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81.
Nonlinear measure approach for the robust exponential stability analysis of interval inertial Cohen–Grossberg neural networks 下载免费PDF全文
Ruoxia Li Jinde Cao Ahmed Alsaedi Bashir Ahmad Fuad E Alsaadi Tasawar Hayat 《Complexity》2016,21(Z2):459-469
This article is concerned with the existence and robust stability of an equilibrium point that related to interval inertial Cohen–Grossberg neural networks. Such condition requires the existence of an equilibrium point to a given system, so the existence and uniqueness of the equilibrium point are emerged via nonlinear measure method. Furthermore, with the help of Halanay inequality lemma, differential mean value theorem as well as inequality technique, several sufficient criteria are derived to ascertain the robust stability of the equilibrium point for the addressed system. The results obtained in this article will be shown to be new and they can be considered alternative results to previously results. Finally, the effectiveness and computational issues of the two models for the analysis are discussed by two examples. © 2016 Wiley Periodicals, Inc. Complexity 21: 459–469, 2016 相似文献
82.
In this article, a simplified bidirectional associative memory network with delays involving six neurons is considered. By analyzing the distribution of roots of the characteristic equation for linearized system regarding the sum of delay as a bifurcation parameter, we obtain the condition of the occurrence for Hopf bifurcation. It reveals that Hopf bifurcation occurs when the sum of the delay passes through a critical value. The direction and the stability of the bifurcating periodic solution are determined by applying the normal form theory and center manifold theorem. Finally, a numerical example is used to illustrate the validity of theoretical results obtained. © 2015 Wiley Periodicals, Inc. Complexity 21: 9–28, 2016 相似文献
83.
A. Alsaedi T. Hayat T. Muhammad S. A. Shehzad 《Computational Mathematics and Mathematical Physics》2016,56(9):1665-1678
This study models the magnetohydrodynamic (MHD) three-dimensional boundary layer flow of viscoelastic fluid. The flow is due to the exponentially stretching surface. The heat transfer analysis is performed through prescribed surface temperature (PST) and prescribed surface heat flux (PHF). The thermal conductivity is taken temperature dependent. Series solutions of velocities and temperatures are constructed. Graphical results for PST and PHF cases are plotted and analyzed. Numerical values of skin-friction coefficients and Nusselt numbers are presented and discussed. 相似文献
84.
Tasawar Hayat S. Asghar B. Asghar 《International Journal of Infrared and Millimeter Waves》1999,20(6):1169-1194
The spherical wave scattering response by a perfectly conducting open–ended waveguide in a biisotropic medium is obtained. Interestingly, the vector diffraction problem is reduced to the scattering of a single scalar field, this scalar field being the normal component of either a left–handed or a right–handed Beltrami field. Here, we explicitly consider the scattering of the left–handed field component, that of the other scalar field being analogously tractable. The solution is constructed with the aid of the Wiener–Hopf technique. 相似文献
85.
Rabia Djellouli Chokri Bekkey Abdelaziz Choutri Hayat Rezgui 《Mathematical Methods in the Applied Sciences》2000,23(17):1551-1583
An efficient method coupling a local boundary condition to a finite element technique is proposed to compute guided modes of optical fibres under the weak guidance assumptions. This method is designed to provide accurate solutions for optical fibres with no restriction on their shape as well as on their refractive index profile. Several numerical experiments are performed to demonstrate this point. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献
86.
Natarajan Arumugam Abdulrahman I. Almansour Raju Suresh Kumar Mohammad Altaf S.M. Mahalingam Govindasami Periyasami J. Carlos Menéndez Abdul Jaleel Mohammad Ali Al-Aizari 《Tetrahedron letters》2019,60(8):602-605
A series of structurally intriguing novel pyrrolo[3,2-c]quinolinone heterocyclic hybrids have been synthesized for the first time via a one-pot multicomponent domino reaction sequence that involves a 1,3-dipolar cycloaddition and two subsequent annulation steps. Baylis-Hillman adducts derived from various substituted benzaldehyde and methyl acrylate in presence of DABCO were used as a dipolarophiles, while the 1,3-dipole components were azomethine ylides, formed in situ from isatin derivatives and l-phenylalanine. The reaction generated five new bonds, three new rings and four contiguous stereocenters, which were created with full diastereomeric control. 相似文献
87.
This article studies the three-dimensional boundary layer flow of an elasticoviscous fluid over a stretching surface. Velocity
of the stretching sheet is assumed to be time-dependent. Effect of mass transfer with higher order chemical reaction is further
considered. Computations are made by the homptopy analysis method (HAM). Convergence of the obtained series solutions is explicitly
analyzed. Variations of embedding parameters on the velocity and concentration are graphically discussed. Numerical computations
of surface mass transfer are reported. Comparison of the present results with the numerical solutions is also given. 相似文献
88.
One-pot synthesis of pyrano[2,3-c]pyrazole derivatives via two or multicomponent condensation of β-ketoesters, hydrazine monohydrate/phenyl hydrazine, malononitrile, and substituted benzaldehydes is of great interest not only in synthetic chemistry but also in medicinal chemistry because of the tremendous biological activities, such as anticancer, anti-inflammatory, analgesic, antimicrobial, and enzyme inhibitory activities exhibited by pyranopyrazoles. This review provides extensive knowledge on novel synthetic methodologies of biologically active non-spiro/spiro-pyrano[2,3-c]pyrazole derivatives published recently. 相似文献
89.
Khalid Mohammed Khan Ghulam Murtaza MaharviSafdar Hayat Zia-UllahM. Iqbal Choudhary Atta-ur-Rahman 《Tetrahedron》2003,59(29):5549-5554
Treatment of aromatic carboxylic acids and substituted toluenes with a mixture of sodium bromate and sodium hydrogen sulfite in a two-phase system gave the corresponding esters in good yield. The intermediate α-brominated toluene was formed by the in situ generated hypobromous acid. The α-bromotoluene underwent an intermolecular nucleophilic substitution reaction with aromatic carboxylic acids present in the reaction mixture to afford the corresponding esters. 相似文献
90.
Computational studies on optoelectronic and charge transfer properties of some perylene‐based donor‐π‐acceptor systems for dye sensitized solar cell applications 下载免费PDF全文
Taniya Manzoor Summera Asmi Saba Niaz Altaf Hussain Pandith 《International journal of quantum chemistry》2017,117(5)
We report DFT studies on some perylene‐based dyes for their electron transfer properties in solar cell applications. The study involves modeling of different donor‐π‐acceptor type sensitizers, with perylene as the donor, furan/pyrrole/thiophene as the π‐bridge and cyanoacrylic group as the acceptor. The effect of different π‐bridges and various substituents on the perylene donor was evaluated in terms of opto‐electronic and photovoltaic parameters such as HOMO‐LUMO energy gap, λmax, light harvesting efficiency(LHE), electron injection efficiency (Øinject), excited state dye potential (Edye*), reorganization energy(λ), and free energy of dye regeneration (). The effect of various substituents on the dye–I2 interaction and hence recombination process was also evaluated. We found that the furan‐based dimethylamine derivative exhibits a better balance of the various optical and photovoltaic properties. Finally, we evaluated the overall opto‐electronic and transport parameters of the TiO2‐dye assembly after anchoring the dyes on the model TiO2 cluster assembly. 相似文献