• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.10
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• pp.946-949
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• 2007

This paper discusses the lateral vibration of a beam with boundary condition of one end fixed and the other end free. The uniform beam has a solution by summation of some simple exponential functions. But if its shape is not uniform, its solution could be by Bessel's function or mathematical solution could not exist. Even if the solution of Bessel's function exists, as Bessel function is a series function, we must get the solution by numerical method. Author had proposed the solution of the matrix method by Ritz's method and a new mode shape function, and had earned the good results for a wedge beam. Hereby a vibration analysis for the tapered beam with circle cross section was executed, and so good results were showed.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.15 no.5
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• pp.499-508
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• 2004

An efficient method of moments(MoM), which can lead to the analytical evaluation of the matrix elements, is proposed to analyze microstrip structures. The present method is formulated in conjunction with use of a new closed-form spatial-domain Green's functions which are derived by use of the integral formula for semi-infinite integrals of Bessel functions. It is observed that the computational efficiency such as the amount of calculation and computation speed has been improved due to the present MoM scheme by a factor of about 4 in comparison with the previous method. To validate the proposed method, several numerical examples are presented.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.24 no.2
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• pp.84-88
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• 2012

A numerical skill for effective treatment of inclined boundaries in a finite element method is introduced. A finite element method has been frequently used to simulate hydraulic phenomena in a coastal zone since it can be applied to irregular and complex geometry. In case elliptic partial equations are governing equations for a finite element model, however, there is a difficulty in treating boundary conditions properly for cases in which boundaries are vertically inclined. In this study, a method to treat such inclined boundaries using Bessel functions for a finite element method is introduced and compared with analytical solutions.

• Proceedings of the IEEK Conference
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• 1999.06a
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• pp.323-326
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• 1999

This paper describes a point matching method that is based on an expansion of the electromagnetic field in terms of a series of Bessel and modified Bessel functions multiplied by trigonometric functions. In this method, the electric and magnetic fields inside the waveguide core are matched to those outside the core at matching points on the boundary to yield matrix equations. As an example applying this method, the paper presents the results of the computation in the form of curves of the propagation constants in a semicircular optical waveguide, be formed by annealing for reduced insertion(radiation) loss when connected to optical fiber. The propagation curves are presented in a form of refractive index independent. Also, it presents relative energy distributions between inside the core and outside the core of various modes and presents field distributions.

• Structural Engineering and Mechanics
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• v.27 no.6
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• pp.773-776
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• 2007

• Proceedings of the IEEK Conference
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• 2002.07a
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• pp.9-11
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• 2002

We improve the free-space optical interconnection efficiency by using circular aperture computer-generated hologram (CGH). In free-space optical interconnection system using CGH, the single CGH is composed of sub-CGHs, which can change the direction of input beams to desired output positions, by Fourier transform. Each sub-CGH is rectangular shape, so the input beams through each sub-CGH are transformed to sinc functions in output plane. The side lobes of each sinc function are superimposed in output plane and they result in detection error in output plane, so the detection efficiency is low. We use the circular shaped sub-CGHs in order to reduce the side lobe value in output plane instead of rectangular shaped sub-CGHs. The each input beam is transformed to first-order Bessel functions through circular shaped sub-CGHs in output plane. The side lobes of first-order Bessel functions us low values compared with side lobes of sinc function, so we can improve the detection efficiency in output plane. We use binary phase modulated CGH, and confirm this improvement results by simulation.

• Advances in materials Research
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• v.9 no.1
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• pp.15-32
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• 2020

In this article, an analytical solution is presented for the steady-state axisymmetric thermal stress distributions in a composite hollow cylinder. The cylinder is composed of two isotropic and anisotropic materials which is subjected to the thermal boundary conditions of convective as well as radiative heating and cooling on the inner and outer surfaces, respectively. The solution of the temperature is obtained by means of Bessel functions and the thermal stresses are developed using Potential functions of displacement. Numerical results are derived for a cylinder which is similar to a gas turbine combustor and showed that the maximum temperature and thermal stresses (radial, hoop, axial) occurred in the middle point of cylinder and the values of thermal stresses in anisotropic cylinder are more than the isotropic cylinder. It is worthy to note that the values of the thermal conditions which estimated in this research, not to be presented in any other papers but these values are very accurate in calculation.

• Honam Mathematical Journal
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• v.34 no.4
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• pp.473-482
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• 2012

While investigating the Lauricella's list of 14 complete second-order hypergeometric series in three variables, Srivastava noticed the existence of three additional complete triple hypergeo-metric series of the second order, which were denoted by $H_A$, $H_B$ and $H_C$. Each of these three triple hypergeometric functions $H_A$, $H_B$ and $H_C$ has been investigated extensively in many different ways including, for example, in the problem of finding their integral representations of one kind or the other. Here, in this paper, we aim at presenting further integral representations for the Srivatava's triple hypergeometric function $H_C$.

• Honam Mathematical Journal
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• v.34 no.1
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• pp.113-124
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• 2012

While investigating the Lauricella's list of 14 complete second-order hypergeometric series in three variables, Srivastava noticed the existence of three additional complete triple hypergeometric series of the second order, which were denoted by $H_A$, $H_B$ and $H_C$. Each of these three triple hypergeometric functions $H_A$, $H_B$ and $H_C$ has been investigated extensively in many different ways including, for example, in the problem of finding their integral representations of one kind or the other. Here, in this paper, we aim at presenting further integral representations for the Srivatava's triple hypergeometric function $H_A$.

• The Pure and Applied Mathematics
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• v.19 no.2
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• pp.137-145
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• 2012

While investigating the Lauricella's list of 14 complete second-order hypergeometric series in three variables, Srivastava noticed the existence of three additional complete triple hypergeometric series of the second order, which were denoted by $H_A$, $H_B$ and $H_C$. Each of these three triple hypergeometric functions $H_A$, $H_B$ and $H_C$ has been investigated extensively in many different ways including, for example, in the problem of finding their integral representations of one kind or the other. Here, in this paper, we aim at presenting further integral representations for the Srivatava's triple hypergeometric function $H_B$.