Experiments on intrinsic and thermally induced chaos in an rf-driven Josephson junction
DEFF Research Database (Denmark)
Davidson, A.; Dueholm, B.; Beasley, M. R.
1986-01-01
We report detailed measurements of low-frequency noise due to microwaves applied to a real Josephson tunnel junction. An intrinsically chaotic region is apparently identified, but the effects of thermal noise are shown to be significant. In particular we show experimental data that we interpret a...
The first archaic Homo from Taiwan.
Chang, Chun-Hsiang; Kaifu, Yousuke; Takai, Masanaru; Kono, Reiko T; Grün, Rainer; Matsu'ura, Shuji; Kinsley, Les; Lin, Liang-Kong
2015-01-01
Recent studies of an increasing number of hominin fossils highlight regional and chronological diversities of archaic Homo in the Pleistocene of eastern Asia. However, such a realization is still based on limited geographical occurrences mainly from Indonesia, China and Russian Altai. Here we describe a newly discovered archaic Homo mandible from Taiwan (Penghu 1), which further increases the diversity of Pleistocene Asian hominins. Penghu 1 revealed an unexpectedly late survival (younger than 450 but most likely 190-10 thousand years ago) of robust, apparently primitive dentognathic morphology in the periphery of the continent, which is unknown among the penecontemporaneous fossil records from other regions of Asia except for the mid-Middle Pleistocene Homo from Hexian, Eastern China. Such patterns of geographic trait distribution cannot be simply explained by clinal geographic variation of Homo erectus between northern China and Java, and suggests survival of multiple evolutionary lineages among archaic hominins before the arrival of modern humans in the region. PMID:25625212
Authenticity and autochthonous traditions in archaic and Hellenistic poetry
Klooster, Julia
2016-01-01
J.J.H. Klooster, ‘Authenticity and autochthonous traditions in archaic and Hellenistic poetry’. In E. Bakker (ed): Authorship, Authority and Authenticity in Archaic and Classical Greek Song. Proceedings of the Network for the Study of Archaic and Classical Greek Song, Vol. 2, Leiden: Brill
The evolution of two archaic Sicilian poleis
De Angelis, Franco.
1996-01-01
This study attempts to revive T.J. Dunbabin's multi-dimensional approach to the history of Early Iron Age Sicily in The Western Greeks (Oxford 1948). Dunbabin recognised that archaic Sicily had no real history, and that any historical account involved combining the very scant documentary record with the fuller and ever-growing body of archaeological evidence to produce a framework for writing social and economic history. These innovative methods ended with Dunbabin, however: t...
Space in archaic Greek lyric: city, countryside and sea
Heirman, Jo
2012-01-01
From the end of the twentieth century onwards space has become a 'hot topic' in literary studies. This thesis contributes to the spatial turn by focusing on space in archaic Greek lyric (7th-5th c bc). A theoretical framework inspired by narratology, phenomenology and metaphor theory is applied to archaic lyric poems in which city, countryside and sea are of importance. Heirman argues that space is predominantly symbolic: the city is a political or an erotic metaphor, the countryside an eroti...
Banerjee, S; Grebogi, C; Banerjee, Soumitro; Yorke, James A.; Grebogi, Celso
1998-01-01
It has been proposed to make practical use of chaos in communication, in enhancing mixing in chemical processes and in spreading the spectrum of switch-mode power suppies to avoid electromagnetic interference. It is however known that for most smooth chaotic systems, there is a dense set of periodic windows for any range of parameter values. Therefore in practical systems working in chaotic mode, slight inadvertent fluctuation of a parameter may take the system out of chaos. We say a chaotic attractor is robust if, for its parameter values there exists a neighborhood in the parameter space with no periodic attractor and the chaotic attractor is unique in that neighborhood. In this paper we show that robust chaos can occur in piecewise smooth systems and obtain the conditions of its occurrence. We illustrate this phenomenon with a practical example from electrical engineering.
Waelbroeck, H
1999-01-01
We propose a theory of deterministic chaos for discrete systems, based on their representations in symbolic history spaces Ømega. These are spaces of semi-infinite sequences, as the one-sided shift spaces, but endowed with a more general topology which we call a semicausal topology. We show that define metrical properties, including the correlation dimension of the attractor. Examples are considered: Asymmetric neural networks and random cellular automata are not chaotic. A neural network model with memory, on the other hand, does appear to be an example of discrete chaos.
Space in archaic Greek lyric: city, countryside and sea
Jong, de, J.; Heirman, J.G.M.
2012-01-01
From the end of the twentieth century onwards space has become a ‘hot topic’ in literary studies. This thesis contributes to the spatial turn by focusing on space in archaic Greek lyric (7th-5th C BC). A theoretical framework inspired by narratology, phenomenology and metaphor theory is applied to archaic lyric poems in which city, countryside and sea are of importance. Heirman argues that space is predominantly symbolic: the city is a political or an erotic metaphor, the countryside an eroti...
Space in Archaic Greek Lyric : City, Countryside and Sea
Heirman, Jo
2012-01-01
From the end of the twentieth century onwards space has become a 'hot topic' in literary studies. This thesis contributes to the spatial turn by focusing on space in archaic Greek lyric (7th-5th c bc). A theoretical framework inspired by narratology, phenomenology and metaphor theory is applied to a
Space in archaic Greek lyric: city, countryside and sea
J.G.M. Heirman
2012-01-01
From the end of the twentieth century onwards space has become a ‘hot topic’ in literary studies. This thesis contributes to the spatial turn by focusing on space in archaic Greek lyric (7th-5th C BC). A theoretical framework inspired by narratology, phenomenology and metaphor theory is applied to a
Casati, Giulio; Chirikov, Boris
2006-11-01
Preface; Acknowledgments; Introduction: 1. The legacy of chaos in quantum mechanics G. Casati and B. V. Chirikov; Part I. Classical Chaos and Quantum Localization: 2. Stochastic behaviour of a quantum pendulum under a periodic perturbation G. Casati, B. V. Chirikov, F. M. Izrailev and J. Ford; 3. Quantum dynamics of a nonintegrable system D. R. Grempel, R. E. Prange and S. E. Fishman; 4. Excitation of molecular rotation by periodic microwave pulses. A testing ground for Anderson localization R. Blümel, S. Fishman and U. Smilansky; 5. Localization of diffusive excitation in multi-level systems D. K. Shepelyansky; 6. Classical and quantum chaos for a kicked top F. Haake, M. Kus and R. Scharf; 7. Self-similarity in quantum dynamics L. E. Reichl and L. Haoming; 8. Time irreversibility of classically chaotic quantum dynamics K. Ikeda; 9. Effect of noise on time-dependent quantum chaos E. Ott, T. M. Antonsen Jr and J. D. Hanson; 10. Dynamical localization, dissipation and noise R. F. Graham; 11. Maximum entropy models and quantum transmission in disordered systems J.-L. Pichard and M. Sanquer; 12. Solid state 'atoms' in intense oscillating fields M. S. Sherwin; Part II. Atoms in Strong Fields: 13. Localization of classically chaotic diffusion for hydrogen atoms in microwave fields J. E. Bayfield, G. Casati, I. Guarneri and D. W. Sokol; 14. Inhibition of quantum transport due to 'scars' of unstable periodic orbits R. V. Jensen, M. M. Sanders, M. Saraceno and B. Sundaram; 15. Rubidium Rydberg atoms in strong fields G. Benson, G. Raithel and H. Walther; 16. Diamagnetic Rydberg atom: confrontation of calculated and observed spectra C.-H. Iu, G. R. Welch, M. M. Kash, D. Kleppner, D. Delande and J. C. Gay; 17. Semiclassical approximation for the quantum states of a hydrogen atom in a magnetic field near the ionization limit M. Y. Kuchiev and O. P. Sushkov; 18. The semiclassical helium atom D. Wintgen, K. Richter and G. Tanner; 19. Stretched helium: a model for quantum chaos
Peccati, Giovanni
2011-01-01
The concept of Wiener chaos generalizes to an infinite-dimensional setting the properties of orthogonal polynomials associated with probability distributions on the real line. It plays a crucial role in modern probability theory, with applications ranging from Malliavin calculus to stochastic differential equations and from probabilistic approximations to mathematical finance. This book is concerned with combinatorial structures arising from the study of chaotic random variables related to infinitely divisible random measures. The combinatorial structures involved are those of partitions of fi
Stochastic Chaos with Its Control and Synchronization
Institute of Scientific and Technical Information of China (English)
Zhang Ying; Xu Wei; Zhang Tianshu; Yang Xiaoli; Wu Cunli; Fang Tong
2008-01-01
The discovery of chaos in the sixties of last century was a breakthrough in concept,revealing the truth that some disorder behavior, called chaos, could happen even in a deterministic nonlinear system under barely deterministic disturbance. After a series of serious studies, people begin to acknowledge that chaos is a specific type of steady state motion other than the conventional periodic and quasi-periodic ones, featuring a sensitive dependence on initial conditions, resulting from the intrinsic randomness of a nonlinear system itself. In fact, chaos is a collective phenomenon consisting of massive individual chaotic responses, corresponding to different initial conditions in phase space. Any two adjacent individual chaotic responses repel each other, thus causing not only the sensitive dependence on initial conditions but also the existence of at least one positive top Lyapunov exponent (TLE) for chaos. Meanwhile, all the sample responses share one common invariant set on the Poincaré map, called chaotic attractor,which every sample response visits from time to time ergodically. So far, the existence of at least one positive TLE is a commonly acknowledged remarkable feature of chaos. We know that there are various forms of uncertainties in the real world. In theoretical studies, people often use stochastic models to describe these uncertainties, such as random variables or random processes.Systems with random variables as their parameters or with random processes as their excitations are often called stochastic systems. No doubt, chaotic phenomena also exist in stochastic systems, which we call stochastic chaos to distinguish it from deterministic chaos in the deterministic system. Stochastic chaos reflects not only the intrinsic randomness of the nonlinear system but also the external random effects of the random parameter or the random excitation.Hence, stochastic chaos is also a collective massive phenomenon, corresponding not only to different initial
Huwe, Terence K.
2009-01-01
"Embracing the chaos" is an ongoing challenge for librarians. Embracing the chaos means librarians must have a plan for responding to the flood of new products, widgets, web tools, and gizmos that students use daily. In this article, the author argues that library instruction and access services have been grappling with that chaos with some degree…
Some chaotic features of intrinsically coupled Josephson junctions
Energy Technology Data Exchange (ETDEWEB)
Kolahchi, M.R., E-mail: kolahchi@iasbs.ac.ir [Institute for Advanced Studies in Basic Sciences, Zanjan 45195-1159 (Iran, Islamic Republic of); Shukrinov, Yu.M. [BLTP, JINR, Dubna, Moscow Region 141980 (Russian Federation); Max-Planck-Institute for the Physics of Complex Systems, 01187 Dresden (Germany); Hamdipour, M. [Institute for Advanced Studies in Basic Sciences, Zanjan 45195-1159 (Iran, Islamic Republic of); BLTP, JINR, Dubna, Moscow Region 141980 (Russian Federation); Botha, A.E. [Department of Physics, University of South Africa, P.O. Box 392, Pretoria 0003 (South Africa); Suzuki, M. [Photonics and Electronics Science and Engineering Center and Department of Electronic Science and Engineering, Kyoto University, Kyoto 615-8510 (Japan)
2013-08-15
Highlights: ► Intrinsically coupled Josephson junctions model a high-T{sub c} superconductor. ► Intrinsically coupled Josephson junctions can act as a chaotic nonlinear system. ► Chaos could be due to resonance overlap. ► Avoiding parameters that lead to chaos is important for the design of resonators. -- Abstract: We look for chaos in an intrinsically coupled system of Josephson junctions. This study has direct applications for the high-T{sub c} resonators which require coherence amongst the junctions.
Universal quantification for deterministic chaos in dynamical systems
Selvam, A. Mary
2000-01-01
A cell dynamical system model for deterministic chaos enables precise quantification of the round-off error growth,i.e., deterministic chaos in digital computer realizations of mathematical models of continuum dynamical systems. The model predicts the following: (a) The phase space trajectory (strange attractor) when resolved as a function of the computer accuracy has intrinsic logarithmic spiral curvature with the quasiperiodic Penrose tiling pattern for the internal structure. (b) The unive...
Manifestation of resonance-related chaos in coupled Josephson junctions
Energy Technology Data Exchange (ETDEWEB)
Shukrinov, Yu.M. [BLTP, JINR, Dubna, Moscow Region, 141980 (Russian Federation); Hamdipour, M. [BLTP, JINR, Dubna, Moscow Region, 141980 (Russian Federation); Institute for Advanced Studies in Basic Sciences, P.O. Box 45195-1159, Zanjan (Iran, Islamic Republic of); Kolahchi, M.R. [Institute for Advanced Studies in Basic Sciences, P.O. Box 45195-1159, Zanjan (Iran, Islamic Republic of); Botha, A.E., E-mail: bothaae@unisa.ac.za [Department of Physics, University of South Africa, P.O. Box 392, Pretoria 0003 (South Africa); Suzuki, M. [Photonics and Electronics Science and Engineering Center and Department of Electronic Science and Engineering, Kyoto University, Kyoto 615-8510 (Japan)
2012-11-01
Manifestation of chaos in the temporal dependence of the electric charge is demonstrated through the calculation of the maximal Lyapunov exponent, phase–charge and charge–charge Lissajous diagrams and correlation functions. It is found that the number of junctions in the stack strongly influences the fine structure in the current–voltage characteristics and a strong proximity effect results from the nonperiodic boundary conditions. The observed resonance-related chaos exhibits intermittency. The criteria for a breakpoint region with no chaos are obtained. Such criteria could clarify recent experimental observations of variations in the power output from intrinsic Josephson junctions in high temperature superconductors.
Manifestation of resonance-related chaos in coupled Josephson junctions
Shukrinov, Yu. M.; Hamdipour, M.; Kolahchi, M. R.; Botha, A. E.; Suzuki, M.
2012-11-01
Manifestation of chaos in the temporal dependence of the electric charge is demonstrated through the calculation of the maximal Lyapunov exponent, phase-charge and charge-charge Lissajous diagrams and correlation functions. It is found that the number of junctions in the stack strongly influences the fine structure in the current-voltage characteristics and a strong proximity effect results from the nonperiodic boundary conditions. The observed resonance-related chaos exhibits intermittency. The criteria for a breakpoint region with no chaos are obtained. Such criteria could clarify recent experimental observations of variations in the power output from intrinsic Josephson junctions in high temperature superconductors.
Erçetin, Şefika; Tekin, Ali
2014-01-01
The present work investigates global politics and political implications of social science and management with the aid of the latest complexity and chaos theories. Until now, deterministic chaos and nonlinear analysis have not been a focal point in this area of research. This book remedies this deficiency by utilizing these methods in the analysis of the subject matter. The authors provide the reader a detailed analysis on politics and its associated applications with the help of chaos theory, in a single edited volume.
Quantum Chaos and Statistical Mechanics
Srednicki, Mark
1994-01-01
We briefly review the well known connection between classical chaos and classical statistical mechanics, and the recently discovered connection between quantum chaos and quantum statistical mechanics.
Understanding Chaos via Nuclei
Cejnar, Pavel; Stránský, Pavel
2014-01-01
We use two models of nuclear collective dynamics - the geometric collective model and the interacting boson model - to illustrate principles of classical and quantum chaos. We propose these models as a suitable testing ground for further elaborations of the general theory of chaos in both classical and quantum domains.
Harnessing quantum transport by transient chaos.
Yang, Rui; Huang, Liang; Lai, Ying-Cheng; Grebogi, Celso; Pecora, Louis M
2013-03-01
Chaos has long been recognized to be generally advantageous from the perspective of control. In particular, the infinite number of unstable periodic orbits embedded in a chaotic set and the intrinsically sensitive dependence on initial conditions imply that a chaotic system can be controlled to a desirable state by using small perturbations. Investigation of chaos control, however, was largely limited to nonlinear dynamical systems in the classical realm. In this paper, we show that chaos may be used to modulate or harness quantum mechanical systems. To be concrete, we focus on quantum transport through nanostructures, a problem of considerable interest in nanoscience, where a key feature is conductance fluctuations. We articulate and demonstrate that chaos, more specifically transient chaos, can be effective in modulating the conductance-fluctuation patterns. Experimentally, this can be achieved by applying an external gate voltage in a device of suitable geometry to generate classically inaccessible potential barriers. Adjusting the gate voltage allows the characteristics of the dynamical invariant set responsible for transient chaos to be varied in a desirable manner which, in turn, can induce continuous changes in the statistical characteristics of the quantum conductance-fluctuation pattern. To understand the physical mechanism of our scheme, we develop a theory based on analyzing the spectrum of the generalized non-Hermitian Hamiltonian that includes the effect of leads, or electronic waveguides, as self-energy terms. As the escape rate of the underlying non-attracting chaotic set is increased, the imaginary part of the complex eigenenergy becomes increasingly large so that pointer states are more difficult to form, making smoother the conductance-fluctuation pattern.
Maldacena, Juan; Stanford, Douglas
2015-01-01
We conjecture a sharp bound on the rate of growth of chaos in thermal quantum systems with a large number of degrees of freedom. Chaos can be diagnosed using an out-of-time-order correlation function closely related to the commutator of operators separated in time. We conjecture that the influence of chaos on this correlator can develop no faster than exponentially, with Lyapunov exponent $\\lambda_L \\le 2 \\pi k_B T/\\hbar$. We give a precise mathematical argument, based on plausible physical assumptions, establishing this conjecture.
Chaos applications in telecommunications
Stavroulakis, Peter
2005-01-01
IntroductionPeter StavroulakisChaotic Signal Generation and Transmission Antonio Cândido Faleiros,Waldecir João Perrella,TâniaNunes Rabello,Adalberto Sampaio Santos, andNeiYoshihiro SomaChaotic Transceiver Design Arthur Fleming-DahlChaos-Based Modulation and DemodulationTechniques Francis C.M. Lau and Chi K. TseA Chaos Approach to Asynchronous DS-CDMASystems S. Callegari, G. Mazzini, R. Rovatti, and G. SettiChannel Equalization in Chaotic CommunicationSystems Mahmut CiftciOptical Communications using ChaoticTechniques Gregory D. VanWiggerenAPPENDIX AFundamental Concepts of the Theory ofChaos a
Exploiting chaos for applications
Energy Technology Data Exchange (ETDEWEB)
Ditto, William L., E-mail: wditto@hawaii.edu [Department of Physics and Astronomy, University of Hawaii at Mānoa, Honolulu, Hawaii 96822 (United States); Sinha, Sudeshna, E-mail: sudeshna@iisermohali.ac.in [Indian Institute of Science Education and Research (IISER), Mohali, Knowledge City, Sector 81, SAS Nagar, PO Manauli 140306, Punjab (India)
2015-09-15
We discuss how understanding the nature of chaotic dynamics allows us to control these systems. A controlled chaotic system can then serve as a versatile pattern generator that can be used for a range of application. Specifically, we will discuss the application of controlled chaos to the design of novel computational paradigms. Thus, we present an illustrative research arc, starting with ideas of control, based on the general understanding of chaos, moving over to applications that influence the course of building better devices.
Exploiting chaos for applications
International Nuclear Information System (INIS)
We discuss how understanding the nature of chaotic dynamics allows us to control these systems. A controlled chaotic system can then serve as a versatile pattern generator that can be used for a range of application. Specifically, we will discuss the application of controlled chaos to the design of novel computational paradigms. Thus, we present an illustrative research arc, starting with ideas of control, based on the general understanding of chaos, moving over to applications that influence the course of building better devices
Hosur, Pavan; Qi, Xiao-Liang; Roberts, Daniel; Yoshida, Beni(Institute for Quantum Information & Matter and Walter Burke Institute for Theoretical Physics, California Institute of Technology, 1200 E. California Blvd., Pasadena, CA, 91125, U.S.A.)
2016-01-01
We study chaos and scrambling in unitary channels by considering their entanglement properties as states. Using out-of-time-order correlation functions to diagnose chaos, we characterize the ability of a channel to process quantum information. We show that the generic decay of such correlators implies that any input subsystem must have near vanishing mutual information with almost all partitions of the output. Additionally, we propose the negativity of the tripartite information of the channe...
Fractal Patterns and Chaos Games
Devaney, Robert L.
2004-01-01
Teachers incorporate the chaos game and the concept of a fractal into various areas of the algebra and geometry curriculum. The chaos game approach to fractals provides teachers with an opportunity to help students comprehend the geometry of affine transformations.
DEFF Research Database (Denmark)
Orlando, Ludovic Antoine Alexandre
2014-01-01
By combining state-of-the-art approaches in ancient genomics, Meyer and co-workers have reconstructed the mitochondrial sequence of an archaic hominin that lived at Sierra de Atapuerca, Spain about 400,000 years ago. This achievement follows recent advances in molecular anthropology that delivered...
Dissipative structures and chaos
Mori, Hazime
1998-01-01
This monograph consists of two parts and gives an approach to the physics of open nonequilibrium systems. Part I derives the phenomena of dissipative structures on the basis of reduced evolution equations and includes Bénard convection and Belousov-Zhabotinskii chemical reactions. Part II discusses the physics and structures of chaos. While presenting a construction of the statistical physics of chaos, the authors unify the geometrical and statistical descriptions of dynamical systems. The shape of chaotic attractors is characterized, as are the mixing and diffusion of chaotic orbits and the fluctuation of energy dissipation exhibited by chaotic systems.
Deterministic chaos an introduction
Schuster, Heinz Georg
2005-01-01
A new edition of this well-established monograph, this volume provides a comprehensive overview over the still fascinating field of chaos research. The authors include recent developments such as systems with restricted degrees of freedom but put also a strong emphasis on the mathematical foundations. Partly illustrated in color, this fourth edition features new sections from applied nonlinear science, like control of chaos, synchronisation of nonlinear systems, and turbulence, as well as recent theoretical concepts like strange nonchaotic attractors, on-off intermittency and spatio-temporal chaotic motion
Directory of Open Access Journals (Sweden)
B. Buti
1999-01-01
Full Text Available A nonlinear wave, in general, is equivalent to a nonlinear dynamical system, which exhibits the phenomena of chaos. By means of techniques of nonlinear dynamical systems, we have investigated the conditions under which nonlinear Alfvén waves and lower-hybrid waves can become chaotic. The role of heavy ions, in controlling the chaos in magnetoplasmas, is examined. Chaotic routes to Alfvénic turbulence, with k-1 spectra, are observed in case of externally driven nonlinear Alfvén waves. Anomalous heating and particle acceleration resulting from chaotic fields, generated by lower-hybrid waves, are briefly outlined.
Akhmet, Marat; Fen, Mehmet Onur
2012-01-01
Morphogenesis, as it is understood in a wide sense by Ren\\'e Thom, is considered for various types of chaos. That is, those, obtained by period-doubling cascade, Devaney's and Li-Yorke chaos. Moreover, in discussion form we consider inheritance of intermittency, the double-scroll Chua's attractor and quasiperiodical motions as a possible skeleton of a chaotic attractor. To make our introduction of the paper more clear, we have to say that one may consider other various accompanying concepts o...
R. Kříž
2011-01-01
This paper presents an analysis of GDP and finds chaos in GDP. I tried to find a nonlinear lower-dimensional discrete dynamic macroeconomic model that would characterize GDP. This model is represented by a set of differential equations. I have used the Mathematica and MS Excel programs for the analysis.
Directory of Open Access Journals (Sweden)
Kratochvíl C.
2007-10-01
Full Text Available The purpose of this article is to provide an elementary introduction to the subject of chaos in the electromechanical drive systems. In this article, we explore chaotic solutions of maps and continuous time systems. These solutions are also bounded like equilibrium, periodic and quasiperiodic solutions.
Inverse anticipating chaos synchronization.
Shahverdiev, E M; Sivaprakasam, S; Shore, K A
2002-07-01
We derive conditions for achieving inverse anticipating synchronization where a driven time-delay chaotic system synchronizes to the inverse future state of the driver. The significance of inverse anticipating chaos in delineating synchronization regimes in time-delay systems is elucidated. The concept is extended to cascaded time-delay systems.
DEFF Research Database (Denmark)
Lykke, Marianne; Lund, Haakon; Skov, Mette
2016-01-01
CHAOS (Cultural Heritage Archive Open System) provides streaming access to more than 500.000 broad-casts by the Danish Broadcast Corporation from 1931 and onwards. The archive is part of the LARM project with the purpose of enabling researchers to search, annotate, and interact with recordings. T...
Chaos induced by coupling between Josephson junctions
Shukrinov, Yu. M.; Azemtsa-Donfack, H.; Botha, A. E.
2015-02-01
It is found that, in a stack of intrinsic Josephson junctions in layered high temperature superconductors under external electromagnetic radiation, the chaotic features are triggered by interjunction coupling, i.e., the coupling between different junctions in the stack. While the radiation is well known to produce chaotic effects in the single junction, the effect of interjunction coupling is fundamentally different and it can lead to the onset of chaos via a different route to that of the single junction. A precise numerical study of the phase dynamics of intrinsic Josephson junctions, as described by the CCJJ+DC model, is performed. We demonstrate the charging of superconducting layers, in a bias current interval corresponding to a Shapiro step subharmonic, due to the creation of a longitudinal plasma wave along the stack of junctions. With increase in radiation amplitude chaotic behavior sets in. The chaotic features of the coupled Josephson junctions are analyzed by calculations of the Lyapunov exponents. We compare results for a stack of junctions to the case of a single junction and prove that the observed chaos is induced by the coupling between the junctions. The use of Shapiro step subharmonics may allow longitudinal plasma waves to be excited at low radiation power.
High-dimensional chaos from self-sustained collisions of solitons
International Nuclear Information System (INIS)
We experimentally demonstrate chaos generation based on collisions of electrical solitons on a nonlinear transmission line. The nonlinear line creates solitons, and an amplifier connected to it provides gain to these solitons for their self-excitation and self-sustenance. Critically, the amplifier also provides a mechanism to enable and intensify collisions among solitons. These collisional interactions are of intrinsically nonlinear nature, modulating the phase and amplitude of solitons, thus causing chaos. This chaos generated by the exploitation of the nonlinear wave phenomena is inherently high-dimensional, which we also demonstrate.
Phase Desynchronization as a Mechanism for Transitions to High-Dimensional Chaos
Institute of Scientific and Technical Information of China (English)
ZHENG ZhiGang; HU Gang
2001-01-01
Phase is an important degree of freedom in studies of chaotic oscillations. Phase coherence and localization in coupled chaotic elements are studied. It is shown that phase desynchronization is a key mechanism responsible for the transitions from low- to high-dimensional chaos. The route from low-dimensional chaos to high-dimensional toroidal chaos is accompanied by a cascade of phase desynchronizations. Phase synchronization tree is adopted to exhibit the entrainment process. This bifurcation tree implies an intrinsic cascade of order embedded in irregular motions.``
Fuzzy controller based on chaos optimal design and its application
Institute of Scientific and Technical Information of China (English)
邹恩; 李祥飞; 张泰山
2004-01-01
In order to overcome difficulty of tuning parameters of fuzzy controller, a chaos optimal design method based on annealing strategy is proposed. First, apply the chaotic variables to search for parameters of fuzzy controller, and transform the optimal variables into chaotic variables by carrier-wave method. Making use of the intrinsic stochastic property and ergodicity of chaos movement to escape from the local minimum and direct optimization searching within global range, an approximate global optimal solution is obtained. Then, the chaos local searching and optimization based on annealing strategy are cited, the parameters are optimized again within the limits of the approximate global optimal solution, the optimization is realized by means of combination of global and partial chaos searching, which can converge quickly to global optimal value. Finally, the third order system and discrete nonlinear system are simulated and compared with traditional method of fuzzy control. The results show that the new chaos optimal design method is superior to fuzzy control method, and that the control results are of high precision, with no overshoot and fast response.
Energy Technology Data Exchange (ETDEWEB)
Tél, Tamás [Institute for Theoretical Physics, Eötvös University, and MTA-ELTE Theoretical Physics Research Group, Pázmány P. s. 1/A, Budapest H-1117 (Hungary)
2015-09-15
We intend to show that transient chaos is a very appealing, but still not widely appreciated, subfield of nonlinear dynamics. Besides flashing its basic properties and giving a brief overview of the many applications, a few recent transient-chaos-related subjects are introduced in some detail. These include the dynamics of decision making, dispersion, and sedimentation of volcanic ash, doubly transient chaos of undriven autonomous mechanical systems, and a dynamical systems approach to energy absorption or explosion.
Tél, Tamás
2015-09-01
We intend to show that transient chaos is a very appealing, but still not widely appreciated, subfield of nonlinear dynamics. Besides flashing its basic properties and giving a brief overview of the many applications, a few recent transient-chaos-related subjects are introduced in some detail. These include the dynamics of decision making, dispersion, and sedimentation of volcanic ash, doubly transient chaos of undriven autonomous mechanical systems, and a dynamical systems approach to energy absorption or explosion.
Matsushita, Raul; Gleria, Iram; Figueiredo, Annibal; Da Silva, Sergio
2007-05-01
The yuan-dollar returns prior to the 2005 revaluation show a Sierpinski triangle in an iterated function system clumpiness test. Yet the fractal vanishes after the revaluation. The Sierpinski commonly emerges in the chaos game, where randomness coexists with deterministic rules (M.F. Barnsley, Fractals Everywhere, Academic Press, San Diego, 1988; H.O. Peitgen, H. Jurgens, D. Saupe, Chaos and Fractals: New Frontiers of Science, Springer, New York, 1992). Here, it is explained by the yuan's pegs to the US dollar, which made more than half of the data points close to zero. Extra data from the Brazilian and Argentine experiences do confirm that the fractal emerges whenever exchange rate pegs are kept for too long.
Chaos detection and predictability
Gottwald, Georg; Laskar, Jacques
2016-01-01
Distinguishing chaoticity from regularity in deterministic dynamical systems and specifying the subspace of the phase space in which instabilities are expected to occur is of utmost importance in as disparate areas as astronomy, particle physics and climate dynamics. To address these issues there exists a plethora of methods for chaos detection and predictability. The most commonly employed technique for investigating chaotic dynamics, i.e. the computation of Lyapunov exponents, however, may suffer a number of problems and drawbacks, for example when applied to noisy experimental data. In the last two decades, several novel methods have been developed for the fast and reliable determination of the regular or chaotic nature of orbits, aimed at overcoming the shortcomings of more traditional techniques. This set of lecture notes and tutorial reviews serves as an introduction to and overview of modern chaos detection and predictability techniques for graduate students and non-specialists. The book cover...
Marklof, J
2005-01-01
The central objective in the study of quantum chaos is to characterize universal properties of quantum systems that reflect the regular or chaotic features of the underlying classical dynamics. Most developments of the past 25 years have been influenced by the pioneering models on statistical properties of eigenstates (Berry 1977) and energy levels (Berry and Tabor 1977; Bohigas, Giannoni and Schmit 1984). Arithmetic quantum chaos (AQC) refers to the investigation of quantum system with additional arithmetic structures that allow a significantly more extensive analysis than is generally possible. On the other hand, the special number-theoretic features also render these systems non-generic, and thus some of the expected universal phenomena fail to emerge. Important examples of such systems include the modular surface and linear automorphisms of tori (`cat maps') which will be described below.
Hosur, Pavan; Roberts, Daniel A; Yoshida, Beni
2015-01-01
We study chaos and scrambling in unitary channels by considering their entanglement properties as states. Using out-of-time-order correlation functions to diagnose chaos, we characterize the ability of a channel to process quantum information. We show that the generic decay of such correlators implies that any input subsystem must have near vanishing mutual information with almost all partitions of the output. Additionally, we propose the negativity of the tripartite information of the channel as a general diagnostic of scrambling. This measures the delocalization of information and is closely related to the decay of out-of-time-order correlators. We back up our results with numerics in two non-integrable models and analytic results in a perfect tensor network model of chaotic time evolution. These results show that the butterfly effect in quantum systems implies the information-theoretic definition of scrambling.
Wild Goat style ceramics at Troy and the impact of Archaic period colonisation on the Troad
Aslan, Carolyn C.; Pernicka, Ernst
2013-01-01
The establishment of colonies along the Hellespont by inhabitants of Ionia, Athens and Lesbos is well-known from historical texts. Recently, stratified contexts at Troy as well as other surveys and excavations have yielded new information about the chronology and material markers of Archaic period settlements in the Troad and the Gallipoli peninsula. The archaeological evidence for colonisation in this region is not clearly seen until the late seventh to early sixth century BC when there is a...
Martingales, Nonlinearity, and Chaos
Barnett, William A.; Apostolos Serletis
1998-01-01
In this article we provide a review of the literature with respect to the efficient markets hypothesis and chaos. In doing so, we contrast the martingale behavior of asset prices to nonlinear chaotic dynamics, discuss some recent techniques used in distinguishing between probabilistic and deterministic behavior in asset prices, and report some evidence. Moreover, we look at the controversies that have arisen about the available tests and results, and raise the issue of whether dynamical syste...
Earnshow, R; Jones, H
1991-01-01
This volume is based upon the presentations made at an international conference in London on the subject of 'Fractals and Chaos'. The objective of the conference was to bring together some of the leading practitioners and exponents in the overlapping fields of fractal geometry and chaos theory, with a view to exploring some of the relationships between the two domains. Based on this initial conference and subsequent exchanges between the editors and the authors, revised and updated papers were produced. These papers are contained in the present volume. We thank all those who contributed to this effort by way of planning and organisation, and also all those who helped in the production of this volume. In particular, we wish to express our appreciation to Gerhard Rossbach, Computer Science Editor, Craig Van Dyck, Production Director, and Nancy A. Rogers, who did the typesetting. A. J. Crilly R. A. Earnshaw H. Jones 1 March 1990 Introduction Fractals and Chaos The word 'fractal' was coined by Benoit Mandelbrot i...
Chaos Criminology: A critical analysis
McCarthy, Adrienne L.
There has been a push since the early 1980's for a paradigm shift in criminology from a Newtonian-based ontology to one of quantum physics. Primarily this effort has taken the form of integrating Chaos Theory into Criminology into what this thesis calls 'Chaos Criminology'. However, with the melding of any two fields, terms and concepts need to be translated properly, which has yet to be done. In addition to proving a translation between fields, this thesis also uses a set of criteria to evaluate the effectiveness of the current use of Chaos Theory in Criminology. While the results of the theory evaluation reveal that the current Chaos Criminology work is severely lacking and in need of development, there is some promise in the development of Marx's dialectical materialism with Chaos Theory.
Institute of Scientific and Technical Information of China (English)
方锦清; 罗晓曙; 陈关荣; 翁甲强
2001-01-01
Beam halo-chaos is essentially a complex spatiotemporal chaotic motion in a periodic-focusing channel of a highpower linear proton accelerator. The controllability condition for beam halo-chaos is analysed qualitatively. A special nonlinear control method, i.e. the wavelet-based function feedback, is proposed for controlling beam halochaos. Particle-in-cell simulations are used to explore the nature of halo-chaos formation, which has shown that the beam hMo-chaos is suppressed effectively after using nonlinear control for the proton beam with an initial full Gaussian distribution. The halo intensity factor Hav is reduced from 14%o to zero, and the other statistical physical quantities of beam halo-chaos are more than doubly reduced. The potential applications of such nonlinear control in experiments are briefly pointed out.
Transition to Chaos in Random Neuronal Networks
Kadmon, Jonathan; Sompolinsky, Haim
2015-10-01
Firing patterns in the central nervous system often exhibit strong temporal irregularity and considerable heterogeneity in time-averaged response properties. Previous studies suggested that these properties are the outcome of the intrinsic chaotic dynamics of the neural circuits. Indeed, simplified rate-based neuronal networks with synaptic connections drawn from Gaussian distribution and sigmoidal nonlinearity are known to exhibit chaotic dynamics when the synaptic gain (i.e., connection variance) is sufficiently large. In the limit of an infinitely large network, there is a sharp transition from a fixed point to chaos, as the synaptic gain reaches a critical value. Near the onset, chaotic fluctuations are slow, analogous to the ubiquitous, slow irregular fluctuations observed in the firing rates of many cortical circuits. However, the existence of a transition from a fixed point to chaos in neuronal circuit models with more realistic architectures and firing dynamics has not been established. In this work, we investigate rate-based dynamics of neuronal circuits composed of several subpopulations with randomly diluted connections. Nonzero connections are either positive for excitatory neurons or negative for inhibitory ones, while single neuron output is strictly positive with output rates rising as a power law above threshold, in line with known constraints in many biological systems. Using dynamic mean field theory, we find the phase diagram depicting the regimes of stable fixed-point, unstable-dynamic, and chaotic-rate fluctuations. We focus on the latter and characterize the properties of systems near this transition. We show that dilute excitatory-inhibitory architectures exhibit the same onset to chaos as the single population with Gaussian connectivity. In these architectures, the large mean excitatory and inhibitory inputs dynamically balance each other, amplifying the effect of the residual fluctuations. Importantly, the existence of a transition to chaos
Dembiński, S. T.; Makowski, A. J.; Pepłowski, P.
1993-02-01
We report for the first time quantum calculations for the so-called bouncer model, the classical analog of which is well known to manifest a chaotic behavior. Three versions of our model are fully tractable quantum mechanically and are potentially a rich source of data for establishing properties of a quantum system of which the classical mechanics can be chaotic. Among the results presented here, consequences of the varying bandwidth of infinite-dimensional transition matrices on the use of the correspondence between classical chaos and non-Poissonian quasienergy statistics are discussed.
An archaic crested plesiosaur in opal from the Lower Cretaceous high-latitude deposits of Australia
Kear, Benjamin P.; Schroeder, Natalie I; Michael S Y Lee
2006-01-01
Umoonasaurus demoscyllus gen. et sp. nov. is a new small-bodied (approx. 2.5 m) pliosauroid plesiosaur from the Lower Cretaceous (Aptian–Albian) of southern Australia. It is represented by several partial skeletons (one with a near complete skull is the most complete opalized vertebrate fossil yet known), and is unique in having large crests on the skull midline and above the orbits. Umoonasaurus is surprisingly archaic despite its relatively late age (approx. 115 Myr ago)—being simultaneousl...
The Sacrificial Rituals of Greek Hero-Cults in the Archaic to the Early Hellenistic Period
Ekroth, Gunnel
2013-01-01
This study questions the traditional view of sacrifices in hero-cults during the Archaic to the early Hellenistic periods. The analysis of the epigraphical and literary evidence for sacrifices to heroes in these periods shows, contrary to the traditional notion, that the main ritual in hero-cults was a thysia at which the worshippers consumed the meat from the animal victim. A particular handling of the animal’s blood or a holocaust, rituals previously taken to be typical for heroes, can rare...
Chaos a very short introduction
Smith, Leonard
2007-01-01
Chaos: A Very Short Introduction shows that we all have an intuitive understanding of chaotic systems. It uses accessible maths and physics (replacing complex equations with simple examples like pendulums, railway lines, and tossing coins) to explain the theory, and points to numerous examples in philosophy and literature (Edgar Allen Poe, Chang-Tzu, and Arthur Conan Doyle) that illuminate the problems. The beauty of fractal patterns and their relation to chaos, as well as the history of chaos, and its uses in the real world and implications for the philosophy of science are all discussed in this Very Short Introduction.
Schmidt, Britney E.
2013-10-01
A critical question for the habitability of Europa remains: how does the ice shell work? The detection of shallow subsurface lenses below Europa’s chaos implies that the ice shell is recycled rapidly and that Europa may be currently active. While this is not the first time liquid water has been implicated for Europa, the location of these features combined with new perspective on their dynamics frames the question in a new way. Melt lenses are intriguing potential habitats. Moreover, their formation requires the existence of impurities within the upper ice shell that may be sources of energy for microorganisms. Geomorphic evidence also exists for hydraulic redistribution of fluids both vertically and horizontally through pores and fractures. This process, observed in terrestrial ice shelves, may preserve liquid water within the ice matrix over many kilometers from the source. Horizontal transport of material may produce interconnectivity between distinct regions of Europa, thus preserving habitable conditions within the ice over a longer duration. At a surface age of 40-90 Myr, with 25-50% covered by chaos terrain, Europa's resurfacing rate is very high and water likely plays a significant role. Because of the vigor of overturn implied by this new work, it is likely that surface and subsurface materials are well-mixed within the largest and deepest lenses, providing a mechanism for bringing oxidants and other surface contaminants to the deeper ice shell where it can reach the ocean by convective or compositional effects. The timescales over which large lenses refreeze are large compared to the timescales for vertical transport, while the timescales for smaller lenses are comparable to or shorter than convective timescales. Moreover, marine ice accretion at the bottom of the ice shell may be contributing to a compositional buoyancy engine that would change the makeup of the ice shell. From this point of view, we evaluate the habitability of Europa’s ice and
Directory of Open Access Journals (Sweden)
Akio Matsumoto
1997-01-01
Full Text Available This study augments the traditional linear cobweb model with lower and upper bounds for variations of output. Its purpose is to detect the relationship between the output constraints and the dynamics of the modified model. Due to the upper and lower bounds, a transitional function takes on a tilted z-profile having three piecewise segments with two turning points. It prevents the price (or quantity dynamics from explosive oscillations. This study demonstrates, by presenting numerical examples, that the modified cobweb model can generate various dynamics ranging from stable periodic cycles to ergodic chaos if a product of the marginal propensity to consume and the marginal product is greater than unity.
Mitchener, W Garrett; Nowak, Martin A
2004-04-01
Human language is a complex communication system with unlimited expressibility. Children spontaneously develop a native language by exposure to linguistic data from their speech community. Over historical time, languages change dramatically and unpredictably by accumulation of small changes and by interaction with other languages. We have previously developed a mathematical model for the acquisition and evolution of language in heterogeneous populations of speakers. This model is based on game dynamical equations with learning. Here, we show that simple examples of such equations can display complex limit cycles and chaos. Hence, language dynamical equations mimic complicated and unpredictable changes of languages over time. In terms of evolutionary game theory, we note that imperfect learning can induce chaotic switching among strict Nash equilibria.
Ercsey-Ravasz, Maria
2012-01-01
The mathematical structure of the widely popular Sudoku puzzles is akin to typical hard constraint satisfaction problems that lie at the heart of many applications, including protein folding and the general problem of finding the ground state of a glassy spin system. Via an exact mapping of Sudoku into a deterministic, continuous-time dynamical system, here we show that the difficulty of Sudoku translates into transient chaotic behavior exhibited by the dynamical system. In particular, we show that the escape rate $\\kappa$, an invariant characteristic of transient chaos, provides a single scalar measure of the puzzle's hardness, which correlates well with human difficulty level ratings. Accordingly, $\\eta = -\\log_{10}{\\kappa}$ can be used to define a "Richter"-type scale for puzzle hardness, with easy puzzles falling in the range $0 3$. To our best knowledge, there are no known puzzles with $\\eta > 4$.
DEFF Research Database (Denmark)
Lindberg, Erik
1996-01-01
Can we believe in the results of our circuit simulators ? Is it possible to distinguish between results due to numerical chaos and resultsdue to the eventual chaotic nature of our modelsof physical systems ?. Three experiments with SPICE are presented: (1) A "stable" active RCcircuit with poles...... in the right half plane. (2) "Chaotic" steady state behaviour of a non-chaotic dc power supply. (3) Analysis of a Colpitts oscillator with chaotic behaviour. In order to obtain reliable results from the SPICE simulators the users of these programs need insight not only in the use of the programs but also...... in the models of the circuits to be analyzed. If trimmed properly SPICE normally gives the correct result....
Wernecke, Hendrik; Gros, Claudius
2016-01-01
For a chaotic system pairs of initially close-by trajectories become eventually fully uncorrelated on the attracting set. This process of decorrelation is split into an initial decrease characterized by the maximal Lyapunov exponent and a subsequent diffusive process on the chaotic attractor causing the final loss of predictability. The time scales of both processes can be either of the same or of very different orders of magnitude. In the latter case the two trajectories linger within a finite but small distance (with respect to the overall size of the attractor) for exceedingly long times and therefore remain partially predictable. We introduce a 0-1 indicator for chaos capable of describing this scenario, arguing, in addition, that the chaotic closed braids found close to a period-doubling transition are generically partially predictable.
Quantum Instantons and Quantum Chaos
Jirari, H.; Kröger, H.; Luo, X. Q.; Moriarty, K. J. M.; Rubin, S. G.
1999-01-01
Based on a closed form expression for the path integral of quantum transition amplitudes, we suggest rigorous definitions of both, quantum instantons and quantum chaos. As an example we compute the quantum instanton of the double well potential.
Chaos and complexity by design
Roberts, Daniel A
2016-01-01
We study the relationship between quantum chaos and pseudorandomness by developing probes of unitary design. A natural probe of randomness is the "frame potential," which is minimized by unitary $k$-designs and measures the $2$-norm distance between the Haar random unitary ensemble and another ensemble. A natural probe of quantum chaos is out-of-time-order (OTO) four-point correlation functions. We show that the norm squared of a generalization of out-of-time-order $2k$-point correlators is proportional to the $k$th frame potential, providing a quantitative connection between chaos and pseudorandomness. Additionally, we prove that these $2k$-point correlators for Pauli operators completely determine the $k$-fold channel of an ensemble of unitary operators. Finally, we use a counting argument to obtain a lower bound on the quantum circuit complexity in terms of the frame potential. This provides a direct link between chaos, complexity, and randomness.
Quantum Chaos and Quantum Computers
Shepelyansky, D L
2001-01-01
The standard generic quantum computer model is studied analytically and numerically and the border for emergence of quantum chaos, induced by imperfections and residual inter-qubit couplings, is determined. This phenomenon appears in an isolated quantum computer without any external decoherence. The onset of quantum chaos leads to quantum computer hardware melting, strong quantum entropy growth and destruction of computer operability. The time scales for development of quantum chaos and ergodicity are determined. In spite the fact that this phenomenon is rather dangerous for quantum computing it is shown that the quantum chaos border for inter-qubit coupling is exponentially larger than the energy level spacing between quantum computer eigenstates and drops only linearly with the number of qubits n. As a result the ideal multi-qubit structure of the computer remains rather robust against imperfections. This opens a broad parameter region for a possible realization of quantum computer. The obtained results are...
Interpolity exchange of basalt tools facilitated via elite control in Hawaiian archaic states.
Kirch, Patrick V; Mills, Peter R; Lundblad, Steven P; Sinton, John; Kahn, Jennifer G
2012-01-24
Ethnohistoric accounts of late precontact Hawaiian archaic states emphasize the independence of chiefly controlled territories (ahupua'a) based on an agricultural, staple economy. However, elite control of unevenly distributed resources, such as high-quality volcanic rock for adze production, may have provided an alternative source of economic power. To test this hypothesis we used nondestructive energy-dispersive X-ray fluorescence (ED-XRF) analysis of 328 lithic artifacts from 36 archaeological features in the Kahikinui district, Maui Island, to geochemically characterize the source groups. This process was followed by a limited sampling using destructive wavelength-dispersive X-ray fluorescence (WD-XRF) analysis to more precisely characterize certain nonlocal source groups. Seventeen geochemical groups were defined, eight of which represent extra-Maui Island sources. Although the majority of stone tools were derived from Maui Island sources (71%), a significant quantity (27%) of tools derived from extraisland sources, including the large Mauna Kea quarry on Hawai'i Island as well as quarries on O'ahu, Moloka'i, and Lāna'i islands. Importantly, tools quarried from extralocal sources are found in the highest frequency in elite residential features and in ritual contexts. These results suggest a significant role for a wealth economy based on the control and distribution of nonagricultural goods and resources during the rise of the Hawaiian archaic states.
Bishop, Paul
2008-09-01
In 1930 Jung gave a lecture entitled 'Archaic Man' to the Lesezirkel in Hottingen. Following recent work on this text by two commentators, this article uses their interpretations as a springboard for a complementary reading, which emphasizes the fundamental significance of this paper as bridging the earlier and later stages in the development of analytical psychology, and examines closely the opposition between 'archaic'-'modern' in Jung's paper; indeed, in his work as a whole. In contrast to Lévy-Bruhl, Jung rejects the label of 'mysticism' as applied to the 'primitive' point of view, and his anti-mystical stance can be explained in terms of his dialectical conception of the relationship between Self and World. On this account, the subject and the object--the psyche and the external world--are more closely (inter)related than conventional (modern) epistemology and ontology generally believe. This conception of the relation between the subjective and the objective foreshadows his later, and controversial, concept of synchronicity, which is, Jung insists, a way of apprehending the world in terms of its meaning. Concluding with a survey of the status of the 'primordial' in some other texts by Jung, this article aims to foster further debate on one of Jung's most complex and fascinating texts.
Wu, Miaomiao; Xu, Shihui; Zhu, Wei; Mao, Xiaohua
2014-10-01
Subunit-subunit interactions of the classical and alternate chaperone-usher (CU) systems have been shown to proceed through a donor strand exchange (DSE) mechanism. However, it is not known whether DSE is required for intersubunit interactions in the archaic CU system. We have previously shown that the Myxococcus xanthus Mcu system, a member of the archaic CU family that functions in spore coat formation, is likely to use the principle of donor strand complementation to medicate chaperone-subunit interactions analogous to the classical CU pathway. Here we describe the results of studies on Mcu subunit-subunit interactions. We constructed a series of N-terminal-deleted, single amino acid-mutated and donor strand-complemented Mcu subunits, and characterized their abilities to participate in subunit-subunit interactions. It appears that certain residues in both the N and C termini of McuA, a subunit of the Mcu system, play a critical role in intersubunit interactions and these interactions may involve the general principle of DSE of the classical and alternate CU systems. In addition, the specificity of the M. xanthus CU system for Mcu subunits over other spore coat proteins is demonstrated.
Granular chaos and mixing: Whirled in a grain of sand
Energy Technology Data Exchange (ETDEWEB)
Shinbrot, Troy, E-mail: shinbrot@rutgers.edu [Department of Biomedical Engineering, Rutgers University, Piscataway, New Jersey 08854 (United States)
2015-09-15
In this paper, we overview examples of chaos in granular flows. We begin by reviewing several remarkable behaviors that have intrigued researchers over the past few decades, and we then focus on three areas in which chaos plays an intrinsic role in granular behavior. First, we discuss pattern formation in vibrated beds, which we show is a direct result of chaotic scattering combined with dynamical dissipation. Next, we consider stick-slip motion, which involves chaotic scattering on the micro-scale, and which results in complex and as yet unexplained peculiarities on the macro-scale. Finally, we examine granular mixing, which we show combines micro-scale chaotic scattering and macro-scale stick-slip motion into behaviors that are well described by dynamical systems tools, such as iterative mappings.
International Nuclear Information System (INIS)
ZnO typifies a class of materials that can be doped via native defects in only one way: either n type or p type. We explain this asymmetry in ZnO via a study of its intrinsic defect physics, including ZnO, Zni, VO, Oi, and VZn and n-type impurity dopants, Al and F. We find that ZnO is n type at Zn-rich conditions. This is because (i) the Zn interstitial, Zni, is a shallow donor, supplying electrons; (ii) its formation enthalpy is low for both Zn-rich and O-rich conditions, so this defect is abundant; and (iii) the native defects that could compensate the n-type doping effect of Zni (interstitial O, Oi, and Zn vacancy, VZn), have high formation enthalpies for Zn-rich conditions, so these ''electron killers'' are not abundant. We find that ZnO cannot be doped p type via native defects (Oi,VZn) despite the fact that they are shallow (i.e., supplying holes at room temperature). This is because at both Zn-rich and O-rich conditions, the defects that could compensate p-type doping (VO,Zni,ZnO) have low formation enthalpies so these ''hole killers'' form readily. Furthermore, we identify electron-hole radiative recombination at the VO center as the source of the green luminescence. In contrast, a large structural relaxation of the same center upon double hole capture leads to slow electron-hole recombination (either radiative or nonradiative) responsible for the slow decay of photoconductivity
Decoherence, determinism and chaos
International Nuclear Information System (INIS)
The author claims by now to have made his case that modern work on fractals and chaos theory has already removed the presumption that classical physics is 'deterministic'. Further, he claims that in so far as classical relativistic field theory (i.e. electromagnetism and gravitation) are scale invariant, they are self-consistent only if the idea of 'test-particle' is introduced from outside the theory. Einstein spent the last years of his life trying to use singularities in the metric as 'particles' or to get them out of the non-linearities in a grand unified theory -- in vain. So classical physics in this sense cannot be the fundamental theory. However, the author claims to have shown that if he introduces a 'scale invariance bounded from below' by measurement accuracy, then Tanimura's generalization of the Feynman proof as reconstructed by Dyson allows him to make a consistent classical theory for decoherent sources sinks. Restoring coherence to classical physics via relativistic action-at-a distance is left as a task for the future. Relativistic quantum mechanics, properly reconstructed from a finite and discrete basis, emerges in much better shape. The concept of 'particles has to be replaced by NO-YES particulate events, and particle-antiparticle pair creation and annihilation properly formulated
2012 Symposium on Chaos, Complexity and Leadership
Erçetin, Şefika
2014-01-01
These proceedings from the 2012 symposium on "Chaos, complexity and leadership" reflect current research results from all branches of Chaos, Complex Systems and their applications in Management. Included are the diverse results in the fields of applied nonlinear methods, modeling of data and simulations, as well as theoretical achievements of Chaos and Complex Systems. Also highlighted are Leadership and Management applications of Chaos and Complexity Theory.
From archaic narcissism to empathy for the self: the evolution of new capacities in psychoanalysis.
Gehrie, Mark J
2011-04-01
The concept of the selfobject was central to Heinz Kohut's psychology of the self. With an eye to studying the development of narcissism and its implications for the growth of new psychic structure, this concept is reviewed and reassessed. Post-Kohutian complexities regarding its definition and use extend our consideration of the development of narcissism beyond archaic configurations toward further evolution of the self and the nature of mature narcissism. The hypothesis is offered that developing narcissism and the growth of self-regulation impact the acquisition of new structure and new capacities through the emergence of newly potentiated aspects of the self. The implications of these emergent qualities of the self are examined in the context of our understanding of self-esteem regulation, the state of the self, and the goals of psychoanalysis. A clinical example illustrates how technique and process in an analysis may be organized around the development of such new capacities.
Chaos theory for the biomedical engineer.
Eberhart, R C
1989-01-01
A brief introduction to chaos theory is provided. Definitions of chaos and attributes of chaos and fractals are discussed. Several general examples are examined, and fractals are introduced with a brief look at the Mandelbrot and Julia sets. Biomedical examples of chaotic behaviour and fractals are presented.
Chromosomal Rearrangements as Barriers to Genetic Homogenization between Archaic and Modern Humans.
Rogers, Rebekah L
2015-12-01
Chromosomal rearrangements, which shuffle DNA throughout the genome, are an important source of divergence across taxa. Using a paired-end read approach with Illumina sequence data for archaic humans, I identify changes in genome structure that occurred recently in human evolution. Hundreds of rearrangements indicate genomic trafficking between the sex chromosomes and autosomes, raising the possibility of sex-specific changes. Additionally, genes adjacent to genome structure changes in Neanderthals are associated with testis-specific expression, consistent with evolutionary theory that new genes commonly form with expression in the testes. I identify one case of new-gene creation through transposition from the Y chromosome to chromosome 10 that combines the 5'-end of the testis-specific gene Fank1 with previously untranscribed sequence. This new transcript experienced copy number expansion in archaic genomes, indicating rapid genomic change. Among rearrangements identified in Neanderthals, 13% are transposition of selfish genetic elements, whereas 32% appear to be ectopic exchange between repeats. In Denisovan, the pattern is similar but numbers are significantly higher with 18% of rearrangements reflecting transposition and 40% ectopic exchange between distantly related repeats. There is an excess of divergent rearrangements relative to polymorphism in Denisovan, which might result from nonuniform rates of mutation, possibly reflecting a burst of transposable element activity in the lineage that led to Denisovan. Finally, loci containing genome structure changes show diminished rates of introgression from Neanderthals into modern humans, consistent with the hypothesis that rearrangements serve as barriers to gene flow during hybridization. Together, these results suggest that this previously unidentified source of genomic variation has important biological consequences in human evolution. PMID:26399483
CT-based description and phyletic evaluation of the archaic human calvarium from Ceprano, Italy.
Bruner, Emiliano; Manzi, Giorgio
2005-07-01
The discovery in 1994, of a fossilized human calvarium near Ceprano, Italy, dated about 800-900 thousand years before present, opened a new page for the study of human evolution in Europe. It extended the continental fossil record over the boundary between Early and Middle Pleistocene for the first time and revealed the cranial morphology of humans that where probably ancestral to both Neanderthals and modern Homo sapiens. A tomographic analysis of the Italian specimen is reported here in order to describe size and shape, vascular traces, and other features of the endocranium, as well as some relevant ectocranial traits (particularly of the frontal region). Our results show that the Ceprano calvarium displays plesiomorphies shared by early Homo taxa, involving a general archaic phenotype. At the same time, the presence of some derived features suggests a phylogenetic relationship with the populations referred to the subsequent polymorphic species H. heidelbergensis. The morphology of the supraorbital structures is different from the double-arched browridge of the African H. ergaster, while its superior shape shows similarities with African Middle Pleistocene specimens (Bodo, Kabwe). In contrast, the relationship between supraorbital torus and frontal squama points to an archaic pattern of the relationship between face and vault, associated to moderately narrow frontal lobes and limited development of the upper parietal areas. Despite a nonderived endocranial shape, the increase of cranial capacity (related to a general endocranial widening) and the probable absence of a clear occipital projection also suggest an evolutionary independence from the Asian H. erectus lineage. This analysis therefore supports the conclusion that the Ceprano calvarium represents the best available candidate for the ancestral phenotype of the cranial variation observed among Middle Pleistocene fossil samples in Africa and Europe. Nevertheless, a proper taxonomic interpretation of this
Turiaci, Gustavo
2016-01-01
We make three observations that help clarify the relation between CFT and quantum chaos. We show that any 1+1-D system in which conformal symmetry is non-linearly realized exhibits two main characteristics of chaos: maximal Lyapunov behavior and a spectrum of Ruelle resonances. We use this insight to identify a lattice model for quantum chaos, built from parafermionic spin variables with an equation of motion given by a Y-system. Finally we point to a relation between the spectrum of Ruelle resonances of a CFT and the analytic properties of OPE coefficients between light and heavy operators. In our model, this spectrum agrees with the quasi-normal modes of the BTZ black hole.
Quantum chaos in multiwell potentials
International Nuclear Information System (INIS)
Till the present time signatures of quantum chaos were studied mostly for the billiard-type systems, for dumped one-dimensional systems or for two-dimensional systems with potential energy surface of simple geometry. Almost nothing is known about the quantum chaos for generic Hamiltonian systems, including multiwell potentials, though those are the models describing the dynamics of transition between different states, for example, nuclear isomeric transitions and decay of superdeformed states of nuclei. An important feature of classical dynamics in generic multiwell potentials is the so-called mixed state, namely: regular and chaotic regimes coexist at the same energy, being localized in different local minima of the potential. The aim of our work is to show that studies of quantum chaos in the mixed state are promising and in many cases optimal. (author)
Chaos: A historical perspective
Lighthill, James
In this introductory lecture I'd like to offer a broad historical perspective regarding the relatively recent general recognition: (a) that mechanical systems satisfying Newton's laws may be subject to the essentially unpredictable type of behavior which the word CHAOS describes—in other words, the recognition (b) that quantum effects are not required; (c) so that, notwithstanding Heisenberg, uncertainty is there on the basis of the good old classical mechanics based on Newton's Laws. But first of all I'll remind you that there are two kinds of laws in science, which we may exemplify by Kepler's Laws and Newton's Laws. Kepler in 1609 completed some very detailed observations of the motions of Mars; together with a full geometrical description of them, in the Copernican sun-centered flame of reference, as motions in a constant orbit in the shape of an ellipse with the Sun as focus. A decade later Kepler had published the Epitome Astronomiae Copernicanae (a rather more substantial work than the Dialogo which later got Galileo into some difficulties), and had there described in detail his most famous discovery: Kepler's three empirical laws concerning planetary orbits. These laws, of the elliptical shapes of orbits, of the radius covering equal areas in equal times, and of the proportionality of the square of the orbital period to the cube of the major axis, were shown from the observations to be closely satisfied by the Earth and by the five then known planets; and furthermore, by the four satellites of Jupiter which Galileo had recently discovered.
Deterministic polarization chaos from a laser diode
Virte, Martin; Thienpont, Hugo; Sciamanna, Marc
2014-01-01
Fifty years after the invention of the laser diode and fourty years after the report of the butterfly effect - i.e. the unpredictability of deterministic chaos, it is said that a laser diode behaves like a damped nonlinear oscillator. Hence no chaos can be generated unless with additional forcing or parameter modulation. Here we report the first counter-example of a free-running laser diode generating chaos. The underlying physics is a nonlinear coupling between two elliptically polarized modes in a vertical-cavity surface-emitting laser. We identify chaos in experimental time-series and show theoretically the bifurcations leading to single- and double-scroll attractors with characteristics similar to Lorenz chaos. The reported polarization chaos resembles at first sight a noise-driven mode hopping but shows opposite statistical properties. Our findings open up new research areas that combine the high speed performances of microcavity lasers with controllable and integrated sources of optical chaos.
Distributed chaos in turbulent wakes
Bershadskii, A
2016-01-01
Soft and hard spontaneous breaking of space translational symmetry (homogeneity) have been studied in turbulent wakes by means of distributed chaos. In the case of the soft translational symmetry breaking the vorticity correlation integral $\\int_{V} \\langle {\\boldsymbol \\omega} ({\\bf x},t) \\cdot {\\boldsymbol \\omega} ({\\bf x} + {\\bf r},t) \\rangle_{V} d{\\bf r}$ dominates the distributed chaos and the chaotic spectra $\\exp-(k/k_{\\beta})^{\\beta }$ have $\\beta =1/2$. In the case of the hard translational symmetry breaking, control on the distributed chaos is switched from one type of fundamental symmetry to another (in this case to Lagrangian relabeling symmetry). Due to the Noether's theorem the relabeling symmetry results in the inviscid helicity conservation and helicity correlation integral $I=\\int \\langle h({\\bf x},t)~h({\\bf x}+{\\bf r}, t)\\rangle d{\\bf r}$ (Levich-Tsinober invariant) dominates the distributed chaos with $\\beta =1/3$. Good agreement with the experimatal data has been established for turbulent ...
Wang, Frank Y
2009-01-01
The general public has been made aware of the research field of "chaos" by the book of that title by James Gleick. This paper will focus on the achievements of Sonya Kovalevskaya, Mary Cartwright, and Mary Tsingou, whose pioneer works were not mentioned in Gleick's book.
MHD turbulence and distributed chaos
Bershadskii, A
2016-01-01
It is shown, using results of recent direct numerical simulations, that spectral properties of distributed chaos in MHD turbulence with zero mean magnetic field are similar to those of hydrodynamic turbulence. An exception is MHD spontaneous breaking of space translational symmetry, when the stretched exponential spectrum $\\exp(-k/k_{\\beta})^{\\beta}$ has $\\beta=4/7$.
Chaos Behaviour of Molecular Orbit
Institute of Scientific and Technical Information of China (English)
LIU Shu-Tang; SUN Fu-Yan; SHEN Shu-Lan
2007-01-01
Based on H(u)ckel's molecular orbit theory,the chaos and;bifurcation behaviour of a molecular orbit modelled by a nonlinear dynamic system is studied.The relationship between molecular orbit and its energy level in the nonlinear dynamic system is obtained.
Directory of Open Access Journals (Sweden)
Antonia Vieira dos Santos
2014-07-01
Full Text Available The use of hyphen within compounds was not built up before the nineteenth century. Thus, compounds spelled with hyphen in archaic Portuguese texts are a result of editing criteria adopted by editors. From this type of intervention, the relationship between hyphen use – result of a spelling convention – and the definition of compound adopted by the editor are discussed. Its absence is significant to the history of the language.
Directory of Open Access Journals (Sweden)
Kasianenko O.G.
2009-10-01
Full Text Available The author has realized the historical analysis of one of the information sources about Ancient Olympic games, namely lists of winners. Had presented the description of geographical information, characterizing the sportsmen's place of origin, and also social origin of afore-named, allows to conduct parallels in consideration of the studied information with political and cultural changes in Greek civilization in archaic and classic periods which had a direct influence on the Olympic Games.
Hsieh, PingHsun; Woerner, August E; Wall, Jeffrey D; Lachance, Joseph; Tishkoff, Sarah A; Gutenkunst, Ryan N; Hammer, Michael F
2016-03-01
Comparisons of whole-genome sequences from ancient and contemporary samples have pointed to several instances of archaic admixture through interbreeding between the ancestors of modern non-Africans and now extinct hominids such as Neanderthals and Denisovans. One implication of these findings is that some adaptive features in contemporary humans may have entered the population via gene flow with archaic forms in Eurasia. Within Africa, fossil evidence suggests that anatomically modern humans (AMH) and various archaic forms coexisted for much of the last 200,000 yr; however, the absence of ancient DNA in Africa has limited our ability to make a direct comparison between archaic and modern human genomes. Here, we use statistical inference based on high coverage whole-genome data (greater than 60×) from contemporary African Pygmy hunter-gatherers as an alternative means to study the evolutionary history of the genus Homo. Using whole-genome simulations that consider demographic histories that include both isolation and gene flow with neighboring farming populations, our inference method rejects the hypothesis that the ancestors of AMH were genetically isolated in Africa, thus providing the first whole genome-level evidence of African archaic admixture. Our inferences also suggest a complex human evolutionary history in Africa, which involves at least a single admixture event from an unknown archaic population into the ancestors of AMH, likely within the last 30,000 yr.
Rice Varieties in Archaic East Asia: Reduction of Its Diversity from Past to Present Times.
Kumagai, Masahiko; Kanehara, Masaaki; Shoda, Shin'ya; Fujita, Saburo; Onuki, Shizuo; Ueda, Shintaroh; Wang, Li
2016-10-01
The Asian cultivated rice, Oryza sativa, is one of the most important crops feeding more than a third of global population. In spite of the studies for several decades, the origin and domestication history of rice varietal groups, japonica and indica, have not been fully unveiled. Genetic information of ancient rice remains is essential for direct and exclusive insight into the domestication history of rice. We performed ancient DNA analysis of 950- to 2,800-year-old rice remains excavated from Japan and Korea. We found the presence of both japonica- and indica-type varieties in the Yayoi period and the middle ages of Japan and the middle part of Korea Peninsula 2,000 years ago. It is popularly considered that japonica has been exclusively cultivated in northern part of East Asia including Japan and Korea. Our result disclosed unexpectedly wide diversity of rice varieties in archaic East Asia. The present results from ancient rice DNA reveal an exclusive insight for the domestication history of rice which is not provided as far as contemporary rice. PMID:27461246
Directory of Open Access Journals (Sweden)
Yang Liu
Full Text Available Mitochondrial genomes have maintained some bacterial features despite their residence within eukaryotic cells for approximately two billion years. One of these features is the frequent presence of polycistronic operons. In land plants, however, it has been shown that all sequenced vascular plant chondromes lack large polycistronic operons while bryophyte chondromes have many of them. In this study, we provide the completely sequenced mitochondrial genome of a lycophyte, from Huperzia squarrosa, which is a member of the sister group to all other vascular plants. The genome, at a size of 413,530 base pairs, contains 66 genes and 32 group II introns. In addition, it has 69 pseudogene fragments for 24 of the 40 protein- and rRNA-coding genes. It represents the most archaic form of mitochondrial genomes of all vascular plants. In particular, it has one large conserved gene cluster containing up to 10 ribosomal protein genes, which likely represents a polycistronic operon but has been disrupted and greatly reduced in the chondromes of other vascular plants. It also has the least rearranged gene order in comparison to the chondromes of other vascular plants. The genome is ancestral in vascular plants in several other aspects: the gene content resembling those of charophytes and most bryophytes, all introns being cis-spliced, a low level of RNA editing, and lack of foreign DNA of chloroplast or nuclear origin.
Investigation of Chinese archaic jade by PIXE and {mu}Raman spectrometry
Energy Technology Data Exchange (ETDEWEB)
Chen, T.H. [UMR 171 du CNRS, Centre de Recherche et de Restauration des Musees de France, Palais du Louvre, Porte des Lions, 14 Quai Francois Mitterrand, 75001, Paris (France); Ecole Doctorale MMRMM, Universite de Versailles - St Quentin en Yvelines, 45 Avenue des Etats Unis, 78035, Versailles Cedex (France); Calligaro, T.; Pages-Camagna, S.; Menu, M. [UMR 171 du CNRS, Centre de Recherche et de Restauration des Musees de France, Palais du Louvre, Porte des Lions, 14 Quai Francois Mitterrand, 75001, Paris (France)
2004-07-01
External-beam particle-induced X-ray emission (PIXE) and {mu}Raman spectrometry were used for elemental and structural studies of Chinese archaic nephrite jades of the Guimet Asian Museum in Paris in a non-destructive way. Nephrite is a variety of tremolite-actinolite of the amphibole group, with variable iron and magnesium contents. In the present work, in addition to identification of materials, the cation distribution in nephrite was investigated. Cation order-disorder is related to thermodynamic properties of minerals, and hence associated with geological conditions of the mineral formation. Besides, it plays an important role in the mechanism of coloration. So far, little work has been done on the cation distribution in nephrite. We thus initiated this research expecting to answer open questions concerning art and archaeological issues such as jade provenance and colour. The OH stretching vibration band of nephrite, depending on the electronegativity of the bonded cations, presents a fine structure. The study of this fine structure, together with the total cation content obtained by PIXE, allows estimation of the cation distribution in nephrite. In this study, six jade artefacts, dated from the Neolithic period to the Han dynasty (about 3000 BC to 220 AD), with diverse colours including white, yellow-green, green, dark green and black, were analysed. The data obtained permits establishing a geological database for determination of nephrite provenance and explaining the correlation between colour and cation distribution. (orig.)
Investigation of Chinese archaic jade by PIXE and μRaman spectrometry
Chen, T.-H.; Calligaro, T.; Pagès-Camagna, S.; Menu, M.
External-beam particle-induced X-ray emission (PIXE) and μRaman spectrometry were used for elemental and structural studies of Chinese archaic nephrite jades of the Guimet Asian Museum in Paris in a non-destructive way. Nephrite is a variety of tremolite-actinolite of the amphibole group, with variable iron and magnesium contents. In the present work, in addition to identification of materials, the cation distribution in nephrite was investigated. Cation order-disorder is related to thermodynamic properties of minerals, and hence associated with geological conditions of the mineral formation. Besides, it plays an important role in the mechanism of coloration. So far, little work has been done on the cation distribution in nephrite. We thus initiated this research expecting to answer open questions concerning art and archaeological issues such as jade provenance and colour. The OH stretching vibration band of nephrite, depending on the electronegativity of the bonded cations, presents a fine structure. The study of this fine structure, together with the total cation content obtained by PIXE, allows estimation of the cation distribution in nephrite. In this study, six jade artefacts, dated from the Neolithic period to the Han dynasty (about 3000 BC to 220 AD), with diverse colours including white, yellow-green, green, dark green and black, were analysed. The data obtained permits establishing a geological database for determination of nephrite provenance and explaining the correlation between colour and cation distribution.
Advances in chaos theory and intelligent control
Vaidyanathan, Sundarapandian
2016-01-01
The book reports on the latest advances in and applications of chaos theory and intelligent control. Written by eminent scientists and active researchers and using a clear, matter-of-fact style, it covers advanced theories, methods, and applications in a variety of research areas, and explains key concepts in modeling, analysis, and control of chaotic and hyperchaotic systems. Topics include fractional chaotic systems, chaos control, chaos synchronization, memristors, jerk circuits, chaotic systems with hidden attractors, mechanical and biological chaos, and circuit realization of chaotic systems. The book further covers fuzzy logic controllers, evolutionary algorithms, swarm intelligence, and petri nets among other topics. Not only does it provide the readers with chaos fundamentals and intelligent control-based algorithms; it also discusses key applications of chaos as well as multidisciplinary solutions developed via intelligent control. The book is a timely and comprehensive reference guide for graduate s...
Controlling neuronal noise using chaos control
Christini, D J; Christini, David J; Collins, James J
1995-01-01
Chaos control techniques have been applied to a wide variety of experimental systems, including magneto-elastic ribbons, lasers, chemical reactions, arrhythmic cardiac tissue, and spontaneously bursting neuronal networks. An underlying assumption in all of these studies is that the system being controlled is chaotic. However, the identification of chaos in experimental systems, particularly physiological systems, is a difficult and often misleading task. Here we demonstrate that the chaos criteria used in a recent study can falsely classify a noise-driven, non-chaotic neuronal model as being chaotic. We apply chaos control, periodic pacing, and anticontrol to the non-chaotic model and obtain results which are similar to those reported for apparently chaotic, {\\em in vitro} neuronal networks. We also obtain similar results when we apply chaos control to a simple stochastic system. These novel findings challenge the claim that the aforementioned neuronal networks were chaotic and suggest that chaos control tech...
Recent Developments on Chaos in Mechanical Systems
Mohammad Sajid
2013-01-01
Recent advancements in complexity of mechanical systems have led to the application of chaos theory. In this paper, some recent developments on chaos in mechanical systems are explored. The aim is to bring together researchers from various interests of mechanical systems, exposing them to chaos theory. This exposure gives researchers from the discipline of mechanical systems to find opportunity of cross disciplinary research, which may ultimately lead to novel solutions and understanding of m...
Fitzpatrick, A Liam
2016-01-01
We use results on Virasoro conformal blocks to study chaotic dynamics in CFT$_2$ at large central charge c. The Lyapunov exponent $\\lambda_L$, which is a diagnostic for the early onset of chaos, receives $1/c$ corrections that may be interpreted as $\\lambda_L = \\frac{2 \\pi}{\\beta} \\left( 1 + \\frac{12}{c} \\right)$. However, out of time order correlators receive other equally important $1/c$ suppressed contributions that do not have such a simple interpretation. We revisit the proof of a bound on $\\lambda_L$ that emerges at large $c$, focusing on CFT$_2$ and explaining why our results do not conflict with the analysis leading to the bound. We also comment on relationships between chaos, scattering, causality, and bulk locality.
Spatiotemporal chaos from bursting dynamics
Energy Technology Data Exchange (ETDEWEB)
Berenstein, Igal; De Decker, Yannick [Nonlinear Physical Chemistry Unit and Interdisciplinary Center for Nonlinear Phenomena and Complex Systems (CENOLI), Faculté des Sciences, Université libre de Bruxelles (ULB), Campus Plaine, C.P. 231, B-1050 Brussels (Belgium)
2015-08-14
In this paper, we study the emergence of spatiotemporal chaos from mixed-mode oscillations, by using an extended Oregonator model. We show that bursting dynamics consisting of fast/slow mixed mode oscillations along a single attractor can lead to spatiotemporal chaotic dynamics, although the spatially homogeneous solution is itself non-chaotic. This behavior is observed far from the Hopf bifurcation and takes the form of a spatiotemporal intermittency where the system locally alternates between the fast and the slow phases of the mixed mode oscillations. We expect this form of spatiotemporal chaos to be generic for models in which one or several slow variables are coupled to activator-inhibitor type of oscillators.
Chaos in the library environment
Κατσιρίκου, Ανθή
2001-01-01
Describes the impact of chaos theory in social systems and the phenomena that result from it, drawing attention to related phenomena in the state of the library today. Then considers the factors that lead library systems to exhibit chaotic behaviour. These factors are the plethora of technological tools and the variety of software and interfaces, the dependence of resource providers and the increasing supply and diversity of information resources. The changes dictated by these factors influen...
Chaos and multiple photon absorption
International Nuclear Information System (INIS)
An anharmonic vibrational mode of a molecule, driven by an intense infrared laser and coupled to a quasi-continuum of background modes, is found to undergo chaotic oscillations. This chaos leads to predominantly fluence-dependent rather than intensity-dependent multiple-photon absorption, as is found experimentally. The loss of coherence is associated with the decay of temporal correlation of background-mode oscillations
Random Behaviour in Quantum Chaos
Garbaczewski, P
2001-01-01
We demonstrate that a family of radial Ornstein-Uhlenbeck stochastic processes displays an ergodic behaviour appropriate for known quantum chaos universality classes of nearest neighbour spacing distributions. A common feature of those parametric processes is an asymptotic balance between the radial (Bessel-type) repulsion and the harmonic attraction, as manifested in the general form of forward drifts $b(x) = {{N-1}\\over {2x}} - x$, ($N = 2,3,5$ correspond respectively to the familiar GOE, GUE and GSE cases).
Analysis of FBC deterministic chaos
Energy Technology Data Exchange (ETDEWEB)
Daw, C.S.
1996-06-01
It has recently been discovered that the performance of a number of fossil energy conversion devices such as fluidized beds, pulsed combustors, steady combustors, and internal combustion engines are affected by deterministic chaos. It is now recognized that understanding and controlling the chaotic elements of these devices can lead to significantly improved energy efficiency and reduced emissions. Application of these techniques to key fossil energy processes are expected to provide important competitive advantages for U.S. industry.
The chaos cookbook a practical programming guide
Pritchard, Joe
2014-01-01
The Chaos Cookbook: A Practical Programming Guide discusses the use of chaos in computer programming. The book is comprised of 11 chapters that tackle various topics relevant to chaos and programming. Chapter 1 reviews the concept of chaos, and Chapter 2 discusses the iterative functions. Chapters 3 and 4 cover differential and Lorenz equations. Chapter 5 talks about strange attractors, while Chapter 6 deals with the fractal link. The book also discusses the Mandelbrot set, and then covers the Julia sets. The other fractal systems and the cellular automata are also explained. The last chapter
Master stability analysis in transient spatiotemporal chaos.
Wackerbauer, Renate
2007-11-01
The asymptotic stability of spatiotemporal chaos is difficult to determine, since transient spatiotemporal chaos may be extremely long lived. A master stability analysis reveals that the asymptotic state of transient spatiotemporal chaos in the Gray-Scott system and in the Bär-Eiswirth system is characterized by negative transverse Lyapunov exponents on the attractor of the invariant synchronization manifold. The average lifetime of transient spatiotemporal chaos depends on the number of transverse directions that are unstable along a typical excitation cycle. PMID:18233739
Hamiltonian chaos and fractional dynamics
Zaslavsky, George M
2008-01-01
The dynamics of realistic Hamiltonian systems has unusual microscopic features that are direct consequences of its fractional space-time structure and its phase space topology. The book deals with the fractality of the chaotic dynamics and kinetics, and also includes material on non-ergodic and non-well-mixing Hamiltonian dynamics. The book does not follow the traditional scheme of most of today's literature on chaos. The intention of the author has been to put together some of the most complex and yet open problems on the general theory of chaotic systems. The importance of the discussed issues and an understanding of their origin should inspire students and researchers to touch upon some of the deepest aspects of nonlinear dynamics. The book considers the basic principles of the Hamiltonian theory of chaos and some applications including for example, the cooling of particles and signals, control and erasing of chaos, polynomial complexity, Maxwell's Demon, and others. It presents a new and realistic image ...
Kasimov, Aslan R.
2013-03-08
We propose the following model equation, ut+1/2(u2−uus)x=f(x,us) that predicts chaotic shock waves, similar to those in detonations in chemically reacting mixtures. The equation is given on the half line, x<0, and the shock is located at x=0 for any t≥0. Here, us(t) is the shock state and the source term f is taken to mimic the chemical energy release in detonations. This equation retains the essential physics needed to reproduce many properties of detonations in gaseous reactive mixtures: steady traveling wave solutions, instability of such solutions, and the onset of chaos. Our model is the first (to our knowledge) to describe chaos in shock waves by a scalar first-order partial differential equation. The chaos arises in the equation thanks to an interplay between the nonlinearity of the inviscid Burgers equation and a novel forcing term that is nonlocal in nature and has deep physical roots in reactive Euler equations.
Landmark-based shape analysis of the archaic Homo calvarium from Ceprano (Italy).
Bruner, Emiliano; Manzi, Giorgio
2007-03-01
The Ceprano calvarium represents one of the most important sources of information about both the dynamics of the earliest hominid dispersal toward Europe and the evolution of the genus Homo in the early-to-middle Pleistocene. In this paper, the midsagittal vault profile and the 3D frontal bone morphology of Ceprano are investigated comparatively, using landmark coordinates and Procrustes superimposition. In fact, despite the fact that the skull appears partially distorted by diagenetic pressures (thus precluding a comprehensive landmark-based analysis), some aspects of the overall morphology are suitable for consideration in terms of geometric morphometrics. The midsagittal profile shows an archaic shape, comparable with the H. ergaster/erectus range of variation because of the fronto-parietal flattening, the development of the supraorbital and nuchal structures, and the occurrence of a slightly larger occipital bone. By contrast, the frontal bone displays a derived 3D shape that, mostly because of the widening of the frontal squama, appears comparable with the Afro-European variation of the Middle Pleistocene (i.e., H. heidelbergensis/rhodesiensis). Taking into account the unique morphological pattern displayed by Ceprano, its role as a link between early Homo and the Middle Pleistocene populations of Europe and Africa is not falsified. Thus, when aspects of the Ceprano's morphology are described within the analytical framework provided by geometric morphometrics, the relationships between Ceprano and the subsequent Afro-European fossil record are emphasized, suggesting the occurrence of an ancestral stock of H. heidelbergensis/rhodesiensis that is properly represented by the Italian specimen. PMID:17177181
Directory of Open Access Journals (Sweden)
Mónica Díaz
2011-01-01
Full Text Available Introduction: Ancient DNA (aDNAstudies can support hypotheses regarding ancient populations; molecular studies can analyze the local population’s genetic composition, minimizing biases introduced by later migrations, demographic expansions, mutations, and bottleneck effects. These analyses must be performed with special care because of the low DNA concentrations and contamination risk; therefore, it is necessary to establish protocols to guarantee the reproducibility and veracity of results. Objective: The present study aims to establish a protocol to obtain ancient DNA from 16 pre-Columbian bone samples found in an excavation performed in the area «Candelaria La Nueva» in Bogota, Colombia, dated in the period «Muisca Tardio». Methods: Four founder mitochondrial DNA Amerindian haplotypes were analyzed by high resolution restriction enzyme analyses, obtaining fragments between 121 and 186 base pairs (bp. Different analyses were performed following a strict control of authenticity criteria regarding laboratory conditions, including: positive and negative controls, reproducibility of results, and verification of particular characteristics present in ancient DNA. Results: Results obtained from the bone samples showed the exclusive presence of haplogroup A in the population studied. This data support the statement of the archaeologists of a single biological population in space and time. The distribution of this haplogroup in a 100% frequency supports the hypothesis of Chibcha genetic affiliation. Conclusion: The present study is a contribution to the study of genetic diversity in archaic American populations, allowing the integration of geographic and historic data with genetic characterization techniques associated with linguistic, ethnographic, and glottochronology patterns. Following the protocol proposed in the present study allows fulfilling authenticity criteria for ancient samples with the available techniques.
Weak chaos in the asymmetric heavy top
Barrientos, M; Ranada, A F
1995-01-01
We consider the dynamics of the slightly asymmetric heavy top, a non-integrable system obtained from the Lagrange top by breaking the symmetry of its inertia tensor. It shows signs of weak chaos, which we study numerically. We argue that it is a good example for introducing students to non-integrability and chaos. (author)
Chaos and fractals. Applications to nuclear engineering
International Nuclear Information System (INIS)
This work presents a description of the research lines carried out by the authors on chaos and fractal theories, oriented to the nuclear field. The possibilities that appear in the nuclear security branch where the information deriving from chaos and fractal techniques may help to the development of better criteria and more reliable designs, are of special importance. (Author)
Chaos desynchronization in strongly coupled systems
Energy Technology Data Exchange (ETDEWEB)
Wu Ye [Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); School of Science, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Liu Weiqing [Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China); Graduate School of the Chinese Academy of Sciences, Beijing 100049 (China); School of Science, Beijing University of Posts and Telecommunications, Beijing 100876 (China); School of Science, Jiangxi University of Science and Technology, Ganzhou 341000 (China); Xiao, Jinghua [School of Science, Beijing University of Posts and Telecommunications, Beijing 100876 (China); Zhan Meng [Wuhan Institute of Physics and Mathematics, Chinese Academy of Sciences, Wuhan 430071 (China)], E-mail: zhanmeng@wipm.ac.cn
2007-10-01
The dynamics of chaos desynchronization in strongly coupled oscillator systems is studied. We find a new bifurcation from synchronous chaotic state, chaotic short wave bifurcation, i.e. a chaotic desynchronization attractor is new born in the systems due to chaos desynchronization. In comparison with the usual periodic short wave bifurcation, very rich but distinct phenomena are observed.
Radio lighting based on dynamic chaos generators
Dmitriev, Alexander; Gerasimov, Mark; Itskov, Vadim
2016-01-01
A problem of lighting objects and surfaces with artificial sources of noncoherent microwave radiation with the aim to observe them using radiometric equipment is considered. Transmitters based on dynamic chaos generators are used as sources of noncoherent wideband microwave radiation. An experimental sample of such a device, i.e., a radio lighting lamp based on a chaos microgenerator and its performance are presented.
"Chaos" Theory: Implications for Educational Research.
Lindsay, Jean S.
"Chaos" theory is a revolutionary new paradigm developed by scientists to study the behavior of natural systems. "Chaos" refers to the tendency of dynamic non-linear systems toward irregular, sometimes unpredictable, yet deterministic behavior. Major tenets of the theory are presented. The precedent for use of models developed in the natural…
The CHAOS-4 geomagnetic field model
DEFF Research Database (Denmark)
Olsen, Nils; Lühr, H.; Finlay, Chris;
2014-01-01
We present CHAOS-4, a new version in the CHAOS model series, which aims to describe the Earth's magnetic field with high spatial and temporal resolution. Terms up to spherical degree of at least n = 85 for the lithospheric field, and up to n = 16 for the time-varying core field are robustly deter...
Path and semimartingale properties of chaos processes
DEFF Research Database (Denmark)
Basse-O'Connor, Andreas; Graversen, Svend-Erik
2010-01-01
The present paper characterizes various properties of chaos processes which in particular include processes where all time variables admit a Wiener chaos expansion of a fixed finite order. The main focus is on the semimartingale property, p-variation and continuity. The general results obtained a...
Chaos the science of predictable random motion
Kautz, Richard
2011-01-01
Based on only elementary mathematics, this engaging account of chaos theory bridges the gap between introductions for the layman and college-level texts. It develops the science of dynamics in terms of small time steps, describes the phenomenon of chaos through simple examples, and concludes with a close look at a homoclinic tangle, the mathematical monster at the heart of chaos. The presentation is enhanced by many figures, animations of chaotic motion (available on a companion CD), and biographical sketches of the pioneers of dynamics and chaos theory. To ensure accessibility to motivated high school students, care has been taken to explain advanced mathematical concepts simply, including exponentials and logarithms, probability, correlation, frequency analysis, fractals, and transfinite numbers. These tools help to resolve the intriguing paradox of motion that is predictable and yet random, while the final chapter explores the various ways chaos theory has been put to practical use.
Semiconductor Lasers Stability, Instability and Chaos
Ohtsubo, Junji
2013-01-01
This third edition of “Semiconductor Lasers, Stability, Instability and Chaos” was significantly extended. In the previous edition, the dynamics and characteristics of chaos in semiconductor lasers after the introduction of the fundamental theory of laser chaos and chaotic dynamics induced by self-optical feedback and optical injection was discussed. Semiconductor lasers with new device structures, such as vertical-cavity surface-emitting lasers and broad-area semiconductor lasers, are interesting devices from the viewpoint of chaotic dynamics since they essentially involve chaotic dynamics even in their free-running oscillations. These topics are also treated with respect to the new developments in the current edition. Also the control of such instabilities and chaos control are critical issues for applications. Another interesting and important issue of semiconductor laser chaos in this third edition is chaos synchronization between two lasers and the application to optical secure communication. One o...
PHASE CHAOS IN THE DISCRETE KURAMOTO MODEL
DEFF Research Database (Denmark)
Maistrenko, V.; Vasylenko, A.; Maistrenko, Y.;
2010-01-01
The paper describes the appearance of a novel, high-dimensional chaotic regime, called phase chaos, in a time-discrete Kuramoto model of globally coupled phase oscillators. This type of chaos is observed at small and intermediate values of the coupling strength. It arises from the nonlinear...... interaction among the oscillators, while the individual oscillators behave periodically when left uncoupled. For the four-dimensional time-discrete Kuramoto model, we outline the region of phase chaos in the parameter plane and determine the regions where phase chaos coexists with different periodic...... attractors. We also study the subcritical frequency-splitting bifurcation at the onset of desynchronization and demonstrate that the transition to phase chaos takes place via a torus destruction process....
4th international interdisciplinary chaos symposium
Banerjee, Santo; Caglar, Suleyman; Ozer, Mehmet; Chaos and complex systems
2013-01-01
Complexity Science and Chaos Theory are fascinating areas of scientific research with wide-ranging applications. The interdisciplinary nature and ubiquity of complexity and chaos are features that provides scientists with a motivation to pursue general theoretical tools and frameworks. Complex systems give rise to emergent behaviors, which in turn produce novel and interesting phenomena in science, engineering, as well as in the socio-economic sciences. The aim of all Symposia on Chaos and Complex Systems (CCS) is to bring together scientists, engineers, economists and social scientists, and to discuss the latest insights and results obtained in the area of corresponding nonlinear-system complex (chaotic) behavior. Especially for the “4th International Interdisciplinary Chaos Symposium on Chaos and Complex Systems,” which took place April 29th to May 2nd, 2012 in Antalya, Turkey, the scope of the symposium had been further enlarged so as to encompass the presentation of work from circuits to econophysic...
Energy Technology Data Exchange (ETDEWEB)
Bunimovich, Leonid A., E-mail: bunimovh@math.gatech.edu [ABC Program, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); School of Mathematics, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States); Vela-Arevalo, Luz V., E-mail: luzvela@math.gatech.edu [School of Mathematics, Georgia Institute of Technology, Atlanta, Georgia 30332 (United States)
2015-09-15
A brief review is presented of some recent findings in the theory of chaotic dynamics. We also prove a statement that could be naturally considered as a dual one to the Poincaré theorem on recurrences. Numerical results demonstrate that some parts of the phase space of chaotic systems are more likely to be visited earlier than other parts. A new class of chaotic focusing billiards is discussed that clearly violates the main condition considered to be necessary for chaos in focusing billiards.
On the Mechanisms Behind Chaos
DEFF Research Database (Denmark)
Lindberg, Erik
2006-01-01
Chaotic systems are observed everywhere. Electronic circuit analogues based on the differential equations of the models for the chaotic systems are often used to study the nature of chaotic systems. This tutorial is an attempt to classify electronic chaotic oscillators according to the mechanism...... behind the chaotic behavior, e.g. one group is based on the sudden interrupt of inductive currents, another group is based on the sudden parallel coupling of capacitors with different voltages, and a third group may be based on multiplication of signals. An example of chaos based on disturbance...
Decoherence, determinism and chaos revisited
Energy Technology Data Exchange (ETDEWEB)
Noyes, H.P.
1994-11-15
We suggest that the derivation of the free space Maxwell Equations for classical electromagnetism, using a discrete ordered calculus developed by L.H. Kauffman and T. Etter, necessarily pushes the discussion of determinism in natural science down to the level of relativistic quantum mechanics and hence renders the mathematical phenomena studied in deterministic chaos research irrelevant to the question of whether the world investigated by physics is deterministic. We believe that this argument reinforces Suppes` contention that the issue of determinism versus indeterminism should be viewed as a Kantian antinomy incapable of investigation using currently available scientific tools.
Thomas, R
2004-01-01
This paper considers questions of transmission and circulation of knowledge between Greeks and Babylonians, and in particular within the medical sphere. It compares evidence for the extensive exchange of goods and ideas with the Near East in the archaic period and considers the channels and means of transmission involved. It suggests, however, that the evidence of Hippocratic medicine and of Herodotus implies that interaction in the medical sphere followed the main areas of contact through trade and colonisation, and above all Egypt, rather than Mesopotamia. Contact with Babylonian wisdom was to reappear only in the late classical and Hellenistic period. PMID:17152173
Quantifying chaos for ecological stoichiometry
Duarte, Jorge; Januário, Cristina; Martins, Nuno; Sardanyés, Josep
2010-09-01
The theory of ecological stoichiometry considers ecological interactions among species with different chemical compositions. Both experimental and theoretical investigations have shown the importance of species composition in the outcome of the population dynamics. A recent study of a theoretical three-species food chain model considering stoichiometry [B. Deng and I. Loladze, Chaos 17, 033108 (2007)] shows that coexistence between two consumers predating on the same prey is possible via chaos. In this work we study the topological and dynamical measures of the chaotic attractors found in such a model under ecological relevant parameters. By using the theory of symbolic dynamics, we first compute the topological entropy associated with unimodal Poincaré return maps obtained by Deng and Loladze from a dimension reduction. With this measure we numerically prove chaotic competitive coexistence, which is characterized by positive topological entropy and positive Lyapunov exponents, achieved when the first predator reduces its maximum growth rate, as happens at increasing δ1. However, for higher values of δ1 the dynamics become again stable due to an asymmetric bubble-like bifurcation scenario. We also show that a decrease in the efficiency of the predator sensitive to prey's quality (increasing parameter ζ) stabilizes the dynamics. Finally, we estimate the fractal dimension of the chaotic attractors for the stoichiometric ecological model.
Chaos suppression through asymmetric coupling
Bragard, J.; Vidal, G.; Mancini, H.; Mendoza, C.; Boccaletti, S.
2007-12-01
We study pairs of identical coupled chaotic oscillators. In particular, we have used Roessler (in the funnel and no funnel regimes), Lorenz, and four-dimensional chaotic Lotka-Volterra models. In all four of these cases, a pair of identical oscillators is asymmetrically coupled. The main result of the numerical simulations is that in all cases, specific values of coupling strength and asymmetry exist that render the two oscillators periodic and synchronized. The values of the coupling strength for which this phenomenon occurs is well below the previously known value for complete synchronization. We have found that this behavior exists for all the chaotic oscillators that we have used in the analysis. We postulate that this behavior is presumably generic to all chaotic oscillators. In order to complete the study, we have tested the robustness of this phenomenon of chaos suppression versus the addition of some Gaussian noise. We found that chaos suppression is robust for the addition of finite noise level. Finally, we propose some extension to this research.
Competitive coexistence in stoichiometric chaos
Deng, Bo; Loladze, Irakli
2007-09-01
Classical predator-prey models, such as Lotka-Volterra, track the abundance of prey, but ignore its quality. Yet, in the past decade, some new and occasionally counterintuitive effects of prey quality on food web dynamics emerged from both experiments and mathematical modeling. The underpinning of this work is the theory of ecological stoichiometry that is centered on the fact that each organism is a mixture of multiple chemical elements such as carbon (C), nitrogen (N), and phosphorus (P). The ratios of these elements can vary within and among species, providing simple ways to represent prey quality as its C:N or C:P ratios. When these ratios modeled to vary, as they frequently do in nature, seemingly paradoxical results can arise such as the extinction of a predator that has an abundant and accessible prey. Here, for the first time, we show analytically that the reduction in prey quality can give rise to chaotic oscillations. In particular, when competing predators differ in their sensitivity to prey quality then all species can coexist via chaotic fluctuations. The chaos generating mechanism is based on the existence of a junction-fold point on the nullcline surfaces of the species. Conditions on parameters are found for such a point, and the singular perturbation method and the kneading sequence analysis are used to demonstrate the existence of a period-doubling cascade to chaos as a result of the point.
Unusual biophysics of intrinsically disordered proteins.
Uversky, Vladimir N
2013-05-01
Research of a past decade and a half leaves no doubt that complete understanding of protein functionality requires close consideration of the fact that many functional proteins do not have well-folded structures. These intrinsically disordered proteins (IDPs) and proteins with intrinsically disordered protein regions (IDPRs) are highly abundant in nature and play a number of crucial roles in a living cell. Their functions, which are typically associated with a wide range of intermolecular interactions where IDPs possess remarkable binding promiscuity, complement functional repertoire of ordered proteins. All this requires a close attention to the peculiarities of biophysics of these proteins. In this review, some key biophysical features of IDPs are covered. In addition to the peculiar sequence characteristics of IDPs these biophysical features include sequential, structural, and spatiotemporal heterogeneity of IDPs; their rough and relatively flat energy landscapes; their ability to undergo both induced folding and induced unfolding; the ability to interact specifically with structurally unrelated partners; the ability to gain different structures at binding to different partners; and the ability to keep essential amount of disorder even in the bound form. IDPs are also characterized by the "turned-out" response to the changes in their environment, where they gain some structure under conditions resulting in denaturation or even unfolding of ordered proteins. It is proposed that the heterogeneous spatiotemporal structure of IDPs/IDPRs can be described as a set of foldons, inducible foldons, semi-foldons, non-foldons, and unfoldons. They may lose their function when folded, and activation of some IDPs is associated with the awaking of the dormant disorder. It is possible that IDPs represent the "edge of chaos" systems which operate in a region between order and complete randomness or chaos, where the complexity is maximal. This article is part of a Special Issue
Nonlinear Dynamics and Chaos: Applications in Atmospheric Sciences
Selvam, A M
2010-01-01
Atmospheric flows, an example of turbulent fluid flows, exhibit fractal fluctuations of all space-time scales ranging from turbulence scale of mm - sec to climate scales of thousands of kilometers - years and may be visualized as a nested continuum of weather cycles or periodicities, the smaller cycles existing as intrinsic fine structure of the larger cycles. The power spectra of fractal fluctuations exhibit inverse power law form signifying long - range correlations identified as self - organized criticality and are ubiquitous to dynamical systems in nature and is manifested as sensitive dependence on initial condition or 'deterministic chaos' in finite precision computer realizations of nonlinear mathematical models of real world dynamical systems such as atmospheric flows. Though the self-similar nature of atmospheric flows have been widely documented and discussed during the last three to four decades, the exact physical mechanism is not yet identified. There now exists an urgent need to develop and inco...
Godfrey, Stephen J; Geisler, Jonathan; Fitzgerald, Erich M G
2013-02-01
The structure of the olfactory apparatus is not well known in both archaic and extant whales; the result of poor preservation in most fossils and locational isolation deep within the skulls in both fossil and Recent taxa. Several specimens now shed additional light on the subject. A partial skull of an archaic cetacean is reported from the Pamunkey River, Virginia, USA. The specimen probably derives from the upper middle Eocene (Piney Point Formation) and is tentatively assigned to the Protocetidae. Uncrushed cranial cavities associated with the olfactory apparatus were devoid of sediment. CT scans clearly reveal the dorsal nasal meatus, ethmoturbinates within the olfactory recess, the cribriform plate, the area occupied by the olfactory bulbs, and the olfactory nerve tract. Several sectioned skulls of the minke whale (Balaenoptera acutorostrata) were also examined, and olfactory structures are remarkably similar to those observed in the fossil skull from the Pamunkey River. One important difference between the two is that the fossil specimen has an elongate olfactory nerve tract. The more forward position of the external nares in extant balaenopterids when compared with those of extant odontocetes is interpreted to be the result of the need to retain a functional olfactory apparatus and the forward position of the supraoccipital/cranial vertex. An increase in the distance between the occipital condyles and the vertex in balaenopterids enhances the mechanical advantage of the epaxial musculature that inserts on the occiput, a specialization that likely stabilizes the head of these enormous mammals during lunge feeding.
Physics and applications of laser diode chaos
Sciamanna, M.; Shore, K. A.
2015-03-01
This Review Article provides an overview of chaos in laser diodes by surveying experimental achievements in the area and explaining the theory behind the phenomenon. The fundamental physics underpinning laser diode chaos and also the opportunities for harnessing it for potential applications are discussed. The availability and ease of operation of laser diodes, in a wide range of configurations, make them a convenient testbed for exploring basic aspects of nonlinear and chaotic dynamics. It also makes them attractive for practical tasks, such as chaos-based secure communications and random number generation. Avenues for future research and development of chaotic laser diodes are also identified.
Chaos dynamic characteristics during mine fires
Institute of Scientific and Technical Information of China (English)
无
2000-01-01
Mine fires break out and continue in confmed scopes, studying mine fire dynamics characteristics is very usefulto prevent and control fire. The judgement index of fire chaos characteristics was introduced, chaos analysis of mine Fireprocess was described, and the reconstruction of phase space was also presented. An example of mine fire was calculated.The computations show that it is feasible to analyze mine fire dynamic characteristics with chaos theory, and indicate thatfire preoeas is a catastrophe, that is to say, the fire system changes from one state to another during mine fire
Chaos from simple models to complex systems
Cencini, Massimo; Vulpiani, Angelo
2010-01-01
Chaos: from simple models to complex systems aims to guide science and engineering students through chaos and nonlinear dynamics from classical examples to the most recent fields of research. The first part, intended for undergraduate and graduate students, is a gentle and self-contained introduction to the concepts and main tools for the characterization of deterministic chaotic systems, with emphasis to statistical approaches. The second part can be used as a reference by researchers as it focuses on more advanced topics including the characterization of chaos with tools of information theor
Chua's circuit a paradigm for chaos
1993-01-01
For uninitiated researchers, engineers, and scientists interested in a quick entry into the subject of chaos, this book offers a timely collection of 55 carefully selected papers covering almost every aspect of this subject. Because Chua's circuit is endowed with virtually every bifurcation phenomena reported in the extensive literature on chaos, and because it is the only chaotic system which can be easily built by a novice, simulated in a personal computer, and tractable mathematically, it has become a paradigm for chaos, and a vehicle for illustrating this ubiquitous phenomenon. Its supreme
Distributed chaos and helicity in turbulence
Bershadskii, A
2016-01-01
The distributed chaos driven by Levich-Tsinober (helicity) integral: $I=\\int \\langle h({\\bf x},t)~h({\\bf x}+{\\bf r}, t)\\rangle d{\\bf r}$ has been studied. It is shown that the helical distributed chaos can be considered as basis for complex turbulent flows with interplay between large-scale coherent structures and small-scale turbulence, such as Cuette-Taylor flow, wake behind cylinder and turbulent flow in the Large Plasma Device (LAPD) with inserted limiters. In the last case appearance of the helical distributed chaos, caused by the limiters, results in improvement of radial particle confinement.
Physics and Applications of Laser Diode Chaos
Sciamanna, Marc
2015-01-01
An overview of chaos in laser diodes is provided which surveys experimental achievements in the area and explains the theory behind the phenomenon. The fundamental physics underpinning this behaviour and also the opportunities for harnessing laser diode chaos for potential applications are discussed. The availability and ease of operation of laser diodes, in a wide range of configurations, make them a convenient test-bed for exploring basic aspects of nonlinear and chaotic dynamics. It also makes them attractive for practical tasks, such as chaos-based secure communications and random number generation. Avenues for future research and development of chaotic laser diodes are also identified.
Dessi, Roberta; Rustichini, Aldo
2015-01-01
A large literature in psychology, and more recently in economics, has argued that monetary rewards can reduce intrinsic motivation. We investigate whether the negative impact persists when intrinsic motivation is strong, and test this hypothesis experimentally focusing on the motivation to undertake interesting and challenging tasks, informative about individual ability. We find that this type of task can generate strong intrinsic motivation, that is impervious to the effect of monetary incen...
Zaheer, Muhammad Hamad; Rehan, Muhammad; Mustafa, Ghulam; Ashraf, Muhammad
2014-11-01
This paper proposes a novel state feedback delay-range-dependent control approach for chaos synchronization in coupled nonlinear time-delay systems. The coupling between two systems is esteemed to be nonlinear subject to time-lags. Time-varying nature of both the intrinsic and the coupling delays is incorporated to broad scope of the present study for a better-quality synchronization controller synthesis. Lyapunov-Krasovskii (LK) functional is employed to derive delay-range-dependent conditions that can be solved by means of the conventional linear matrix inequality (LMI)-tools. The resultant control approach for chaos synchronization of the master-slave time-delay systems considers non-zero lower bound of the intrinsic as well as the coupling time-delays. Further, the delay-dependent synchronization condition has been established as a special case of the proposed LK functional treatment. Furthermore, a delay-range-dependent condition, independent of the delay-rate, has been provided to address the situation when upper bound of the delay-derivative is unknown. A robust state feedback control methodology is formulated for synchronization of the time-delay chaotic networks against the L2 norm bounded perturbations by minimizing the L2 gain from the disturbance to the synchronization error. Numerical simulation results are provided for the time-delay chaotic networks to show effectiveness of the proposed delay-range-dependent chaos synchronization methodologies.
P. Tallapragada; Ross, Shane. D.; Schmale, D. G., III
2011-01-01
Many microorganisms are advected in the lower atmosphere from one habitat to another with scales of motion being hundreds to thousands of kilometers. The concentration of these microbes in the lower atmosphere at a single geographic location can show rapid temporal changes. We used autonomous unmanned aerial vehicles equipped with microbe-sampling devices to collect fungi in the genus Fusarium 100 m above ground level at a single sampling location in Blacksburg, Virginia, USA. Some Fusarium s...
Sándor, Bulcsú; Tél, Tamás; Néda, Zoltán
2013-01-01
The dynamics of a spring-block train placed on a moving conveyor belt is investigated both by simple experiments and computer simulations. The first block is connected by spring to an external static point, and due to the dragging effect of the belt the blocks undergo complex stick-slip dynamics. A qualitative agreement with the experimental results can only be achieved by taking into account the spatial inhomogeneity of the friction force on the belt's surface, modeled as noise. As a function of the velocity of the conveyor belt and the noise strength, the system exhibits complex, self-organized critical, sometimes chaotic dynamics and phase transition-like behavior. Noise induced chaos and intermittency is also observed. Simulations suggest that the maximum complexity of the dynamical states is achieved for a relatively small number of blocks, around five.
Ordered and Disordered Defect Chaos
Granzow, G D; Granzow, Glen D.; Riecke, Hermann
1997-01-01
Defect-chaos is studied numerically in coupled Ginzburg-Landau equations for parametrically driven waves. The motion of the defects is traced in detail yielding their life-times, annihilation partners, and distances traveled. In a regime in which in the one-dimensional case the chaotic dynamics is due to double phase slips, the two-dimensional system exhibits a strongly ordered stripe pattern. When the parity-breaking instability to traveling waves is approached this order vanishes and the correlation function decays rapidly. In the ordered regime the defects have a typical life-time, whereas in the disordered regime the life-time distribution is exponential. The probability of large defect loops is substantially larger in the disordered regime.
Ergodic theory, randomness, and "chaos".
Ornstein, D S
1989-01-13
Ergodic theory is the theory of the long-term statistical behavior of dynamical systems. The baker's transformation is an object of ergodic theory that provides a paradigm for the possibility of deterministic chaos. It can now be shown that this connection is more than an analogy and that at some level of abstraction a large number of systems governed by Newton's laws are the same as the baker's transformation. Going to this level of abstraction helps to organize the possible kinds of random behavior. The theory also gives new concrete results. For example, one can show that the same process could be produced by a mechanism governed by Newton's laws or by a mechanism governed by coin tossing. It also gives a statistical analog of structural stability.
Superfluid (quantum) turbulence and distributed chaos
Bershadskii, A
2016-01-01
Properties of distributed chaos in superfluid (quantum) turbulence have been studied using the data of recent direct numerical simulations (HVBK two-fluid model for He II, and a moving grid in the frames of Gross-Pitaevskii model of the Bose-Einstein condensates at low temperatures). It is found that for the viscous (normal) component of the velocity field in He II the viscosity dominates the distributed chaos with the stretched exponential spectrum $\\exp(-k/k_{\\beta})^{\\beta}$ and $\\beta = 2/3$. For the superfluid component the distributed chaos is dominated by the vorticity correlation integral with $\\beta =1/2$ (the soft spontaneous breaking of the space translational symmetry - homogeneity). For very low temperature the distributed chaos is tuned to the large-scale coherent motions: the viscous (normal) component is tuned to the fundamental mode, whereas the superfluid component is subharmonically tuned. For the Gross-Pitaevskii superfluid turbulence incompressible part of the energy spectrum (containing ...
Symmetry vs. Chaos in collective dynamics
International Nuclear Information System (INIS)
Models of nuclear collective dynamics are used to study the interplay of order (approximate dynamical symmetry) and chaos in general physical systems. We report on some recent results obtained within the interacting boson model and the geometric model. (author)
Detecting nonlinearity and chaos in epidemic data
Energy Technology Data Exchange (ETDEWEB)
Ellner, S.; Gallant, A.R. [North Carolina State Univ., Raleigh, NC (United States). Dept. of Statistics; Theiler, J. [Santa Fe Inst., NM (United States)]|[Los Alamos National Lab., NM (United States)
1993-08-01
Historical data on recurrent epidemics have been central to the debate about the prevalence of chaos in biological population dynamics. Schaffer and Kot who first recognized that the abundance and accuracy of disease incidence data opened the door to applying a range of methods for detecting chaos that had been devised in the early 1980`s. Using attractor reconstruction, estimates of dynamical invariants, and comparisons between data and simulation of SEIR models, the ``case for chaos in childhood epidemics`` was made through a series of influential papers beginning in the mid 1980`s. The proposition that the precise timing and magnitude of epidemic outbreaks are deterministic but chaotic is appealing, since it raises the hope of finding determinism and simplicity beneath the apparently stochastic and complicated surface of the data. The initial enthusiasm for methods of detecting chaos in data has been followed by critical re-evaluations of their limitations. Early hopes of a ``one size fits all`` algorithm to diagnose chaos vs. noise in any data set have given way to a recognition that a variety of methods must be used, and interpretation of results must take into account the limitations of each method and the imperfections of the data. Our goals here are to outline some newer methods for detecting nonlinearity and chaos that have a solid statistical basis and are suited to epidemic data, and to begin a re-evaluation of the claims for nonlinear dynamics and chaos in epidemics using these newer methods. We also identify features of epidemic data that create problems for the older, better known methods of detecting chaos. When we ask ``are epidemics nonlinear?``, we are not questioning the existence of global nonlinearities in epidemic dynamics, such as nonlinear transmission rates. Our question is whether the data`s deviations from an annual cyclic trend (which would reflect global nonlinearities) are described by a linear, noise-driven stochastic process.
Legal System and Legal Chaos Theory
Directory of Open Access Journals (Sweden)
Amir Syarifudin
2015-08-01
Full Text Available Order of the universe and other objects can be described either by cosmology and physics. But from of the regularity of the object there in terms or aspect of irregularity or fractal (broken that difficult to describe by Auklides and Calculus mathematical models. Benoit Medelbrot tried to explain the chaotic objects with fractal theory which basically a branch of mathematics. The fractal theory affect the view of the law that inspired Charles Sampford which then sparked a legal chaos theory. The core of legal chaos theory is (1 social relationships , including the relationship established based on the relationship of forces (power relation, (2 the parties who make that relationship does not have the same strength or balance, and (3 at the time of execution of the respective relations based on their subjective opinions. Those three thing that is causing chaos. But the atmosphere of chaos that would eventually return to the regularity, because of the strength towing (strange attractor that in the area of law is the law and the power of the state. Chaos basically contained in the freedom -based relationship beyond the confines of order. When the towing force managed to recover the chaos so as to create harmony between order and freedom, the peace that one of the legal goal is achieved.
Directory of Open Access Journals (Sweden)
Camilo Rubén Fernández-Cozman
2016-07-01
Full Text Available This article holds that there is a radical ethnocentrism in two essays of Mario Vargas Llosa, Archaic Utopia and Civilization of the Show. In this regard, the Peruvian writer does not recognize a mythical rationality and conceived that legal culture is superior to oral culture.
Directory of Open Access Journals (Sweden)
Eko Haryono
2013-07-01
Full Text Available The Plaosan Temple which was built during the eighth and tenth century AD is one of four temple complexes in the Prambanan area, Central Java-Indonesia. On going excavation in the temple complex discloses the occurrence of canals along the outer fences. The canals are eight meters wide and four meters deep. This article aims at reconstructing archaic river course and groundwater condition due to the construction of the canals. Aerial photo interpretation, excavation, ground water level measurement and valley morphology measurement reveal an anomaly of the nearest river in the temple complex. The river had seemingly been bypassed south-eastward to its tributary just before entering Plaosan Temple complex. Groundwater level dropped and its flow direction changed from nearly southward to south-eastward direction. These phenomena indicate that the canals were groundwater-discharged canals.
Genome chaos: survival strategy during crisis.
Liu, Guo; Stevens, Joshua B; Horne, Steven D; Abdallah, Batoul Y; Ye, Karen J; Bremer, Steven W; Ye, Christine J; Chen, David J; Heng, Henry H
2014-01-01
Genome chaos, a process of complex, rapid genome re-organization, results in the formation of chaotic genomes, which is followed by the potential to establish stable genomes. It was initially detected through cytogenetic analyses, and recently confirmed by whole-genome sequencing efforts which identified multiple subtypes including "chromothripsis", "chromoplexy", "chromoanasynthesis", and "chromoanagenesis". Although genome chaos occurs commonly in tumors, both the mechanism and detailed aspects of the process are unknown due to the inability of observing its evolution over time in clinical samples. Here, an experimental system to monitor the evolutionary process of genome chaos was developed to elucidate its mechanisms. Genome chaos occurs following exposure to chemotherapeutics with different mechanisms, which act collectively as stressors. Characterization of the karyotype and its dynamic changes prior to, during, and after induction of genome chaos demonstrates that chromosome fragmentation (C-Frag) occurs just prior to chaotic genome formation. Chaotic genomes seem to form by random rejoining of chromosomal fragments, in part through non-homologous end joining (NHEJ). Stress induced genome chaos results in increased karyotypic heterogeneity. Such increased evolutionary potential is demonstrated by the identification of increased transcriptome dynamics associated with high levels of karyotypic variance. In contrast to impacting on a limited number of cancer genes, re-organized genomes lead to new system dynamics essential for cancer evolution. Genome chaos acts as a mechanism of rapid, adaptive, genome-based evolution that plays an essential role in promoting rapid macroevolution of new genome-defined systems during crisis, which may explain some unwanted consequences of cancer treatment.
CHAOS III: Gas-Phase Abundances in NGC5457
Croxall, Kevin; Berg, Danielle A; Skillman, Evan D; Moustakas, John
2016-01-01
The CHemical Abundances of Spirals (CHAOS) project leverages the combined power of the Large Binocular Telescope with the broad spectral range and sensitivity of the Multi Object Double Spectrograph (MODS) to measure direct abundances in large samples of HII regions in spiral galaxies. We present LBT MODS observations of 109 Hii regions in NGC5457, of which 74 have robust measurements of key auroral lines, a factor of 3 larger than all previous published detections of auroral lines in the HII regions of NGC5457. Comparing the temperatures derived from the different ionic species we find: (1) strong correlations of T[NII] with T[SIII] and T[OIII], consistent with little or no intrinsic scatter; (2) a correlation of T[SIII] with T[OIII], but with significant intrinsic dispersion; (3) overall agreement between T[NII], T[SII], and T[OII], as expected, but with significant outliers; (4) the correlations of T[NII] with T[SIII] and T[OIII] match the predictions of photoionization modeling while the correlation of T[...
Murakami, Shuichi
2005-01-01
A brief review is given on the spin Hall effect, where an external electric field induces a transverse spin current. It has been recognized over 30 years that such effect occurs due to impurities in the presence of spin-orbit coupling. Meanwhile, it was proposed recently that there is also an intrinsic contribution for this effect. We explain the mechanism for this intrinsic spin Hall effect. We also discuss recent experimental observations of the spin Hall effect.
Truc Le
2014-01-01
We review the nature of some well-known phenomena such as volatility smiles, convexity adjustments and parallel derivative markets. We propose that the market is incomplete and postulate the existence of intrinsic risks in every contingent claim as a basis for understanding these phenomena. In a continuous time framework, we bring together the notion of intrinsic risk and the theory of change of measures to derive a probability measure, namely risk-subjective measure, for evaluating contingen...
Quantum chaos in nanoelectromechanical systems
Gusso, André; da Luz, M. G. E.; Rego, Luis G. C.
2006-01-01
We present a theoretical study of the electron-phonon coupling in suspended nanoelectromechanical systems and investigate the resulting quantum chaotic behavior. The phonons are associated with the vibrational modes of a suspended rectangular dielectric plate, with free or clamped boundary conditions, whereas the electrons are confined to a large quantum dot (QD) on the plate’s surface. The deformation potential and piezoelectric interactions are considered. By performing standard energy-level statistics we demonstrate that the spectral fluctuations exhibit the same distributions as those of the Gaussian orthogonal ensemble or the Gaussian unitary ensemble (GUE), therefore evidencing the emergence of quantum chaos. That is verified for a large range of material and geometry parameters. In particular, the GUE statistics occurs only in the case of a circular QD. It represents an anomalous phenomenon, previously reported for just a small number of systems, since the problem is time-reversal invariant. The obtained results are explained through a detailed analysis of the Hamiltonian matrix structure.
Regularly timed events amid chaos
Blakely, Jonathan N.; Cooper, Roy M.; Corron, Ned J.
2015-11-01
We show rigorously that the solutions of a class of chaotic oscillators are characterized by regularly timed events in which the derivative of the solution is instantaneously zero. The perfect regularity of these events is in stark contrast with the well-known unpredictability of chaos. We explore some consequences of these regularly timed events through experiments using chaotic electronic circuits. First, we show that a feedback loop can be implemented to phase lock the regularly timed events to a periodic external signal. In this arrangement the external signal regulates the timing of the chaotic signal but does not strictly lock its phase. That is, phase slips of the chaotic oscillation persist without disturbing timing of the regular events. Second, we couple the regularly timed events of one chaotic oscillator to those of another. A state of synchronization is observed where the oscillators exhibit synchronized regular events while their chaotic amplitudes and phases evolve independently. Finally, we add additional coupling to synchronize the amplitudes, as well, however in the opposite direction illustrating the independence of the amplitudes from the regularly timed events.
2nd International Symposium on Chaos, Complexity and Leadership
Banerjee, Santo
2015-01-01
These proceedings from the 2013 symposium on "Chaos, complexity and leadership" reflect current research results from all branches of Chaos, Complex Systems and their applications in Management. Included are the diverse results in the fields of applied nonlinear methods, modeling of data and simulations, as well as theoretical achievements of Chaos and Complex Systems. Also highlighted are Leadership and Management applications of Chaos and Complexity Theory.
The Capabilities of Chaos and Complexity
Directory of Open Access Journals (Sweden)
David L. Abel
2009-01-01
Full Text Available To what degree could chaos and complexity have organized a Peptide or RNA World of crude yet necessarily integrated protometabolism? How far could such protolife evolve in the absence of a heritable linear digital symbol system that could mutate, instruct, regulate, optimize and maintain metabolic homeostasis? To address these questions, chaos, complexity, self-ordered states, and organization must all be carefully defined and distinguished. In addition their cause-and-effect relationships and mechanisms of action must be delineated. Are there any formal (non physical, abstract, conceptual, algorithmic components to chaos, complexity, self-ordering and organization, or are they entirely physicodynamic (physical, mass/energy interaction alone? Chaos and complexity can produce some fascinating self-ordered phenomena. But can spontaneous chaos and complexity steer events and processes toward pragmatic benefit, select function over non function, optimize algorithms, integrate circuits, produce computational halting, organize processes into formal systems, control and regulate existing systems toward greater efficiency? The question is pursued of whether there might be some yet-to-be discovered new law of biology that will elucidate the derivation of prescriptive information and control. Ã¢Â€ÂœSystemÃ¢Â€Â will be rigorously defined. Can a low-informational rapid succession of PrigogineÃ¢Â€Â™s dissipative structures self-order into bona fide organization?
Reliable Computational Predictions by Modeling Uncertainties Using Arbitrary Polynomial Chaos
Witteveen, J.A.S.; Bijl, H
2006-01-01
Inherent physical uncertainties can have a significant influence on computational predictions. It is therefore important to take physical uncertainties into account to obtain more reliable computational predictions. The Galerkin polynomial chaos method is a commonly applied uncertainty quantification method. However, the polynomial chaos expansion has some limitations. Firstly, the polynomial chaos expansion based on classical polynomials can achieve exponential convergence for a limited set ...
God's Stuff: The Constructive Powers of Chaos for Teaching Religion
Willhauck, Susan
2010-01-01
Order and organization are valued in the classroom, and there is a prevailing understanding that chaos should be avoided. Yet chaos can also be potent space or a source from which new things spring forth. This article investigates biblical, scientific, and cultural understandings of chaos to discover how these contribute to a revelatory metaphor…
FRUSTRATION EFFECT ON SYNCHRONIZATION AND CHAOS IN COUPLED OSCILLATORS
Institute of Scientific and Technical Information of China (English)
ZHENG ZHI-GANG
2001-01-01
Synchronization dynamics in an array of coupled periodic oscillators with quenched natural frequencies are discussed in the presence of homogeneous phase shifts (frustrations). Frustration-induced desynchronization and chaos are found. The torus-doubling route to chaos, toroidal chaos and torus crisis are investigated.
Emergence of integer quantum Hall effect from chaos
Tian, Chushun; Chen, Yu; Wang, Jiao
2016-02-01
We present an analytic microscopic theory showing that in a large class of spin-1/2 quasiperiodic quantum kicked rotors, a dynamical analog of the integer quantum Hall effect (IQHE) emerges from an intrinsic chaotic structure. Specifically, the inverse of the Planck's quantum (he) and the rotor's energy growth rate mimic the "filling fraction" and the "longitudinal conductivity" in conventional IQHE, respectively, and a hidden quantum number is found to mimic the "quantized Hall conductivity." We show that for an infinite discrete set of critical values of he, the long-time energy growth rate is universal and of order of unity ("metallic" phase), but otherwise vanishes ("insulating" phase). Moreover, the rotor insulating phases are topological, each of which is characterized by a hidden quantum number. This number exhibits universal behavior for small he, i.e., it jumps by unity whenever he decreases, passing through each critical value. This intriguing phenomenon is not triggered by the likes of Landau band filling, well known to be the mechanism for conventional IQHE, and far beyond the canonical Thouless-Kohmoto-Nightingale-Nijs paradigm for quantum Hall transitions. Instead, this dynamical phenomenon is of strong chaos origin; it does not occur when the dynamics is (partially) regular. More precisely, we find that a topological object, similar to the topological theta angle in quantum chromodynamics, emerges from strongly chaotic motion at microscopic scales, and its renormalization gives the hidden quantum number. Our analytic results are confirmed by numerical simulations. Our findings indicate that rich topological quantum phenomena can emerge from chaos and might point to a new direction of study in the interdisciplinary area straddling chaotic dynamics and condensed matter physics. This work is a substantial extension of a short paper published earlier by two of us [Y. Chen and C. Tian, Phys. Rev. Lett. 113, 216802 (2014), 10.1103/PhysRevLett.113.216802].
Chaos Concepts, Control and Constructive Use
Bolotin, Yurii; Yanovsky, Vladimir
2009-01-01
The study of chaotic behaviour in nonlinear, dynamical systems is now a well established research domain with ramifications into all fields of sciences, spanning a vast range of applications, from celestial mechanics, via climate change, to the functioning of brownian motors in cells. A more recent discovery is that chaos can be controlled and, under appropriate conditions, can actually be constructive in the sense of becoming a control parameter itself for the system under investigation, stochastic resonance being a prime example. The present work is putting emphasis on the latter aspects, and after recalling the paradigm changes introduced by the concept of chaos, leads the reader skillfully through the basics of chaos control by detailing relevant algorithms for both Hamiltonian and dissipative systems amongst others. The main part of the book is then devoted to the issue of synchronization in chaotic systems, an introduction to stochastic resonance and a survey of ratchet models. This short and concise pr...
Avoiding Quantum Chaos in Quantum Computation
Berman, G P; Izrailev, F M; Tsifrinovich, V I
2001-01-01
We study a one-dimensional chain of nuclear $1/2-$spins in an external time-dependent magnetic field. This model is considered as a possible candidate for experimental realization of quantum computation. According to the general theory of interacting particles, one of the most dangerous effects is quantum chaos which can destroy the stability of quantum operations. According to the standard viewpoint, the threshold for the onset of quantum chaos due to an interaction between spins (qubits) strongly decreases with an increase of the number of qubits. Contrary to this opinion, we show that the presence of a magnetic field gradient helps to avoid quantum chaos which turns out to disappear with an increase of the number of qubits. We give analytical estimates which explain this effect, together with numerical data supporting
Associative memory with spatiotemporal chaos control
Kushibe, Masanori; Liu, Yun; Ohtsubo, Junji
1996-05-01
Control of spatiotemporal chaos in a neural network with discrete time and continuous state variables is investigated. The chaos control is performed with the knowledge of only a part of the target information in the memory patterns. The success rate for the pattern associations and the dependence of the search time on the sampling number in the proposed chaos neural network are studied. By the introduction of the reinforcement factor in the learning process, the recognition rate of the network can be much enhanced. Random and regular samplings of the pattern for the control are tested and the successful results of the associations are demonstrated. The chaotic behavior and recalling ability of the system are evaluated based on the analysis of the Lyapunov spectrum of the network.
Towards CHAOS-5 - How can Swarm contribute?
DEFF Research Database (Denmark)
Finlay, Chris; Olsen, Nils; Tøffner-Clausen, Lars
2014-01-01
The launch of ESA's satellite trio Swarm in November 2013 opens an exciting new chapter in the observation and monitoring of Earth's magnetic field from space. We report preliminary results from an extension of the CHAOS series of geomagnetic field models to include both scalar and vector field...... observations from the three Swarm satellites, along with the most recent quasi-definitive ground observatory data. The fit of this new update CHAOS field model to the Swarm observations will be presented in detail providing useful insight the initial Swarm data. Enhancements of the CHAOS modelling scheme...... include a 1 minute time resolution for the RC index and anisotropic weighting of vector field data depending on quasi-dipole latitude. We shall also report on the perspective given by the initial Swarm data on rapid field changes currently taking place in the Atlantic sector....
Nonlinear dynamics and quantum chaos an introduction
Wimberger, Sandro
2014-01-01
The field of nonlinear dynamics and chaos has grown very much over the last few decades and is becoming more and more relevant in different disciplines. This book presents a clear and concise introduction to the field of nonlinear dynamics and chaos, suitable for graduate students in mathematics, physics, chemistry, engineering, and in natural sciences in general. It provides a thorough and modern introduction to the concepts of Hamiltonian dynamical systems' theory combining in a comprehensive way classical and quantum mechanical description. It covers a wide range of topics usually not found in similar books. Motivations of the respective subjects and a clear presentation eases the understanding. The book is based on lectures on classical and quantum chaos held by the author at Heidelberg University. It contains exercises and worked examples, which makes it ideal for an introductory course for students as well as for researchers starting to work in the field.
Chaos in periodically forced Holling type IV predator-prey system with impulsive perturbations
International Nuclear Information System (INIS)
The effect of periodic forcing and impulsive perturbations on predator-prey model with Holling type IV functional response is investigated. The periodic forcing is affected by assuming a periodic variation in the intrinsic growth rate of the prey. The impulsive perturbations are affected by introducing periodic constant impulsive immigration of predator. The dynamical behavior of the system is simulated and bifurcation diagrams are obtained for different parameters. The results show that periodic forcing and impulsive perturbation can easily give rise to complex dynamics, including (1) quasi-periodic oscillating, (2) period doubling cascade, (3) chaos, (4) period halfing cascade
Chaos in periodically forced Holling type II predator-prey system with impulsive perturbations
International Nuclear Information System (INIS)
The effect of periodic forcing and impulsive perturbations on predator-prey model with Holling type II functional response is investigated. The periodic forcing is affected by assuming a periodic variation in the intrinsic growth rate of prey. The impulsive perturbation is affected by introducing periodic constant impulsive immigration of predator. The dynamical behavior of the system is simulated and bifurcation diagrams are obtained for different parameters. The results show that periodic forcing and impulsive perturbation can very easily give rise to complex dynamics, including (1) quasi-periodic oscillating, (2) period doubling cascade, (3) chaos, (4) period halfing cascade, (5) non-unique dynamics
Ventilatory chaos is impaired in carotid atherosclerosis.
Directory of Open Access Journals (Sweden)
Laurence Mangin
Full Text Available Ventilatory chaos is strongly linked to the activity of central pattern generators, alone or influenced by respiratory or cardiovascular afferents. We hypothesized that carotid atherosclerosis should alter ventilatory chaos through baroreflex and autonomic nervous system dysfunctions. Chaotic dynamics of inspiratory flow was prospectively evaluated in 75 subjects undergoing carotid ultrasonography: 27 with severe carotid stenosis (>70%, 23 with moderate stenosis (<70%, and 25 controls. Chaos was characterized by the noise titration method, the correlation dimension and the largest Lyapunov exponent. Baroreflex sensitivity was estimated in the frequency domain. In the control group, 92% of the time series exhibit nonlinear deterministic chaos with positive noise limit, whereas only 68% had a positive noise limit value in the stenoses groups. Ventilatory chaos was impaired in the groups with carotid stenoses, with significant parallel decrease in the noise limit value, correlation dimension and largest Lyapunov exponent, as compared to controls. In multiple regression models, the percentage of carotid stenosis was the best in predicting the correlation dimension (p<0.001, adjusted R(2: 0.35 and largest Lyapunov exponent (p<0.001, adjusted R(2: 0.6. Baroreflex sensitivity also predicted the correlation dimension values (p = 0.05, and the LLE (p = 0.08. Plaque removal after carotid surgery reversed the loss of ventilatory complexity. To conclude, ventilatory chaos is impaired in carotid atherosclerosis. These findings depend on the severity of the stenosis, its localization, plaque surface and morphology features, and is independently associated with baroreflex sensitivity reduction. These findings should help to understand the determinants of ventilatory complexity and breathing control in pathological conditions.
Chaos, brain and divided consciousness.
Bob, Petr
2007-01-01
Modern trends in psychology and cognitive neuroscience suggest that applications of nonlinear dynamics, chaos and self-organization seem to be particularly important for research of some fundamental problems regarding mind-brain relationship. Relevant problems among others are formations of memories during alterations of mental states and nature of a barrier that divides mental states, and leads to the process called dissociation. This process is related to a formation of groups of neurons which often synchronize their firing patterns in a unique spatial maner. Central theme of this study is the relationship between level of moving and oscilating mental processes and their neurophysiological substrate. This opens a question about principles of organization of conscious experiences and how these experiences arise in the brain. Chaotic self-organization provides a unique theoretical and experimental tool for deeper understanding of dissociative phenomena and enables to study how dissociative phenomena can be linked to epileptiform discharges which are related to various forms of psychological and somatic manifestations. Organizing principles that constitute human consciousness and other mental phenomena from this point of view may be described by analysis and reconstruction of underlying dynamics of psychological or psychophysiological measures. These nonlinear methods in this study were used for analysis of characteristic changes in EEG and bilateral electrodermal activity (EDA) during reliving of dissociated traumatic and stressful memories and during psychopathological states. Analysis confirms a possible role of chaotic transitions in the processing of dissociated memory. Supportive finding for a possible chaotic process related to dissociation found in this study represent also significant relationship of dissociation, epileptiform discharges measured by typical psychopathological manifestations and characteristic laterality changes in bilateral EDA in patients
Chaos in an imperfectly premixed model combustor
Energy Technology Data Exchange (ETDEWEB)
Kabiraj, Lipika, E-mail: lipika.kabiraj@tu-berlin.de; Saurabh, Aditya; Paschereit, Christian O. [Hermann Föttinger Institut, Technische Universität Berlin (Germany); Karimi, Nader [School of Engineering, University of Glasgow (United Kingdom); Sailor, Anna [University of Wisconsin-Madison, Madison 53706 (United States); Mastorakos, Epaminondas; Dowling, Ann P. [Department of Engineering, University of Cambridge (United Kingdom)
2015-02-15
This article reports nonlinear bifurcations observed in a laboratory scale, turbulent combustor operating under imperfectly premixed mode with global equivalence ratio as the control parameter. The results indicate that the dynamics of thermoacoustic instability correspond to quasi-periodic bifurcation to low-dimensional, deterministic chaos, a route that is common to a variety of dissipative nonlinear systems. The results support the recent identification of bifurcation scenarios in a laminar premixed flame combustor (Kabiraj et al., Chaos: Interdiscip. J. Nonlinear Sci. 22, 023129 (2012)) and extend the observation to a practically relevant combustor configuration.
Atoms in static fields Chaos or Diffraction?
Dando, P A
1998-01-01
A brief review of the manifestations of classical chaos observed in atomic systems is presented. Particular attention is paid to the analysis of atomic spectra by periodic orbit-type theories. For diamagnetic non-hydrogenic Rydberg atoms, the dynamical explanation for observed spectral features has been disputed. By building on our previous work on the photoabsorption spectrum, we show how, by the addition of diffractive terms, the spectral fluctuations in the energy level spectrum of general Rydberg atoms can be obtained with remarkable precision from the Gutzwiller trace formula. This provides further evidence that non-hydrogenic systems are most naturally described in terms of diffraction rather than classical chaos.
Distributed chaos and inertial ranges in turbulence
Bershadskii, A
2016-01-01
It is shown that appearance of inertial range of scales, adjacent to distributed chaos range, results in adiabatic invariance of an energy correlation integral for isotropic homogeneous turbulence and for buoyancy driven turbulence (with stable or unstable stratification, including Rayleigh-Taylor mixing zone). Power spectrum of velocity field for distributed chaos dominated by this adiabatic invariant has a stretched exponential form $\\propto \\exp(-k/k_{\\beta})^{3/5}$. Results of recent direct numerical simulations have been used in order to support these conclusions.
Quantum chaos on a critical Fermi surface
Patel, Aavishkar A
2016-01-01
We compute parameters characterizing many-body quantum chaos for a critical Fermi surface without quasiparticle excitations. We examine a theory of $N$ species of fermions at non-zero density coupled to a $U(1)$ gauge field in two spatial dimensions, and determine the Lyapunov rate and the butterfly velocity in an extended RPA approximation. The thermal diffusivity is found to be universally related to these chaos parameters, i.e. the relationship is independent of $N$, the gauge coupling constant, the Fermi velocity, the Fermi surface curvature, and high energy details.
Controlling chaos in an economic model
Chen, Liang; Chen, Guanrong
2007-01-01
A Cournot duopoly, with a bounded inverse demand function and different constant marginal production costs, can be modeled as a discrete-time dynamical system, which exhibits complex bifurcating and chaotic behaviors. Based on some essential features of the model, we show how bifurcation and chaos can be controlled via the delayed feedback control method. We then propose and evaluate an adaptive parameter-tuning algorithm for control. In addition, we discuss possible economic implications of the chaos control strategies described in the paper.
USING OPTIMAL FEEDBACK CONTROL FOR CHAOS TARGETING
Institute of Scientific and Technical Information of China (English)
PENG ZHAO-WANG; ZHONG TING-XIU
2000-01-01
Since the conventional open-loop optimal targeting of chaos is very sensitive to noise, a close-loop optimal targeting method is proposed to improve the targeting performance under noise. The present optimal targeting model takes into consideration both precision and speed of the targeting procedure. The parameters, rather than the output, of the targeting controller, are directly optimized to obtain optimal chaos targeting. Analysis regarding the mechanism is given from physics aspect and numerical experiment on the Hénon map is carried out to compare the targeting performance under noise between the close-loop and the open-loop methods.
Lorentz invariant intrinsic decoherence
Milburn, G J
2003-01-01
Quantum decoherence can arise due to classical fluctuations in the parameters which define the dynamics of the system. In this case decoherence, and complementary noise, is manifest when data from repeated measurement trials are combined. Recently a number of authors have suggested that fluctuations in the space-time metric arising from quantum gravity effects would correspond to a source of intrinsic noise, which would necessarily be accompanied by intrinsic decoherence. This work extends a previous heuristic modification of Schr\\"{o}dinger dynamics based on discrete time intervals with an intrinsic uncertainty. The extension uses unital semigroup representations of space and time translations rather than the more usual unitary representation, and does the least violence to physically important invariance principles. Physical consequences include a modification of the uncertainty principle and a modification of field dispersion relations, in a way consistent with other modifications suggested by quantum grav...
Phase Chaos and Multistability in the Discrete Kuramoto Model
DEFF Research Database (Denmark)
Maistrenko, V. L.; Vasylenko, A. A.; Maistrenko, Y. L.;
2008-01-01
The paper describes the appearance of a novel high-dimensional chaotic regime, called phase chaos, in the discrete Kuramoto model of globally coupled phase oscillators. This type of chaos is observed at small and intermediate values of the coupling strength. It is caused by the nonlinear...... interaction of the oscillators, while the individual oscillators behave periodically when left uncoupled. For the four-dimensional discrete Kuramoto model, we outline the region of phase chaos in the parameter plane, distinguish the region where the phase chaos coexists with other periodic attractors......, and demonstrate, in addition, that the transition to the phase chaos takes place through the torus destruction scenario....
Intrinsic Time Quantum Geometrodynamics
Ita, Eyo Eyo; Yu, Hoi-Lai
2015-01-01
Quantum Geometrodynamics with intrinsic time development and momentric variables is presented. An underlying SU(3) group structure at each spatial point regulates the theory. The intrinsic time behavior of the theory is analyzed, together with its ground state and primordial quantum fluctuations. Cotton-York potential dominates at early times when the universe was small; the ground state naturally resolves Penrose's Weyl Curvature Hypothesis, and thermodynamic and gravitational `arrows of time' point in the same direction. Ricci scalar potential corresponding to Einstein's General Relativity emerges as a zero-point energy contribution. A new set of fundamental canonical commutation relations without Planck's constant emerges from the unification of Gravitation and Quantum Mechanics.
Directory of Open Access Journals (Sweden)
Thomas C. Hart
2013-09-01
Full Text Available Early Archaic subsistence strategies of New England remain poorly understood despite their importance in helping researchers understand how people adapt to changing landscapes following the end of the last glacial maximum (21,000-14,000 B.P.. Excavations at the Mashantucket Pequot Reservation in Mashantucket, Connecticut during the 1990s revealed a large, semi-sedentary village nestled alongside a complex wetland ecosystem. In this paper, we present preliminary starch grain analysis of several stone tools recovered and curated from these excavations. The results of this study indicate that both transitory and reserve starch grains are preserved on these artifacts and that at least one of the artifacts may have been used for leaf or stem processing. The results of this study also demonstrate the potential for future research in which paired macrobotanical and residue analysis will allow for a better understanding of subsistence practices at the site and during the early Archaic in general.
Predicting Intrinsic Motivation
Martens, Rob; Kirschner, Paul A.
2004-01-01
Intrinsic motivation can be predicted from participants' perceptions of the social environment and the task environment (Ryan & Deci, 2000)in terms of control, relatedness and competence. To determine the degree of independence of these factors 251 students in higher vocational education (physiotherapy and hotel management) indicated the extent to…
Chaos: A Very Short Introduction
International Nuclear Information System (INIS)
This book is a new volume of a series designed to introduce the curious reader to anything from ancient Egypt and Indian philosophy to conceptual art and cosmology. Very handy in pocket size, Chaos promises an introduction to fundamental concepts of nonlinear science by using mathematics that is 'no more complicated than X=2. Anyone who ever tried to give a popular science account of research knows that this is a more challenging task than writing an ordinary research article. Lenny Smith brilliantly succeeds to explain in words, in pictures and by using intuitive models the essence of mathematical dynamical systems theory and time series analysis as it applies to the modern world. In a more technical part he introduces the basic terms of nonlinear theory by means of simple mappings. He masterly embeds this analysis into the social, historical and cultural context by using numerous examples, from poems and paintings over chess and rabbits to Olbers' paradox, card games and 'phynance'. Fundamental problems of the modelling of nonlinear systems like the weather, sun spots or golf balls falling through an array of nails are discussed from the point of view of mathematics, physics and statistics by touching upon philosophical issues. At variance with Laplace's demon, Smith's 21st century demon makes 'real world' observations only with limited precision. This poses a severe problem to predictions derived from complex chaotic models, where small variations of initial conditions typically yield totally different outcomes. As Smith argues, this difficulty has direct implications on decision-making in everyday modern life. However, it also asks for an inherently probabilistic theory, which somewhat reminds us of what we are used to in the microworld. There is little to criticise in this nice little book except that some figures are of poor quality thus not really reflecting the beauty of fractals and other wonderful objects in this field. I feel that occasionally the book
Chaos: A Very Short Introduction
Energy Technology Data Exchange (ETDEWEB)
Klages, R [School of Mathematical Sciences, Mile End Road, London, E1 4NS (United Kingdom)
2007-07-20
This book is a new volume of a series designed to introduce the curious reader to anything from ancient Egypt and Indian philosophy to conceptual art and cosmology. Very handy in pocket size, Chaos promises an introduction to fundamental concepts of nonlinear science by using mathematics that is 'no more complicated than X=2. Anyone who ever tried to give a popular science account of research knows that this is a more challenging task than writing an ordinary research article. Lenny Smith brilliantly succeeds to explain in words, in pictures and by using intuitive models the essence of mathematical dynamical systems theory and time series analysis as it applies to the modern world. In a more technical part he introduces the basic terms of nonlinear theory by means of simple mappings. He masterly embeds this analysis into the social, historical and cultural context by using numerous examples, from poems and paintings over chess and rabbits to Olbers' paradox, card games and 'phynance'. Fundamental problems of the modelling of nonlinear systems like the weather, sun spots or golf balls falling through an array of nails are discussed from the point of view of mathematics, physics and statistics by touching upon philosophical issues. At variance with Laplace's demon, Smith's 21st century demon makes 'real world' observations only with limited precision. This poses a severe problem to predictions derived from complex chaotic models, where small variations of initial conditions typically yield totally different outcomes. As Smith argues, this difficulty has direct implications on decision-making in everyday modern life. However, it also asks for an inherently probabilistic theory, which somewhat reminds us of what we are used to in the microworld. There is little to criticise in this nice little book except that some figures are of poor quality thus not really reflecting the beauty of fractals and other wonderful objects in this
Quantum dynamical entropies in discrete classical chaos
Energy Technology Data Exchange (ETDEWEB)
Benatti, Fabio [Dipartimento di Fisica Teorica, Universita di Trieste, Strada Costiera 11, 34014 Trieste (Italy); Cappellini, Valerio [Dipartimento di Fisica Teorica, Universita di Trieste, Strada Costiera 11, 34014 Trieste (Italy); Zertuche, Federico [Instituto de Matematicas, UNAM, Unidad Cuernavaca, AP 273-3, Admon. 3, 62251 Cuernavaca, Morelos (Mexico)
2004-01-09
We discuss certain analogies between quantization and discretization of classical systems on manifolds. In particular, we will apply the quantum dynamical entropy of Alicki and Fannes to numerically study the footprints of chaos in discretized versions of hyperbolic maps on the torus.
Chaos in the Belousov-Zhabotinsky reaction
Field, Richard J.
The dynamics of reacting chemical systems is governed by typically polynomial differential equations that may contain nonlinear terms and/or embedded feedback loops. Thus the dynamics of such systems may exhibit features associated with nonlinear dynamical systems, including (among others): temporal oscillations, excitability, multistability, reaction-diffusion-driven formation of spatial patterns, and deterministic chaos. These behaviors are exhibited in the concentrations of intermediate chemical species. Bifurcations occur between particular dynamic behaviors as system parameters are varied. The governing differential equations of reacting chemical systems have as variables the concentrations of all chemical species involved, as well as controllable parameters, including temperature, the initial concentrations of all chemical species, and fixed reaction-rate constants. A discussion is presented of the kinetics of chemical reactions as well as some thermodynamic considerations important to the appearance of temporal oscillations and other nonlinear dynamic behaviors, e.g., deterministic chaos. The behavior, chemical details, and mechanism of the oscillatory Belousov-Zhabotinsky Reaction (BZR) are described. Furthermore, experimental and mathematical evidence is presented that the BZR does indeed exhibit deterministic chaos when run in a flow reactor. The origin of this chaos seems to be in toroidal dynamics in which flow-driven oscillations in the control species bromomalonic acid couple with the BZR limit cycle...
Chaos control applied to heart rhythm dynamics
Energy Technology Data Exchange (ETDEWEB)
Borem Ferreira, Bianca, E-mail: biaborem@gmail.com [Universidade Federal do Rio de Janeiro, COPPE, Department of Mechanical Engineering, P.O. Box 68.503, 21.941.972 Rio de Janeiro, RJ (Brazil); Souza de Paula, Aline, E-mail: alinedepaula@unb.br [Universidade de Brasi' lia, Department of Mechanical Engineering, 70.910.900 Brasilia, DF (Brazil); Amorim Savi, Marcelo, E-mail: savi@mecanica.ufrj.br [Universidade Federal do Rio de Janeiro, COPPE, Department of Mechanical Engineering, P.O. Box 68.503, 21.941.972 Rio de Janeiro, RJ (Brazil)
2011-08-15
Highlights: > A natural cardiac pacemaker is modeled by a modified Van der Pol oscillator. > Responses related to normal and chaotic, pathological functioning of the heart are investigated. > Chaos control methods are applied to avoid pathological behaviors of heart dynamics. > Different approaches are treated: stabilization of unstable periodic orbits and chaos suppression. - Abstract: The dynamics of cardiovascular rhythms have been widely studied due to the key aspects of the heart in the physiology of living beings. Cardiac rhythms can be either periodic or chaotic, being respectively related to normal and pathological physiological functioning. In this regard, chaos control methods may be useful to promote the stabilization of unstable periodic orbits using small perturbations. In this article, the extended time-delayed feedback control method is applied to a natural cardiac pacemaker described by a mathematical model. The model consists of a modified Van der Pol equation that reproduces the behavior of this pacemaker. Results show the ability of the chaos control strategy to control the system response performing either the stabilization of unstable periodic orbits or the suppression of chaotic response, avoiding behaviors associated with critical cardiac pathologies.
Chaos in a Bose-Einstein condensate
Institute of Scientific and Technical Information of China (English)
Wang Zhi-Xia; Ni Zheng-Guo; Cong Fu-Zhong; Liu Xue-Shen; Chen Lei
2010-01-01
It is demonstrated that Smale-horseshoe chaos exists in the time evolution of the one-dimensional Bose-Einstein condensate driven by time-periodic harmonic or inverted-harmonic potential.A formally exact solution of the timedependent Gross-Pitaevskii equation is constructed,which describes the matter shock waves with chaotic or periodic amplitudes and phases.
Chaos in a Bose—Einstein condensate
International Nuclear Information System (INIS)
It is demonstrated that Smale-horseshoe chaos exists in the time evolution of the one-dimensional Bose—Einstein condensate driven by time-periodic harmonic or inverted-harmonic potential. A formally exact solution of the time-dependent Gross—Pitaevskii equation is constructed, which describes the matter shock waves with chaotic or periodic amplitudes and phases
A Framework for Chaos Theory Career Counselling
Pryor, Robert G. L.
2010-01-01
Theory in career development counselling provides a map that counsellors can use to understand and structure the career counselling process. It also provides a means to communicate this understanding and structuring to their clients as part of the counselling intervention. The chaos theory of careers draws attention to the complexity,…
Chaos and fractals an elementary introduction
Feldman, David P
2012-01-01
For students with a background in elementary algebra, this text provides a vivid introduction to the key phenomena and ideas of chaos and fractals, including the butterfly effect, strange attractors, fractal dimensions, Julia sets and the Mandelbrot set, power laws, and cellular automata.
Spatio-temporal chaos : A solvable model
Diks, C; Takens, F; DeGoede, J
1997-01-01
A solvable coupled map lattice model exhibiting spatio-temporal chaos is studied. Exact expressions are obtained for the spectra of Lyapunov exponents as a function of the model parameters. Although the model has spatio-temporal structure, the time series measured at a single lattice site are shown
Many-body chaos at weak coupling
Stanford, Douglas
2016-10-01
The strength of chaos in large N quantum systems can be quantified using λ L , the rate of growth of certain out-of-time-order four point functions. We calculate λ L to leading order in a weakly coupled matrix Φ4 theory by numerically diagonalizing a ladder kernel. The computation reduces to an essentially classical problem.
Dynamic system uncertainty propagation using polynomial chaos
Institute of Scientific and Technical Information of China (English)
Xiong Fenfen; Chen Shishi; Xiong Ying
2014-01-01
The classic polynomial chaos method (PCM), characterized as an intrusive methodology, has been applied to uncertainty propagation (UP) in many dynamic systems. However, the intrusive polynomial chaos method (IPCM) requires tedious modification of the governing equations, which might introduce errors and can be impractical. Alternative to IPCM, the non-intrusive polynomial chaos method (NIPCM) that avoids such modifications has been developed. In spite of the frequent application to dynamic problems, almost all the existing works about NIPCM for dynamic UP fail to elaborate the implementation process in a straightforward way, which is important to readers who are unfamiliar with the mathematics of the polynomial chaos theory. Meanwhile, very few works have compared NIPCM to IPCM in terms of their merits and applicability. Therefore, the mathematic procedure of dynamic UP via both methods considering parametric and initial condition uncertainties are comparatively discussed and studied in the present paper. Comparison of accuracy and efficiency in statistic moment estimation is made by applying the two methods to several dynamic UP problems. The relative merits of both approaches are discussed and summarized. The detailed description and insights gained with the two methods through this work are expected to be helpful to engineering designers in solving dynamic UP problems.
CHAOS-BASED ADVANCED ENCRYPTION STANDARD
Abdulwahed, Naif B.
2013-05-01
This thesis introduces a new chaos-based Advanced Encryption Standard (AES). The AES is a well-known encryption algorithm that was standardized by U.S National Institute of Standard and Technology (NIST) in 2001. The thesis investigates and explores the behavior of the AES algorithm by replacing two of its original modules, namely the S-Box and the Key Schedule, with two other chaos- based modules. Three chaos systems are considered in designing the new modules which are Lorenz system with multiplication nonlinearity, Chen system with sign modules nonlinearity, and 1D multiscroll system with stair case nonlinearity. The three systems are evaluated on their sensitivity to initial conditions and as Pseudo Random Number Generators (PRNG) after applying a post-processing technique to their output then performing NIST SP. 800-22 statistical tests. The thesis presents a hardware implementation of dynamic S-Boxes for AES that are populated using the three chaos systems. Moreover, a full MATLAB package to analyze the chaos generated S-Boxes based on graphical analysis, Walsh-Hadamard spectrum analysis, and image encryption analysis is developed. Although these S-Boxes are dynamic, meaning they are regenerated whenever the encryption key is changed, the analysis results show that such S-Boxes exhibit good properties like the Strict Avalanche Criterion (SAC) and the nonlinearity and in the application of image encryption. Furthermore, the thesis presents a new Lorenz-chaos-based key expansion for the AES. Many researchers have pointed out that there are some defects in the original key expansion of AES and thus have motivated such chaos-based key expansion proposal. The new proposed key schedule is analyzed and assessed in terms of confusion and diffusion by performing the frequency and SAC test respectively. The obtained results show that the new proposed design is more secure than the original AES key schedule and other proposed designs in the literature. The proposed
Directory of Open Access Journals (Sweden)
Kostantinos Tziampasis
2015-03-01
Full Text Available Since Homer - who called the island ἑκατόμπολις (Iliad II, 649 - Crete is said to have had a hundred cities. In reality, even if the settlements were numerous, there weren’t more than 50-60 contemporary proper cities. Though most of their names have been saved through texts (either inscriptions or literature, not all have yet been located exactly. In fact, there has been an evolution of the political map of Crete. From around 55 cities in Classical times, the number of cities dropped to 27 in the Roman period and then to 22 in the Byzantine period. The paper will focus on Eastern Crete and study the establishment of the city-states and the evolution of their territory from the Archaic to the Roman period (which includes the study of the frontier, when it is possible. We will see that geography is a key element for understanding this evolution along with the archaeological and historical evidence that we have.
THEORY OF SECULAR CHAOS AND MERCURY'S ORBIT
International Nuclear Information System (INIS)
We study the chaotic orbital evolution of planetary systems, focusing on secular (i.e., orbit-averaged) interactions, which dominate on long timescales. We first focus on the evolution of a test particle that is forced by multiple planets. To linear order in eccentricity and inclination, its orbit precesses with constant frequencies. But nonlinearities modify the frequencies, and can shift them into and out of resonance with either the planets' eigenfrequencies (forming eccentricity or inclination secular resonances), or with linear combinations of those frequencies (forming mixed high-order secular resonances). The overlap of these nonlinear secular resonances drives secular chaos. We calculate the locations and widths of nonlinear secular resonances, display them together on a newly developed map (the 'map of the mean momenta'), and find good agreement between analytical and numerical results. This map also graphically demonstrates how chaos emerges from overlapping secular resonances. We then apply this newfound understanding to Mercury to elucidate the origin of its orbital chaos. We find that since Mercury's two free precession frequencies (in eccentricity and inclination) lie within ∼25% of two other eigenfrequencies in the solar system (those of the Jupiter-dominated eccentricity mode and the Venus-dominated inclination mode), secular resonances involving these four modes overlap and cause Mercury's chaos. We confirm this with N-body integrations by showing that a slew of these resonant angles alternately librate and circulate. Our new analytical understanding allows us to calculate the criterion for Mercury to become chaotic: Jupiter and Venus must have eccentricity and inclination of a few percent. The timescale for Mercury's chaotic diffusion depends sensitively on the forcing. As it is, Mercury appears to be perched on the threshold for chaos, with an instability timescale comparable to the lifetime of the solar system.
Controlling halo-chaos via wavelet-based feedback
Directory of Open Access Journals (Sweden)
Jin-Qing Fang
2002-01-01
Full Text Available Halo-chaos in high-current accelerator has become one of the key issues because it can cause excessive radioactivity from the accelerators and significantly limits the applications of the new accelerators in industrial and other fields. Some general engineering methods for chaos control have been developed, but they generally are unsuccessful for halo-chaos suppression due to many technical constraints. In this article, controllability condition for beam halo-chaos is analyzed qualitatively. Then Particles-in-Cell (PIC simulations explore the nature of beam halo-chaos formation. A nonlinear control method and wavelet function feedback controller are proposed for controlling beam halo-chaos. After control of beam halo-chaos for initial proton beam with water bag distributions, the beam halo strength factor H is reduced to zero, and other statistical physical quantities of beam halo-chaos are doubly reduced. The results show that the developed methods in this paper are very effective for proton beam halo-chaos suppression. Potential application of the halo-chaos control method is finally pointed out.
Proceedings of the 2nd Experimental Chaos Conference
Ditto, William; Pecora, Lou; Shlesinger, Michael; Spano, Mark; Vohra, Sandeep
1995-02-01
The Table of Contents for the full book PDF is as follows: * Introduction * Spatiotemporal Phenomena * Experimental Studies of Chaotic Mixing * Using Random Maps in the Analysis of Experimental Fluid Flows * Transition to Spatiotemporal Chaos in a Reaction-Diffusion System * Ion-Dynamical Chaos in Plasmas * Optics * Chaos in a Synchronously Driven Optical Resonator * Chaos, Patterns and Defects in Stimulated Scattering Phenomena * Test of the Normal Form for a Subcritical Bifurcation * Observation of Bifurcations and Chaos in a Driven Fiber Optic Coil * Applications -- Communications * Robustness and Signal Recovery in a Synchronized Chaotic System * Synchronizing Nonautonomous Chaotic Circuits * Synchronization of Pulse-Coupled Chaotic Oscillators * Ocean Transmission Effects on Chaotic Signals * Controlling Symbolic Dynamics for Communication * Applications -- Control * Analysis of Nonlinear Actuators Using Chaotic Waveforms * Controlling Chaos in a Quasiperiodic Electronic System * Control of Chaos in a CO2 Laser * General Research * Video-Based Analysis of Bifurcation Phenomena in Radio-Frequency-Excited Inert Gas Plasmas * Transition from Soliton to Chaotic Motion During the Impact of a Nonlinear Structure * Sonoluminescence in a Single Bubble: Periodic, Quasiperiodic and Chaotic Light Source * Quantum Chaos Experiments Using Microwave Cavities * Experiments on Quantum Chaos With and Without Time Reversibility * When Small Noise Imposed on Deterministic Dynamics Becomes Important * Biology * Chaos Control for Cardiac Arrhythmias * Irregularities in Spike Trains of Cat Retinal Ganglion Cells * Broad-Band Synchronization in Monkey Neocortex * Applicability of Correlation Dimension Calculations to Blood Pressure Signal in Rats * Tests for Deterministic Chaos in Noisy Time Series * The Crayfish Mechanoreceptor Cell: A Biological Example of Stochastic Resonance * Chemistry * Chaos During Heterogeneous Chemical Reactions * Stabilizing and Tracking Unstable Periodic
Intrinsic Time Quantum Gravity
Yu, Hoi Lai
2016-01-01
Correct identification of the true gauge symmetry of General Relativity being 3d spatial diffeomorphism invariant(3dDI) (not the conventional infinite tensor product group with principle fibre bundle structure), together with intrinsic time extracted from clean decomposition of the canonical structure yields a self-consistent theory of quantum gravity. A new set of fundamental commutation relations is also presented. The basic variables are the eight components of the unimodular part of the s...
Optomechanically induced stochastic resonance and chaos transfer between optical fields
Monifi, Faraz; Zhang, Jing; Özdemir, Şahin Kaya; Peng, Bo; Liu, Yu-Xi; Bo, Fang; Nori, Franco; Yang, Lan
2016-06-01
Chaotic dynamics has been reported in many physical systems and has affected almost every field of science. Chaos involves hypersensitivity to the initial conditions of a system and introduces unpredictability into its output. Thus, it is often unwanted. Interestingly, the very same features make chaos a powerful tool to suppress decoherence, achieve secure communication and replace background noise in stochastic resonance—a counterintuitive concept that a system's ability to transfer information can be coherently amplified by adding noise. Here, we report the first demonstration of chaos-induced stochastic resonance in an optomechanical system, as well as the optomechanically mediated chaos transfer between two optical fields such that they follow the same route to chaos. These results will contribute to the understanding of nonlinear phenomena and chaos in optomechanical systems, and may find applications in the chaotic transfer of information and for improving the detection of otherwise undetectable signals in optomechanical systems.
Chaos in electric drive systems analysis control and application
Chau, K T
2011-01-01
In Chaos in Electric Drive Systems: Analysis, Control and Application authors Chau and Wang systematically introduce an emerging technology of electrical engineering that bridges abstract chaos theory and practical electric drives. The authors consolidate all important information in this interdisciplinary technology, including the fundamental concepts, mathematical modeling, theoretical analysis, computer simulation, and hardware implementation. The book provides comprehensive coverage of chaos in electric drive systems with three main parts: analysis, control and application. Corresponding drive systems range from the simplest to the latest types: DC, induction, synchronous reluctance, switched reluctance, and permanent magnet brushless drives.The first book to comprehensively treat chaos in electric drive systemsReviews chaos in various electrical engineering technologies and drive systemsPresents innovative approaches to stabilize and stimulate chaos in typical drivesDiscusses practical application of cha...
CONGENITAL HIGH AIRWAY OBSTRUCTION (CHAOS SYNDROME: A RARE CASE PRESENTATION
Directory of Open Access Journals (Sweden)
Dinakara
2014-04-01
Full Text Available Congenital high airway obstruction syndrome (CHAOS results in a predictable constellation of findings: large echogenic lungs flattened or inverted diaphragms, dilated airways distal to the obstruction, and fetal ascites and/or hydrops.1 The finding of CHAOS on prenatal ultrasound examination is diagnostic of complete or near-complete obstruction of the fetal upper airway, most likely caused by laryngeal atresia. A greater understanding of the natural history of CHAOS may permit improved prenatal and perinatal management
Comments on microcausality, chaos, and gravitational observables
Marolf, Donald
2015-12-01
Observables in gravitational systems must be non-local so as to be invariant under diffeomorphism gauge transformations. But at the classical level some such observables can nevertheless satisfy an exact form of microcausality. This property is conjectured to remain true at all orders in the semiclassical expansion, though with limitations at finite ℏ or {{\\ell }}{Planck}. We also discuss related issues concerning observables in black hole spacetimes and comment on the senses in which they do and do not experience the form of chaos identified by Shenker and Stanford. In particular, in contrast to the situation in a reflecting cavity, this chaos does not afflict observables naturally associated with Hawking radiation for evaporating black holes.
Comments on Microcausality, Chaos, and Gravitational Observables
Marolf, Donald
2015-01-01
Observables in gravitational systems must be non-local so as to be invariant under diffeomorphism gauge transformations. But at the classical level some such observables can nevertheless satisfy an exact form of microcausality. This property is conjectured to remain true at all orders in the semiclassical expansion, though with limitations at finite $\\hbar$ or $\\ell_{Planck}$. We also discuss related issues concerning observables in black hole spacetimes and comment on the senses in which they do and do not experience the form of chaos identified by Shenker and Stanford. In particular, in contrast to the situation in a reflecting cavity, this chaos does not afflict observables naturally associated with Hawking radiation for evaporating black holes.
Buoyancy driven turbulence and distributed chaos
Bershadskii, A
2016-01-01
It is shown, using results of recent direct numerical simulations, laboratory experiments and atmospheric measurements, that buoyancy driven turbulence exhibits a broad diversity of the types of distributed chaos with its stretched exponential spectrum $\\exp(-k/k_{\\beta})^{\\beta}$. The distributed chaos with $\\beta = 1/3$ (determined by the helicity correlation integral) is the most common feature of the stably stratified turbulence (due to the strong helical waves presence). These waves mostly dominate spectral properties of the vertical component of velocity field, while the horizontal component is dominated by the diffusive processes both for the weak and strong stable stratification ($\\beta =2/3$). For the last case influence of the low boundary can overcome the wave effects and result in $\\beta =1/2$ for the vertical component of the velocity field (the spontaneous breaking of the space translational symmetry - homogeneity). For the unstably stratified turbulence in the Rayleigh-Taylor mixing zone the di...
The CHAOS-4 Geomagnetic Field Model
DEFF Research Database (Denmark)
Olsen, Nils; Finlay, Chris; Lühr, H.;
We present CHAOS-4, a new version in the CHAOS model series, which aims at describing the Earth's magnetic field with high spatial resolution (terms up to spherical degree n=90 for the crustal field, and up to n=16 for the time-varying core field are robustly determined) and high temporal...... resolution (allowing for investigations of sub-annual core field changes). More than 14 years of data from the satellites Ørsted (March 1999 to June 2013), CHAMP (July 2000 to September 2010) and SAC-C (2000 to 2004), augmented with ground observatory revised monthly mean values (1997 to 2013) have been used...... for this model. Maximum spherical harmonic degree of the static (crustal) field is n=100. The core field time changes are expressed by spherical harmonic expansion coefficients up to n=20, described by order 6 splines (with 6-month knot spacing) spanning the time interval 1997.0 to 2013.5. The third time...
Chaos in hydrodynamic BL Herculis models
Smolec, R
2014-01-01
We present non-linear, convective, BL Her-type hydrodynamic models that show complex variability characteristic for deterministic chaos. The bifurcation diagram reveals a rich structure, with many phenomena detected for the first time in hydrodynamic models of pulsating stars. The phenomena include not only period doubling cascades en route to chaos (detected in earlier studies) but also periodic windows within chaotic band, type-I and type-III intermittent behaviour, interior crisis bifurcation and others. Such phenomena are known in many textbook chaotic systems, from the simplest discrete logistic map, to more complex systems like Lorenz equations. We discuss the physical relevance of our models. Although except of period doubling such phenomena were not detected in any BL Her star, chaotic variability was claimed in several higher luminosity siblings of BL Her stars - RV Tau variables, and also in longer-period, luminous irregular pulsators. Our models may help to understand these poorly studied stars. Pa...
Chaos synchronization in networks of semiconductor superlattices
Li, Wen; Aviad, Yaara; Reidler, Igor; Song, Helun; Huang, Yuyang; Biermann, Klaus; Rosenbluh, Michael; Zhang, Yaohui; Grahn, Holger T.; Kanter, Ido
2015-11-01
Chaos synchronization has been demonstrated as a useful building block for various tasks in secure communications, including a source of all-electronic ultrafast physical random number generators based on room temperature spontaneous chaotic oscillations in a DC-biased weakly coupled GaAs/Al0.45Ga0.55As semiconductor superlattice (SSL). Here, we experimentally demonstrate the emergence of several types of chaos synchronization, e.g. leader-laggard, face-to-face and zero-lag synchronization in network motifs of coupled SSLs consisting of unidirectional and mutual coupling as well as self-feedback coupling. Each type of synchronization clearly reflects the symmetry of the topology of its network motif. The emergence of a chaotic SSL without external feedback and synchronization among different structured SSLs open up the possibility for advanced secure multi-user communication methods based on large networks of coupled SSLs.
Chaos in a Hydraulic Control Valve
Hayashi, S.; Hayase, T.; Kurahashi, T.
1997-08-01
In this paper we have studied the instability and chaos occurring in a pilot-type poppet valve circuit. The system consists of a poppet valve, an upstream plenum chamber, a supply pipeline and an orifice inserted between the pelnum and the pipeline. Although the poppet valve rests on the seat stably for a supply pressure lower than the cracking pressure, the circuit becomes unstable for an initial disturbance beyond a critical value and develops a self-excited vibration. In this unstable region, chaotic vibration appears at the period-doubling bifurcation. We have investigated the stability of the circuit and the chaotic phenomenon numerically, and elucidated it by power spectra, a bifurcation diagram and Lyapunov exponent calculations, showing that the phenomenon follows the Feigenbaum route to chaos.Copyright 1997 Academic Press Limited
Quantum chaos in QCD and hadrons
Markum, H; Pullirsch, R; Sengl, B; Wagenbrunn, R F; Markum, Harald; Plessas, Willibald; Pullirsch, Rainer; Sengl, Bianka; Wagenbrunn, Robert F.
2005-01-01
This article is the written version of a talk delivered at the Workshop on Nonlinear Dynamics and Fundamental Interactions in Tashkent and starts with an introduction into quantum chaos and its relationship to classical chaos. The Bohigas-Giannoni-Schmit conjecture is formulated and evaluated within random-matrix theory. In accordance to the title, the presentation is twofold and begins with research results on quantum chromodynamics and the quark-gluon plasma. We conclude with recent research work on the spectroscopy of baryons. Within the framework of a relativistic constituent quark model we investigate the excitation spectra of the nucleon and the delta with regard to a possible chaotic behavior for the cases when a hyperfine interaction of either Goldstone-boson-exchange or one-gluon-exchange type is added to the confinement interaction. Agreement with predictions from the experimental hadron spectrum is established.
Chaos theory perspective for industry clusters development
Yu, Haiying; Jiang, Minghui; Li, Chengzhang
2016-03-01
Industry clusters have outperformed in economic development in most developing countries. The contributions of industrial clusters have been recognized as promotion of regional business and the alleviation of economic and social costs. It is no doubt globalization is rendering clusters in accelerating the competitiveness of economic activities. In accordance, many ideas and concepts involve in illustrating evolution tendency, stimulating the clusters development, meanwhile, avoiding industrial clusters recession. The term chaos theory is introduced to explain inherent relationship of features within industry clusters. A preferred life cycle approach is proposed for industrial cluster recessive theory analysis. Lyapunov exponents and Wolf model are presented for chaotic identification and examination. A case study of Tianjin, China has verified the model effectiveness. The investigations indicate that the approaches outperform in explaining chaos properties in industrial clusters, which demonstrates industrial clusters evolution, solves empirical issues and generates corresponding strategies.
Experimental Study of the Sampled Labyrinth Chaos
Directory of Open Access Journals (Sweden)
J. Petrzela
2011-12-01
Full Text Available In this paper, some new numerical as well as experimental results connected with the so-called labyrinth chaos are presented. This very unusual chaotic motion can be generated by mathematical model involving the scalar goniometrical functions which makes a three-dimensional autonomous dynamical system strongly nonlinear. Final circuitry implementation with analog core and digital parts can be used for modeling Brownian motion. From the viewpoint of generating chaotic motion by some electronic circuit, first step is to solve problems associated with the two-port nonlinear transfer functions synthesis. In the case of labyrinth chaos the finite dynamical range of the input variables introduced by the used active elements usually limits the performance greatly, similarly as it holds for the multi-grid spiral attractors. This paper shows an elegant way how to remove these obstacles by using uni-versal multiple-port with internal digital signal processing.
Lesecque, Yann; Glémin, Sylvain; Lartillot, Nicolas; Mouchiroud, Dominique; Duret, Laurent
2014-11-01
Recombination is an essential process in eukaryotes, which increases diversity by disrupting genetic linkage between loci and ensures the proper segregation of chromosomes during meiosis. In the human genome, recombination events are clustered in hotspots, whose location is determined by the PRDM9 protein. There is evidence that the location of hotspots evolves rapidly, as a consequence of changes in PRDM9 DNA-binding domain. However, the reasons for these changes and the rate at which they occur are not known. In this study, we investigated the evolution of human hotspot loci and of PRDM9 target motifs, both in modern and archaic human lineages (Denisovan) to quantify the dynamic of hotspot turnover during the recent period of human evolution. We show that present-day human hotspots are young: they have been active only during the last 10% of the time since the divergence from chimpanzee, starting to be operating shortly before the split between Denisovans and modern humans. Surprisingly, however, our analyses indicate that Denisovan recombination hotspots did not overlap with modern human ones, despite sharing similar PRDM9 target motifs. We further show that high-affinity PRDM9 target motifs are subject to a strong self-destructive drive, known as biased gene conversion (BGC), which should lead to the loss of the majority of them in the next 3 MYR. This depletion of PRDM9 genomic targets is expected to decrease fitness, and thereby to favor new PRDM9 alleles binding different motifs. Our refined estimates of the age and life expectancy of human hotspots provide empirical evidence in support of the Red Queen hypothesis of recombination hotspots evolution. PMID:25393762
Directory of Open Access Journals (Sweden)
Yann Lesecque
2014-11-01
Full Text Available Recombination is an essential process in eukaryotes, which increases diversity by disrupting genetic linkage between loci and ensures the proper segregation of chromosomes during meiosis. In the human genome, recombination events are clustered in hotspots, whose location is determined by the PRDM9 protein. There is evidence that the location of hotspots evolves rapidly, as a consequence of changes in PRDM9 DNA-binding domain. However, the reasons for these changes and the rate at which they occur are not known. In this study, we investigated the evolution of human hotspot loci and of PRDM9 target motifs, both in modern and archaic human lineages (Denisovan to quantify the dynamic of hotspot turnover during the recent period of human evolution. We show that present-day human hotspots are young: they have been active only during the last 10% of the time since the divergence from chimpanzee, starting to be operating shortly before the split between Denisovans and modern humans. Surprisingly, however, our analyses indicate that Denisovan recombination hotspots did not overlap with modern human ones, despite sharing similar PRDM9 target motifs. We further show that high-affinity PRDM9 target motifs are subject to a strong self-destructive drive, known as biased gene conversion (BGC, which should lead to the loss of the majority of them in the next 3 MYR. This depletion of PRDM9 genomic targets is expected to decrease fitness, and thereby to favor new PRDM9 alleles binding different motifs. Our refined estimates of the age and life expectancy of human hotspots provide empirical evidence in support of the Red Queen hypothesis of recombination hotspots evolution.
DEFF Research Database (Denmark)
Klösgen, Beate; Bruun, Sara; Hansen, Søren;
with an AFM (2). The intuitive explanation for the depletion based on "hydrophobic mismatch" between the obviously hydrophilic bulk phase of water next to the hydrophobic polymer. It would thus be an intrinsic property of all interfaces between non-matching materials. The detailed physical interaction path...... The presence of a depletion layer of water along extended hydrophobic interfaces, and a possibly related formation of nanobubbles, is an ongoing discussion. The phenomenon was initially reported when we, years ago, chose thick films (~300-400Å) of polystyrene as cushions between a crystalline...
DEFF Research Database (Denmark)
Klösgen, Beate; Bruun, Sara; Hansen, Søren;
with an AFM (2). The intuitive explanation for the depletion based on "hydrophobic mismatch" between the obviously hydrophilic bulk phase of water next to the hydrophobic polymer. It would thus be an intrinsic property of all interfaces between non-matching materials. The detailed physical interaction path...... The presence of a depletion layer of water along extended hydrophobic interfaces, and a possibly related formation of nanobubbles, is an ongoing discussion. The phenomenon was initially reported when we, years ago, chose thick films (~300-400Å) of polystyrene as cushions between a crystalline...
Frozen spatial chaos induced by boundaries
Eguiluz, V M; Piro, O; Balle, S; Eguiluz, Victor M.; Hernandez-Garcia, Emilio; Piro, Oreste; Balle, Salvador
1999-01-01
We show that rather simple but non-trivial boundary conditions could induce the appearance of spatial chaos (that is stationary, stable, but spatially disordered configurations) in extended dynamical systems with very simple dynamics. We exemplify the phenomenon with a nonlinear reaction-diffusion equation in a two-dimensional undulated domain. Concepts from the theory of dynamical systems, and a transverse-single-mode approximation are used to describe the spatially chaotic structures.
Delayed Self-Synchronization in Homoclinic Chaos
Arecchi, F. T.; Meucci, R.; E. Allaria; Di Garbo, A.; Tsimring, L. S.
2001-01-01
The chaotic spike train of a homoclinic dynamical system is self-synchronized by re-inserting a small fraction of the delayed output. Due to the sensitive nature of the homoclinic chaos to external perturbations, stabilization of very long periodic orbits is possible. On these orbits, the dynamics appears chaotic over a finite time, but then it repeats with a recurrence time that is slightly longer than the delay time. The effect, called delayed self-synchronization (DSS), displays analogies ...
Gravity Waves, Chaos, and Spinning Compact Binaries
Levin, Janna
1999-01-01
Spinning compact binaries are shown to be chaotic in the Post-Newtonian expansion of the two body system. Chaos by definition is the extreme sensitivity to initial conditions and a consequent inability to predict the outcome of the evolution. As a result, the spinning pair will have unpredictable gravitational waveforms during coalescence. This poses a challenge to future gravity wave observatories which rely on a match between the data and a theoretical template.
Legal System and Legal Chaos Theory
Amir Syarifudin; Indah Febriani
2015-01-01
Order of the universe and other objects can be described either by cosmology and physics. But from of the regularity of the object there in terms or aspect of irregularity or fractal (broken) that difficult to describe by Auklides and Calculus mathematical models. Benoit Medelbrot tried to explain the chaotic objects with fractal theory which basically a branch of mathematics. The fractal theory affect the view of the law that inspired Charles Sampford which then sparked a legal chaos theory....
Classical and Quantum Chaos in Atom Optics
Saif, Farhan
2006-01-01
The interaction of an atom with an electromagnetic field is discussed in the presence of a time periodic external modulating force. It is explained that a control on atom by electromagnetic fields helps to design the quantum analog of classical optical systems. In these atom optical systems chaos may appear at the onset of external fields. The classical and quantum chaotic dynamics is discussed, in particular in an atom optics Fermi accelerator. It is found that the quantum dynamics exhibits ...
Complex motions and chaos in nonlinear systems
Machado, José; Zhang, Jiazhong
2016-01-01
This book brings together 10 chapters on a new stream of research examining complex phenomena in nonlinear systems—including engineering, physics, and social science. Complex Motions and Chaos in Nonlinear Systems provides readers a particular vantage of the nature and nonlinear phenomena in nonlinear dynamics that can develop the corresponding mathematical theory and apply nonlinear design to practical engineering as well as the study of other complex phenomena including those investigated within social science.
Quantum chaos in small quantum networks
Kim, I; Kim, Ilki; Mahler, Guenter
1999-01-01
We study a 2-spin quantum Turing architecture, in which discrete local rotations \\alpha_m of the Turing head spin alternate with quantum controlled NOT-operations. We show that a single chaotic parameter input \\alpha_m leads to a chaotic dynamics in the entire Hilbert space. The instability of periodic orbits on the Turing head and `chaos swapping' onto the Turing tape are demonstrated explicitly as well as exponential parameter sensitivity of the Bures metric.
Chaos in a topologically transitive system
Institute of Scientific and Technical Information of China (English)
XIONG; Jincheng
2005-01-01
The chaotic phenomena have been studied in a topologically transitive system and it has been shown that the erratic time dependence of orbits in such a topologically transitive system is more complicated than what described by the well-known technology "Li-Yorke chaos". The concept "sensitive dependency on initial conditions" has been generalized, and the chaotic phenomena has been discussed for transitive systems with the generalized sensitive dependency property.
Reducing or enhancing chaos using periodic orbits.
Bachelard, R; Chandre, C; Leoncini, X
2006-06-01
A method to reduce or enhance chaos in Hamiltonian flows with two degrees of freedom is discussed. This method is based on finding a suitable perturbation of the system such that the stability of a set of periodic orbits changes (local bifurcations). Depending on the values of the residues, reflecting their linear stability properties, a set of invariant tori is destroyed or created in the neighborhood of the chosen periodic orbits. An application on a paradigmatic system, a forced pendulum, illustrates the method.
Chaos in free electron laser oscillators
Energy Technology Data Exchange (ETDEWEB)
Bruni, C. [Univ Paris 11, LAL, UMR 8607, F-91898 Orsay, (France); Bachelard, R.; Couprie, M.E. [Synchrotron SOLEIL, F-91192 Gif Sur Yvette, (France); Garzella, D. [CEA DSM DRECAM SPAM, F-91191 Gif Sur Yvette, (France); Orlandi, G.L. [CR Frascati FIM FISACC, ENEA, I-00044 Frascati, (Italy)
2009-07-01
The chaotic nature of a storage-ring free electron laser (FEL) is investigated. The derivation of a low embedding dimension for the dynamics allows the low-dimensionality of this complex system to be observed, whereas its unpredictability is demonstrated, in some ranges of parameters, by a positive Lyapounov exponent. The route to chaos is then explored by tuning a single control parameter, and a period-doubling cascade is evidenced, as well as intermittence. (authors)
Nonlinear Dynamics In Quantum Physics -- Quantum Chaos and Quantum Instantons
Kröger, H.
2003-01-01
We discuss the recently proposed quantum action - its interpretation, its motivation, its mathematical properties and its use in physics: quantum mechanical tunneling, quantum instantons and quantum chaos.
Bifurcations and Chaos in Duffing Equation
Institute of Scientific and Technical Information of China (English)
2007-01-01
The Duffing equation with even-odd asymmetrical nonlinear-restoring force and one external forcing is investigated. The conditions of existence of primary resonance, second-order, third-order subharmonics, m-order subharmonics and chaos are given by using the second-averaging method, the Melnikov method and bifurcation theory. Numerical simulations including bifurcation diagram, bifurcation surfaces and phase portraits show the consistence with the theoretical analysis. The numerical results also exhibit new dynamical behaviors including onset of chaos, chaos suddenly disappearing to periodic orbit, cascades of inverse period-doubling bifurcations, period-doubling bifurcation, symmetry period-doubling bifurcations of period-3 orbit, symmetry-breaking of periodic orbits, interleaving occurrence of chaotic behaviors and period-one orbit, a great abundance of periodic windows in transient chaotic regions with interior crises and boundary crisis and varied chaotic attractors. Our results show that many dynamical behaviors are strictly departure from the behaviors of the Duffing equation with odd-nonlinear restoring force.
Dynamics and chaos control of gyrostat satellite
International Nuclear Information System (INIS)
Highlights: ► Free dual-spin gyrostat with a small rotor asymmetry is considered. ► Equations in Andoyer-Deprit canonical dimensionless variables are obtained. ► Phase space heteroclinic and homoclinic trajectories are written in closed form. ► Modified Melnikov function is used to construct the control that eliminates chaos. - Abstract: We consider the chaotic motion of the free gyrostat consisting of a platform with a triaxial inertia ellipsoid and a rotor with a small asymmetry with respect to the axis of rotation. Dimensionless equations of motion of the system with perturbations caused by small asymmetries of the rotor are written in Andoyer-Deprit variables. These perturbations lead to separatrix chaos. For gyrostats with different ratios of moments of inertia heteroclinic and homoclinic trajectories are written in closed-form. These trajectories are used for constructing modified Melnikov function, which is used for determine the control that eliminates separatrix chaos. Melnikov function and phase space trajectory are built to show the effectiveness of the control.
The chaos and order in nuclear molecular dynamics; Chaos i porzadek w jadrowej dynamice molekularnej
Energy Technology Data Exchange (ETDEWEB)
Srokowski, T. [Institute of Nuclear Physics, Cracow (Poland)
1995-12-31
The subject of the presented report is role of chaos in scattering processes in the frame of molecular dynamics. In this model, it is assumed that scattering particles (nuclei) consist of not-interacted components as alpha particles or {sup 12}C, {sup 16}O and {sup 20}Ne clusters. The results show such effects as dynamical in stabilities and fractal structure as well as compound nuclei decay and heavy-ion fusion. The goal of the report is to make the reader more familiar with the chaos model and its application to nuclear phenomena. 157 refs, 40 figs.
Application of Chaos Theory to Psychological Models
Blackerby, Rae Fortunato
This dissertation shows that an alternative theoretical approach from physics--chaos theory--offers a viable basis for improved understanding of human beings and their behavior. Chaos theory provides achievable frameworks for potential identification, assessment, and adjustment of human behavior patterns. Most current psychological models fail to address the metaphysical conditions inherent in the human system, thus bringing deep errors to psychological practice and empirical research. Freudian, Jungian and behavioristic perspectives are inadequate psychological models because they assume, either implicitly or explicitly, that the human psychological system is a closed, linear system. On the other hand, Adlerian models that require open systems are likely to be empirically tenable. Logically, models will hold only if the model's assumptions hold. The innovative application of chaotic dynamics to psychological behavior is a promising theoretical development because the application asserts that human systems are open, nonlinear and self-organizing. Chaotic dynamics use nonlinear mathematical relationships among factors that influence human systems. This dissertation explores these mathematical relationships in the context of a sample model of moral behavior using simulated data. Mathematical equations with nonlinear feedback loops describe chaotic systems. Feedback loops govern the equations' value in subsequent calculation iterations. For example, changes in moral behavior are affected by an individual's own self-centeredness, family and community influences, and previous moral behavior choices that feed back to influence future choices. When applying these factors to the chaos equations, the model behaves like other chaotic systems. For example, changes in moral behavior fluctuate in regular patterns, as determined by the values of the individual, family and community factors. In some cases, these fluctuations converge to one value; in other cases, they diverge in
Using largest Lyapunov exponent to confirm the intrinsic stability of boiling water reactors
Energy Technology Data Exchange (ETDEWEB)
Gavilian-Moreno, Carlos [Iberdrola Generacion, S.A., Cofrentes Nuclear Power Plant, Project Engineering Department, Paraje le Plano S/N, Valencia (Spain); Espinosa-Paredes, Gilberto [Area de ingeniera en Recursos Energeticos, Universidad Autonoma Metropolitana-Iztapalapa, Mexico city (Mexico)
2016-04-15
The aim of this paper is the study of instability state of boiling water reactors with a method based in largest Lyapunov exponents (LLEs). Detecting the presence of chaos in a dynamical system is an important problem that is solved by measuring the LLE. Lyapunov exponents quantify the exponential divergence of initially close state-space trajectories and estimate the amount of chaos in a system. This method was applied to a set of signals from several nuclear power plant (NPP) reactors under commercial operating conditions that experienced instabilities events, apparently each of a different nature. Laguna Verde and Forsmark NPPs with in-phase instabilities, and Cofrentes NPP with out-of-phases instability. This study presents the results of intrinsic instability in the boiling water reactors of three NPPs. In the analyzed cases the limit cycle was not reached, which implies that the point of equilibrium exerts influence and attraction on system evolution.
Intrinsic anion oxidation potentials.
Johansson, Patrik
2006-11-01
Anions of lithium battery salts have been investigated by electronic structure calculations with the objective to find a computational measure to correlate with the observed (in)stability of nonaqueous lithium battery electrolytes vs oxidation often encountered in practice. Accurate prediction of intrinsic anion oxidation potentials is here made possible by computing the vertical free energy difference between anion and neutral radical (Delta Gv) and further strengthened by an empirical correction using only the anion volume as a parameter. The 6-311+G(2df,p) basis set, the VSXC functional, and the C-PCM SCRF algorithm were used. The Delta Gv calculations can be performed using any standard computational chemistry software. PMID:17078600
Intrinsic Time Quantum Gravity
Yu, Hoi Lai
2016-01-01
Correct identification of the true gauge symmetry of General Relativity being 3d spatial diffeomorphism invariant(3dDI) (not the conventional infinite tensor product group with principle fibre bundle structure), together with intrinsic time extracted from clean decomposition of the canonical structure yields a self-consistent theory of quantum gravity. A new set of fundamental commutation relations is also presented. The basic variables are the eight components of the unimodular part of the spatial dreibein and eight SU(3) generators which correspond to Klauder's momentric variables that characterize a free theory of quantum gravity. The commutation relations are not canonical, but have well defined group theoretical meanings. All fundamental entities are dimensionless; and the quantum wave functionals are preferentially in the dreibein representation. The successful quantum theory of gravity involves only broad spectrum of knowledge and deep insights but no exotic idea.
Major open problems in chaos theory and nonlinear dynamics
Li, Y Charles
2013-01-01
Nowadays, chaos theory and nonlinear dynamics lack research focuses. Here we mention a few major open problems: 1. an effective description of chaos and turbulence, 2. rough dependence on initial data, 3. arrow of time, 4. the paradox of enrichment, 5. the paradox of pesticides, 6. the paradox of plankton.
Stratified Spatiotemporal Chaos in Anisotropic Reaction-Diffusion Systems
Energy Technology Data Exchange (ETDEWEB)
Baer, M.; Thiele, U. [Max-Planck-Institut fuer Physik Komplexer Systeme, Noethnitzer Strasse 38, 01187 Dresden (Germany); Hagberg, A. [Theoretical Division and Center for Nonlinear Studies, Los Alamos National Laboratory, Los Alamos, New Mexico 87545 (United States); Baer, M.; Meron, E. [The Jacob Blaustein Institute for Desert Research and the Physics Department, Ben-Gurion University, Sede Boker Campus 84990 (Israel); Thiele, U. [Instituto Pluridisciplinar, Universidad Complutense Madrid, Paseo Juan XXIII 1, E-28040 Madrid (Spain)
1999-09-01
Numerical simulations of two-dimensional pattern formation in an anisotropic bistable reaction-diffusion medium reveal a new dynamical state, stratified spatiotemporal chaos, characterized by strong correlations along one of the principal axes. Equations that describe the dependence of front motion on the angle illustrate the mechanism leading to stratified chaos. {copyright} {ital 1999} {ital The American Physical Society}
Controlling Beam Halo-Chaos via Time-Delayed Feedback
Institute of Scientific and Technical Information of China (English)
FANG Jin-Qing; WENG Jia-Qiang; ZHU Lun-Wu; LUO Xiao-Shu
2004-01-01
The study of controlling high-current proton beam halo-chaos has become a key concerned issue for many important applications. In this paper, time-delayed feedback control method is proposed for beam halo-chaos. Particle in cell simulation results show that the method is very effective and has some advantages for high-current beam experiments and engineering.
Toward a definition of chaos for general relativity
Witt, Donald; Schleich, Kristin
1996-01-01
General relativity exhibits a unique feature not represented in standard examples of chaotic systems; it is a spacetime diffeomorphism invariant theory. Thus many characterizations of chaos do not work. It is therefore necessary to develop a definition of chaos suitable for application to general relativity. This presentation will present results towards this goal.
Using a quantum computer to investigate quantum chaos
Schack, Ruediger
1997-01-01
We show that the quantum baker's map, a prototypical map invented for theoretical studies of quantum chaos, has a very simple realization in terms of quantum gates. Chaos in the quantum baker's map could be investigated experimentally on a quantum computer based on only 3 qubits.
The Chaos Game on a General Iterated Function System
Barnsley, Michael
2010-01-01
The main theorem of this paper establishes conditions under which the "chaos game" algorithm almost surely yields the attractor of an iterated function system. The theorem holds in a very general setting, even for non contractive iterated function systems, and under weaker conditions on the random orbit of the chaos game than obtained previously.
Research on a family of n-scroll chaos generators
International Nuclear Information System (INIS)
This paper studies a family of n-scroll chaos generators using a modified Chua's circuit. A mathematic model of the generators is established, the relationship between equilibrium points and scrolls is also analyzed, and a general theorem for generation of n-scroll chaos attractors is given. Numerical simulation is illustrated, showing excellent agreement with our theoretical predictions
The "Chaos" Pattern in Piaget's Theory of Cognitive Development.
Lindsay, Jean S.
Piaget's theory of the cognitive development of the child is related to the recently developed non-linear "chaos" model. The term "chaos" refers to the tendency of dynamical, non-linear systems toward irregular, sometimes unpredictable, deterministic behavior. Piaget identified this same pattern in his model of cognitive development in children.…
Nonlinear Resonance Leading to Beam Halo-chaos-complexity
Institute of Scientific and Technical Information of China (English)
2002-01-01
In this paper,nonlinear resonances of the particle-core taken placed in a space-charge dominatedbeam are suited. Overlapping resonance leads to chaos and halo formation. That is one of most importantphysical mechanisms. Duo to beam halo-chaos is essentially a spatiotemporal chaotic motion, Such beam
Master Teachers: Making a Difference on the Edge of Chaos
Chapin, Dexter
2008-01-01
The No Child Left Behind legislation, by legitimizing a stark, one-size-fits-all, industrial model of education, has denied the inherent complexity and richness of what teachers do. Discussing teaching in terms of Chaos Theory, Chapin explains that while excellent teaching may occur at the edge of chaos, it is not chaotic. There are patterns…
Torus Destruction and Chaos-Chaos Intermittency in a Commodity Distribution Chain
DEFF Research Database (Denmark)
Sosnovtseva, O.; Mosekilde, Erik
1997-01-01
The destruction of two-dimensional tori T2 and the transitions to chaos are studied in a high-dimensional model describing the decision-making behavior of human subjects in a simulated managerial environment (the beer production-distribution model). Two different routes from quasiperiodicity...
Dynamical chaos in chip-scale optomechanical oscillators
Wu, Jiagui; Huang, Yongjun; Zhou, Hao; Yang, Jinghui; Liu, Jia-Ming; Yu, Mingbin; Lo, Guoqiang; Kwong, Dim-Lee; Xia, Guangqiong; Wong, Chee Wei
2016-01-01
Chaos has revolutionized the field of nonlinear science and stimulated foundational studies from neural networks, extreme event statistics, to physics of electron transport. Recent studies in cavity optomechanics provide a new platform to uncover quintessential architectures of chaos generation and the underlying physics. Here we report the first generation of dynamical chaos in silicon optomechanical oscillators, enabled by the strong and coupled nonlinearities of Drude electron-hole plasma. Deterministic chaotic oscillation is achieved, and statistical and entropic characterization quantifies the complexity of chaos. The correlation dimension D2 is determined at ~ 1.67 for the chaotic attractor, along with a maximal Lyapunov exponent rate about 2.94*the fundamental optomechanical oscillation. The corresponding nonlinear dynamical maps demonstrate the plethora of subharmonics, bifurcations, and stable regimes, along with distinct transitional routes into chaotic states. The chaos generation in our mesoscopic...
Replication of chaos in neural networks, economics and physics
Akhmet, Marat
2016-01-01
This book presents detailed descriptions of chaos for continuous-time systems. It is the first-ever book to consider chaos as an input for differential and hybrid equations. Chaotic sets and chaotic functions are used as inputs for systems with attractors: equilibrium points, cycles and tori. The findings strongly suggest that chaos theory can proceed from the theory of differential equations to a higher level than previously thought. The approach selected is conducive to the in-depth analysis of different types of chaos. The appearance of deterministic chaos in neural networks, economics and mechanical systems is discussed theoretically and supported by simulations. As such, the book offers a valuable resource for mathematicians, physicists, engineers and economists studying nonlinear chaotic dynamics.
Quantitative and qualitative Kac's chaos on the Boltzmann's sphere
Carrapatoso, Kleber
2012-01-01
We investigate the construction of chaotic probability measures on the Boltzmann's sphere, which is the state space of the stochastic process of a many-particle system undergoing a dynamics preserving energy and momentum. Firstly, based on a version of the local Central Limit Theorem (or Berry-Essenn theorem), we construct a sequence of probabilities that is Kac chaotic and we prove a quantitative rate of convergence. Then, we investigate a stronger notion of chaos, namely entropic chaos introduced in \\cite{CCLLV}, and we prove, with quantitative rate, that this same sequence is also entropically chaotic. Furthermore, we investigate more general class of probability measures on the Boltzmann's sphere. Using the HWI inequality we prove that a Kac chaotic probability with bounded Fisher's information is entropically chaotic and we give a quantitative rate. We also link different notions of chaos, proving that Fisher's information chaos, introduced in \\cite{HaurayMischler}, is stronger than entropic chaos, which...
ORDER IN THE CHAOS IN SPORTS ORGANIZATIONS
Directory of Open Access Journals (Sweden)
Mehran Azarian
2014-07-01
Full Text Available Purpose: Nowadays, scientists consider the world as a combination of some systems that work in a self -organizing way and the result of such a way is unpredictable and accidential states. Compulsory Natural rules are affective in such circumstances. Also it is known that systems work in a circular form in which order ends in disorder and vice versa. The idea of world as something simple has already replaced by a complicated and contradictory world. The study aim is to survey chaordic organizations characters of sport organizations. Materials and methods : For this purpose we used a standard questionnaire with appropriate reliability and validity. The statistical population of the study are whole staff of sport and youth head-quarter of west Azarbaijan province that are 89 (sample number is equal to the population's. We used Kolmogrov- Smirnov test to study data normal distribution, and in respect of normal distribution of data to test hypothesis we used sample t test and also descriptive statistical methods like mean and standard deviation, through SPSS 18. Questionnaires were filled out by whole staff of sport and youth head-quarters of west Azarbaijan province. Results: Results of this study, which have got through a single-sample t-test, show that sport organizations have six characteristics of welcoming to innovation, coherence, uncertainty, non-linearity, unpredictability, and ugly structure. It’s just the grade of the characteristic of recruiting competent staffs that is low in sport organizations; in fact they don’t enjoy it. But, within assessing the main hypothesis of the research that was around the feature of chaos-order, it was resulted that sport organizations have characteristics of a chaos-order organization and they can be considered as a chaos-order organization. Conclusions: According to the results of this study and t-table we can deduce that sport organizations are chaordic organization.
Asano, Yuhma; Kawai, Daisuke; Yoshida, Kentaroh
2015-06-01
We study classical chaotic motions in the Berenstein-Maldacena-Nastase (BMN) matrix model. For this purpose, it is convenient to focus upon a reduced system composed of two-coupled anharmonic oscillators by supposing an ansatz. We examine three ansätze: 1) two pulsating fuzzy spheres, 2) a single Coulomb-type potential, and 3) integrable fuzzy spheres. For the first two cases, we show the existence of chaos by computing Poincaré sections and a Lyapunov spectrum. The third case leads to an integrable system. As a result, the BMN matrix model is not integrable in the sense of Liouville, though there may be some integrable subsectors.
Asano, Yuhma; Yoshida, Kentaroh
2015-01-01
We study classical chaotic motions in the Berenstein-Maldacena-Nastase (BMN) matrix model. For this purpose, it is convenient to focus upon a reduced system composed of two-coupled anharmonic oscillators by supposing an ansatz. We examine three ans\\"atze: 1) two pulsating fuzzy spheres, 2) a single Coulomb-type potential, and 3) integrable fuzzy spheres. For the first two cases, we show the existence of chaos by computing Poincar\\'e sections and a Lyapunov spectrum. The third case leads to an integrable system. As a result, the BMN matrix model is not integrable in the sense of Liouville, though there may be some integrable subsectors.
Topological organization of (low-dimensional) chaos
International Nuclear Information System (INIS)
Recent progress toward classifying low-dimensional chaos measured from time series data is described. This classification theory assigns a template to the time series once the time series is embedded in three dimensions. The template describes the primary folding and stretching mechanisms of phase space responsible for the chaotic motion. Topological invariants of the unstable periodic orbits in the closure of the strange set are calculated from the (reconstructed) template. These topological invariants must be consistent with ampersand ny model put forth to describe the time series data, and are useful in invalidating (or gaining confidence in) any model intended to describe the dynamical system generating the time series
Time reversibility, computer simulation, and chaos
Hoover, William Graham
1999-01-01
A small army of physicists, chemists, mathematicians, and engineers has joined forces to attack a classic problem, the "reversibility paradox", with modern tools. This book describes their work from the perspective of computer simulation, emphasizing the author's approach to the problem of understanding the compatibility, and even inevitability, of the irreversible second law of thermodynamics with an underlying time-reversible mechanics. Computer simulation has made it possible to probe reversibility from a variety of directions and "chaos theory" or "nonlinear dynamics" has supplied a useful
Delayed self-synchronization in homoclinic chaos
Arecchi, F. T.; Meucci, R.; Allaria, E.; di Garbo, A.; Tsimring, L. S.
2002-04-01
The chaotic spike train of a homoclinic dynamical system is self-synchronized by applying a time-delayed correction proportional to the laser output intensity. Due to the sensitive nature of the homoclinic chaos to external perturbations, stabilization of very long-periodic orbits is possible. On these orbits, the dynamics appears chaotic over a finite time, but then it repeats with a recurrence time that is slightly longer than the delay time. The effect, called delayed self-synchronization, displays analogies with neurodynamic events that occur in the buildup of long-term memories.
A new optimization algorithm based on chaos
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
In this article, some methods are proposed for enhancing the converging velocity of the COA (chaos optimization algorithm) based on using carrier wave two times, which can greatly increase the speed and efficiency of the first carrier wave's search for the optimal point in implementing the sophisticated searching during the second carrier wave is faster and more accurate.In addition, the concept of using the carrier wave three times is proposed and put into practice to tackle the multi-variables optimization problems, where the searching for the optimal point of the last several variables is frequently worse than the first several ones.
Bose-Hubbard Hamiltonian: Quantum chaos approach
Kolovsky, Andrey R.
2016-03-01
We discuss applications of the theory of quantum chaos to one of the paradigm models of many-body quantum physics — the Bose-Hubbard (BH) model, which describes, in particular, interacting ultracold Bose atoms in an optical lattice. After preliminary, pure quantum analysis of the system we introduce the classical counterpart of the BH model and the governing semiclassical equations of motion. We analyze these equations for the problem of Bloch oscillations (BOs) of cold atoms where a number of experimental results are available. The paper is written for nonexperts and can be viewed as an introduction to the field.
The CHAOS-4 Geomagnetic Field Model
Olsen, N.; Finlay, C. C.; Luhr, H.; Sabaka, T. J.; Michaelis, I.; Rauberg, J.; Tøffner-clausen, L.
2013-12-01
We present CHAOS-4, a new version in the CHAOS model series, which aims at describing the Earth's magnetic field with high spatial resolution (terms up to spherical degree n=90 for the crustal field, and up to n=16 for the time-varying core field are robustly determined) and high temporal resolution (allowing for investigations of sub-annual core field changes). More than 14 years of data from the satellites Ørsted (March 1999 to June 2013), CHAMP (July 2000 to September 2010) and SAC-C (2000 to 2004), augmented with ground observatory revised monthly mean values (1997 to 2013) have been used for this model. Maximum spherical harmonic degree of the static (crustal) field is n=100. The core field time changes are expressed by spherical harmonic expansion coefficients up to n=20, described by order 6 splines (with 6-month knot spacing) spanning the time interval 1997.0 to 2013.5. The third time derivative of the squared magnetic field intensity is regularized at the core-mantle boundary. No spatial regularization is applied for the core field, but the high-degree crustal field is regularized for n>85. As part of the modeling effort we co-estimate a model of the large-scale magnetospheric field (with expansions in the GSM and SM coordinate system up to degree n = 2 and parameterization of the time dependence using the decomposition of Dst into external (Est) and induced (Ist) parts) and perform an in-flight alignment of the vector data (co-estimation of the Euler describing the rotation between the coordinate systems of the vector magnetometer and of the star sensor providing attitude information). The final CHAOS-4 model is derived by merging two sub-models: its low-degree part has been obtained using similar model parameterization and data sets as used for previous CHAOS models (but of course including newer satellite observations), while its high-degree crustal field part is solely determined from low-altitude CHAMP satellite observations between January 2009 and
Chaos caused by fatigue crack growth
International Nuclear Information System (INIS)
The nonlinear dynamic responses including chaotic oscillations caused by a fatigue crack growth are presented. Fatigue tests have been conducted on a novel fatigue-testing rig, where the loading is generated from inertial forces. The nonlinearity is in the form of discontinuous stiffness caused by the opening and closing of a growing crack. Nonlinear dynamic tools such as Poincare maps and bifurcation diagrams are used to unveil the global dynamics of the system. The results obtained indicate that fatigue crack growth strongly influences the dynamic response of the system leading to chaos
Chaos caused by fatigue crack growth
Energy Technology Data Exchange (ETDEWEB)
Foong, C.-H.; Pavlovskaia, Ekaterina; Wiercigroch, Marian; Deans, William
2003-06-01
The nonlinear dynamic responses including chaotic oscillations caused by a fatigue crack growth are presented. Fatigue tests have been conducted on a novel fatigue-testing rig, where the loading is generated from inertial forces. The nonlinearity is in the form of discontinuous stiffness caused by the opening and closing of a growing crack. Nonlinear dynamic tools such as Poincare maps and bifurcation diagrams are used to unveil the global dynamics of the system. The results obtained indicate that fatigue crack growth strongly influences the dynamic response of the system leading to chaos.
Chaos Synchronization in Two Coupled Duffing Oscillators
Institute of Scientific and Technical Information of China (English)
方见树; 荣曼生; 方焯; 刘小娟
2001-01-01
We have obtained two general unstable periodic solutions near the homoclinic orbits of two coupled Duffing oscillators with weak periodic perturbations by using the direct perturbation technique. Theoretical analysis reveals that the stable periodic orbits are embedded in the Melnikov chaotic attractors. The corresponding numerical results show that the phase portraits in the (x, u) and (y, v) planes are identical and are synchronized when the parameters of the two coupled oscillators are identical, but they are different and asynchronized when there is any difference between these parameters. It has been shown that the system parameters play a very important role in chaos control and synchronization.
Quantum chaos and the black hole horizon
CERN. Geneva
2016-01-01
Thanks to AdS/CFT, the analogy between black holes and thermal systems has become a practical tool, shedding light on thermalization, transport, and entanglement dynamics. Continuing in this vein, recent work has shown how chaos in the boundary CFT can be analyzed in terms of high energy scattering right on the horizon of the dual black hole. The analysis revolves around certain out-of-time-order correlation functions, which are simple diagnostics of the butterfly effect. We will review this work, along with a general bound on these functions that implies black holes are the most chaotic systems in quantum mechanics. (NB Room Change to Main Auditorium)
Controlling chaos in Internet congestion control model
International Nuclear Information System (INIS)
The TCP end-to-end congestion control plus RED router queue management can be modeled as a discrete-time dynamical system, which may create complex bifurcating and chaotic behavior. Based on the basic features of the TCP-RED model, we propose a time-dependent delayed feedback control algorithm to control chaos in the system by perturbing the accessible RED parameter pmax. This method is able to stabilized a router queue occupancy at a level without knowing the exact knowledge of the network. Further, we study the situation of the presence of the UDP traffic
Enlightening complexity: making energy with chaos
Molinari, D
2011-01-01
We study the energy harvesting of photons undergoing chaotic dynamics with different complexity degrees. Our theory employs a multiscale analysis, which combines Hamiltonian billiards, time-dependent coupled mode theory and ab-initio simulations. In analogy to classical thermodynamics, where the presence of microscopic chaos leads to a single direction for time and entropy, an increased complexity in the motion of photons yields to a monotonic accumulation of energy, which dramatically grows thanks to a constructive mechanism of energy buildup. This result could lead to the realization of novel complexity-driven, energy harvesting architectures.
Importance of packing in spiral defect chaos
Indian Academy of Sciences (India)
Kapilanjan Krishna
2008-04-01
We develop two measures to characterize the geometry of patterns exhibited by the state of spiral defect chaos, a weakly turbulent regime of Rayleigh-Bénard convection. These describe the packing of contiguous stripes within the pattern by quantifying their length and nearest-neighbor distributions. The distributions evolve towards unique distribution with increasing Rayleigh number that suggests power-law scaling for the dynamics in the limit of infinite system size. The techniques are generally applicable to patterns that are reducible to a binary representation.
Congenital laryngomucocoele: a rare cause for CHAOS
M. Cunha; Janeiro, P; Fernandes, R.; Carreiro, H; Laurini, R
2009-01-01
Congenital high airway obstruction syndrome (CHAOS) is a rare but life-threatening condition that results from the obstruction of the upper airways. We describe a female newborn, from a Grávida II, Para 0, 36-year-old woman, with a routine ultrasound at 30 weeks’ gestation that showed polyhydramnios. She delivered a live-born female baby at 36 weeks without any dismorphic features but with respiratory distress. Attempts at endotracheal intubation were unsuccessful due to the presence of a ...
External-beam PIXE analysis of Chinese archaic jades and jade minerals%玉石及中国古代玉器的PIXE分析
Institute of Scientific and Technical Information of China (English)
张朱武; 承焕生; 干福熹
2009-01-01
本文用外束PIXE技术分析了中国古代玉器和玉石的主量、微量元素的种类和含量.实验结果表明,外束PIXE技术在判定古代玉器的玉料来源和区别不同产地玉石方面具有广阔的应用前景.%External-beam proton induced X-ray emission (PIXE) is a high-sensitive, non-destructive and multi-element quantitative analysis method, which can be used to analyze the variety and content of major and trace elements of Chinese archaic jades and jade mineral samples. In this paper, the analysis results of the variety and content of major and trace elements of several Chinese archaic jades and jade mineral samples are presented, which are shown that the external-beam PIXE can be a useful tool for identifying the geological formation of jade minerals and source of Chinese artifacts.
Directory of Open Access Journals (Sweden)
Benjamin John Burger
2013-10-01
Full Text Available A new species of an archaic primate (Pleisadapiformes is described based on a maxilla containing the first and second upper molars from the Fort Union Formation, Atwell Gulch Member in northwestern Colorado. The preserved teeth show the unusual dental characteristics of members of the rare and poorly documented Picrodontidae family, including an elongated centrocrista and wide occlusal surface. The new species is placed within the genus Zanycteris (represented by a single specimen from southern Colorado. This placement is based on similarities in regard to the parastyle, curvilinear centrocrista, and wider anterior stylar shelf on the upper molars. However, the new species differs from the only known species of Zanycteris in exhibiting an upper first molar that is 30% larger in area, while retaining a similarly sized upper second molar. Phylogenetic analysis supports the separation of the Picrodontidae family from the Paromomyidae, while still recognizing picrodontids position within Pleisadapiformes. The unusual dental features of the upper molars likely functioned in life as an enhanced shearing surface between the centrocrista and cristid obliqua crests for a specialized diet of fruit. A similar arrangement is found in the living bat Ariteus (Jamaican fig-eating bat, which feeds on fleshy fruit. The new species showcases the rapid diversification of archaic primates shortly after the extinction of the dinosaurs during the Paleocene, and the unusual dental anatomy of picrodontids to exploit new dietary specializations.
古韵歌月元三部关系研究述评%A Review of the Collocation of the Archaic Rhyme Ge, Yue and Yuan
Institute of Scientific and Technical Information of China (English)
王娇
2012-01-01
在上古音研究中,古音学家对阴声韵歌部,或祭部,或至部,与入声韵月部,阳声韵元部的搭配上一直存在不同的见解。本文将对各古音学家有关歌月元部的观点进行梳理,从古音学家在阴阳对转、考古与审音以及上古声调等方面入手,探析各古音学家歌月元部的成因。%In the study of archaic Chinese phonology, phonologists have different opinions about the colloca- tion of the Yin rhyme Ge, or Gi, or Zhi with the Ru rhyme Yue and the Yang rhyme Yuan. This paper sums up these opinions in order to probe into the causes of their formation in Ge, Yue and Yuan from the aspects of Yin and Yang displacement, archaeology, sound identification and archaic intonation, etc.
Staircase functions, spectral regidity and a rule for quantizing chaos
International Nuclear Information System (INIS)
Considering the Selberg trace formula as an exact version of Gutzwiller's semiclassical periodic-orbit theory in the case of the free motion on compact Riemann surfaces with constant negative curvature (Hadamard-Gutzwiller model), we study two complementary basic problems in quantum chaology: the computation of the calssical staircase N(l), the number of periodic orbits with length shorter than l, in terms of the quantal energy spectrum {En}, the computation of the spectral staircase N (E), the number of quantal energies below the energy E, in terms of the length spectrum {ln} of the classical periodic orbits. A formulation of the periodic-orbit theory is presented which is intrinsically unsmoothed, but for which an effective smoothing arises from the limited 'input data', i.e. from the limited knowledge of the periodic orbits in the case of N(E) and the limited knowledge of quantal energies in the case of N(l). Based on the periodic-orbit formula for N(E), we propose a new rule for quantizing chaos, which simply states that the quantal energies are determined by the zeros of the function ξ1(E) = cos (πN(E)). The formulas for N(l) and N(E) as well as the new quantization condition are tested numerically. Furthermore, it is shown that the staircase N(E) computed from the length spectrum yields (up to a constant) a good description of the spectral rigidity Δ3(L), being the first numerical attempt to compute a statistical property of the quantal energy spectrum of a chaotic system from classical periodic orbits. (orig.)
Experimental Chaos - Proceedings of the 3rd Conference
Harrison, Robert G.; Lu, Weiping; Ditto, William; Pecora, Lou; Spano, Mark; Vohra, Sandeep
1996-10-01
The Table of Contents for the full book PDF is as follows: * Preface * Spatiotemporal Chaos and Patterns * Scale Segregation via Formation of Domains in a Nonlinear Optical System * Laser Dynamics as Hydrodynamics * Spatiotemporal Dynamics of Human Epileptic Seizures * Experimental Transition to Chaos in a Quasi 1D Chain of Oscillators * Measuring Coupling in Spatiotemporal Dynamical Systems * Chaos in Vortex Breakdown * Dynamical Analysis * Radial Basis Function Modelling and Prediction of Time Series * Nonlinear Phenomena in Polyrhythmic Hand Movements * Using Models to Diagnose, Test and Control Chaotic Systems * New Real-Time Analysis of Time Series Data with Physical Wavelets * Control and Synchronization * Measuring and Controlling Chaotic Dynamics in a Slugging Fluidized Bed * Control of Chaos in a Laser with Feedback * Synchronization and Chaotic Diode Resonators * Control of Chaos by Continuous-time Feedback with Delay * A Framework for Communication using Chaos Sychronization * Control of Chaos in Switching Circuits * Astrophysics, Meteorology and Oceanography * Solar-Wind-Magnetospheric Dynamics via Satellite Data * Nonlinear Dynamics of the Solar Atmosphere * Fractal Dimension of Scalar and Vector Variables from Turbulence Measurements in the Atmospheric Surface Layer * Mechanics * Escape and Overturning: Subtle Transient Behavior in Nonlinear Mechanical Models * Organising Centres in the Dynamics of Parametrically Excited Double Pendulums * Intermittent Behaviour in a Heating System Driven by Phase Transitions * Hydrodynamics * Size Segregation in Couette Flow of Granular Material * Routes to Chaos in Rotational Taylor-Couette Flow * Experimental Study of the Laminar-Turbulent Transition in an Open Flow System * Chemistry * Order and Chaos in Excitable Media under External Forcing * A Chemical Wave Propagation with Accelerating Speed Accompanied by Hydrodynamic Flow * Optics * Instabilities in Semiconductor Lasers with Optical Injection * Spatio
Intrinsic Angular Momentum of Light.
Santarelli, Vincent
1979-01-01
Derives a familiar torque-angular momentum theorem for the electromagnetic field, and includes the intrinsic torques exerted by the fields on the polarized medium. This inclusion leads to the expressions for the intrinsic angular momentum carried by the radiation traveling through a charge-free medium. (Author/MA)
The dream's navel between chaos and thought.
Scalzone, F; Zontini, G
2001-04-01
The authors begin by drawing attention to the problem of the transition from the biological to the psychic, noting that Freud himself, with his background in the neurosciences, grappled with it throughout his career. Certain recent paradigms more commonly applied to the natural sciences, such as in particular chaos and complexity theory, can in their view prove fruitful in psychoanalysis too, and it is shown how these notions are inherent in some of Freud's conceptions. The unconscious is stated to operate like a neural network, performing the kind of parallel processing used in the computing of highly complex situations, whereas the conscious mind is sequential. Dreams, in the authors' opinion, are organisers of the mind, imparting order to the turbulence of the underlying wishes and unconscious fantasies and structuring them through the dream work. Through dreams, the structured linearity of conscious thought can emerge out of the non-linear chaos of the drives. The dream's navel can be seen as the chaotic link, or interface, between the unconscious wish, which constitutes an attractor, and the conscious thought. The attractor may be visualised as having an hourglass or clepsydra shape, the narrow section being the dream's navel, and, being the same at any scale of observation, has the property of fractality. PMID:11341062
Order and chaos in soft condensed matter
Indian Academy of Sciences (India)
A K Sood; Rajesh Ganapathy
2006-07-01
Soft matter, like colloidal suspensions and surfactant gels, exhibit strong response to modest external perturbations. This paper reviews our recent experiments on the nonlinear flow behaviour of surfactant worm-like micellar gels. A rich dynamic behaviour exhibiting regular, quasi-periodic, intermittency and chaos is observed. In particular, we have shown experimentally that the route to chaos is via Type-II intermittency in shear thinning worm-like micellar solution of cetyltrimethylammonium tosylate where the strength of flow-concentration coupling is tuned by the addition of sodium chloride. A Poincaré first return map of the time series and the probability distribution of laminar length between burst events show that our data are consistent with Type-II intermittency. The existence of a `Butterfly' intensity pattern in small angle light scattering (SALS) measurements performed simultaneously with the rheological measurements confirms the coupling of flow to concentration fluctuations in the system under study. The scattered depolarised intensity in SALS, sensitive to orientational order fluctuations, shows the same time-dependence (like intermittency) as that of shear stress.
Chaos and structure of level densities
Energy Technology Data Exchange (ETDEWEB)
Moller, Peter [Los Alamos National Laboratory; Aberg, Sven [LUND SWEDEN; Uhrenholt, Henrik [LUND SWEDEN; Ickhikawa, Takatoshi [RIKEN
2008-01-01
The energy region of the first few MeV above the ground state shows interesting features of the nucleus. Beyond an ordered energy region just above the ground-state the dynamics changes, and chaotic features are observed in the neutron resonance region. The statistical properties of energies and wave-functions are common to all chaotic nuclei. However, if instead a global property, like the local level-density function is studied, strong structure effects emerge. In this contribution we discuss these two different facets of warm nuclei. In section 2 the onset of chaos with increasing excitation energy is discussed, with both experimental observations and proposed theoretical mechanisms as starting points. The structure of level densities in the same excitation energy region based on the two different starting points, is treated in section 3, where we give a short presentation of a newly developed combinatorial level-density modell. Some results from the model are presented and discussed. Two coexisting facets of warm nuclei, quantum chaos and structure of the level density, are considered. A newly developed combinatorial level-density model is presented, and the role of collective enhancements discussed. An example of extreme parity enhancement is shown.
Equilibrium behavior of coarse-grained chaos
Egolf, David A.; Ballard, Christopher C.; Esty, C. Clark
2015-03-01
A wide variety of systems exhibiting spatiotemporal chaos have been shown to be extensive, in that their fractal dimensions grow linearly with volume. Ruelle argued that this extensivity is evidence that these systems can be viewed as a gas of weakly-interacting regions. We have tested this idea by performing large-scale computational studies of spatiotemporal chaos in the 1D complex Ginzburg-Landau equation, and we have found that aspects of the coarse-grained system are well-described not only as a gas, but as an equilibrium gas -- in particular, a Tonks gas (and variants) in the grand canonical ensemble. Furthermore, for small system sizes, the average number of particles in the corresponding Tonks gas exhibits oscillatory, decaying deviations from extensivity in agreement with deviations in the fractal dimension found by Fishman and Egolf. This result not only supports Ruelle's picture but also suggests that the coarse-grained behavior of this far-from-equilibrium system might be understood using equilibrium statistical mechanics.
Decrease of cardiac chaos in congestive heart failure
Poon, Chi-Sang; Merrill, Christopher K.
1997-10-01
The electrical properties of the mammalian heart undergo many complex transitions in normal and diseased states. It has been proposed that the normal heartbeat may display complex nonlinear dynamics, including deterministic chaos,, and that such cardiac chaos may be a useful physiological marker for the diagnosis and management, of certain heart trouble. However, it is not clear whether the heartbeat series of healthy and diseased hearts are chaotic or stochastic, or whether cardiac chaos represents normal or abnormal behaviour. Here we have used a highly sensitive technique, which is robust to random noise, to detect chaos. We analysed the electrocardiograms from a group of healthy subjects and those with severe congestive heart failure (CHF), a clinical condition associated with a high risk of sudden death. The short-term variations of beat-to-beat interval exhibited strongly and consistently chaotic behaviour in all healthy subjects, but were frequently interrupted by periods of seemingly non-chaotic fluctuations in patients with CHF. Chaotic dynamics in the CHF data, even when discernible, exhibited a high degree of random variability over time, suggesting a weaker form of chaos. These findings suggest that cardiac chaos is prevalent in healthy heart, and a decrease in such chaos may be indicative of CHF.
HOPF BIFURCATION AND CHAOS OF FINANCIAL SYSTEM ON CONDITION OF SPECIFIC COMBINATION OF PARAMETERS
Institute of Scientific and Technical Information of China (English)
Junhai MA; Yaqiang CUI; Lixia LIU
2008-01-01
This paper studies the global bifurcation and Hopf bifurcation of one kind of complicated financial system with different parameter combinations. Conditions on which bifurcation happens, and the critical system structure when the system transforms from one kind of topological structure to another are studied as well. The criterion for identifying Hopf bifurcation under different parameter combinations is also given. The chaotic character of this system under quasi-periodic force is finally studied. The bifurcation structure graphs are given when two parameters of the combination are fixed while the other parameter varies. The presence and stability of 2 and 3 dimensional torus bifurcation are studied. All of the Lyapunov exponents of the system with different bifurcation parameters and routes leading the system to chaos with different parameter combinations are studied. It is of important theoretical and practical meaning to probe the intrinsic mechanism of such continuous complicated financial system and to find the macro control policies for such kind of system.
Study on Chaos Created by Hopf Bifurcation of One Kind of Financial System and Its Application
Institute of Scientific and Technical Information of China (English)
JunhaiMa; BiaoRen; YanGao
2004-01-01
From a mathematical model of one kind complicated financial system, corresponding local topological structures of such kind system on condition of certain parametercombination, unstable equilibrium point of the system, conditions on which Hopf bifurcation is created and stability of the limit circle corresponding to the Hopf bifurcation as well as condition on which the limit circle is stable have been studied. From relationship between each parameter and the Hopf bifurcation all the way to route which leads to chaos etc have been studied. Following the above, conditions on which complicated behaviors created locally in such kind system has been analyzed. By applying fractal dimension, Lyapunov index, the intrinsic complexity of the system on such condition has been studied, and result of the numerical simulation proves the theory of this paper correct.
Chaos in temporarily destabilized regular systems with the slow passage effect
International Nuclear Information System (INIS)
We provide evidences for chaotic behaviour in temporarily destabilized regular systems. In particular, we focus on time-continuous systems with the slow passage effect. The extreme sensitivity of the slow passage phase enables the existence of long chaotic transients induced by random pulsatile perturbations, thereby evoking chaotic behaviour in an initially regular system. We confirm the chaotic behaviour of the temporarily destabilized system by calculating the largest Lyapunov exponent. Moreover, we show that the newly obtained unstable periodic orbits can be easily controlled with conventional chaos control techniques, thereby guaranteeing a rich diversity of accessible dynamical states that is usually expected only in intrinsically chaotic systems. Additionally, we discuss the biological importance of presented results
CHAOS THEORY: A CONTRIBUTION TO THE FORMATION OF STRATEGIES
Directory of Open Access Journals (Sweden)
Marcio Luiz Marietto
2011-12-01
Full Text Available It is our intention, through this work, to contribute to the understanding of the influence of chaos theory on the formation of organizational strategies in the dynamic and complex environment in which organizations are embedded. In this sense, we present a theoretical review, leveraged by a dialectical epistemology, in which we propose to show some attributes of chaos theory and theoretical assumptions to be considered in the context of different areas of organizational strategy, with the goal of trying to elucidate and approximate the analytical characteristics of both theories and make evident how chaos theory can contribute to and/or influence the formation of business strategies.
Diffusive Lorenz dynamics： Coherent structures and spatiotemporal chaos
Institute of Scientific and Technical Information of China (English)
YuehongQIAN; HudongCHEN; Da-HsuanFENG
2000-01-01
In this paper, we are interested in collective behaviors of many interacting Lorenz strange attractors. With an intermediate diffusion coupling between the attractors,a new remarkable synchronization of well organized structures merges as a result of two competing mechanisms: temporal chaos and spatial diffusive stabilization. A window of the coupling parameter for coherent structures is found numerically. Different from all existing scenarios of routes to chaos (period doubling, intermittency and strange attractors), an algorithmetic increase of wavenumbers before an abrupt change to chaos (compared to the periodic doubling geometrical) is unexpectedly discovered. Meta-stable states are also observed in simulations.
Evolution to the Edge of Chaos in Imitation Game
Kaneko, K; Kaneko, Kunihiko; Suzuki, Junji
1993-01-01
Motivated by the evolution of complex bird songs, an abstract imitation game is proposed to study the increase of dynamical complexity: Artificial "birds" display a "song" time series to each other, and those that imitate the other's song better win the game. With the introduction of population dynamics according to the score of the game and the mutation of parameters for the song dynamics, the dynamics is found to evolve towards the borderline between chaos and a periodic window, after punctuated equilibria. The importance of edge of chaos with topological chaos for complexity is stressed.
Contributions of plasma physics to chaos and nonlinear dynamics
Escande, Dominique
2016-01-01
This topical review focusses on the contributions of plasma physics to chaos and nonlinear dynamics bringing new methods which are or can be used in other scientific domains. It starts with the development of the theory of Hamiltonian chaos, and then deals with order or quasi order, for instance adiabatic and soliton theories. It ends with a shorter account of dissipative and high dimensional Hamiltonian dynamics, and of quantum chaos. Most of these contributions are a spin-off of the research on thermonuclear fusion by magnetic confinement, which started in the fifties. Their presentation is both exhaustive and compact. [15 April 2016
New chaos-based encryption scheme for digital sequence
Institute of Scientific and Technical Information of China (English)
Zhang Zhengwei; Fan Yangyu; Zeng Li
2007-01-01
To enhance the anti-breaking performance of privacy information, this article proposes a new encryption method utilizing the leaping peculiarity of the periodic orbits of chaos systems. This method maps the secret sequence to several chaos periodic orbits, and a short sequence obtained by evolving the system parameters of the periodic orbits in another nonlinear system will be the key to reconstruct these periodic orbits. In the decryption end, the shadowing method of chaos trajectory based on the modified Newton-Raphson algorithm is adopted to restore these system parameters. Through deciding which orbit each pair coordinate falls on, the original digital sequence can be decrypted.
Chaos behavior in the discrete Fitzhugh nerve system
Institute of Scientific and Technical Information of China (English)
无
2001-01-01
The discrete Fitzhugh nerve systems obtained by the Euler method is investigated and it is proved that there exist chaotic phenomena in the sense of Marotto's definition of chaos. And numerical simulations not only show the consistence with the theoretical analysis but also exhibit the complex dynamical behaviors, including the ten-periodic orbit, a cascade of period-doubling bifurcation, quasiperiodic orbits and the chaotic orbits and intermittent chaos. The computations of Lyapunov exponents confirm the chaos behaviors. Moreover we also find a strange attractor having the self-similar orbit structure as that of Henon attractor.
Contributions of plasma physics to chaos and nonlinear dynamics
Escande, D. F.
2016-11-01
This topical review focusses on the contributions of plasma physics to chaos and nonlinear dynamics bringing new methods which are or can be used in other scientific domains. It starts with the development of the theory of Hamiltonian chaos, and then deals with order or quasi order, for instance adiabatic and soliton theories. It ends with a shorter account of dissipative and high dimensional Hamiltonian dynamics, and of quantum chaos. Most of these contributions are a spin-off of the research on thermonuclear fusion by magnetic confinement, which started in the fifties. Their presentation is both exhaustive and compact. [15 April 2016
From chaos to order methodologies, perspectives and applications
Chen Guan Rong
1998-01-01
Chaos control has become a fast-developing interdisciplinary research field in recent years. This book is for engineers and applied scientists who want to have a broad understanding of the emerging field of chaos control. It describes fundamental concepts, outlines representative techniques, provides case studies, and highlights recent developments, putting the reader at the forefront of current research.Important topics presented in the book include: Fundamentals of nonlinear dynamical systems, essential for understanding and developing chaos control methods.; Parametric variation and paramet
Controlling beam halo-chaos via backstepping design
Institute of Scientific and Technical Information of China (English)
Gao Yuan; Kong Feng
2008-01-01
A backstepping control method is proposed for controlling beam halo-chaos in the periodic focusing channels PFCs) of high-current ion accelerator. The analysis and numerical results show that the method, via adjusting an exterior magnetic field, is effective to control beam halo chaos with five types of initial distribution ion beams, all statistical quantities of the beam halo-chaos are largely reduced, and the uniformity of ion beam is improved. This control method has an important value of application, for the exterior magnetic field can be easily adjusted in the periodical magnetic focusing channels in experiment.
Quantum Chaos in Physical Systems from Super Conductors to Quarks
Bittner, E; Pullirsch, R; Bittner, Elmar; Markum, Harald; Pullirsch, Rainer
2001-01-01
This article is the written version of a talk delivered at the Bexbach Colloquium of Science 2000 and starts with an introduction into quantum chaos and its relationship to classical chaos. The Bohigas-Giannoni-Schmit conjecture is formulated and evaluated within random-matrix theory. Several examples of physical systems exhibiting quantum chaos ranging from nuclear to solid state physics are presented. The presentation concludes with recent research work on quantum chromodynamics and the quark-gluon plasma. In the case of a chemical potential the eigenvalue spectrum becomes complex and one has to deal with non-Hermitian random-matrix theory.
Energy Technology Data Exchange (ETDEWEB)
Medvinsky, Alexander B., E-mail: medvinsky@iteb.ru [Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino 142290, Moscow Region (Russian Federation); Rusakov, Alexey V. [Institute of Theoretical and Experimental Biophysics, Russian Academy of Sciences, Pushchino 142290, Moscow Region (Russian Federation)
2011-06-15
Highlights: > We model community dynamics in stateless societies. > Intercommunity barter is shown to be a factor impacting the societies dynamics. > Increase in the human population growth rate can lead to appearance of chaos. > Secular and millennial cycles are found to arise as a result of the barter. - Abstract: The once abstract notions of dynamical chaos now appear naturally in various systems [Kaplan D, Glass L. Understanding nonlinear dynamics. New York: Springer; 1995]. As a result, future trajectories of the systems may be difficult to predict. In this paper, we demonstrate the appearance of chaotic dynamics in model human communities, which consist of producers of agricultural product and producers of agricultural equipment. In the case of a solitary community, the horizon of predictability of the human population dynamics is shown to be dependent on both intrinsic instability of the dynamics and the chaotic attractor sizes. Since a separate community is usually a part of a larger commonality, we study the dynamics of social systems consisting of two interacting communities. We show that intercommunity barter can lead to stabilization of the dynamics in one of the communities, which implies persistence of stable equilibrium under changes of the maximum value of the human population growth rate. However, in the neighboring community, the equilibrium turns into a stable limit cycle as the maximum value of the human population growth rate increases. Following an increase in the maximum value of the human population growth rate leads to period-doubling bifurcations resulting in chaotic dynamics. The horizon of predictability of the chaotic oscillations is found to be limited by 5 years. We demonstrate that the intercommunity interaction can lead to the appearance of long-period harmonics in the chaotic time series. The period of the harmonics is of order 100 and 1000 years. Hence the long-period changes in the population size may be considered as an
Intrinsic time geometrodynamics: explicit examples
Lin, Huei-Chen
2016-01-01
Intrinsic time quantum geometrodynamics resolved `the problem of time' and bridged the deep divide between quantum mechanics and canonical quantum gravity with a Schrodinger equation which describes evolution in intrinsic time variable. In this formalism, Einstein's general relativity is a particular realization of a wider class of theories. Explicit classical black hole and cosmological solutions and the motion of test particles are derived and analyzed in this work in the context of constant three-curvature solutions in intrinsic time geometrodynamics; and we exemplify how this formalism yields results which agree with the predictions of Einstein's theory.
Chaos, Dirac observables and constraint quantization
Dittrich, Bianca; Koslowski, Tim A; Nelson, Mike I
2015-01-01
There is good evidence that full general relativity is non-integrable or even chaotic. We point out the severe repercussions: differentiable Dirac observables and a reduced phase space do not exist in non-integrable constrained systems and are thus unlikely to occur in a generic general relativistic context. Instead, gauge invariant quantities generally become discontinuous, thus not admitting Poisson-algebraic structures and posing serious challenges to a quantization. Non-integrability also renders the paradigm of relational dynamics cumbersome, thereby straining common interpretations of the dynamics. We illustrate these conceptual and technical challenges with simple toy models. In particular, we exhibit reparametrization invariant models which fail to be integrable and, as a consequence, can either not be quantized with standard methods or lead to sick quantum theories without a semiclassical limit. These troubles are qualitatively distinct from semiclassical subtleties in unconstrained quantum chaos and...
Spatial chaos-based image encryption design
Institute of Scientific and Technical Information of China (English)
LIU ShuTang; SUN FuYan
2009-01-01
In recent years, the chaos based cryptographic algorithms have suggested some new and efficient ways to develop secure image encryption techniques, but the drawbacks of small key space and weak security in one-dimensional chaotic cryptosystems are obvious. In this paper, permutation and sub-stitution methods are incorporated to present a stronger image encryption algorithm. Spatial chaotic maps are used to realize the position permutation, and to confuse the relationship between the ci-pher-image and the plain-image. The experimental results demonstrate that the suggested encryption scheme of image has the advantages of large key space and high security; moreover, the distribution of grey values of the encrypted image has a random-like behavior.
Chaos synchronization based on intermittent state observer
Institute of Scientific and Technical Information of China (English)
Li Guo-Hui; Zhou Shi-Ping; Xu De-Ming
2004-01-01
This paper describes the method of synchronizing slave to the master trajectory using an intermittent state observer by constructing a synchronizer which drives the response system globally tracing the driving system asymptotically. It has been shown from the theory of synchronization error-analysis that a satisfactory result of chaos synchronization is expected under an appropriate intermittent period and state observer. Compared with continuous control method,the proposed intermittent method can target the desired orbit more efficiently. The application of the method is demonstrated on the hyperchaotic Rossler systems. Numerical simulations show that the length of the synchronization interval rs is of crucial importance for our scheme, and the method is robust with respect to parameter mismatch.
Food chain chaos due to transcritical point
Deng, Bo; Hines, Gwendolen
2003-06-01
Chaotic dynamics of a classical prey-predator-superpredator ecological model are considered. Although much is known about the behavior of the model numerically, very few results have been proven analytically. A new analytical result is obtained. It is demonstrated that there exists a subset on which a singular Poincaré map generated by the model is conjugate to the shift map on two symbols. The existence of such a Poincaré map is due to two conditions: the assumption that each species has its own time scale ranging from fast for the prey to slow for the superpredator, and the existence of transcritical points, leading to the classical mathematical phenomenon of Pontryagin's delay of loss of stability. This chaos generating mechanism is new, neither suspected in abstract form nor recognized in numerical experiments in the literature.
Mechanics From Newton's Laws to Deterministic Chaos
Scheck, Florian
2010-01-01
This book covers all topics in mechanics from elementary Newtonian mechanics, the principles of canonical mechanics and rigid body mechanics to relativistic mechanics and nonlinear dynamics. It was among the first textbooks to include dynamical systems and deterministic chaos in due detail. As compared to the previous editions the present fifth edition is updated and revised with more explanations, additional examples and sections on Noether's theorem. Symmetries and invariance principles, the basic geometric aspects of mechanics as well as elements of continuum mechanics also play an important role. The book will enable the reader to develop general principles from which equations of motion follow, to understand the importance of canonical mechanics and of symmetries as a basis for quantum mechanics, and to get practice in using general theoretical concepts and tools that are essential for all branches of physics. The book contains more than 120 problems with complete solutions, as well as some practical exa...
Controlling chaos using an exponential control
Gadre, S D; Gadre, Sangeeta D; Varma, V S
1995-01-01
We demonstrate that chaos can be controlled using a multiplicative exponential feedback control. All three types of unstable orbits - unstable fixed points, limit cycles and chaotic trajectories can be stabilized using this control. The control is effective both for maps and flows. The control is significant, particularly for systems with several degrees of freedom, as knowledge of only one variable on the desired unstable orbit is sufficient to settle the system on to that orbit. We find, that in all the cases studied, the transient time is a decreasing function of the stiffness of control. But increasing the stiffness beyond an optimum value can increase the transient time. The control can also be used to create suitable new stable attractors in a map, which did not exist in the original system.
Chaos in body-vortex interactions
DEFF Research Database (Denmark)
Pedersen, Johan Rønby; Aref, Hassan
2010-01-01
The model of body–vortex interactions, where the fluid flow is planar, ideal and unbounded, and the vortex is a point vortex, is studied. The body may have a constant circulation around it. The governing equations for the general case of a freely moving body of arbitrary shape and mass density...... of a circle is integrable. As the body is made slightly elliptic, a chaotic region grows from an unstable relative equilibrium of the circle-vortex case. The case of a cylindrical body of any shape moving in fluid otherwise at rest is also integrable. A second transition to chaos arises from the limit between...... and an arbitrary number of point vortices are presented. The case of a body and a single vortex is then investigated numerically in detail. In this paper, the body is a homogeneous, elliptical cylinder. For large body–vortex separations, the system behaves much like a vortex pair regardless of body shape. The case...
Digital Communications Using Chaos and Nonlinear Dynamics
Larson, Lawrence E; Liu, Jia-Ming
2006-01-01
This book introduces readers to a new and exciting cross-disciplinary field of digital communications with chaos. This field was born around 15 years ago, when it was first demonstrated that nonlinear systems which produce complex non-periodic noise-like chaotic signals, can be synchronized and modulated to carry useful information. Thus, chaotic signals can be used instead of pseudo-random digital sequences for spread-spectrum and private communication applications. This deceptively simple idea spun hundreds of research papers, and many novel communication schemes based on chaotic signals have been proposed. However, only very recently researchers have begun to make a transition from academic studies toward practical implementation issues, and many "promising" schemes had to be discarded or re-formulated. This book describes the state of the art (both theoretical and experimental) of this novel field. The book is written by leading experts in the fields of Nonlinear Dynamics and Electrical Engineering who pa...
Time reversibility, computer simulation, algorithms, chaos
Hoover, William Graham
2012-01-01
A small army of physicists, chemists, mathematicians, and engineers has joined forces to attack a classic problem, the "reversibility paradox", with modern tools. This book describes their work from the perspective of computer simulation, emphasizing the author's approach to the problem of understanding the compatibility, and even inevitability, of the irreversible second law of thermodynamics with an underlying time-reversible mechanics. Computer simulation has made it possible to probe reversibility from a variety of directions and "chaos theory" or "nonlinear dynamics" has supplied a useful vocabulary and a set of concepts, which allow a fuller explanation of irreversibility than that available to Boltzmann or to Green, Kubo and Onsager. Clear illustration of concepts is emphasized throughout, and reinforced with a glossary of technical terms from the specialized fields which have been combined here to focus on a common theme. The book begins with a discussion, contrasting the idealized reversibility of ba...
Stochastic chaos in a turbulent swirling flow
Faranda, Davide; Saint-Michel, Brice; Wiertel, Cecile; Padilla, Vincent; Dubrulle, Berengere; Daviaud, Francois
2016-01-01
We report the experimental evidence of the existence of a random attractor in a fully developed turbulent swirling flow. By defining a global observable which tracks the asymmetry in the flux of angular momentum imparted to the flow, we can first reconstruct the associated turbulent attractor and then follow its route towards chaos. We further show that the experimental attractor can be modeled by stochastic Duffing equations, that match the quantitative properties of the experimental flow, namely the number of quasi-stationary states and transition rates among them, the effective dimensions, and the continuity of the first Lyapunov exponents. Such properties can neither be recovered using deterministic models nor using stochastic differential equations based on effective potentials obtained by inverting the probability distributions of the experimental global observables. Our findings open the way to low dimensional modeling of systems featuring a large number of degrees of freedom and multiple quasi-station...
Spatial chaos-based image encryption design
Institute of Scientific and Technical Information of China (English)
无
2009-01-01
In recent years, the chaos based cryptographic algorithms have suggested some new and efficient ways to develop secure image encryption techniques, but the drawbacks of small key space and weak security in one-dimensional chaotic cryptosystems are obvious. In this paper, permutation and sub- stitution methods are incorporated to present a stronger image encryption algorithm. Spatial chaotic maps are used to realize the position permutation, and to confuse the relationship between the ci- pher-image and the plain-image. The experimental results demonstrate that the suggested encryption scheme of image has the advantages of large key space and high security; moreover, the distribution of grey values of the encrypted image has a random-like behavior.
Strategic leadership: a view from quantum and chaos theories.
McDaniel, R R
1997-01-01
Viewing health care from the perspective of chaos and quantum theories offers new insights into management techniques for effective and efficient delivery of health care services. This article introduces these concepts and gives specific prescriptions for managerial action. PMID:9058085
Extension of spatiotemporal chaos in glow discharge-semiconductor systems
Energy Technology Data Exchange (ETDEWEB)
Akhmet, Marat, E-mail: marat@metu.edu.tr; Fen, Mehmet Onur [Department of Mathematics, Middle East Technical University, 06800 Ankara (Turkey); Rafatov, Ismail [Department of Physics, Middle East Technical University, 06800 Ankara (Turkey)
2014-12-15
Generation of chaos in response systems is discovered numerically through specially designed unidirectional coupling of two glow discharge-semiconductor systems. By utilizing the auxiliary system approach, [H. D. I. Abarbanel, N. F. Rulkov, and M. M. Sushchik, Phys. Rev. E 53, 4528–4535 (1996)] it is verified that the phenomenon is not a chaos synchronization. Simulations demonstrate various aspects of the chaos appearance in both drive and response systems. Chaotic control is through the external circuit equation and governs the electrical potential on the boundary. The expandability of the theory to collectives of glow discharge systems is discussed, and this increases the potential of applications of the results. Moreover, the research completes the previous discussion of the chaos appearance in a glow discharge-semiconductor system [D. D. Šijačić U. Ebert, and I. Rafatov, Phys. Rev. E 70, 056220 (2004).].
Complex Nonlinearity Chaos, Phase Transitions, Topology Change and Path Integrals
Ivancevic, Vladimir G
2008-01-01
Complex Nonlinearity: Chaos, Phase Transitions, Topology Change and Path Integrals is a book about prediction & control of general nonlinear and chaotic dynamics of high-dimensional complex systems of various physical and non-physical nature and their underpinning geometro-topological change. The book starts with a textbook-like expose on nonlinear dynamics, attractors and chaos, both temporal and spatio-temporal, including modern techniques of chaos–control. Chapter 2 turns to the edge of chaos, in the form of phase transitions (equilibrium and non-equilibrium, oscillatory, fractal and noise-induced), as well as the related field of synergetics. While the natural stage for linear dynamics comprises of flat, Euclidean geometry (with the corresponding calculation tools from linear algebra and analysis), the natural stage for nonlinear dynamics is curved, Riemannian geometry (with the corresponding tools from nonlinear, tensor algebra and analysis). The extreme nonlinearity – chaos – corresponds to th...
Filtering with Marked Point Process Observations via Poisson Chaos Expansion
International Nuclear Information System (INIS)
We study a general filtering problem with marked point process observations. The motivation comes from modeling financial ultra-high frequency data. First, we rigorously derive the unnormalized filtering equation with marked point process observations under mild assumptions, especially relaxing the bounded condition of stochastic intensity. Then, we derive the Poisson chaos expansion for the unnormalized filter. Based on the chaos expansion, we establish the uniqueness of solutions of the unnormalized filtering equation. Moreover, we derive the Poisson chaos expansion for the unnormalized filter density under additional conditions. To explore the computational advantage, we further construct a new consistent recursive numerical scheme based on the truncation of the chaos density expansion for a simple case. The new algorithm divides the computations into those containing solely system coefficients and those including the observations, and assign the former off-line.
CHAOS-BASED FEEDFORWARD OUTPUT FUNCTIONS FOR COMBINING KEYSTREAM GENERATORS
Institute of Scientific and Technical Information of China (English)
Sang Tao; Wang Ruli; Yan Yixun
2001-01-01
The chaos-based feedforward output functions for combining keystream generators are proposed according to chaotic dynamic theory. The generated binary signals are independently and identically distributed, and have predictable periods. All experiments correspond to the theoretical prediction very well.
The transition to chaos conservative classical systems and quantum manifestations
Reichl, Linda E
2004-01-01
This book provides a thorough and comprehensive discussion of classical and quantum chaos theory for bounded systems and for scattering processes Specific discussions include • Noether’s theorem, integrability, KAM theory, and a definition of chaotic behavior • Area-preserving maps, quantum billiards, semiclassical quantization, chaotic scattering, scaling in classical and quantum dynamics, dynamic localization, dynamic tunneling, effects of chaos in periodically driven systems and stochastic systems • Random matrix theory and supersymmetry The book is divided into several parts Chapters 2 through 4 deal with the dynamics of nonlinear conservative classical systems Chapter 5 and several appendices give a thorough grounding in random matrix theory and supersymmetry techniques Chapters 6 and 7 discuss the manifestations of chaos in bounded quantum systems and open quantum systems respectively Chapter 8 focuses on the semiclassical description of quantum systems with underlying classical chaos, and Chapt...
Fractional Chaos Based Communication Systems-An Introduction
Institute of Scientific and Technical Information of China (English)
Juebang Yu
2008-01-01
As one of secure communication means, chaotic communication systems has been well-developed during the past three decades. Technical papers, both for theoretical and practical investigations, have reached a huge amount in number. On the other hand, fractional chaos, as a parallel ongoing research topic, also attracts many researchers to investigate. As far as the IT field is concerned, the research on control systems by using fractional chaos known as FOC (fractional order control) has been a hot issue for quite a long time. As a comparison, interesting enough, up to now we have not found any research result related to Fractional Chaos Communi cation (FCC) system, Le., a system based on fractional chaos. The motivation of the present article is to reveal the feasibility of realizing communication systems based upon FCC and their superiority over the conventional integer chaotic communication systems. Principles of FCC and its advantages over integer chaotic communication systems are also discussed.
Discrete chaos in fractional sine and standard maps
Energy Technology Data Exchange (ETDEWEB)
Wu, Guo-Cheng, E-mail: wuguocheng@gmail.com [Key Laboratory of Numerical Simulation of Sichuan Province, College of Mathematics and Information Science, Neijiang Normal University, Neijiang 641112 (China); College of Water Resource and Hydropower, Sichuan University, Chengdu 610065 (China); Baleanu, Dumitru, E-mail: dumitru@cankaya.edu.tr [Department of Chemical and Materials Engineering, Faculty of Engineering, King Abdulaziz University, PO Box 80204, Jeddah 21589 (Saudi Arabia); Department of Mathematics and Computer Sciences, Faculty of Arts and Sciences, Cankaya University, 06530 Balgat, Ankara (Turkey); Institute of Space Sciences, Magurele-Bucharest (Romania); Zeng, Sheng-Da [School of Science, Guangxi University for Nationalities, Nanning 530006 (China)
2014-01-24
Fractional standard and sine maps are proposed by using the discrete fractional calculus. The chaos behaviors are then numerically discussed when the difference order is a fractional one. The bifurcation diagrams and the phase portraits are presented, respectively.
Chaos-assisted, broadband trapping of light in optical resonators
Liu, C; Molinari, D; Khan, Y; Ooi, B S; Krauss, T F; Fratalocchi, A
2012-01-01
Chaos is a phenomenon that occurs in many aspects of contemporary science. In classical dynamics, chaos is defined as a hypersensitivity to initial conditions. The presence of chaos is often unwanted, as it introduces unpredictability, which makes it difficult to predict or explain experimental results. Conversely, we demonstrate here how chaos can be used to enhance the ability of an optical resonator to store energy. We combine analytic theory with ab-initio simulations and experiments in photonic crystal resonators to show that a chaotic resonator can store six times more energy than its classical counterpart of the same volume. We explain the observed increase with the equipartition of energy among all degrees of freedom of the chaotic resonator, i.e. the cavity modes, which is evident from the convergence of their lifetime towards a single value. A compelling illustration of the theory is provided by demonstrating enhanced absorption in deformed polystyrene microspheres.
Biological conditions for oscillations and chaos generated by multispecies competition
Huisman, J; Weissing, FJ
2001-01-01
We investigate biological mechanisms that generate oscillations and chaos in multispecies competition models. For this purpose, we use a competition model concerned with competition for abiotic essential resources. Because phytoplankton and plants consume quite a number of abiotic essential resource
WHAT DOES CHAOS HAVE TO DO WITH SYSTEMS AND CONTROL ENGINEERING?
Institute of Scientific and Technical Information of China (English)
CHEN Guanrong
2001-01-01
Chaos as a very special type of complex dynamical behaviors hasbeen studied for about four decades. Yet the traditional trend of analyzing and understanding chaos has evolved to controlling and utilizing chaos today. Research in the field of chaos modeling,control, and synchronization includes not only ordering chaos, which means to weaken or completely suppress chaos when it is harmful, but also chaotification, which refers to enhancing existing chaos or creating chaos purposely when it is useful, by any means of control technology. This article offers a brief overview about the potential impact of controlled chaos on beneficial applications in science and engineering, and introduces some recent progress in chaotification via feedback control methods.
Intrinsic motivation and learning dynamics
Zgonnikov, Arkady
2013-01-01
We investigate the effects of intrinsic motivation on the dynamics of learning processes. We construct a simple model of a single agent adapting to unknown environment. Performing a repeated choice between a number of initially unexplored alternatives, the agent gains rewards for each selected alternative and in doing so gradually comprehends the environment. In our model the agent choice is governed by two stimuli. The traditional extrinsic motive inclines the agent to maximize the cumulative payoff throughout the process, while the second, intrinsic one, biases the agent towards the novel options that she inherently likes. We show that the intrinsic motivation can induce an instability and periodic dynamics of the learning process which is always stationary in the case of selfish, rational agent. Interestingly, the opposite effect can arise as well: when the impact of intrinsic motivation on the agent choice is strong, the equiprobable choice equilibrium strategy becomes stable. Based on the presented resul...
A Note on Intrinsic Correlation
Du, Songzi
2008-01-01
In this note we characterize the strategic implication of intrinsic correlation, introduced by Brandenburger and Friedenberg (2008), in the subjective correlated equilibrium setting of a complete information game. Intrinsic correlation restricts correlation devices to variables within the game, i.e. players's beliefs (and higher order beliefs) about each other's strategies, in contrast to signals or sunspots from the "outside." The characterization is a strengthening of best-response set wi...
Harmonic structures and intrinsic torsion
DEFF Research Database (Denmark)
Conti, Diego; Madsen, Thomas Bruun
2015-01-01
We discuss the construction of Sp(2)Sp(1)-structures whose fundamental form is closed. In particular, we find 10 new examples of 8-dimensional nilmanifolds that admit an invariant closed 4-form with stabiliser Sp(2) Sp(1). Our constructions entail the notion of SO(4)-structures on 7-manifolds. We...... present a thorough investigation of the intrinsic torsion of such structures, leading to the construction of explicit Lie group examples with invariant intrinsic torsion....
Harmonic structures and intrinsic torsion
DEFF Research Database (Denmark)
Conti, Diego; Madsen, Thomas Bruun
We discuss the construction of 8-manifolds with harmonic Sp(2)Sp(1)-structures. In particular, we find 10 new examples of nilmanifolds that admit a closed 4-form Omega whose stabiliser is Sp(2)Sp(1). Our constructions entail the notion of SO(4)-structures on 7-manifolds. We present a thorough inv...... investigation of the intrinsic torsion of such structures; in addition to the construction of harmonic structures, this analysis leads to explicit Lie group examples with invariant intrinsic torsion....
Bifurcations and chaos control in discrete small-world networks
Institute of Scientific and Technical Information of China (English)
Li Ning; Sun Hai-Yi; Zhang Qing-Ling
2012-01-01
An impulsive delayed feedback control strategy to control period-doubling bifurcations and chaos is proposed.The control method is then applied to a discrete small-world network model.Qualitative analyses and simulations show that under a generic condition,the bifurcations and the chaos can be delayed or eliminated completely.In addition,the periodic orbits embedded in the chaotic attractor can be stabilized.
Quantum Graphs: Applications to Quantum Chaos and Universal Spectral Statistics
Gnutzmann, Sven; Smilansky, Uzy
2006-01-01
During the last years quantum graphs have become a paradigm of quantum chaos with applications from spectral statistics to chaotic scattering and wave function statistics. In the first part of this review we give a detailed introduction to the spectral theory of quantum graphs and discuss exact trace formulae for the spectrum and the quantum-to-classical correspondence. The second part of this review is devoted to the spectral statistics of quantum graphs as an application to quantum chaos. E...
Secure Communication System Based on Chaos in Optical Fibre
Institute of Scientific and Technical Information of China (English)
Pak; L; Chu; Fan; Zhang; William; Mak; Robust; Lai
2003-01-01
1 IntroductionRecently, there have been intense research activities on the study of synchronized chaos generated by fibre lasers and its application to secure communication systems. So far, all studies concentrate on two aspects: (1) the effect of the transmission channel between the transmitter and the receiver has been neglected, and (2) the chaos and the signal are carried by one wavelength. Both theoretical and experimental investigations make
Chaos suppression in a spin-torque nano-oscillator
Xu, H. Z.; Chen, X.; Liu, J.-M.
2008-11-01
We propose a novel practicable self-control scheme to suppress chaos in a spin-torque nano-oscillator in the presence of spin-polarized dc and ac. The magnetization dynamics is investigated by performing micromagnetic simulation. A complete chaos control diagram is obtained, indicating that employment of this proper self-control scheme over a broad frequency range of the ac can greatly reduce the degree of chaoticity in the oscillator.
Relations between distributional, Li-Yorke and {omega} chaos
Energy Technology Data Exchange (ETDEWEB)
Guirao, Juan Luis Garcia [Departamento de Matematica Aplicada y Estadistica, Universidad Politecnica de Cartagena, C/Paseo Alfonso XIII, 30203-Cartagena (Region de Murcia) (Spain)]. E-mail: juan.garcia@upct.es; Lampart, Marek [Mathematical Institute at Opava, Silesian University at Opava, Na Rybnicku 1, 746 01 Opava (Czech Republic)]. E-mail: marek.lampart@math.slu.cz
2006-05-15
The forcing relations between notions of distributional, Li-Yorke and {omega} chaos were studied by many authors. In this paper we summarize all known connections between these three different types of chaos and fulfill the results for general compact metric spaces by the construction of a selfmap on a compact perfect set which is {omega} chaotic, not distributionally chaotic and has zero topological entropy.
Fluctuations of Spatial Patterns as a Measure of Classical Chaos
Cao, Z J; Cao, Zhen; Hwa, Rudolph C.
1997-01-01
In problems where the temporal evolution of a nonlinear system cannot be followed, a method for studying the fluctuations of spatial patterns has been developed. That method is applied to well-known problems in deterministic chaos (the logistic map and the Lorenz model) to check its effectiveness in characterizing the dynamical behaviors. It is found that the indices $\\mu _q$ are as useful as the Lyapunov exponents in providing a quantitative measure of chaos.
Chaos and Nonlinear Dynamics in a Quantum Artificial Economy
Gonçalves, Carlos Pedro
2012-01-01
Chaos and nonlinear economic dynamics are addressed for a quantum coupled map lattice model of an artificial economy, with quantized supply and demand equilibrium conditions. The measure theoretic properties and the patterns that emerge in both the economic business volume dynamics' diagrams as well as in the quantum mean field averages are addressed and conclusions are drawn in regards to the application of quantum chaos theory to address signatures of chaotic dynamics in relevant discrete economic state variables.
OnN Kac's Chaos and Related Problems
Hauray, Maxime
2012-01-01
This paper is devoted to establish quantitative and qualitative estimates related to the notion of chaos as firstly formulated by M. Kac [37] in his study of mean-field limit for systems of N undistinguishable particles as N \\rightarrow \\infty. First, we quantitatively liken three usual measures of Kac's chaos, some involving the all N variables, other involving a finite fixed number of variables. The cornerstone of the proof is a new representation of the Monge-Kantorovich-Wasserstein (MKW) distance for symmetric N-particle probabilities in terms of the distance between the law of the associated empirical measures on the one hand, and a new estimate on some MKW distance on probability spaces endowed with a suitable Hilbert norm taking advantage of the associated good algebraic structure. Next, we define the notion of entropy chaos and Fisher information chaos in a similar way as defined by Carlen et al [17]. We show that Fisher information chaos is stronger than entropy chaos, which in turn is stronger than ...
Chaos Suppression in a Sine Square Map through Nonlinear Coupling
Institute of Scientific and Technical Information of China (English)
Eduardo L. Brugnago; Paulo C. Rech
2011-01-01
We study a pair of nonlinearly coupled identical chaotic sine square maps.More specifically,we investigate the chaos suppression associated with the variation of two parameters.Two-dimensional parameter-space regions where the chaotic dynamics of the individual chaotic sine square map is driven towards regular dynamics are delimited.Additionally,the dynamics of the coupled system is numerically characterized as the parameters are changed.In recent years,many efforts have been devoted to chaos suppression in a nonlinear dynamics field.Iglesias et al.[1] reported a chaos suppression method through numerical truncation and rounding errors,with applications in discrete-time systems.Hénon map[2] and the Burgers map[3] were used to illustrate the method.A method of feedback impulsive chaos suppression was introduced by Osipov et al.[4]It is an algorithm of suppressing chaos in continuoustime dissipative systems with an external impulsive force,whose necessary condition is a reduction of the continuous flow to a discrete-time one-dimensional map.%We study a pair of nonlinearly coupled identical chaotic sine square maps. More specifically, we investigate the chaos suppression associated with the variation of two parameters. Two-dimensional parameter-space regions where the chaotic dynamics of the individual chaotic sine square map is driven towards regular dynamics are delimited. Additionally, the dynamics of the coupled system is numerically characterized as the parameters are changed.
The bifurcation threshold value of the chaos detection system for a weak signal
Institute of Scientific and Technical Information of China (English)
李月; 杨宝俊; 杜立志; 袁野
2003-01-01
Recently, it has become an important problem to confirm the bifurcation threshold value of a chaos detectionsystem for a weak signal in the fields of chaos detection. It is directly related to whether the results of chaos detectionare correct or not. In this paper, the discrimination system for the dynamic behaviour of a chaos detection system fora weak signal is established by using the theory of linear differential equation with periodic coefficients and computingthe Lyapunov exponents of the chaos detection system; and then, the movement state of the chaos detection system isdefined. The simulation experiments show that this method can exactly confirm the bifurcation threshold value of thechaos detection system.
The chaos avant-garde memories of the early days of chaos theory
Abraham, Ralph H
2001-01-01
This book is an authoritative and unique reference for the history of chaos theory, told by the pioneers themselves. It also provides an excellent historical introduction to the concepts. There are eleven contributions, and six of them are published here for the first time - two by Steve Smale, three by Yoshisuke Ueda, and one each by Ralph Abraham, Edward Lorenz, Christian Mira, Floris Takens, T Y Li and James A Yorke, and Otto E Rossler. Contents: On How I Got Started in Dynamical Systems 1959-1962 (S Smale); Finding a Horseshoe on the Beaches of Rio (S Smale); Strange Attractors and the Ori
Chaos in the Showalter-Noyes-Bar-Eli model of the Belousov-Zhabotinskii reaction
Lindberg, David; Turner, Jack S.; Barkley, Dwight
1990-03-01
The observation of robust, large-scale chaos in the Showalter-Noyes-Bar-Eli model of the Belousov-Zhabotinskii reaction is reported. The chaos observed is comparable to that found in CSTR experiments at low flow rates.
Asynchronous Rate Chaos in Spiking Neuronal Circuits
Harish, Omri; Hansel, David
2015-01-01
The brain exhibits temporally complex patterns of activity with features similar to those of chaotic systems. Theoretical studies over the last twenty years have described various computational advantages for such regimes in neuronal systems. Nevertheless, it still remains unclear whether chaos requires specific cellular properties or network architectures, or whether it is a generic property of neuronal circuits. We investigate the dynamics of networks of excitatory-inhibitory (EI) spiking neurons with random sparse connectivity operating in the regime of balance of excitation and inhibition. Combining Dynamical Mean-Field Theory with numerical simulations, we show that chaotic, asynchronous firing rate fluctuations emerge generically for sufficiently strong synapses. Two different mechanisms can lead to these chaotic fluctuations. One mechanism relies on slow I-I inhibition which gives rise to slow subthreshold voltage and rate fluctuations. The decorrelation time of these fluctuations is proportional to the time constant of the inhibition. The second mechanism relies on the recurrent E-I-E feedback loop. It requires slow excitation but the inhibition can be fast. In the corresponding dynamical regime all neurons exhibit rate fluctuations on the time scale of the excitation. Another feature of this regime is that the population-averaged firing rate is substantially smaller in the excitatory population than in the inhibitory population. This is not necessarily the case in the I-I mechanism. Finally, we discuss the neurophysiological and computational significance of our results. PMID:26230679
Attractors, bifurcations, & chaos nonlinear phenomena in economics
Puu, Tönu
2003-01-01
The present book relies on various editions of my earlier book "Nonlinear Economic Dynamics", first published in 1989 in the Springer series "Lecture Notes in Economics and Mathematical Systems", and republished in three more, successively revised and expanded editions, as a Springer monograph, in 1991, 1993, and 1997, and in a Russian translation as "Nelineynaia Economicheskaia Dinamica". The first three editions were focused on applications. The last was differ ent, as it also included some chapters with mathematical background mate rial -ordinary differential equations and iterated maps -so as to make the book self-contained and suitable as a textbook for economics students of dynamical systems. To the same pedagogical purpose, the number of illus trations were expanded. The book published in 2000, with the title "A ttractors, Bifurcations, and Chaos -Nonlinear Phenomena in Economics", was so much changed, that the author felt it reasonable to give it a new title. There were two new math ematics ch...
Chaos Synchronization in Navier-Stokes Turbulence
Lalescu, Cristian; Meneveau, Charles; Eyink, Gregory
2013-03-01
Chaos synchronization (CS) has been studied for some time now (Pecora & Carroll 1990), for systems with only a few degrees of freedom as well as for systems described by partial differential equations (Boccaletti et al 2002). CS in general is said to be present in coupled dynamical systems when a specific property of each system has the same time evolution for all, even though the evolution itself is chaotic. The Navier-Stokes (NS) equations describe the velocity for a wide range of fluids, and their solutions are usually called turbulent if fluctuation amplitudes decrease as a power of their wavenumber. There have been some studies of CS for continuous systems (Kocarev et al 1997), but CS for NS turbulence seems not to have been investigated so far. We focus on the synchronization of the small scales of a turbulent flow for which the time history of large scales is prescribed. Our DNS results show that high-wavenumbers in turbulence are fully slaved to modes with wavenumbers up to a critical fraction of the Kolmogorov dissipation wavenumber. The motivation for our work is to study deeply sub-Kolmogorov scales in fully developed turbulence (Schumacher 2007), which we found to be recoverable even at very high Reynolds number from simulations with moderate resolutions. This work is supported by the National Science Foundation's CDI-II program, project CMMI-0941530
Muthuswamy, Bharathwaj
2015-01-01
The purpose of this introductory book is to couple the teaching of chaotic circuit and systems theory with the use of field programmable gate arrays (FPGAs). As such, it differs from other texts on chaos: first, it puts emphasis on combining theoretical methods, simulation tools and physical realization to help the reader gain an intuitive understanding of the properties of chaotic systems. Second, the "medium" used for physical realization is the FPGA. These devices are massively parallel architectures that can be configured to realize a variety of logic functions. Hence, FPGAs can be configured to emulate systems of differential equations. Nevertheless maximizing the capabilities of an FPGA requires the user to understand the underlying hardware and also FPGA design software. This is achieved by the third distinctive feature of this book: a lab component in each chapter. Here, readers are asked to experiment with computer simulations and FPGA designs, to further their understanding of con...
Disentangling Complexity from Randomness and Chaos
Directory of Open Access Journals (Sweden)
Lena C. Zuchowski
2012-02-01
Full Text Available This study aims to disentangle complexity from randomness and chaos, and to present a definition of complexity that emphasizes its epistemically distinct qualities. I will review existing attempts at defining complexity and argue that these suffer from two major faults: a tendency to neglect the underlying dynamics and to focus exclusively on the phenomenology of complex systems; and linguistic imprecisions in describing these phenomenologies. I will argue that the tendency to discuss phenomenology removed from the underlying dynamics is the main root of the difficulties in distinguishing complex from chaotic or random systems. In my own definition, I will explicitly try to avoid these pitfalls. The theoretical contemplations in this paper will be tested on a sample of five models: the random Kac ring, the chaotic CA30, the regular CA90, the complex CA110 and the complex Bak-Sneppen model. Although these modelling studies are restricted in scope and can only be seen as preliminary, they still constitute on of the first attempts to investigate complex systems comparatively.
Genotoxicity of drinking water from Chao Lake
Energy Technology Data Exchange (ETDEWEB)
Liu, Q.; Jiao, Q.C. [Nanjing Univ. (China). Dept. of Biological Science and Technology; Huang, X.M.; Jiang, J.P.; Cui, S.Q.; Yao, G.H.; Jiang, Z.R.; Zhao, H.K.; Wang, N.Y. [Anhui Antiepidemic Station, Hefei (China)
1999-02-01
Genotoxic activity appears to originate primarily from reactions of chlorine with humic substances in the source waters. Comparisons of extracts of settled versus chlorinated water have confirmed that chlorinating during water treatment produces mutagenic activity in the mutagenicity tests. Present work on XAD-2 extracts of raw, chlorinated (treated), and settled water from the Chao Lake region of China has involved a battery of mutagenicity assays for various genetic endpoints: the Salmonella test, the sister-chromatid exchange (SCE) induction in Chinese hamster lung (CHL) cells, and the micronucleus (MN) induction in the peripheral blood erythrocytes of silver carp. Extracts of raw and treated water but not the settled water are mutagenic in the Salmonella assay. On the other hand, extracts of three water samples show activity in the SCE and MN assays, especially the raw and treated water. These data show that contamination and chlorinating contribute mutagens to drinking water and suggest that the mammalian assays may be more sensitive for detecting mutagenicity in aquatic environment than the Salmonella test.
Nonadiabatic quantum chaos in atom optics
Prants, S V
2012-01-01
Coherent dynamics of atomic matter waves in a standing-wave laser field is studied. In the dressed-state picture, wave packets of ballistic two-level atoms propagate simultaneously in two optical potentials. The probability to make a transition from one potential to another one is maximal when centroids of wave packets cross the field nodes and is given by a simple formula with the single exponent, the Landau--Zener parameter $\\kappa$. If $\\kappa \\gg 1$, the motion is essentially adiabatic. If $\\kappa \\ll 1$, it is (almost) resonant and periodic. If $\\kappa \\simeq 1$, atom makes nonadiabatic transitions with a splitting of its wave packet at each node and strong complexification of the wave function as compared to the two other cases. This effect is referred as nonadiabatic quantum chaos. Proliferation of wave packets at $\\kappa \\simeq 1$ is shown to be connected closely with chaotic center-of-mass motion in the semiclassical theory of point-like atoms with positive values of the maximal Lyapunov exponent. Th...
ICT Capstone projects: The edge of chaos
Directory of Open Access Journals (Sweden)
Sue Chard
Full Text Available Capstone project processes and assessment methodologies continue to be problematic. Experience has led us to review our assessment rubrics and methods with every iteration in an attempt to refine and improve the practice and outcomes. This review has surveyed a broad range of capstone projects describing approaches to practice, assessment and sizing. In their widest sense capstone projects are described as being ambiguous and complex, tantamount, as the title of this paper implies, to artfully practising as if one is \\'on the edge of chaos.\\' There have been promising taxonomies mooted or developed to give insight into evidence of the skills, practice, knowledge and understanding associated with capstone projects. There appears to be, however, a dilemma in terms of creating a succinct vision that might inform the sizing and assessment of projects and enable us to capture its ephemeral nature. Complexity theory appears to go some way towards unpacking relevant factors which could inform the development of tools for assessment and sizing of projects. There are professional heuristics employed in the sizing of projects and standards for the assessment of capstone projects. From this review it can be seen that a fluid but accurate methodology should be developed which addresses the dilemma in such a way as to provide robust conceptual, pedagogical and sociological sizing and assessment practices.
Kinematic dynamo, supersymmetry breaking, and chaos
Ovchinnikov, Igor V.; Enßlin, Torsten A.
2016-04-01
The kinematic dynamo (KD) describes the growth of magnetic fields generated by the flow of a conducting medium in the limit of vanishing backaction of the fields onto the flow. The KD is therefore an important model system for understanding astrophysical magnetism. Here, the mathematical correspondence between the KD and a specific stochastic differential equation (SDE) viewed from the perspective of the supersymmetric theory of stochastics (STS) is discussed. The STS is a novel, approximation-free framework to investigate SDEs. The correspondence reported here permits insights from the STS to be applied to the theory of KD and vice versa. It was previously known that the fast KD in the idealistic limit of no magnetic diffusion requires chaotic flows. The KD-STS correspondence shows that this is also true for the diffusive KD. From the STS perspective, the KD possesses a topological supersymmetry, and the dynamo effect can be viewed as its spontaneous breakdown. This supersymmetry breaking can be regarded as the stochastic generalization of the concept of dynamical chaos. As this supersymmetry breaking happens in both the diffusive and the nondiffusive cases, the necessity of the underlying SDE being chaotic is given in either case. The observed exponentially growing and oscillating KD modes prove physically that dynamical spectra of the STS evolution operator that break the topological supersymmetry exist with both real and complex ground state eigenvalues. Finally, we comment on the nonexistence of dynamos for scalar quantities.
Implementation of LT codes based on chaos
Institute of Scientific and Technical Information of China (English)
Zhou Qian; Li Liang; Chen Zeng-Qiang; Zhao Jia-Xiang
2008-01-01
Fountain codes provide an efficient way to transfer information over erasure channels like the Internet.LT codes are the first codes fully realizing the digital fountain concept.They are asymptotically optimal rateless erasure codes with highly efficient encoding and decoding algorithms.In theory,for each encoding symbol of LT codes,its degree is randomly chosen according to a predetermined degree distribution,and its neighbours used to generate that encoding symbol are chosen uniformly at random.Practical implementation of LT codes usually realizes the randomness through pseudo-randomness number generator like linear congruential method.This paper applies the pseudo-randomness of chaotic sequence in the implementation of LT codes.Two Kent chaotic maps are used to determine the degree and neighbour(s)of each encoding symbol.It is shown that the implemented LT codes based on chaos perform better than the LT codes implemented by the traditional pseudo-randomness number generator.
Stability Analysis of Nonlinear Feedback Control Methods for Beam Halo-chaos
Institute of Scientific and Technical Information of China (English)
WANGZhong-sheng; FANGJin-qing; CHENGuan-rong
2003-01-01
Control of beam halo-chaos has been a more challenge subject in recent years, in which nonlinear feedback method for beam halo-chaos has been developed for control of beam halo-chaos in high-current proton linear accelerators. However, stability analysis of nonlinear feedback control methods for beam halo-chaos has still been an open and important topic in this field. In this letter.
Controlling Chaos Probability of a Bose-Einstein Condensate in a Weak Optical Superlattice
Institute of Scientific and Technical Information of China (English)
XU Jun; LUO Xiao-Bing
2009-01-01
@@ The spatial chaos probability of a Bose-Einstein condensate perturbed by a weak optical superlattice is studied. It is demonstrated that the spatial chaotic solution appears with a certain probability in a given parameter region under a random boundary condition. The effects of the lattice depths and wave vectors on the chaos probability are illustrated, and different regions associated with different chaos probabilities are found. This suggests a feasible scheme for suppressing and strengthening chaos by adjusting the optical superlattice experimentally.
Experimental study of chaos synchronization in the Belousov-Zhabotinsky chemical system
International Nuclear Information System (INIS)
Employing self-adaptive parameter regulation scheme, chaos synchronization in the Belousov-Zhabotinsky-CSTR chemical system has been studied experimentally. By optimizing the combination of regulation parameters, the trend of chaos synchronization is observed and the prediction of chaos synchronization from numerical simulation is thus verified by the experiment. In addition, the difference of sensitivity to noise with the mass coupling scheme and the self-adaptive parameter regulation scheme in chaos synchronization has also been discussed
Quantum signatures of chaos in a kicked top.
Chaudhury, S; Smith, A; Anderson, B E; Ghose, S; Jessen, P S
2009-10-01
Chaotic behaviour is ubiquitous and plays an important part in most fields of science. In classical physics, chaos is characterized by hypersensitivity of the time evolution of a system to initial conditions. Quantum mechanics does not permit a similar definition owing in part to the uncertainty principle, and in part to the Schrödinger equation, which preserves the overlap between quantum states. This fundamental disconnect poses a challenge to quantum-classical correspondence, and has motivated a long-standing search for quantum signatures of classical chaos. Here we present the experimental realization of a common paradigm for quantum chaos-the quantum kicked top- and the observation directly in quantum phase space of dynamics that have a chaotic classical counterpart. Our system is based on the combined electronic and nuclear spin of a single atom and is therefore deep in the quantum regime; nevertheless, we find good correspondence between the quantum dynamics and classical phase space structures. Because chaos is inherently a dynamical phenomenon, special significance attaches to dynamical signatures such as sensitivity to perturbation or the generation of entropy and entanglement, for which only indirect evidence has been available. We observe clear differences in the sensitivity to perturbation in chaotic versus regular, non-chaotic regimes, and present experimental evidence for dynamical entanglement as a signature of chaos. PMID:19812668
Intrinsic Motivation in Physical Education
Davies, Benjamin; Nambiar, Nathan; Hemphill, Caroline; Devietti, Elizabeth; Massengale, Alexandra; McCredie, Patrick
2015-01-01
This article describes ways in which educators can use Harter's perceived competence motivation theory, the achievement goal theory, and self-determination theory to develop students' intrinsic motivation to maintain physical fitness, as demonstrated by the Sound Body Sound Mind curriculum and proven effective by the 2013 University of…
When chaos meets hyperchaos: 4D Rössler model
Energy Technology Data Exchange (ETDEWEB)
Barrio, Roberto, E-mail: rbarrio@unizar.es [Departamento de Matemática Aplicada and IUMA, University of Zaragoza, E-50009 Zaragoza (Spain); Computational Dynamics group, University of Zaragoza, E-50009 Zaragoza (Spain); Angeles Martínez, M., E-mail: gelimc@unizar.es [Computational Dynamics group, University of Zaragoza, E-50009 Zaragoza (Spain); Serrano, Sergio, E-mail: sserrano@unizar.es [Departamento de Matemática Aplicada and IUMA, University of Zaragoza, E-50009 Zaragoza (Spain); Computational Dynamics group, University of Zaragoza, E-50009 Zaragoza (Spain); Wilczak, Daniel, E-mail: wilczak@ii.uj.edu.pl [Faculty of Mathematics and Computer Science, Jagiellonian University, Łojasiewicza 6, 30-348 Kraków (Poland)
2015-10-09
Chaotic behavior is a common feature of nonlinear dynamics, as well as hyperchaos in high-dimensional systems. In numerical simulations of these systems it is quite difficult to distinguish one from another behavior in some situations, as the results are frequently quite “noisy”. We show that in such systems a global hyperchaotic invariant set is present giving rise to long hyperchaotic transient behaviors. This fact provides a mechanism for these noisy results. The coexistence of chaos and hyperchaos is proved via Computer-Assisted Proofs techniques. - Highlights: • The coexistence of chaos and hyperchaos in the 4D Rössler system is proved via Computer-Assisted Proofs techniques. • A global hyperchaotic invariant set is present giving rise to long hyperchaotic transient behaviors. • The long transient behaviors make difficult in numerical simulations to distinguish chaos from hyperchaos in some situations.
A novel image encryption scheme based on spatial chaos map
Energy Technology Data Exchange (ETDEWEB)
Sun Fuyan [College of Control Science and Engineering, Shandong University, Jinan 250061 (China)], E-mail: fuyan.sun@gmail.com; Liu Shutang [College of Control Science and Engineering, Shandong University, Jinan 250061 (China); Li Zhongqin [HeiLongJiang Institute of Science and Technology, Harbin 150027 (China); Lue Zongwang [Information and Communication College, Guilin University of Electronic and Technology, Guilin 541004 (China); Corporate Engineering Department, Johnson Electric Co. Ltd., Shenzhen 518125 (China)
2008-11-15
In recent years, the chaos-based cryptographic algorithms have suggested some new and efficient ways to develop secure image encryption techniques, but the drawbacks of small key space and weak security in one-dimensional chaotic cryptosystems are obvious. In this paper, spatial chaos system are used for high degree security image encryption while its speed is acceptable. The proposed algorithm is described in detail. The basic idea is to encrypt the image in space with spatial chaos map pixel by pixel, and then the pixels are confused in multiple directions of space. Using this method one cycle, the image becomes indistinguishable in space due to inherent properties of spatial chaotic systems. Several experimental results, key sensitivity tests, key space analysis, and statistical analysis show that the approach for image cryptosystems provides an efficient and secure way for real time image encryption and transmission from the cryptographic viewpoint.
Polymer additives in fluid turbulence and distributed chaos
Bershadskii, A
2016-01-01
The fluids and polymers have different fundamental symmetries. Namely, the Lagrangian relabeling symmetry of fluids is absent for polymers (while the translational and rotational symmetries are still present). This fact results in spontaneous breaking of the relabeling symmetry in fluid turbulence even at a tiny polymer addition. Since helicity conservation in inviscid fluid motions is a consequence of the relabeling symmetry (due to the Noether's theorem) violation of this conservation by the polymer additives results in the strong effects in the distributed chaos. The distributed chaos in turbulence with the spontaneously broken relabeling symmetry is characterized by stretched exponential spectra $\\propto \\exp(-k/k_{\\beta})^{\\beta}$ with $\\beta =2/5$. The spectral range of this distributed chaos is extended in direction of the small wavenumbers and $k_{\\beta}$ becomes much larger in comparison with the pure fluid (Newtonian) case. This results in substantial suppression of small-scale turbulence and large-...
When chaos meets hyperchaos: 4D Rössler model
International Nuclear Information System (INIS)
Chaotic behavior is a common feature of nonlinear dynamics, as well as hyperchaos in high-dimensional systems. In numerical simulations of these systems it is quite difficult to distinguish one from another behavior in some situations, as the results are frequently quite “noisy”. We show that in such systems a global hyperchaotic invariant set is present giving rise to long hyperchaotic transient behaviors. This fact provides a mechanism for these noisy results. The coexistence of chaos and hyperchaos is proved via Computer-Assisted Proofs techniques. - Highlights: • The coexistence of chaos and hyperchaos in the 4D Rössler system is proved via Computer-Assisted Proofs techniques. • A global hyperchaotic invariant set is present giving rise to long hyperchaotic transient behaviors. • The long transient behaviors make difficult in numerical simulations to distinguish chaos from hyperchaos in some situations
Applications of chaos and nonlinear dynamics in science and engineering
Rondoni, Lamberto; Mitra, Mala
Chaos and nonlinear dynamics initially developed as a new emergent field with its foundation in physics and applied mathematics. The highly generic, interdisciplinary quality of the insights gained in the last few decades has spawned myriad applications in almost all branches of science and technology—and even well beyond. Wherever the quantitative modeling and analysis of complex, nonlinear phenomena are required, chaos theory and its methods can play a key role. This second volume concentrates on reviewing further relevant, contemporary applications of chaotic nonlinear systems as they apply to the various cutting-edge branches of engineering. This encompasses, but is not limited to, topics such as the spread of epidemics; electronic circuits; chaos control in mechanical devices; secure communication; and digital watermarking. Featuring contributions from active and leading research groups, this collection is ideal both as a reference work and as a ‘recipe book’ full of tried and tested, successf...
Color image authentication based on spatiotemporal chaos and SVD
Energy Technology Data Exchange (ETDEWEB)
Peng Zhenni [College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)], E-mail: jennyp8201@yahoo.com.cn; Liu Wenbo [College of Automation Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)], E-mail: wenboliu@nuaa.edu.cn
2008-05-15
In this paper, a new semi-fragile watermarking scheme for color image authentication is proposed based on spatiotemporal chaos and SVD (singular value decomposition). Wavelet transform is applied to watermarking. In contrast to conventional approaches where the watermark is embedded directly on the wavelet coefficients, we embed the watermark onto the SVs (singular values) of the blocks within wavelet subband. In order to enhance the security, spatiotemporal chaos is employed to select the embedding positions for each watermark bit as well as for watermark encryption. The experiment results show that the proposed scheme is able to identify malicious attacks to the image, while is robust to JPEG compression. And due to the sensitivity to the initial conditions of the spatiotemporal chaos, the security of the scheme is greatly improved.
A novel image encryption scheme based on spatial chaos map
International Nuclear Information System (INIS)
In recent years, the chaos-based cryptographic algorithms have suggested some new and efficient ways to develop secure image encryption techniques, but the drawbacks of small key space and weak security in one-dimensional chaotic cryptosystems are obvious. In this paper, spatial chaos system are used for high degree security image encryption while its speed is acceptable. The proposed algorithm is described in detail. The basic idea is to encrypt the image in space with spatial chaos map pixel by pixel, and then the pixels are confused in multiple directions of space. Using this method one cycle, the image becomes indistinguishable in space due to inherent properties of spatial chaotic systems. Several experimental results, key sensitivity tests, key space analysis, and statistical analysis show that the approach for image cryptosystems provides an efficient and secure way for real time image encryption and transmission from the cryptographic viewpoint
Dynamical topology and statistical properties of spatiotemporal chaos.
Zhuang, Quntao; Gao, Xun; Ouyang, Qi; Wang, Hongli
2012-12-01
For spatiotemporal chaos described by partial differential equations, there are generally locations where the dynamical variable achieves its local extremum or where the time partial derivative of the variable vanishes instantaneously. To a large extent, the location and movement of these topologically special points determine the qualitative structure of the disordered states. We analyze numerically statistical properties of the topologically special points in one-dimensional spatiotemporal chaos. The probability distribution functions for the number of point, the lifespan, and the distance covered during their lifetime are obtained from numerical simulations. Mathematically, we establish a probabilistic model to describe the dynamics of these topologically special points. In spite of the different definitions in different spatiotemporal chaos, the dynamics of these special points can be described in a uniform approach.
Color image authentication based on spatiotemporal chaos and SVD
International Nuclear Information System (INIS)
In this paper, a new semi-fragile watermarking scheme for color image authentication is proposed based on spatiotemporal chaos and SVD (singular value decomposition). Wavelet transform is applied to watermarking. In contrast to conventional approaches where the watermark is embedded directly on the wavelet coefficients, we embed the watermark onto the SVs (singular values) of the blocks within wavelet subband. In order to enhance the security, spatiotemporal chaos is employed to select the embedding positions for each watermark bit as well as for watermark encryption. The experiment results show that the proposed scheme is able to identify malicious attacks to the image, while is robust to JPEG compression. And due to the sensitivity to the initial conditions of the spatiotemporal chaos, the security of the scheme is greatly improved
A NOVEL APPROACH TO GENERATE FRACTAL IMAGES USING CHAOS THEORY
Directory of Open Access Journals (Sweden)
K. Thamizhchelvy
2014-08-01
Full Text Available We propose the fractal generation method to generate the different types of fractals using chaos theory. The fractals are generated by Iterated Function System (IFS technique. The chaos theory is an unpredictable behavior arises in the dynamical system. Chaos in turns explains the nonlinearity and randomness. Chaotic behavior depends upon the initial condition called as “seed” or “key”. Pseudo Random Number Generator (PRNG fixes the initial condition from the difference equations. The system uses the PRNG value and it generates the fractals, also it is hard to break. We apply the rules to generate the fractals. The different types of fractals are generated for the same data, because of the great sensitivity to the initial condition. It can be used as a digital signature in online applications such as e-Banking and online shopping.
Multistability, chaos, and random signal generation in semiconductor superlattices
Ying, Lei; Huang, Danhong; Lai, Ying-Cheng
2016-06-01
Historically, semiconductor superlattices, artificial periodic structures of different semiconductor materials, were invented with the purpose of engineering or manipulating the electronic properties of semiconductor devices. A key application lies in generating radiation sources, amplifiers, and detectors in the "unusual" spectral range of subterahertz and terahertz (0.1-10 THz), which cannot be readily realized using conventional radiation sources, the so-called THz gap. Efforts in the past three decades have demonstrated various nonlinear dynamical behaviors including chaos, suggesting the potential to exploit chaos in semiconductor superlattices as random signal sources (e.g., random number generators) in the THz frequency range. We consider a realistic model of hot electrons in semiconductor superlattice, taking into account the induced space charge field. Through a systematic exploration of the phase space we find that, when the system is subject to an external electrical driving of a single frequency, chaos is typically associated with the occurrence of multistability. That is, for a given parameter setting, while there are initial conditions that lead to chaotic trajectories, simultaneously there are other initial conditions that lead to regular motions. Transition to multistability, i.e., the emergence of multistability with chaos as a system parameter passes through a critical point, is found and argued to be abrupt. Multistability thus presents an obstacle to utilizing the superlattice system as a reliable and robust random signal source. However, we demonstrate that, when an additional driving field of incommensurate frequency is applied, multistability can be eliminated, with chaos representing the only possible asymptotic behavior of the system. In such a case, a random initial condition will lead to a trajectory landing in a chaotic attractor with probability 1, making quasiperiodically driven semiconductor superlattices potentially as a reliable
Multistability, chaos, and random signal generation in semiconductor superlattices.
Ying, Lei; Huang, Danhong; Lai, Ying-Cheng
2016-06-01
Historically, semiconductor superlattices, artificial periodic structures of different semiconductor materials, were invented with the purpose of engineering or manipulating the electronic properties of semiconductor devices. A key application lies in generating radiation sources, amplifiers, and detectors in the "unusual" spectral range of subterahertz and terahertz (0.1-10 THz), which cannot be readily realized using conventional radiation sources, the so-called THz gap. Efforts in the past three decades have demonstrated various nonlinear dynamical behaviors including chaos, suggesting the potential to exploit chaos in semiconductor superlattices as random signal sources (e.g., random number generators) in the THz frequency range. We consider a realistic model of hot electrons in semiconductor superlattice, taking into account the induced space charge field. Through a systematic exploration of the phase space we find that, when the system is subject to an external electrical driving of a single frequency, chaos is typically associated with the occurrence of multistability. That is, for a given parameter setting, while there are initial conditions that lead to chaotic trajectories, simultaneously there are other initial conditions that lead to regular motions. Transition to multistability, i.e., the emergence of multistability with chaos as a system parameter passes through a critical point, is found and argued to be abrupt. Multistability thus presents an obstacle to utilizing the superlattice system as a reliable and robust random signal source. However, we demonstrate that, when an additional driving field of incommensurate frequency is applied, multistability can be eliminated, with chaos representing the only possible asymptotic behavior of the system. In such a case, a random initial condition will lead to a trajectory landing in a chaotic attractor with probability 1, making quasiperiodically driven semiconductor superlattices potentially as a reliable
Predicting vibration signals of automobile engine using chaos theory
Institute of Scientific and Technical Information of China (English)
LIU Chun; ZHANG Laibin; WANG Zhaohui
2004-01-01
Condition monitoring and life prediction of the vehicle engine is an important and urgent problem during the vehicle development process. The vibration signals that are closely associated with the engine running condition and its development trend are complex and nonlinear. The chaos theory is used to treat the nonlinear dynamical system recently. A novel chaos method in conjunction with SVD (singular value decomposition)denoising skill are used to predict the vibration time series. Two types of time series and their prediction errors are provided to illustrate the practical utility of the method.
Application of chaos and fractals to computer vision
Farmer, Michael E
2014-01-01
This book provides a thorough investigation of the application of chaos theory and fractal analysis to computer vision. The field of chaos theory has been studied in dynamical physical systems, and has been very successful in providing computational models for very complex problems ranging from weather systems to neural pathway signal propagation. Computer vision researchers have derived motivation for their algorithms from biology and physics for many years as witnessed by the optical flow algorithm, the oscillator model underlying graphical cuts and of course neural networks. These algorithm
In the Wake of Chaos Unpredictable Order in Dynamical Systems
Kellert, Stephen H
1993-01-01
Chaos theory has captured scientific and popular attention. What began as the discovery of randomness in simple physical systems has become a widespread fascination with "chaotic" models of everything from business cycles to brainwaves to heart attacks. But what exactly does this explosion of new research into chaotic phenomena mean for our understanding of the world? In this timely book, Stephen Kellert takes the first sustained look at the broad intellectual and philosophical questions raised by recent advances in chaos theory—its implications for science as a source of knowledge a
The edge of chaos: A nonlinear view of psychoanalytic technique.
Galatzer-Levy, Robert M
2016-04-01
The field of nonlinear dynamics (or chaos theory) provides ways to expand concepts of psychoanalytic process that have implications for the technique of psychoanalysis. This paper describes how concepts of "the edge of chaos," emergence, attractors, and coupled oscillators can help shape analytic technique resulting in an approach to doing analysis which is at the same time freer and more firmly based in an enlarged understanding of the ways in which psychoanalysis works than some current recommendation about technique. Illustrations from a lengthy analysis of an analysand with obsessive-compulsive disorder show this approach in action. PMID:27030426
Quantum dissipative chaos in the statistics of excitation numbers
Kryuchkyan, G Y; Kryuchkyan, Gagik Yu.; Manvelyan, Suren B.
2002-01-01
A quantum manifestation of chaotic classical dynamics is found in the framework of oscillatory numbers statistics for the model of nonlinear dissipative oscillator. It is shown by numerical simulation of an ensemble of quantum trajectories that the probability distributions and variances of oscillatory number states are strongly transformed in the order-to-chaos transition. The nonclassical, sub-Poissonian statistics of oscillatory excitation numbers is established for chaotic dissipative dynamics in the framework of Fano factor and Wigner functions. These results are proposed for testing and experimental studing of quantum dissipative chaos.
Dynamic Ice-Water Interactions Form Europa's Chaos Terrains
Blankenship, D. D.; Schmidt, B. E.; Patterson, G. W.; Schenk, P.
2011-12-01
Unique to the surface of Europa, chaos terrain is diagnostic of the properties and dynamics of its icy shell. We present a new model that suggests large melt lenses form within the shell and that water-ice interactions above and within these lenses drive the production of chaos. This model is consistent with key observations of chaos, predicts observables for future missions, and indicates that the surface is likely still active today[1]. We apply lessons from ice-water interaction in the terrestrial cryosphere to hypothesize a dynamic lense-collapse model to for Europa's chaos terrain. Chaos terrain morphology, like that of Conamara chaos and Thera Macula, suggests a four-phase formation [1]: 1) Surface deflection occurs as ice melts over ascending thermal plumes, as regularly occurs on Earth as subglacial volcanoes activate. The same process can occur at Europa if thermal plumes cause pressure melt as they cross ice-impurity eutectics. 2) Resulting hydraulic gradients and driving forces produce a sealed, pressurized melt lense, akin to the hydraulic sealing of subglacial caldera lakes. On Europa, the water cannot escape the lense due to the horizontally continuous ice shell. 3) Extension of the brittle ice lid above the lense opens cracks, allowing for the ice to be hydrofractured by pressurized water. Fracture, brine injection and percolation within the ice and possible iceberg toppling produces ice-melange-like granular matrix material. 4) Refreezing of the melt lense and brine-filled pores and cracks within the matrix results in raised chaos. Brine soaking and injection concentrates the ice in brines and adds water volume to the shell. As this englacial water freezes, the now water-filled ice will expand, not unlike the process of forming pingos and other "expansion ice" phenomena on Earth. The refreezing can raise the surface and create the oft-observed matrix "domes" In this presentation, we describe how catastrophic ice-water interactions on Earth have
MPPT of PV array using stepped-up chaos optimization algorithm
Wang, Lihua; WEI, XUEYE; SHAO, YUQIN; ZHU, TIANLONG; ZHANG, JUNHONG
2015-01-01
In order to achieve maximum efficiency, a maximum power point tracking (MPPT) scheme should be applied in photovoltaic systems. Among all the MPPT schemes, the chaos optimization scheme is one of the hot topics in recent years. In this study, a novel stepped-up chaos optimization algorithm is presented. A chaos mapping $x_{n+1} =\\mu \\sin (\\pi x_{n} )$ is used as a chaos generator to produce a chaos variable. In the process of MPPT, a coarse search is done to find the current optimal solution ...
Protein intrinsic disorder in plants
Florencio ePazos; Natalia ePietrosemoli; García-Martín, Juan A.; Roberto eSolano
2013-01-01
To some extent contradicting the classical paradigm of the relationship between protein 3D structure and function, now it is clear that large portions of the proteomes, especially in higher organisms, lack a fixed structure and still perform very important functions. Proteins completely or partially unstructured in their native (functional) form are involved in key cellular processes underlain by complex networks of protein interactions. The intrinsic conformational flexibility of these disor...
Quasar redshifts: the intrinsic component
Hansen, Peter M.
2016-09-01
The large observed redshift of quasars has suggested large cosmological distances and a corresponding enormous energy output to explain the brightness or luminosity as seen at earth. Alternative or complementary sources of redshift have not been identified by the astronomical community. This study examines one possible source of additional redshift: an intrinsic component based on the plasma characteristics of high temperature and high electron density which are believed to be present.
Decoherence: Intrinsic, Extrinsic, and Environmental
Stamp, Philip
2012-02-01
Environmental decoherence times have been difficult to predict in solid-state systems. In spin systems, environmental decoherence is predicted to arise from nuclear spins, spin-phonon interactions, and long-range dipolar interactions [1]. Recent experiments have confirmed these predictions quantitatively in crystals of Fe8 molecules [2]. Coherent spin dynamics was observed over macroscopic volumes, with a decoherence Q-factor Qφ= 1.5 x10^6 (the upper predicted limit in this system being Qφ= 6 x10^7). Decoherence from dipolar interactions is particularly complex, and depends on the shape and the quantum state of the system. No extrinsic ``noise'' decoherence was observed. The generalization to quantum dot and superconducting qubit systems is also discussed. We then discuss searches for ``intrinsic'' decoherence [3,4], coming from non-linear corrections to quantum mechanics. Particular attention is paid to condensed matter tests of such intrinsic decoherence, in hybrid spin/optomechanical systems, and to ways of distinguishing intrinsic decoherence from environmental and extrinsic decoherence sources. [4pt] [1] Morello, A. Stamp, P. C. E. & Tupitsyn, Phys. Rev. Lett. 97, 207206 (2006).[0pt] [2] S. Takahashi et al., Nature 476, 76 (2011).[0pt] [3] Stamp, P. C. E., Stud. Hist. Phil. Mod. Phys. 37, 467 (2006). [0pt] [4] Stamp, P.C.E., Phil. Trans. Roy. Soc. A (to be published)
Experimental observation of a chaos-to-chaos transition in laser droplet generation
Krese, Blaz; Govekar, Edvard
2010-01-01
We examine the dynamics of laser droplet generation in dependence on the detachment pulse power. In the absence of the detachment pulse, undulating pendant droplets are formed at the end of a properly fed metal wire due to the impact of the primary laser pulse that induces melting. Eventually, these droplets detach, i.e. overcome the surface tension, because of their increasing mass. We show that this spontaneous dripping is deterministically chaotic by means of a positive largest Lyapunov exponent and a negative divergence. In the presence of the detachment pulse, however, the generation of droplets is fastened depending on the pulse power. At high powers, the spontaneity of dripping is completely overshadowed by the impact of the detachment pulse. Still, amplitude chaos can be detected, which similarly as the spontaneous dripping, is characterized by a positive largest Lyapunov exponent and a negative divergence, thus indicating that the observed dynamics is deterministically chaotic with an attractor as so...
Institute of Scientific and Technical Information of China (English)
FANG Jin-Qing; YU Xing-Huo
2004-01-01
@@ Study of beam halo-chaos has become a key issue of concern for many future important applications. Control of halo-chaos has been researched intensively. This is the first time that the synchronization of beam halo-chaos has been realized in this field so far. Two nonlinear feedback control methods are proposed for the cascading synchronizing halo-chaos in coupled lattices of a periodic focusing channel. The simulation results show that the methods are effective. The realization of the synchronization of beam halo-chaos is significant not only for halo-chaos control itself but also for halo-chaos-based secure communication which may become an innovative technique.
The bifurcation threshold value of the chaos detection system for a weak signal
Institute of Scientific and Technical Information of China (English)
李月; 杨宝俊; 杜立志; 袁野
2003-01-01
Recently, it has become an important problem to confirm the bifurcation threshold value of a chaos detection system for a weak signal in the fields of chaos detection. It is directly related to whether the results of chaos detection are correct or not. In this paper, the discrimination system for the dynamic behaviour of a chaos detection system for a weak signal is established by using the theory of linear differential equation with periodic coefficients and computing the Lyapunov exponents of the chaos detection system; and then, the movement state of the chaos detection system is defined. The simulation experiments show that this method can exactly confirm the bifurcation threshold value of the chaos detection system.
Intrinsic Patterns of Human Activity
Hu, Kun; Ivanov, Plamen Ch.; Chen, Zhi; Hilton, Michael; Stanley, H. Eugene; Shea, Steven
2003-03-01
Activity is one of the defining features of life. Control of human activity is complex, being influenced by many factors both extrinsic and intrinsic to the body. The most obvious extrinsic factors that affect activity are the daily schedule of planned events, such as work and recreation, as well as reactions to unforeseen or random events. These extrinsic factors may account for the apparently random fluctuations in human motion observed over short time scales. The most obvious intrinsic factors are the body clocks including the circadian pacemaker that influences our sleep/wake cycle and ultradian oscillators with shorter time scales [2, 3]. These intrinsic rhythms may account for the underlying regularity in average activity level over longer periods of up to 24 h. Here we ask if the known extrinsic and intrinsic factors fully account for all complex features observed in recordings of human activity. To this end, we measure activity over two weeks from forearm motion in subjects undergoing their regular daily routine. Utilizing concepts from statistical physics, we demonstrate that during wakefulness human activity possesses previously unrecognized complex dynamic patterns. These patterns of activity are characterized by robust fractal and nonlinear dynamics including a universal probability distribution and long-range power-law correlations that are stable over a wide range of time scales (from minutes to hours). Surprisingly, we find that these dynamic patterns are unaffected by changes in the average activity level that occur within individual subjects throughout the day and on different days of the week, and between subjects. Moreover, we find that these patterns persist when the same subjects undergo time-isolation laboratory experiments designed to account for the phase of the circadian pacemaker, and control the known extrinsic factors by restricting behaviors and manipulating scheduled events including the sleep/wake cycle. We attribute these newly
vs. a polynomial chaos-based MCMC
Siripatana, Adil
2014-08-01
Bayesian Inference of Manning\\'s n coefficient in a Storm Surge Model Framework: comparison between Kalman lter and polynomial based method Adil Siripatana Conventional coastal ocean models solve the shallow water equations, which describe the conservation of mass and momentum when the horizontal length scale is much greater than the vertical length scale. In this case vertical pressure gradients in the momentum equations are nearly hydrostatic. The outputs of coastal ocean models are thus sensitive to the bottom stress terms de ned through the formulation of Manning\\'s n coefficients. This thesis considers the Bayesian inference problem of the Manning\\'s n coefficient in the context of storm surge based on the coastal ocean ADCIRC model. In the first part of the thesis, we apply an ensemble-based Kalman filter, the singular evolutive interpolated Kalman (SEIK) filter to estimate both a constant Manning\\'s n coefficient and a 2-D parameterized Manning\\'s coefficient on one ideal and one of more realistic domain using observation system simulation experiments (OSSEs). We study the sensitivity of the system to the ensemble size. we also access the benefits from using an in ation factor on the filter performance. To study the limitation of the Guassian restricted assumption on the SEIK lter, 5 we also implemented in the second part of this thesis a Markov Chain Monte Carlo (MCMC) method based on a Generalized Polynomial chaos (gPc) approach for the estimation of the 1-D and 2-D Mannning\\'s n coe cient. The gPc is used to build a surrogate model that imitate the ADCIRC model in order to make the computational cost of implementing the MCMC with the ADCIRC model reasonable. We evaluate the performance of the MCMC-gPc approach and study its robustness to di erent OSSEs scenario. we also compare its estimates with those resulting from SEIK in term of parameter estimates and full distributions. we present a full analysis of the solution of these two methods, of the
BOOK REVIEW: Chaos: A Very Short Introduction
Klages, R.
2007-07-01
This book is a new volume of a series designed to introduce the curious reader to anything from ancient Egypt and Indian philosophy to conceptual art and cosmology. Very handy in pocket size, Chaos promises an introduction to fundamental concepts of nonlinear science by using mathematics that is `no more complicated than X=2. Anyone who ever tried to give a popular science account of research knows that this is a more challenging task than writing an ordinary research article. Lenny Smith brilliantly succeeds to explain in words, in pictures and by using intuitive models the essence of mathematical dynamical systems theory and time series analysis as it applies to the modern world. In a more technical part he introduces the basic terms of nonlinear theory by means of simple mappings. He masterly embeds this analysis into the social, historical and cultural context by using numerous examples, from poems and paintings over chess and rabbits to Olbers' paradox, card games and `phynance'. Fundamental problems of the modelling of nonlinear systems like the weather, sun spots or golf balls falling through an array of nails are discussed from the point of view of mathematics, physics and statistics by touching upon philosophical issues. At variance with Laplace's demon, Smith's 21st century demon makes `real world' observations only with limited precision. This poses a severe problem to predictions derived from complex chaotic models, where small variations of initial conditions typically yield totally different outcomes. As Smith argues, this difficulty has direct implications on decision-making in everyday modern life. However, it also asks for an inherently probabilistic theory, which somewhat reminds us of what we are used to in the microworld. There is little to criticise in this nice little book except that some figures are of poor quality thus not really reflecting the beauty of fractals and other wonderful objects in this field. I feel that occasionally the book
2006-01-01
NASA's Spitzer and Hubble Space Telescopes have teamed up to expose the chaos that baby stars are creating 1,500 light-years away in a cosmic cloud called the Orion nebula. This striking infrared and visible-light composite indicates that four monstrously massive stars at the center of the cloud may be the main culprits in the familiar Orion constellation. The stars are collectively called the 'Trapezium.' Their community can be identified as the yellow smudge near the center of the image. Swirls of green in Hubble's ultraviolet and visible-light view reveal hydrogen and sulfur gas that have been heated and ionized by intense ultraviolet radiation from the Trapezium's stars. Meanwhile, Spitzer's infrared view exposes carbon-rich molecules called polycyclic aromatic hydrocarbons in the cloud. These organic molecules have been illuminated by the Trapezium's stars, and are shown in the composite as wisps of red and orange. On Earth, polycyclic aromatic hydrocarbons are found on burnt toast and in automobile exhaust. Together, the telescopes expose the stars in Orion as a rainbow of dots sprinkled throughout the image. Orange-yellow dots revealed by Spitzer are actually infant stars deeply embedded in a cocoon of dust and gas. Hubble showed less embedded stars as specks of green, and foreground stars as blue spots. Stellar winds from clusters of newborn stars scattered throughout the cloud etched all of the well-defined ridges and cavities in Orion. The large cavity near the right of the image was most likely carved by winds from the Trapezium's stars. Located 1,500 light-years away from Earth, the Orion nebula is the brightest spot in the sword of the Orion, or the 'Hunter' constellation. The cosmic cloud is also our closest massive star-formation factory, and astronomers believe it contains more than 1,000 young stars. The Orion constellation is a familiar sight in the fall and winter night sky in the northern hemisphere. The nebula is invisible to the unaided eye
Security problems with a chaos-based deniable authentication scheme
International Nuclear Information System (INIS)
Recently, a new scheme was proposed for deniable authentication. Its main originality lied on applying a chaos-based encryption-hash parallel algorithm and the semi-group property of the Chebyshev chaotic map. Although original and practicable, its insecurity and inefficiency are shown in this paper, thus rendering it inadequate for adoption in e-commerce
Review of Stephen Arons's "Short Route to Chaos."
Glenn, Charles L.
1998-01-01
"Short Route to Chaos" criticizes the Goals 2000 program, related educational reforms, and the agenda of the Religious Right from the viewpoint of the secular Left. Arons supports school choice, school and teacher independence from government regulation of instructional content, publicly funded schools, and equity in funding. (SLD)
Toward Therapeutic Autopoiesis: Chaos, Complexity, and Narrative Therapy.
Chen, Mei-whei
The paradigm of modern psychology has been the determinism of Newtonian physics. That model earns psychology status as a science yet tunnels it to a linear way of unraveling human functioning. Responding to demands for a more holistic approach to psychological practice, it is necessary to redefine the "self" and other terms. Chaos, complexity, and…
Confidential Communication Through Chaos Encryption in Wireless Sensor Network
Institute of Scientific and Technical Information of China (English)
CHEN Shuai; ZHONG Xian-xin
2007-01-01
A new byte block cipher algorithm with discrete chaos and Feistel structure has been studied for confidential communication in wireless sensor network to improve security. After permutation, the byte block was encrypted through a Feistel structure in multiple turns and afterwards replaced again. The child keys are the composite sequence of discrete chaos and linear congruence sequences. Both the plain text and cipher text are of 8 bits. The number of keys is alterable. A nonlinear encryption function in the Feistel structure with chaos was constructed. The cipher algorithm was realized in the Micaz node,and the confidential communication experiment in wireless sensor network was completed successfully. Additional ROM memory required for the cipher algorithm is 4144 bytes and an additional RAM memory 61 bytes. The cipher algorithm is nonlinear chaos and the Feistel structure holds the best of the RC6, DES and SKIPJACK cipher algorithms.The result shows that the algorithm needs a little memory and is safe at a high level.
Bifurcations, Period doubling and chaos in clarinet-like systems
Maganza, Christian; Caussé, René; Laloë, Franck
1986-01-01
Wind instruments provide interesting hydrodynamical systems where non-linearities are important but well localized. A simple analysis shows that these systems should undergo Feignebaum-type route to chaos, with a cascade of period doublings. Experiments have been performed fo confirm these predictions
Between order and chaos: The quest for meaningful information
P. Adriaans
2009-01-01
The notion of meaningful information seems to be associated with the sweet spot between order and chaos. This form of meaningfulness of information, which is primarily what science is interested in, is not captured by both Shannon information and Kolmogorov complexity. In this paper I develop a theo
Two-mode chaos and its synchronization properties
DEFF Research Database (Denmark)
Postnov, D E; Shishkin, A V; Sosnovtseva, Olga;
2005-01-01
Using a simple model with bimodal dynamics, we investigate the intra- and inter-system entrainment of the two different time scales involved in the chaotic oscillations. The transition between mode-locked and mode-unlocked chaos is analyzed for a single system. For coupled oscillators, we...
Chaos Synchronization on Parameters Adaptive Control for Chen Chaotic System
Institute of Scientific and Technical Information of China (English)
ZHOU Ping
2003-01-01
Chaos synchronization of Chen chaotic system for parameters unknown is discussed in this paper using a scalar output. Using the concept of conditional Lyapunov exponents, the negativity of all Lyapunov exponents shows the synchronization of transmitter systems with receiver systems even though system parametes are not known to receiver systems.
Suppressing Spatiotemporal Chaos via Non-feedback Pinning Method
Institute of Scientific and Technical Information of China (English)
WU Shun-Guang; SANG Hai-Bo; HE Kai-Fen
2001-01-01
The spatiotemporal chaos in the system described by a one-dimensional nonlinear drift-wave equation is suppressed by the non-feedback pinning method. By adding additive external noise to the controlled state, we find that the deviation from the target spacetime pattern increases in a power law with noise intensity. The possible controlling mechanism is discussed.
Predicting Storm Surges: Chaos, Computational Intelligence, Data Assimilation, Ensembles
Siek, M.B.L.A.
2011-01-01
Accurate predictions of storm surge are of importance in many coastal areas. This book focuses on data-driven modelling using methods of nonlinear dynamics and chaos theory for predicting storm surges. A number of new enhancements are presented: phase space dimensionality reduction, incomplete time
Chaos, patterns, coherent structures, and turbulence: Reflections on nonlinear science
Ecke, Robert E.
2015-09-01
The paradigms of nonlinear science were succinctly articulated over 25 years ago as deterministic chaos, pattern formation, coherent structures, and adaptation/evolution/learning. For chaos, the main unifying concept was universal routes to chaos in general nonlinear dynamical systems, built upon a framework of bifurcation theory. Pattern formation focused on spatially extended nonlinear systems, taking advantage of symmetry properties to develop highly quantitative amplitude equations of the Ginzburg-Landau type to describe early nonlinear phenomena in the vicinity of critical points. Solitons, mathematically precise localized nonlinear wave states, were generalized to a larger and less precise class of coherent structures such as, for example, concentrated regions of vorticity from laboratory wake flows to the Jovian Great Red Spot. The combination of these three ideas was hoped to provide the tools and concepts for the understanding and characterization of the strongly nonlinear problem of fluid turbulence. Although this early promise has been largely unfulfilled, steady progress has been made using the approaches of nonlinear science. I provide a series of examples of bifurcations and chaos, of one-dimensional and two-dimensional pattern formation, and of turbulence to illustrate both the progress and limitations of the nonlinear science approach. As experimental and computational methods continue to improve, the promise of nonlinear science to elucidate fluid turbulence continues to advance in a steady manner, indicative of the grand challenge nature of strongly nonlinear multi-scale dynamical systems.
Optimal control for stochastic systems with polynomial chaos
Gallagher, David James
Assuring robustness of control system performance against model uncertainty is a significant component of control design. Current methods for developing a robust controller, however, are typically either too conservative or too computationally expensive. This thesis uses generalized polynomial chaos alongside finite-horizon optimal control as a new method of robust control design for a stochastic system. Since the equations for the mean and variance of the response can be expressed in terms of coefficients from a polynomial chaos expansion, optimizing a polynomial chaos expansion can be used to optimize the mean and variance, thus providing robust responses in a stochastic system. This thesis first provides a review of the concepts and literature then the rationale as well as the derivation of the proposed robust control method. Three examples are given to show the effectiveness of the new control method and are discussed. In particular, the final example demonstrates the applicability of using polynomial chaos to provide robust control for a stochastic soft landing problem.
Organisational Leadership and Chaos Theory: Let's Be Careful
Galbraith, Peter
2004-01-01
This article addresses issues associated with applications of ideas from "chaos theory" to educational administration and leadership as found in the literature. Implications are considered in relation to claims concerning the behaviour of non-linear dynamic systems, and to the nature of the interpretations and recommendations that are made. To aid…
Parametric resonance induced chaos in magnetic damped driven pendulum
Khomeriki, Giorgi
2016-07-01
A damped driven pendulum with a magnetic driving force, appearing from a solenoid, where ac current flows is considered. The solenoid acts on the magnet, which is located at a free end of the pendulum. In this system the existence and interrelation of chaos and parametric resonance is theoretically examined. Derived analytical results are supported by numerical simulations and conducted experiments.
Role of nonlinear dynamics and chaos in applied sciences
International Nuclear Information System (INIS)
Nonlinear dynamics manifests itself in a number of phenomena in both laboratory and day to day dealings. However, little attention was being paid to this dynamically rich field. With the advent of high speed computers with visual graphics, the field has proliferated over past few years. One of the most rewarding realization from nonlinear dynamics is the universally acclaimed field of chaos. Chaos has brought in order and has broken the disciplinary boundaries that existed until recently. With its universal phenomena, almost all disciplines following an evolutionary character can be treated on same footing. Chaotic dynamics has its grounding in the multidisciplinary field of synergetics founded by Professor Hermann Haken. In this report, we address some of the basics related to the field of chaos. We have discussed simple mechanisms for generating chaotic trajectories, ways and means of characterizing such systems and the manifestation of their signatures in the evolutions. We have mentioned the links of this field with other existing theories. We have outlined the topics on bifurcation and stability of dynamical systems. Information theoretic aspects and notions on fractal geometry are reviewed in the light of dynamical characterization of chaotic systems. Application oriented views of this novel dynamical phenomena are discussed through examples on simple nonlinear electronic circuits and a BWR reactor. Some ideas relating to control and synchronization in chaotic systems also addressed. In conclusion, we have explored the possibilities of exploiting nonlinear dynamics and chaos in the context of multidisciplinary character of BARC. (author)
Integrability and Quantum Chaos in Spin Glass Shards
Georgeot, B.; Shepelyansky, D. L.
1998-01-01
We study spin glass clusters ("shards") in a random transverse magnetic field, and determine the regime where quantum chaos and random matrix level statistics emerge from the integrable limits of weak and strong field. Relations with quantum phase transition are also discussed.
Does the transition to chaos determine the dynamic aperture?
International Nuclear Information System (INIS)
We review the important notion of the dynamic aperture of a storage ring with emphasis on its relation to general ideas of dynamical instability, notably the transition to chaos. Practical approaches to the problem are compared. We suggest a somewhat novel quantitative guide to the old problem of choosing machine tunes based on a heuristic blend of KAM theory and resonance selection rules
Job Assignments, Intrinsic Motivation and Explicit Incentives
Nafziger, Julia
2008-01-01
This paper considers the interplay of job assignments with the intrinsic and extrinsic motivation of an agent. Job assignments influence the self confidence of the agent, and thereby his intrinsic motivation. Monetary reward allow the principal to complement intrinsic motivation with extrinsic incentives. The main result is that the principal chooses an inefficient job assignment rule to enhance the agent's intrinsic motivation even though she can motivate him with monetary rewards. This show...
The butterfly and the tornado: chaos theory and climate change
International Nuclear Information System (INIS)
In this book, the author addresses two topics: the theory of chaos, and climate change. The first chapters propose a prehistory and history of chaos, from Newton, Laplace and Lorenz and their controversies as far as prehistory of chaos is concerned, and with different works performed during the twentieth century (Hadamard, Birkhoff, van der Pol, and so on, until Lorenz, the MIT meteorologist and the discovery of the Butterfly Effect, and more recent works by Yorke and Feigenbaum about the logistic equation and the transition to chaos) as far as recent history is concerned. The next chapter describes the deterministic chaos by introducing non linear dynamic systems and distinguishing three regimes: steady, periodic or chaotic. The second part addresses climate change, outlines that global warming is a reality, that the main origin is the increase of greenhouse effect, and that CO2 emissions related to human activity are the main origin of this additional greenhouse effect. The author notably recalls the controversy about the analysis of the global average temperature curve, discusses the assessment of average temperatures from a statistical point of view and in relationship with the uneven distribution of survey stations. The last chapter discusses the numerical modelling of time and climate, and the validity of the Butterfly Effect. The author also proposes a brief overview of the IPCC, discusses the emergence of an international climate policy (UN convention, Kyoto protocol), evokes the use of game theory to ensure a convergence of treaties, and analyses the economic situation of several countries (including Spain) since the Kyoto protocol
Presymplectic structures and intrinsic Lagrangians
Grigoriev, Maxim
2016-01-01
It is well-known that a Lagrangian induces a compatible presymplectic form on the equation manifold (stationary surface, understood as a submanifold of the respective jet-space). Given an equation manifold and a compatible presymplectic form therein, we define the first-order Lagrangian system which is formulated in terms of the intrinsic geometry of the equation manifold. It has a structure of a presymplectic AKSZ sigma model for which the equation manifold, equipped with the presymplectic form and the horizontal differential, serves as the target space. For a wide class of systems (but not all) we show that if the presymplectic structure originates from a given Lagrangian, the proposed first-order Lagrangian is equivalent to the initial one and hence the Lagrangian per se can be entirely encoded in terms of the intrinsic geometry of its stationary surface. If the compatible presymplectic structure is generic, the proposed Lagrangian is only a partial one in the sense that its stationary surface contains the...
Intrinsic Alignments in the Illustris Simulation
Hilbert, Stefan; Schneider, Peter; Springel, Volker; Vogelsberger, Mark; Hernquist, Lars
2016-01-01
We study intrinsic alignments (IA) of galaxy image shapes within the Illustris cosmic structure formation simulations. We investigate how IA correlations depend on observable galaxy properties such as stellar mass, apparent magnitude, redshift, and photometric type, and on the employed shape measurement method. The correlations considered include the matter density-intrinsic ellipticity (mI), galaxy density-intrinsic ellipticity (dI), gravitational shear-intrinsic ellipticity (GI), and intrinsic ellipticity-intrinsic ellipticity (II) correlations. We find stronger correlations for more massive and more luminous galaxies, as well as for earlier photometric types, in agreement with observations. Moreover, shape measurement methods that down-weight the outer parts of galaxy images produce much weaker IA signals on intermediate and large scales than methods employing flat radial weights. Thus, the expected contribution of intrinsic alignments to the observed ellipticity correlation in tomographic cosmic shear sur...
Directory of Open Access Journals (Sweden)
Novelletto Andrea
2011-03-01
Full Text Available Abstract Background The process of Greek colonization of the central and western Mediterranean during the Archaic and Classical Eras has been understudied from the perspective of population genetics. To investigate the Y chromosomal demography of Greek colonization in the western Mediterranean, Y-chromosome data consisting of 29 YSNPs and 37 YSTRs were compared from 51 subjects from Provence, 58 subjects from Smyrna and 31 subjects whose paternal ancestry derives from Asia Minor Phokaia, the ancestral embarkation port to the 6th century BCE Greek colonies of Massalia (Marseilles and Alalie (Aleria, Corsica. Results 19% of the Phokaian and 12% of the Smyrnian representatives were derived for haplogroup E-V13, characteristic of the Greek and Balkan mainland, while 4% of the Provencal, 4.6% of East Corsican and 1.6% of West Corsican samples were derived for E-V13. An admixture analysis estimated that 17% of the Y-chromosomes of Provence may be attributed to Greek colonization. Using the following putative Neolithic Anatolian lineages: J2a-DYS445 = 6, G2a-M406 and J2a1b1-M92, the data predict a 0% Neolithic contribution to Provence from Anatolia. Estimates of colonial Greek vs. indigenous Celto-Ligurian demography predict a maximum of a 10% Greek contribution, suggesting a Greek male elite-dominant input into the Iron Age Provence population. Conclusions Given the origin of viniculture in Provence is ascribed to Massalia, these results suggest that E-V13 may trace the demographic and socio-cultural impact of Greek colonization in Mediterranean Europe, a contribution that appears to be considerably larger than that of a Neolithic pioneer colonization.
Papa, M. A.; Tardo, V.
2011-09-01
This research has analysed the distribution of ceramic finds from classical and archaic ages in the territory of the ancient Greek colony Himera, a town situated near Termini Imerese, in the province of Palermo (Sicily, Italy), which has been the site of systematic excavations carried out by the University of Palermo since the Sixties. The study of about 1500 ceramic fragments, dated back to the 6th-5th century B.C., has allowed to develop an approach to the understanding of the role played by ceramics in the relations between different societies and cultures. Besides the most common analysis factors for the ceramic manufactures, such as their production and distribution, a major factor is the way the manufactures were used. From this wider perspective, a new methodology has been developed about information potential of functional analysis. The interpretation of data about the manufacture distribution was made by means of GIS methodologies, querying the alphanumerical classification database and relating the manufacture typological data to the geo-cartographic ones by means of applying intersite-level spatial analysis. Thus, each archaeological piece of information about the finds can be analysed in relation to the territory geo-morphological features and the obtained data can be processed with specific software environments, in order to suggest reconstruction models for the anthropic landscape, based on the relation between coeval sites and distance from specific environment features — for example, distance from water sources, raw materials, road condition etc. The computer application used for data handling, presentation and analysis, becomes this way a tool of research aimed at the comprehension of settlement dynamics in the historical scenery. This study is the occasion to propose such an analysis system of cultural heritage as a new tool to promote it and to increase its value, applying a territorial context related methodology founded on scientific evidence.
Microscopic dynamics of plasmas and chaos
International Nuclear Information System (INIS)
Some of the key intellectual foundations of plasma physics are in danger of becoming a lost art. Fortunately, however, this threat recedes with the publication of this valuable book. It renders accessible those aspects of theoretical plasma physics that are best approached from the perspectives of classical mechanics, in both its early nineteenth century and late twentieth century manifestations. Half a century has elapsed since the publication of seminal papers such as those by Bohm and Pines (1951), van Kampen (1955), and Bernstein, Greene and Kruskal (1957). These papers served to address a fundamental question of physics - namely the relation between degrees of freedom that exist at the individual particle level of description, and those that exist at the collective level - in the plasma context. The authors of the present book have played a major role in the investigation of this question from an N-body standpoint, which can be divided into two linked themes. First, those topics that can be illuminated by analytical methods that lie in the tradition of classical mechanics that stretches back to Lagrange, Legendre and Hamilton. Second, those topics that benefit from the insights developed following the redevelopment of classical mechanics in relation to chaos theory in the 1980s and subsequently. The working plasma physicist who wishes to dig more deeply in this field is faced at present with a number of challenges. These may include a perception that this subfield is of limited relevance to mission-oriented questions of plasma performance; a perception of the research literature as being self-contained and inaccessible; and, linked to this, unfamiliarity with the mathematical tools. The latter problem is particularly pressing, given the limited coverage of classical mechanics in many undergraduate physics courses. The book by Elskens and Escande meets many of the challenges outlined above. The rewards begin early, by the end of the second chapter, with
Directory of Open Access Journals (Sweden)
Évelyne Prioux
2011-07-01
Full Text Available Plusieurs élégies rassemblées dans les Aitia de Callimaque s'attachent à expliquer les origines de tel ou tel culte ou d’une iconographie inattendue dont le temps a pu obscurcir la signification. Le recueil de Callimaque constitue ainsi un témoignage précieux sur la statuaire archaïque et sur sa réception auprès des érudits de l’époque hellénistique. Le présent article cherche à expliquer les choix opérés par Callimaque au sein de cette présentation de l’art archaïque : loin d'être disposées sans ordre, les notices rassemblées par Callimaque obéissent à des logiques de sélection et de classement que le lecteur moderne peut encore deviner. Par delà l’apparent désordre des fragments d’ecphraseis livrés par les découvertes papyrologiques, on perçoit que les poèmes que Callimaque a consacrés aux origines de la statuaire formaient probablement un tout signifiant. Le discours sur les statues sert ainsi de support à l’expression de positions éthiques, esthétiques et politiques : des images archaïques, telles que l’Apollon délien de Tectaios et d’Angélion ou une Héra de Samos, sont par exemple relues et réinterprétées dans l’intention d’inventer un passé susceptible de justifier les innovations politiques de la cour alexandrine et de les ancrer dans des interprétations iconographiques que le poète invente peut-être, bien qu’il feigne de les tirer de l’oubli. Pour ce faire, il applique aux images archaïques des techniques d’analyse allégorique qui sont sans doute directement inspirées par l'exégèse du texte homérique.Several fragmentary elegies of Callimachus’ Aitia were meant to explain the origins of a given cult or of a strange iconography whose meaning had been obscured by the passing of time. The Aitia are thus a very important source on archaic sculpture and on its reception in Hellenistic times. This paper attempts to explain how Callimachus selected the statues that
Outflow channel sources, reactivation, and chaos formation, Xanthe Terra, Mars
Rodriguez, J.A.P.; Sasaki, S.; Kuzmin, R.O.; Dohm, J.M.; Tanaka, K.L.; Miyamoto, H.; Kurita, K.; Komatsu, G.; Fairen, A.G.; Ferris, J.C.
2005-01-01
The undulating, warped, and densely fractured surfaces of highland regions east of Valles Marineris (located north of the eastern Aureum Chaos, east of the Hydraotes Chaos, and south of the Hydaspis Chaos) resulted from extensional surface warping related to ground subsidence, caused when pressurized water confined in subterranean caverns was released to the surface. Water emanations formed crater lakes and resulted in channeling episodes involved in the excavation of Ares, Tiu, and Simud Valles of the eastern part of the circum-Chryse outflow channel system. Progressive surface subsidence and associated reduction of the subsurface cavernous volume, and/or episodes of magmatic-driven activity, led to increases of the hydrostatic pressure, resulting in reactivation of both catastrophic and non-catastrophic outflow activity. Ancient cratered highland and basin materials that underwent large-scale subsidence grade into densely fractured terrains. Collapse of rock materials in these regions resulted in the formation of chaotic terrains, which occur in and near the headwaters of the eastern circum-Chryse outflow channels. The deepest chaotic terrain in the Hydaspis Chaos region resulted from the collapse of pre-existing outflow channel floors. The release of volatiles and related collapse may have included water emanations not necessarily linked to catastrophic outflow. Basal warming related to dike intrusions, thermokarst activity involving wet sediments and/or dissected ice-enriched country rock, permafrost exposed to the atmosphere by extensional tectonism and channel incision, and/or the injection of water into porous floor material, may have enhanced outflow channel floor instability and subsequent collapse. In addition to the possible genetic linkage to outflow channel development dating back to at least the Late Noachian, clear disruption of impact craters with pristine ejecta blankets and rims, as well as preservation of fine tectonic fabrics, suggest that
Intrinsic Instability of Coronal Streamers
Chen, Y; Song, H Q; Shi, Q Q; Feng, S W; Xia, L D; 10.1088/0004-637X/691/2/1936
2009-01-01
Plasma blobs are observed to be weak density enhancements as radially stretched structures emerging from the cusps of quiescent coronal streamers. In this paper, it is suggested that the formation of blobs is a consequence of an intrinsic instability of coronal streamers occurring at a very localized region around the cusp. The evolutionary process of the instability, as revealed in our calculations, can be described as follows: (1) through the localized cusp region where the field is too weak to sustain the confinement, plasmas expand and stretch the closed field lines radially outward as a result of the freezing-in effect of plasma-magnetic field coupling; the expansion brings a strong velocity gradient into the slow wind regime providing the free energy necessary for the onset of a subsequent magnetohydrodynamic instability; (2) the instability manifests itself mainly as mixed streaming sausage-kink modes, the former results in pinches of elongated magnetic loops to provoke reconnections at one or many loc...
Chaos and maps in relativistic rynamical systems
Directory of Open Access Journals (Sweden)
L. P. Horwitz
2000-01-01
Full Text Available The basic work of Zaslavskii et al showed that the classical non-relativistic electromagnetically kicked oscillator can be cast into the form of an iterative map on the phase space; the resulting evolution contains a stochastic flow to unbounded energy. Subsequent studies have formulated the problem in terms of a relativistic charged particle in interaction with the electromagnetic field. We review the structure of the covariant Lorentz force used to study this problem. We show that the Lorentz force equation can be derived as well from the manifestly covariant mechanics of Stueckelberg in the presence of a standard Maxwell field, establishing a connection between these equations and mass shell constraints. We argue that these relativistic generalizations of the problem are intrinsically inaccurate due to an inconsistency in the structure of the relativistic Lorentz force, and show that a reformulation of the relativistic problem, permitting variations (classically in both the particle mass and the effective “mass” of the interacting electromagnetic field, provides a consistent system of classical equations for describing such processes.
Laser dynamical reservoir computing with consistency: an approach of a chaos mask signal.
Nakayama, Joma; Kanno, Kazutaka; Uchida, Atsushi
2016-04-18
We numerically investigate reservoir computing based on the consistency of a semiconductor laser subjected to optical feedback and injection. We introduce a chaos mask signal as an input temporal mask for reservoir computing and perform a time-series prediction task. We compare the errors of the task obtained from the chaos mask signal with those obtained from other digital and analog masks. The performance of the prediction task can be improved by using the chaos mask signal due to complex dynamical response.
The design and research of anti-color-noise chaos M-ary communication system
Yongqing Fu; Xingyuan Li; Yanan Li; Lin Zhang
2016-01-01
Previously a novel chaos M-ary digital communication method based on spatiotemporal chaos Hamilton oscillator has been proposed. Without chaos synchronization circumstance, it has performance improvement in bandwidth efficiency, transmission efficiency and anti-white-noise performance compared with traditional communication method. In this paper, the channel noise influence on chaotic modulation signals and the construction problem of anti-color-noise chaotic M-ary communication system are st...
Recursive proportional feedback and its use to control chaos in an electrochemical system
Rollins, R W; Sherard, P; Dewald, H D
1995-01-01
The recursive proportional feedback (RPF) algorithm for controlling chaos is described and applied to control chemical chaos observed during the electrodissolution of a rotating copper disk in a sodium acetate/acetic acid buffer. Experimental evidence is presented to indicate why the RPF method was used and the theoretical robustness of the algorithm is discussed. (This paper appears in the "Proceedings of the 2nd Conference on EXPERIMENTAL CHAOS," World Scientific Press, River Ridge, NJ, 1995)
Chaos synchronization between two different 4D hyperchaotic Chen systems
Institute of Scientific and Technical Information of China (English)
Liu Yang-Zheng; Jiang Chang-Sheng; Lin Chang-Sheng; Jiang Yao-Mei
2007-01-01
This paper presents chaos synchronization between two different four-dimensional (4D) hyperchaotic Chen systems by nonlinear feedback control laws.A modified 4D hyperchaotic Chen system is obtained by changing the nonlinear function of the 4D hyperchaotic Chen system,furthermore,an electronic circuit to realize two different 4D hyperchaotic Chen systems is designed.With nonlinear feedback control method,chaos synchronization between two different 4D hyperchaotic Chen systems is achieved.Based on the stability theory,the functions of the nonlinear feedback control for synchronization of two different 4D hyperchaotic Chen systems is derived,the range of feedback gains is determined.Numerical simulations are shown to verify the theoretical results.
Asymptotic chaos expansions in finance theory and practice
Nicolay, David
2014-01-01
Stochastic instantaneous volatility models such as Heston, SABR or SV-LMM have mostly been developed to control the shape and joint dynamics of the implied volatility surface. In principle, they are well suited for pricing and hedging vanilla and exotic options, for relative value strategies or for risk management. In practice however, most SV models lack a closed form valuation for European options. This book presents the recently developed Asymptotic Chaos Expansions methodology (ACE) which addresses that issue. Indeed its generic algorithm provides, for any regular SV model, the pure asymptotes at any order for both the static and dynamic maps of the implied volatility surface. Furthermore, ACE is programmable and can complement other approximation methods. Hence it allows a systematic approach to designing, parameterising, calibrating and exploiting SV models, typically for Vega hedging or American Monte-Carlo. Asymptotic Chaos Expansions in Finance illustrates the ACE approach for single underlyings (suc...
Catastrophic ice lake collapse in Aram Chaos, Mars
Roda, Manuel; Zegers, Tanja E; Oosthoek, Jelmer H P
2014-01-01
Hesperian chaotic terrains have been recognized as the source of outflow channels formed by catastrophic outflows. Four main scenarios have been proposed for the formation of chaotic terrains that involve different amounts of water and single or multiple outflow events. Here, we test these scenarios with morphological and structural analyses of imagery and elevation data for Aram Chaos in conjunction with numerical modeling of the morphological evolution of the catastrophic carving of the outflow valley. The morphological and geological analyses of Aram Chaos suggest large-scale collapse and subsidence (1500 m) of the entire area, which is consistent with a massive expulsion of liquid water from the subsurface in one single event. The combined observations suggest a complex process starting with the outflow of water from two small channels, followed by continuous groundwater sapping and headward erosion and ending with a catastrophic lake rim collapse and carving of the Aram Valley, which is synchronous with ...
Intermittency and chaos in intracavity doubled lasers. II
Energy Technology Data Exchange (ETDEWEB)
James, G.E.; Harrell, E.M. II (School of Mathematics, Georgia Institute of Technology, Atlanta, Georgia 30332 (USA)); Roy, R. (School of Physics, Georgia Institute of Technology, Atlanta, Georgia 30332 (USA))
1990-03-01
We describe the nonlinear dynamics of intracavity doubled multimode lasers. Baer (J. Opt. Soc. Am. B 3, 1175 (1986)) observed irregular amplitude fluctuations in a multimode yttrium aluminum garnet laser with an intracavity potassium titanyl phosphate frequency-doubling crystal; we identify type-III intermittency as the route to chaos. Subsequently, Oka and Kubota (Opt. Lett. 13, 805 (1988)) demonstrated the stabilization of such a laser by the introduction of a quarter wave plate into the cavity. A generalized model of rate equations for this case is introduced. It is shown that a second route to chaos through a Hopf bifurcation, synchronization, and period-doubling sequence occurs on rotation of the quarter wave plate within the cavity. In addition, we predict that the laser output may be stable for particular lengths of the doubling crystal.
Randomness versus deterministic chaos: Effect on invasion percolation clusters
Peng, Chung-Kang; Prakash, Sona; Herrmann, Hans J.; Stanley, H. Eugene
1990-10-01
What is the difference between randomness and chaos \\? Although one can define randomness and one can define chaos, one cannot easily assess the difference in a practical situation. Here we compare the results of these two antipodal approaches on a specific example. Specifically, we study how well the logistic map in its chaotic regime can be used as quasirandom number generator by calculating pertinent properties of a well-known random process: invasion percolation. Only if λ>λ*1 (the first reverse bifurcation point) is a smooth extrapolation in system size possible, and percolation exponents are retrieved. If λ≠1, a sequential filling of the lattice with the random numbers generates a measurable anisotropy in the growth sequence of the clusters, due to short-range correlations.
Computational complexity of symbolic dynamics at the onset of chaos
Lakdawala, Porus
1996-05-01
In a variety of studies of dynamical systems, the edge of order and chaos has been singled out as a region of complexity. It was suggested by Wolfram, on the basis of qualitative behavior of cellular automata, that the computational basis for modeling this region is the universal Turing machine. In this paper, following a suggestion of Crutchfield, we try to show that the Turing machine model may often be too powerful as a computational model to describe the boundary of order and chaos. In particular we study the region of the first accumulation of period doubling in unimodal and bimodal maps of the interval, from the point of view of language theory. We show that in relation to the ``extended'' Chomsky hierarchy, the relevant computational model in the unimodal case is the nested stack automaton or the related indexed languages, while the bimodal case is modeled by the linear bounded automaton or the related context-sensitive languages.
Quantum biology on the edge of quantum chaos.
Directory of Open Access Journals (Sweden)
Gabor Vattay
Full Text Available We give a new explanation for why some biological systems can stay quantum coherent for a long time at room temperature, one of the fundamental puzzles of quantum biology. We show that systems with the right level of complexity between chaos and regularity can increase their coherence time by orders of magnitude. Systems near Critical Quantum Chaos or Metal-Insulator Transition (MIT can have long coherence times and coherent transport at the same time. The new theory tested in a realistic light harvesting system model can reproduce the scaling of critical fluctuations reported in recent experiments. Scaling of return probability in the FMO light harvesting complex shows the signs of universal return probability decay observed at critical MIT. The results may open up new possibilities to design low loss energy and information transport systems in this Poised Realm hovering reversibly between quantum coherence and classicality.
Climate predictions: the chaos and complexity in climate models
Mihailović, Dragutin T; Arsenić, Ilija
2013-01-01
Some issues which are relevant for the recent state in climate modeling have been considered. A detailed overview of literature related to this subject is given. The concept in modeling of climate, as a complex system, seen through Godel's Theorem and Rosen's definition of complexity and predictability is discussed. It is pointed out to occurrence of chaos in computing the environmental interface temperature from the energy balance equation given in a difference form. A coupled system of equations, often used in climate models is analyzed. It is shown that the Lyapunov exponent mostly has positive values allowing presence of chaos in this systems. The horizontal energy exchange between environmental interfaces, which is described by the dynamics of driven coupled oscillators, is analyzed. Their behavior and synchronization, when a perturbation is introduced in the system, as a function of the coupling parameters, the logistic parameter and the parameter of exchange, was studied calculating the Lyapunov expone...
Polynomial chaos expansion with random and fuzzy variables
Jacquelin, E.; Friswell, M. I.; Adhikari, S.; Dessombz, O.; Sinou, J.-J.
2016-06-01
A dynamical uncertain system is studied in this paper. Two kinds of uncertainties are addressed, where the uncertain parameters are described through random variables and/or fuzzy variables. A general framework is proposed to deal with both kinds of uncertainty using a polynomial chaos expansion (PCE). It is shown that fuzzy variables may be expanded in terms of polynomial chaos when Legendre polynomials are used. The components of the PCE are a solution of an equation that does not depend on the nature of uncertainty. Once this equation is solved, the post-processing of the data gives the moments of the random response when the uncertainties are random or gives the response interval when the variables are fuzzy. With the PCE approach, it is also possible to deal with mixed uncertainty, when some parameters are random and others are fuzzy. The results provide a fuzzy description of the response statistical moments.
Comparative study of variational chaos indicators and ODEs' numerical integrators
Darriba, Luciano A; Cincotta, Pablo M; Giordano, Claudia M
2012-01-01
The reader can find in the literature a lot of different techniques to study the dynamics of a given system and also, many suitable numerical integrators to compute them. Notwithstanding the recent work of Maffione et al. (2011a) for mappings, a detailed comparison among the widespread indicators of chaos in a general system is still lacking. Such a comparison could lead to select the most efficient algorithms given a certain dynamical problem. Furthermore, in order to choose the appropriate numerical integrators to compute them, more comparative studies among numerical integrators are also needed. This work deals with both problems. We first extend the work of Maffione et al. (2011) for mappings to the 2D H\\'enon & Heiles (1964) potential, and compare several variational indicators of chaos: the Lyapunov Indicator (LI); the Mean Exponential Growth Factor of Nearby Orbits (MEGNO); the Smaller Alignment Index (SALI) and its generalized version, the Generalized Alignment Index (GALI); the Fast Lyapunov Indi...
Chaos control and taming of turbulence in plasma devices
DEFF Research Database (Denmark)
Klinger, T.; Schröder, C.; Block, D.;
2001-01-01
Chaos and turbulence are often considered as troublesome features of plasma devices. In the general framework of nonlinear dynamical systems, a number of strategies have been developed to achieve active control over complex temporal or spatio-temporal behavior. Many of these techniques apply to...... plasma instabilities. In the present paper we discuss recent progress in chaos control and taming of turbulence in three different plasma "model" experiments: (1) Chaotic oscillations in simple plasma diodes, (2) ionization wave turbulence in the positive column of glow discharges, and (3) drift wave...... turbulence in a magnetized plasma column. Depending on the physical mechanism of the specific instability in each case, an appropriate control strategy is chosen out of a variety of different approaches; in particular discrete feedback, continuous feedback, or spatio-temporal open-loop synchronization...
Quantum mechanics with chaos correspondence principle, measurement and complexity
Kirilyuk, A P
1995-01-01
The true dynamical randomness is obtained as a natural fundamental property of deterministic quantum systems. It provides quantum chaos passing to the classical dynamical chaos under the ordinary semiclassical transition, which extends the correspondence principle to chaotic systems. In return one should accept the modified form of quantum formalism (exemplified by the Schrodinger equation) which, however, does not contradict the ordinary form, and the main postulates, of quantum mechanics. It introduces the principle of the fundamental dynamic multivaluedness extending the quantum paradigm to complex dynamical behaviour. Moreover, a causal solution to the well-known problems of the foundations of quantum mechanics, those of quantum indeterminacy and wave reduction, is also found using the same method. The concept of the fundamental dynamic uncertainty thus established is universal in character and provides a unified scheme of the complete description of arbitrary complex system of any origin. This scheme inc...
Intermittency and transient chaos from simple frequency-dependent selection.
Gavrilets, S; Hastings, A
1995-08-22
Frequency-dependent selection is an important determinant of the evolution of gametophytic self-incompatibility systems in plants, aposematic (warning) and cryptic coloration, systems of mimicry, competitive interactions among members of a population, mating preferences, predator-prey and host-parasite interactions, aggression and other behavioural traits. Past theoretical studies of frequency-dependent selection have shown it to be a plausible mechanism for the maintenance of genetic variability in natural populations. Here, through an analysis of a simple deterministic model for frequency-dependent selection, we demonstrate that complex dynamic behaviour is possible under a broad range of parameter values. In particular we show that the model exhibits not only cycles and chaos but also, for a more restricted set of parameters, transient chaos and intermittency: alterations between an apparently deterministic behaviour and apparently chaotic fluctuations. This behaviour, which has not been stressed within the population genetics literature, provides an explanation for erratic dynamics of gene frequencies.
Control of complex dynamics and chaos in distributed parameter systems
Energy Technology Data Exchange (ETDEWEB)
Chakravarti, S.; Marek, M.; Ray, W.H. [Univ. of Wisconsin, Madison, WI (United States)
1995-12-31
This paper discusses a methodology for controlling complex dynamics and chaos in distributed parameter systems. The reaction-diffusion system with Brusselator kinetics, where the torus-doubling or quasi-periodic (two characteristic incommensurate frequencies) route to chaos exists in a defined range of parameter values, is used as an example. Poincare maps are used for characterization of quasi-periodic and chaotic attractors. The dominant modes or topos, which are inherent properties of the system, are identified by means of the Singular Value Decomposition. Tested modal feedback control schemas based on identified dominant spatial modes confirm the possibility of stabilization of simple quasi-periodic trajectories in the complex quasi-periodic or chaotic spatiotemporal patterns.
Universality in Chaos of Particle Motion near Black Hole Horizon
Hashimoto, Koji
2016-01-01
Motion of a particle near a horizon of a spherically symmetric black hole is shown to possess a universal Lyapunov exponent of a chaos provided by its surface gravity. To probe the horizon, we introduce electromagnetic or scalar force to the particle so that it does not fall into the horizon. There appears an unstable maximum of the total potential where the evaluated maximal Lyapunov exponent is found to be independent of the external forces and the particle mass. The Lyapunov exponent is universally given by the surface gravity of the black hole. Unless there are other sources of a chaos, the Lyapunov exponent is subject to an inequality $\\lambda \\leq 2\\pi T_{\\rm BH}/\\hbar$, which is identical to the bound recently discovered by Maldacena, Shenker and Stanford.
From Hamiltonian chaos to complex systems a nonlinear physics approach
Leonetti, Marc
2013-01-01
From Hamiltonian Chaos to Complex Systems: A Nonlinear Physics Approach collects contributions on recent developments in non-linear dynamics and statistical physics with an emphasis on complex systems. This book provides a wide range of state-of-the-art research in these fields. The unifying aspect of this book is a demonstration of how similar tools coming from dynamical systems, nonlinear physics, and statistical dynamics can lead to a large panorama of research in various fields of physics and beyond, most notably with the perspective of application in complex systems. This book also: Illustrates the broad research influence of tools coming from dynamical systems, nonlinear physics, and statistical dynamics Adopts a pedagogic approach to facilitate understanding by non-specialists and students Presents applications in complex systems Includes 150 illustrations From Hamiltonian Chaos to Complex Systems: A Nonlinear Physics Approach is an ideal book for graduate students and researchers working in applied...
Impulse-induced localized control of chaos in starlike networks
Chacón, Ricardo; Palmero, Faustino; Cuevas-Maraver, Jesús
2016-06-01
Locally decreasing the impulse transmitted by periodic pulses is shown to be a reliable method of taming chaos in starlike networks of dissipative nonlinear oscillators, leading to both synchronous periodic states and equilibria (oscillation death). Specifically, the paradigmatic model of damped kicked rotators is studied in which it is assumed that when the rotators are driven synchronously, i.e., all driving pulses transmit the same impulse, the networks display chaotic dynamics. It is found that the taming effect of decreasing the impulse transmitted by the pulses acting on particular nodes strongly depends on their number and degree of connectivity. A theoretical analysis is given explaining the basic physical mechanism as well as the main features of the chaos-control scenario.
Texture features from Chaos Game Representation Images of Genomes
Directory of Open Access Journals (Sweden)
Vrinda V. Nair
2013-04-01
Full Text Available The proposed work investigates the effectiveness of coarse measures of the Chaos Game Representation (CGR images in differentiating genomes of various organisms. Major work in this area is seen to focus on feature extraction using Frequency Chaos Game Representation (FCGR matrices. Although it is biologically significant, FCGR matrix has an inherent error which is associated with the insufficient computing as well as the screen resolutions. Hence the CGR image is converted to a texture image and corresponding feature vectors extracted. Features such as the texture properties and the subsequent wavelet coefficients of the texture image are used. Our work suggests that texture features characterize genomes well further; their wavelet coefficients yield better distinguishing capabilities.
Is there chaos in the Spanish labour market?
International Nuclear Information System (INIS)
Highlights: We consider Spanish unemployment time series. We apply a number of nonlinearity tests and chaoticity measures. We establish the presence of nonlinearity and chaos, which disappears when the data are shuffled. Abstract: One could argue that there is a resurgence of the non-linear modelling in economics. Some instruments have been developed to measure the complexity or instability of the analysed systems. At the present work some of these developed techniques are applied to verify the non-linearity present in the time series of Spanish unemployment, as well as to quantify the degree of complexity of the system that has generated the series. Using these techniques we find evidence of chaos in Spanish unemployment time series.
Hypersensitivity and chaos signatures in the quantum baker's maps
Scott, A J; Caves, C M; Schack, R; Brun, Todd A.; Caves, Carlton M.; Schack, Ruediger
2006-01-01
Classical chaotic systems are distinguished by their sensitive dependence on initial conditions. The absence of this property in quantum systems has lead to a number of different criteria being proposed for quantum chaos, including linear growth of entropy, exponential decay of fidelity, and hypersensitivity to perturbation. All of these accurately predict chaos in the classical limit, but it is not clear that they behave the same far from the classical realm. We investigate the dynamics of a family of quantizations of the baker's map, which range from a highly entangling unitary transformation to an essentially trivial shift map. Linear entropy growth and fidelity decay are exhibited by this entire family of maps, but hypersensitivity distinguishes between the simple dynamics of the trivial shift map and the more complicated dynamics of the other quantizations. This is supported by an analytical argument for short times and numerical evidence at later times.
CHAOS SYNCHRONIZATION OF MORSE OSCILLATOR VIA BACKSTEPPING DESIGN
Institute of Scientific and Technical Information of China (English)
无
2006-01-01
Synchronization and adaptive synchronization of Morse oscillator with periodic forced section is investigated in this paper. Backstepping design is a recursive procedure that combines the choice of Lyapunov function with the design of controller. The proposed approaches offers a syetematic design procedure for synchronization and adaptive synchronization of a large class of continuous-time chaotic systems in the chaos research literature. Simulation results are presented to show the effectiveness of the ...
Geology and Origin of Europa's Mitten Feature (Murias Chaos)
Figueredo, P. H.; Chuang, F. C.; Rathbun, J.; Kirk, R. L.; Greeley, R.
2002-01-01
The "Mitten" (provisionally named Murias Chaos by the International Astronomical Union) is a region of elevated chaos-like terrain in the leading hemisphere of Europa. Its origin had been explained under the currently debated theories of melting through a thin lithosphere or convection within a thick one. Galileo observations reveal several characteristics that suggest that the Mitten is distinct from typical chaos terrain and point to a different formational process. Photoclinometric elevation estimates suggest that the Mitten is slightly elevated with respect to the surrounding terrain; geologic relations indicate that it must have raised significantly from the plains in its past, resembling disrupted domes on Europa's trailing hemisphere. Moreover, the Mitten material appears to have extruded onto the plains and flowed for tens of kilometers. The area subsequently subsided as a result of isostatic adjustment, viscous relaxation, and/or plains loading. Using plate flexure models, we estimated the elastic lithosphere in the area to be several kilometers thick. We propose that the Mitten originated by the ascent and extrusion of a large thermal diapir. Thermal-mechanical modeling shows that a Mitten-sized plume would remain sufficiently warm and buoyant to pierce through the crust and flow unconfined on the surface. Such a diapir probably had an initial radius between 5 and 8 km and an initial depth of 20-40 km, consistent with a thick-lithosphere model. In this scenario the Mitten appears to represent the surface expression of the rare ascent of a large diapir, in contrast to lenticulae and chaos terrain, which may form by isolated and clustered small diapirs, respectively.
Doubly excited helium. From strong correlation to chaos
International Nuclear Information System (INIS)
In the present dissertation, the double excitation states of helium including the autoionization decay of these states were studied experimentally and theoretically in a broad energy region, which includes the transition from strong correlation below the low single ionization thresholds (SIT) to the region of quantum chaos at energies very close to the double-ionization threshold. Two kind of experiments were performed, namely total-ion-yield measurements with the aim to observe total cross sections (TCS) and electron time-of-flight (TOF) measurements to obtain partial cross sections (PCS) as well as angular distribution parameters (ADP). Both types of measurements were performed at the third generation synchrotron radiation facility BESSY II in Berlin. The TCSs were recorded up to the SIT I15, and they were found to be in in excellent agreement with state-of-the-art complex-rotation calculations performed recently by D. Delande. These experimental and theoretical data on the TCSs were analyzed in order to study quantum chaos in doubly excited helium, and interesting signatures of quantum chaos were found. The TOF technique allowed to measure PCSs and ADPs in the energy regions from I5 to I9 and I7, respectively. These experimental data provide a critical assessment of theoretical models that can be used to explore the dynamics of strong correlation as well as quantum chaos in helium. In the theoretical part of this dissertation, the n- and l-specific PCSs and ADPs below I4 were calculated employing the R-matrix method. The present theoretical results agree well with a recent experimental study of l-specific PCSs below I4 by J.R. Harries et al. An analysis of patterns in the PCSs and ADPs on the basis of the present experimental and theoretical l-specific data allowed to improve the present understanding of autoionization decay dynamics in this two-electron atom. (orig.)
Chaos-Based Image Encryption Algorithm Using Decomposition
Xiuli Song; Hongyao Deng
2013-01-01
The proposed chaos-based image encryption algorithm consists of four stages: decomposition, shuffle, diffusion and combination. Decomposition is that an original image is decomposed to components according to some rule. The purpose of the shuffle is to mask original organization of the pixels of the image, and the diffusion is to change their values. Combination is not necessary in the sender. To improve the efficiency, the parallel architecture is taken to process the shuffle and diffusion. ...
From Chaos to Calm understanding Anger in Urban Adolescent Males
Montgomery, June M.
2010-01-01
From Chaos to Calm Understanding Anger in Urban Adolescent Males by June Mardell Montgomery (ABSTRACT) This work is based on the premise that uncontrolled anger contributes to the violence committed by adolescent boys 13-17 years of age. In fact, in all countries, young males are both the principal perpetrators and victims of homicide (World Health Organization, 2002). Identifying the underlying reasons for the anger is instrumental in controlling this emotion and in develop...
SAMBA: Sparse Approximation of Moment-Based Arbitrary Polynomial Chaos
Ahlfeld, R.; Belkouchi, B.; Montomoli, F.
2016-09-01
A new arbitrary Polynomial Chaos (aPC) method is presented for moderately high-dimensional problems characterised by limited input data availability. The proposed methodology improves the algorithm of aPC and extends the method, that was previously only introduced as tensor product expansion, to moderately high-dimensional stochastic problems. The fundamental idea of aPC is to use the statistical moments of the input random variables to develop the polynomial chaos expansion. This approach provides the possibility to propagate continuous or discrete probability density functions and also histograms (data sets) as long as their moments exist, are finite and the determinant of the moment matrix is strictly positive. For cases with limited data availability, this approach avoids bias and fitting errors caused by wrong assumptions. In this work, an alternative way to calculate the aPC is suggested, which provides the optimal polynomials, Gaussian quadrature collocation points and weights from the moments using only a handful of matrix operations on the Hankel matrix of moments. It can therefore be implemented without requiring prior knowledge about statistical data analysis or a detailed understanding of the mathematics of polynomial chaos expansions. The extension to more input variables suggested in this work, is an anisotropic and adaptive version of Smolyak's algorithm that is solely based on the moments of the input probability distributions. It is referred to as SAMBA (PC), which is short for Sparse Approximation of Moment-Based Arbitrary Polynomial Chaos. It is illustrated that for moderately high-dimensional problems (up to 20 different input variables or histograms) SAMBA can significantly simplify the calculation of sparse Gaussian quadrature rules. SAMBA's efficiency for multivariate functions with regard to data availability is further demonstrated by analysing higher order convergence and accuracy for a set of nonlinear test functions with 2, 5 and 10
Self-Stable Chaos Control of dc-dc Converter
Institute of Scientific and Technical Information of China (English)
LU Wei-Guo; ZHOU Luo-Wei; WU Jun-Ke
2009-01-01
A new concept related to self-stable chaos control is first put forward,and its theoretical basis and realization are presented from the frequency-domain perspective. With a new analogous-circuit realization of this control its applications in the voltage-mode Buck converter is discussed. The harmonic-balance method is applied to determine the control range of the control parameter.The experiment results given in the last part confirm the validity of the proposed control method.
Transition to Quantum Chaos in Weakly Disordered Graphene Nanoflakes
Rycerz, Adam
2011-01-01
We analyze numerically ensembles of tight-binding Hamiltonians describing highly-symmetric graphene nanoflakes with weak diagonal disorder induced by random electrostatic potential landscapes. When increasing the disorder strength, statistical distribution of energy levels evolves from Poissonian to Wigner, indicating the transition to quantum chaos. Power laws with the universal exponent map the disorder strength in nanoflakes of different sizes, boundaries, and microscopic disorder types on...
Decoherence and the Branching of Chaos-less Classical Trajectory
Ishikawa, Takuji
2016-01-01
This study was started to know mysterious classicality of nuclei. This time, I found a new rule for decoherence. I used a model without chaos. As a result, it was shown that not only the intersection of classical trajectories but also branching of classical trajectories are needed for decoherence. In other words, it was shown that interactions between a main system and environments have to make enough branchings of classical trajectories of the main system for decoherence.
Quantum interference vs. quantum chaos in the nuclear shell model
International Nuclear Information System (INIS)
In this paper we study the complexity of the nuclear states in terms of a two body quadupole-quadrupole interaction. Energy distributions and eigenvectors composition exhibit a visible interference pattern which is dependent on the intensity of the interaction. In analogy with optics, the visibility of the interference is related to the purity of the states, therefore, we show that the fluctuations associated with quantum chaos have as their origin the remaining quantum coherence with a visibility magnitude close to 5%
Chaos in Temperature in Generic 2p-Spin Models
Panchenko, Dmitry
2016-02-01
We prove chaos in temperature for even p-spin models which include sufficiently many p-spin interaction terms. Our approach is based on a new invariance property for coupled asymptotic Gibbs measures, similar in spirit to the invariance property that appeared in the proof of ultrametricity in Panchenko (Ann Math (2) 177(1):383-393, 2013), used in combination with Talagrand's analogue of Guerra's replica symmetry breaking bound for coupled systems.
Chaos detection tools: The LP-VIcode and its applications
Darriba, L. A.; Maffione, N. P.; Cincotta, P. M.; Giordano, C. M.
A very important topic in galactic dynamics is the detection of instabilities of a given system and the possible appearance of chaos. Such a chaotic bahaviour can be detected and studied by means of variational chaos in- dicators (CIs). The CIs are based on the study of the evolution of initial deviation vectors, which makes these techniques specially sensitive to in- dicate the presence of chaos. Notwithstanding their special sensitiveness to identify chaos, the CIs are still good alternatives to determine also the resonance web. On the other hand, the so-called spectral analysis methods are based on the study of some quantity (e.g. the frequency) on a single orbit, which turns these techniques very efficient for the determination of the resonant struc- ture of the system. The analysis of the interaction among chaotic and regular components as well as the determination of the resonant structure of the Hamiltonian leads to a deeper understanding of the system's dynamics. Despite the advan- tages of the simultaneous application of both types of techniques, many researchers keep applying only one of them. Herein, we present an alpha version of a program coded in Fortran, the LP-VIcode. Although the code is in a developing stage, it can compute several CIs, and here we apply it together with the Frequency Modified Fourier Transform (FMFT) (Sidlichovský & Nesvorný 1996) to study the stationary space (Schwarzchild 1993) of an average realistic Hamiltonian model (Muzzio et al. 2005). Using the LP-VIcode, in Maffione et al. (2011b) and Darriba et al. (sub- mitted) the authors suggest an efficient package of CIs to study a general Hamiltonian. Here the research is extended to show that the complemen- tary use of the LP-VIcode and the spectral analysis methods is highly rec- ommended to study a realistic Hamiltonian model.
Chaos in extended linear arrays of Josephson weak links
Energy Technology Data Exchange (ETDEWEB)
Nerenberg, M.A.H.; Spiteri, R.J. (Department of Applied Mathematics, University of Western Ontario, London, Ontario, Canada N6A 5B9 (CA)); Blackburn, J.A. (Department of Physics and Computing, Wilfred Laurier University, Waterloo, Ontario, Canada N2L 3C5 (CA))
1989-12-01
Extended linear arrays of interacting Josephson weak links are studied by numerical simulation using the resistively shunted junction model. The minimum coupling strength for chaotic behavior is determined as a function of the number of links. This strength is found to diminish steadily with increasing number, despite the inclusion of only nearest-neighbor interaction. The implications for Josephson technology are briefly discussed. Mathematically, the results are confirmation of the Ruelle-Takens scenario for chaos.
Period doubling route to chaos in Taylor-Green dynamo
Yadav, R; Verma, M K; Paul, S; Wahi, P
2010-01-01
We perform spectral simulations of dynamo for magnetic Prandtl number of one with Taylor-Green forcing. We observe dynamo transition through a supercritical pitchfork bifurcation. Beyond the transition, the numerical simulations reveal complex dynamo states with windows of constant, periodic, quasiperiodic, and chaotic magnetic field configurations. For some forcing amplitudes, multiple attractors were obtained for different initial conditions. We show that one of the chaotic windows follows the period-doubling route to chaos.
A survey on delayed feedback control of chaos
Institute of Scientific and Technical Information of China (English)
Yuping TIAN; Jiandong ZHU; Guanrong CHEN
2005-01-01
This paper introduces the basic idea and provides the mathematical formulation of the delayed feedback control (DFC) methodology, which has been widely used in chaos control. Stability analysis including the well-known odd number limitation of the DFC is reviewed. Some new developments in characterizing the limitation of the DFC are presented. Various modified DFC methods, which are developed in order to overcome the odd number limitation, are also described. Finally, some open problems in this research field are discussed.
Lecture notes on Gaussian multiplicative chaos and Liouville Quantum Gravity
Rhodes, Rémi; Vargas, Vincent
2016-01-01
The purpose of these notes, based on a course given by the second author at Les Houches summer school, is to explain the probabilistic construction of Polyakov's Liouville quantum gravity using the theory of Gaussian multiplicative chaos. In particular, these notes contain a detailed description of the so-called Liouville measures of the theory and their conjectured relation to the scaling limit of large planar maps properly embedded in the sphere. These notes are rather short and require no ...
Quantum dissipative chaos in the statistics of excitation numbers
Kryuchkyan, Gagik Yu.; Manvelyan, Suren B.
2001-01-01
A quantum manifestation of chaotic classical dynamics is found in the framework of oscillatory numbers statistics for the model of nonlinear dissipative oscillator. It is shown by numerical simulation of an ensemble of quantum trajectories that the probability distributions and variances of oscillatory number states are strongly transformed in the order-to-chaos transition. The nonclassical, sub-Poissonian statistics of oscillatory excitation numbers is established for chaotic dissipative dyn...
Bifurcation, Period Doublings and Chaos in Clarinetlike Systems
Maganza, Christian; Causse, René; Laloë, Franck
1986-01-01
cote interne IRCAM: Maganza86a / National audience Wind instrument provide interesting hydrodynamical systems where non-linearities are importantbut well localized. A simple analysis shows that these systems should undergo Feigenbaum-typeroute to chaos, with a cascade of period doublings. Experiments have been performed with anacoustical resonator and an "artificial" excitation (nonlinearities controlled by either analogic ordigital devices); they have confirmed these predictions.
Synchronization of chaos in non-identical parametrically excited systems
Energy Technology Data Exchange (ETDEWEB)
Idowu, B.A. [Department of Physics, Lagos State University, Ojo (Nigeria)], E-mail: babaidowu@yahoo.com; Vincent, U.E. [Department of Physics, Olabisi Onabanjo University, P.M.B 2002, Ago-Iwoye (Nigeria)], E-mail: ue_vincent@yahoo.com; Njah, A.N. [Department of Physics, University of Agriculture, Abeokuta (Nigeria)
2009-03-15
In this paper, we investigate the synchronization of chaotic systems consisting of non-identical parametrically excited oscillators. The active control technique is employed to design control functions based on Lyapunov stability theory and Routh-Hurwitz criteria so as to achieve global chaos synchronization between a parametrically excited gyroscope and each of the parametrically excited pendulum and Duffing oscillator. Numerical simulations are implemented to verify the results.
Two-mode chaos and its synchronization properties
DEFF Research Database (Denmark)
Postnov, D.E.; Shishkin, A.V.; Sosnovtseva, Olga;
2005-01-01
Using a simple model with bimodal dynamics, we investigate the intra- and inter-system entrainment of the two different time scales involved in the chaotic oscillations. The transition between mode-locked and mode-unlocked chaos is analyzed for a single system. For coupled oscillators, we...... demonstrate full and partial synchronization patterns depending on the adjustment between the fast and slow time scales and reveal the embedded structure of the corresponding synchronization regions....
Nonlinear internal friction, chaos, fractal and musical instruments
International Nuclear Information System (INIS)
Nonlinear and structure sensitive internal friction phenomena in materials are used for characterizing musical instruments. It may be one of the most important factors influencing timbre of instruments. As a nonlinear dissipated system, chaos and fractals are fundamental peculiarities of sound spectra. It is shown that the concept of multi range fractals can be used to decompose the frequency spectra of melody. New approaches are suggested to improve the fabrication, property characterization and physical understanding of instruments. (author). 18 refs, 4 figs
Controlling Halo-Chaos via Variable Structure Method
Institute of Scientific and Technical Information of China (English)
方锦清; 于星火; 陈关荣
2003-01-01
We propose a variable structure control method which is another innovative technique for suppressing beam halochaos in the periodic focusing channels of high-current proton beam accelerator, which belongs to a high-tech field.The analysis and numerical results show that the method is effective for controlling beam halo-chaos. Physical implementation of such a kind of control strategy remains an important and open issue for further applications.
Doubly excited helium. From strong correlation to chaos
Energy Technology Data Exchange (ETDEWEB)
Jiang, Yuhai
2006-03-15
In the present dissertation, the double excitation states of helium including the autoionization decay of these states were studied experimentally and theoretically in a broad energy region, which includes the transition from strong correlation below the low single ionization thresholds (SIT) to the region of quantum chaos at energies very close to the double-ionization threshold. Two kind of experiments were performed, namely total-ion-yield measurements with the aim to observe total cross sections (TCS) and electron time-of-flight (TOF) measurements to obtain partial cross sections (PCS) as well as angular distribution parameters (ADP). Both types of measurements were performed at the third generation synchrotron radiation facility BESSY II in Berlin. The TCSs were recorded up to the SIT I{sub 15}, and they were found to be in in excellent agreement with state-of-the-art complex-rotation calculations performed recently by D. Delande. These experimental and theoretical data on the TCSs were analyzed in order to study quantum chaos in doubly excited helium, and interesting signatures of quantum chaos were found. The TOF technique allowed to measure PCSs and ADPs in the energy regions from I{sub 5} to I{sub 9} and I{sub 7}, respectively. These experimental data provide a critical assessment of theoretical models that can be used to explore the dynamics of strong correlation as well as quantum chaos in helium. In the theoretical part of this dissertation, the n- and l-specific PCSs and ADPs below I{sub 4} were calculated employing the R-matrix method. The present theoretical results agree well with a recent experimental study of l-specific PCSs below I{sub 4} by J.R. Harries et al. An analysis of patterns in the PCSs and ADPs on the basis of the present experimental and theoretical l-specific data allowed to improve the present understanding of autoionization decay dynamics in this two-electron atom. (orig.)
Characterizing Weak Chaos using Time Series of Lyapunov Exponents
da Silva, R. M.; Manchein, C.; Beims, M. W.; Altmann, E. G.
2015-01-01
We investigate chaos in mixed-phase-space Hamiltonian systems using time series of the finite- time Lyapunov exponents. The methodology we propose uses the number of Lyapunov exponents close to zero to define regimes of ordered (stickiness), semi-ordered (or semi-chaotic), and strongly chaotic motion. The dynamics is then investigated looking at the consecutive time spent in each regime, the transition between different regimes, and the regions in the phase-space associated to them. Applying ...
A New Nonrecursive Pseudorandom Number Generator Based on Chaos Mappings
Yaguchi, Hirotake; Kubo, Izumi
2008-01-01
We introduce a new pseudorandom number generator SSR (the Simplified Shift-Real random number generator) which generates the k-th random number nonrecursively (directly) based on chaos mappings on the interval [1,2). We investigate properties of SSR random numbers and give the theoretical background of generation of random numbers. A practical integral(all-integer) version SSI of SSR, which is suitable for parallel computation, is also provided.
The Origin of Chaos in the Outer Solar System
Murray, N; Holman, M.
1999-01-01
Classical analytic theories of the solar system indicate that it is stable, but numerical integrations suggest that it is chaotic. This disagreement is resolved by a new analytic theory. The theory shows that the chaos among the Jovian planets results from the overlap of the components of a mean motion resonance among Jupiter, Saturn, and Uranus, and provides rough estimates of the Lyapunov time (10 million years) and the dynamical lifetime of Uranus (10^{18} years). The Jovian planets must h...
Synchronization and suppression of chaos in non-locally coupled map lattices
Indian Academy of Sciences (India)
R M Szmoski; S E De S Pinto; M T Van Kan; A M Batista; R L Viana; S R Lopes
2009-12-01
We considered coupled map lattices with long-range interactions to study the spatiotemporal behaviour of spatially extended dynamical systems. Coupled map lattices have been intensively investigated as models to understand many spatiotemporal phenomena observed in extended system, and consequently spatiotemporal chaos. We used the complex order parameter to quantify chaos synchronization for a one-dimensional chain of coupled logistic maps with a coupling strength which varies with the lattice in a power-law fashion. Depending on the range of the interactions, complete chaos synchronization and chaos suppression may be attained. Furthermore, we also calculated the Lyapunov dimension and the transversal distance to the synchronization manifold.
Experimental study of the effect of controlling signal on controlling chaos
Institute of Scientific and Technical Information of China (English)
李蓉; 祝恒江; 屈支林; 温孝东; 秦光戎; 胡岗
1995-01-01
A model of double-harmonious circuit for non-feedback control of chaos is introduced. A controlling signal is added to the coefficient for two-order term of the nonlinear differential equation The effect of controlling signal on controlling chaos is studied. By changing the controlling frequency fk and controlling strength Ik, chaos to period-doubling, period-adding and quasi-period state can be controlled. The effect of phase on controlling chaos is also discussed. A breathing phenomenon is observed and its mechanism is explained.
Nonlinear Control of Beam Halo-Chaos in Accelerator-Driven Clean Nuclear Power System
Institute of Scientific and Technical Information of China (English)
FANG JinQing; CHEN GuanRong; ZHOU LiuLai; WENG JiaQiang
2002-01-01
Beam halo-chaos in high-current accelerators has become a key concerned issue because it can cause excessive radioactivity from the accelerators therefore significantly limits their applications in industry, medicine, and national defense. Some general engineering methods for chaos control have been developed in recent years, but they generally are unsuccessful for beam halo-chaos suppression due to many technical constraints. Beam halo-chaos is essentially a spatiotemporal chaotic motion within a high power proton accelerator. In this paper, some efficient nonlinear control methods, including wavelet function feedback control as a special nonlinear control method, are proposed for controlling beam halo-chaos under five kinds of the initial proton beam distributions (i.e., Kapchinsky-Vladimirsky, full Gauss,3-sigma Gauss, water-bag, and parabola distributions) respectively. Particles-in-cell simulations show that after control of beam halo-chaos, the beam halo strength factor is reduced to zero, and other statistical physical quantities of beam halo-chaos are doubly reduced. The methods we developed is very effective for suppression of proton beam halo-chaos in a periodic focusing channel of accelerator. Some potential application of the beam halo-chaos control in experiments is finally pointed out.
Chaos analysis and chaotic EMI suppression of DC-DC converters
Zhang, Bo
2014-01-01
Introduces chaos theory, its analytical methods and the means to apply chaos to the switching power supply design DC-DC converters are typical switching systems which have plenty of nonlinear behaviors, such as bifurcation and chaos. The nonlinear behaviors of DC-DC converters have been studied heavily over the past 20 years, yet researchers are still unsure of the practical application of bifurcations and chaos in switching converters. The electromagnetic interference (EMI), which resulted from the high rates of changes of voltage and current, has become a major design criterion in DC-DC co
Obaid, Hafiz Muhammad; Khawar Islam, Muhammad; Obaid Ullah, Muhammad
2016-08-01
Broadband chaos can be generated by beating two wavelengths in a hybrid arrangement of Fabry-Perot (FP) Laser and Fiber ring cavity by injecting dual wavelengths. The bandwidth of generated chaos can be controlled by detuning different modes of FP Laser for beating. The bandwidth of generated chaos increased to many folds depending upon the injected strength and wavelength spacing matched to FP laser modes. The bandwidth enhancement in different simulation experiments conducted is optimized by varying different parameters of FP laser and cavity. The waveforms are analyzed and Lyapunov exponents are calculated in order to validate the existence of high bandwidth non-pulsating chaos.
Study on chaos in short circuit gas metal arc welding process
Institute of Scientific and Technical Information of China (English)
Lü Xiaoqing; Cao Biao; Zeng Min; Wang Zhenmin; Huang Shisheng
2007-01-01
Based on the chaos theory, an idea is put forward to analyze the short circuit Gas Metal Arc Welding (GMAW-S) process. The theory of phase space reconstruction and related algorithms such as mutual information and so on, are applied to analyze the chaos of the GMAW-S process. The largest Lyapunov exponents of some current time series are calculated, and the results indicate that chaos exists in the GMAW-S process. The research of the chaos in the GMAW-S process can be help to get new knowledge of the process.
What are intrinsic motivations? A biological perspective
Baldassarre G.
2011-01-01
The concept of "intrinsic motivation", initially proposed and developed within psychology, is gaining an increasing attention within cognitive sciences for its potential to produce open-ended learning machines and robots. However, a clear definition of the phenomenon is not yet available. This theoretical paper aims to clarify what intrinsic motivations are from a biological perspective. To this purpose, it first shows how intrinsic motivations can be defined contrasting them to extrinsic mot...
Full Amalgamation Classes with Intrinsic Transcendentals
Brody, Justin
2015-01-01
We develop some basic results about full amalgamation classes with intrinsic trascendentals. These classes have generics whose models may have finite subsets whose intrinsic closure is not contained in its algebraic closure. We will show that under fairly natural conditions the generic will have an essentially undecidable theory, but we will also exhibit strictly superstable and strictly simple examples. Separating types over a model into those that are intrinsic and those that are extrinsic,...
Chaos in Compact Binaries with Frequency Map Analysis
Institute of Scientific and Technical Information of China (English)
Yi Xie; Tian-Yi Huang
2006-01-01
The dynamics of compact binaries is very complicated because of spin-orbit coupling and spin-spin coupling. With Laskar's frequency map analysis (FMA) and frequency diffusion as an indicator, we found that misalignment of the spins and orbital angular momentum has a great effect on the dynamics, and for systems with different mass ratios β≡ m2/m1 chaos occurs at different spin-orbit configurations. For equal-mass binaries (β = 1), chaos occurs when the spins nearly cancel each other out. For some other systems (for exampleβ～1/2), the binaries are irregular, even chaotic, when the spins are perpendicular to the orbital angular momentum. For the case where gravitational radiation is taken into account, we give an analytic estimation for the frequency diffusion based on the decay of the orbit, which is roughly consistent with our simulations. This means the FMA is not suitable as a chaos indicator for weak chaotic cases with dissipative terms.
Structured chaos in a devil's staircase of the Josephson junction
Shukrinov, Yu. M.; Botha, A. E.; Medvedeva, S. Yu.; Kolahchi, M. R.; Irie, A.
2014-09-01
The phase dynamics of Josephson junctions (JJs) under external electromagnetic radiation is studied through numerical simulations. Current-voltage characteristics, Lyapunov exponents, and Poincaré sections are analyzed in detail. It is found that the subharmonic Shapiro steps at certain parameters are separated by structured chaotic windows. By performing a linear regression on the linear part of the data, a fractal dimension of D = 0.868 is obtained, with an uncertainty of ±0.012. The chaotic regions exhibit scaling similarity, and it is shown that the devil's staircase of the system can form a backbone that unifies and explains the highly correlated and structured chaotic behavior. These features suggest a system possessing multiple complete devil's staircases. The onset of chaos for subharmonic steps occurs through the Feigenbaum period doubling scenario. Universality in the sequence of periodic windows is also demonstrated. Finally, the influence of the radiation and JJ parameters on the structured chaos is investigated, and it is concluded that the structured chaos is a stable formation over a wide range of parameter values.
Understanding of Arab Spring with Chaos Theory - Uprising or Revolution
Açıkalın, Şuay Nilhan; Bölücek, Cemal Alpgiray
`Arab Spring' can be considered as one of the most remarkable events in the history of world politics. On December 18, 2010, a Tunisian young protestor burned himself in a public square of the city. This event triggered probably one of the most chaotic and long term uprisings in the Middle East. From the day of its initiation until the present, `Arab Spring' in the Middle East created unstable political situation and several uprisings. In this chapter, we will first give general information about chaos theory, and then we will examine the `butterfly effect' created by the Tunisian young protestor and process of Arab Spring in the Middle East regarding its extend and form in those countries within the framework of chaos theory. For the first part of this chapter, the spark created by the Tunisian young protestor and its effects can be analyzed under `butterfly effect' perspective within chaos theory, arguing whether the events followed each other consecutively or randomly. The question is whether the incidents following each other have reasonable links of causality to one another, or the events defining the phenomena known as `Arab Spring' have no predictable reasons and outcomes regardless of the regional, social and political differences. The events caused the collapse of the regimes in Tunisia, Egypt and Libya; they had very serious outcomes.
Chaos, creativity, and substance abuse: the nonlinear dynamics of choice.
Zausner, Tobi
2011-04-01
Artists create their work in conditions of disequilibrium, states of creative chaos that may appear turbulent but are capable of bringing forth new order. By absorbing information from the environment and discharging it negentropically as new work, artists can be modeled as dissipative systems. A characteristic of chaotic systems is a heightened sensitivity to stimuli, which can generate either positive experiences or negative ones that can lead some artists to substance abuse and misguided searches for a creative chaos. Alcohol and drug use along with inadequately addressed co-occurring emotional disorders interfere with artists' quest for the nonlinearity of creativity. Instead, metaphorically modeled by a limit cycle of addiction and then a spiral to disorder, the joys of a creative chaos become an elusive chimera for them rather than a fulfilling experience. Untreated mental illness and addiction to substances have shortened the lives of artists such as Vincent Van Gogh, Frida Kahlo, Henri de Toulouse-Lautrec, and Jackson Pollock, all of whom committed suicide. In contrast Edvard Munch and John Callahan, who chose to address their emotional problems and substance abuse, continued to live and remain creative. Choosing to access previously avoided moments of pain can activate the nonlinear power of self-transformation.
Heading stabilization and anti-rollover for Chaos
Berkemeier, Matthew; Poulson, Eric; King, Sidney L.
2007-04-01
Chaos is a 2-man-portable tele-operated vehicle designed for crossing rugged terrain. Chaos is capable of crossing large piles of cinder blocks, picnic tables, and steep hills of loose soil. These feats are accomplished through use of 4 independent track arms, each of which can be articulated at an arbitrary angle and driven at an arbitrary speed. These make the vehicle extremely capable but also demand significant skill on the part of the user. It is therefore desirable to automate the arm angles and track speeds to ease operator burden. This paper reports on preliminary efforts to implement 2 intelligent behaviors along these lines. The first involves heading stabilization: A gyroscope is used to sense yaw and yaw rate, and these are compared with the operators commands. Deviations are then used to automatically correct the heading. This is useful when Chaos is climbing stairs or other bumpy terrain, which can cause the vehicle to veer off in unwanted directions. We call the other behavior anti-rollover. In this case, the output of a gyroscope is monitored to detect if roll or pitch thresholds are exceeded. When they are, the track arms are automatically positioned to stabilize the vehicle and keep it right side up. Experimental results for both algorithms are included.
Lambda and the edge of chaos in recurrent neural networks.
Seifter, Jared; Reggia, James A
2015-01-01
The idea that there is an edge of chaos, a region in the space of dynamical systems having special meaning for complex living entities, has a long history in artificial life. The significance of this region was first emphasized in cellular automata models when a single simple measure, λCA, identified it as a transitional region between order and chaos. Here we introduce a parameter λNN that is inspired by λCA but is defined for recurrent neural networks. We show through a series of systematic computational experiments that λNN generally orders the dynamical behaviors of randomly connected/weighted recurrent neural networks in the same way that λCA does for cellular automata. By extending this ordering to larger values of λNN than has typically been done with λCA and cellular automata, we find that a second edge-of-chaos region exists on the opposite side of the chaotic region. These basic results are found to hold under different assumptions about network connectivity, but vary substantially in their details. The results show that the basic concept underlying the lambda parameter can usefully be extended to other types of complex dynamical systems than just cellular automata.
Controlling chaos in balanced neural circuits with input spike trains
Engelken, Rainer; Wolf, Fred
The cerebral cortex can be seen as a system of neural circuits driving each other with spike trains. Here we study how the statistics of these spike trains affects chaos in balanced target circuits.Earlier studies of chaos in balanced neural circuits either used a fixed input [van Vreeswijk, Sompolinsky 1996, Monteforte, Wolf 2010] or white noise [Lajoie et al. 2014]. We study dynamical stability of balanced networks driven by input spike trains with variable statistics. The analytically obtained Jacobian enables us to calculate the complete Lyapunov spectrum. We solved the dynamics in event-based simulations and calculated Lyapunov spectra, entropy production rate and attractor dimension. We vary correlations, irregularity, coupling strength and spike rate of the input and action potential onset rapidness of recurrent neurons.We generally find a suppression of chaos by input spike trains. This is strengthened by bursty and correlated input spike trains and increased action potential onset rapidness. We find a link between response reliability and the Lyapunov spectrum. Our study extends findings in chaotic rate models [Molgedey et al. 1992] to spiking neuron models and opens a novel avenue to study the role of projections in shaping the dynamics of large neural circuits.
Urban chaos and replacement dynamics in nature and society
Chen, Yanguang
2014-11-01
Replacements resulting from competition are ubiquitous phenomena in both nature and society. The evolution of a self-organized system is always a physical process substituting one type of components for another type of components. A logistic model of replacement dynamics has been proposed in terms of technical innovation and urbanization, but it fails to arouse widespread attention in the academia. This paper is devoted to laying the foundations of general replacement principle by using analogy and induction. The empirical base of this study is urban replacement, including urbanization and urban growth. The sigmoid functions can be employed to model various processes of replacement. Many mathematical methods such as allometric scaling and head/tail breaks can be applied to analyzing the processes and patterns of replacement. Among varied sigmoid functions, the logistic function is the basic and the simplest model of replacement dynamics. A new finding is that replacement can be associated with chaos in a nonlinear system, e.g., urban chaos is just a part of replacement dynamics. The aim of developing replacement theory is at understanding complex interaction and conversion. This theory provides a new way of looking at urbanization, technological innovation and diffusion, Volterra-Lotka’s predator-prey interaction, man-land relation, and dynastic changes resulting from peasant uprising, and all that. Especially, the periodic oscillations and chaos of replacement dynamics can be used to explain and predict the catastrophic occurrences in the physical and human systems.
Application of Chaos Theory in Trucks' Overloading Enforcement
Directory of Open Access Journals (Sweden)
Abbas Mahmoudabadi
2013-01-01
Full Text Available Trucks' overloading is considered as one of the most substantial concerns in road transport due to a possible road surface damage, as well as, are less reliable performance of trucks' braking system. Sufficient human resource and adequate time scheduling are to be planned for surveying trucks' overloading; hence, it seems required to prepare an all-around model to be able to predict the number of overloaded vehicles. In the present research work, the concept of chaos theory has been utilized to predict the ratio of trucks which might be guessed overloaded. The largest Lyapunov exponent is utilized to determine the presence of chaos using experimental data and concluded that the ratio of overloaded trucks reflects chaotic behavior. The prediction based on chaos theory is compared with the results of simple smoothing and moving average methods according to the well-known criterion of mean square errors. The results have also revealed that the chaotic prediction model would act more capably comparing the analogous methods including simple smoothing and moving average to predict the ratio of passing trucks to be possibly overloaded.
Design of intrinsically safe power supply
Institute of Scientific and Technical Information of China (English)
LI Rui-jin; JIN Lin
2012-01-01
Aiming to make a high power direct current supply safely used in coal mine production,this paper made a deep research on characteristics of intrinsically safe power supply,using the mathematical model established according to coal mine intrinsic safety standards.It provides theory support for the application of high power intrinsically safe power supply.The released energy of output short circuit of switch power supply,and the close related factors that influence the biggest output short-circuit spark discharge energy are the theoretical basis of the power supply.It is shown how to make a high power intrinsically safe power supply using the calculated values in the mathematical model,and take values from intrinsically safe requirements parameters scope,then this theoretical calculation value can be developed as the ultimate basis for research of the power supply.It gets the identification method of intrinsically safe from mathematics model of intrinsically safe power supply characteristics study,which solves the problem of theory and application of designing different power intrinsically safe power supply,and designs a kind of high power intrinsically safe power supply through this method.
International Nuclear Information System (INIS)
The aim of this paper is to review the classical limit of Quantum Mechanics and to precise the well known threat of chaos (and fundamental graininess) to the correspondence principle. We will introduce a formalism for this classical limit that allows us to find the surfaces defined by the constants of the motion in phase space. Then in the integrable case we will find the classical trajectories, and in the non-integrable one the fact that regular initial cells become “amoeboid-like”. This deformations and their consequences can be considered as a threat to the correspondence principle unless we take into account the characteristic timescales of quantum chaos. Essentially we present an analysis of the problem similar to the one of Omnès (1994,1999), but with a simpler mathematical structure
Black Sea Abyss: Chaos and Writing in Ancient Mesopotamia
Directory of Open Access Journals (Sweden)
David Prescott-Steed
2008-07-01
Full Text Available This discussion explores the intersection of chaos and writing in the context of the Eridu Genesis, a Sumerian cuneiform text dating back to the 18th century BC and containing three narratives : the Creation of humankind, the building of cities, and a flood myth. Researchers analyze the extent to which conceptions of chaos, found in this text, recount the Black Sea deluge that scientists agree occurred around 5500 BC. Having authored the world’s oldest known historical texts, Sumerian writings simultaneously mark the beginning of written literature and the birth pangs of chaos ‘in’ writing. Thus the Eridu Genesis, as the archetype for these narratives, deserves critical attention when affording ‘writing and chaos’ a historical context. The question of whether or not the Black Sea flood continues to underpin late modern notions of chaos remains open. However, this geo-cultural reading shows that writing about chaos can provide insight into the human condition, by giving expression to what it means for a civilization to exist in an unpredictable world.Esta discusión examina la intersección del caos y la escritura en el contexto del Eridu Genesis, un texto cuneiforme Sumerio que data del siglo XVlll AC y que contiene tres narraciones : la creación de la humanidad, la construcción de las ciudades, y un mito sobre una inundación. Los investigadores consideran hasta qué punto las concepciones sobre el caos halladas en este texto, hablan sobre el diluvio del Mar Negro, que los científicos están de acuerdo en afirmar que ocurrió aproximadamente 5500 AC. Las escrituras Sumerias son los más antiguos textos históricos conocidos del mundo, y marcan simultáneamente el principio de la literatura escrita y el nacimiento del caos en la escritura. Así, el Génesis de Eridu, como arquetipo de estas narrativas, merece una atención crítica cuando mencionamos ‘escritura y caos’, en un contexto histórico. La pregunta de si el diluvio
Intrinsically photosensitive retinal ganglion cells
Institute of Scientific and Technical Information of China (English)
Gary; E.PICKARD; Patricia; J.SOLLARS
2010-01-01
A new mammalian photoreceptor was recently discovered to reside in the ganglion cell layer of the inner retina.These intrinsically photosensitive retinal ganglion cells(ipRGCs) express a photopigment,melanopsin,that confers upon them the ability to respond to light in the absence of all rod and cone photoreceptor input.Although relatively few in number,ipRGCs extend their dendrites across large expanses of the retina making them ideally suited to function as irradiance detectors to assess changes in ambient light levels.Phototransduction in ipRGCs appears to be mediated by transient receptor potential channels more closely resembling the phototransduction cascade of invertebrate rather than vertebrate photoreceptors.ipRGCs convey irradiance information centrally via the optic nerve to influence several functions.ipRGCs are the primary retinal input to the hypothalamic suprachiasmatic nucleus(SCN),a circadian oscillator and biological clock,and this input entrains the SCN to the day/night cycle.ipRGCs contribute irradiance signals that regulate pupil size and they also provide signals that interface with the autonomic nervous system to regulate rhythmic gene activity in major organs of the body.ipRGCs also provide excitatory drive to dopaminergic amacrine cells in the retina,providing a novel basis for the restructuring of retinal circuits by light.Here we review the ground-breaking discoveries,current progress and directions for future investigation.
Protein intrinsic disorder in plants
Directory of Open Access Journals (Sweden)
Florencio ePazos
2013-09-01
Full Text Available To some extent contradicting the classical paradigm of the relationship between protein 3D structure and function, now it is clear that large portions of the proteomes, especially in higher organisms, lack a fixed structure and still perform very important functions. Proteins completely or partially unstructured in their native (functional form are involved in key cellular processes underlain by complex networks of protein interactions. The intrinsic conformational flexibility of these disordered proteins allows them to bind multiple partners in transient interactions of high specificity and low affinity. In concordance, in plants this type of proteins has been found in processes requiring these complex and versatile interaction networks. These include transcription factor networks, where disordered proteins act as integrators of different signals or link different transcription factor subnetworks due to their ability to interact (in many cases simultaneously with different partners. Similarly, they also serve as signal integrators in signalling cascades, such as those related to response to external stimuli. Disordered proteins have also been found in plants in many stress-response processes, acting as protein chaperones or protecting other cellular components and structures. In plants, it is especially important to have complex and versatile networks able to quickly and efficiently respond to changing environmental conditions since these organisms can not escape and have no other choice than adapting to them. Consequently, protein disorder can play an especially important role in plants, providing them with a fast mechanism to obtain complex, interconnected and versatile molecular networks.
Expressing intrinsic volumes as rotational integrals
DEFF Research Database (Denmark)
Auneau, Jeremy Michel; Jensen, Eva Bjørn Vedel
2010-01-01
A new rotational formula of Crofton type is derived for intrinsic volumes of a compact subset of positive reach. The formula provides a functional defined on the section of X with a j-dimensional linear subspace with rotational average equal to the intrinsic volumes of X. Simplified forms of the...... functional are derived in special cases....
Intrinsic bioremediation of landfills interim report
Energy Technology Data Exchange (ETDEWEB)
Brigmon, R.L. [Westinghouse Savannah River Company, Aiken, SC (United States); Fliermans, C.B.
1997-07-14
Intrinsic bioremediation is a risk management option that relies on natural biological and physical processes to contain the spread of contamination from a source. Evidence is presented in this report that intrinsic bioremediation is occurring at the Sanitary Landfill is fundamental to support incorportion into a Corrective Action Plan (CAP).
Intrinsic bioremediation of landfills interim report
International Nuclear Information System (INIS)
Intrinsic bioremediation is a risk management option that relies on natural biological and physical processes to contain the spread of contamination from a source. Evidence is presented in this report that intrinsic bioremediation is occurring at the Sanitary Landfill is fundamental to support incorportion into a Corrective Action Plan (CAP)
Keaten, James A.
This paper offers a model that integrates chaos theory and cybernetics, which can be used to describe the structure of decision making within small groups. The paper begins with an overview of cybernetics and chaos. Definitional characteristics of cybernetics are reviewed along with salient constructs, such as goal-seeking, feedback, feedback…
CHAOS: User-driven Development of a Metadata Scheme for Radio Broadcast Archives
DEFF Research Database (Denmark)
Lykke, Marianne; Bogers, Toine; Larsen, Birger;
2013-01-01
CHAOS (Cultural Heritage Archive Open System) is a digital platform for Danish radio broadcasts. Radio broadcasts are an important and vibrant part of our cultural heritage, but providing efficient and effective access to such archives is challenging for lack of a solid digital infrastructure. Th...... of the multi-tiered metadata scheme used in CHAOS....
Institute of Scientific and Technical Information of China (English)
GAO Ji-Hua; ZHENG Zhi-Gang; TANG Jiao-Ning; PENG Jian-Hua
2003-01-01
A model of two-dimensional coupled complex Ginzburg-Landau oscillators driven by a rectificative feedbackcontroller is used to study controlling spatiotemporal chaos without gradient force items. By properly selecting the signalinjecting position with considering the maximum gap between signals and targets, and adjusting the control time interval,we have finally obtained the efficient chaos control via numerical simulations.
Institute of Scientific and Technical Information of China (English)
GAOJi-Hua; ZHENGZhi-Gang; TANGJiao-Ning; PENGJian-Hua
2003-01-01
A model of two-dimensional coupled complex Ginzburg-Landau oscillators driven by a rectificative feedback controller is used to study controlling spatiotemporal chaos without gradient force items. By properly selecting the signal injecting position with considering the maximum gap between signals and targets, and adjusting the control time interval,we have finally obtained the efficient chaos control via numerical simulations.
Controlling Strong Chaos by Adaptive Coupling Method in the Perturbed Cat Map
Institute of Scientific and Technical Information of China (English)
许海波; 王光瑞; 陈式刚
2001-01-01
The method for controlling Hamiltonian chaos by adaptive integrable mode coupling is extended to controlling strong chaos by adaptive integrable and near-integrable mode coupling. We illustrate this method with a highly chaotic system, the perturbed cat map. All orbits can be effectively controlled to the periodic or quasiperiodic orbits. The method is robust against the presence of weak external noise.
Gilstrap, Donald L.
2013-01-01
In addition to qualitative methods presented in chaos and complexity theories in educational research, this article addresses quantitative methods that may show potential for future research studies. Although much in the social and behavioral sciences literature has focused on computer simulations, this article explores current chaos and…
Invisible grazings and dangerous bifurcations in impacting systems: The problem of narrow-band chaos
Banerjee, Soumitro; Ing, James; Pavlovskaia, Ekaterina; Wiercigroch, Marian; Reddy, Ramesh K.
2009-03-01
We discovered a narrow band of chaos close to the grazing condition for a simple soft impact oscillator. The phenomenon was observed experimentally for a range of system parameters. Through numerical stability analysis, we argue that this abrupt onset to chaos is caused by a dangerous bifurcation in which two unstable period-3 orbits, created at “invisible” grazings, take part.
Finite-Time Chaos Suppression of Permanent Magnet Synchronous Motor Systems
Directory of Open Access Journals (Sweden)
Yi-You Hou
2014-04-01
Full Text Available This paper considers the problem of the chaos suppression for the Permanent Magnet Synchronous Motor (PMSM system via the finite-time control. Based on Lyapunov stability theory and the finite-time controller are developed such that the chaos behaviors of PMSM system can be suppressed. The effectiveness and accuracy of the proposed methods are shown in numerical simulations.
DTU candidate field models for IGRF-12 and the CHAOS-5 geomagnetic field model
DEFF Research Database (Denmark)
Finlay, Chris; Olsen, Nils; Tøffner-Clausen, Lars
2015-01-01
We present DTU’s candidate field models for IGRF-12 and the parent field model from which they were derived,CHAOS-5. Ten months of magnetic field observations from ESA’s Swarm mission, together with up-to-date ground observatory monthly means, were used to supplement the data sources previously...... used to construct CHAOS-4. Theinternal field part of CHAOS-5, from which our IGRF-12 candidate models were extracted, is time-dependent up to spherical harmonic degree 20 and involves sixth-order splines with a 0.5 year knot spacing. In CHAOS-5, comparedwith CHAOS-4, we update only the low......-degree internal field model (degrees 1 to 24) and the associated external field model. The high-degree internal field (degrees 25 to 90) is taken from the same model CHAOS-4h, based onlow-altitude CHAMP data, which was used in CHAOS-4.We find that CHAOS-5 is able to consistently fit magnetic field data from six...
Suppression of beam halo-chaos using nonlinear feedback discrete control method
Fang Jin Qing; Chen Guan Rong; Luo Xiao Shu; Weng Jia Qiang
2002-01-01
Based on nonlinear feedback control method, wavelet-based feedback controller as a especial nonlinear feedback function is designed for controlling beam halo-chaos in high-current accelerators of driven clean nuclear power system. PIC simulations show that suppression of beam halo-chaos are realized effectively after discrete control of wavelet-based feed-back is applied to five kinds of the initial proton beam distributions, respectively. The beam halo strength factor is quickly reduced to zero, and other statistical physical quantities of beam halo-chaos are more than doubly reduced. These performed PIC simulation results demonstrate that the developed methods are very effective for control of beam halo-chaos. Potential application of the beam halo-chaos control methods is discussed finally
A unified theory of chaos linking nonlinear dynamics and statistical physics
Poon, Chi-Sang; Wu, Guo-Qiang
2010-01-01
A fundamental issue in nonlinear dynamics and statistical physics is how to distinguish chaotic from stochastic fluctuations in short experimental recordings. This dilemma underlies many complex systems models from stochastic gene expression or stock exchange to quantum chaos. Traditionally, deterministic chaos is characterized by "sensitive dependence on initial conditions" as indicated by a positive Lyapunov exponent. However, ambiguity arises when applying this criterion to real-world data that are corrupted by measurement noise or perturbed nonautonomously by exogenous deterministic or stochastic inputs. Here, we show that a positive Lyapunov exponent is surprisingly neither necessary nor sufficient proof of deterministic chaos, and that a nonlinear dynamical system under deterministic or stochastic forcing may exhibit multiple forms of nonautonomous chaos assessable by a noise titration assay. These findings lay the foundation for reliable analysis of low-dimensional chaos for complex systems modeling an...
Chaos and Cosmos on The Streets of Gostivar
Directory of Open Access Journals (Sweden)
Barbara Turk Niskač
2009-12-01
Full Text Available This paper focuses on the streets in Gostivar, Macedonia, and how its young Albanian and Macedonian inhabitants perceive them. I am interested in how the ethnic division in the town influences perceptions and behavior. Macedonian girls are exposed to verbal sexual advances and harassment by Albanians, whereas boys are exposed to occasional fights. On the other hand, among Albanian youth the fear of the Other is not as present as among the Macedonians. In seeking the reasons for this situation, I deal with the concepts of chaos and cosmos, social control, gossip, cultural differences, kinship, and patriarchy. The streets are one of the spaces where identification takes place, and gender and ethnic identities are related to interactions in the streets. By defining boundaries in space, people create and maintain the boundaries between “us” and “them.” Identities are built in the process of interaction with others. The process of identification is connected to defining the similarities and differences in relation to “us.” People place themselves in the center, in the sphere of the cosmos, which they relate to home, the known, order, safety, and cleanliness. They place the Other in the sphere of chaos because the Other represents the distant, the foreign, the unknown, disorder, danger, and uncleanness. Public opinion is important in maintaining identities and boundaries. Girls in particular must safeguard their honor, which is constantly under surveillance. Identification is maintained by avoiding the space of the Other. Individuals avoid it in order to maintain their good name in the eyes of their group. Through the constant maintenance of the identities and boundaries between “us” and “them,” or between cosmos and chaos, one can trace the fear of losing one’s own identity. Each side is afraid that they might become like “them.”
A Case for Hydrothermal Gray Hematite in Aram Chaos
Catling, D. C.; Moore, J. M.
2003-01-01
The Thermal Emission Spectrometer (TES) on Mars Global Surveyor has detected deposits of coarsegrained, gray crystalline hematite in Sinus Meridiani, Aram Chaos, and Vallis Marineris [1]. Detailed features in the hematite spectral signature of the Sinus Meridiani region show that the spectrum is consistent with emission dominated by crystal c-faces of hematite, implying that the hematite is specular [2]. Gray specular hematite (also known as specularite ) is a particular gray crystalline form that has intergrown, hexagonal plates with a silvery metallic luster. We believe that the key to the origin of specularite is that it requires crystallization at temperatures in excess of about 100 C. In reviewing the occurrence of gray hematite on Earth, we find no exceptions to this warm temperature requirement [3]. Thermal crystallization on Mars could occur (1) as diagenesis at a depth of a few kilometers of sediments originally formed in lowtemperature waters, or (2) as direct precipitation from hydrothermal solution. Aram Chaos has unique chaotic terrain that offers more clues to the formation of the hematite than the relatively featureless flat terrain (as seen from orbit) of Sinus Meridiani. Aram Chaos provides the opportunity to look at a combination of TES data, Mars Orbiter Camera images, and Mars Orbiter Laser Altimeter (MOLA) topography. This combination of data suggests that high concentrations of hematite were formed in planar strata and have since been exposed by erosion of an overlying light-toned, caprock. Lesser concentrations of hematite are found adjacent to these strata at lower elevations, which we interpret as perhaps a lag deposit. The topography and the collapsed nature of the chaotic terrain favor a hydrothermally charged aquifer as the original setting where the hematite formed. An alternative sedimentary origin requires post-depositional burial to a depth of 3-5 km to induce thermally driven recrystallization of fine-grained iron oxides to coarse
Making sense of social media communications with chaos theory
DEFF Research Database (Denmark)
Gyimóthy, Szilvia; Larson, Mia
-organising, as the pattern of behaviour in the system evolves or emerges from the local interaction and adjustments between the agents. Instead of channelled flow of information, the nodes of this network transmit information in all directions simultaneously. Our goal is model the patterns of sense......: Routledge. Russell, R. & Faulkner, B. (2004). Entrepreneurship, Chaos and the Tourism Area Lifecycle. Annals of Tourism Research, 31(3), 556-579. Stacey, R.D. (2003). Strategic Management and Organisational Dynamics: The Challenge of Complexity. Harlow: FT/Prentice Hall. Wheatley, M.J. (1993). Leadership...
Quantum Secure Direct Communication Based on Chaos with Authentication
Huang, Dazu; Chen, Zhigang; Guo, Ying; Lee, Moon Ho
2007-12-01
A quantum secure direct communication protocol based on chaos is proposed with authentication. It has an advantage over distributing the secret message directly and verifying the communicators’ identities with the assistance of a trusted center. To ensure the security of the secret message and the process of verification, the initial order of the travel particles is disturbed according to a chaotic sequence generated secretly via the general Arnold map. Security analysis demonstrates that the present scheme is secure against several attack strategies, such as the man-in-the-middle attack and Trojan horse attack.
Chaos Transfer in Fluidized Beds Accompanied with Biomass Pyrolysis
Institute of Scientific and Technical Information of China (English)
唐松涛; 李定凯; 吕子安; 沈幼庭
2003-01-01
Experiments of biomass pyrolysis were carried out in a fiuidized bed, and dynamic signals of pressure and temperature were recorded. Correlation dimension was employed to characterize the chaotic behavior of pressure and temperature signals. Both pressure and temperature signals exhibit chaotic behavior, and the chaotic behavior of temperature signals is always weaker than that of pressure signals. Chaos transfer theory was advanced to explain the above phenomena. The discussion on the algorithm of the correlation dimension shows that the distance definition based on rhombic neighborhood is a better choice than the traditional one based on spherical neighborhood. The former provides a satisfactory result in a much shorter time.
Evidence for Lorenz-type chaos in a laser
Weiss, C. O.; Brock, J.
1986-12-01
Observations of the dynamics of a single-mode, traveling-wave laser under bad-cavity conditions are reported. The sequence of instabilities occurring on resonator tuning corresponds in detail to the transition to chaos of the logistic equation. Period-doubling cascade, reverse ('noisy') cascade, and the regular period-3 and -5 windows in the chaotic range are observed. At presumably homogeneous broadening conditions the transition from CW to chaotic emission is abrupt on pump variation. All of the observed features including instability pump thresholds and characteristics of the chaotic laser pulses agree with predictions of the Lorenz equations.
Dynamic Feedback Controlling Chaos in Current-Mode Boost Converter
Institute of Scientific and Technical Information of China (English)
LU Wei-Guo; ZHOU Luo-Wei; LUO Quan-Ming
2007-01-01
A method for the control of chaos in the current-mode boost converter is presented by using the first-order dynamic feedback control. The feedback part consists of a resistance and a capacitance in series. The system to be controlled is treated as a third-order model, and then the discrete mapping model is obtained by using the data-sampling method. By analysing the position of the maximum norm eigenvalue, the stable range of feedback gain is ascertained out and its optimization is also carried out. Finally, the results of simulation and experiment confirm the correctness of the theoretical analysis and the validity of the proposed means.
Hardware Realization of Chaos Based Symmetric Image Encryption
Barakat, Mohamed L.
2012-06-01
This thesis presents a novel work on hardware realization of symmetric image encryption utilizing chaos based continuous systems as pseudo random number generators. Digital implementation of chaotic systems results in serious degradations in the dynamics of the system. Such defects are illuminated through a new technique of generalized post proceeding with very low hardware cost. The thesis further discusses two encryption algorithms designed and implemented as a block cipher and a stream cipher. The security of both systems is thoroughly analyzed and the performance is compared with other reported systems showing a superior results. Both systems are realized on Xilinx Vetrix-4 FPGA with a hardware and throughput performance surpassing known encryption systems.
Random number generation based on digital differential chaos
Zidan, Mohammed A.
2012-07-29
In this paper, we present a fully digital differential chaos based random number generator. The output of the digital circuit is proved to be chaotic by calculating the output time series maximum Lyapunov exponent. We introduce a new post processing technique to improve the distribution and statistical properties of the generated data. The post-processed output passes the NIST Sp. 800-22 statistical tests. The system is written in Verilog VHDL and realized on Xilinx Virtex® FPGA. The generator can fit into a very small area and have a maximum throughput of 2.1 Gb/s.
Quantum chaos, thermalization and dissipation in nuclear systems
Indian Academy of Sciences (India)
Sudhir R Jain
2001-08-01
Nuclei have complex energy-level sequence with statistical properties in agreement with canonical random matrix theory. This agreement appears when the one-particle one-hole states are mixed completely with two-particle two-hole states. In the transition, there is a new universality which we present here, bringing about a relation between dynamics and statistics. We summarize also the role of chaos in thermalization and dissipation in isolated systems like nuclei. The methods used to bring forth this understanding emerge from random matrix theory, semiclassical physics, and the theory of dynamical systems.
Improved Adaptive LSB Steganography Based on Chaos and Genetic Algorithm
Directory of Open Access Journals (Sweden)
Yu Lifang
2010-01-01
Full Text Available We propose a novel steganographic method in JPEG images with high performance. Firstly, we propose improved adaptive LSB steganography, which can achieve high capacity while preserving the first-order statistics. Secondly, in order to minimize visual degradation of the stego image, we shuffle bits-order of the message based on chaos whose parameters are selected by the genetic algorithm. Shuffling message's bits-order provides us with a new way to improve the performance of steganography. Experimental results show that our method outperforms classical steganographic methods in image quality, while preserving characteristics of histogram and providing high capacity.
Chaos and Stochastic Models in Physics: Ontic and Epistemic Aspects
Caprara, Sergio
2016-01-01
There is a persistent confusion about determinism and predictability. In spite of the opinions of some eminent philosophers (e.g., Popper), it is possible to understand that the two concepts are completely unrelated. In few words we can say that determinism is ontic and has to do with how Nature behaves, while predictability is epistemic and is related to what the human beings are able to compute. An analysis of the Lyapunov exponents and the Kolmogorov-Sinai entropy shows how deterministic chaos, although with an epistemic character, is non subjective at all. This should clarify the role and content of stochastic models in the description of the physical world.
FFT Bifurcation Analysis of Routes to Chaos via Quasiperiodic Solutions
Directory of Open Access Journals (Sweden)
L. Borkowski
2015-01-01
Full Text Available The dynamics of a ring of seven unidirectionally coupled nonlinear Duffing oscillators is studied. We show that the FFT analysis presented in form of a bifurcation graph, that is, frequency distribution versus a control parameter, can provide a valuable and helpful complement to the corresponding typical bifurcation diagram and the course of Lyapunov exponents, especially in context of detailed identification of the observed attractors. As an example, bifurcation analysis of routes to chaos via 2-frequency and 3-frequency quasiperiodicity is demonstrated.
New Iris Localization Method Based on Chaos Genetic Algorithm
Institute of Scientific and Technical Information of China (English)
Jia Dongli; Muhammad Khurram Khan; Zhang Jiashu
2005-01-01
This paper present a new method based on Chaos Genetic Algorithm (CGA) to localize the human iris in a given image. First, the iris image is preprocessed to estimate the range of the iris localization, and then CGA is used to extract the boundary of the iris. Simulation results show that the proposed algorithms is efficient and robust, and can achieve sub pixel precision. Because Genetic Algorithms (GAs) can search in a large space, the algorithm does not need accurate estimation of iris center for subsequent localization, and hence can lower the requirement for original iris image processing. On this point, the present localization algirithm is superior to Daugmans algorithm.
Phase diffusion in localized spatio-temporal amplitude chaos
Granzow, G D; Granzow, Glen D; Riecke, Hermann
1996-01-01
We present numerical simulations of coupled Ginzburg-Landau equations describing parametrically excited waves which reveal persistent dynamics due to the occurrence of phase slips in sequential pairs, with the second phase slip quickly following and negating the first. Of particular interest are solutions where these double phase slips occur irregularly in space and time within a spatially localized region. An effective phase diffusion equation utilizing the long term phase conservation of the solution explains the localization of this new form of amplitude chaos.
Defect Chaos of Oscillating Hexagons in Rotating Convection
Echebarria, B; Echebarria, Blas; Riecke, Hermann
2000-01-01
Using coupled Ginzburg-Landau equations, the dynamics of hexagonal patterns with broken chiral symmetry are investigated, as they appear in rotating non-Boussinesq or surface-tension-driven convection. We find that close to the secondary Hopf bifurcation to oscillating hexagons the dynamics are well described by a single complex Ginzburg-Landau equation (CGLE) coupled to the phases of the hexagonal pattern. At the bandcenter these equations reduce to the usual CGLE and the system exhibits defect chaos. Away from the bandcenter a transition to a frozen vortex state is found.
COPD self-management supportive care: chaos and complexity theory.
Cornforth, Amber
This paper uses the emergent theories of chaos and complexity to explore the self-management supportive care of chronic obstructive pulmonary disease (COPD) patients within the evolving primary care setting. It discusses the concept of self-management support, the complexity of the primary care context and consultations, smoking cessation, and the impact of acute exacerbations and action planning. The author hopes that this paper will enable the acquisition of new insight and better understanding in this clinical area, as well as support meaningful learning and facilitate more thoughtful, effective and high quality patient-centred care within the context of primary care.