• Journal of the Korea Construction Safety Engineering Association
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• s.47
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• pp.56-62
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• 2008

In order to apply the Limit Equilibrium Method generally used for the slope stability analysis to the vertical excavation walls reinforced by soil-nailing, in this study, the Limit Equilibrium Method for the temporary shoring facilities reinforced by soil-nailing was proposed, which is based on the stability for the horizontal displacement. In this study, the relation of the internal friction angles of the ground and the vertical excavation depths was arranged, which is satisfying the stability on the horizontal displacement by using the verification of the Limit Equilibrium Method. And then, the rational reinforcing length of soil-nailing was proposed for the critical areas. In addition, the modified safety ratio satisfying the stability on the horizontal displacement was proposed, when the Limit Equilibrium Method was applied to the vertical excavation walls reinforced by soil-nailing.

• Journal of the Korea Institute of Military Science and Technology
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• v.23 no.4
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• pp.355-362
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• 2020

EFP composed of explosive, charge and liner generally penetrates standoff a target by Monroe effect. Its performance highly depends on penetrator characteristics and flight stability. Penetration ability can be dramatically reduced when the penetrator reaches the target with AOA, even if the penetrator has high kinetic energy and L/D ratio. Therefore, it is important to research not only penetrator characteristics and but also flight stability. In this work, the effect of liner shape on penetrator characteristics was examined using free flight test and numerical tools. It was found that tip velocity of penetrator was increased with decreasing liner thickness. It was also found that thicker liner had higher static margin leading to better flight status.

• Journal of Pharmaceutical Investigation
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• v.18 no.4
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• pp.181-186
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• 1988

Inclusion complex of sulfamethoxazole with ${\beta}-cyclodextrin$ was prepared by freeze-drying method in molar ratios of 1:1, 1:1.25, 1:1.5 and 1:1.75, and the complex formation was identified by ultraviolet and infrared spectroscopies, powder X-ray diffractometry and differential scanning calorimetry. Dissolution rate and solid state stability of the complex were investigated in comparison with those of sulfamethoxazole powder and the physical mixture of sulfamethoxazole with ${\beta}-cyclodextrin$. As a result, the dissolution rate and the stability of solid complexes in various relative humidity conditions increased more remarkably than those of sulfamethoxazole powder and physical mixture. But the difference according to molar ratio of the complex was not recognized.

• Journal of the Korean Society of Food Science and Nutrition
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• v.26 no.6
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• pp.1102-1108
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• 1997

Proteins and polysaccharides confer distinct functional properties in food systems. This research was attempted to improve emulsion properties of casein by protein-polysaccharide conjugation, in which alginates with various molecular weights were employed as polysaccharide sources. Casein-alginate mixtures were conjugated by the amino-carbonyl or Maillard reaction at 6$0^{\circ}C$ and 79% relative humidity. The resulting casein-alginate conjugates were tested for their emulsion activity and emulsion stabilizing properties. In general, the emulsion stability of casein-alginate mixture greatly increased due to the amino-carbonyl reaction between casein and alginates, whose magnitude depended on the molecular weight of alginate, weight ratio of casein to alginate and incubation time. It was also found that thermal stability and pH stability were markedly improved by the casein-alginate conjugation.

• Korean Chemical Engineering Research
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• v.57 no.5
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• pp.723-729
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• 2019

A theoretical analysis was conducted of convective instability driven by buoyancy forces under transient temperature fields in an annular porous medium bounded by coaxial vertical cylinders. Darcy's law and Boussinesq approximation are used to explain the characteristics of fluid motion and linear stability theory is employed to predict the onset of buoyancy-driven motion. The linear stability equations are derived in a global domain, and then cast into in a self-similar domain. Using a spectral expansion method, the stability equations are reformed as a system of ordinary differential equations and solved analytically and numerically. The critical Darcy-Rayleigh number is founded as a function of the radius ratio. Also, the onset time and corresponding wavelength are obtained for the various cases. The critical time becomes smaller with increasing the Darcy-Rayleigh number and follows the asymptotic relation derived in the infinite horizontal porous layer.

• Korean Chemical Engineering Research
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• v.57 no.3
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• pp.368-371
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• 2019

Using first principles calculations we investigated the thermomechanical stability of spent nuclear fuels (SNF), especially how mechanical properties of $UO_2$, such as, bulk, shear and Young's moduli and Poisson's ratio vary through alpha-decay of U into Th with generation of He gas. Our results indicate that substitution of U by Th through alpha decay ($U_{1-x}Th_xO_2$) does not significantly affect the stability of the grain in a fuel matrix. In addition, we studied the transport properties of He in and boundaries of the $U_{1-x}Th_xO_2$ grain. Helium preferentially resides at the grain boundaries through diffusion. Our study can contribute to substantial reduction of environmentally risk and enhancement of our sustainability by safe control of radioactive materials.

• The Journal of the Convergence on Culture Technology
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• v.10 no.1
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• pp.153-158
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• 2024

Recently, concerns about the spread of credit risk in China's real estate market are gradually increasing. Therefore, it is very meaningful to diagnose the management stability of Chinese commercial banks. This study analyzes the impact of housing prices on the loan proportion and management stability of Chinese commercial banks. In addition, we classify Chinese commercial banks according to size and verify whether there are differences in loan proportion and management stability. If there is a difference by scale, the effect of interaction with housing price changes is also verified. The analysis results are summarized as follows. First, it was found that as the housing price growth rate increases, the proportion of loans from Chinese commercial banks increases. Second, as the rate of increase in housing prices and the proportion of total loans increases, management stability appears to decrease. Third, larger banks were found to have a higher proportion of loans, and smaller banks were found to have greater management stability. The results of this analysis show that Chinese commercial banks' aggressive expansion of their loan proportion is lowering their management stability. Therefore, it is necessary to adjust the loan ratio to the appropriate size level and secure stability with differentiated strategies according to the loan ratio

• 한국연소학회:학술대회논문집
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• 2014.11a
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• pp.233-234
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• 2014

Lean-rich combustion system was composed both fuel-lean and fuel-rich flame at once. Each of fuel-lean and fuel-rich combustion types to reduce Thermal $NO_x$ and obtain flame stability. This study was confirmed a stability of flame through variation of flame shape that EGR was applied and compared the emission characteristics of EGR lean-rich combustion system to normal premixed combustion system at real condition to review a utility of the system. As a result, emission index of $NO_x$ and CO generated from EGR lean-rich combustion system at global equivalence ratio is 0.85 just half level($NO_x$ 0.31 g/kg, CO 0.08g/kg) compared to the amount generated from normal premixed combustion system at equivalence ratio is 0.78.

• Computers and Concrete
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• v.19 no.6
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• pp.677-687
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• 2017

The nonlinear buckling response of nano composite anti-symmetric functionally graded polymeric microplate reinforced by single-walled carbon nanotubes (SWCNTs) rested on orthotropic elastomeric foundation with temperature dependent properties is investigated. For the carbon-nanotube reinforced composite (CNTRC) microplate, a uniform distribution (UD) and four types of functionally graded (FG) distribution are considered. Based on orthotropic Mindlin plate theory, von Karman geometric nonlinearity and Hamilton's principle, the governing equations are derived. Generalized differential quadrature method (GDQM) is employed to calculate the non-linear buckling response of the plate. Effects of FG distribution type, elastomeric foundation, aspect ratio (thickness to width ratio), boundary condition, orientation of foundation orthotropy and temperature are considered. The results are validated. It is found that the critical buckling load without elastic medium is significantly lower than considering Winkler and Pasternak medium.

• Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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• 2008.04a
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• pp.31-32
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• 2008

The structure of OLEDs with conventional heterostructure consists of anode, hole injection layer, hole transport layer, light-emitting layer, electron transport layer, electron injection layer, and cathode. NPB used as a hole transport layer and DPVBi used as a blue light emitting layer were graded-mixed at selected ratio. Interface at heterojunction between the hole transport layer and the elecrtron transport layer restricts device's stability. Mixing of the hole transport layerand the emitting layer removes abrupt interface between the hole transport. layer and the electron transport layer. The stability of OLED with graded mixed-layer developed in this study was improved.