• 대한기계학회논문집B
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• 제27권3호
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• pp.381-388
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• 2003

An experimental study was carried out to measure the heat transfer coefficient in flow boiling to mixtures of HFC-l34a and HCFC-123 in a uniformly heated horizontal tube. Tests were run at a pressure of 0.6 MPa and in the ranges of heat flux 1-50 kw/$m^2$, vapor quality 0-100 % and mass velocity 150-600 kg/$m^2$s. Heat transfer coefficients of mixture were less than the interpolated values between pure fluids both in the low quality region where the nucleate boiling is dominant and in the high quality region where the convective evaporation is dominant. Measured data of heat transfer are compared to a few available correlations proposed for mixtures. The correlation of Jung et. al. satisfactorily predicted the present data, but the data in lower quality was overpredicted and underpredicted the high quality data. The correlation of Kandlikar considerably underpredicted most of the data. and showed the mean deviation of 35.1%.

• 대한기계학회논문집
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• 제16권9호
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• pp.1736-1743
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• 1992

본 연구에서는 기화기부착 4행정 4기통 전기점화기관을 사용하여 흡기관내 액 막흐름에 의한 연료의 불균일화가 기관의 연소특성과 배기특성에 미치는 영향을 규명 하는데 궁극적인 목적을 두고 우선, 연소특성을 해석하기 위하여 비교적 고가인 연소 해석 시스템을 개발하는데 1차적인 목적으로 하였으며, 시험제작한 연소해석 시스템으 로 액막흐름의 가시화 및 배기가스 농도측정과 지압선도 해석을 행하여 구조적으로 대 칭인 1번과 4번 실린더의 연소특성과 배기특성을 비교 검토하였다.

• 한국세라믹학회지
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• 제51권4호
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• pp.324-331
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• 2014

The dispersion characteristics of AlN-4.5 wt% $Y_2O_3$ powder mixture by various dispersants were investigated in ethanol and methyethly-ketone (MEK) solvents. In general, the cationic polymer dispersants demonstrated superior dispersion of the powder as compared to the non-ionic ester-type dispersants or anionic phosphate-ester-based ones. The dispersion performance of the cationic polymer dispersants was sensitive to the type of solvent. An anhydric maleic-acid-based graft copolymer dispersant, AFB-1521, demonstrated a very good dispersion capability in ethanol but exhibited a much inferior dispersion in MEK. On the other hand, the dispersion of the powder mixture was very good with a phosphate-ester-based block polymer dispersant, BYK-111, in MEK solvent, while dispersionwas much degraded in ethanol.

• Journal of Advanced Marine Engineering and Technology
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• 제26권2호
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• pp.209-218
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• 2002

The temperature field of a counterflow non-premixed flame is investigated using thermocouples of two sizes. A thermal balance is performed on the thermocouple in order to calculate the magnitude of the radiation corrections involved. Both the thermocouple wire and bead are separately considered to be the relevant thermal surface to which convective heat transfer takes place, and from which radiation lasses occur. The flame is also simulated by using a detailed chemical kinetic mechanism in a previously developed computer code. The local thermo-physical properties of the gas mixture, required to calculate the corrections, are determined both from the simulation, and by approximating the properties of the mixture as those of molecular nitrogen at the measured temperatures. It is concluded that the thermocouple wire is the appropriate thermal surface to which radiation corrections apply, in the absence of information about the gas mixture, its properties can be reasonably approximated by those of nitrogen rm ($N_2$), and the radiation corrections are very sensitive to misalignments in the temperature and velocity fields.

• 한국염색가공학회지
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• 제30권4호
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• pp.275-287
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• 2018

In recent years, research on the development of eco-friendly synthetic suede based on water-dispersed polyurethane resin and non-fluorine water repellent has been conducted. Synthetic suede has a problem that the fastness to dyeing is greatly lowered after the water-repellent processing at a high temperature of $160^{\circ}C$ because the polyester is dyed with a disperse dye. Therefore, in this study, silica was added to water-dispersed polyurethane resin to improve dye fastness. To distribute the $PUD-SiO_2$ mixture evenly in the water-dispersed polyurethane resin, sufficient stirring was done for a period of time. When the $PUD-SiO_2$ mixture(PUD 1-5%) is applied to the substrate, it is confirmed through SEM that the mixture is uniformly applied without particle condensation. The results showed that silica with a diameter of 4~12nm and BET of $200{\sim}380g/m^2$ had the ability to improve dispersibility and fastness.

• 대한예방한의학회지
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• 제19권1호
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• pp.117-130
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• 2015

Objective : This study was designed to investigate the effects of non fermented Zizyphus. jujuba mixture (mixed fruit and leaf : ZM) and fermented Z. jujuba mixture(FZM) on fed high-fat diet induced hyperlipidemic rats for development medicinal food. Method : The extracts prepared for Zizyphus. jujuba mixture(ZM) and fermented Z. jujuba mixture(FZM) with Lactobacillus plantarum and Saccharomyces cerevisiae. Experimental group was divided into normal control group(NC group) and high fat diet groups. The high fat diet groups fed high fat diet 2 weeks after was sub-divided into high fat diet control group(HC group), high fat diet positive control group(HPC group), non fermented Z. jujuba mixture extract group(ZM group) and fermented Z. jujuba mixture extract group(FZM group). NC and HC group was orally administerd of 0.9% saline, HPC group administerd lovastatin diluted in 0.9% saline at a dose of 10 mg/kg BW, ZM and FZM groups was administerd each extracts diluted in 0.9% saline at a dose of 300 mg/kg BW once a day on a fixed time for 4 weeks. In the present study we measured organ weight, epididymal fat tissue weight, concentration of serum lipids, hepatic lipids, MDA contents in liver tissue and metabolic variables in serum. Results : ZM and FZM suppressed testis weight loss and FZM decreased epididymal fat tissue weight to level of NC group in high-fat diets. ZM and FZM did not influence on serum cholesterol level, but prominently decreased serum triglyceride concentration compared with HC group, and FZM diminished hepatic triglyceride same as serum. ZM and FZM did not impair liver and kidney function and influence positive effects through by suppression of elevation lipid level. Conclusion : These results suggested that Z. jujuba mixture(ZM, FZM) should be useful developing medicinal food for prevention and improvement of hyperlipidemia and FZM is more suitable agent than ZM.

• Natural Product Sciences
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• 제5권1호
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• pp.7-11
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• 1999

A mixture of several bacterial metabolites $(Sterodin{\circledR})$ was used to study its effect on major immunocytes, in vivo and in vitro. This mixture of bacterial metabolites increased number of macrophages and neutrophils and their phagocytic activity in experimental animals for a transient period. BSA induced antibody production was found to be higher in the drug treated group. These results indicated that the bacterial metabolites probably acted through non-specific defence mechanism against invading organisms and the chance of reinfection was reduced.

• 한국막학회:학술대회논문집
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• 한국막학회 1991년도 추계 총회 및 학술발표회
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• pp.1-3
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• 1991

A novel membrane separation process for the separation of liquid mixture is Pervaporation. The term, 'pervaporation', is a combination of permeation and evaporation, and was first introduced by kober[1] in 1917. In this technique, the liquid mixture in feed is in contact with one side of a dense non-porous membrane and after diffusing through the membrane is removed from the downstream side in the vapor phase, but is usually condensed afterwards to obtain a permeate in liquid from.

• 한국CDE학회논문집
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• 제5권4호
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• pp.293-300
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• 2000

The non-manifold geometric modeling technique is to improve design process and to Integrate design, analysis, and manufacturing by handling mixture of wireframe model, surface model, and solid model in a single data structure. For the non-manifold geometric modeling, Euler operators and other high level modeling methods are necessary. Boolean operation is one of the representative modeling method for the non-manifold geometric modeling. This thesis studies Boolean operations of non-manifold model with the data structure of selective storage. The data structure of selective storage is improved non-manifold data structure in that existing non-manifold data structures using ordered topological representation method always store non-manifold information even if edges and vortices are in the manifold situation. To implement Boolean operations for non-manifold model, intersection algorithm for topological cells of three different dimensions, merging and selection algorithm for three dimensional model, and Open Inventor(tm), a 3D toolkit from SGI, are used.

• Asian-Australasian Journal of Animal Sciences
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• 제16권12호
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• pp.1732-1737
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• 2003

An experiment was conducted to investigate the effect of feeding transgenic cottonseed (Bt.) vis-a-vis non-transgenic (non-Bt.) cottonseed on blood biochemical constituents in lactating Murrah buffaloes. Twenty Murrah buffaloes in mid-lactation were divided into 2 groups of 10 each. Animals of group I were fed with 39.5% non-transgenic cottonseed in concentrate mixture while the same percentage of transgenic (Bt.) cottonseed was included in the concentrate mixture fed to the animals of group II. Animals of both groups were fed with concentrate mixture to support their milk production requirements. Each buffalo was also offered 20 kg mixed green fodder (oats and berseem) and wheat straw ad libitum. The experimental feeding trial lasted for 35 days. There was no significant difference in the dry matter intake between the two groups of buffaloes. All the buffaloes gained body weight, however, the differences were non significant. Total erythrocyte count, hemoglobin content and packed cell volume were $9.27{\pm}0.70${\times}10^6/{\mu}l$, $13.01{\pm}0.60gdl$ and $34.87{\pm}1.47%$, respectively in group I with the corresponding figures of $8.88{\pm}0.33$, $12.99{\pm}0.52$ and $31.08{\pm}1.52$ in group II. The values of total erythrocyte count, haemoglobin content and packed cell volume did not differ significantly between the two groups of buffaloes. The concentration of plasma glucose, serum total proteins, albumin, globulin, triglycerides and high density lipoprotein were non significantly higher in buffaloes fed non-transgenic cottonseed than in buffaloes fed transgenic cottonseed. The cholesterol concentration was significantly (p<0.01) higher in buffaloes of group I ($136.84{\pm}8.40mg/dl$) than in buffaloes of group II ($105.20{\pm}1.85mg/dl$). The serum alkaline phosphotase, glutamic-oxaloacetate transaminase and glutamic-pyruate transaminase activities did not differ significantly between two groups of buffaloes. However, serum glutamic-pyruate transaminase activity was considerably high in buffaloes fed nontransgenic cottonseed as compared to buffaloes fed transgenic cottonseed. Bt. proteins in serum samples of animals of group II were not detected after 35 days of feeding trial. It was concluded that transgenic cottonseed and non-transgenic cottonseed have similar nutritional value without any adverse effects on health status of buffaloes as assessed from haematobiochemical constituents.