The Experts below are selected from a list of 35526 Experts worldwide ranked by ideXlab platform

Shih-hsun Yin - One of the best experts on this subject based on the ideXlab platform.

  • Vibration of a Simple Beam Subjected to a Moving Sprung Mass with Initial Velocity and Constant Acceleration
    International Journal of Structural Stability and Dynamics, 2016
    Co-Authors: Shih-hsun Yin
    Abstract:

    In this paper, a semi-analytical solution to the problem of a simply supported beam subjected to a moving sprung mass with initial velocity and Constant Acceleration or deceleration was presented, which serves as a benchmark for checking the performance of other numerical methods. Herein, a finite element modeling procedure was adopted to tackle the vehicle–bridge interaction, and the responses of the vehicle and bridge were computed by time integration schemes such as the Newmark average Acceleration, HHT-α, and Wilson-θ methods. In comparison with the semi-analytical solution, the Acceleration response of the beam solved by the Newmark average Acceleration method shows spurious high-frequency oscillations caused by the finite element discretization. In contrast, the HHT-α and Wilson-θ methods can dissipate these oscillations and show more accurate results. Moreover, we found that the dynamic responses of the beam and sprung mass were mainly determined by the initial velocity of the sprung mass, but not ...

  • Vibration of a Simple Beam Subjected to a Moving Sprung Mass with Initial Velocity and Constant Acceleration
    International Journal of Structural Stability and Dynamics, 2016
    Co-Authors: Shih-hsun Yin
    Abstract:

    In this paper, a semi-analytical solution to the problem of a simply supported beam subjected to a moving sprung mass with initial velocity and Constant Acceleration or deceleration was presented, which serves as a benchmark for checking the performance of other numerical methods. Herein, a finite element modeling procedure was adopted to tackle the vehicle–bridge interaction, and the responses of the vehicle and bridge were computed by time integration schemes such as the Newmark average Acceleration, HHT-[Formula: see text], and Wilson-[Formula: see text] methods. In comparison with the semi-analytical solution, the Acceleration response of the beam solved by the Newmark average Acceleration method shows spurious high-frequency oscillations caused by the finite element discretization. In contrast, the HHT-[Formula: see text] and Wilson-[Formula: see text] methods can dissipate these oscillations and show more accurate results. Moreover, we found that the dynamic responses of the beam and sprung mass were mainly determined by the initial velocity of the sprung mass, but not by the Acceleration or deceleration.

Dominic James Farris - One of the best experts on this subject based on the ideXlab platform.

  • emulating Constant Acceleration locomotion mechanics on a treadmill
    Journal of Biomechanics, 2016
    Co-Authors: Dominic James Farris
    Abstract:

    Locomotion on an accelerating treadmill belt is not dynamically similar to overground Acceleration. The purpose of this study was to test if providing an external force to compensate for inertial forces during locomotion on an accelerating treadmill belt could induce locomotor dynamics similar to real Accelerations. Nine males (mean±sd age=26±4 years, mass=81±9kg, height=1.8±0.05m) began walking and transitioned to running on an accelerating instrumented treadmill belt at three Accelerations (0.27ms(-2), 0.42ms(-2), 0.76ms(-2)). Half the trials were typical treadmill locomotion (TT) and half were emulated Acceleration (EA), where elastic tubing harnessed to the participant provided a horizontal force equal to mass multiplied by Acceleration. Net mechanical work (WCOM) and ground reaction force impulses (IGRF) were calculated for individual steps and a linear regression was performed with these experimental measures as independent variables and theoretically derived values of work and impulse as predictor variables. For EA, linear fits were significant for WCOM (y=1.19x+10.5, P<0.001, R(2)=0.41) and IGRF (y=0.95x+8.1, P<0.001, R(2)=0.3). For TT, linear fits were not significant and explained virtually no variance for WCOM (y=0.06x+1.6, P=0.29, R(2)<0.01) and IGRF (y=0.10x+0.4, P=0.06, R(2)=0.01). This suggested that the EA condition was a better representation of real Acceleration dynamics than TT. Running steps from EA where work and impulse closely matched theoretical values showed similar adaptations to increasing Acceleration as have been previously observed overground (forward reorientation of GRF vector without an increase in magnitude or change in spatio-temporal metrics).

  • Emulating Constant Acceleration locomotion mechanics on a treadmill.
    Journal of Biomechanics, 2016
    Co-Authors: Dominic James Farris
    Abstract:

    Locomotion on an accelerating treadmill belt is not dynamically similar to overground Acceleration. The purpose of this study was to test if providing an external force to compensate for inertial forces during locomotion on an accelerating treadmill belt could induce locomotor dynamics similar to real Accelerations. Nine males (mean±sd age=26±4 years, mass=81±9kg, height=1.8±0.05m) began walking and transitioned to running on an accelerating instrumented treadmill belt at three Accelerations (0.27ms(-2), 0.42ms(-2), 0.76ms(-2)). Half the trials were typical treadmill locomotion (TT) and half were emulated Acceleration (EA), where elastic tubing harnessed to the participant provided a horizontal force equal to mass multiplied by Acceleration. Net mechanical work (WCOM) and ground reaction force impulses (IGRF) were calculated for individual steps and a linear regression was performed with these experimental measures as independent variables and theoretically derived values of work and impulse as predictor variables. For EA, linear fits were significant for WCOM (y=1.19x+10.5, P

Anaël Grandjean - One of the best experts on this subject based on the ideXlab platform.

  • Constant Acceleration Theorem for Extended von Neumann Neighbourhoods
    2016
    Co-Authors: Anaël Grandjean
    Abstract:

    We study 2-dimensional cellular automata as language recog-nizers. We are looking for closure properties, similar to the one existing in one dimension. Some results are already known for the most used neighbourhoods, however many problems remain open concerning more general neighbourhoods. In this paper we provide a construction to prove a Constant Acceleration theorem for extended von Neumann neighbourhoods. We then use this theorem and some classical tools to prove the equivalence of those neighbourhoods, considering the set of languages recognizable in real time.

  • Automata - Constant Acceleration Theorem for Extended von Neumann Neighbourhoods
    Cellular Automata and Discrete Complex Systems, 2016
    Co-Authors: Anaël Grandjean
    Abstract:

    We study 2-dimensional cellular automata as language recog-nizers. We are looking for closure properties, similar to the one existing in one dimension. Some results are already known for the most used neighbourhoods, however many problems remain open concerning more general neighbourhoods. In this paper we provide a construction to prove a Constant Acceleration theorem for extended von Neumann neighbourhoods. We then use this theorem and some classical tools to prove the equivalence of those neighbourhoods, considering the set of languages recognizable in real time.

Joon Lyou - One of the best experts on this subject based on the ideXlab platform.

  • trajectory generation with piecewise Constant Acceleration and tracking control of a quadcopter
    International Conference on Industrial Technology, 2015
    Co-Authors: Jong Tai Jang, Sung Tae Moon, Sanghyuck Han, Hyeon Cheol Gong, Gihyuk Choi, In Hee Hwang, Joon Lyou
    Abstract:

    This paper describes a 3D reference trajectory generation and tracking control method for a quadcopter. The flying trajectory is a piecewise curve that passes through viapoints at specified times or speeds and has Constant Acceleration within each interval. The path is first represented as the third degree polynomials, and to overcome demerits of the C-splines, a numeric algorithm is suggested and implemented. The feasibility of the generated trajectory is checked by nonlinear dynamics model of a quadcopter. After executing several flying experiments for a quadcopter, tracking errors are evaluated.

  • ICIT - Trajectory generation with piecewise Constant Acceleration and tracking control of a quadcopter
    2015 IEEE International Conference on Industrial Technology (ICIT), 2015
    Co-Authors: Jong Tai Jang, Sung Tae Moon, Sanghyuck Han, Hyeon Cheol Gong, Gihyuk Choi, In Hee Hwang, Joon Lyou
    Abstract:

    This paper describes a 3D reference trajectory generation and tracking control method for a quadcopter. The flying trajectory is a piecewise curve that passes through viapoints at specified times or speeds and has Constant Acceleration within each interval. The path is first represented as the third degree polynomials, and to overcome demerits of the C-splines, a numeric algorithm is suggested and implemented. The feasibility of the generated trajectory is checked by nonlinear dynamics model of a quadcopter. After executing several flying experiments for a quadcopter, tracking errors are evaluated.

Sun Peng - One of the best experts on this subject based on the ideXlab platform.

  • Adaptive Constant Acceleration model and tracking algorithm based on strong tracking filter
    Systems Engineering - Theory & Practice, 2008
    Co-Authors: Sun Peng
    Abstract:

    In sensor target tracking and data processing,building a dynamic model of target motion plays an important role.In order to overcome the shortcomings of Current Statistical Model for non-maneuvering targets and Constant Acceleration model for maneuvering targets,by researching Current Statistical Model and Constant Acceleration model for target tracking,a adaptive Constant Acceleration model and tracking algorithm(ACA-STF) is presented.By using a difference between the value of speed prediction and estimation which adaptively adjust its the covariance matrix of process noise and introducing a fading factor of Strong Tracking Filter(STF),this algorithm can improve greatly the adaptive tracking performance to track robust maneuvering target,and has better tracking performance to track common maneuvering targets.The theoretic analyses and simulation results show this algorithm has better tracking performance to track non-maneuvering targets and maneuvering targets than CS algorithm.