• Structural Engineering and Mechanics
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• v.5 no.6
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• pp.775-784
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• 1997

A unified theory is presented for the shape analysis of curved surface with a single layer structure composed by frame, membrane or shell. The shapes produced by the theory have no shear stress in elements, and the stress states in the whole shape are as uniform as possible under an ordinary load. The theory starts from defining an element potential function expressed by the measurement of the element length or the element area. Therefore, the shape analysis can produce various forms according to the definition of the potential function, and each of those form or the cable net form with the potential function of the second power of element length is simply gotten by the linear analysis. The form in tensile stress is mechanically equal to an isotropic tension form.

• 한국전산유체공학회:학술대회논문집
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• 2006.10a
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• pp.61-65
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• 2006

This paper describes a recent development on the divergence free basis function based on a hermite stream function. The well-known cavity problem has been used to compare the accuracy and the convergence of the present method with those of a modified residual method known as one of the stabilized finite element methods. The comparison showed the present method performs better in the accuracy and convergence.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2006.11a
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• pp.411-414
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• 2006

This paper describes a recent development on the divergence free basis function based on a hermite stream function. The well-known cavity problem has been used to compare the accuracy and the convergence of the present method with those of a modified residual method known as one of the stabilized finite e1ement methods. The comparison showed the present method performs better in the accuracy and convergence.

• Journal of the Korean earth science society
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• v.25 no.2
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• pp.109-114
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• 2004

A wavelet method is applied to the analysis of gravity potential. One scaling function is proposed to generate wavelet. The scaling function is shown to be replaced to the Green’s function in gravity potential. The upward continuation can be expressed as a wavelet transform i.e. convolution with the scaling function. The scaling factor indicates the height variation. The multiscale edge detection is carried by connecting the local maxima of the wavelet transform at scales. The multiscale edge represents discontinuity of the geological structure. The multiscale edge method is applied to gravity data from Masan and Changwon.

• Journal of Advanced Research in Ocean Engineering
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• v.2 no.1
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• pp.12-21
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• 2016

In this paper, the $2^{nd}$ order hydrodynamic force effect of heaving submerged circular cylinder is considered, with the linear potential theory. Boundary value problem (BVP) is expanded up to the $2^{nd}$ order by using of the perturbation method and the $2^{nd}$ order velocity potential is calculated by means of integral equation technique using the classical Green's function expressed in cylindrical coordinates. The method of solving BVP is based on eigenfunction expansions. With different cylinder heights and heaving frequencies, graphical results are presented. As a result of the study, the cause of oscillatory force pattern is analyzed with the occurrence of negative added mass when a top of the cylinder gets closer to the free surface.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.19 no.12
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• pp.2418-2425
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• 1994

Although the error backpropagation(EBP) algorithm based on the gradient descent method is a widely-used learning algorithm of neural networks, learning sometimes takes a long time to acquire accuracy. This paper develops a novel learning method to alleviate the problems of EBP algorithm such as local minima, slow speed, and size of structure and thus to improve performance by adopting other new networks. Gaussian Potential Function networks(GPFN), in parallel with multilayer neural networks. Empirical simulations show the efficacy of the proposed algorithm in function approximation, which enables us to train networks faster with the better generalization capabilities.

• Nuclear Engineering and Technology
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• v.5 no.2
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• pp.77-82
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• 1973

A method of obtaining the partition function for a system of electrons is developed by defining a new density matrix, in which the Fermi statistics is explicitly incorporated. The corresponding Bloch equation is formulated and a practical method of solving the equation is obtained for weak potential. This theory is applied to structurally disordered ststems which might be reasonable models for liquid metals.

• Proceedings of the KIEE Conference
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• 1996.07a
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• pp.154-156
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• 1996

A new method for electric resistivity tomography(ERT) is developed for geophysical inverse problems by adapting the sensitivity analysis. The outputs of the potential electrodes are computed using two dimensional finite element method in the wave number space by Fourier transforming the governing equations. The resistance distribution in the region of interests, which makes the computed potential distribution coincide with the measured potential, is found by minimizing the objective function using an optimization method. In this process the sensitivity analysis is introduced in order to compute the derivatives of the objective function. And an adjoint variable method is used to save the computational efforts for sensitivity coefficients.

• Bulletin of the Korean Chemical Society
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• v.30 no.6
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• pp.1309-1312
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• 2009

Surface potential and growth processes of hexadecanethiol (HDT) self-assembled monolayers (SAMs) on Au(111) surfaces were examined by Kelvin probe method and scanning tunneling microscopy. It was found that surface potential strongly depends on surface structure of HDT SAMs. The surface potential shift for the striped phase of HDT SAMs chemisorbed on Au(111) surface was +0.45 eV, which was nearly the same as that of the flat-lying hexadecane layer physisorbed on Au(111) surface. This result indicates that the interfacial dipole layer induced by adsorption of alkyl chains is a main contributor to the surface potential change. In the densely-packed HDT monolayer, further change of the surface potential was observed, suggesting that the dipole moment of the alkanethiol molecules is an origin of the surface potential change. These results indicate that the work function of a metal electrode can be modified by controlling the molecular orientation of an adsorbed molecule.

• Honam Mathematical Journal
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• v.33 no.3
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• pp.407-418
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• 2011

There are two kinds of closing method for a given braid ${\beta}{\in}B_{2n}$, a braid closure $\hat{\beta}$ and a plat closure $\bar{\beta}$. In the article, we find a relation between the Conway potential function ${\nabla}_{\hat{\beta}}$ of braid closure $\hat{\beta}$ and ${\nabla}_{\hat{\beta}}$ of plat closure $\bar{\beta}$.