• Transactions of the Korean Society of Automotive Engineers
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• v.10 no.3
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• pp.77-84
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• 2002

Measurements of NO and NOx emission of laminar partially premixed LPG/air flames with and without acoustic excitation are reported. The NOx emission at the tailpipe of a combustion chamber is determined by chemiluminescent analyser. The NOx measurements are taken in flames with several different center tube equivalance ratio( ø$\sub$o/), and overall equivalace ratio(ø$\sub$o/) for a fixed fuel flowrate. The NOx emission decrease to reach a minimum value at an optimum ø$\sub$c/ 2. Theø$\sub$c/ 2 flame gives a compromise of thermal NO and prompt NO mechanism. In the case of excitation. the visual shape of the flame is changed from laminar flame to turbulent-like flame. With increasing levels of excitation amplitude, an optimum value of the NO and NOx emission exists. A shorter flame caused by the enhanced upstream mixing due to acoustic excitation results in the reduction of NO and NOx emission in the present flames. The reduction of flame length affects the shorter residence time of center tube mixture, and significantly influences the NOx reduction.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.5 no.3
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• pp.216-223
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• 2000

In order to study origin and mixing ratio of surface water masses in the East China Sea (ECS), the South Sea of Korea and the Korea Strait, we use three end-member mixing equation. We use $^{228}$Ra/$^{226}$Ra activity ratio and salinity as two conservative tracer and the Changjiang Water (CW), the Yellow Sea Water (YSW), and the Kuroshio Water (KW) as three end members, Results show that ECS surface water includes all the three end member water, in the order of KW (50-90%), YSW (20-40%) and CW (0-20%) in August 1997. Also, the amount of CW can be approximately estimated by salinity alone. Surface water of the South Sea and the Korea Strait includes very small or almost no CW (below 2% except station 9) in May 1998. Thus in the Korea Strait mixing ratio could be estimated by $^{228}$Ra/$^{226}$Ra activity ratio tracer alone between two end-members, KW and YSW. However, in order to Set more accurate results or in case of rainy season, a mixing equation based on two tracers and three end-members is required.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2018.11a
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• pp.108-109
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• 2018

Cement is the most widely used but generates a lot of CO₂, so we need a material to replace it. Using industrial by-products such as Silica Fume(SF), Blast furnace Slag(BS) and Fly Ash(FA) bring some advantages including CO₂ reduction and resource recycling. However, there is a limit to improve performance when using only one material. Therefore, the synergy effects of No cement binary mortar and ternary mortar were analyzed and compared. As a result, No cement ternary mortar had the strength higher than binary mortar. among ternary mortars, the specimen mixed 50% of BS had the highest strength. However, when SF was mixed by 20%, the flowability reduces. so 10% of SF, 40% of FA and 50% of BS is considered as the optimal mixing ratio.

• Journal of the Korean Society of Combustion
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• v.12 no.2
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• pp.20-25
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• 2007

The supersonic combustion experiments are carried out using T3 free-piston shock tunnel. Hydrogen Fuel is injected in the cavity parallel with air(or nitrogen) flow. The equivalence ratios in this study are 0.132 and 0.447. Experimental measurements use OH-PLIF near the cavity and pressures in the combustor. For parallel fuel injection case, direct fuel add into cavity leads to increase of cavity pressure. And Flame exists just near the bottom wall for low equivalent ratio. There is no flame in the cavity because of no mixing in it. Compared to the inclined fuel injection, ignition delay length is longer for low equivalence ratio in both case. OH distribution is not a single line but a repeatable fluctuation flame structure by turbulence. Pressure distributions have nothing to do with the fuel injection position.

• Korean Journal of Materials Research
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• v.28 no.11
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• pp.615-619
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• 2018

To produce carbon electrodes for use in perovskite solar cells, electrode samples are prepared by mixing various weight ratios of 35 nm nano carbon(NC) and $1{\mu}m$ graphite flakes(GF), GF/(NC+GF) = 0, 0.5, 0.7, and 1, in chlorobenzene(CB) solvent with a $ZrO_2$ binder. The carbon electrodes are fabricated as glass/FTO/carbon electrode devices for microstructure characterization using transmission electron microscopy, optical microscopy, and a field emission scanning electron microscopy. The electrical characterization is performed with a four-point probe and a multi tester. The microstructure characterization shows that an electrode with excellent attachment to the substrate and no surface cracks at weight ratios above 0.5. The electrical characterization results show that the sheet resistance is <$70{\Omega}/sq$ and the interface resistance is <$70{\Omega}$ at weight ratios of 0.5 and 0.7. Therefore, a carbon paste electrode with microstructure and electrical properties similar to those of commercial carbon electrodes is proposed with an appropriate mixing ratio of NC and GF containing a CB solvent and $ZrO_2$.

• Korean Journal of Agricultural Science
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• v.47 no.4
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• pp.921-931
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• 2020

This study was carried out to determine the factor of a separating system according to the pepper varieties and the absence of a card cleaner system. The pepper varieties of Jeokyoung and AR-Legend were transplanted on November 20, 2019 and tested on March 18, 2020 with a harvesting speed of 0.2 m·s-1 for 10 pepper plants. The performance evaluation was determined by analyzing the separation efficiency of the peppers and the foreign matter mixing rate. The pepper harvester with a card cleaner showed a higher separation efficiency of the peppers compared to the pepper harvester without a card cleaner. The average separation efficiency of peppers on the pepper harvester with a card cleaner was higher at 13.5% for Jeokyoung and 1.9% for AR-Legend than that without a card cleaner. The mixing ratio of foreign materials on the pepper harvester with a card cleaner was lower at 8.7% and 2.5% for Jeokyoung and AR-Legend than that without a card cleaner, respectively. For the two-way ANOVA results according to the variety and the card cleaner, there was no effect on the separation efficiency of the peppers, but there was an effect on the foreign matter mixing rate.

• Journal of Information Display
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• v.11 no.2
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• pp.91-93
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• 2010

The shearing effects on the electro-optical properties of a stressed cholesteric liquid crystal were investigated. A photopolymer was dispersed in the cholesteric liquid crystal cell. By carefully choosing the mixing ratio between the liquid crystal and the photoreactive monomer, and by applying suitable mechanical shearing on the substrates, a cholesteric liquid crystal display with a low threshold voltage and no alignment layer was demonstrated.

• Journal of ILASS-Korea
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• v.2 no.1
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• pp.18-28
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• 1997

The present study is mainly aiming at numerically analyzing the combustion and emission characteristics of the diesel spray in a high-pressure environment. Computations are peformed for the peak chamber pressure with range from 4.08 MPa to 162 MPa. Numerical results indicate that the pressure increase in combustion chamber significantly influences the mechanism for droplet dynamics and mixing characteristics, spray penetration autoignition, flame lift-on height and the propagation or fuel vapor and flame. By increasing the ratio or the ambient density to injected liquid density, the fuel-air mixing rates and the burning rates increase and the $NO_x/soot$ emission level decreases.

• Animal cells and systems
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• v.8 no.4
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• pp.307-312
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• 2004

Fast kinetics of transient pH changes and difference spectrum formation have been investigated following mixing of ADP/ATP with partially purified plasma membrane PM-ATPase of the pathogenic yeast Candida albicans in the presence of five nutrients: glucose, glutamic acid, proline, lysine, and arginine and two analogs of glucose: 2-deoxy D-glucose and xylose. Average $H^+$- absorption to release ratio, indicative of population of ATPase undergoing complete hydrolytic cycle, was found to be 0.27 for control. This ratio varied between 0.25 (proline) to 0.36 (arginine) for all other compounds tested, except for glucose. In the presence of glucose, $H^+$- absorption to release ratio was exceptionally high (0.92). While no UV difference spectrum was observed with ADP, mixing of ATP with ATPase led to a large conformational change. Exposure to different nutrients restricted the magnitude of the conformational change; the analogs of glucose were found to be ineffective. This suppression was maximal in the case of glucose (80%); with other nutrients, the magnitude of suppression ranged from 40-50%. Rate of $H^+$- absorption, which is indicative of E~P complex dissociation, showed positive correlation with suppression of conformational change only in the case of glucose and no other nutrient/analog. Mode of interaction of glucose with plasma membrane $H^+$-ATPase thus appears to be strikingly distinct compared to that of other nutrients/analogs tested. The results obtained lead us to propose a model for explaining glucose stimulation of plasma membrane $H^+$-ATPase activity.

• Korean Journal of Construction Engineering and Management
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• v.1 no.2 s.2
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• pp.63-70
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• 2000

Since inorganic pigment, among admixtures used for cement composites, can raise the esthetic value of a building due to its effect of coloring, it can be assumed that the quantity consumed is expected to increase in connection with the recent trend of emphasizing the beautiful sights of the city. We carried out a flow test by changing the mix proportion of the cement mortar mixed with an inorganic pigment, water-cement ratio and pigment mixing ratio in order to present the basic materials for utilizing colored cement mortars. In construction by exploring the effect of inorganic pigments on the workability of cement mortar. In case of red pigment mortar and yellow pigment mortar, the workability was found to be rapidly decreased. To secure proper workability, it is necessary to increase the amount of mixing water, or to use superplasticizer. In case of green pigment mortar, however, it recorded $-2.4{\~}6.9{\%}$, showing that there was almost no change in flow. In case of black pigment mortar, it was also confirmed that there is no need to consider workability.