• Journal of applied mathematics & informatics
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• v.17 no.1_2_3
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• pp.73-91
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• 2005

The application of Green's function in calculation of flow characteristics around submerged and floating bodies due to a regular wave is presented. It is assumed that the fluid is homogeneous, inviscid and incompressible, the flow is irrotational and all body motions are small. Two methods based on the boundary integral equation method (BIEM) are applied to solve associated problems. The first is a low order panel method with triangular flat patches and uniform distribution of velocity potential on each panel. The second method is a high order panel method in which the kernels of the integral equations are modified to make it nonsingular and amenable to solution by the Gaussian quadrature formula. The calculations are performed on a submerged sphere and some floating spheroids of different aspect ratios. The excellent level of agreement with the analytical solutions shows that the second method is more accurate and reliable.

• Transactions on Electrical and Electronic Materials
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• v.17 no.5
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• pp.270-274
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• 2016

This article investigates the use of the Gaussian-channel doping profile for the control of the short-channel effects in the double-gate MOSFET whereby a two-dimensional (2D) quantum simulation was used. The simulations were completed through a self-consistent solving of the 2D Poisson equation and the Schrodinger equation within the non-equilibrium Green’s function (NEGF) formalism. The impacts of the p-type-channel Gaussian-doping profile parameters such as the peak doping concentration and the straggle parameter were studied in terms of the drain current, on-current, off-current, sub-threshold swing (SS), and drain-induced barrier lowering (DIBL). The simulation results show that the short-channel effects were improved in correspondence with incremental changes of the straggle parameter and the peak doping concentration.

• Journal of Electrical Engineering and Technology
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• v.4 no.2
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• pp.277-281
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• 2009

The complex resonant frequency problem of a superconductor patch is formulated in terms of an integral equation which is the kernel of a dyadic Green's function. To include the effect of the superconductivity of the microstrip patch, the surface complex impedance of the superconductor film is introduced using the two fluids model of Gorter and Casimir. The Galerkin procedure is used in the resolution of the electric field integral equation. Numerical results concerning the effect of the operating temperature of a superconductor patch on the characteristics of the antenna are presented.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.31 no.9
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• pp.764-771
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• 2007

The objective of the present work is to evaluate the evaporation heat flux of deposited droplet on the hot surface by using of inverse heat transfer technique. On the basis of measured temperature, a integral form solution is determined for the transient temperatures beyond the two positions by using Green's function technique. This method first approximates the temperature data with a half polynomial series of time. we compared this result with constant radius model in single phase regime, nucleate boiling regime, film boiling regime respectively. this paper performed the experiments as following conditions: (a)the surface temperature is within the range between $80^{\circ}C\;and\;160^{\circ}C$ in the conduction, (b) droplet diameter are 2.4 and 3.0mm. (c) surface roughness is $0.18{\mu}m$.

• Proceedings of the Korea Contents Association Conference
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• 2003.11a
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• pp.249-252
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• 2003

Scattering solutions of an H-plane T-junction in a parallel-plate waveguide are theoretically investigated. The iterative procedure and Green's function relation are used to obtain the iterative equations for the $E_{z}$ field modal coefficients, thus resulting in matrix solutions. The scattering characteristics of reflection and transmission powers are presented and compared with other existing results.s.

• Bulletin of the Korean Mathematical Society
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• v.54 no.2
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• pp.507-519
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• 2017

We present an upper bound on the Cheeger constant of a distance-regular graph. Recently, the authors found an upper bound on the Cheeger constant of distance-regular graph under a certain restriction in their previous work. Our new bound in the current paper is much better than the previous bound, and it is a general bound with no restriction. We point out that our bound is explicitly computable by using the valencies and the intersection matrix of a distance-regular graph. As a major tool, we use the discrete Green's function, which is defined as the inverse of ${\beta}$-Laplacian for some positive real number ${\beta}$. We present some examples of distance-regular graphs, where we compute our upper bound on their Cheeger constants.

• 한국정보디스플레이학회:학술대회논문집
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• 2005.07b
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• pp.1225-1228
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• 2005

Barrier ribs in the plasma display panel(PDP) function to maintain the discharge space between the glass plates as well as to prevent optical crosstalk. Patterning of barrier ribs is one of unique processes for making PDP. In this work photosensitive barrier rib pastes were prepared by incorporating binder polymer, solvent, functional monomers photoinitiator, and barrier rib powder of which surface was treated with fumed silica particles. Study on the function of materials for the barrier rib paste were undertaken. After optimization of paste formulation and photolithographic process, it was found that photolithographic patterning of barrier ribs with photosensitive barrier rib green sheet could be used in the fabrication of high resolution PDP.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.04a
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• pp.7-12
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• 2000

As the offshore oil fields are moved to the deep ocean, the oil production systems of FPSO(Floating production storage and offloading system) are building these days and so it is the most important to estimate the drift motion and damping effects the drift motion importantly. The components of damping consist of viscous, wave radiation effect and wave drift damping. It is need to estimate the wave drift damping exactly among them. The wave drift damping means the change rate of mean wave drift force with respect to the ship and ocean structures speed. In order to calculate this, the 3-Dimensional panel method used to translating and pulsating Green function is adopted. The calculation is carried out for series 60(CB = 0.7) vessel and the results are compared with other theoretical ones.

• Journal of the Korean Institute of Telematics and Electronics A
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• v.33A no.5
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• pp.75-84
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• 1996

planar circulator swith arbitrarily shaped ferrite resonators are analyzed in this paper. First, resonant frequencies and field distributions for the magnetized ferrite resonator are obtained using finite element method (FEM). Then the RF voltage distributions and other circuit parameters of the circulator which is formed by connecting three suitable transmission lines ot the ferrite resonator are derived from the green function . To remove the spurious solutions in analyzing the ferrite resonator, the results of eigenvalue analysis by node based FEM are comapred with the edge based fEM. The green function is expanded in terms of normalized eigenfunctions of th ecorresponding wave equation. Circulator parameters for circular disk resonator are clculated and compared with the analytical results. The experimental data for the designed circulator using hexagonal reosnator in the 850 MHz frequency range agree well iwth the simulated data.

• Proceedings of the KSME Conference
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• 2001.11a
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• pp.341-348
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• 2001

A Mixed Volume and Boundary Integral Equation Method is applied for the effective analysis of plane elastostatic problems in unbounded solids containing general anisotropic inclusions and voids or isotropic inclusions. It should be noted that this newly developed numerical method does not require the Green's function for anisotropic inclusions to solve this class of problems since only Green's function for the unbounded isotropic matrix is involved in their formulation for the analysis. This new method can also be applied to general two-dimensional elastodynamic and elastostatic problems with arbitrary shapes and number of anisotropic inclusions and voids or isotropic inclusions. Through the analysis of plane elastostatic problems in unbounded isotropic matrix with orthotropic inclusions and voids or isotropic inclusions, it will be established that this new method is very accurate and effective for solving plane elastic problems in unbounded solids containing general anisotropic inclusions and voids or isotropic inclusions.