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81.
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
82.
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
83.
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
84.
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
85.
86.
Zaki Nadia G. Mahmoud Walaa H. El Kerdawy Ahmed M. Abdallah Abanoub Mosaad Mohamed Gehad G. 《Research on Chemical Intermediates》2020,46(6):3193-3216
Research on Chemical Intermediates - Reaction of cocaine (Cn) with Ln(III) chloride salts [where Ln?=?La(III), Er(III), and Yb(III)] afforded complexes of the [Ln(Cn)Cl(OH2)3].2Cl type... 相似文献
87.
Elhelw Mohamed El-Maghlany Wael M. 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2563-2573
Journal of Thermal Analysis and Calorimetry - An evaluation of using a thermal storage system utilized with air conditioning cycle in Egypt is the main aim of this paper. This study includes the... 相似文献
88.
Journal of Solid State Electrochemistry - Remarkable selective analysis of biomolecules i.e., glucose and ascorbic acid on copper oxide facets was reported for the first time. The copper oxide... 相似文献
89.
Jules K. Djoko Virginie S. Konlack Mohamed Mbehou 《Numerical Methods for Partial Differential Equations》2020,36(1):86-117
In this work, we consider the heat equation coupled with Stokes equations under threshold type boundary condition. The conditions for existence and uniqueness of the weak solution are made clear. Next we formulate the finite element problem, recall the conditions of its solvability, and study its convergence by making use of Babuska–Brezzi's conditions for mixed problems. Third we formulate an Uzawa's type iterative algorithm that separates the fluid from heat conduction, study its feasibility, and convergence. Finally the theoretical findings are validated by numerical simulations. 相似文献
90.
Chaabane Ikram Guermazi Radhouane Hammami Mohamed 《Advances in Data Analysis and Classification》2020,14(3):677-745
Advances in Data Analysis and Classification - Several machine learning techniques assume that the number of objects in considered classes is approximately similar. Nevertheless, in real-world... 相似文献