• Title/Summary/Keyword: tip deflection

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Dynamic Characteristics of Cantilever Pipe Conveying Fluid with the Moving Masses (이동질량을 가진 유체유동 외팔 파이프극 동특성)

  • 윤한익;손인수
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.12 no.7
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    • pp.550-556
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    • 2002
  • The vibrational system of this study is consisted of a cantilever pipe conveying fluid. the moving mass upon it and an attacked tip mass. The equation of motion is derived by using Lagrange equation. The influences of the velocity and the inertia force of the moving mass and the velocities of fluid flow in the pipe haute been studied on the dynamic behavior of a cantilever pipe by numerical method. As the velocity of the moving mass increases, the deflection of cantilever pipe conveying fluid is decreased. Increasing of the velocity of fluid flow make the amplitude of cantilever pipe conveying fluid decrease. The deflection of the cantilever pipe conveying fluid is increased by moving masses. After the moving mass passed upon the cantilever pipe, the amplitude of pipe is influenced due to the deflection of pipe tilth the effect of moving mass and gravity.

Design of the monoleaflet polymer valve to minimize stress and displacement (응력 및 변위를 최소화하기 위한 단엽식 고분자 판막의 설계)

  • Han, G.J.;Kim, S.H.
    • Proceedings of the KOSOMBE Conference
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    • v.1993 no.11
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    • pp.99-103
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    • 1993
  • A monoleaflet polymer artificial heart valve which showed the remarkable improvement in pressure drop compared with other types of artificial valve was designed to decrease the deflection in vertical direction and the displacement or the valve tip in horizontal direction. Stress distribution change was studied as the location of the supporting members or the valve frame changed. And it was found that using the valve tip horizontal displacement the minimum valve thickness could be obtained in order to prevent the gap between the valve tip and the frame wall.

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Extensible Elastica Solutions on the Large Deflection of Fiber Cantilever with Circular Wavy Crimp (I) - Derivation of Models and Their Solutions-

  • Jung Jae Ho;Kang Tae Jin
    • Fibers and Polymers
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    • v.6 no.1
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    • pp.55-65
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    • 2005
  • Extensible elastica solutions of two-dimensional deflection of crimped fiber cantilever of circular wavy crimp were obtained for one end clamped boundary under concentrated, inclined and dead tip load Fiber was also regarded as a linear elastic material. Crimp was described as a combination of semicircular arcs smoothly connected with each other having con­stant curvature of all the same magnitude and alternative sign. Also the inclined load direction was taken into account. The solutions were expressed as the recursive forms of integrals in two different cases, which can also be transformed to elliptic integrals respectively. Comparing the data with inextensible ones was carried out. Consequently in the solution, the normal strain of neutral axis is expressed in terms of cross-sectional area, second moment of area and normalized load parameter. Examples of the circular cross-sectioned fiber are presented. As a result, the differences of normalized load between inexten­sible and extensible elastica solutions when the radius ratio becomes 0.1 were maximum $\Lambda$ = 0.1.

Lateral Behavior of Sin811e and Group Piles in Sand (사질토 지반에서 말뚝의 수평거동)

  • 김영수;김병탁
    • Proceedings of the Korean Geotechical Society Conference
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    • 1999.10a
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    • pp.3-44
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    • 1999
  • This paper discusses the lateral behavior of single and group piles in homogeneous and non-homogeneous(two layered) soil. In the single pile, the model tests were conducted to investigate the effects on ratio of lower layer height to embedded pile length, ratio of soil modules of upper layer to lower layer, boundary rendition of pile head and tip, embedded pile length, pile construction condition, ground condition with saturate and moisture state in Nak-Dong river sand. Also, in the group pile, the model tests were to investigate the effects on spacing-to-diameter ratio of pile, pile array, ratio of pile spacing, boundary condition of pile head and tip, eccentric load and ground condition. The maximum bending moment and deflection induced in active piles were found to be highly dependent on the relative density, pile construction condition, boundary condition of pile head and tip. Based on the results obtained, it was found that the decrease of lateral bearing capacity in saturated sand was in the range of 31% - 53% as compared with the case of dry sand. Also, in the group pile, a spacing-to-diameter of 6.0 seems to be large enough to eliminate the group effect for the case of relative density of 61.8%, and 32.8%, and then each pile in such a case behaves essentially the same as a single pile. In this study, the program is developed by using the modified Chang method which used p - y method and the exact solution of governing equation of pile and it can be used to calculate the deflection, bending moment and soil reaction with FDM in non-homogeneous soil. In comparing the modified Chang method with field test results, the predict results shows better agreement with measured results in field tests.

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Linear Analysis and Non-linear Analysis with Co-Rotational Formulation for a Cantilevered Beam under Static/Dynamic Tip Loads (정적 및 동적 하중을 받는 외팔보 거동에 관한 선형 및 CR 정식화 비선형 예측의 비교)

  • Ko, Jeong-Woo;Bin, Young-Bin;Eun, Won-Jong;Shin, Sang-Joon
    • Journal of the Computational Structural Engineering Institute of Korea
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    • v.28 no.5
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    • pp.467-475
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    • 2015
  • In this paper, the behaviour of a cantilevered beam was predicted to examine the difference between linear and non-linear static, dynamic analysis for a structure by using CR nonlinear formulation. Then, external transverse static and dynamic loads were applied at the free tip of the beam. Classical theories were used for the present linear analysis and co-rotational dynamic FEM program was used for the present nonlinear analysis. In the static analysis, effects of the load for the beam deflection were observed in both linear and nonlinear analysis. Then, normalized displacement at the tip of the beam was predicted for different frequency ratio and a significant difference was obtained in the vicinity of the resonant frequency. In addition, effects of frequency and time for the beam deflection were investigated to find the frequency delay.

Influence of Design Parameters on Dynamic Behavior and Frequencies of Cantilever ripe Conveying Fluid (유체유동을 갖는 외팔 파이프의 동특성 및 진동수에 미치는 설계인자의 영향)

  • Yoon, Han-Ik;Son, In-Soo;Park, Il-Ju
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.27 no.11
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    • pp.1815-1823
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    • 2003
  • The vibrational system of this study consists of a cantilever pipe conveying fluid, the moving masses upon it and having an attached tip mass. The equation of motion is derived by using Lagrange's equation. The influences of the velocity and the inertia force of the moving mass and the velocities of fluid flow in the pipe have been studied on the dynamic behavior and the natural frequency of a cantilever pipe by numerical method. The deflection of the cantilever pipe conveying fluid is increased due to the tip mass and rotary Inertia. After the moving mass passed upon the cantilever pipe, the amplitude of pipe is influenced by energy variation when the moving mass fall from the cantilever pipe. As the moving mass increase, the frequency of the cantilever pipe conveying fluid is increased. The rotary inertia of the tip mass influences much on the higher frequencies and vibration mode.

A FINITE ELEMENT ANALYSIS ON THE 3-UNIT FIXED PROSTHESIS SUPPORTED WITH A NATURAL TOOTH AND ANGLE VARIABLE IMPLANT (고정성 보철치료에서 골유착성 임프란트의 경사도변화에 따른 변위와 응력에 관한 유한요소적 연구)

  • Ko Hyun;Woo Yi-Hyung;Park Nam-Soo
    • The Journal of Korean Academy of Prosthodontics
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    • v.31 no.4
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    • pp.580-610
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    • 1993
  • The purpose of this study was to analyse the deflection and stress distribution at the supporting bone and it's superstructure by the alteration of angulation between implant and it's implant abutment. For this study, the free-end saddle case of mandibular first and second molar missing would be planned to restore with fixed prosthesis. So the mandibular second premolar was prepared for abutment, and the cylinder type osseointegrated implant was placed at the site of mandibular second molar for abutment. The finite element stress analysis was applied for this study. 13 two-dimensional FEM models were created, a standard model at $0^{\circ}$ and 12 models created by changing the angulation between implant and implant abutment as increasing the angulation mesially and distally with $5^{\circ}$ unittill $30^{\circ}$. The preprocessing decording, solving and postprocessing procedures were done by using FEM analysis software PATRAN and SUN-SPARC2GX. The deflections and von Mises stresses were calculated under concentrated load (load 1) and distributed load(load 2) at the reference points. The results were as follows : 1. Observing at standard model, the amount of total deflection at the distobuccal cusp-tip of pontic under concentrated load was largest of all, and that at the apex of implant was least of all, and the amount of total deflection at the buccal cusp-tip of second premolar under distributed load was largest of all, and that at the apex of implant was least of all. 2. Increasing the angulation mesially or distally, the amounts of total deflection were increased or decreased according to the reference points. But the order according to the amount of total deflection was not changed except apex of second premolar and central fossa of implant abutment under concentrated load during distal inclination. 3. Observing at standard model, the von Mises stress at the distal joint of pontic under concentrated load was largest of all, and that at the apex of implant was least of all. The von Mises stress at the distal margin of second premolar under distributed load was largest of all, and that at the apex of Implant was least of ail. 4. Increasing the angulation of implant mesially, the von Mises stresses at the mesial crest of implant were increased under concentrated load and distributed load, but those were increased remarkably under distributed load and so that at $30^{\circ}$ mesial inclination was largest of all. 5. Increasing the angulation of implant distally, the von Mises stresses at the distal crest of implant were increased remarkably under concentrated load and distributed load, and so those at $30^{\circ}$ distal inclination were largest of all.

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Fuzzy -Logic Controller for Flexible-Link Manipulators (유연 링크 로봇의 제어)

  • 강재용;박종현
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 1995.10a
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    • pp.342-345
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    • 1995
  • This paper describes the design process and the experimental results of a fuzzy logic controller to control the tip position of a fixible-link manipulator, directly driven by a AC motor, with a large payload. The joint angle fuzzy logic controller is designed without a costly nonlinear system analysis of the flexible manipulator and the AC motor drive system. The state variables for the fuzzy logic controller are joint angle, joint velocity, link deflection, and link deflection velocity. The simulation and experimental results show that the joint position control is not satisfactory when the controller is designed under the assumption of no link flexibility and that stable joint position control and link vibration suppression can be cahieved with the fuzzy logic controller suggested in this paper.

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수직방향 집중하중 상태의 외팔보 거동에 대한 선형 및 비선형적 해석 비교

  • Go, Jeong-U;Bin, Yeong-Bin
    • Proceeding of EDISON Challenge
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    • 2015.03a
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    • pp.239-245
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    • 2015
  • In this paper, to examine the difference between the linear and non-linear static, dynamic analysis for a structure, a cantilevered beam was used. Then, an external transverse static and dynamic loads were applied at the free end of the beam. Classical theories were used for the linear analysis and the EDISON CSD solver, co-rotational dynamic FEM program, was used for nonlinear analysis. In the static analysis, effects of the load for the beam deflection were observed in the linear and nonlinear analysis. Then, normalized displacement of tip of the beam was predicted for different frequency ration and a significant difference was obtained in the vicinity of the resonant frequency. In addition, effects of frequency and time for the beam deflection were investigated to find the frequency delay.

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On the large plastic deformation of tubular beams under impact loading

  • Wang, B.
    • Structural Engineering and Mechanics
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    • v.3 no.5
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    • pp.463-474
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    • 1995
  • When a tubular cantilever beam is loaded by a dynamic force applied transversely at its tip, the strain hardening of the material tends to increase the load carrying capacity and local buckling and cross-sectional overlization occurring in the tube section tends to reduce the moment carrying capacity and results in structural softening. A theoretical model is presented in this paper to analyze the deformation of a tubular beam in a dynamic response mode. Based on a large deflection analysis, the hardening/softening M-${\kappa}$ relationship is introduced. The main interest is on the curvature development history and the deformed configuration of the beam.