The present paper investigates the existence of chaos in a non-autonomous fractional-order micro-electromechanical resonator system（FOMEMRS）.Using the maximal Lyapunov exponent criterion,we show that the FOMEMRS exh...The present paper investigates the existence of chaos in a non-autonomous fractional-order micro-electromechanical resonator system（FOMEMRS）.Using the maximal Lyapunov exponent criterion,we show that the FOMEMRS exhibits chaos.Strange attractors of the system are plotted to validate its chaotic behavior.Afterward,a novel fractional finite-time controller is introduced to suppress the chaos of the FOMEMRS with model uncertainties and external disturbances in a given finite time.Using the latest version of the fractional Lyapunov theory,the finite time stability and robustness of the proposed scheme are proved.Finally,we present some computer simulations to illustrate the usefulness and applicability of the proposed method.展开更多
Objective:A novel portable and intelligent fluid resuscitation infuser is proposed in this paper. It satisfies the demands of long time use in harsh environment, such as traffic accident, natural disaster, battlefield...Objective:A novel portable and intelligent fluid resuscitation infuser is proposed in this paper. It satisfies the demands of long time use in harsh environment, such as traffic accident, natural disaster, battlefield, evacuation, pre-hospital emergency and so on. Methods:Miniature linear motor and liquid blood cartridge compose the pump body. It's based on the biological impedance method to measure and control, which resolve the disadvantage of traditional infuser device:large power dissipation, big size, AC power supply only and can't be use in field. The whole device weights 250 gram and sizes as two mobile phone together. Results:Model device experiment shows:six number 7 standard AAA size alkaline batteries will run the pump for approximately 8-10 h at 6 liters per hour; IV bag can be placed at any position of patient, even under the stretcher. Conclusion:It provides accurate and reliable intravenous infusion for first-aid treatment in展开更多
This paper addresses a nonlinear feedback control problem for the chaotic arch micro- electro-mechanical system with unknown parameters,immeasurable states and partial state-constraint subjected to the distributed ele...This paper addresses a nonlinear feedback control problem for the chaotic arch micro- electro-mechanical system with unknown parameters,immeasurable states and partial state-constraint subjected to the distributed electrostatic actuation.To reflect inherent properties and design controller, the phase diagrams,bifurcation diagram and Poincare section are presented to investigate the nonlinear dynamics.The authors employ a symmetric barrier Lyapunov function to prevent violation of constraint when the arch micro-electro-mechanical system faces some limits.An RBF neural network system integrating with an update law is adopted to estimate unknown function with arbitrarily small error. To eliminate chaotic oscillation,a neuro-adaptive backstepping control scheme fused with an extended state tracking differentiator and an observer is constructed to lower requirements on measured states and precise system model.Besides,introducing an extended state tracking differentiator avoids repeated derivative for the virtual control signal associated with conventional backstepping.Finally,simulation results are presented to illustrate feasibility of the proposed scheme.展开更多
文摘The present paper investigates the existence of chaos in a non-autonomous fractional-order micro-electromechanical resonator system（FOMEMRS）.Using the maximal Lyapunov exponent criterion,we show that the FOMEMRS exhibits chaos.Strange attractors of the system are plotted to validate its chaotic behavior.Afterward,a novel fractional finite-time controller is introduced to suppress the chaos of the FOMEMRS with model uncertainties and external disturbances in a given finite time.Using the latest version of the fractional Lyapunov theory,the finite time stability and robustness of the proposed scheme are proved.Finally,we present some computer simulations to illustrate the usefulness and applicability of the proposed method.
基金Supported by the Second Batch of Projects of Army Medical Eleventh Five-Year Plan Research(08G084)Chongqing Key Scientific and Technological Projects(CSTC,2008AC5120)
文摘Objective:A novel portable and intelligent fluid resuscitation infuser is proposed in this paper. It satisfies the demands of long time use in harsh environment, such as traffic accident, natural disaster, battlefield, evacuation, pre-hospital emergency and so on. Methods:Miniature linear motor and liquid blood cartridge compose the pump body. It's based on the biological impedance method to measure and control, which resolve the disadvantage of traditional infuser device:large power dissipation, big size, AC power supply only and can't be use in field. The whole device weights 250 gram and sizes as two mobile phone together. Results:Model device experiment shows:six number 7 standard AAA size alkaline batteries will run the pump for approximately 8-10 h at 6 liters per hour; IV bag can be placed at any position of patient, even under the stretcher. Conclusion:It provides accurate and reliable intravenous infusion for first-aid treatment in
基金supported by the National Natural Science Foundation of China under Grant Nos.51505170,51475097 and 51505045Basic and Frontier Research Program of Chongqing Municipality under Grant Nos.cstc2016jcyjA0584 and cstc2016jcyjA0441)+1 种基金Project of Introduction of Talents of Guizhou University(No.[2017]27)Key Scientific Research Program of Guizhou Province under Grant No.[2017]3001)
文摘This paper addresses a nonlinear feedback control problem for the chaotic arch micro- electro-mechanical system with unknown parameters,immeasurable states and partial state-constraint subjected to the distributed electrostatic actuation.To reflect inherent properties and design controller, the phase diagrams,bifurcation diagram and Poincare section are presented to investigate the nonlinear dynamics.The authors employ a symmetric barrier Lyapunov function to prevent violation of constraint when the arch micro-electro-mechanical system faces some limits.An RBF neural network system integrating with an update law is adopted to estimate unknown function with arbitrarily small error. To eliminate chaotic oscillation,a neuro-adaptive backstepping control scheme fused with an extended state tracking differentiator and an observer is constructed to lower requirements on measured states and precise system model.Besides,introducing an extended state tracking differentiator avoids repeated derivative for the virtual control signal associated with conventional backstepping.Finally,simulation results are presented to illustrate feasibility of the proposed scheme.
