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881.
Sabir Jacquir Stéphane Binczak Jean-Marie Bilbault Viktor Kazantsev Vladimir Nekorkin 《Nonlinear dynamics》2006,44(1-4):29-36
An electrical circuit is proposed to realize an unidirectional coupling between two cells, mimicking chemical synaptic coupling.
Each cell represents the FitzHugh–Nagumo (FHN) model of neuron with a modified exitability (MFHN). We present experimental
results on frequency doublings and on the chaotic dynamics depending on the coupling strength in a master–slave configuration.
In all experiments, we stress the influence of the coupling strength on the control of the slave neuron. 相似文献
882.
883.
In this work we define and study quasi-contraction on a cone metric space. For such a mapping we prove a fixed point theorem. Among other things, we generalize a recent result of H. L. Guang and Z. Xian, and the main result of ?iri? is also recovered. 相似文献
884.
Lyudmila I. Larina Vladimir G. Rozinov Mikhail Yu. Dmitrichenko Lyudmila A. Es'kova 《Magnetic resonance in chemistry : MRC》2009,47(2):149-157
The structure of novel phosphorus‐containing N‐vinylazoles prepared by action of phosphorus pentachloride has been studied by multinuclear 1H, 13C, 15N, 31P and two‐dimensional (2D) NMR spectroscopy. N‐vinyl‐substituted 1,2‐diazoles and 1,2,3‐triazoles have undergone phosphorylation, exclusively, on double bond. N‐vinylazoles‐based hexa‐coordinated phosphorus compounds have been synthesized for the first time. 31P NMR spectroscopy provides the most convenient and unambiguous method for the investigation of E—Z‐isomeric structures of phosphorylated enamines. Copyright © 2008 John Wiley & Sons, Ltd. 相似文献
885.
Boris Arkhipov Vladimir Koterov Viacheslav Solbakov Dmitry Shapochkin Yulia Yurezanskaya 《Studies in Applied Mathematics》2008,120(1):87-104
We consider two applications of the stochastic discrete particles method. The first one is concerned with the dispersion of a passive pollutant by a turbulent stream with a scale dependent diffusion coefficient. The second application deals with the problem of an oil spill spreading on the water surface described by transport–diffusion equation with a nonlinear diffusion coefficient. For the first problem we develop a discrete particles algorithm provided the diffusion coefficient obeys Richardson's "4/3" law and show good correspondence with the numerical and analytical results. The second problem is more involved and we develop a heuristic procedure based on the standard discrete particles random walk algorithm updating the dependence of each particle step variance on the dependent function. The obtained solution coincides well with analytical and direct one-dimensional finite-difference solutions both for instantaneous and continuous oil release. 相似文献
886.
Vladimir Pestov 《Topology and its Applications》1998,90(1-3):223-225
Answering a question first explicitly stated by de Vries in 1993, we observe that for an arbitrary topological dynamical system the property of being an almost periodic point does not depend on the topology of the acting group. In other words, the traditional distinction made between the notions of an almost periodic point and of a discretely almost periodic point is unnecessary. 相似文献
887.
Amar Nath Vladimir Chechersky Robert Butterick Jr.III Steve Preite 《Solid State Communications》2006,138(5):224-228
The magnetic behavior of the Sr0.3 manganite is studied using a local microprobe, 57Co. In contrast with Ca substituted manganites, a much larger fraction of the material exhibits short-range order with superparamagnetic-like behavior even at 80 K. The differences in behavior are attributed to the large mismatch between the ionic radii of La+3 and the divalent substituent Sr+2, which introduces anharmonicity in local vibrations. In common with all other compounds exhibiting negative bulk magnetoresistivity, the Sr0.3 compound also exhibits very marked softening of lattice as one approaches Tc from below. Application of an external magnetic field results in coalescing of nanosized magnetic clusters to form larger ones with better alignment of spins. 相似文献
888.
889.
The energy of graphs and matrices 总被引:1,自引:0,他引:1
Vladimir Nikiforov 《Journal of Mathematical Analysis and Applications》2007,326(2):1472-1475
890.
Vladimir Samodivkin 《Mathematica Slovaca》2007,57(5):401-406
The k-restricted domination number of a graph G is the minimum number d
k
such that for any subset U of k vertices of G, there is a dominating set in G including U and having at most d
k
vertices. Some new upper bounds in terms of order and degrees for this number are found.
相似文献