In this paper, He's Frequency-Amplitude Formulation (HFAF) and He's Energy Balance Method (HEBM) are employed to solve the generalized Duffing equation in the form of over (x, ̈) + x + α3 x3 + α5 x5 + α7 x7 + ⋯ + αn xn = 0 . For any arbitrary power of n, a frequency analysis is carried out and the relationship between the natural frequency and the initial amplitude is obtained in analytical form...

New equations are proposed for frequency and amplitude of a ring oscillator. The method is general enough to be used for all types of delay stages. Using exact largesignal circuit analysis, closed form equations for estimating the frequency and amplitude of a high frequency ring oscillator are derived as an example. The method takes into account the effect of various parasitic capacitors to...

In this paper, the effects of plasma discharge parameters on the nano particles formation process in a plasma enhanced chemical vapor deposition (PECVD) reactor using a model based on equations of ionization kinetics for different active species are studied. A radio frequency applied electric field causes ionization inside the reactor and consequently different reaction schemically active speci...

The fatigue test of wind turbine blade is an important means to verify the life blade. This paper analyses problems existing in blade, focuses on excitation mode, relationship between amplitude and vibration frequency principle, puts forward feasible solutions practical operation.

Electrophysiological properties of lamprey spinal motoneurons were measured to determine whether their cellular properties change as the spinal cord goes from a quiescent state to the active state of fictive swimming. Intracellular microelectrode recordings of membrane potential were made from motoneurons in the isolated spinal cord preparation. Electrophysiological properties were first charac...

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in this paper, the nonlinear free vibrations of thin symmetric and non-symmetric cross-ply composite plates subjected to biaxial initial stresses are investigated. because of their excellent properties such as specific strength and specific stiffness, composite plates have wide applications in aerospace and mechanical structures. based on von-karman's strain-displacement relations and using gal...