• 제목/요약/키워드: moving

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Airside 이동체 안전관리 기술 개발 (Development of Safety Management System for Moving Vehicles in Airside)

  • 한재현;김요식
    • 한국항공운항학회지
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    • 제16권4호
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    • pp.75-82
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    • 2008
  • As the number of passengers and the amount of cargo is getting increased, the traffic of aircraft and moving vehicle at an airport is getting busy. Especially, due to the heavy traffic of moving vehicles in the area of airside, the safety management of them is getting important. The study has been performed for suggesting improved methods in order to reduce safety accidents between aircraft and moving vehicles by introducing a safety management system for moving vehicles in airside of an airport. In order to improve the level of safety with the efficient management of moving vehicles in airside, the analysis of the domestic and international trends of the related technology and regulations has been performed. As a result, the conceptual design of safety management system has been suggested by utilizing the location information technology and four layers (hardware, network, middleware and application) approaches of safety management system.

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여러 스팬을 갖는 티모센코 보 구조물의 이동하중에 의한 진동 해석 (Vibration Analysis of Multi-Span Timoshenko Beams Due to Moving Loads)

  • 홍성욱;김종욱
    • 대한기계학회논문집A
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    • 제23권11호
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    • pp.2058-2066
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    • 1999
  • The present paper proposes a new dynamic analysis method for multi-span Timoshenko beam structures supported by joints with damping subject to moving loads. An exact dynamic element matrix method is adopted to model Timoshenko beam structures. A generalized modal analysis method is applied to derive response formulae for beam structures subject to moving loads. The proposed method offers an exact and closed form solution. Two numerical examples are provided for validating and illustrating the proposed method. In the first numerical example, a single span beam with multiple moving loads is considered. A dynamic analysis on a multi-span beam under a moving load is considered as the second example, in which the flexibility and damping of supporting joints are taken into account. The numerical study proves that the proposed method is useful for the vibration analysis of multi-span beam-hype structures by moving loads.

축방향으로 이송되는 유체유동 단순지지 파이프의 안정성 해석 (Stability Analysis of Axially Moving Simply Supported Pipe Conveying Fluid)

  • 손인수;허관도;이상필;조정래
    • 한국소음진동공학회논문집
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    • 제22권5호
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    • pp.407-412
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    • 2012
  • The dynamic instability and natural frequency of an axially moving pipe conveying fluid are investigated. Thus, the effects of fluid velocity and moving speed on the stability of the system are studied. The governing equation of motion of the moving pipe conveying fluid is derived from the extended Hamilton's principle. The eigenvalues are investigated for the pipe system via the Galerkin method under the simple support boundary. Numerical examples show the effects of the fluid velocity and moving speed on the stability of system. Moreover, the lowest critical moving speeds for the simply supported ends have been presented.

영구자석에 의한 반발형 자기부상 테이블의 안정성 해석 (Stability Analyses of Magnetic Levitation Tables Using Repulsions of Permanent Magnets)

  • 최기봉;조영근;신시타다히코;시모코베아키라
    • 한국정밀공학회지
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    • 제19권7호
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    • pp.36-42
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    • 2002
  • This paper presents two actuators for levitation using repulsions of permanent magnet and two magnetic levitation tables using the actuators. Here, one actuator for levitation consists of one fixed magnet and one moving magnet, and the other actuator consists of two fixed magnets and one moving magnet. The moving part of the magnetic levitation table contains the moving magnets. repulsive forces caused by the permanent magnets are linearized, and then the equation of motion of the moving part of the table is derived. Using the equation of motion, stability conditions of the moving part are deduced. The stability conditions are analyzed for positional relations of the moving magnets and the minimum number of active control required for stable system. As a result, in the each case of magnetic levitation tables, the requirements for stabilization are expressed by the positional relations and the number of the active controls.

Motion Analysis of a Translating Flexible Beam Carrying a Moving Mass

  • Park, Sangdeok;Youngil Youm
    • International Journal of Precision Engineering and Manufacturing
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    • 제2권4호
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    • pp.30-39
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    • 2001
  • This paper investigates vibrational motion of a flexible beam fixed on a moving cart and carrying a moving mass. The equations of motion of the beam-mass-cart system are analysed through the unconstrained modal analysis. The exact normal mode solution used in modal analysis correspond to the eigenfrequencies for each position of the moving mass and to the ratios of the weight of the beam-mass-car system. Time solutions of normal modes are also transformed properly according to the position of the moving mass. Numerical simulations are carried out to obtain open-loop responses of the system in tracking pre-designed paths of the moving mass. The simulation results show that the model predicts the dynamic behavior of the beam-mass-cart system well. Experiments are carried out to show the validity of the proposed analytical method.

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이동형 로봇의 기구학적 분류에 따른 기술동향 (Technical Trend of Mobile Robot According to Kinematic Classification)

  • 정찬세;박경택;양순용
    • 제어로봇시스템학회논문지
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    • 제19권11호
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    • pp.1043-1047
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    • 2013
  • Smart mobile robot is a kind of Intelligent Robot. It means that operates manipulate autonomously and recognize the external environment. Smart mobile robot moving mechanism has many type and the type depend on the robot shape or purpose. Recently, research on the moving mechanism has been actively in many area. The moving mechanism divided to wheel type, crawler type, walking type, other type and the moving type choose by the kind of robot or the purpose robot. In this paper, describe the kind of moving mechanism on the smart mobile robot and the technical trend of moving mechanism of smart mobile robot.

비디오에서 객체의 시공간적 연속성과 움직임을 이용한 동적 객체추출에 관한 연구 (A Study on the Extraction of the dynamic objects using temporal continuity and motion in the Video)

  • 박창민
    • 디지털산업정보학회논문지
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    • 제12권4호
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    • pp.115-121
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    • 2016
  • Recently, it has become an important problem to extract semantic objects from videos, which are useful for improving the performance of video compression and video retrieval. In this thesis, an automatic extraction method of moving objects of interest in video is suggested. We define that an moving object of interest should be relatively large in a frame image and should occur frequently in a scene. The moving object of interest should have different motion from camera motion. Moving object of interest are determined through spatial continuity by the AMOS method and moving histogram. Through experiments with diverse scenes, we found that the proposed method extracted almost all of the objects of interest selected by the user but its precision was 69% because of over-extraction.

이동질량과 압축력을 받는 티모센코 회전축의 무차원 변수 연구 (Nondimensional Parametric Study of a Timoshenko Rotating Shaft Subject to Moving Mass and Compressive Axial Forces)

  • 박용석;홍성철
    • 한국소음진동공학회논문집
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    • 제17권12호
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    • pp.1201-1207
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    • 2007
  • The Timoshenko beam theories are used to model the rotating shaft. The nondimensional equations of motion for the rotating shaft subjected to moving mass and compressive axial forces are derived by using Hamilton's principle. Influence of system parameters such as the speed ratio. the mass ratio and the Rayleigh coefficient is discussed on the response of the moving system. The effects of compressive axial forces are also included in the analysis. The results are presented and compared with the available solutions of a rotating shaft subject to a moving mass and a moving load.

연속이동 스프링-질량계가 등분포종동력을 받는 단순보의 동특성에 미치는 영향 (Influence of Successive Two Moving Spring-Mass Systems on Dynamic Behavior of a Simple Beam Subjected to Uniformly Distributed Follower Forces)

  • 유진석;윤한익;강혁준
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2002년도 춘계학술대회논문집
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    • pp.82-88
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    • 2002
  • A simple beam subjected to a uniformly distributed tangential follower force and the successive two moving spring-mass systems upon it constitute this vibration system. The influences of the velocities of the moving spring-mass system, the distance between the successive two moving spring-mass systems and the uniformly distributed tangential follower force have been studied on the dynamic behavior of a simple beam by numerical method. The uniformly distributed tangential follower force is considered within its critical value of a simple beam without the successive two moving spring-mass systems, and three kinds of constant velocities and constant distance of the successive two moving spring-mass systems are also chosen. Their coupling effects on the transverse vibration of the simple beam are inspected too.

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격자변환기법을 이용한 이동물체 주위의 유동해석 (A Numerical Analysis on Flows Around a Moving Body Using a Mesh Transformation Method)

  • 김태균;허남건
    • 대한기계학회논문집B
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    • 제25권4호
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    • pp.593-599
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    • 2001
  • A flow analysis is performed in the present study for the moving body problem by proposing a mesh transformation method for the movement of the body in the fluid medium. Unlike other moving mesh techniques, a mesh itself is not moving but changes its property as time marches in a mesh transformation method. The flow field results are compared with those by other moving mesh technique, and showed good agreements. The movement of a floatable body in the flow field caused by the moving body is also studied in the present study by using a mesh transformation technique and a fluid/structure interaction method.