The problem of water resources has become a bottleneck for the sustainable development of Beijing and Hebei Province (the two regions together are called "Jingji Region" for short).It is imperative to establ...The problem of water resources has become a bottleneck for the sustainable development of Beijing and Hebei Province (the two regions together are called "Jingji Region" for short).It is imperative to establish an effective and equitable water resources ecological compensation (eco-compensation) mechanism.The three stages of water resources eco-compensation are expatiated here namely the eco-compensation missing stage,ecocompensation start stage and the eco-compensation development stage.Through the establishment of eco-compensation game model based on the game theory,the reasons of the formation for the three stages were analyzed,as well as the conversion conditions from non-cooperative game to cooperative game among the related stakeholders including the central government,the water recipient government and the water source government.Furthermore,this study pointed out that the water resources eco-compensation in Jingji Region was not established based on the institution,but formed and developed in coping with the challenges of water crisis.However,institution construction is quite essential in game process for the water recipient government and the water source government.Finally recommendations in four areas including legalization of eco-compensation mechanism,setting up compensation standards,leading industrial upgrading and developing related incentives and constraints were concluded.展开更多
This paper presents an adaptive friction compensation method based on LuGre model for large diameter electric-hydraulic proportional valves in which the valve core contains friction.A mathematic model of the electric-...This paper presents an adaptive friction compensation method based on LuGre model for large diameter electric-hydraulic proportional valves in which the valve core contains friction.A mathematic model of the electric-hydraulic proportional valve is established,and the friction characteristics are described based on the LuGre model.The global asymptotic stability of the control system with the adaptive friction compensation controller is guaranteed over Lyapunov theorem.The adaptive compensation of the friction on LuGre friction model is verified by simulation and experiment.The steady-state error is about [-4.23 × 10^(-5)m,5.91 × 10^(-5)m]and[-2.5 × 10^(-4)m,2.6 ×10^(-4) m] on simulation and experiment,the position tracking accuracy is higher,and the lag time of the main valve through the dead zone is shorter.The result proves that the adaptive friction compensation method can effectively compensate for the negative effects of nonlinear friction.展开更多
基金sponsored by the program of CDRF-GM Young Professionals in Development Study (PHD Dissertations Fellowship) set by China Development Research Foundation in 2009
文摘The problem of water resources has become a bottleneck for the sustainable development of Beijing and Hebei Province (the two regions together are called "Jingji Region" for short).It is imperative to establish an effective and equitable water resources ecological compensation (eco-compensation) mechanism.The three stages of water resources eco-compensation are expatiated here namely the eco-compensation missing stage,ecocompensation start stage and the eco-compensation development stage.Through the establishment of eco-compensation game model based on the game theory,the reasons of the formation for the three stages were analyzed,as well as the conversion conditions from non-cooperative game to cooperative game among the related stakeholders including the central government,the water recipient government and the water source government.Furthermore,this study pointed out that the water resources eco-compensation in Jingji Region was not established based on the institution,but formed and developed in coping with the challenges of water crisis.However,institution construction is quite essential in game process for the water recipient government and the water source government.Finally recommendations in four areas including legalization of eco-compensation mechanism,setting up compensation standards,leading industrial upgrading and developing related incentives and constraints were concluded.
基金Supported by the National Key Basic Research Program of China(No.2014CB046405)Key Projects in the National Science&Technology Pillar Program during the Twelfth Five-year Plan of China(No.2014BAF02B00,2011BAF09B04)
文摘This paper presents an adaptive friction compensation method based on LuGre model for large diameter electric-hydraulic proportional valves in which the valve core contains friction.A mathematic model of the electric-hydraulic proportional valve is established,and the friction characteristics are described based on the LuGre model.The global asymptotic stability of the control system with the adaptive friction compensation controller is guaranteed over Lyapunov theorem.The adaptive compensation of the friction on LuGre friction model is verified by simulation and experiment.The steady-state error is about [-4.23 × 10^(-5)m,5.91 × 10^(-5)m]and[-2.5 × 10^(-4)m,2.6 ×10^(-4) m] on simulation and experiment,the position tracking accuracy is higher,and the lag time of the main valve through the dead zone is shorter.The result proves that the adaptive friction compensation method can effectively compensate for the negative effects of nonlinear friction.
