By combining fractal theory with D-S evidence theory, an algorithm based on the fusion of multi-fractal features is presented. Fractal features are extracted, and basic probability assignment function is designed. Com...By combining fractal theory with D-S evidence theory, an algorithm based on the fusion of multi-fractal features is presented. Fractal features are extracted, and basic probability assignment function is designed. Comparison and simulation are performed on the new algorithm, the old algorithm based on single feature and the algorithm based on neural network. Results of the comparison and simulation illustrate that the new algorithm is feasible and valid.展开更多
Eased on the mechanism of temperature tactile sensing of human finger,a heat flux tactile sensor com- posed of a thermostat module and a heat flux sensor is designed to identify material thermal properties. The ther- ...Eased on the mechanism of temperature tactile sensing of human finger,a heat flux tactile sensor com- posed of a thermostat module and a heat flux sensor is designed to identify material thermal properties. The ther- mostat module maintains the sensor temperature invariable, and the heat flux sensor（Peltier device） detects the heat flux temperature difference between the thermostat module and the object surface. Two different modes of the heat flux tactile sensor are proposed, and they are simulated and experimented for different material objects. The results indicate that the heat flux tactile sensor can effectively identify different thermal properties.展开更多
Many vehicle platoons are interrupted while traveling on roads,especially at urban signalized intersections.One reason for such interruptions is the inability to exchange real-time information between traditional huma...Many vehicle platoons are interrupted while traveling on roads,especially at urban signalized intersections.One reason for such interruptions is the inability to exchange real-time information between traditional human-driven vehicles and intersection infrastructure.Thus,this paper develops a Markov chain-based model to recognize platoons.A simulation experiment is performed in Vissim based on field data extracted from video recordings to prove the model’s applicability.The videos,recorded with a high-definition camera,contain field driving data from three Tesla vehicles,which can achieve Level 2 autonomous driving.The simulation results show that the recognition rate exceeds 80%when the connected and autonomous vehicle penetration rate is higher than 0.7.Whether a vehicle is upstream or downstream of an intersection also affects the performance of platoon recognition.The platoon recognition model developed in this paper can be used as a signal control input at intersections to reduce the unnecessary interruption of vehicle platoons and improve traffic efficiency.展开更多
Dynamics and vibration of control valves under flow-induced vibration are analyzed. Hydrodynamic load characteristics and structural response under flow-induced vibration are mainly influenced by inertia, damping, ela...Dynamics and vibration of control valves under flow-induced vibration are analyzed. Hydrodynamic load characteristics and structural response under flow-induced vibration are mainly influenced by inertia, damping, elastic, geometric characteristics and hydraulic parameters. The purpose of this work is to investigate the dynamic behavior of control valves in the response to self-excited fluid flow. An analytical and numerical method is developed to simulate the dynamic and vibrational behavior of sliding dam valves, in response to flow excitation. In order to demonstrate the effectiveness of proposed model, the simulation results are validated with experimental ones. Finally, to achieve the optimal valve geometry, numerical results for various shapes of valves are compared. Rounded valve with the least amount of flow turbulence obtains lower fluctuations and vibration amplitude compared with the flat and steep valves. Simulation results demonstrate that with the optimal design requirements of valves, vibration amplitude can be reduced by an average to 30%.展开更多
The operating principle of an antilock braking system （ABS） is it compares current value of angular acceleration with the threshold value. The advantage of such system is that enough it has only the angular velocity...The operating principle of an antilock braking system （ABS） is it compares current value of angular acceleration with the threshold value. The advantage of such system is that enough it has only the angular velocity sensors. The disadvantage is successive overshoot, i. e. successive transition from wheels locking mode to wheels rolling mode. So braking mechanism can’ t realize the maximum possible torque in the current road conditions. The idea of increasing the braking effectiveness is the intensity of rising pressure depends on the road conditions. The problem is the torque produced by braking mechanism, current road conditions and the value of traction coefficient is unknown For evaluation of these parameters built and training three neural networks. A simulator of random road condition＇s variation was built to test adequacy of the control unites operation in close to real conditions.展开更多
This paper presents a design for a self-powered radio frequency identification (RFID) tag with a thin film bulk acoustic reso- nating piezoelectric power supply (PPS), which can be used for portable remote temperature...This paper presents a design for a self-powered radio frequency identification (RFID) tag with a thin film bulk acoustic reso- nating piezoelectric power supply (PPS), which can be used for portable remote temperature monitoring. We call this system a PPS-RFID for short. The RFID systems have been found to have many applications in the internet of things (IOT) in the past decade. But semi-active RFID tags require an onboard battery which limits their applications in many fields. For these reasons, our research focuses on power sources for the RFID tags. This paper emphasizes the circuit design and simulation of PPS. In our tests, 0.283 mW was generated by PPS at 1 Hz vibration by a 650 N impact force. The results showed that the integrated PPS could supply sufficient power for the designed PPS-RFID tag. The PPS-RFID tag can be widely used for temperature monitoring during mobile transport of perishable items such as medicines or food.展开更多
文摘By combining fractal theory with D-S evidence theory, an algorithm based on the fusion of multi-fractal features is presented. Fractal features are extracted, and basic probability assignment function is designed. Comparison and simulation are performed on the new algorithm, the old algorithm based on single feature and the algorithm based on neural network. Results of the comparison and simulation illustrate that the new algorithm is feasible and valid.
基金Supported by the National High Technology Research and Development Program of China(″863″Program)(2009AA01Z314,2009AA01Z311)the Jiangsu Province Natural Science Foundation(BK2009272)theJiangsu Province″333″Program~~
文摘Eased on the mechanism of temperature tactile sensing of human finger,a heat flux tactile sensor com- posed of a thermostat module and a heat flux sensor is designed to identify material thermal properties. The ther- mostat module maintains the sensor temperature invariable, and the heat flux sensor（Peltier device） detects the heat flux temperature difference between the thermostat module and the object surface. Two different modes of the heat flux tactile sensor are proposed, and they are simulated and experimented for different material objects. The results indicate that the heat flux tactile sensor can effectively identify different thermal properties.
基金Project(71871013)supported by the National Natural Science Foundation of China。
文摘Many vehicle platoons are interrupted while traveling on roads,especially at urban signalized intersections.One reason for such interruptions is the inability to exchange real-time information between traditional human-driven vehicles and intersection infrastructure.Thus,this paper develops a Markov chain-based model to recognize platoons.A simulation experiment is performed in Vissim based on field data extracted from video recordings to prove the model’s applicability.The videos,recorded with a high-definition camera,contain field driving data from three Tesla vehicles,which can achieve Level 2 autonomous driving.The simulation results show that the recognition rate exceeds 80%when the connected and autonomous vehicle penetration rate is higher than 0.7.Whether a vehicle is upstream or downstream of an intersection also affects the performance of platoon recognition.The platoon recognition model developed in this paper can be used as a signal control input at intersections to reduce the unnecessary interruption of vehicle platoons and improve traffic efficiency.
文摘Dynamics and vibration of control valves under flow-induced vibration are analyzed. Hydrodynamic load characteristics and structural response under flow-induced vibration are mainly influenced by inertia, damping, elastic, geometric characteristics and hydraulic parameters. The purpose of this work is to investigate the dynamic behavior of control valves in the response to self-excited fluid flow. An analytical and numerical method is developed to simulate the dynamic and vibrational behavior of sliding dam valves, in response to flow excitation. In order to demonstrate the effectiveness of proposed model, the simulation results are validated with experimental ones. Finally, to achieve the optimal valve geometry, numerical results for various shapes of valves are compared. Rounded valve with the least amount of flow turbulence obtains lower fluctuations and vibration amplitude compared with the flat and steep valves. Simulation results demonstrate that with the optimal design requirements of valves, vibration amplitude can be reduced by an average to 30%.
文摘The operating principle of an antilock braking system （ABS） is it compares current value of angular acceleration with the threshold value. The advantage of such system is that enough it has only the angular velocity sensors. The disadvantage is successive overshoot, i. e. successive transition from wheels locking mode to wheels rolling mode. So braking mechanism can’ t realize the maximum possible torque in the current road conditions. The idea of increasing the braking effectiveness is the intensity of rising pressure depends on the road conditions. The problem is the torque produced by braking mechanism, current road conditions and the value of traction coefficient is unknown For evaluation of these parameters built and training three neural networks. A simulator of random road condition＇s variation was built to test adequacy of the control unites operation in close to real conditions.
基金supported by the MEMS subject construction fund of the Kunming University of Science and Technology (Grant No. 14078024)
文摘This paper presents a design for a self-powered radio frequency identification (RFID) tag with a thin film bulk acoustic reso- nating piezoelectric power supply (PPS), which can be used for portable remote temperature monitoring. We call this system a PPS-RFID for short. The RFID systems have been found to have many applications in the internet of things (IOT) in the past decade. But semi-active RFID tags require an onboard battery which limits their applications in many fields. For these reasons, our research focuses on power sources for the RFID tags. This paper emphasizes the circuit design and simulation of PPS. In our tests, 0.283 mW was generated by PPS at 1 Hz vibration by a 650 N impact force. The results showed that the integrated PPS could supply sufficient power for the designed PPS-RFID tag. The PPS-RFID tag can be widely used for temperature monitoring during mobile transport of perishable items such as medicines or food.
