approach based on compressible yield criteria. In the present study, a numerical algorithm of updating the solid volume fraction based on mixture theory has been developed. Finite element analysis of simple upsetting was carried out using the proposed algorithm to investigate the degree of macro-segregation according to friction conditions and compressive strain rates under the isothermal condition. The simulation results were compared to experimental results available in reference to test the validity of the currently proposed algorithm. Since the comparison results show a good agreement it is construed that the proposed algorithm can contribute to the development of numerical analysis of determining the solid volume fraction semi-solid processing.

• Asian-Australasian Journal of Animal Sciences
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• 제15권9호
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• pp.1307-1311
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• 2002

Twelve dietary combinations were prepared using 70 parts of fermented wheat straw (FWS) as the sole roughage supplemented with 30 parts of either the low protein concentrate mixture (Conc.-I), high protein concentrate mixture (conc.-II), maize grains (M), solvent extracted mustard cake (DMC), deoiled rice bran (DRB), uromol bran mixture (UBM), deep stacked poultry litter (DSPL), dried poultry droppings (DPD), M-DMC mixture (50:50), M-UBM mixture (50:50), M-DPD mixture (50:50) or M-UBM-DPD mixture (50:25:25) and evaluated by in-sacco technique. The above dietary combinations were also evaluated by changing the roughage to concentrate ratio to 60:40. The digestion kinetics for DM and CP revealed that FWS:DPD had the highest, whereas, the FWS:M-DMC had the lowest rapidly soluble fraction. The potentially degradable fraction was found to be maximum in FWS:M and minimum in FWS:DPD dietary combinations. The higher degradation rate of FWS:DRB and FWS:UBM combinations was responsible for their significantly (p<0.05) higher effective degradability as compared to other combinations. The highest undegradable fraction noted in FWS:M-UBM-DPD followed by FWS:DMC was responsible for high rumen fill values. The FWS:DRB, FWS:UBM and FWS:DPD combinations had higher potential for DM intake. The dietary combination with higher concentrate level (60:40) was responsible for higher potentially degradable fraction, which was degraded at a faster rate resulting in significantly higher effective degradability as compared to the corresponding dietary combination with low concentrate level (70:30). The low undegradable fraction in the high concentrate diet was responsible for low rumen fill values, which predicted of high potential for DM intake. Out of 24 dietary combinations, FWS with either of UBM, DRB, DMC, Maize, M-DMC or DPD in 70:30 ratio supplemented with minerals and vitamin A in comparison to conventional feeding practice (roughage and concentrate mixture) could be exploited as complete feed for different categories of ruminants.

• 미생물학회지
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• 제55권1호
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• pp.46-51
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• 2019

이 연구에서는 유칼립투스, 유카와 차나무의 ethanol 추출물의 수지를 이용한 분획 혼합물에 대한 항균활성을 평가하였는데 여러 인간 피부 상재균에 낮은 최소저해농도(0.24~3.32 mg/ml)를 나타내었고 항생제 triclosan과 ampicillin보다 우수한 활성을 나타내었다. Time kill assay에서 식물 추출분획 혼합물은 4시간 이내에 미생물 균주의 개체수를 92% 이상 감소시켰고, 모든 미생물 균주의 뉴클레오티드를 상당량 유출시켰으며, 항균 효과는 이가 양이온($Mg^{2+}$과 $Ca^{2+}$)에 영향을 받지 않았다. 이러한 결과는 Eucalyptus sp., Yucca sp., 및 tea tree의 ethanol 추출물의 수지분획 혼합물이 중요한 인간 피부 상재균을 억제하는 효율적인 화장품 방부제로 이용될 수 있음을 시사한다.

• 대한원격탐사학회:학술대회논문집
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• 대한원격탐사학회 2007년도 Proceedings of ISRS 2007
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• pp.468-470
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• 2007

This paper is to present an approach for generating coarse resolution (MODIS data) fraction images of forested region in Korea peninsula using forest type area fraction derived from high resolution data (ASTER data) in regional forest area. A 15-m spatial resolution multi-spectral ASTER image was acquired under clear sky conditions on September 22, 2003 over the forested area near Seoul, Korea and was used to select each end-member that represent a pure reflectance of component of forest such as different forest, bare soil and water. The area fraction of selected each end-member and a 500-m spatial resolution MODIS reflectance product covering study area was applied to a linear mixture inversion model for calculating the fraction image of forest component across the South Korea. We found that the area fraction values of each end-member observed from high resolution image data could be used to separate forest cover in low resolution image data.