The Experts below are selected from a list of 306 Experts worldwide ranked by ideXlab platform
Yu Jen Wang - One of the best experts on this subject based on the ideXlab platform.
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Design of a weighted-rotor energy harvester based on dynamic analysis and optimization of circular halbach array magnetic disk
Micromachines, 2015Co-Authors: Yu Jen Wang, Yu Ti Hao, Hao Yu LinAbstract:This paper proposes the design of a weighted-rotor energy harvester (WREH) in which the oscillation is caused by the periodic change of the tangential component of gravity, to harvest kinetic energy from a Rotating Wheel. When a WREH is designed with a suitable characteristic length, the rotor’s natural frequency changes according to the Wheel rotation speed and the rotor oscillates at a wide angle and high angular velocity to generate a large amount of power. The magnetic disk is designed according to an optimized circular Halbach array. The optimized circular Halbach array magnetic disk provides the largest induced EMF for different sector-angle ratios for the same magnetic disk volume. This study examined the output voltage and power by considering the constant and accelerating plate-rotation speeds, respectively. This paper discusses the effects of the angular acceleration speed of a Rotating Wheel corresponding to the dynamic behaviors of a weighted rotor. The average output power is 399 to 535 microwatts at plate-rotation speeds from 300 to 500 rpm, enabling the WREH to be a suitable power source for a tire-pressure monitoring system.
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IECON - Design of weighted type energy harvester based on analysis of a wireless tire pressure monitor system
IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society, 2014Co-Authors: Yu Jen Wang, Hao Yu LinAbstract:This paper proposes the design of a novel weighted-rotor energy harvester, which oscillates due to the periodic change of the tangential component of gravity, to harvest kinetic energy from a Rotating Wheel. Unlike traditional energy-harvesting devices, which have a fixed natural frequency, when the speed of the car increases, the centripetal acceleration of the Rotating Wheel also increases the rotor's natural frequency of oscillation. By employing a suitably-designed weight, the natural frequency of the rotor can match with the Rotating frequency of the Wheel at any speed, and the rotor oscillates at a large angle and angular velocity to generate a large amount of power. The models of power generation were derived by using Faraday's law of induction and Lorentz force law, which were followed by the numerical simulation performed to verify the correctness with experiments. The output voltage and power have been discussed considering the constant and accelerating plate rotation speed. When a 550 ohm resistor connected in series, the average output power is 399 to 535 micro-Watts at plate rotation speed from 300 to 500 rpm and is possible to be the power source for TPMS.
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system design of a weighted pendulum type electromagnetic generator for harvesting energy from a Rotating Wheel
IEEE-ASME Transactions on Mechatronics, 2013Co-Authors: Yu Jen Wang, Chungde Chen, Chengkuo SungAbstract:This paper proposes the system design of a weighted-pendulum-type electromagnetic generator for harvesting energy from a Rotating Wheel. Different from the traditional energy-harvesting device, the natural frequency of the suitable weighted pendulum, which oscillates due to periodic change of the tangential component of gravitational force, can match up with the rotational frequency of the Wheel at any speed. In addition, the pendulum oscillates at a large angle and angular velocity so as to generate a large amount of power. The physical model of the pendulum was first constructed and the equation of motion was then derived via the Lagrange method. Then, the models of power generation were derived by using Faraday's law of induction and the Lorentz force law. The nonlinear dynamic behaviors were discussed considering the characteristic length, variable electromagnetic damping, and Wheel rotation speed. Finally, an experimental rig was constructed to verify the correctness of numerical results. The suitable weighted pendulum combined with coils and magnets has demonstrated the power generation of several hundred micro-Watts in the experiment.
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design of a frequency adjusting device for harvesting energy from a Rotating Wheel
Sensors and Actuators A-physical, 2010Co-Authors: Yu Jen Wang, Chungde Chen, Chengkuo SungAbstract:Abstract This study designed a well-weighted pendulum to harvest energy from a Rotating Wheel, which consisted of a pendulum and one or more weights. In general, a pendulum cannot oscillate with a large angle at any Wheel speed. In this study, three well-designed weights helped the pendulum to adjust its natural frequency to meet the Wheel rotation frequency. Therefore, the well-weighted pendulum is able to oscillate at various Wheel speeds with a large angle and a high velocity. The kinetic energy produced was converted into electrical energy by electromagnetic induction, and a numerical study revealed that the well-weighted pendulum generated a power of several milli-Watts. The numerical results obtained using the analytical model of the well-weighted pendulum were in good agreement with the experimental results. The swing angle of the weighted pendulum was close to 43° at a Wheel rotation speed of 350 rpm, 8 times that of the ill-weighted pendulum, verifying that the well-weighted pendulum oscillated at larger angles.
Noël Midoux - One of the best experts on this subject based on the ideXlab platform.
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Particle dispersion in the near-wake of an isolated Rotating Wheel: Experimental and CFD study
Journal of Aerosol Science, 2014Co-Authors: Fabien Gérardin, Caroline Gentric, Noël MidouxAbstract:The aim of the present study is the characterisation of the fine particle dispersion in the wake of an isolated Wheel of vehicle. The work performed in this study lies within the description and the understanding of the transport of re-suspended road dust emissions induced by the circulation of vehicles. The behaviour of PM2.5 fraction in the field near to the Wheel was investigated for two Rotating velocities and two types of tyres, both experimentally and using Computational Fluid Dynamics (CFD). Experiments were carried out in a wind tunnel equipped by moving ground with carefully controlled aerodynamic conditions. CFD methods were used to calculate the velocity field of the air flow around a Rotating Wheel and to determine the trajectories for different particle sizes. The experiments reveal a strong impact of the nature of tyre both on the velocity field of the flow and the particle dispersion in the near wake of the Wheel. In this simple case of an isolated Wheel, the simulated flow was quite similar to the corresponding experimental results, although prediction of the flow located in the region of the point of contact between the Wheel and the ground could be improved.
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Particle dispersion in the near-wake of an isolated Rotating Wheel: Experimental and CFD study
Journal of Aerosol Science, 2014Co-Authors: Fabien Gérardin, Caroline Gentric, Noël MidouxAbstract:International audienceThe aim of the present study is the characterisation of the fine particle dispersion in the wake of an isolated Wheel of vehicle. The work performed in this study lies within the description and the understanding of the transport of re-suspended road dust emissions induced by the circulation of vehicles. The behaviour of PM2.5 fraction in the field near to the Wheel was investigated for two Rotating velocities and two types of tyres, both experimentally and using Computational Fluid Dynamics (CFD). Experiments were carried out in a wind tunnel equipped by moving ground with carefully controlled aerodynamic conditions. CFD methods were used to calculate the velocity field of the air flow around a Rotating Wheel and to determine the trajectories for different particle sizes. The experiments reveal a strong impact of the nature of tyre both on the velocity field of the flow and the particle dispersion in the near wake of the Wheel. In this simple case of an isolated Wheel, the simulated flow was quite similar to the corresponding experimental results, although prediction of the flow located in the region of the point of contact between the Wheel and the ground could be improved
Chengkuo Sung - One of the best experts on this subject based on the ideXlab platform.
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system design of a weighted pendulum type electromagnetic generator for harvesting energy from a Rotating Wheel
IEEE-ASME Transactions on Mechatronics, 2013Co-Authors: Yu Jen Wang, Chungde Chen, Chengkuo SungAbstract:This paper proposes the system design of a weighted-pendulum-type electromagnetic generator for harvesting energy from a Rotating Wheel. Different from the traditional energy-harvesting device, the natural frequency of the suitable weighted pendulum, which oscillates due to periodic change of the tangential component of gravitational force, can match up with the rotational frequency of the Wheel at any speed. In addition, the pendulum oscillates at a large angle and angular velocity so as to generate a large amount of power. The physical model of the pendulum was first constructed and the equation of motion was then derived via the Lagrange method. Then, the models of power generation were derived by using Faraday's law of induction and the Lorentz force law. The nonlinear dynamic behaviors were discussed considering the characteristic length, variable electromagnetic damping, and Wheel rotation speed. Finally, an experimental rig was constructed to verify the correctness of numerical results. The suitable weighted pendulum combined with coils and magnets has demonstrated the power generation of several hundred micro-Watts in the experiment.
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design of a frequency adjusting device for harvesting energy from a Rotating Wheel
Sensors and Actuators A-physical, 2010Co-Authors: Yu Jen Wang, Chungde Chen, Chengkuo SungAbstract:Abstract This study designed a well-weighted pendulum to harvest energy from a Rotating Wheel, which consisted of a pendulum and one or more weights. In general, a pendulum cannot oscillate with a large angle at any Wheel speed. In this study, three well-designed weights helped the pendulum to adjust its natural frequency to meet the Wheel rotation frequency. Therefore, the well-weighted pendulum is able to oscillate at various Wheel speeds with a large angle and a high velocity. The kinetic energy produced was converted into electrical energy by electromagnetic induction, and a numerical study revealed that the well-weighted pendulum generated a power of several milli-Watts. The numerical results obtained using the analytical model of the well-weighted pendulum were in good agreement with the experimental results. The swing angle of the weighted pendulum was close to 43° at a Wheel rotation speed of 350 rpm, 8 times that of the ill-weighted pendulum, verifying that the well-weighted pendulum oscillated at larger angles.
Fabien Gérardin - One of the best experts on this subject based on the ideXlab platform.
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Particle dispersion in the near-wake of an isolated Rotating Wheel: Experimental and CFD study
Journal of Aerosol Science, 2014Co-Authors: Fabien Gérardin, Caroline Gentric, Noël MidouxAbstract:The aim of the present study is the characterisation of the fine particle dispersion in the wake of an isolated Wheel of vehicle. The work performed in this study lies within the description and the understanding of the transport of re-suspended road dust emissions induced by the circulation of vehicles. The behaviour of PM2.5 fraction in the field near to the Wheel was investigated for two Rotating velocities and two types of tyres, both experimentally and using Computational Fluid Dynamics (CFD). Experiments were carried out in a wind tunnel equipped by moving ground with carefully controlled aerodynamic conditions. CFD methods were used to calculate the velocity field of the air flow around a Rotating Wheel and to determine the trajectories for different particle sizes. The experiments reveal a strong impact of the nature of tyre both on the velocity field of the flow and the particle dispersion in the near wake of the Wheel. In this simple case of an isolated Wheel, the simulated flow was quite similar to the corresponding experimental results, although prediction of the flow located in the region of the point of contact between the Wheel and the ground could be improved.
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Particle dispersion in the near-wake of an isolated Rotating Wheel: Experimental and CFD study
Journal of Aerosol Science, 2014Co-Authors: Fabien Gérardin, Caroline Gentric, Noël MidouxAbstract:International audienceThe aim of the present study is the characterisation of the fine particle dispersion in the wake of an isolated Wheel of vehicle. The work performed in this study lies within the description and the understanding of the transport of re-suspended road dust emissions induced by the circulation of vehicles. The behaviour of PM2.5 fraction in the field near to the Wheel was investigated for two Rotating velocities and two types of tyres, both experimentally and using Computational Fluid Dynamics (CFD). Experiments were carried out in a wind tunnel equipped by moving ground with carefully controlled aerodynamic conditions. CFD methods were used to calculate the velocity field of the air flow around a Rotating Wheel and to determine the trajectories for different particle sizes. The experiments reveal a strong impact of the nature of tyre both on the velocity field of the flow and the particle dispersion in the near wake of the Wheel. In this simple case of an isolated Wheel, the simulated flow was quite similar to the corresponding experimental results, although prediction of the flow located in the region of the point of contact between the Wheel and the ground could be improved
Ramalingam Vetrivelan - One of the best experts on this subject based on the ideXlab platform.
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Roles of motor and cortical activity in sleep rebound in rat
The European journal of neuroscience, 2020Co-Authors: Yujun Wen, Jianguo Niu, Christopher Xin, Li Cui, Ramalingam VetrivelanAbstract:Sleep pressure that builds up gradually during the extended wakefulness results in sleep rebound. Several lines of evidence, however, suggest that wake per se may not be sufficient to drive sleep rebound and that rapid eye movement (REM) and non-rapid eye movement (NREM) sleep rebound may be differentially regulated. In this study, we investigated the relative contribution of brain versus physical activities in REM and NREM sleep rebound by four sets of experiments. First, we forced locomotion in rats in a Rotating Wheel for 4 hr and examined subsequent sleep rebound. Second, we exposed the rats lacking homeostatic sleep response after prolonged quiet wakefulness and arousal brain activity induced by chemoactivation of parabrachial nucleus to the same Rotating Wheel paradigm and tested if physical activity could rescue the sleep homeostasis. Third, we varied motor activity levels while concurrently inhibiting the cortical activity by administering ketamine or xylazine (motor inhibitor), or ketamine + xylazine mixture and investigated if motor activity in the absence of activated cortex can cause NREM sleep rebound. Fourth and finally, we manipulated cortical activity by administering ketamine (that induced active wakefulness and waking brain) alone or in combination with atropine (that selectively inhibits the cortex) and studied if cortical inhibition irrespective of motor activity levels can block REM sleep rebound. Our results demonstrate that motor activity but not cortical activity determines NREM sleep rebound whereas cortical activity but not motor activity determines REM sleep rebound.
