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101.
Sliding observer for synchronization of fractional order chaotic systems with mismatched parameter 总被引:1,自引:0,他引:1
Hadi Delavari Danial M. Senejohnny Dumitru Baleanu 《Central European Journal of Physics》2012,10(5):1095-1101
In this paper, we propose an observer-based fractional order chaotic synchronization scheme. Our method concerns fractional order chaotic systems in Brunovsky canonical form. Using sliding mode theory, we achieve synchronization of fractional order response with fractional order drive system using a classical Lyapunov function, and also by fractional order differentiation and integration, i.e. differintegration formulas, state synchronization proved to be established in a finite time. To demonstrate the efficiency of the proposed scheme, fractional order version of a well-known chaotic system; Arnodo-Coullet system is considered as illustrative examples. 相似文献
102.
A growing interest exists currently in the analysis of time series by the complex network theory. Here we present a simple and quick way for mapping time series to complex networks. Using a simple rule allows us to transform time series into a textual sequence then we divide it into words with fixed size. Distinct words are nodes of the network, and we have complete control on the network scale by adjusting the word size. Two nodes are linked if their associated words co-occur in sequence. We show that the network topological measures quantify the persistence and the long range correlations in fractional Brownian processes. For a particular word size we assume some relations between the topological measures and the Hurst exponent which characterised the persistence in fractional Brownian processes. 相似文献
103.
The hub location problem finds the location of hubs and allocates the other nodes to them. It is widely supposed the network created with the hub nodes is complete in the extensive literature. Relaxation of this basic supposition forms the present work. The model minimizes the cost of the proprietor, including the fixed costs of hubs, hub links and spoke links. Costs of hub and spoke links are contemplated as fixed cost or maintenance cost. Moreover, the model considers routing costs of customers who want to travel from origins to destinations. In this study, we offer a model to the multiple allocations of the hub location problems, under the incomplete hub location-routing network design. This model is easily transformed to other hub location problems using one or more constraints. No network format is dictated on the hub network. We suggest a set of valid inequalities for the formulation. Some lower bounds are developed using a Lagrangian relaxation approach and the valid inequalities. Computational analyses evaluate the performances of the lower bounding implementations and valid inequalities. Furthermore, we explore the effects of several factors on the design and solution time of the problem formulation. 相似文献
104.
Brendan Goldsmith Fatemeh Karimi Ahad Mehdizadeh Aghdam 《Czechoslovak Mathematical Journal》2013,63(3):819-831
In this paper we investigate two new classes of torsion-free Abelian groups which arise in a natural way from the notion of a torsion-free Crawley group. A group G is said to be an Erd?s group if for any pair of isomorphic pure subgroups H,K with G/H ? G/K, there is an automorphism of G mapping H onto K; it is said to be a weak Crawley group if for any pair H,K of isomorphic dense maximal pure subgroups, there is an automorphism mapping H onto K. We show that these classes are extensive and pay attention to the relationship of the Baer-Specker group to these classes. In particular, we show that the class of Crawley groups is strictly contained in the class of weak Crawley groups and that the class of Erd?s groups is strictly contained in the class of weak Crawley groups. 相似文献
105.
A Si(111) surface has been derivatized with a thiophene-terminated alkyl monolayer which was subsequently photoanodically oxidized in the presence of thiophene to yield a strongly adherent and smooth conducting film. 相似文献
106.
107.
In our previous paper, we extended the Tao and Mason equation of state (TM EOS) to refrigerant fluids, using the speed of sound data. Here, we predict the equation of state for ionic liquids (ILs). The considered ILs are [Bmim][PF6], [C2mim][NtF2], [C3mim][NtF2], [C6mim][NtF2], [C7mim][NtF2], [C2mim][EtOSO3], [Bmim][MeSO4], [Bmim][OcSO4], and [C4mim][dca]. The equation of state consists of three temperature-dependent parameters: the second virial coefficient, a constant for scaling the softness of repulsive force, and an effective hard-sphere diameter equivalent to the van der Waals co-volume. The second virial coefficients of ILs are scare and there is no accurate potential energy function to allow their theoretical calculation. In this work, the second virial coefficient have been calculated using corresponding states correlation based on temperature and density at normal boiling point. The other two parameters of the equation of state can be calculated using a scaling rule. Analysis of our predicted results shows that the Tao?CMason equation of state is capable of accurately predicting the density of ILs at any temperature and pressure. The overall average absolute deviation densities for 1,633 data points are 2.05%. Also, the density of ILs obtained from the TM EOS has been compared with those calculated from vdW?CCS?C?? and Peng?CRobinson (PR) equation of state. Our results are in favor of the preference of the TM EOS over the two other equations of state. The overall average absolute deviation for 1,633 data points calculated by vdW?CCS?C?? and PR equation of state are 6.63% and 12.19%, respectively. 相似文献
108.
Abdollah Salimi Roaya Zand‐Karimi Abdollah Noorbakhash Saied Soltanian 《Electroanalysis》2010,22(20):2434-2442
For the first time silicon nitride (Si3N4) nanoparticles was used for preparation electrochemical biosensor. GOx immobilized on the Si3N4 nanoparticles exhibits facile and direct electrochemistry. The surface coverage and heterogeneous electron transfer rate constant (ks) of immobilized GOx were 6.3×10?13 mol cm?2 and 47.4±0.3 s?1. The sensitivity, linear concentration range and detection limit of the biosensor for glucose detection were 38.57 µA mM?1 cm?2, 25 µM to 8 mM and 6.5 µM, respectively. This biosensor also exhibits good stability, reproducibility and long life time. These indicate Si3N4 nanoparticles is good candidate material for construction of third generation biosensor and bioelectronics devices. 相似文献
109.
Masoud Bodaghi Hesam Zolfonoon Mohammadreza Tahriri Meysam Karimi 《Solid State Sciences》2009,11(2):496-500
In this present work, the synthesis of nanocrystalline α-Al2O3 using pure aluminum (Al) and Fe2O3 (hematite) as the precursors by mechanical alloying technique has been studied. The formation of α-Al2O3 nanocrystallites occurs during the solid-state reaction and through the reduction treatment. Also in this paper, effects of milling time on particle size and the lattice strain nanocrystalline α-Al2O3 have been investigated. Obtained powders were evaluated by scanning electron microscopy (SEM), transmission electron microscopy (TEM), differential thermal analysis (DTA), thermal gravimetric analysis (TGA) and X-ray diffraction (XRD). The obtained results indicated that a reduction reaction was completed after 2 h milling in a planetary mill. The crystallite size of obtained α-alumina (α-Al2O3) was in general about 12 nm. Finally, the results showed appropriate homogeneity and dispersion of related nanocrystalline. 相似文献
110.
[reaction: see text] A new concept of simultaneous covalent anchoring of a N-heterocyclic carbene palladium/ionic liquid matrix on the silica surface and the application of the resulting catalyst in the Heck reaction of a variety of different haloarenes is described. The catalyst shows high thermal stability (up to 280 degrees C) and could be recovered and reused for four reaction cycles, giving a total TON congruent with 36 600. Furthermore, TEM coupled with EDX analysis indicate the formation of Pd nanoparticles within the immobilized IL layer. 相似文献