• KSCE Journal of Civil and Environmental Engineering Research
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• v.34 no.1
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• pp.167-173
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• 2014

The embedded suction anchor, ESA, is one type of mooring anchor systems which utilizes the suction pile or caisson to penetrate the anchor into the sea bed and develops its capacity under pullout load. In this study, the numerical analysis using ALE (Arbitrary Lagrangian Eulerian) Adaptive Meshing technique was performed to simulate the pullout behavior of the ESA, and the results were compared to those of the previous research, centrifuge model tests and the analytical method based on limit equilibrium theory. The pullout behaviors of the ESA under horizontal, vertical, and inclined loading were evaluated. The analysis results showed that the maximum horizontal pullout load was developed when the location of loading point was at the mid-point, and the each vertical pullout load gave the similar value regardless of the locations of the loading points. The pullout load decreased as the load inclination angle increased at the mid-point of the anchor.

• Journal of the Korean Society for Marine Environment & Energy
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• v.10 no.4
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• pp.218-226
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• 2007

In modern naval ships, the design of submarines has continually evolved to improve survivability and it is also important to design ship against shock response. Exiting underwater ship design has been peformed due to results of static analysis considering shock acceleration by simple method. However, it can not be anticipated good assesment. The present study applied the Arbitrary Lagrangian-Eulerian (ALE) technique, a fluid-structure interaction approach, to simulate an underwater explosion and investigate the survival capability of a damaged submarine liquefied oxygen tank. The Lagrangian-Eulerian coupling algorithm and the equations of state for explosives and seawater were also reviewed. It is shown that underwater explosion analysis using the ALE technique can accurately evaluate structural damage after attack. This procedure could be applied quantitatively to real structural design.

• Journal of Powder Materials
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• v.30 no.1
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• pp.53-64
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• 2023

Atomic layer etching (ALE) is a promising technique with atomic-level thickness controllability and high selectivity based on self-limiting surface reactions. ALE is performed by sequential exposure of the film surface to reactants, which results in surface modification and release of volatile species. Among the various ALE methods, thermal ALE involves a thermally activated reaction by employing gas species to release the modified surface without using energetic species, such as accelerated ions and neutral beams. In this study, the basic principle and surface reaction mechanisms of thermal ALE?processes, including "fluorination-ligand exchange reaction", "conversion-etch reaction", "conversion-fluorination reaction", "oxidation-fluorination reaction", "oxidation-ligand exchange reaction", and "oxidation-conversion-fluorination reaction" are described. In addition, the reported thermal ALE processes for the removal of various oxides, metals, and nitrides are presented.

• Korean Journal of Food Science and Technology
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• v.40 no.2
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• pp.238-242
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• 2008

In this study, hydrogen sulfide ($H_2S$) production was examined during beer fermentation using two ale and two lager yeast strains. In the lager yeast fermentation, a large amount of $H_2S$ was produced in the early fermentation stages when the yeast were actively fermenting wort, indicating a positive relationship between the level of H2S production and the yeast growth rate during fermentation. The ale yeasts produced much lower levels of H2S than the lager yeasts. In the lager fermentation, a higher fermentation temperature shortened the fermentation period, but much higher levels of $H_2S$ were produced at higher temperatures. American pilsner lager yeast fermenting at $15^{\circ}C$ produced a relatively high level of $H_2S$ at the end of fermentation, which would require a longer aging time to remove this malodorous volatile sulfur compound. Not including the English ale strain, which produced a higher level of H2S at lower temperatures, the ale yeast produced lower levels of $H_2S$ at lower temperatures, suggesting that each strain has an optimum fermentation temperature for H2S production.

• Food Science and Biotechnology
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• v.15 no.5
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• pp.752-755
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• 2006

This study was carried out to investigate the effects of ash tree leaf extract (ALE) on acetaminophen (APAP)-induced hepatotoxicity in mice. Hepatoprotective effects were detected by biochemical analysis of hepatic enzymes and histopathological examination of the liver. BALB/c mice were divided into three groups: 'normal' control mice, APAP-treated control mice, and mice pretreated with ALE and treated with APAP. A single dose of APAP markedly increased levels of plasma aspartate aminotransferase (AST) and alanine aminotransferase (ALT). Light micrographs of liver cells stained with hematoxylin and eosin showed that APAP induced severe centrilobular necrosis, degeneration, and infiltration by inflammatory cells. Moreover, APAP caused the numbers of TUNEL-positive hepatocytes to increase and caused glycogen content to decrease as observed by Periodic acid-Schiff stain. However, pretreatment with ALE for 7 days prior to the administration of APAP significantly decreased plasma levels of AST and ALT. Histological findings demonstrated that ALE pretreatment alleviated APAP-induced liver damage, and induced the regeneration of liver tissue and restoration of glycogen. These results indicate that ash tree leaf extract exerts a protective effect against APAP-hepatotoxicity induced injury.

• Journal of the Society of Naval Architects of Korea
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• v.42 no.4 s.142
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• pp.330-340
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• 2005

Compressible two-phase flow is analyzed based on the arbitrary Lagrangian-Eulerian (ALE) formulation. For water, Tamman type stiffened equation of state is used. Numerical fluxes are calculated using the ALE two-phase Godunov scheme which assumes only that the speed of sound and pressure can be provided whenever density and internal energy are given. Effects of the approximations of a material interface speed are Investigated h method Is suggested to assign a rigid body boundary condition effectively To validate the developed code, several well-known problems are calculated and the results are compared with analytic or other numerical solutions including a single material Sod shock tube problem and a gas/water shock tube problem The code is applied to analyze the refraction and transmission of shock waves which are impacting on a water-gas interface from gas or water medium.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2007.05a
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• pp.247-250
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• 2007

Flexible media such as the paper, the film, etc. are thin, light and very flexible. They behave in geometrically nonlinear. Any of small force makes large deformation. So we must including aerodynamic effect when its behavior is predicted. Thus, it becomes fully coupled fluid-structure interaction(FSI) problem. In FSI problems, where the fluid mesh near the structure undergoes large deformations and becomes unacceptably distorted, which drive the time step to a very small value for explicit calculations, the arbitrary Lagrangian-Eulerian(ALE) methods or rezoning are used to create a new undistorted mesh for the fluid domain, which allows the calculations to continue. In this paper, FE sheet model considering geometric nonlinearity is formulated to simulate the behavior of the flexible media. Aerodynamic force to the media by surrounding air is calculated by solving the incompressible Navier-Stokes equations. Q2Q1(Taylor-Hood) element which means biquadratic for velocity and bilinear for pressure is used for fluid domain. Q2Q1 element satisfies LBB condition and any stabilization technique is not needed. In this paper, cantilevered sheet in the viscous incompressible Navier-Stokes flow is simulated to check the mesh motion and numerical integration scheme, and then falling paper in the air is simulated and the effects of some representative parameters are investigated.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.23 no.1
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• pp.43-57
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• 1999

The fluid flow and heat transfer in a thin liquid film are investigated numerically. The flow Is assumed to be two-dimensional laminar and surface tension is considered. The most important characteristics of this flow is the existence of a hydraulic jump through which the flow undergoes very sharp and discontinuous change. Arbitrary Lagrangian-Eulerian(ALE) method is used to describe moving free boundary and a modified SIMPLE algorithm based on streamline upwind Petrov-Galerkin(SUPG) finite element method is used for time marching iterative solution. The numerical results obtained by solving unsteady full Navier-Stokes equations are presented for planar and radial flows subject to constant wall temperature or constant wall heat flux, and compared with available experimental data. It Is discussed systematically how the inlet Reynolds and Froude numbers and surface tension affect the formation of a hydraulic jump. In particular, the effect of temperature dependent fluid properties is also discussed.

• Journal of the Korean institute of surface engineering
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• v.24 no.1
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• pp.1-17
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• 1991

Understanding of the detailed reaction mechanisms during MOVPE and ALE is essential to further improve the properties of the grown crystals and the controllability of the growth parameters. The unified models for the detailed reaction paths are not available at this stage. The study, however, has been advanced to the extent that consensus on some of the reaction paths can be drawn from the scattered data. Metalakyls such as TMGa and TMIn seem to nearly fully decompose in the gas phase through homogeneous reaction at the typical MOVPE growth temperature. Hydrides such as AsH3 and PH3, on the contrary. seem to decompose heterogeneously onthe substrate surfaces as well as homogeneously in the gas phase. However, at lower temperatures, where ALE crystals are typically grown, the growth process is strongly dependent on the surface reactions. It seems that steric hindrance effects which the radicals reaching the substrate exhibit on the surface the growth rate a function of the metalalkyle supply durations. In addition, dydrogens released from hydrides seem to play an essential role in removing carbons leberated from the metalalkyls. High growth temperatures also seem to be effective in desorbing carbons from surface. The understanding of the reaction mechanisms was possible though diverse appraaches utilizing many ex-situ and in-situ diagnostic techniques and genuine experimental designs. It is the purpose of this paper to review and discuss many of these efforts and to draw some possible conclusions from them.

• Journal of the Korean institute of surface engineering
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• v.24 no.1
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• pp.1.1-1.1
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• 1991

Understanding of the detailed reaction mechanisms during MOVPE and ALE is essential to further improve the properties of the grown crystals and the controllability of the growth parameters. The unified models for the detailed reaction paths are not available at this stage. The study, however, has been advanced to the extent that consensus on some of the reaction paths can be drawn from the scattered data. Metalakyls such as TMGa and TMIn seem to nearly fully decompose in the gas phase through homogeneous reaction at the typical MOVPE growth temperature. Hydrides such as AsH3 and PH3, on the contrary. seem to decompose heterogeneously onthe substrate surfaces as well as homogeneously in the gas phase. However, at lower temperatures, where ALE crystals are typically grown, the growth process is strongly dependent on the surface reactions. It seems that steric hindrance effects which the radicals reaching the substrate exhibit on the surface the growth rate a function of the metalalkyle supply durations. In addition, dydrogens released from hydrides seem to play an essential role in removing carbons leberated from the metalalkyls. High growth temperatures also seem to be effective in desorbing carbons from surface. The understanding of the reaction mechanisms was possible though diverse appraaches utilizing many ex-situ and in-situ diagnostic techniques and genuine experimental designs. It is the purpose of this paper to review and discuss many of these efforts and to draw some possible conclusions from them.