185 research outputs found

    Localization-delocalization transition on a separatrix system of nonlinear Schrodinger equation with disorder

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    Localization-delocalization transition in a discrete Anderson nonlinear Schr\"odinger equation with disorder is shown to be a critical phenomenon - similar to a percolation transition on a disordered lattice, with the nonlinearity parameter thought as the control parameter. In vicinity of the critical point the spreading of the wave field is subdiffusive in the limit t+t\rightarrow+\infty. The second moment grows with time as a powerlaw tα\propto t^\alpha, with α\alpha exactly 1/3. This critical spreading finds its significance in some connection with the general problem of transport along separatrices of dynamical systems with many degrees of freedom and is mathematically related with a description in terms fractional derivative equations. Above the delocalization point, with the criticality effects stepping aside, we find that the transport is subdiffusive with α=2/5\alpha = 2/5 consistently with the results from previous investigations. A threshold for unlimited spreading is calculated exactly by mapping the transport problem on a Cayley tree.Comment: 6 pages, 1 figur

    E-pile model of self-organized criticality

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    The concept of percolation is combined with a self-consistent treatment of the interaction between the dynamics on a lattice and the external drive. Such a treatment can provide a mechanism by which the system evolves to criticality without fine tuning, thus offering a route to self-organized criticality (SOC) which in many cases is more natural than the weak random drive combined with boundary loss/dissipation as used in standard sand-pile formulations. We introduce a new metaphor, the e-pile model, and a formalism for electric conduction in random media to compute critical exponents for such a system. Variations of the model apply to a number of other physical problems, such as electric plasma discharges, dielectric relaxation, and the dynamics of the Earth's magnetotail.Comment: 4 pages, 2 figure

    Molecular marker screening of new promising wine grape clones

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    Fracton pairing mechanism for "strange" superconductors: Self-assembling organic polymers and copper-oxide compounds

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    Self-assembling organic polymers and copper-oxide compounds are two classes of "strange" superconductors, whose challenging behavior does not comply with the traditional picture of Bardeen, Cooper, and Schrieffer (BCS) superconductivity in regular crystals. In this paper, we propose a theoretical model that accounts for the strange superconducting properties of either class of the materials. These properties are considered as interconnected manifestations of the same phenomenon: We argue that superconductivity occurs in the both cases because the charge carriers (i.e., electrons or holes) exchange {\it fracton excitations}, quantum oscillations of fractal lattices that mimic the complex microscopic organization of the strange superconductors. For the copper oxides, the superconducting transition temperature TcT_c as predicted by the fracton mechanism is of the order of 150\sim 150 K. We suggest that the marginal ingredient of the high-temperature superconducting phase is provided by fracton coupled holes that condensate in the conducting copper-oxygen planes owing to the intrinsic field-effect-transistor configuration of the cuprate compounds. For the gate-induced superconducting phase in the electron-doped polymers, we simultaneously find a rather modest transition temperature of (23)\sim (2-3) K owing to the limitations imposed by the electron tunneling processes on a fractal geometry. We speculate that hole-type superconductivity observes larger onset temperatures when compared to its electron-type counterpart. This promises an intriguing possibility of the high-temperature superconducting states in hole-doped complex materials. A specific prediction of the present study is universality of ac conduction for TTcT\gtrsim T_c.Comment: 12 pages (including separate abstract page), no figure

    RESVERATROL IN KUBAN WINES

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    Purpose: The main purpose of viticulture is to improve the quality of the grapes, both to a greater extent for ampelotherapy and winemaking, and, to a lesser extent, to onotherapy. Methodology: The article highlights the results of perennial (from 2014) studies of 18 promising technical grape varieties from different zones of the Krasnodar Territory: Anapo-Taman, Central, as well as Amur from the Black Sea zone of the Krasnodar Territory and two control Western European world-famous and most common varieties Merlot and Cabernet-Sauvignon in the same zones. Result: The average values of resveratrol were found in wine materials from the varieties Vladimir and Dmitry (4.7 mg / dm3), Podlesny (3.9 mg / dm3), Saperavi Severny (3.5 mg / dm3), 40 let Octiabria (3.3 mg / dm3), Kurchansky and 40 let Pobedy (3.0 and 2.9 mg / dm3, respectively). On the other hand, as shown by the analysis of wine materials, the Antaris, Varyushkin, Mitsar and Plechistik varieties synthesize a lower content of resveratrol (1.0 and 0.9 mg / dm3, respectively). Applications: This research can be used for the universities, teachers and education students. Novelty/Originality: In this research, the model of resveratrol in Kuban wines is presented in a comprehensive and complete manner

    Algorithmic statistics: forty years later

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    Algorithmic statistics has two different (and almost orthogonal) motivations. From the philosophical point of view, it tries to formalize how the statistics works and why some statistical models are better than others. After this notion of a "good model" is introduced, a natural question arises: it is possible that for some piece of data there is no good model? If yes, how often these bad ("non-stochastic") data appear "in real life"? Another, more technical motivation comes from algorithmic information theory. In this theory a notion of complexity of a finite object (=amount of information in this object) is introduced; it assigns to every object some number, called its algorithmic complexity (or Kolmogorov complexity). Algorithmic statistic provides a more fine-grained classification: for each finite object some curve is defined that characterizes its behavior. It turns out that several different definitions give (approximately) the same curve. In this survey we try to provide an exposition of the main results in the field (including full proofs for the most important ones), as well as some historical comments. We assume that the reader is familiar with the main notions of algorithmic information (Kolmogorov complexity) theory.Comment: Missing proofs adde

    Резервирование в тяговом приводе локомотива

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    The main purpose of the presented work is to study the possibility of using for rail transport (in particular, for development of promising structures and components of locomotive traction electric drive) of new technical solutions for transmission gears. A design development of gear drive is offered with high processability indices for manufacturing and operation. The possibility of implementation of layout diagram of traction drive with parallel power flows the basis of this gear drive is shown.Основной целью представленной работы является исследование возможности применения на железнодорожном транспорте (в частности, при разработке перспективных конструкций и элементов тягового электропривода локомотива) новых технических решений для передаточных механизмов. Предложена конструкторская разработка зубчатой передачи с высокими показателями технологичности при изготовлении и эксплуатации. Обоснована возможность реализации на базе этой зубчатой передачи компоновочной схемы тягового привода с параллельными потоками мощности
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