3,258 research outputs found
Measure of Synchronism of Multidimensional Chaotic Sequences Based on Their Symbolic Representation in a T-Alphabet
A new approach to analysis of the synchronization of chaotic oscillations in
two (or more) coupled oscillators is described that makes it possible to reveal
changes in the structure of attractors and detect the appearance of
intermittency. The proposed method is based on a symbolic analysis developed
previously in the velocity-curvature space of multidimensional sequences and
maps. The method is tested by application to a Lorentz system. The results
confirm the informativity of the analyzer and reveal specific features of
changes in the structure of an attractor of the three-component test system.Comment: 6 pages, 3 figures, 1 table, Preprint version of article published
in: Technical Physics Letters, 2012, Vol. 38, No. 9, pp. 804-80
Estimation of the TQ-complexity of chaotic sequences
A new approach is proposed to the quantitative estimation of the complexity
of multidimensional discrete sequences in terms of the shapes of their
trajectories in the extended space of states. This approach is based on the
study of the structural properties of sequences and is suitable for estimating
the complexity of both chaotic and stochastic sequences. It is constructed on
the method, proposed earlier by the author, of symbolic CTQ-analysis of
multidimensional discrete sequences and mappings. The algorithm proposed
manipulates not only the frequency of occurrence of symbols, but also takes
into account their sequence order. An example (financial time series) is given
that demonstrates the application of the tools developed.Comment: 11 pages, 6 figures, 1 table, Paper 99 in Proceedings of the 1st IFAC
Conference MICNON 201
Generalized synchronization of multidimensional chaotic systems in terms of symbolic CTQ-analysis
A new approach is proposed to the analysis of generalized synchronization of
multidimensional chaotic systems. The approach is based on the symbolic
analysis of discrete sequences in the basis of a finite T-alphabet. In fact,
the symbols of the T-alphabet encode the shape (the geometric structure) of a
trajectory of a dynamical system. Investigation of symbolic sequences allows
one to diagnose various regimes of chaos synchronization, including generalized
synchronization. The characteristics introduced allow one to detect and study
the restructuring and intermittency behavior of attractors in systems (the time
structure of synchronization). The measure of T-synchronization proposed is
generalized without restrictions to complex ensembles of strongly nonstationary
and nonidentical large-dimensional oscillators with arbitrary configuration and
network (lattice) topology. The main features of the method are illustrated by
an example.Comment: 13 pages, 7 figures. arXiv admin note: substantial text overlap with
arXiv:1505.0431
Recursive Tangential-Angular Operator as Analyzer of Synchronized Chaos
A method for the quantitative analysis of the degree and parameters of
synchronization of the chaotic oscillations in two coupled oscillators is
proposed, which makes it possible to reveal a change in the structure of
attractors. The proposed method is tested on a model system of two
unidirectionally coupled logistic maps. It is shown that the method is robust
with respect to both the presence of a low-intensity noise and a nonlinear
distortion of the analyzed signal. Specific features of a rearranged structure
of the attractor of a driven subsystem in the example under consideration have
been studied.Comment: 7 pages, 5 figures, An expanded and corrected version of article
published in: Technical Physics Letters, 2011, Vol. 37, No. 8, pp. 784-78
Wormholes in the Braneworld
We discuss brane wormhole solution when classical brane action contains 4d
curvature. The equations of motion for the cases with R=0 and are
obtained. Their numerical solutions corresponding to wormhole are found for
specific boundary conditions
Analysis of the Time Structure of Synchronization in Multidimensional Chaotic Systems
A new approach is proposed to the integrated analysis of the time structure
of synchronization of multidimensional chaotic systems. The method allows one
to diagnose and quantitatively evaluate the intermittency characteristics
during synchronization of chaotic oscillations in the T-synchronization mode. A
system of two identical logistic mappings with unidirectional coupling that
operate in the developed chaos regime is analyzed. It is shown that the widely
used approach, in which only synchronization patterns are subjected to analysis
while desynchronization areas are considered as a background signal and removed
from analysis, should be considered as methodologically incomplete.Comment: 13 pages, 6 figures, Preprint version of article published in: J.
Exp. Theor. Phys., 2015, Vol. 120, No. 5, pp. 912-92
Comment on "Shallow donor states near a semiconductor-insulator-metal interface"
In a recent paper Hao et al. [Phys. Rev. B 80, 035329 (2009)] reported
variational calculations of energy spectrum for shallow hydrogenic donor in the
structure of semiconductor/insulator/metal with a new type of trial wave
function. They also performed calculations for semiconductor/insulator system
and found that their method gives energy values lower than those obtained by
MacMillen and Landman [Phys. Rev. B 29, 4524 (1984)]. As follows from these
results MacMillen and Landman have got much larger errors in energy values than
they expected. However we confirm that the theoretical approach suggested by
MacMillen and Landman gives rather accurate energy values for the system of
hydrogenic donor near the interface between semiconductor and insulator.Comment: 2 pages, 2 table
The class of second order quasilinear equations: models, solutions and background of classification
The paper is concerned with the unsteady solutions to the model of mutually
penetrating continua and quasilinear hyperbolic modification of the Burgers
equation (QHMB). The studies were focused on the peculiar solutions of models
in question. On the base of these models and their solutions, the ideas of
second order quasilinear models classification were developed.Comment: 11 pages, 6 figure
On a phenomenology of the accelerated expansion with a varying ghost dark energy
Subject of our study it is the accelerated expansion of the large scale
universe, where a varying ghost dark energy can take the role of the dark
energy. The model of the varying ghost dark energy considered in this work it
is a phenomenological modification of the ghost dark energy. Recently, three
other phenomenological models of the varying ghost dark energy have been
suggested and the model considered in this work will complete the logical chain
of considered modifications. The best fit of theoretical results to the
luminosity distance, has been used to obtain preliminary constraints on the
parameters of the models. This does help us to reduce amount of discussion. On
the other hand, detailed comparison of theoretical results with observational
data has been left as a subject of another discussion elsewhere. Moreover, a
look to considered models via and statefinder hierarchy analysis is
presented and discussed for different forms of interaction between the varying
ghost dark energy and cold dark matter
Implementation of deep learning algorithm for automatic detection of brain tumors using intraoperative IR-thermal mapping data
The efficiency of deep machine learning for automatic delineation of tumor
areas has been demonstrated for intraoperative neuronavigation using active
IR-mapping with the use of the cold test. The proposed approach employs a
matrix IR-imager to remotely register the space-time distribution of surface
temperature pattern, which is determined by the dynamics of local cerebral
blood flow. The advantages of this technique are non-invasiveness, zero risks
for the health of patients and medical staff, low implementation and
operational costs, ease and speed of use. Traditional IR-diagnostic technique
has a crucial limitation - it involves a diagnostician who determines the
boundaries of tumor areas, which gives rise to considerable uncertainty, which
can lead to diagnosis errors that are difficult to control. The current study
demonstrates that implementing deep learning algorithms allows to eliminate the
explained drawback.Comment: 7 pages, 5 figures, 2 table
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