• 제목/요약/키워드: 동적 질량

검색결과 320건 처리시간 0.029초

Pasternak지반에 지지된 집중질량을 갖는 보강된 변단면 후판의 동적안정해석 (Dynamic Stability Analysis of Stiffened Tapered Thick Plate with Concentrated Mass on Pasternak Foundations)

  • 이용수;김일중
    • 한국소음진동공학회논문집
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    • 제19권12호
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    • pp.1296-1305
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    • 2009
  • This paper has the object of investigating dynamic stability of stiffened tapered thick plate with concentrated mass on Pasternak foundation by means of finite element method and providing kinematic design data for mat of building structures. Finite element analysis of stiffened tapered thick plate is done by use of rectangular finite element with 8-nodes. In order to analysis plate which is supported on Pasternak foundation, the Winkler foundation parameter is varied with 10, 100, 1000 and the shear foundation parameter is 5, 10, concentrated mass is $0.25m_c$, $1.0m_c$, tapered ratio is 0.25, 0.5. The ratio of In-plane force to critical load is applied as $0.4\sigma_{cr},\;0.6\sigma_{cr},\;0.8\sigma_{cr}$ respectively. This paper analyzed varying tapered ratio.

유동유체에 의한 파이프의 동적안정성에 미치는 외부감쇠와 말단질량의 영향 (Effect of External Damping and Tip Mass on Dynamic Stability of Pipes Conveying Fluid)

  • 김효준;류봉조;정승호
    • 한국소음진동공학회논문집
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    • 제19권6호
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    • pp.569-574
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    • 2009
  • The paper presents the influences of the external damping and the tip mass on dynamic stability of a vertical cantilevered pipe conveying fluid. In general, real pipe systems may have some valves and attached mechanical parts, which can be regarded as attached lumped masses and support-dampers. The support-dampers can be assumed as viscous dampers. The equations of motion are derived by energy expressions using extended Hamilton's principle, and some numerical results using Galerkin's method are presented. Critical flow velocities and stability maps of the pipe with external dampers and tip mass are obtained for various tip mass ratios, external damping coefficients and positions of the viscous dampers.

동적 저울의 진동응답 측정에 의한 질량 추정 알고리즘 (Mass-estimation Algorithm by Vibration Response Measurement of Dynamic Balance)

  • 김병삼
    • 한국음향학회지
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    • 제19권5호
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    • pp.71-78
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    • 2000
  • Quickness and precision are the two most important requirements for an industrial scale used in production lines. In this paper, a new approach, "Mass-estimation algorithm by vibration-response measurement of dynamic balance", is presented to improve some of drawbacks in conventional scales. The system, consisted of velocity and displacement sensors, spring scale, analog-digital converter and microcomputer, is based on full utilization of dynamic mass measurement of velocity and displacement via microcomputer-assisted real time monitoring. The resulting system, when combined with appropriate mass estimation algorithm software, has shown its effectiveness in terms of two desirable characteristics required.

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이동질량에 의한 탄성 지지된 보의 동적응답 실험 (Experiments on Dynamic Response of an Elastically Restrained Beam under a Moving Mass)

  • 이종원;류봉조;이규섭;김효준
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2003년도 춘계학술대회논문집
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    • pp.275-280
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    • 2003
  • This paper discusses on the dynamic responsed of an elastically restrained beam under a moving mass of constant velocity. Governing equations of motion taking into account of all inertia effects of the moving mass were derived by Galerkin's mode summation method, and Runge-Kutta integration method was applied to solve the differential equations. Numerical solutions for dynamic deflections of beams were obtained for the changes of the various parameters (spring stiffness, spring position, mass ratios and velocity ratios of the moving mass). In order to verify the numerical predictions for the dynamic response of the beam, experiments were conducted. Numerical solutions for the dynamic responses of the test beam have a good agreement with experimental ones.

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복수 부가질량을 갖고 유동유체에 의한 수직외팔 파이프의 동적안정성에 관한 실험적 검증 (Experimental Verification on Dynamic Stability of a Vertical Cantilevered Pipe with Attached Masses Conveying Fluid)

  • 김삼일;정승호;류봉조
    • 한국소음진동공학회논문집
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    • 제11권6호
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    • pp.208-215
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    • 2001
  • The paper presents both theoretical and experimental study fur dynamic instabilities of a vortical cantilevered pipe with two attached lumped masses conveying fluid. The two attached lumped masses can be considered as valves or some mechanical paras in real pipe systems. Eigenvalue behaviors depending on the flow velocity are investigated for the change of Positions and magnitudes of an attached lumped mass and a tip mass. In order to verify appropriate of numerical solutions, experiments were accomplished. Theoretical predictions have a good agreement with experimental ones.

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유동유체에 의한 파이프의 동적안정성에 미치는 외부감쇠와 말단질량의 영향 (Effect of External Damping and Tip Mass on Dynamic Stability of Pipes Conveying Fluid)

  • 류봉조;정승호;신광복;한현희
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2005년도 추계학술대회논문집
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    • pp.465-468
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    • 2005
  • The paper deals with the influences of external damping and tip mass on dynamic stability of a vertical cantilevered pipe conveying fluid. In general, real pipe systems may have some valves and attached parts, which can be regarded as attached lumped masses and support-dampers. The support-dampers can be assumed as viscous dampers. The equations of motion are derived by energy expressions using extended Hamilton's principle, and some numerical results using Galerkin's method are presented. Critical flow velocities and stability maps of the pipe with external dampers and tip mass are obtained for various tip mass ratios, external damping coefficients and positions of the viscous dampers.

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가속을 갖는 이동질량에 의한 외팔보의 동적응답에 관한 실험적 검증 (Experimental Verification on Dynamic Responses of a Cantilevered Beam under a Moving Mass with Accelerations)

  • 김희중;류봉조;김효준;윤충섭
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2004년도 추계학술대회논문집
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    • pp.307-310
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    • 2004
  • The paper presents the numerical and experimental results for the dynamic response vibration of a cantilevered beam subjected to a moving mass with variable speeds. Governing equations of motion under a moving mass were derived by Galerkin's mode summation method taking into account the effects of all forces due to moving mass, and the numerical results were calculated by Runge-Kutta integration method. The effects of the speed, acceleration and the magnitude of the moving mass on the response of the beam are fully investigated. In order to verify numerical results, some experiments were conducted, and the numerical results have a little difference with the experimental ones.

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동적 상태의 선박 조향각 및 실시간 질량 추정 시스템 (Caculating Ship Rudder Angle and Real-Time Mass Estimator Under Dynamic State)

  • 명진혁
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2022년도 춘계학술대회
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    • pp.31-32
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    • 2022
  • 초기의 선박들은 선회시 킥현상 등을 설명하고 대응하는 선박의 전복예방을 위한 정확한 방정식이 제공되지 못했다. 육상에서는 차량의 정상상태 선회방정식을 이용한 전복예방 기술이 많이 개발되었고 이는 해상에서의 기존의 방법들 보다 더 좋은 성능을 보였다. 이 논문에서는 더 정확한 선박의 선회시 전복방지를 위해 애커만 기하학 모델 기반 선회방정식을 이용하여 선박선회시 복원을 하는 방법을 제안하여 선박안전관리 방안을 향상시킨다.

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수직축 선형 영구자석 동기전동기의 질량 추정 (Mass Estimation of a Permanent Magnet Linear Synchronous Motor Applied at the Vertical Axis)

  • 이진우;지준근;목형수
    • 전력전자학회논문지
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    • 제13권6호
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    • pp.487-491
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    • 2008
  • 선형 서보 응용분야에 사용되는 속도제어기를 정밀하게 조정하기 위해서는 부하를 포함한 가동부 전체의 정밀한 질량이 필요하다. 본 논문에서는 수직축 선형 영구자석 동기전동기의 가동부 질량을 추정하기 위한 방법으로 축차 최소자승 추정 알고리즘을 적용한 질량 추정방법을 제안한다. 먼저 수직축 선형 영구자석 동기 전동기의 기계적인 동적 시스템에 대한 DARMA(deterministic autoregressive moving average)모델을 유도하고, 유도된 DARMA모델에 축차 최소자승 추정 방법을 적용한 질량 추정방법을 제안하며, Matlab/Simulink를 이용한 시뮬레이션 및 실험 결과를 제시하여 제안한 방법으로 수직축 질량을 무부하 및 부하 시 모두 정밀하게 추정할 수 있음을 보였다.

질량비정형을 갖는 강 모멘트 저항 골조의 지진에너지 반응 (Seismic Energy Response of Steel Moment Resisting Frames with Mass Irregularity)

  • Choi, Byong-Jeong;Song, In-Hawn
    • 한국지진공학회:학술대회논문집
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    • 한국지진공학회 2003년도 추계 학술발표회논문집
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    • pp.213-220
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    • 2003
  • 고층의 강 모멘트저항골조에 대한 지진 반응을 살펴보기 위해서 동적해석을 실시하였다. 구조물은 세가지의 다른 설계절차로 의도적으로 설계하였고 그 세가지의 개념은 강도 지배설계, 강기둥-약보 지배설계, 횡변위 지배설계이다. 그렇게 설계한 구조물이 각각 질량비정형이 존재하도록 하여 힁변위, 소성힌지, 이력에너지 입력 및 요구응력에 대해서 토론하였다. 미래에 설계에의 응용을 위해서 최대 지반가속도로 표현한 두 등급의 지진 하중을 이용해서 이력에너지 입력요구 곡선을 제시하였다.

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