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1.
Wei Yuting Wang Qihua Liu Wei 《Annals of the Institute of Statistical Mathematics》2021,73(3):535-553
Annals of the Institute of Statistical Mathematics - In this paper, a model averaging approach is developed for the linear regression models with response missing at random. It is shown that the... 相似文献
2.
Acta Mathematicae Applicatae Sinica, English Series - So far there have been few results presented on the exponential stability for time-changed stochastic differential equations. The main aim of... 相似文献
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Numerical Algorithms - In this paper, we study a fast linearized numerical method for solving nonlinear time-fractional diffusion equations. A new weighted method is proposed to construct... 相似文献
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Stochastic resonance (SR) has been extensively utilized in the field of weak fault signal detection for its characteristic of enhancing weak signals by transferring the noise energy. Aiming at solving the output saturation problem of the classical bistable stochastic resonance (CBSR) system, a double Gaussian potential stochastic resonance (DGSR) system is proposed. Moreover, the output signal-to-noise ratio (SNR) of the DGSR method is derived based on the adiabatic approximation theory to analyze the effect of system parameters on the DGSR method. At the same time, for the purpose of overcoming the drawback that the traditional SNR index needs to know the fault characteristic frequency (FCF), the weighted local signal-to-noise ratio (WLSNR) index is constructed. The DGSR with WLSNR can obtain optimal parameters adaptively, thereby establishing the DGSR system. Ultimately, a DGSR method is proposed and applied in centrifugal fan blade crack detection. Through simulations and experiments, the effectiveness and superiority of the DGSR method are verified. 相似文献
6.
Nonlinear Dynamics - This paper proposes an output feedback control strategy to achieve the global regulation of a class of large-scale feedforward nonlinear systems with discrete and distributed... 相似文献
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Numerical Algorithms - The original solutions of highly oscillatory integral equations usually have rapid oscillation, which means that conventional numerical approaches used to solve these... 相似文献
8.
Second harmonic generation (SHG) using intense Hermite-Gaussian laser beam (HGLB) propagating through the plasma for mode-indices m = 0 and m = 1 is reported in the present work. Ponderomotive force induced density perturbation beats with the oscillatory velocity of electrons at incident laser frequency, generate the second harmonic nonlinear current that give rise to SHG. Using paraxial approximations, we have derived the coupled equations for the beam width parameter of HGLB and second harmonic's normalized amplitude. Resonance condition is obtained by considering wiggler magnetic field which providing an extra momentum to the second harmonic photon and this result a significant increase in the amplitude of SHG. Our analysis shows the prominent rise in normalized amplitude of second harmonic on increasing the value of the intensity of fundamental laser pulse, normalized wiggler magnetic field and normalized density of plasma. It is notified that the gain of SHG is more prominent for m = 1. Dependency of laser and plasma parameters on SHG is also reported in the current work. 相似文献
9.
The first aim of this paper is to investigate the growth of the entire function defined by the Laplace-Stieltjes transform converges on the whole complex plane.By introducing the concept of generalized order,we obtain two equivalence theorems of Laplace-Stiettjes transforms related to the generalized order,An*andλn.The second purpose of this paper is to study the problem on the approximation of this Laplace-Stieltjes transform.We also obtain some theorems about the generalized order,the error,and the coefficients of Laplace-Stieltjes transforms,which are generalization and improvement of the previous results. 相似文献
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