• Honam Mathematical Journal
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• v.41 no.3
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• pp.595-607
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• 2019

We consider quasigroups $Q({\Gamma})$ obtained as certain double covers of the symmetric group $S_3$ of degree 3, for directed graphs ${\Gamma}$ on the vertex set $S_3$. We completely characterize the strong compatibility of elements of $Q({\Gamma})$ for any quasigroup nonuniform homogeneous space of degree 4. For such homogeneous spaces, we classify all the strong and weak compatibility graphs of $Q({\Gamma})$.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.15 no.7
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• pp.1537-1542
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• 2011

In this paper, the subthreshold characteristics have been analyzed for various oxide thickness of double gate MOSFET(DGMOSFET) using Poisson's equation with nonuniform doping distribution. The DGMOSFET is extensively been studying since it can shrink the short channel effects(SCEs) in nano device. The degradation of subthreshold swing(SS) known as SCEs has been presented using analytical for, of Poisson's equation with nonuniform doping distribution for DGMOSFET. The SS have been analyzed for, change of gate oxide thickness to be the most important structural parameters of DGMOSFET. To verify this potential and transport models of thus analytical Poisson's equation, the results have been compared with those of the numerical Poisson's equation, and subthreshold swing has been analyzed using this models for DGMOSFET.

• Journal of Korea Water Resources Association
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• v.33 no.4
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• pp.385-392
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• 2000

An experimental investigation was conducted to determine the effect of a nonuniform pier on the stability of riprap placed around bridge piers. A nonuniform pier is one of which the cross-sectional dimension varies over the length of the pier and comprises a cylinder of diameter bp placed on a larger diameter of foundation bf. and the stability of riprap are significantly influenced by the height of foundation z. The critical height of foundation is defined as the height of foundation which has the same critical velocity to that of uniform pier without foundation, and it was found to be zc=0.8bf. For z

• Transactions of the Korean Society of Mechanical Engineers
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• v.13 no.5
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• pp.1012-1022
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• 1989

Numerical analysis has been performed on three-dimensional natural convection in inclined concentric annuli with the nonuniform temperature distribution of the inner cylinder. The governing equations are numerically solved by successive over-relaxation methods for various inclination angles at $R_{a}$=3*10$^{4}$, $P_{r}$=7.0 and $r_{1}$ / $r_{2}$=0.6. Temperature and Nusselt number distributions are obtained and calculated results are compared with those of published uniform temperature distributions. It is found that the mean Nusselt numbers for the nonuniform temperature distributions increase more than those for the uniform temperature distributions by about 9. 6% at .delta.= 0.deg., 7.5% at .delta. = 30.deg. and 4.6% at .delta. = 60.deg.. In the case of .delta. = 0.deg., the maximum local Nusselt numbers on the inner and outer cylinder walls show at .xi. = 0.5, 1.5 of .psio=100 .deg. and .xi. = 0.4, 1.6 of .psi. = 180 .deg.. But in the case of .delta. = 30.deg. and .delta. = 60.deg., the maximum local Nusselt numbers on the inner and other cylinder walls show at .xt. = 0.0 of .psi. = 180 .deg. and .xi. = 2.0 of .psi. = 180 .deg...

• Applied Science and Convergence Technology
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• v.24 no.5
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• pp.184-189
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• 2015

We report a simple way to enhance the size gradient of an imprinted nanopattern through oxygen plasma etching under a nonuniform magnetic field. A sample substrate was placed next to a magnet, and then a nonuniform magnetic field condition was formed around the sample. Using oxygen plasma etching, a line pattern having an initial width of 273 nm was gradually modified from 248 nm at one end to 182 nm at the other end. Controlling the arrangement of the magnet and sample, we could induce a triangular shape size gradient. We verified that the gradually modified nanopatterns we produced are applicable to continual optical property control, showing a possibility to be utilized for optical components such as gratings and polarizers.

• Applied Chemistry for Engineering
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• v.8 no.5
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• pp.872-879
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• 1997

The nonuniform thermal conductive reaction blocks were manufactured by impregnation of metal salts on the expanded graphite to improve the heat and mass transfer ability of reaction block for the chemical heat pump using the reaction of ammonia and metal salts(halide). The nonuniform blocks were designated to increase apparent density, like 165, 222, 279, 337, $394kg/m^3$ radially The experimental results showed that the heat transfer characteristics of nonuniform blocks were better than uniform blocks. As the reaction of ammonia repeated, the volumetric expansion in the reaction block makes the mass transfer improve, and the reproducibility better.

• Transactions of the Korean Society of Automotive Engineers
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• v.20 no.4
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• pp.133-141
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• 2012

This study investigates structural and fatigue analyses of bike brake. Maximum equivalent stress of the model of mountain bike is 4 times as much as the model of general bike at static analysis. In cases of mountain and general bikes, maximum damage frequency at load of 'SAE bracket history' with the severest change of load becomes as much as 16 times than the most stable load of 'Sample history' among the nonuniform fatigue loads. In case of mountain bike, the possibility of maximum damage becomes 3% at the load of 'Sample history' with the average stress of 0 to $-3{\times}10^4$MPa and the amplitude stress of 0 to $10^4$MPa. In case of general bike, the possibility of maximum damage becomes 3% at the load of 'Sample history' with the average stress of 0 to $-0.8{\times}10^4$MPa and the amplitude stress of 0 to $0.2{\times}10^4$MPa. This stress state can be shown as 5 to 6 times more than the damage possibility of 'SAE bracket history' or 'SAE transmission'. The analysis result of this study can be effectively utilized for the safe design of bike brake.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.16 no.12
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• pp.1131-1135
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• 2003

In the sintering of YIG, abnormal grain growth phenomena were observed. This abnormal grain growth is related to the sintering temperature in this experiment. In the sintering below 1450$^{\circ}C$, the sintered body showed narrow size distribution. However, in the sintering at 1450$^{\circ}C$, a few grains grew rapidly with respect to other grains, and bimodal size distribution was appeared. From the observation of the microstructure, liquid phase was not observed far from the abnormally grown large grains, but only near the large grains. This means that the abnormal grain growth was caused by the nonuniform distribution of liquid phase which promote the grains growth. Because the growth rate of grains near the liquid phase is much higher than that of the other grains, a few grains grow rapidly. This nonuniform distribution of liquid phase was thought to be due to the nonuniform mixing of the calcined powders. This abnormal grain growth was suppressed by enhancement of the compositional uniformity by multiple calcination.

• Journal of the Institute of Electronics and Information Engineers
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• v.51 no.3
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• pp.82-88
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• 2014

We study the effect of mesh reordering on Laplacian smoothing for parallel high performance computing systems. Specifically, we use the Reverse-Cuthill McKee algorithm to reorder meshes and use Laplacian Smoothing to improve the mesh quality on Nonuniform memory access architecture-based parallel high performance computing systems. First, we investigate the effect of using mesh reordering on Laplacian smoothing for a single core system and extend the idea to NUMA-based high performance computing systems.

• Proceedings of the KIEE Conference
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• 2008.07a
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• pp.1334-1335
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• 2008

Although many studies have been carried out about binary gas mixtures with $SF_6$, few studies were presented about breakdown characteristics of $SF_6/CF_4$ mixtures. At present study the breakdown characteristics of $SF_6/CF_4$ mixtures in uniform and nonuniform field was performed. The experiments were carried out under AC voltages. The sphere-sphere electrode whose gap distance was 1 mm was used and the point-plane electrode whose gap distance was 3 mm was used in a test chamber. $SF_6/CF_4$ mixture contained 20% $SF_6$ and 80% $CF_4$ and the experimental gas pressure ranged from 0.1 to 0.5 MPa. The results show that addition of $SF_6/CF_4$ mixtures increase AC breakdown voltages. In uniform field the breakdown voltages of gas were linearly increased according to the pressure. However in nonuniform field the breakdown voltages of gas were increased nonlinearly.