• Journal of Ocean Engineering and Technology
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• v.20 no.1 s.68
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• pp.48-54
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• 2006

In this paper, flowfield and acoustic-field around moving bodies are simulated by the Arbitrary Lagrangian Eulerian (ALE) formulation in the finite difference lattice Boltzmann method. Some effects are checked by comparing flaw about a square cylinder in ALE formulation and that in the fixed coordinates, and both agree very well. Matching procedure between the moving grid and fixed grid is also considered. The applied method in which the both grids are connected through buffer region is shown to be superior to moving overlapped grid. Dipole-like emissions of sound wave from harmonically vibrating bodies in two- and three-dimensional cases are simulated.

• Journal of the Korean Geotechnical Society
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• v.17 no.6
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• pp.85-98
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• 2001

Cone penetration was analyzed by arbitrary Lagangian-Eulerian(ALE) method. In order to simulate full penetration, steady state analyses were performed using ABAQUS/Explicit, which models upward flow of soil layers. In the analysis of homogeneous layer it was found that the paths and the strain of soil particles were consistent with the result of the strain path method and that the ultimate resistance were reasonably evaluated. The cone penetration through different soil layers was also analyzed and that showed the transfer of cone resistance. The steady state ALE analysis could perform full penetration through the layered soils.

• Microbiology and Biotechnology Letters
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• v.23 no.5
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• pp.544-549
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• 1995

The alkaline elastase is an extracellular serine protease of the alkalophilic Bacillus strain Ya-B. To increase the gene copy number and the production level of the alkaline elastase Ya-B, we designed, on the B. subtilis chromosome, a gene amplification of the 10.6 kb repeating unit containing amyE, aleE (alkaline elastase Ya-B gene) and tmrB. The aleE was inserted between amyE and tmrB, and B. subtilis APT119 strain was transformed with this amyE-aleE-tmrB-junction region fragment. As a result, we succeeded in obtaining tunicamycin-resistant (Tm$^{r}$) transformants (Tf-1, Tf-2) in which the designed gene amplification of 10.6 kb occurred in chromosome. The transformants showed high productivity of $\alpha $-amylase and alkaline elastase Ya-B. The copy number of the repeating unit (amyE-aleE-tmrB) was estimated to be 25, but plasmid vector (pUC19) was not integrated. The amplified aleE of chromosome was more stable than that of plasmid in absence of antibiotics.

• Proceedings of the Korean Society of Marine Engineers Conference
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• 2005.11a
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• pp.248-249
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• 2005

In this paper, flowfield and acoustic-field around moving bodies are simulated by the Arbitrary Lagrangian Eulerian (ALE) formulation in FDLBM. The effect of the ALE is checked by comparing flow about a square cylinder in ALE formulation and that in the fixed coordinates, and the results show good agreement. Matching procedure between the moving grid and fixed grid is also considered. The applied method in which the both grids are connected through buffer zone is shown to be superior to moving overlapped grid. Dipole-like emissions of sound wave from harmonically vibrating bodies in 2- and 3-dimensional cases are simulated.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.04a
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• pp.235-242
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• 2003

The solids and the fluids in porous media have a relative velocity to each other. Due to physically and chemically different material properties and their relative velocity, the behavior of saturated porous media is extremely complicated. Thus, in order to describe and clarify the deformation behavior of saturated porous media, constitutive models for deformation of porous media coupling several effects such as flow of the fluids or thermodynanical change need to be developed in frame of Arbitrary Lagrangian Eulerian (ALE) description. The aim of ALE formulations is to maximize the advantages of Lagrangian and Eulerian elements, and to minimize the disadvantages. Therefore, this method is appropriate for the analysis of porous media that are considered for the behavior of the solids and the fluids. In this work, governing equations of porous media based on ALE description are obtained from governing equations in frame of updated Lagrangian description. Then, weak forms of these equations are derived using arbitrary weighting functions.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.510-513
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• 2008

The traditional computational fluid or structure dynamics analysis approaches have contributed to solve many delicate engineering problems. But for the most of recent engineering problems which are influenced by fluid-structure interaction effect strongly, traditional individual approaches have limited analysis abilities for the exact simulation. Owing to above-mentioned reason, nowadays fluid-structure interaction analysis has become a matter of concern and interest. FSI analysis require several unprecedented techniques for the combining individual analysis tool into integrated analysis tool. The Arbitrary Lagrangian-Eulerian(ALE, in short) method is the new description of continum motion,which combines the advantages of the classical kinematical descriptions, i.e. Lagrangian and Eulerian description, while minimizing their respective drawbacks. In this paper, the ALE description is adapted to simulate fluid-structure interaction problems. An automatic re-mesh algorithm and a fluid-structure coupling process are included to analyze the interaction and moving motion during the 2-D axisymmetric solid rocket interior FSI phenomena simulation.

• Structural Engineering and Mechanics
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• v.16 no.4
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• pp.423-440
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• 2003

Arbitrary Lagrangian Eulerian finite element methods gain interest for the capability to control mesh geometry independently from material geometry, the ALE methods are used to create a new undistorted mesh for the fluid domain. In this paper we use the ALE technique to solve fuel slosh problem. Fuel slosh is an important design consideration not only for the fuel tank, but also for the structure supporting the fuel tank. "Fuel slosh" can be generated by many ways: abrupt changes in acceleration (braking), as well as abrupt changes in direction (highway exit-ramp). Repetitive motion can also be involved if a "sloshing resonance" is generated. These sloshing events can in turn affect the overall performance of the parent structure. A finite element analysis method has been developed to analyze this complex event. A new ALE formulation for the fluid mesh has been developed to keep the fluid mesh integrity during the motion of the tank. This paper explains the analysis capabilities on a technical level. Following the explanation, the analysis capabilities are validated against theoretical using potential flow for calculating fuel slosh frequency.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2011.04a
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• pp.748-751
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• 2011

일반적으로 물체의 거동을 해석하기 위해 고체영역에서는 Lagrangian 기법이 유체영역에서는 Eulerian 기법이 수치해석에 적용된다. Lagranian 기법은 서로 다른 물질의 경계와 자유표면에 대한 거동을 쉽게 추적할 수 있는 반면 물체의 대변형시 해석의 정확성이 떨어지는 단점이 있다. 또한 Eulerian 기법은 물질이동만을 고려하여 변형의 제한이 없는 장점을 가지고 있지만 이동하는 경계에 대해서 조건을 변화 시켜야하는 어려움이 있다. 따라서 이 두기법의 장단점을 서로 보안하기 위해 ALE(Arbitrary Lagrangian Eulerian)기법이 제안되었으며 이를 적용한 유체-구조물의 상호작용 해석에 대하여 많은 연구가 진행되고 있다. 본 논문에서는 이러한 ALE기법을 이용한 자유경계면에 대한 새로운 알고리즘이 제안된다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.21 no.7
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• pp.1833-1841
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• 1996

Recently, by emerging of the ALE techniques that make it possible to providereliable communications link automatically, high frequency communiation is newly used as emergency communication and back-up for satellite communications. ALE signal is transmitted in burst, and the received signal is subject to distortions by detrimental multipath fading channels. In the case of that channel, the performance of ALE system is highly dependent upon that of synchronization techniques. In this paper, M-ary FSK signals are detected by a bank of bandpass filter, which is implemented using recusive DFT(Discrete Fourier Transform). Also an acquisition and trancking algorithm are designed uisng parallel structure and early-late-gate methods respectively. Finally, we verify the performance ofthe proposed synchronization algorithm by the computer simulation.

• Journal of the Korean institute of surface engineering
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• v.23 no.4
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• pp.197-207
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• 1990

Atomic layer epitaxy is a relatively new epitaxial pprocess chracterized by the alternate and separate exposure of a susbstrate surface to the reactants contaning the constituent element of a compound semicoductror. The ideal ALE is expected to provide sevral advantageous as petcts for growing complicated heterostrutures such as relativly easy controls of the layer thinkness down to a monolayer and in forming abrupt heterointerfaces though monolayer self-saturatio of the growth. In addition, since ALE is stongly dependent on the surface reaction, the growth can also be controlled by photo-excitation which provides activation can be energies for each step of the reaction paths. The local growth acceleration by photo-excitation can be exploited for growing several device strures on the same wafer, which provides another important practical advantage. The ALE growth of GaAs has advanced to the point the laser opertion has been achieved from AlGs/GaAs quantun well structures where thee active layers were grown by thermal and Ar-laser assisted ALE. The status of the ALE growth of GaAs and other III-V compounds will be reviewed with respect to the growth saturation behavior and the electrical properties of the grown crystals.