• 제목/요약/키워드: moving

검색결과 12,750건 처리시간 0.032초

WHEEL SLIP CONTROL WITH MOVING SLIDING SURFACE FOR TRACTION CONTROL SYSTEM

  • Chun, K.;Sunwoo, M.
    • International Journal of Automotive Technology
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    • 제5권2호
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    • pp.123-133
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    • 2004
  • This paper describes a robust and fast wheel slip tracking control using a moving sliding surface technique. A traction control system (TCS) is the active safety system used to prevent the wheel slipping and thus improve acceleration performance, stability and steerability on slippery roads through the engine torque and/or brake torque control. This paper presents a wheel slip control for TCS through the engine torque control. The proposed controller can track a reference input wheel slip in a predetermined time. The design strategy investigated is based on a moving sliding surface that only contains the error between the reference input wheel slip and the actual wheel slip. The used moving sliding mode was originally designed to ensure that the states remain on a sliding surface, thereby achieving robustness and eliminating chattering. The improved robustness in driving is important due to changes, such as from dry road to wet road or vice versa which always happen in working conditions. Simulations are performed to demonstrate the effectiveness of the proposed moving sliding mode controller.

티모센코 회전축을 따라 움직이는 질량의 진동해석 (Vibration Analysis of a Moving Mass Travelling on the Timoshenko Rotating Shaft)

  • 박용석
    • 한국산학기술학회논문지
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    • 제9권4호
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    • pp.859-864
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    • 2008
  • 티모센포 회전축을 따라 이동하는 이동질량과의 동적상호작용에 관한 연구가 수행되었다. 이동질량의 속력이 티모센코축의 회전속도와 연계된 구속조건식을 도출하였다. 티모센코의 보 이론를 활용하여 시스템의 무차원방정식이 유도되었다. 이동질량의 속력을 포함하는 티모센코 축의 회전속도, 레일리히 계수, 축방향 압축력 등 다양한 무차원 변수들의 영향에 따른 회전축의 처짐과 주파수응답에 대한 해석이 수행되어졌다.

Managing and Querying Moving Objects in Networks

  • Kim Jae-Chul;Heo Tae-Wook;Lee Jai-Ho;Kim Kwang-Soo
    • 대한원격탐사학회:학술대회논문집
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    • 대한원격탐사학회 2004년도 Proceedings of ISRS 2004
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    • pp.367-370
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    • 2004
  • We model a moving object as a sizable physical entity equipped with GPS, wireless communication capability, and a computer such as a PDA and mobile phone. Furthermore, we have observed that a real trajectory of a moving object is the result of interactions among moving objects in the system yielding Multi-points instead of a line segment. In this paper, the new types and operations are integrated seamlessly into the moving object framework to achieve a relatively simple, consistent and powerful overall model and query language for constrained and unconstrained movement.

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Dynamic stiffness matrix method for axially moving micro-beam

  • Movahedian, Bashir
    • Interaction and multiscale mechanics
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    • 제5권4호
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    • pp.385-397
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    • 2012
  • In this paper the dynamic stiffness matrix method was used for the free vibration analysis of axially moving micro beam with constant velocity. The extended Hamilton's principle was employed to derive the governing differential equation of the problem using the modified couple stress theory. The dynamic stiffness matrix of the moving micro beam was evaluated using appropriate expressions of the shear force and bending moment according to the Euler-Bernoulli beam theory. The effects of the beam size and axial velocity on the dynamic characteristic of the moving beam were investigated. The natural frequencies and critical velocity of the axially moving micro beam were also computed for two different end conditions.

관내 전파되는 파동에 대한 파이프의 구조적 반응에 대한 모델링 (Modeling of the Structural Response of Pipes to Internal Blast Loading)

  • 김대현;여재익
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2008년도 제30회 춘계학술대회논문집
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    • pp.9-13
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    • 2008
  • 충격파와 같은 moving load가 특별한 속도로 관 안을 전파한다. 이 관 안을 전파하는 moving load 속도는 flexural wave의 활성화의 정도와 큰 변형을 일으키는 공진이 발생할 가능성을 결정한다. 본 연구에서, 우리는 moving load가 관안을 통과하고 있을 때의 변위의 특별해와 공진현상이 일어날 조건을 보일 것이다. 또한 이 이론적 결과를 hydrocode를 이용하여 얻은 수치해석 결과와 비교하여 정당성을 보일 것이다. 이와 같은 결과를 바탕으로 본 연구는 원자력 발전소나 탄화수소 계열의 연료를 사용하는 산업분야에서 공진현상에 의한 대형 사고를 예방하는 목적을 가지고 있다.

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Dynamic response of a beam on multiple supports with a moving mass

  • Lee, H.P.
    • Structural Engineering and Mechanics
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    • 제4권3호
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    • pp.303-312
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    • 1996
  • The dynamic behavior of an Euler beam with multiple point constraints traversed by a moving concentrated mass, a "moving-force moving-mass" problem, is analyzed and compared with the corresponding simplified "moving-force" problem. The equation of motion in matrix form is formulated using Lagrangian approach and the assumed mode method. The effects of the presence of intermediate point constraints in reducing the fluctuation of the contact force between the mass and the beam and the possible separation of the mass from the beam are investigated. The equation of motion and the numerical results are expressed in dimensionless form. The numerical results presented are therefore applicable for a large combination of system parameters.

보존적 중첩격자기법을 이용한 동적 플랩의 천이적 공력거동에 관한 수치적 연구 (Numerical Study on Transient Aerodynamics of Moving Flap Using Conservative Chimera Grid Method)

  • 최성욱;장근식;김인선
    • 한국전산유체공학회지
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    • 제5권2호
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    • pp.9-19
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    • 2000
  • Transient aerodynamic response of an airfoil to a moving plane-flap is numerically investigated using the two-dimensional Euler equations with conservative Chimera grid method. A body moving relative to a stationary grid is treated by an overset grid bounded by a 'Dynamic Domain Dividing Line' which has an advantage for constructing a well-defined hole-cutting boundary. A conservative Chimera grid method with the dynamic domain-dividing line technique is applied and validated by solving the flowfield around a circular cylinder moving supersonic speed. The unsteady and transient characteristics of the flow solver are also examined by computations of an oscillating airfoil and a ramp pitching airfoil respectively. The transient aerodynamic behavior of an airfoil with a moving plane-flap is analyzed for various flow conditions such as deflecting rate of flap and free stream Mach number.

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Consecutive-Frame Super-Resolution considering Moving Object Region

  • Cho, Sung Min;Jeong, Woo Jin;Jang, Kyung Hyun;Choi, Byung In;Moon, Young Shik
    • 한국컴퓨터정보학회논문지
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    • 제22권3호
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    • pp.45-51
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    • 2017
  • In this paper, we propose a consecutive-frame super-resolution method to tackle a moving object problem. The super-resolution is a method restoring a high resolution image from a low resolution image. The super-resolution is classified into two types, briefly, single-frame super-resolution and consecutive-frame super-resolution. Typically, the consecutive-frame super-resolution recovers a better than the single-frame super-resolution, because it use more information from consecutive frames. However, the consecutive-frame super-resolution failed to recover the moving object. Therefore, we proposed an improved method via moving object detection. Experimental results showed that the proposed method restored both the moving object and the background properly.

이동물체들의 Optical flow와 EMD 알고리즘을 이용한 식별과 Kalman 필터를 이용한 추적 (Detection using Optical Flow and EMD Algorithm and Tracking using Kalman Filter of Moving Objects)

  • 이정식;주영훈
    • 전기학회논문지
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    • 제64권7호
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    • pp.1047-1055
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    • 2015
  • We proposes a method for improving the identification and tracking of the moving objects in intelligent video surveillance system. The proposed method consists of 3 parts: object detection, object recognition, and object tracking. First of all, we use a GMM(Gaussian Mixture Model) to eliminate the background, and extract the moving object. Next, we propose a labeling technique forrecognition of the moving object. and the method for identifying the recognized object by using the optical flow and EMD algorithm. Lastly, we proposes method to track the location of the identified moving object regions by using location information of moving objects and Kalman filter. Finally, we demonstrate the feasibility and applicability of the proposed algorithms through some experiments.

Dynamics of an Axially Moving Bernoulli-Euler Beam: Spectral Element Modeling and Analysis

  • Hyungmi Oh;Lee, Usik;Park, Dong-Hyun
    • Journal of Mechanical Science and Technology
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    • 제18권3호
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    • pp.395-406
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    • 2004
  • The spectral element model is known to provide very accurate structural dynamic characteristics, while reducing the number of degree-of-freedom to resolve the computational and cost problems. Thus, the spectral element model for an axially moving Bernoulli-Euler beam subjected to axial tension is developed in the present paper. The high accuracy of the spectral element model is then verified by comparing its solutions with the conventional finite element solutions and exact analytical solutions. The effects of the moving speed and axial tension on the vibration characteristics, wave characteristics, and the static and dynamic stabilities of a moving beam are investigated.