• Proceedings of the Optical Society of Korea Conference
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• 1990.02a
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• pp.79-81
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• 1990

Temperature distribution of laser diode chip mounted on ideal heat kink was calculated by numerical analysis. In numerical analysis, infinite difference method and Gauss-Scidel iteration was adopted on the basis of two dimensional heat conduction phenomena. As a result, temperature increase of active medium of laser diode driven at 60mA was calculated to be 1.47$^{\circ}C$

• Proceedings of the Korean Geotechical Society Conference
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• 2008.03a
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• pp.784-791
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• 2008

In this study, we recognized about application of the load distribution factor for design of tunnel in 3D numerical analysis. Generally, load distribution factor of tunnel is applied to describe 3D arching effect that can not describe when 2D numerical analysis. Through result of 3D numerical analysis, we used to apply in numerical analysis for the load distribution factor that ratio of finally displacement to displacement of construction step. But 3D numerical analysis need to apply to load distribution factor for convenience of numerical analysis. Therefore, we proposed load distribution factor that reduce time and coast. It corrected variable of advanced length in load distribution factor of 3D numerical analysis.

• Proceedings of the KSR Conference
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• 2011.10a
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• pp.337-342
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• 2011

Vehicle dynamic behavior should be investigated to establish the track irregularity criteria because they have an impact on vehicle dynamic behavior. The influence of twist on running behavior and safety for KTX was instigated by numerical analysis among track geometry quality parameters such as vertical alignment, lateral alignment, twist and track gauge in this paper. The wavelength and amplitude of twist were considered in scenario of this numerical analysis. This research is based on just numerical analysis and the final result which include measurement will be published in the future.

• Proceedings of the KSME Conference
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• 2001.06e
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• pp.136-141
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• 2001

In this study, we analysed tree surface flow by using the experimental and numerical method with a different surfactant concentration. We compared numerical solution with experimental results for one-dimensional model. The result shows that in general the tree surface velocity can well be reproduced by the one-dimensional model for various surfactant concentration.

• Water for future
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• v.17 no.3
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• pp.211-219
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• 1984

A 4-level baroclinic numerical model is designed by using the vorticity equation and Omega equation. Block-Cyclic-Reduction method is applied to the solution of the Helmholtz defferential equation, which is proved to be better than the Relaxation method from the composite viewpoint of accuracy, stability and economy. It was investigated whether the model explains the physical process influenced by voricity and temperature advection. It was also examined if the model atmosphere describes the general circulation. This examination is similar to Phillips(1956). The result of this numerical experiment shows that the model explains qualitatively the Quasi-Geostrophic theory for the development of Baroclinic wave, as throughly described in Holton(1972).

• Bulletin of the Korean Mathematical Society
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• v.44 no.1
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• pp.125-130
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• 2007

We propose a simple and intuitive method to derive the exact convergence rate of global $L_{2}-norm$ error for strong numerical approximation of stochastic differential equations the result of which has been reported by Hofmann and $M{\"u}ller-Gronbach\;(2004)$. We conclude that any strong numerical scheme of order ${\gamma}\;>\;1/2$ has the same optimal convergence rate for this error. The method clearly reveals the structure of global $L_{2}-norm$ error and is similarly applicable for evaluating the convergence rate of global uniform approximations.

• Journal of applied mathematics & informatics
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• v.26 no.5_6
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• pp.1123-1132
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• 2008

In this paper, by introducing a parameter, we establish a new Ostrowski's integral inequality which generalizes the result of [5]. Finally, we apply the new Ostrowski's inequality to numerical integration and special means.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2003.05a
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• pp.127-130
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• 2003

This paper presents the numerical thermal analysis for regeneratively cooled rocket thrust chambers. An integrated numerical model incorporates computational fluid dynamics for the hot-gas thermal environment, and thermal analysis for the liner and coolant channels. The flow and temperature fields in rocket thrust chambers is assumed to be axisymmetric steady state which is presumed to the combustion liner. The heat flux computed from nozzle flow is used to predict the temperature distribution of the combustion liner. As a result, we present the wall temperature of combustion liner and the temperature change of coolant.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.58-63
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• 2010

HEMU-400X train have been developed and will be operated over 350km/h. In this paper, the influence of vertical alignment on running behavior and safety for HEMU-400X train was instigated by numerical analysis. The wavelength and amplitude of vertical alignment were considered in scenario of this numerical analysis. This research is based on just numerical analysis and the final result which include measurement will be published in the future.

• Proceedings of the Korean Society For Composite Materials Conference
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• 2003.04a
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• pp.5-9
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• 2003

Stress and deflection of Active Fiber Composite(AFC) embedded and/or attached composite structures are numerically investigated at the constituent level by the Direct Numerical Simulation(DNS). The DNS approach which models and simulates the fiber and matrix directly using 3D finite elements need to be solved by efficient way. To handle this large scale problem, parallel program for solving piezoelectric behavior was developed and run on the parallel computing environment. Also, the stress result from DNS approach is compared with that from uniform field model.