The development of environmental information governance includes three phases: providing for oneself,information disclosure,and public service. And then China is in the transition and transformation of environmental i...The development of environmental information governance includes three phases: providing for oneself,information disclosure,and public service. And then China is in the transition and transformation of environmental information disclosure to the environmental information public service. The core of the transformation is public participation,in the whole procedure of environmental information supply decision making,production,and quality supervision and evaluation,etc. The target path of the environmental information governance reform includes five parts: improvement of public satisfaction,optimizing information disclosure,information quality control,integration of information resources,and multiple supply.展开更多
The chaotic motion of an elastic shaft-disk rotor system including thegeometric nonlinearity of the shaft with a transverse crack is investigated. The critical conditionfor the system to enter chaotic state is given b...The chaotic motion of an elastic shaft-disk rotor system including thegeometric nonlinearity of the shaft with a transverse crack is investigated. The critical conditionfor the system to enter chaotic state is given by the Melnikov method. Meanwhile, whether the chaosoccurs is determined by the Poincare map, phase portrait and time-displacement history diagram.展开更多
The problem of beam-plates with a delamination located at anarbitrary site undergoing non- linear free vibration without damp isinvestigated. For this problem, nonlinear governing equations as wellas the continuity, e...The problem of beam-plates with a delamination located at anarbitrary site undergoing non- linear free vibration without damp isinvestigated. For this problem, nonlinear governing equations as wellas the continuity, equilibrium and compatibility conditions areestablished. The Galerkin method and harmonic balance method areemployed to find solutions. Finally, in some examples,amplitude-frequency curves of the delaminated structure are presentedin order to reveal some special dynamic features.展开更多
文摘The development of environmental information governance includes three phases: providing for oneself,information disclosure,and public service. And then China is in the transition and transformation of environmental information disclosure to the environmental information public service. The core of the transformation is public participation,in the whole procedure of environmental information supply decision making,production,and quality supervision and evaluation,etc. The target path of the environmental information governance reform includes five parts: improvement of public satisfaction,optimizing information disclosure,information quality control,integration of information resources,and multiple supply.
文摘The chaotic motion of an elastic shaft-disk rotor system including thegeometric nonlinearity of the shaft with a transverse crack is investigated. The critical conditionfor the system to enter chaotic state is given by the Melnikov method. Meanwhile, whether the chaosoccurs is determined by the Poincare map, phase portrait and time-displacement history diagram.
基金the National Natural Science Foundation of China( No.19872024).
文摘The problem of beam-plates with a delamination located at anarbitrary site undergoing non- linear free vibration without damp isinvestigated. For this problem, nonlinear governing equations as wellas the continuity, equilibrium and compatibility conditions areestablished. The Galerkin method and harmonic balance method areemployed to find solutions. Finally, in some examples,amplitude-frequency curves of the delaminated structure are presentedin order to reveal some special dynamic features.