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731.
Iqtadar Hussain Tariq Shah Muhammad Asif Gondal Hasan Mahmood 《Nonlinear dynamics》2013,74(1-2):271-275
The theory of chaos is applied to the construction of substitution boxes used in encryption applications. The synthesis process of the proposed substitution boxes is presented, which is based on chaotic Baker’s map and TDERC chaotic sequences. The objectives of the new substitution box are to provide enhanced resistance against differential and linear cryptanalysis. The constructed substitution boxes uses Galois field elements and relies on discrete chaotic maps while keeping differential and linear approximation probabilities to desired levels. 相似文献
732.
The steady two-dimensional mixed convection flow of a micropolar fluid over a non-linear stretching sheet is investigated. The governing non-linear equations and their associated boundary conditions are transformed into coupled non-linear ordinary differential equations. The series solution of the problem is obtained by utilizing the homotopy analysis method (HAM). The convergence of the obtained series solutions is carefully checked. The physical significance of interesting parameters on the flow and the thermal fields are shown through graphs and discussed in detail. The values of wall shear stress, couple wall stress and the local Nusselt number are tabulated. Comparison is also made with the corresponding results of viscous fluid with no mixed convection and an excellent agreement is noted. 相似文献
733.
D. N. Khan Marwat A. H. Kara T. Hayat 《International Journal of Theoretical Physics》2008,47(11):3075-3081
We show how one can construct conservation laws of the Liang equation which is not variational but may be regarded as Euler-Lagrange
in part. This first requires the determination of the Noether-type symmetries associated with the partial Lagrangian. The final construction
of the conservation laws resort to a formula equivalent to Noether’s theorem. A variety of subclasses are given and, for each,
a large number of conserved flows are found—the method is usable for any general choice of the variable speed of sound. 相似文献
734.
This article reports the homotopy solution for stagnation point flow of a non-Newtonian fluid.An incompressible second grade fluid impinges on the wall either orthogonally or obliquely.The resulting nonlinear problems have been solved by a homotopy analysis method(HAM).Convergence of the series solutions is checked.Such solutions are compared with the numerical solutions presented in a study [Int.J.Non-Linear Mech.43(2008) 941].Excellent agreement is noted between the numerical and series solutions. 相似文献
735.
Prasenjit Mondal Rajdeep Chowdhury Somen Nandi Md. Asif Amin Kankan Bhattacharyya Surajit Ghosh 《化学:亚洲杂志》2019,14(24):4616-4624
The dynamics of cell‐cell adhesion are complicated due to complexities in cellular interactions and intra‐membrane interactions. In the present work, we have reconstituted a liposome‐based model system to mimic the cell‐cell adhesion process. Our model liposome system consists of one fluorescein‐tagged and one TRITC (tetramethyl‐rhodamine isothiocyanate)‐tagged liposome, adhered through biotin‐neutravidin interaction. We monitored the adhesion process in liposomes using Förster Resonance Energy Transfer (FRET) between fluorescein (donor) and TRITC (acceptor). Occurrence of FRET is confirmed by the decrease in donor lifetime as well as distinct rise time of the acceptor fluorescence. Interestingly, the acceptor's emission exhibits fluctuations in the range of ≈3±1 s. This may be attributed to structural oscillations associated in two adhered liposomes arising from the flexible nature of biotin‐neutravidin interaction. We have compared the dynamics in a cell‐mimicking liposome system with that in an in vitro live cell system. In the adhered live cell system, we used CPM (7‐diethylamino‐3‐(4‐maleimido‐phenyl)‐4‐methylcoumarin, donor) and nile red (acceptor), which are known to stain the membrane of CHO (Chinese Hamster Ovary) cells. The dynamics of the adhered membranes of two live CHO cells were observed through FRET between CPM and nile red. The acceptor fluorescence intensity exhibits an oscillation in the time‐scale of ≈1±0.75 s, which is faster compared to the reconstituted liposome system, indicating the contributions and involvement of multiple dynamic protein complexes around the cell membrane. This study offers simple reconstituted model systems to understand the complex membrane dynamics using a FRET‐based physical chemistry approach. 相似文献
736.
Exact analytical solutions for magnetohydrodynamic (MHD) flows of an incompressible second grade fluid in a porous medium are developed. The modified Darcy's law for second grade fluid has been used in the flow modelling. The Hall effect is taken into account. The exact solutions for the unsteady flow induced by the time-dependent motion of a plane wall between two side walls perpendicular to the plane has been constructed by means of Fourier sine transforms. The similar solutions for a Newtonian fluid, performing the same motion, appear as limiting cases of the solutions obtained here. The influence of various parameters of interest on the velocity and shear stress at the bottom wall has been shown and discussed through several graphs. A comparison between a Newtonian and a second grade fluids is also made. 相似文献
737.
This study looks at the magnetohydrodynamic (MHD) flow of a generalized Burgers’ fluid between two heated disks rotating about
noncoaxial axes normal to the disks. The steady flow and heat transfer analysis is investigated by providing exact analytic
solutions. The effect of Hall current is taken into consideration. Calculations are carried out for velocity, temperature,
force, and torque exerted by the fluid on one of the disks. The physical interpretation for the emerging parameters is discussed
with the help of graphs. The results are compared with those available in the existing literature. 相似文献
738.
Sadki Hayat Bourass Mohamed Bennani Mohammed Naciri Bouachrine Mohammed 《Research on Chemical Intermediates》2018,44(10):6071-6085
Research on Chemical Intermediates - We used density functional theory at B3LYP level with 6-31G(d,p) basis set for all atoms to study the electrochemical, photovoltaic, and absorption properties... 相似文献
739.
740.
Nonlinear Dynamics - This paper presents the tracking behavior of fractional-order (FO) variants of the normalized least mean square (NLMS) algorithm in a nonstationary environment modeled as... 相似文献