• 한국해양학회지
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• v.30 no.4
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• pp.288-301
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• 1995

Rates of the sedimentation and particle mixing have been estimated by applying uranium-series disequilibrium techniques to three sediment cores collected from the korea Deep Ocean Study (KODOS) site between the clarion and Clipperton Fracture Zones (CCFZ) of the Equatorial Pacific. Sedimentation rates based on the profiles of excess /SUP 230/Th activity and /SUP 230/ Th/SUB xs//SUP 232/ Th activity ratios at the southeastern part of the study area were estimated to be in the order of a few millimeters per thousand year, while at the northwestern part a factor of ten lower. Excess activities of /SUP 230/Th and /SUP 230/Th ratios showed intervals of constant values in the upper part of the sediment cores, probably generated by biological particle mixing. A "two-box" advection-diffusion steady state mixing model was employed in order to estimate particle mixing rates in the upper and the lower layers, based on the distribution profiles of excess /SUP 210/Pb activities. Particle mixing coefficients were estimated to be in the order of 10$^1$ cm$^2$/y in the upper layer and 10/SUP -1/-10/SUP 0/ cm$^2$/y in the lower layer.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.46 no.3
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• pp.28-36
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• 2014

The kind and the mixing ratio of recovered papers would affect the quality of final recycled paper. In this study, effects of the mixing ratio of various domestic recycled papers (old news print (ONP), old corrugated container (OCC) and coated paper (CP)) on variations in physical properties of paper and its productivity were investigated. When the mixing ratio of CP grade increased, the freeness (CSF) of recycled pulp was increased while paper strength and white water turbidity was decreased. Paper strength was decreased as the percentage of OCC was higher than ONP. When ONP was mixed with OCC, no adverse effect was observed except the increased drainage resistance. It is expected that these results could be utilized as fundamental data to establish regulations for the recovered paper grades according to mixing ratios of different kinds of them.

• Clean Technology
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• v.28 no.4
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• pp.278-284
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• 2022

This study presents an excellent planar heater based on low-dimensional composites. By optimizing the ratio of 1D carbon nanotubes (CNT) and 2D MXene (Ti₃C₂T_X), it is possible to create a planar heater that has superior electrical conductivity and high heat generation characteristics. Low-dimensional composites were prepared by mixing CNT paste and MXene solution with eco-friendly waterborne polyurethane (WPU). In order to find the optimal mixing ratio for the MXene-CNT-WPU composites, samples with MXene to CNT weight ratios of 3:1, 1:1, 1:3, 1:7, and 1:14 were investigated. In addition to these different weight ratios, 5 wt% WPU was equally applied to each sample. It was confirmed that the higher the weight ratio of CNT, the lower the sheet resistance and the higher the heating temperature. In particular, when the MXene-CNT-WPU planar heater was fabricated by mixing MXene and CNT at a weight ratio of 1:7 and 1:14, the heating temperature was higher than the heating temperature of a CNT-WPU planar heater. These characteristics are due to the optimized mixture of the 1D materials (CNT) and the 2D materials (MXene) causing the formation of a flat surface and a dense network structure. The low-dimensional composites manufactured with the optimized mixing ratios found in this study are expected to be applied in flexible electronic devices.

• Journal of ILASS-Korea
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• v.11 no.4
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• pp.220-227
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• 2006

Experimental studies has been conducted to investigate the effect of orifice diameter ratio on the mixing characteristics of the split element of doublet and triplet elements. The spray characteristics of non-reacting immiscible liquids have been investigated using a patternator. The local volume fraction is measured by use of mean value of each component. This volume measurement represents the mixing characteristics of the liquid, which affect the overall combustion efficiency. The ratio of the orifice diameter, ranging from 1 to 1.5, and that of the jet-momentum, ranging from 0.5 to 6.0, we used. The jet impinging behavior with use of various ratios exhibits substantially different mixing characteristics. Mixing efficiency is maximized when the jet-momentum ratio is increased; this behavior is particularly prominent when the orifice diameter ratio is greater than unity. The split of the triplet element yields better mixing characteristics and is more effective than that of the doublet element in regard to achieving high combustion efficiency. The optimum mixing factor for the triplet element is found to be 0.75, according to our measurement.

• Journal of Advanced Marine Engineering and Technology
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• v.24 no.6
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• pp.120-127
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• 2000

This study is concerned with evaluating the effects of acoustic excitation on the development of two stream mixing layer generated by split plate. The ratios of two velocities U1 and U2 either side of the splitter plate were such that $U_1/U_2$=1.0 (uniform flow) or $U_1/U_2$<1.0(shear flow). The mixing layers were disturbed acoustically through the edge of split plate. Quantitative data were obtained with hot-wire anemometry. Flow visualization with smoke-wire was also employed for qualitative study. the results show that the large scale structures of mixing layers are strongly affected by excitation frequency and amplitude in both uniform and shear flows. The maximum streamwise and vertical turbulent intensities of the excited flow fields are apt to be decreased as compared with those of without excitation. The flow characteristics of uniform flow are more influenced by acoustic excitation than those of shear flow.

• Journal of the korean society of oceanography
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• v.33 no.3
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• pp.41-52
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• 1998

A seasonal circulation pattern in the eastern Yellow Sea (EYS) is suggested from the water mass analysis and geostrophic calculation using the hydrographic data collected by National Fisheries Research and Development Institute during the years of 1970 to 1990. This research focuses on the presence of inflow of warm (and saline) waters into EYS in summer. EYS is divided into two regions in this paper: the west coast of Korea (WCK) and the central Yellow Sea (CYS). In CYS, waters are linked with warm waters near Cheju Island in winter, but with cold waters from the north in summer (in the lower layer). It is not simple to say about WCK because of the influences of freshwater input and tidal mixing. Nevertheless, water mass analysis reveals that along WCK, waters have the major mixing ratios (40-60%) of warm waters in summer, while the dominant mixing ratios (50-90%) of cold waters in winter. Such a seasonal change of water mass distribution can be explained only by seasonal circulation. In winter, warm waters flow northward into CYS and cold waters flow southward along WCK. In summer, warm waters flow northward along WCK and cold waters flow southward into CYS. This circulation pattern is supported by both statistical analysis and dynamic depth topography. Accordingly, Yellow Sea Warm Current may be defined as the inflow of warm waters to CYS in winter and to WCK in summer.

• Journal of the korean Society of Automotive Engineers
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• v.13 no.2
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• pp.50-66
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• 1991

There are many factors which influence on the performance of a diesel engine. The piston bowl shape and swirl ratio are important factors to enhance the fuel-air mixing and flame propagation. In this study, calculations of the flow field in the cylinder of the diesel engine were carried out using the CONCHAS-SPRAY code for different bowl shapes and swirl ratios. In the case of constant swirl ratio, vortices which affect fuel-air mixing, evaporation and flame propagation are generated more strongly and consistently in the bowl-piston type combustion chamber than in the flat piston type. With this strong squish effect, injected fuel droplets are widely diffused and rapidly evaporated in the bowl-piston type combustion chamber. Especially a strong squish is developed and large and strong vortices are generated in the edge cutted bowl piston chamber. As the swirl ratio increases, it is found that a large and strong squish and vortices are generated in the combustion chamber and also fuel droplets are diffused into the entire combustion chamber.

• Korean journal of food and cookery science
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• v.15 no.3
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• pp.216-223
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• 1999

The purpose of this study is to find out the optimal mixing ratios of three different amounts of green tea powder, sugar and water for preparation of Sulgiduk through Response Surface Methodology based on the color, sensory, and texture test. The green tea powder levels were included 0.5∼1.0%, water levels were included 15∼25% and sugar levels were included 5∼15% per weight of rice powder. The optimal mixing ratios of a green tea powder, sugar and water for manufacturing the best quality of Sulgiduk were 1.0%, 12% and 22%, respectively.

• YAKHAK HOEJI
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• v.31 no.5
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• pp.343-346
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• 1987

The effect of mixing ratios of active ingredient on the content uniformity of tablets was studied using caffeine as active ingredient and hydroxypropyl starch as diluent. In the case that caffeine content was not more than 1%, the standard deviation of individual tablet assays was inversely proportional to caffeine content. In the case of more than 1%, the standard deviation was constant independently of caffeine content. In the case that the designed tablet weight was not more than 200mg, the standard deviation of individual tablet assays was inversley proportional to tablet weight designed. In the case of more than 200mg, it was constant and the results for weight variation against the designed weight showed same tendency.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 1997.11a
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• pp.286-289
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• 1997

It was studied that the effect of the mixing materials and the mole ratios on electrochemical properties of LiMn$_2$O$_4$LiMn$_2$O$_4$is prepared by reacting stoichiometric mixture of LiOH.$H_2O$ and MnO$_2$(EMD or CMD) and heating at 80$0^{\circ}C$ for 36h. We obtained properties of crystal structure through X-ray diffraction. LiMn$_2$O was reversible at 4.5V~3.0V and displayed two reduction and oxidation. Optimum synthesis results were obtained by reacting with LiOH.$H_2O$ and MnO$_2$(EMD) at mole ratio 1:2.