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21.
After being introduced by Shannon as a measure of disorder and unavailable information, the notion of entropy has found its applications in a broad range of scientific disciplines. In this paper, we present a systematic review on the applications of entropy and related information-theoretical concepts in the design, implementation and evaluation of cryptographic schemes, algorithms, devices and systems. Moreover, we study existing trends, and establish a roadmap for future research in these areas. 相似文献
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23.
Behrouz Tabarrok Bruce H. Karnopp 《Zeitschrift für Angewandte Mathematik und Physik (ZAMP)》1967,18(4):580-587
Zusammenfassung Die Schwingungen des Timoshenko-Trägers werden mit Hilfe sich ergänzender Variationsprinzipien analysiert. Es werden Rayleigh-Quotienten, die auf den beiden Prinzipien basieren, für die Eigenfrequenzen angegeben. Sodann werden duale Träger mit konstanten Querschnittpaaren definiert und die Beziehungen zwischen den Eigenfrequenzen und Schwingungsformen der dualen Träger diskutiert. 相似文献
24.
Milani Saeideh Ghaemimanesh Fatemeh Salimi Ali Hadavi Reza Bayat Ali Ahmad Alirezapour Behrouz Rabbani Hodjattallah 《Journal of Radioanalytical and Nuclear Chemistry》2018,316(1):267-273
Journal of Radioanalytical and Nuclear Chemistry - Receptor tyrosine kinase Ror1 is widely expressed during embryogenesis but it is absent within most mature tissues. However, expression of Ror1... 相似文献
25.
KF‐Melamine formaldehyde resin (KF‐MFR) was demonstrated to be a highly efficient heterogenious catalyst for cross‐aldol condensation under microwave irradiation. In this synthesis, various aldehydes and ketones were condensed together in the presence of supported KF on melamine‐formaldehyde resin to afford different chalcone derivatives in good to excellent yields. KF‐MFR proved to have unique termal and chemical resistance and can be reused for many consecutive runs without remarkable loss in catalytic activity. 相似文献
26.
A new fused heterocyclic derivatives of pyrrole containing acetonitrile or cyanoacetonitrile moiety at 3-position is described by a one-pot multicomponent reaction. The reaction of dimedone, various aniline, aryl glyoxal with malononitrile/ethyl cyanoacetate/methyl cyanoacetate under mild conditions. The present method does not involve any hazardous organic solvents or catalysts. The significant features of this method are readily available starting materials, good yields, and easy purification. 相似文献
27.
In this study,by means of homotopy perturbation method(HPM) an approximate solution of the magnetohydrodynamic(MHD) boundary layer flow is obtained.The main feature of the HPM is that it deforms a difficult problem into a set of problems which are easier to solve.HPM produces analytical expressions for the solution to nonlinear differential equations.The obtained analytic solution is in the form of an infinite power series.In this work,the analytical solution obtained by using only two terms from HPM soluti... 相似文献
28.
Behrouz Kheirfam 《Journal of Optimization Theory and Applications》2014,161(3):853-869
In this paper, we first present a full-Newton step feasible interior-point algorithm for solving horizontal linear complementarity problems. We prove that the full-Newton step to the central path is quadratically convergent. Then, we generalize an infeasible interior-point method for linear optimization to horizontal linear complementarity problems based on new search directions. This algorithm starts from strictly feasible iterates on the central path of a perturbed problem that is produced by a suitable perturbation in the horizontal linear complementarity problem. We use the so-called feasibility steps that find strictly feasible iterates for the next perturbed problem. By using centering steps for the new perturbed problem, we obtain a strictly feasible iterate close enough to the central path of the new perturbed problem. The complexity of the algorithm coincides with the best known iteration bound for infeasible interior-point methods. 相似文献
29.
This work is an investigation on the roots of chaotic attitudinal motion in a class of asymmetrical gyrostat satellites. The result shows that for a class of Kelvin type gyrostat satellite, there is an equivalent rigid spinning satellite with the same attitude dynamics. Finding some constants of motion and eliminating the cyclic coordinates, the rotational kinetic energy is changed to a quadratic form and using Jordan canonical form of the associated inertia tensor and transforming the coordinate system, the Hamiltonian has been changed to those of a rigid satellite. The Hamiltonian has been split into integrable and non-integrable parts. Using Deprit canonical transformation and Andoyer variables the integrable part has been reduced to a one-dimensional form. The reduced Hamiltonian shows that the regular dynamics of the satellite can be chaotic, under the influence of gravitational effects. To demonstrate various attitudinal dynamics of the satellite, a second-order Poincaré map is employed. This research shows firstly, that the attitudinal dynamics of Kelvin type gyrostat satellites and rigid satellites follow the same dynamical patterns, secondly, for non-linear analysis of dynamics of gyrostat satellite based on the perturbation methods, there is a preferable form for Hamiltonian of the system in the near-integrable fashion and thirdly the chaotic motion is originated from the gravitational field effects that can be suppressed by increasing the attitudinal energy of the satellite in comparison with the translational energy. 相似文献
30.
Copper/Graphene/Clay Nanohybrid: A Highly Efficient Heterogeneous Nanocatalyst for the Synthesis of Novel 1,2,3‐Triazolyl Carboacyclic Nucleosides via ‘Click’ Huisgen 1,3‐Dipolar Cycloaddition 下载免费PDF全文
Mohammad Navid Soltani Rad Somayeh Behrouz S. Jafar Hoseini Hasan Nasrabadi Maryam Saberi Zare 《Helvetica chimica acta》2015,98(9):1210-1224
A very mild and highly efficient synthesis of some novel 1H‐1,2,3‐triazolyl carboacyclic nucleosides via a ‘Click’ Huisgen cycloaddition of N‐propargyl nucleobases and azido alcohols using Cu/aminoclay/reduced graphene oxide nanohybrid (Cu/AC/r‐GO nanohybrid) as nanocatalyst is described. The preparation and characterization of Cu/AC/r‐GO nanohybrid are discussed. This catalyst was characterized by X‐ray diffraction, FT‐IR, TEM, and energy‐dispersive analysis of X‐ray techniques. Cu/AC/r‐GO nanohybrid is a stable and highly efficient heterogeneous nanocatalyst that can be easily prepared, used, and restored from the reaction mixture by simple filtration, and reused for many consecutive trials without significant decrease in activity. 相似文献