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81.
Mohamed Kameche Mohamed Feham 《International Journal of Infrared and Millimeter Waves》2006,27(5):687-705
Simple techniques for determining the broadband small signal equivalent circuit (SSEC) of MESFETs are presented in this paper.
The intrinsic elements are calculated using two-dimensional method from the Y parameters, which are obtained from the Fourier
analysis of the device transient response to voltage-step perturbations at the drain and gate electrodes. Whereas, the parasitic
external elements are determined by simple approximations used in transmission line modeling. In addition, a new technique
is also proposed to determine the source and drain series resistances. A comparison of the SSEC of three different MESFETs
technologies shows that the MESFETs on GaN and 4H-SiC are suitable for high power applications. The method used to determine
the intrinsic elements is validated with simulated data obtained by Monte Carlo method. 相似文献
82.
83.
Elferjani Atef Garcia-Granda Santiago Dammak Mohamed 《Research on Chemical Intermediates》2019,45(3):1357-1379
Research on Chemical Intermediates - A new compound thallium ammonium sulfate selenate tellurate: Tl0.92(NH4)0.08(SO4)0.65(SeO4)0.35Te(OH)6 (TlNSSeTe) has been synthesized by slow evaporation at... 相似文献
84.
85.
Omar Abo-Bakr Omar Abdel-Rahman Mohamed A. E. El-Mongy Sayed A. 《Physics of Particles and Nuclei Letters》2019,16(6):835-841
Physics of Particles and Nuclei Letters - The natural radioactivity measurements and analysis of 232Th have been studied using γ-ray spectroscopy depending on its decay daughters in... 相似文献
86.
Ilyas Saad Alfosail Feras K. Bellaredj Mohamed L. F. Younis Mohammad I. 《Nonlinear dynamics》2019,95(3):2263-2274
Nonlinear Dynamics - We present an investigation of the dynamic behavior of an electrostatically actuated clamped–clamped microbeam, under the simultaneous excitation of primary and... 相似文献
87.
Oussama Graja Bacem Zghal Kajetan Dziedziech Fakher Chaari Adam Jablonski Tomasz Barszcz Mohamed Haddar 《Comptes Rendus Mecanique》2019,347(1):49-61
Planetary gearboxes are widely used in industrial machines. They usually work in harsh environments giving rise to damages and high maintenance costs. Condition monitoring is a key action allowing one to detect the presence of such damage ensuring healthy running conditions. The knowledge of the dynamic behavior of such a gearbox can be achieved using modeling tools as a primary step before conditioning the monitoring subject. In addition, modeling a gear set can help in the stage of design in order to optimize physical and geometric parameters of the system. Therefore, in this work, a two-dimensional lumped parameter model is adopted to build all vibration sources. The time-varying mesh stiffness is approximated as a square wave form. A novel mathematical formulation is proposed to model the amplitude modulation phenomenon due to the rotational motion of the planets around the center of the gearbox. Finally, the overall vibration signal is concluded as a summation of all vibration components influenced by the modulation function. 相似文献
88.
International Journal of Theoretical Physics - We consider a dissipative system of two qubits interacting with a cavity field through the degenerate 2-photon transitions. The cavity is initially... 相似文献
89.
Mourad Kainane Mezadek Mohamed Kainane Mezadek Michael Reissig 《Mathematical Methods in the Applied Sciences》2020,43(6):3117-3147
In this paper, we study the global (in time) existence of small data solutions to the Cauchy problem for the semilinear wave equation with friction, viscoelastic damping, and a power nonlinearity. We are interested in the connection between regularity assumptions for the data and the admissible range of exponents p in the power nonlinearity. 相似文献
90.
Ghommem Mehdi Najar Fehmi Arabi Mohamed Abdel-Rahman Eihab Yavuz Mustafa 《Nonlinear dynamics》2020,101(1):271-291
Nonlinear Dynamics - We present a unified model of electrostatic sensors comprising cantilever microbeam resonators in fluid media. The model couples Euler–Bernoulli beam equation to the... 相似文献