• Title/Summary/Keyword: 자유보

Search Result 935, Processing Time 0.024 seconds

Numerical Analysis of Large Deflections of Cantilever Beams (캔틸레버 보의 과대처짐 해석)

  • Lee, Byoung Koo
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.10 no.1
    • /
    • pp.1-7
    • /
    • 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.

  • PDF

Free Vibration of Beams with a Guided Mass and an Elastic Spring Support (안내질량을 갖는 탄성지지된 보의 자유진동)

  • Ryu, Bong-Jo;Lee, Gyu-Seop;Lee, Jong-Won
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.13 no.2
    • /
    • pp.176-184
    • /
    • 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.

  • PDF

Vibration Analysis of Rotating Pre-twisted Inward Beams with a Concentrated Mass (집중질량과 초기 비틀림을 갖는 회전중심방향 자유단 외팔보의 진동해석)

  • Lee, Gun Ho;Yoo, Hong Hee
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.25 no.6
    • /
    • pp.384-390
    • /
    • 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.

Exact Solutions for Bending Vibration of Beam with Linearly Reduced width Along Its Length (길이를 따라 선형적으로 감소된 폭을 가지는 보의 굽힘 진동에 대한 정확해)

  • Lee, Jung Woo;Kim, Jung Ho;Lee, Jung Youn
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.25 no.6
    • /
    • pp.420-425
    • /
    • 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).

Recognition of Handprinted Hangul Line using Vowel Pre-Recognition Method (모음 우선 인식에 의한 즐단위 필기체 한글의 인식)

  • Ham, Kyung-Soo
    • Annual Conference on Human and Language Technology
    • /
    • 1994.11a
    • /
    • pp.195-200
    • /
    • 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.

  • PDF

Free Vibrations of Horizontally Curved Beams with Transient Curve (완화곡선을 갖는 수평 곡선보의 자유진동)

  • 이병구;진태기;이태은
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.12 no.1
    • /
    • pp.82-88
    • /
    • 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.

Free Vibration Analysis of Beam-columns Resting on Pasternak Foundation by Differential Quadrature Method (미분구적법에 의한 Pasternak지반 위에 놓인 보-기둥의 자유진동 해석)

  • 이태은;이병구;강희종
    • Proceedings of the Korean Society for Noise and Vibration Engineering Conference
    • /
    • 2004.05a
    • /
    • pp.957-962
    • /
    • 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.

  • PDF

Free Vibrations of Circular Curved Beams with Constant Volume (일정체적 원호형 곡선보의 자유진동)

  • Lee, Byoung-Koo;Lee, Tae-Eun;Choi, Jong-Min;Park, Chang-Eun
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.21 no.6
    • /
    • pp.570-579
    • /
    • 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.

Free Vibration Analysis of Parabolic Hollowed Beam-columns with Constant Volume (일정체적을 갖는 포물선형 중공 보-기둥의 자유진동 해석)

  • Lee, Tae-Eun;Lee, Byoung-Koo
    • Transactions of the Korean Society for Noise and Vibration Engineering
    • /
    • v.21 no.4
    • /
    • pp.384-391
    • /
    • 2011
  • This paper deals with free vibrations of the parabolic hollowed beam-columns with constant volume. The cross sections of beam-column taper are the hollowed regular polygons whose depths are varied with the parabolic functional fashion. Volumes of the objective beam-columns are always held constant regardless given geometrical conditions. Ordinary differential equation governing free vibrations of such beam-columns are derived and solved numerically for determining the natural frequencies. In the numerical examples, hinged-hinged, hinged-clamped and clamped-clamped end constraints are considered. As the numerical results, the relationships between non-dimensional frequency parameters and various beam-column parameters such as end constraints, side number, section ratio, thickness ratio and axial load are reported in tables and figures.

Structural Analysis of Frames with Shear Walls (전단벽(剪斷壁)을 가진 프레임의 구조해석(構造解析)에 관한 연구(研究))

  • Lee, Dong Guen;Kang, Suk Bong
    • KSCE Journal of Civil and Environmental Engineering Research
    • /
    • v.6 no.2
    • /
    • pp.77-83
    • /
    • 1986
  • In this paper, an accurate model for structural analysis of frames with shear walls is introduced. Static and dynamic analysis of two example structures has been performed using the computer program SWAN which employes the newly developed 12 degrees of freedom plane stress element and the results are compared to those obtained using SAP IV. The 12 degrees of freedom element resulted in improved shear stress distribution in wall elements and bending moment in beam elements.

  • PDF