• 한국안전학회지
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• 제18권1호
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• pp.71-75
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• 2003

The purpose of this study was to review the factors that influence on the combustion experiment of oxidizing solid such as mixing ratio of oxidizing solid and combustible support content ratio of oxidizing solid, ambient temperature, maturing time, combustible support, and additives. The 30g mixing compound samples of oxidizing solid and combustible support were tested with different mixing ratios. As a result, the Infest burning time was measured when mixing ratio was 4 (oxidizing solid) : 1 (combustible support). And the burning time was decreasing as the ambient temperature and maturing time were increasing.

• Elastomers and Composites
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• 제26권4호
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• pp.287-295
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• 1991

The mixing process with carbon black is important in the rubber industries. However, it is difficult to characterize the mixing mechanism of the carbon black. The mixing mechanism(distributive mixing and dispersive mixing) was discribed in this paper. The effect of fill factor on the mixing of the carbon black was studied. The dispersive mixing ability increases with increasing fill factor. However, the distributive mixing ability decreases with increasing fill factor. The effect of the carbon black content on the rheological property of the material was studied in this paper. The viscosity of the material increases with increasing the carbon black content. However, the elasticity of the matarial decreases with the carbon black content.

• 대한수학회논문집
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• 제37권4호
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• pp.1249-1258
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• 2022

In this study, we show that the strong exponential limit shadowing property (SELmSP, for short), which has been recently introduced, exists on a neighborhood of a hyperbolic set of a diffeomorphism. We also prove that Ω-stable diffeomorphisms and 𝓛-hyperbolic homeomorphisms have this type of shadowing property. By giving examples, it is shown that this type of shadowing is different from the other shadowings, and the chain transitivity and chain mixing are not necessary for it. Furthermore, we extend this type of shadowing property to positively expansive maps with the shadowing property.

• 한국복합재료학회:학술대회논문집
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• 한국복합재료학회 2005년도 추계학술발표대회 논문집
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• pp.125-128
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• 2005

The dispersion of carbon nanofiber (CNF) was carried out by solution blending, mechanical mixing, and sonication. CNFs at levels of 5-50% fiber weight content were mixed with polypropylene (PP) powder, and then were melt-mixed using a twin-screw extruder. For the further alignment of fibers, extruded rods were stacked uni-directionally in the mold cavity for the compression molding. For the evaluation of mechanical properties of nanocomposites, tension, in-plane shear, and flexural tests were conducted. CNF/PP composites clearly showed reinforcing effect in the longitudinal direction. The tensile modulus and strength have improved by 100% and 40%, respectively for 50 % fiber weight content, and the flexural modulus and strength have increased by 120% and 25%, respectively for the same fiber weight content. The shear modulus showed 65% increase, but the strength dropped sharply by 40%. However, the property enhancement was not significant due to the poor adhesion between fiber and matrix. In the transverse direction, the tensile, flexural, and shear strength decreased as more fibers were added.

• 한국재료학회지
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• 제14권9호
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• pp.659-663
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• 2004

Magnetite was prepared by wet method and oil-based magnetic fluid also was prepared by its magnetite. Ahead of making magnetite, we investigated the variation of physical properties for changing $Fe^{3+}/Fe^{2+}$. Through the variation of the process mixing time, pH, magnetite content, we made magnetic fluid of magnetite. We examined the magnetic and frequency property by a toroidal mold. In result $Fe^{3+}/Fe^{2+}=1.2$, over the minute mixing time property of magnetite, Ms was 61.98 emu/g. Moreover, the B-H loop result indicated that the magnetic fluid followed paramagnetic behavior.

• Communications for Statistical Applications and Methods
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• 제14권1호
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• pp.141-146
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• 2007

In this paper, we consider a Box-Cox transformed threshold GARCH(1,1) process and find a sufficient condition under which the process is geometrically ergodic and has the ${\beta}$-mixing property with an exponential decay rate.

• Communications for Statistical Applications and Methods
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• 제17권5호
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• pp.639-645
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• 2010

We consider a subdiagonal bilinear model and give sufficient conditions for the associated Markov chain defined by Pham (1985) to be uniformly ergodic and then obtain the $\beta$-mixing property for the given process. To derive the desired properties, we employ the results of generalized random coefficient autoregressive models generated by a matrix-valued polynomial function and vector-valued polynomial function.

• Communications for Statistical Applications and Methods
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• 제19권5호
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• pp.639-646
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• 2012

The exponential continuous time GARCH(p,q) model for financial assets suggested by Haug and Czado (2007) is considered, where the log volatility process is driven by a general L$\acute{e}$vy process and the price process is then obtained by using the same L$\acute{e}$vy process as driving noise. Uniform ergodicity and ${\beta}$-mixing property of the log volatility process is obtained by adopting an extended generator and drift condition.

• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2000년도 추계학술대회
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• pp.69-73
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• 2000

We systematically analyze the influence of fracture junction, solute transfer characteristics on transport patterns in discrete, two-dimensional fracture network models. Regular lattices and random fracture networks with power-law length distributions are considered in conjunction with particle tracking methods. Solute transfer probabilities at fracture junctions are determined from analytical considerations and from simple complete mixing and streamline routing models. For regular fracture networks, mixing conditions at fracture junctions are always dominated by either complete mixing or streamline routing end member cases. Moreover bulk transport properties such as the spreading and the dilution of solute are highly sensitive to the mixing rule. However in power-law length networks there is no significant difference in bulk transport properties, as calculated by assuming either of the two extreme mixing rules. This apparent discrepancy between the effects of mixing properties at fracture junctions in regular and random fracture networks is explained by the statistics of the coordination number and of the flow conditions at fracture intersections. We suggest that the influence of mixing rules on bulk solute transport could be important in systematic orthogonal fracture networks but insignificant in random networks.

• Korean Journal of Mathematics
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• 제3권1호
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• pp.107-114
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• 1995