• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.5
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• pp.31-36
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• 2007

Combustion performance characteristics of subscale high-pressure combustor were investigated at 70 bar combustion pressure. All tests were successfully performed without any damage on the combustor. The mixing characteristics and distribution pattern of the injectors were found to have considerable influence on the combustion performance. The characteristic velocity of the combustor was higher in the injector with internal mixing than that of external mixing and in the injector with smaller mass flowrate. The pressure fluctuations at the propellant manifolds and the combustion chamber were measured to be less than 3% of the mean combustion pressure to meet the combustion stability criterion and to prove stable combustion characteristics of the combustor.

• Journal of the Korean Ceramic Society
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• v.32 no.3
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• pp.289-294
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• 1995

As the results of the study on the effects of mixing time for raw materials to the electric and magnetic properties of Mg-ferrite, the fraction of spinel phase after calcination and the geometry density of sintered Mg-ferrite increased from 30% to 100% and from 2.5g/cc to 4.25g/cc respectively due to mixing-homobenity of raw materials. The AC resistivity of grains decreased and lattice parameter, saturation magnetization increased due to the increase in Fe+2 of sintered body. conclusively the characteristic of powder after calcination had strong influence on the microstructure, electric, and magnetic properties in Mg-ferrite sintered body.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.67 no.9
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• pp.1189-1196
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• 2018

7 type composites (40, 45, 50, 55, 60, 65, and 70 wt.%)were prepared for the environmentally friendly GIS Spacer. Five kinds of samples were prepared for optimization of the filler content ratio (MS: MA = 1: 9, 3: 7, 5: 5, 7: 3, 9: 1) of epoxy / microsilica and microalumina. As a result of evaluation of the partial discharge resistance characteristic, surface erosion is generally slowed down as the fill amount of micro silica is increased. Also, partial discharge resistance characteristics for the development of insulating materials with optimal mixing ratios of heterologous showed a higher partial resistance of discharge and a decrease in erosion, as the filler content ratio of micro silica was larger. In the future, various researches such as electrical, mechanical, and thermal studies will be needed to develop insulating materials that can commercialize power devices in environmentally friendly insulating gas.

• Preventive Nutrition and Food Science
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• v.5 no.4
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• pp.197-199
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• 2000

Clarified fruit and vegetable juices (apple, carrot and tangerine) were produced using ultrafiltration and their color change due to the mixing ratio were evaluated. clarification was carried out by passing he supernatant of extracted juice through a filter and also by using a membrane of molecular weight cut-off 10,000 Daltons to obtain the juice ultrafiltrates. The mixing ratio between apple and carrot juices was kept constant at 1:1 while increasing the amount of tangerine juice according to 10, 20, 30, 40 and 50% an stored at 4$^{\circ}C$ prior to the color measurement. Hue angle ({TEX}$h_{ab}${/TEX}) and {TEX}$L^{*}${/TEX}-value increased as the tangerine mixing ratio increased. The color difference indicated by ΔE-value also increased as the amount of tangerine increased indicating that the color of the mixed juice became pale and the changes were slight but distinctive. On the other hand, chroma ({TEX}$C^{*}${/TEX}), {TEX}$La{*}${/TEX}- and {TEX}$b^{*}${/TEX}-values decreased as the tangerine mixing ratio increased indicating that the color of the mixed juice became slightly more grayish and the samples were becoming les yellow. A simple mathematical model to predict each color characteristic is proposed.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.26 no.1
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• pp.133-140
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• 2002

This article presents an application of a large-scale structural mixing model(Broadwell et at. 1984) to the blowout of turbulent reacting cross flow jets. Experimental observations, therefore, aim to identify the existence of large-scale vortical structure exerting an important effect upon the flame stabilization. In the analysis of common stability curve, it is seen that the phenomenon of blowout are only related to the mixing time scale of the two flows. The most notable observation is that the blowout distance is traced at a fixed positions according to the velocity ratio at all times. Measurements of the lower blowout limits in the liftable flame are qualitatively in agreement with the blowout parameter $\xi$, proposed by Broadwell et al. Good agrement between the results calculated by a modified blowout parameter $\xi$'and the present experimental results confirms the important effect of large-scale structure in the stabilization feature of blowout.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.32 no.8
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• pp.574-581
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• 2008

The characteristics of combustion and flow for a lean premixed flame in lab-scale gas turbine combustor was studied through experiment and numerical analysis. From the experiment, flame structure and heat release rate were obtained from OH emission spectroscopy. Qualitative comparisons were made line-integrated OH chemiluminescence image and abel-transformed one. NOx analyzer was implemented to get the characteristic of NOx exhaust from the combustor. From the numerical analysis, the thermal distribution and characteristic of recirculation zone with the change of fuel-air mixing degree, the characteristic of methane distribution with equivalence ratio in the combustor respectively. Total heat release rate is increased with increasing equivalence ratio. Thermal Nox is reduced with increasing fuel-air mixing degree. Increasing equivalence ratio results in the decrease of the size of reaction zone and alteration of the position of the reaction zone into the entrance of the combustor.

• Korean Institute of Interior Design Journal
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• v.19 no.4
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• pp.58-65
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• 2010

The purpose of this study is to be applied with the basic data for the design method in the housing space which is differential. So, we analyzed the expression method and the application characteristic to materials of units in housing complex. To that, we researched on the condition of finishing material about the kind of material, color, texture and pattern for components in living room space. The results of this study are as follows : First, at the present time, the Object concept is expressed by 'mixing' and 'juxtaposition' of material, texture and pattern of finishing materials in housing space. But, we could find that the Object concept was used restrictively in housing space. So, we have to find different expression methods to be the effective and differential design by being applied Object concept for the housing space. Second, the 'mixing' which is the method to express the Object concept is showed in only 'art wall'. so, we can estimate that the method is the limited method to plan the varied housing. It is needed various expression methods to design components for the housing space. Third, it showed that the 'mixing' was a passive expression method using a little differential for design of housing space. We could estimate that similar methods were applied to the housing design. By results of this study, we can think that the develop study is needed to find design methods for expression of the Object in housing space.

• Journal of The Korean Society of Agricultural Engineers
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• v.55 no.3
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• pp.129-140
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• 2013

Bottom Ash is industrial by-product from a thermoelectric power plant. An immense quantities of bottom ash have increased each year, but most of them is reclaimed in ash landfill. In this study, in order to raise recycling rate of Bottom Ash, it is suggested to cure Bottom Ash (BA) mixtures mixed with cement, lime, Fly Ash (FA), and oyster shell (OS). Mixtures of 5~20 % mixing ratio had been cured for 1, 3, 7, 14, and 28 days using sealed curing and air-dry curing method. Unconfined compressive strength test was conducted to determine strength and deformation modulus ($E_{50}$) change for mixtures as mixing ratio and curing day, water contents of mixtures were measured after test. As a result, strength and $E_{50}$ were increased as mixing ratio and curing days, but values and tendencies of them appeared in different as kind of mixture, mixing ratio, curing method, and curing days. The results showed the addition of cement, lime, Fly Ash, and oyster soil in Bottom Ash could improved strength and $E_{50}$ and enlarge its field of being used.

• Journal of Power System Engineering
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• v.18 no.6
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• pp.126-132
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• 2014

The P-T characteristics of mixed refrigerant in thermostatic expansion valve sensing bulb were studied using R-134a and R-410A refrigerant. The characteristics of mixed refrigerant were investigated according to pressure variation and the variation of composition ratio of R-134A and R-410A in the temperature range of $-15^{\circ}C{\sim}15^{\circ}C$. The Thermodynamic characteristic values of the mixed refrigerants were identified using the characteristic value analysis program of mixed refrigerant(Refrop v9.0, NIST). The P-T characteristics in the case of the mixing ratio of 90:10 for R-410A and R-134A were the same result as R-22. And the physical properties showed similar results with R-22. The Maximum operating pressure(MOP) of mixed refrigerant showed a tendency to decrease with decreasing the mixing ratio of additive gases($N_2$ or He) gases. The characteristics in the case of the mixing ratio of 80:1 for mixed refrigerant and additive gases were the similar result as Reference refrigerant.(R-22 MOP, Sporlan company) In addition $N_2$ and He, both showed the same results. It was able to confirm that a MOP on the thermostatic expansion valve sensing bulb can be maintained by adjusting the mixing ratio of mixed refrigerant gases and additive gases.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.05a
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• pp.273-274
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• 2018

When IGCC Slag(CGS) aggregate was used as PHC-Pile, the moldability was lowered as the mixing ratio increased. concrete mix design. Also the mix characteristics increased the use of AD depending on the usage rate, however, require detailed consideration.