Engine-variable pump-variable motor drive system is a complex nonlinear system. In order to improve system response speed and stability,a sliding-mode variable-structure control based on a feedback linearization theor...Engine-variable pump-variable motor drive system is a complex nonlinear system. In order to improve system response speed and stability,a sliding-mode variable-structure control based on a feedback linearization theory is analyzed in this research. A standardized system model is established and linearized by the feedback linearization theory,and the input dimension is reduced through the relationship between variables which has simplified the linearization process. Then the sliding-mode controller using an exponential reaching law is designed and the Lyapunov stability of this algorithm is verified. The simulation results show that the sliding-mode variable-structure controller based on the feedback linearization theory can improve system response speed,reduce overshoot and achieve stronger robustness,so the vehicle speed control requirements can be satisfied well.展开更多
Fe 100- x Ni x alloys of ultrafine particle with the average grain size of about 10 nm were synthesized by mechanically alloying process. The samples were investigated by X ray diffraction and measure...Fe 100- x Ni x alloys of ultrafine particle with the average grain size of about 10 nm were synthesized by mechanically alloying process. The samples were investigated by X ray diffraction and measurements of the saturation magnetization and coercivity force. Both b.c.c and f.c.c phase exist within a wide range for Fe 100- x Ni x , while x ≤45. The effective magnetic anisotropy K e was measured by applying the law of approach to saturation. The value of K e decreases with an increase of Ni content. It is noticed that the strain anisotropy makes a large contribution to the magnetic anisotropy. The estimation of grain size leads to the determination of the single domain critical size and domain wall energy. The exchange stiffness and exchange integral deduced from the relationship between the effective magnetic anisotropy and domain wall energy are in agreement with that calculated by other methods.展开更多
The positioning of anti-monopoly law depends on its unique value,goal and function.From the beginning,anti-monopoly law has had a great political and economic mission,and can become a“super law”with a grand value go...The positioning of anti-monopoly law depends on its unique value,goal and function.From the beginning,anti-monopoly law has had a great political and economic mission,and can become a“super law”with a grand value goal and a powerful function in economic adjustment.The uniqueness of the Internet,in capital,technology and business models,easily allows Internet platforms to grow anarchically,and to have a high correlation with anti-monopoly concerns.Internet anti-monopoly policy should first expand its thinking and elevate its stance in macro value,and seek appropriate legal and economic technical paths.China’s Internet platform anti-monopoly policy cannot simply follow today’s international and superficial trend,which does not contribute to positive experience and may conceal various interests.Instead,China’s Internet platform anti-monopoly policy should actively follow,respect and serve the substantial development interests of China’s digital economy,operating in a timely fashion and at the right location,in ways that are opportune,moderate and modest.It should always be committed to the innovation and development of China’s Internet industry and to international competitiveness.Internet anti-monopoly policy should adhere to the rule of law,build a corresponding rule system,ensure objectivity,neutrality and rationality,and prevent irrationality and over-excitement.展开更多
基金Supported by the National Natural Science Foundation of China(No.51275126)the China Aerospace Science and Technology CorporationHarbin Institute of Technology Joint Technical Innovation Center Fund Project(CASC-HIT15-1A04)
文摘Engine-variable pump-variable motor drive system is a complex nonlinear system. In order to improve system response speed and stability,a sliding-mode variable-structure control based on a feedback linearization theory is analyzed in this research. A standardized system model is established and linearized by the feedback linearization theory,and the input dimension is reduced through the relationship between variables which has simplified the linearization process. Then the sliding-mode controller using an exponential reaching law is designed and the Lyapunov stability of this algorithm is verified. The simulation results show that the sliding-mode variable-structure controller based on the feedback linearization theory can improve system response speed,reduce overshoot and achieve stronger robustness,so the vehicle speed control requirements can be satisfied well.
文摘Fe 100- x Ni x alloys of ultrafine particle with the average grain size of about 10 nm were synthesized by mechanically alloying process. The samples were investigated by X ray diffraction and measurements of the saturation magnetization and coercivity force. Both b.c.c and f.c.c phase exist within a wide range for Fe 100- x Ni x , while x ≤45. The effective magnetic anisotropy K e was measured by applying the law of approach to saturation. The value of K e decreases with an increase of Ni content. It is noticed that the strain anisotropy makes a large contribution to the magnetic anisotropy. The estimation of grain size leads to the determination of the single domain critical size and domain wall energy. The exchange stiffness and exchange integral deduced from the relationship between the effective magnetic anisotropy and domain wall energy are in agreement with that calculated by other methods.
基金This paper is a phased achievement of major projects of National Social Science Foundation“Research on Intellectual Property Governance System of Digital Cyberspace”(project number:19ZDA164).
文摘The positioning of anti-monopoly law depends on its unique value,goal and function.From the beginning,anti-monopoly law has had a great political and economic mission,and can become a“super law”with a grand value goal and a powerful function in economic adjustment.The uniqueness of the Internet,in capital,technology and business models,easily allows Internet platforms to grow anarchically,and to have a high correlation with anti-monopoly concerns.Internet anti-monopoly policy should first expand its thinking and elevate its stance in macro value,and seek appropriate legal and economic technical paths.China’s Internet platform anti-monopoly policy cannot simply follow today’s international and superficial trend,which does not contribute to positive experience and may conceal various interests.Instead,China’s Internet platform anti-monopoly policy should actively follow,respect and serve the substantial development interests of China’s digital economy,operating in a timely fashion and at the right location,in ways that are opportune,moderate and modest.It should always be committed to the innovation and development of China’s Internet industry and to international competitiveness.Internet anti-monopoly policy should adhere to the rule of law,build a corresponding rule system,ensure objectivity,neutrality and rationality,and prevent irrationality and over-excitement.
