17 results on '"deterministic chaos"'
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2. Full-Bridge power resonant converter for the arcjet thruster of a small spacecraft
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V. V. Fedyanin, V. V. Shalay, V. K. Fedorov, P. S. Yachmenev, and I. S. Vavilov
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resonant converters ,arcjet thruster ,small spacecraft ,low-orbit grouping ,thermoacoustics ,deterministic chaos ,chaotic dynamics ,Engineering (General). Civil engineering (General) ,TA1-2040 - Abstract
In this paper, the applied problems of designing a bridge resonant converter with a high-voltage arc ignition system in the channel of an electric arc motor is solved. The development of a bridge resonant power supply is presented, a review and analysis of power sources of arcjet thruster of various capacities is carried out. The theoretical aspects of calculating the main parameters of the source are considered. The transfer function describing the gain of the resonant circuit of the power supply is given. With the help of the transfer function, gain diagrams are constructed for various values of the Q-factor of the contour. A prototype of a power supply, a starting system and an arcjet thruster is presented. A series of experiments aimed at identifying the operability of the source is carried out. According to the experimental results, the maximum output power of the source wiz 182,4 watts, and the maximum efficiency is 87,5 %. Frequency spectra of the output current of the power supply are obtained. The current-voltage characteristics for the Ar and N2 are constructed. In the course of the study, phenomena related to the chaotic dynamics of the arc in the engine channel are discovered. Chaotic fluctuations are observed at the moment of starting the engine and disappeared after steady-state operation.
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- 2023
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3. Representation of exact trajectory solutions for chaotic one-dimensional maps in Schroder form
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Anikin, Valerij Mihajlovich
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iteration theory ,deterministic chaos ,one-dimensional maps ,schroder equation ,exact solutions ,Physics ,QC1-999 - Abstract
Purpose of the article is to illustrate the genesis, meaning and significance of the functional Schroder equation, introduced in the theory of iterations of rational functions, for the theory of deterministic chaos by analytical calculations of exact trajectory solutions, invariant densities and Lyapunov exponents of one-dimensional chaotic maps. We demonstrate the method for solving the functional Schroder equation for various chaotic maps by passing to a topologically conjugate mappings, for which finding the exact trajectory solution is a simpler mathematical procedure. Results of the analytical solution of the Schroder equation for 12 chaotic mappings of various types and the calculation of the corresponding expressions for exact trajectory solutions, invariant densities and Lyapunov exponents are presented. Conclusion is made about the methodological expediency of formulating and solving the Schroder equations by the study of the dynamics of one-dimensional chaotic mappings.
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- 2023
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4. Numerical Study of the Effect of Stochastic Disturbances on the Behavior of Solutions of Some Differential Equations
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Arsenij Firsov, Igor Inovenkov, Vasilij Tikhomirov, and Vladimir Nefedov
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system of lorentz differential equations ,nonlinear dynamics ,deterministic chaos ,stochastic perturbations ,Electronic computers. Computer science ,QA75.5-76.95 - Abstract
Nowadays interest of the deterministic differential system of Lorentz equations is still primarily due to the problem of gas and fluid turbulence. Despite numerous existing systems for calculating turbulent flows, new modifications of already known models are constantly being investigated. In this paper we consider the effect of stochastic additive perturbations on the Lorentz convective turbulence model. To implement this and subsequent interpretation of the results obtained, a numerical simulation of the Lorentz system perturbed by adding a stochastic differential to its right side is carried out using the programming capabilities of the MATLAB programming environment.
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- 2021
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5. COMBINING METHODS OF FREQUENCY FILTERING AND NONLINEAR ANALYSIS FOR SOMNOLOGICAL STUDY OF EEG SIGNALS
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O I Antipov and A V Zakharov
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fractals ,deterministic chaos ,hypnogram ,frequency analysis ,electroencephalography ,Medicine - Abstract
Aim - combined use of frequency and nonlinear analysis methods for obtaining hypnograms by analyzing electroencephalographic (EEG) signals during somnological studies. Methods. Frequency filtering methods were used for preliminary treatment of EEG signals before the following nonlinear analysis. As non-linear methods of analysis we used fractal methods of deterministic chaos, such as Hurst’s method of the normalized amplitude, approximate entropy method, calculation of the correlation integral by Grassberger and Procaccia’s method. For the possibility of applying the last two methods we used quasi phase space recovery method according to the Taken’s theorem. As a result of non-linear analysis we obtained hypnograms reflecting the transition between the stages of sleep in patients undergoing somnological examination. To assess the reliability of the results, they were compared to the hypnograms obtained by the classical method based on the rules of Rehchaffen and Keyls. Also the problems associated with the occurrence of various types of interference were considered and methods for reducing their influence on the final results were suggested. Results. We can conclude that using these methods with appropriate selection of the parameters, employing the necessary normalization of raw data, and averaging the results allow us to obtain hypnogram having a full match of defined phases of sleep for about half of the periods recorded by EEG. To obtain these results it is sufficient to use only one channel of EEG recording.
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- 2016
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6. INFORMATION TRANSMISSION BASED ON SPECTRUM MANIPULATION OF A WIDEBAND CHAOTIC SIGNAL
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O. V. Zemlyaniy
- Subjects
a nonlinear dynamical system with delayed feedback ,broadband data transmission system ,deterministic chaos ,Electronics ,TK7800-8360 - Abstract
Application of chaotic signals in modern radar and telecommunications is an actual task that can significantly extend the functionality of these systems and improve their performance. In this paper, a method for information transmission using chaotic signal generated by nonlinear dynamical system with delayed feedback of ring type has been suggested. Modulating information sequence controls the parameter of non-linear element, so that it switches the chaotic modes and changes the spectral structure of the signal transmitted to the communication channel. A non-coherent reception was used for demodulation of the received message. The effectiveness of this method of information transmission for the covert operation of communication system in a complex interference environment has been shown.
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- 2015
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7. Features of the determined chaos modes of dc voltage converters for wind and solar power stations
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Vladimir Kuzmich Fedorov and Viktor Viktorovich Fedyanin
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deterministic chaos ,DC-DC converters ,control system ,bifurcation ,dynamic chaos ,Engineering geology. Rock mechanics. Soil mechanics. Underground construction ,TA703-712 - Abstract
Relevance of the researches is defined by the necessity to increase the efficiency of converters for the needs of renewable energy. The strict and conflicting requirements are often imposed to the control algorithms of DC voltage converters used in solar and wind power. The theory of deterministic chaos may be one of the ways of solving the problem of improving the algorithms. The aim of the research is to study and develop the control systems for DC-DC converters which allows working both in periodic mode and in deterministic chaos mode; to develop a physical model of DC-DC converter including the control system operating in deterministic chaos mode; make the voltage feedback circuit for stabilizing the output voltage at the given level. Research method: a review of patent and literature on the topic. The mathematical and experimental methods of investigation of the DC-DC converters were used. The method of mathematical modeling is based on preparation of electrical systems equations solution. The method of experimental research is based on the study of the output graphs, taken from the physical model of the DC-DC converters. Results. The authors have developed the physical model of the DC-DC converter with the control system operating in the deterministic chaos mode. The results show that the method of controlling the DC-DC converters with the help of deterministic chaos reduces electromagnetic interference, and improves significantly energy efficiency. The results obtained in the study can be used both at the stage of designing the power supplies in this class, and for further research and development of new control systems, including the control by deterministic chaos.
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- 2017
8. DETERMINISTIC CHARACTER OF CHANGES OF THE CASPIAN SEA LEVEL AND ITS QUANTITATIVE PARAMETERS
- Author
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U. G. Magomedbekov
- Subjects
caspian sea ,level ,dynamics ,time series analysis ,attractor ,phase space ,deterministic chaos ,Ecology ,QH540-549.5 - Abstract
Abstract. The results of determination of parameters of dynamics of Caspian Sea level changes were studied. We determined quantities and dimensions of the phase space and the attractor, we calculated exponents of Lyapunov and assessed value of Kolmogorov – Sinai entropy based on analysis of time series by the change in the reservoir for 1931–2009.Introduction. When interpreting the data on oscillatory phenomena an application of the theory of self-organization approaches becomes interesting, as it allows to set in a certain extent the behavior and evolution of the system regardless the nature of occurring in them processes.Methods. During the preparation of article we applied a complex approach of nonlinear dynamics, consisting of the use of the discrete Fourier transform, the reconstruction of the dynamics of the time series with the construction of phase portraits and determining the dimensions of the phase space and attractor, calculation of Lyapunov exponents and Kolmogorov – Sinai entropy.Results. It is found that Fourier spectrum–discrete; attractor dimension is expressed in non-integer number, and it is more than three; dimension of the phase space is equal to five; values of Lyapunov exponents correspond to: λ1> 0, λ2 = 0, λ3< 0; KS-entropy value is greater than zero (h = 0,018 ± 0,002); characteristic time that can be predicted by changes in the level corresponding to 58 - 60 days.Conclusion. The analysis conducted by methods of nonlinear dynamics shows deterministic character of Caspian Sea level changes for 1931–2009 and realization of dynamic chaos.
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- 2014
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9. Сhaotic oscillator for neural networks
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деÑеÑминиÑованнÑй Ñ Ð°Ð¾Ñ ,Aihara neuron ,logistic map ,deterministic chaos ,логиÑÑиÑеÑкое оÑобÑажение ,chaotic oscillator ,chaotic oscillatory neural networks ,Ñ Ð°Ð¾ÑиÑеÑкий оÑÑиллÑÑÐ¾Ñ ,нейÑон ÐÐ¹Ñ Ð°ÑÑ ,Ñ Ð°Ð¾ÑиÑеÑкие оÑÑиллÑÑоÑнÑе нейÑоннÑе ÑеÑи - Abstract
ÐбÑÐµÐºÑ Ð¸ÑÑÐ»ÐµÐ´Ð¾Ð²Ð°Ð½Ð¸Ñ â Ñ Ð°Ð¾ÑиÑеÑÐºÐ°Ñ Ð¾ÑÑиллÑÑоÑÐ½Ð°Ñ Ð½ÐµÐ¹ÑÐ¾Ð½Ð½Ð°Ñ ÑеÑÑ.Ð¦ÐµÐ»Ñ ÑабоÑÑ â ÑазÑабоÑка и иÑÑледование модели Ñ Ð°Ð¾ÑиÑеÑкой оÑÑиллÑÑоÑной нейÑонной ÑеÑи.Ð ÑезÑлÑÑаÑе иÑÑÐ»ÐµÐ´Ð¾Ð²Ð°Ð½Ð¸Ñ Ð±Ñли полÑÑÐµÐ½Ñ Ð¼Ð¾Ð´ÐµÐ»Ð¸ блоков, Ð½ÐµÐ¾Ð±Ñ Ð¾Ð´Ð¸Ð¼Ñе Ð´Ð»Ñ Ð¿Ð¾ÑÑÑÐ¾ÐµÐ½Ð¸Ñ Ð°Ð¿Ð¿Ð°ÑаÑной ÑеализаÑии Ñ Ð°Ð¾ÑиÑеÑкой оÑÑиллÑÑоÑной нейÑонной ÑеÑи в инÑегÑалÑном иÑполнении. ÐÑли опÑÐµÐ´ÐµÐ»ÐµÐ½Ñ ÐºÐ»ÑÑевÑе паÑамеÑÑÑ ÑÑÐ¸Ñ Ð¼Ð¾Ð´ÐµÐ»ÐµÐ¹ блоков, Ð´Ð»Ñ ÑÑÐ°Ð²Ð½ÐµÐ½Ð¸Ñ Ñ Ð¿Ð°ÑамеÑÑами аналогиÑнÑÑ Ð±Ð»Ð¾ÐºÐ¾Ð² из иÑполÑзованнÑÑ Ð¸ÑÑоÑников. Ðз полÑÑеннÑÑ Ð¼Ð¾Ð´ÐµÐ»ÐµÐ¹ бÑла Ñоздана Ð¼Ð¾Ð´ÐµÐ»Ñ Ñ Ð°Ð¾ÑиÑеÑкой оÑÑиллÑÑоÑной нейÑонной ÑеÑи. ÐмеÑÑе Ñ ÑÑим бÑли ÑÐ¾Ð·Ð´Ð°Ð½Ñ Ð¿ÑогÑаммнÑе инÑÑÑÑменÑÑ Ð´Ð»Ñ Ð¾Ð±ÐµÑпеÑÐµÐ½Ð¸Ñ ÐµÑ ÑабоÑÑ. ÐÐ¾Ð´ÐµÐ»Ñ Ð±Ñла пÑоÑеÑÑиÑована на пÑимеÑе ÑеÑÐµÐ½Ð¸Ñ Ð·Ð°Ð´Ð°Ñ ÐºÐ»Ð°ÑÑеÑизаÑии. ÐолÑÑеннÑе ÑезÑлÑÑаÑÑ Ð¼Ð¾Ð³ÑÑ Ð±ÑÑÑ Ð¿ÑÐ¸Ð¼ÐµÐ½ÐµÐ½Ñ Ð´Ð»Ñ ÑÐ¾Ð·Ð´Ð°Ð½Ð¸Ñ Ð°Ð¿Ð¿Ð°ÑаÑной ÑеализаÑии Ñ Ð°Ð¾ÑиÑеÑкой оÑÑиллÑÑоÑной нейÑонной ÑеÑи в инÑегÑалÑном иÑполнении Ð´Ð»Ñ Ð´Ð°Ð»ÑнейÑего пÑÐ¸Ð¼ÐµÐ½ÐµÐ½Ð¸Ñ Ð² ÑоÑÑаве вÑÑиÑлиÑелÑнÑÑ ÑÑÑÑойÑÑв как оÑделÑнÑм блоком инÑегÑалÑной ÑÑ ÐµÐ¼Ñ, Ñак и в виде ÑамоÑÑоÑÑелÑной оÑделÑной инÑегÑалÑной ÑÑ ÐµÐ¼Ñ. Ðанное ÑеÑение Ð¼Ð¾Ð¶ÐµÑ Ð¿ÑивеÑÑи к поÑенÑиалÑÐ½Ð¾Ð¼Ñ Ð¿Ð¾Ð²ÑÑÐµÐ½Ð¸Ñ ÑнеÑгоÑÑÑекÑивноÑÑи и ÑкоÑоÑÑи ÑабоÑÑ ÑÑÑÑойÑÑв, где Ð½ÐµÐ¾Ð±Ñ Ð¾Ð´Ð¸Ð¼Ð¾ ÑеÑение Ð·Ð°Ð´Ð°Ñ ÐºÐ»Ð°ÑÑеÑизаÑии. Ðа наÑÑоÑÑее вÑÐµÐ¼Ñ Ð² миÑовой пÑакÑике имееÑÑÑ Ð¾Ð±ÑиÑнÑй запÑÐ¾Ñ Ð½Ð° ÑÑÑÑойÑÑва, ÑпоÑобнÑе ÑеÑаÑÑ Ñакие задаÑи., The subject of the graduate qualification work is âchaotic oscillator for neural networksâ.The given work is devoted to development and research of a chaotic oscillatory neural network model.As a result of the study, the block models necessary for building a hardware implementation of a chaotic oscillatory neural network in an integrated design were obtained. The key parameters of these block models were determined for comparison with the parameters of similar blocks from the used references. From the obtained models, a model of a chaotic oscillatory neural network was created. Along with this, software tools were created to ensure its operation. The model was tested on the clustering problem examples. The obtained results can be used to create a hardware implementation of a chaotic oscillatory neural network in an integrated design for further use as part of computing devices as a block inside integrated circuit, or as an independent separate integrated circuit. This solution can lead to a potential increase in energy efficiency and working speed of devices where it is necessary to solve clustering problems. At present, in world practice there is an extensive request for devices capable of solving such problems.
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- 2022
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10. The measuring converter indifferent to chaotic excitation of a sensitive element
- Author
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Korotkii V. P. and Il’in V. N.
- Subjects
flaxgate sensor ,magnetic-modulation converter ,ferro-modulation converter ,dynamical chaos ,deterministic chaos ,Electrical engineering. Electronics. Nuclear engineering ,TK1-9971 - Abstract
The scheme of the converter insensitive to occurrence in it of dynamic chaos, with wide pass band and the linear transfer characteristic is offered. The converter can be used as a magnetic antenna for receiving the magnetic component of electromagnetic field in the radio frequency spectrum, in magnetic noise analyzers, for determination of the shape of the magnetic pulses.
- Published
- 2011
11. Deterministic chaos-based data encryption
- Subjects
деÑеÑминиÑованнÑй Ñ Ð°Ð¾Ñ ,deterministic chaos ,изобÑажение ,UACI ,algorithm ,ÑиÑÑование ,analysis ,chaotic system ,NPCR ,алгоÑиÑм ,Ñ Ð°Ð¾ÑиÑеÑÐºÐ°Ñ ÑиÑÑема ,image ,encryption ,анализ - Abstract
Тема вÑпÑÑкной квалиÑикаÑионной ÑабоÑÑ: «ШиÑÑование даннÑÑ Ð½Ð° базе деÑеÑминиÑованного Ñ Ð°Ð¾Ñа». ÐÐ°Ð½Ð½Ð°Ñ ÑабоÑа поÑвÑÑена изÑÑÐµÐ½Ð¸Ñ ÑиÑÑем деÑеÑминиÑованного Ñ Ð°Ð¾Ñа и ÑеализаÑии алгоÑиÑмов ÑиÑÑÐ¾Ð²Ð°Ð½Ð¸Ñ Ð´Ð°Ð½Ð½ÑÑ , в ÑаÑÑноÑÑи изобÑажений, а Ñакже Ð°Ð½Ð°Ð»Ð¸Ð·Ñ ÑиÑÑем ÑиÑÑованиÑ. ÐадаÑи, коÑоÑÑе ÑеÑалиÑÑ Ð² Ñ Ð¾Ð´Ðµ вÑÐ¿Ð¾Ð»Ð½ÐµÐ½Ð¸Ñ ÑабоÑÑ: 1.ÐÑÑледование Ñ Ð°Ð¾ÑиÑеÑÐºÐ¸Ñ ÑиÑÑем 2.ÐзÑÑение ÑÑÑеÑÑвÑÑÑÐ¸Ñ Ð¼ÐµÑодов ÑиÑÑÐ¾Ð²Ð°Ð½Ð¸Ñ 3.РеализаÑÐ¸Ñ Ð°Ð»Ð³Ð¾ÑиÑмов ÑиÑÑÐ¾Ð²Ð°Ð½Ð¸Ñ 4.Ðнализ ÑиÑÑем ÑиÑÑÐ¾Ð²Ð°Ð½Ð¸Ñ ÐоÑÑÑоение гÑаÑиков ÑазовÑÑ Ð¿Ð¾ÑÑÑеÑови биÑÑÑкаÑионнÑÑ Ð´Ð¸Ð°Ð³Ñамм ÑиÑÑем деÑеÑминиÑованного Ñ Ð°Ð¾Ñа, а Ñакже гиÑÑогÑамм и гÑаÑиков ÑезÑлÑÑаÑов анализа ÑиÑÑем ÑиÑÑÐ¾Ð²Ð°Ð½Ð¸Ñ Ð±Ñло пÑоизведено в ÑÑеде MATLAB. РеализаÑÐ¸Ñ Ð°Ð»Ð³Ð¾ÑиÑмов ÑиÑÑÐ¾Ð²Ð°Ð½Ð¸Ñ Ð±Ñла пÑоизведена в ÑÑеде ÑазÑабоÑки Eclipse на ÑзÑке пÑогÑаммиÑÐ¾Ð²Ð°Ð½Ð¸Ñ Java. Ðнализ алгоÑиÑмов пÑоводилÑÑ ÑÑаÑиÑÑиÑеÑким и диÑÑеÑенÑиалÑнÑм меÑодами. Ð ÑезÑлÑÑаÑе бÑло пÑоизведено ÑÑавнение ÑазÑабоÑаннÑÑ Ð°Ð»Ð³Ð¾ÑиÑмов ÑиÑÑованиÑ, Ñ Ð¿Ð¾Ð¼Ð¾ÑÑÑ Ð¿Ñоведенного Ñанее анализа, и вÑбÑан наилÑÑÑий алгоÑиÑм. Ð ÑÐ°Ð¼ÐºÐ°Ñ Ð¿Ñоведенного иÑÑÐ»ÐµÐ´Ð¾Ð²Ð°Ð½Ð¸Ñ Ð»ÑÑÑим алгоÑиÑмом оказалÑÑ Ð°Ð»Ð³Ð¾ÑиÑм ÑиÑÑованиÑ, оÑнованнÑй на базе деÑеÑминиÑованного Ñ Ð°Ð¾Ñа. Таким обÑазом, ÑледÑÐµÑ Ð¿ÑодолжаÑÑ Ð¸ÑÑÐ»ÐµÐ´Ð¾Ð²Ð°Ð½Ð¸Ñ Ð² облаÑÑи ÑиÑÑÐ¾Ð²Ð°Ð½Ð¸Ñ Ð½Ð° базе ÑиÑÑем деÑеÑминиÑованного Ñ Ð°Ð¾Ñа, ÑлÑÑÑаÑÑ Ð°Ð»Ð³Ð¾ÑиÑÐ¼Ñ Ð¸ ÑлÑÑÑаÑÑ Ð¸Ñ Ð¿ÑоизводиÑелÑноÑÑÑ., The subject of the graduate qualification work is «Deterministic chaos-based data encryption». This work is devoted to the research of deterministic chaos systems and the implementation of data encryption algorithms, in particular images, as well as the analysis of encryption systems. Tasks that were solved in the course of the work: 1.Research of chaotic system 2.Research of existing encryption methods 3.Realization of encryption algorithms 4.Encryption system analysis The formation of phase portraits plots and bifurcation diagrams of deterministic chaos system, as well as histograms and plots of the analysis results of encryption systems was implemented in the MATLAB. Algorithmsâ realizations were implemented in the Eclipse IDE in the Java programming language. The algorithms were analyzed by using statistical and differential methods. As a result, a comparison of the developed encryption algorithms was made, using the statistical and differential analysis, and the best algorithm was selected. Within the framework of the research, the algorithm based on deterministic chaos was chosen as the best encryption algorithm. Thus, it is necessary to continue research in the field of chaos-based encryption and improve algorithms and their productivity.
- Published
- 2021
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12. Determined chaos-based secure data transmission system
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nist ,python ,messenger ,deterministic chaos ,информационные технологии ,системный анализ ,system analysis ,information technologies ,детерминированный хаос - Abstract
Тема выпускной квалификационной работы: «Система передачи данных на основе детерминированного хаоса». Данная работа посвящена исследованию путей повышения устойчивости ко взлому цифровых каналов передачи данных путём применения систем шифрования на базе генераторов детерминированного хаоса. Задачи, которые решались в ходе работы: 1. Анализ динамических свойств нескольких систем детерминированного хаоса. 2. Оценка меры случайности числовых двоичных последовательностей, генерируемые запрограммированными хаотическими системами путем применения статистических тестов и выбор наилучшей модели по результатам тестов. 3. Применение синхронизации хаотических систем с применением технологии blockchain. 4. Разработка концепта компьютерного приложения, предоставляющее возможность передачи защищенных данных, используя уже синхронизированные системы детерминированного хаоса, а также оценка меры скрытности передаваемой информации. Таким образом в результате работы мы получили концепт системы передачи данных на основе детерминированного хаоса, который можно реализовать и попробовать применять как новое ветвление мессенджеров., Theme of the final qualification work: "A data transmission system based on deterministic chaos." This work is devoted to the study of ways to increase the resistance to cracking of digital data transmission channels by using encryption systems based on deterministic chaos generators. Tasks that were solved in the course of work: 1. Analysis of the dynamic properties of several systems of deterministic chaos. 2. Evaluation of the measure of randomness of numerical binary sequences generated by programmed chaotic systems by applying statistical tests and choosing the best model based on test results. 3. The use of synchronization of chaotic systems using blockchain technology. 4. Development of the concept of a computer application that provides the ability to transfer secure data using already synchronized systems of deterministic chaos, as well as an assessment of the degree of secrecy of the transmitted information. Thus, as a result of work, we got the concept of a data transmission system based on deterministic chaos, which can be implemented and tried to be used as a new branch of instant messengers.
- Published
- 2020
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13. СЛУЧАЙНОСТЬ ИЛИ ХАОТИЧНОСТЬ: ФРАКТАЛЬНЫЙ АНАЛИЗ ПРИРОДЫ РЯДОВ НАБЛЮДЕНИЙ
- Subjects
deterministic chaos ,phase space ,correlation integral ,фазовое пространство ,корреляционный интеграл ,сходимость фрактальной размерности ,convergence of fractal dimension ,детерминированный хаос - Abstract
Рассматриваемая статья посвящена применению численного фрактального анализа к задаче обработки нестационарных временных рядов. Принципиальным вопросом анализа временных последовательностей, отражающих динамику многих реальных процессов, является их нестационарность и наличие признаков хаотической динамики. Интерпретация указанных наблюдений как реализаций процессов динамического хаоса позволяет объяснить низкую эффективность диагностических схем, основанных на статистической обработке информации. Данный подход дает потенциальную возможность для построения нового класса прогностических индикаторов, базирующихся на концепции фрактальной математики. Предложена методика идентификации природы стохастических и хаотических нелинейных процессов, порожденных нестационарными временными рядами наблюдений. Изучены фрактальные характеристики процессов. В частности, приведены кривые расходимости корреляционной размерности в зависимости от размерности фазового пространства. Проведен анализ сходимости фрактальной размерности на основе оценки аппроксимированной энтропии. Представлен пример детерминированной динамики, для которого корреляционная размерность равна постоянной величине, а аппроксимированная энтропия - нулю. Показан вид соответствующего ему регулярного аттрактора и определены значения его параметров. Математическое описание последовательностей наблюдений на основе моделей динамического хаоса позволяет сформулировать задачу нелинейной классификации изучаемых временных рядов. Подобная классификация основана на новых мерах неопределенности и представляет основу для дальнейших фундаментальных исследований., The considered article is devoted to the disclosing numerical capabilities of fractal analysis in the processing of non-stationary time series. The fundamental point of the analysis of time series is their unsteadiness and signs of chaotic dynamics. The interpretation of these observations, a realization of the process of dynamic chaos, lets explain the low efficiency of diagnostic procedures based on the statistical processing of information. This approach provides the potential to build a new class of prognostic indicators, based on the fractal mathematics concepts. The method of identifying the nature of stochastic and chaotic non-linear processes generated by non-stationary time series observations is proposed. In the article the fractal characteristics of the processes is studied. In particular, the correlation dimension curves divergence depending on the dimension of the phase space are given, and a convergence analysis of fractal dimension based on an assessment of approximate entropy is performed. We present an example of the deterministic dynamics for which the correlation dimension is equal to a constant value, and approximated entropy is zero. In the article we show a corresponding regular attractor and the values of its parameters. The mathematical description of sequences of observations on the basis of dynamic chaos models allows us to formulate the problem of non-linear classification of the studied time series. This classification is based on the new measures of uncertainty and provides the basis for further fundamental research., №1 (2018)
- Published
- 2018
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14. Application of nonlinear dynamics methods in prepropriate analysis of the morbidity indicators in Ukraine by various skin pathology
- Subjects
deterministic chaos ,Lyapunov characteristic indices ,фазовое пространство ,аттрактор ,кожные заболевания ,качественный анализ ,phase space ,attractor ,индекс фрактальности ,fractal index ,skin diseases ,характеристические показатели Ляпунова ,qualitative analysis ,time series ,детерминированный хаос ,временные ряды - Abstract
В работе представлены результаты применения методов нелинейной динамики для предпрогнозного анализа временных рядов, характеризующих распространенность различных кожных заболеваний в Украине. Рассматривается метод фрактального анализа, основанный на вычислении индекса фрактальности, оценка хаотичности динамики с помощью характеристических показателей Ляпунова, процедура восстановления фазовой траектории. The article presents the application results of the nonlinear dynamics methods for the preprediction analysis of time series characterizing the prevalence of various skin diseases in Ukraine. The fractal analysis method based on the calculation of the fractality index is considered, estimation of the randomness of the dynamics using Lyapunov's characteristic exponents, the procedure for reconstructing the phase trajectory.
- Published
- 2018
15. The Meteorological Service Model of Air and Space Forces Using the Fractal Theory
- Author
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Mikhailov, Vladimir V. and Kirnosov, Sergey L.
- Subjects
модель управления ,stability systems ,deterministic chaos ,устойчивость систем ,метеорологическая неопределенность ,условия погоды ,meteorological uncertainty ,fractal structure ,детерминированный хаос ,фрактальная структура ,model of control ,weather conditions - Abstract
Воздушно-космические силы России способны выполнять широкий спектр боевых авиационных задач в различных метеорологических условиях. Это вызывает значительные изменения во взглядах на роль и место авиации в военных конфликтах, а также на формы, способы ее боевого применения и обеспечения, в том числе и метеорологического. Высокая чувствительность параметров функционирования авиационных систем к метеоусловиям зачастую приводит к невозможности использования традиционных математических методов при построении системы управления в сложных условиях погоды. Поэтому в работе построена модель метеорологического обеспечения авиационных систем с использованием основных элементов теории фракталов и теории детерминированного хаоса, что позволило учесть различные сочетания диагностических и прогностических метеорологических способов при поддержке принятия решений в условиях неопределенности метеорологической информации, а также выполнить учет степени хаотичности функционирования всей системы в целом Air and space forces of Russia capable of performing a wide range of combat aircraft tasks in various weather conditions. This causes considerable changes in views on the place and role of aviation in military conflicts and on the forms, methods of its combat application and service, including meteorological. The high sensitivity of parameters of functioning of aviation systems weather conditions often leads to the impossibility of use of traditional mathematical methods in building management systems under difficult conditions of weather. Therefore, the paper built the model of meteorological support of aviation systems using the basic elements of the theory of fractals and deterministic chaos theory, which allowed to take into account various combinations of diagnostic and prognostic meteorological methods to support decision making under uncertainty weather information, and perform an extent that there is a chaotic functioning of the system as a whole
- Published
- 2016
16. Features of the determined chaos modes of dc voltage converters for wind and solar power stations
- Author
-
Fedorov, Vladimir Kuzmich and Fedyanin, Viktor Viktorovich
- Subjects
deterministic chaos ,системы управления ,DC-DC converters ,dynamic chaos ,bifurcation ,детерминический хаос ,бифуркации ,динамический хаос ,control system ,преобразователи постоянного напряжения - Abstract
Актуальность проводимых исследований определяется необходимостью повышения энергоэффективности преобразовательных устройств для нужд возобновляемой энергетики. К алгоритмам управления преобразователей постоянного напряжения, применяемых в гелио- и ветроэлектростанциях, предъявляются повышенные и зачастую противоречивые требования. Одним из путей решения задачи совершенствования этих алгоритмов может служить теория детерминированного хаоса. Цель работы: исследование и создание системы управления для преобразователей постоянного напряжения, позволяющей работать как в периодическом режиме, так и в режиме детерминированного хаоса; создание физической модели преобразователя постоянного напряжения, включающего в себя систему управления, работающую в режиме детерминированного хаоса, а также разработка контура обратных связей по напряжению для стабилизации выходного напряжения на заданном уровне. Метод исследования. Проведен обзор патентных и литературных источников по данной теме. Использован математический и экспериментальный метод исследования преобразователей постоянного напряжения. Метод математического моделирования основан на составлении решении уравнений электрических систем. Метод экспериментального исследования основан на изучении выходных диаграмм, снятых с физической модели преобразователей постоянного напряжения. Результаты. Создана физическая модель преобразователя постоянного напряжения с системой управления, работающей в режиме детерминированного хаоса. Полученные в ходе исследования результаты, показывают, что способ управления преобразователем постоянного напряжения с помощью детерминированного хаоса уменьшает электромагнитные помехи, а также значительно повышает энергоэффективность. Результаты, полученные в ходе исследования, могут быть использованы как на стадии проектировки источников питания такого класса, так и для проведения дальнейших исследований и разработок новых систем управления, включающих в себя управление с помощью детерминированного хаоса. Relevance of the researches is defined by the necessity to increase the efficiency of converters for the needs of renewable energy. The strict and conflicting requirements are often imposed to the control algorithms of DC voltage converters used in solar and wind power. The theory of deterministic chaos may be one of the ways of solving the problem of improving the algorithms. The aim of the research is to study and develop the control systems for DC-DC converters which allows working both in periodic mode and in deterministic chaos mode; to develop a physical model of DC-DC converter including the control system operating in deterministic chaos mode; make the voltage feedback circuit for stabilizing the output voltage at the given level. Research method: a review of patent and literature on the topic. The mathematical and experimental methods of investigation of the DC-DC converters were used. The method of mathematical modeling is based on preparation of electrical systems equations solution. The method of experimental research is based on the study of the output graphs, taken from the physical model of the DC-DC converters. Results. The authors have developed the physical model of the DC-DC converter with the control system operating in the deterministic chaos mode. The results show that the method of controlling the DC-DC converters with the help of deterministic chaos reduces electromagnetic interference, and improves significantly energy efficiency. The results obtained in the study can be used both at the stage of designing the power supplies in this class, and for further research and development of new control systems, including the control by deterministic chaos.
- Published
- 2016
17. On multiextremality in the estimation problems of deterministic chaos systems
- Author
-
Elsakov, S. M. and Shiryaev, V. I.
- Subjects
deterministic chaos ,УДК 681.511.4 ,global optimization ,нелинейная система ,глобальная оптимизация ,nonlinear system ,детерминированный хаос ,системы автоматического управления - Abstract
Рассматриваются нелинейные динамические системы, привлекаемые либо для описания протекания некоторых процессов, либо для описания остатков при использовании линейных моделей. Для этих систем формулируется задача оценивания состояния (а также параметрической идентификации) на основе метода максимального правдоподобия. Для решения поставленной задачи предлагается использовать однородные алгоритмы глобальной оптимизации. Приводятся основные теоремы о линейном виде критерия для однородных алгоритмов глобальной оптимизации, о достаточном условии сходимости однородного алгоритма глобальной оптимизации. Приводятся результаты оценивания состояния для одномерной динамической нелинейной системы. The nonlinear dynamic systems used for the modeling of some processes or remainders when using linear models are considered. The problem of state estimation (as well as parametric identification) on the basis of maximum likelihood method is formulated. To solve the problem it is proposed to use homogeneous algorithms of global optimization. The main theorems about the linear type of criterion for homogeneous algorithms of global optimization and about the sufficient condition of convergence of homogeneous algorithm of global optimization are given. The results of state estimation for one-dimensional dynamic nonlinear system are given.
- Published
- 2009
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