• Proceedings of the KSME Conference
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• 2007.05b
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• pp.2731-2736
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• 2007

In this paper, incompressible flow over a cylinder near a plane wall using the Immersed Boundary. Finite Difference Lattice Boltzmann Method (IB-FDLBM) is implemented. In this present method, FDLBM is mixed with IBM by using the equilibrium velocity. We introduce IBM so that we can easy to simulate bluff-bodies. With this numerical procedure, the flow past a circular cylinder near a wall is simulated. We calculated the flow patterns about various Reynolds numbers and gap ratios between a circular cylinder and plane wall. So these are enabled to observe for vortex shedding. The numerical results are found to be in good agreement with those of previous studies.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.12 no.4
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• pp.1714-1729
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• 2018

Change detection of remote sensing images is a profound challenge in the field of remote sensing image analysis. This paper proposes a novel change detection method for bitemporal remote sensing images based on feature fusion and fuzzy c-means (FCM). Different from the state-of-the-art methods that mainly utilize a single image feature for difference image construction, the proposed method investigates the fusion of multiple image features for the task. The subsequent problem is regarded as the difference image classification problem, where a modified fuzzy c-means approach is proposed to analyze the difference image. The proposed method has been validated on real bitemporal remote sensing data sets. Experimental results confirmed the effectiveness of the proposed method.

• The Proceeding of the Korean Institute of Electromagnetic Engineering and Science
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• v.6 no.4
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• pp.11-19
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• 1995

In this paper, the Finite Difference Time Domain (FDTD) method is used to analyse the characteristics of the coaxial line transmission coefficent, shielding effectiveness, and compared to results of the moment method. The excitation mode of the Gaussian pulse is assumed to be a TEM-mode instead of the TE or TM-mode and in order to eliminate the reflected wave with in short length of the line. Calculated value of shielding effectiveness of the coaxial line by the FDTD are in good agreement with the results of the moment method.

• Journal of Advanced Marine Engineering and Technology
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• v.27 no.4
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• pp.511-519
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• 2003

A stratified flow is simulated using the finite difference lattice Boltzmann method (FDLBM). The effect of body force (gravity) in a simple one-dimensional model with the lattice BGK 9 velocity is examined. The effect of body force in the compressible fluid is greatly different from that of the incompressible fluid In a compressible fluid under gravitational force, the density stratification is not sufficient and the entropy stratification is essential. The numerical simulation of a line sink compressible stratified flow in two-dimensional channel is also carried out. The results show that selective withdrawal is established when the entropy of the upper part increases. and the simulated results using FDLB method are satisfactory compared with the theoretical one.

• Journal of the Korean Operations Research and Management Science Society
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• v.24 no.2
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• pp.53-68
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• 1999

This paper presents a nonparametric method to test if the mean difference of DEA efficiency estimates between two groups statistically exists. A proposed method employs a bootstrapping approach to generation BCC efficiency estimates through Monte Carlo simulation resampling process. For the purpose of demonstration, we empirically apply the proposed method to the korean bank industry and compare its result with the result by the traditional deterministic DEA method. The nonparametric statistical hypothesis testing procedure in this study, which considers not only stochastic variability of the DEA data, but also random radial deviations off the efficient frontier, serves as a useful tool for dbjectively evaluating whether the mean difference of DEA efficiency estimates between groups is statistically significant.

• Proceedings of the KIEE Conference
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• 1999.07f
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• pp.2632-2634
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• 1999

In this paper, we analyze the characteristics of Motor Noise according to PWM method, especially in the case of 2-phase conduction method. There are two types of PWM methods used usually. One is Lower-PWM and the other is Upper&Lower PWM. Because there is a difference between freewheeling path of both methods, Current profiles of two methods are different. This makes the difference of Torque Ripple and so difference of Noise Performance. In this paper, the path will be analyzed and the comparison of Noise performance of two types of PWM methods will be showed by experiment results.

• BMB Reports
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• v.30 no.4
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• pp.258-261
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• 1997

A simple quantitative assay method for ribonuclease activity has been developed. This method is based on the decrease of fluorescence intensity emitted by the ethidium bromide bound to RNA due to the degradation of RNA by ribonuclease. The substrate RNA was reacted with ribonuclease A and the fluorescence intensity was measured after the addition of ethidium bromide. The intensity difference was calculated using a blank reaction mixture containing no RNase. Whole cellular RNA substrate produced a significant error and was not suitable for this assay method possibly because of local microheterogeniety caused by high molecular weight rRNA. but satisfying results were obtained with tRNA substrate. The intensity difference increased linearly by raising enzyme concentration up to $2{\times}10^{-4}$ Kunitz Units of ribonuclease A. More refined and reliable results were obtained by use of initial reaction velocities which were calculated from the plots of intensity difference vs time. A linear relationship between initial velocities and enzyme concentrations was observed up to 0.01 Kunitz Units of enzyme.

• Proceedings of the Korea Society for Energy Engineering kosee Conference
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• 1993.05a
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• pp.60-63
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• 1993

The purpose of this study is to evaluate the difference in the solar rights between the suggested alternatives quantatively at the building design stage. To make the analysis method can be applied to any location, the solar rights analysis method utilizing Waldram diagram and solar rights table is suggested, and computerized for an accurate. quick and quantitative analysis. The solar rights analysis for two design alternatives was processed in accordance with the development of the analysis method. The results of the study are : 1) An algorithm to analyze the difference of the solar rights between two design alternatives with the classified codes, was developed. 2) A method to generate the solar rights table to evaluate the difference in solar rights, when two design alternatives was presented on the Waldram diagram was developed and computerized.

• 한국전산유체공학회:학술대회논문집
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• 1997.10a
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• pp.99-105
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• 1997

A finite-difference method based on conservative supra characteristic method type upwind flux difference splitting has been developed to study the nonequilibrium chemically reacting inviscid flow. For nonequilibrium air, NS-1 species equations were strongly coupled with flowfield equations through convection and species production terms. Inviscid nonequilibrium chemically reacting air mixture flows over Blunt-body were solved to demonstrate the capability of the current method. At low altitude flight conditions the nonequilibrium air models predicted almost the same temperature, density and pressure behind the shock as equilibrium flow: however, at high altitudes they showed substantial differences due to nonequilibrium chemistry effect. The new nonequilibrium chemically reacting upwind flux difference splitting mettled can be extended to viscous flow and multi-dimensional flow conditions.

• Journal of the Semiconductor & Display Technology
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• v.10 no.4
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• pp.95-100
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• 2011

This paper proposes a new method of vehicle brake lights detection and recognition using an R-filtering. Firstly, the proposed method processes the R-filtering with the first input image and then with the second one in order to detect brake lights. Secondly, the method counts the number of red pixels and computes the mean value in each R-filtered image. The difference rates between the numbers of the red pixels and between the mean values of two images are defined in this paper. Through the analysis of the difference rates, it can recognize whether brake lights are turned on or off, and whether the vehicle ahead is being approached or not. The proposed method is implemented using C language in an embedded Linux system for a high-speed real-time image processing. Experiment results show that the proposed algorithm is quite successful.