• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.11 no.5
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• pp.101-107
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• 2001

This paper deals with the free vibrations of horizontally curved beams with mu1tiple elastic springs. Taking into account the effects of rotatory Inertia and shear deformation. differential equations governing the free vibrations of such beams are derived, In which each e1astic spring is modeled as a discrete Winkler foundation with very short longitudinal length. Differential equations are solved numerically to calculate natural frequencies and mode shapes. In numerical examples, the circular, Parabolic. sinusoidal and elliptic curved beams are considered. The parametric studies are conducted and the lowest four frequency parameters are reported In tables and figures as the non-dimensional forms. Also the typical mode shapes are presented.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2002.11b
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• pp.977-981
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• 2002

The ordinary differential equations governing free vibrations of elastic horizontally curved beams are derived, in which the effect of shear deformation as well as the effects of vertical, rotatory and torsional inertias are included. Frequencies and mode shapes are computed numerically for parabolic curved beams with the hinged-hinged, hinged-clamped and clamped-clamped ends. Comparisons of natural frequencies between this study and ADINA are made to validate the theories and numerical methods developed herein. The lowest three natural frequency parameters are reported, with and without the effect of shear deformation, as functions of the three non-dimensional system parameters: the horizontal rise to span length ratio, the slenderness ratio and the stiffness parameter.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.10 no.1
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• pp.1-7
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• 1990

A method is developed for solving the elastica of cantilever beam subjected to a tip point load and uniform load. The Bernoulli-Euler differential equation of deflected beam is used. The Runge-Kutta method and the Regula Falsi method are used to perform the integration of the differential eqution and to determine the horizontal deflection, respectively. The horizontal and vertical deflections of the free end, and the free-end rotations are calculated for a range of parameters representing variations in tip point load and uniform load. All results are presented in nondimensional forms. And some typical elastic are also presented.

• Journal of the Korean Society for Precision Engineering
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• v.13 no.2
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• pp.176-184
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• 1996

The paper describes the vibration characteristics of the mechanical system consisting of a uniform Timoshenko beam with a guided mass and an elastic spring support. The free end of the beam does not rotate and the spring attatched to the guided mass is elastically restrained against translation. The guided mass is assumed to be a rigid body having a finite size, but not a mass point as it has been assumed so far. The effect of magnitudes, rotary inertia and the size of the guided mass on the vibration characteristics is fully investigated by the numerical simulation using FEM and experiment. In order to verify the eigenvalue sensitivity for considered system, comparison exact solutions with FEM is conducted, and a good agreement between two solutions is also highlighted.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.6
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• pp.384-390
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• 2015

The vibration analysis of rotating inward beams considering the pre-twisted is presented based on Euler-Bernoulli beam theory. The frequency equations, are calculated using hybrid deformation variable modeling along with the Rayleigh-Ritz assumed mode methods. In this study, resulting system of ordinary differential equations shows the effects of angular speed, and Young's modulus ratio. It is believed that the results will be a reference with which other researchers and commercial FE analysis program, ANSYS can compare their result.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.25 no.6
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• pp.420-425
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• 2015

In this paper a transfer matrix method is developed to solve for bending vibration of beam with linearly reduced width, and subsequently used to determine the exact natural frequencies for such problems. The differential equation, shear force, and bending moment are derived from Hamilton's principle, and the roots of the differential equation are computed using the power series solution of the Frobenius method. The effect of various taper ratio for bending vibration of beam with linearly reduced width is investigated in detail, and to validate the accuracy of the proposed method the results computed are compared with those given from commercial software(ANSYS).

• Annual Conference on Human and Language Technology
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• 1994.11a
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• pp.195-200
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• 1994

본 논문에서는 글자 구분선 없이 자유로이 쓰여진 필기체 한글의 인식 방안을 보인다. 즐단위의 한글 입력 영상에서 글자의 골격선을 추출하는 새로운 방법과 골격선들 간의 접촉점과 끝점을 그래프의 노드로 표현하고, 획은 그래프의 가지로 표현하는 방안을 보인다. 한글의 글자 구성 원리는 모음을 중심으로 모아쓰므로, 그래프로 표현된 즐단위의 한글에서 모음의 시작위치 및 속성을 가지는 로드로부터 한글의 모음을 가장 먼저 유도하여 인식하고, 우측 글자 및 자소끼리의 접촉을 분리하여 초성 자음 및 종성 자음을 인식하여, 좌에서 우의 방향으로 한 문자씩 인식해 나간다. 본 논문에서의 자유로이 필기된 한글의 인식 실험은 우리나라의 주소 50개를 서로 다른 25인이 필기한 영상 데이터를 사용하였고 한글 문자의 인식율은 89%이다.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.12 no.1
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• pp.82-88
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• 2002

This paper deals with the free vibrations of horizontally curved beams with transition curve. Based on the dynamic equilibrium equations of a curved beam element subjected to the stress resultants and inertia forces, the governing differential equations are derived for the out-of-plane vibration of curved beam wish variable curvature. This equations are applied to the beam having transition curve in which the third parabolic curve is chosen in this study. The differential equations are solved by the numerical procedures for calculating the natural frequencies. As the numerical results, the various parametric studies effecting on natural frequencies are investigated and its results are presented in tables and figures. Also the laboratory scaled experiments were conducted for verifying the theories developed herein.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2004.05a
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• pp.957-962
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• 2004

This paper deals with the free vibration analysis of beam-columns resting on Pasternak foundation by the Differential Quadrature Method. Based on the differential equation subjected to the boundary conditions, adopted from the open literature, which governs the free vibrations of such member, this equation is applied to the Differential Quadrature Method. For computing natural frequencies, the numerical procedures are developed by QR Algorithm, in which the Chebyshev-Gauss-Lobatto method is used for choosing the grid points. The numerical methods developed herein for computing natural frequencies are programmed in FORTRAN code, and all solutions obtained in this study are quite agreed with those in the open literature.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.21 no.6
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• pp.570-579
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• 2011

This paper deals with free vibrations of the circular curved beams with constant volume, whose cross sectional shapes are the circular solid cross-sections. Volumes of the objective beam are always held in constant regardless shape functions of the cross-sectional radius. The shape functions are chosen as the linear, parabolic and sinusoidal ones. Ordinary differential equations governing free vibrations of such beam are derived and solved numerically for determining the natural frequencies. In numerical examples, the hinged-hinged, hinged-clamped and clamped-clamped end constraints are considered. As the numerical results, relationships between frequency parameters and various beam parameters such as rise ratio, section ratio, elasticity ratio, volume ratio, slenderness ratio and taper type are reported in tables and figures.