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## Hidden Attractors in a Model of a Bubble Contrast Agent Oscillating Near an Elastic Wall

A model describing the dynamics of a spherical gas bubble in a compressible viscous liquid is studied. The bubble is oscillating close to an elastic wall of finite thickness under the influence of an external pressure field which simulates a contrast agent oscillating close to a blood vessel wall. Here we investigate numerically the coexistence of chaotic and periodic attractors in this model. One of the tools applied for seeking coexisting attractors is the perpetual points method. This method can be helpful for localizing coexisting attractors, occurring in various physically realistic ranges of variation of the control parameters. We provide some examples of coexisting attractors to demonstrate the importance of the multistability problem for the applications.

The approaches to the modeling of innovative development of economic systems based on the methodology of nonlinear dynamics are proposed. The generalized nonlinear dynamic models for the analysis of economic development is discussed. The loss of stability of the dynamic mode and the area of deterministic chaos are considered in terms of risk analysis

Main concepts and models of the modern theory of self-organization of complex systems, called also synergetics, are generalized and formulated in the book as principles of a synergetic world view. They are under discussion in the context of philosophical studies of holism, teleology, evolutionism as well as of gestalt-psychology; they are compared with some images from the history of human culture. The original and unfamiliar (to the Western readers) research results of the Moscow synergetic school which has its center at the Keldysh Institute of Applied Mathematics of the Russian Academy of Sciences are expounded in the book. Complicated and paradoxical concepts of synergetics (structure-attractors, bifurcations, blow-up regimes, non-stationary dissipative structures of self-organization, fractals, non-linearity) are translated into an intelligible language and vividly illustrated by materials and examples from various fields of knowledge, starting with the laser thermonuclear fusion and concluding with mysterious phenomena of human psychology and creativity. The style of writing is close to that of popular-science literature. That's why the book might be of interest and is quite comprehensible for students and specialists in the humanities. It is shown that the development of synergetics entails deep changes in the conceptual net through which we comprehend the world. It means a radical shift of paradigm, a conceptual transition from being to becoming, from stability to sustainability, from images of order to chaos generating new ordered evolving structures, from self-maintaining systems to fast evolution through a nonlinear positive feedback, from evolution to co-evolution, reciprocal evolution of different complex systems. The new synergetic way of thinking is evolutionary, nonlinear and holistic. This is a modern stage of development within the traditions of cybernetics and system-structural analysis. However, many elements of the latter have undergone important changes since their appearance.

In this work we discuss complex dynamics arising in a model describing behavior of an encapsulated bubble contrast agent oscillating close to an elastic wall. We demonstrate presence of three coexisting attractors in the system. We propose an efficient numerical procedure based on the continuation method that can be used to locate the area of coexistence of these attractors in the parameters space. We provide area of coexistence of three attractors obtained by means of the proposed procedure.

Some texts written by me together with corresponding member of the Russian Academy of science Sergei P. Kurdyumov (1928-2004) and under his direct ideological influence are collected in the book. These texts are elaborated, systematized, brought together in the book and supplemented with new materials. Sergei P. Kurdyumov were possessed of a deep metaphysical flair and put forward ideas, the matter of which are not fully clear up to now. These are, first of all, the idea of co-evolution and the notion of complex structures developing at different tempos as co-existing tempo-worlds. Owing to developments in the field of nonlinear dynamics and of synergetics, the classical problem of time and the problems of evolutionary holism disclose some new and non-traditional aspects. The matter of new notions of nonlinearity of the course of time in the processes of evolution and coevolution and of nonlinear links between different modi of time – between the past, the present and the future - come to the light in the book. Analyses of four interconnected aspects of the course of processes in open and nonlinear dissipative systems – of evolutionarity, temporality, emergent nature and holism – are carried out. A whole series of paradoxical notions, such as “the influence of the future upon the present”, “the possibility of touch of a remote future in praesenti”, irreversibility and elements of reversibility of the course of time appear in synergetics, non-traditional and nonlinear notion of time being at the heart of all of them. It is shown that the best pictorial view of the nonlinear time is apparently the tree of evolution or the tree of time that represent one of archetypes in the human psyche. This image is widely used in myths and religious doctrines of the world nations (the tree of evolution of languages from some united parent language or the tree of evolution of biological species), the image is often drawn by children, appears in consciousness of a man in his sleep, etc. The synergetics methodology under development is applied to study of cognitive systems. The emergent structures of evolution and of self-organization of the individual consciousness, their spatiotemporal peculiarities, and the complexity of the human Self are considered in detail. The radical changes in the understanding of the problems of time that occur due to synergetics are compared with images of time and with the notions of connection between the past, the present and the future in the history of philosophy and of culture. The obtained methodological inferences are of great importance for a reform of systems of education, for forecasting (for building of scenarios of future development), for effective management activity in the modern globalizing world, for elaboration of methods of stimulation of the creative thinking, for the growth of personality and its adequate building into the social media.

The dynamic approach to understanding of the human consciousness, its cognitive activities and cognitive architecture is one of the most promising approaches in the modern epistemology and cognitive science. The conception of embodied mind is under discussion in the light of nonlinear dynamics and of the idea co-evolution of complex systems developed by the Moscow scientific school. The cognitive architecture of the embodied mind is rather complex: data from senses and products of rational thinking, the verbal and the pictorial, logic and intuition, the analytical and synthetic abilities of perception and of thinking, the local and the global, the analogue and the digital, the archaic and the post-modern are intertwined in it. In the process of cognition, co-evolution of embodied mind as an autopoietic system and its surroundings takes place. The perceptual and mental processes are bound up with the structure of human body. Nonlinear and circular connecting links between the subject of cognition and the world constructed by him can be metaphorically called a nonlinear cobweb of cognition. Cognition is an autopoietic activity because it is directed to the search of elements that are missed; it serves to completing integral structures. According to the theory of blow-up regimes in complex systems elaborated by Sergey P.Kudyumov and his followers, the idea of co-evolution is connected with the concept of tempoworlds. To co-evolve means to start to develop in one and the same tempoworld and to use the possibility – in case of a proper intergation into a whole structure – to accelerate the tempo of evolution. The cognitive activities of the human being can be considered as a movement (active walk) in landscapes of co-evolution when he cognizes and changes environment and is changed himself by the very activities. The similar conclusion can be drawn from Francisco Varela’s conception of enactive cognition.

This proceedings publication is a compilation of selected contributions from the “Third International Conference on the Dynamics of Information Systems” which took place at the University of Florida, Gainesville, February 16–18, 2011. The purpose of this conference was to bring together scientists and engineers from industry, government, and academia in order to exchange new discoveries and results in a broad range of topics relevant to the theory and practice of dynamics of information systems. Dynamics of Information Systems: Mathematical Foundation presents state-of-the art research and is intended for graduate students and researchers interested in some of the most recent discoveries in information theory and dynamical systems. Scientists in other disciplines may also benefit from the applications of new developments to their own area of study.

This article discusses examples of nonlinear models of economic dynamics and possibilities of their research by numerical procedures in MATLAB. Demonstrated specific effects of these models, in particular, the possibility of forming a chaotic behavior

The classical cybernetics in the Norbert Wiener’s tradition is nowadays a part of the mathematical theory of complex systems and nonlinear dynamics. Only in these frameworks, building of structures and patterns in nature and technics can be explained and in computer models simulated. Self-organization and emergence became welldefined concepts and can be transferred to technical systems. In the first part of the article, the foundations of complex systems and of nonlinear dynamics are under review. As an application, the building of structures and patterns in complex cell systems, which are subject of system biology, is considered. In the second part, the application of complex system dynamics to evolution of brain and cognition is explored. The research gives us a prerequisite for development of cognitive and social robots, what the topic of the third part is. Neural network structures are not at all limited to individual organisms and robots. In the fourth part, the cyberphysical systems, by means of which complex self-controlling sociotechnical systems are modeled, are studied. The mathematical theory of complex systems and nonlinear dynamics provides us with foundation for understanding of self-organization and emergence in this field. Finally, the question of ethical and social general conditions for technical constructing of complex self-organizing systems are stated and discussed.

Main concepts and models of the modern theory of self-organization of complex systems, called also synergetics, are generalized and formulated in the book as principles of a synergetic world view. They are under discussion in the context of philosophical studies of holism, teleology, evolutionism as well as of gestalt-psychology; they are compared with some images from the history of human culture. The original and unfamiliar (to the Western readers) research results of the Moscow synergetic school which has its center at the Keldysh Institute of Applied Mathematics of the Russian Academy of Sciences are expounded in the book. The heuristic value of the synergetic models of evolution and self-organization of complex systems in epistemology and cognitive psychology, education and teaching, futures studies, social management activities and systems of global security is shown in the book. The book is addressed to a wide circle of readers: students, teachers, scientists who are specialized in different fields of natural sciences and the humanities as well as to all readers who strive for using recent results of science for reflections and achieving success in their own life.

A model for organizing cargo transportation between two node stations connected by a railway line which contains a certain number of intermediate stations is considered. The movement of cargo is in one direction. Such a situation may occur, for example, if one of the node stations is located in a region which produce raw material for manufacturing industry located in another region, and there is another node station. The organization of freight traﬃc is performed by means of a number of technologies. These technologies determine the rules for taking on cargo at the initial node station, the rules of interaction between neighboring stations, as well as the rule of distribution of cargo to the ﬁnal node stations. The process of cargo transportation is followed by the set rule of control. For such a model, one must determine possible modes of cargo transportation and describe their properties. This model is described by a ﬁnite-dimensional system of diﬀerential equations with nonlocal linear restrictions. The class of the solution satisfying nonlocal linear restrictions is extremely narrow. It results in the need for the “correct” extension of solutions of a system of diﬀerential equations to a class of quasi-solutions having the distinctive feature of gaps in a countable number of points. It was possible numerically using the Runge–Kutta method of the fourth order to build these quasi-solutions and determine their rate of growth. Let us note that in the technical plan the main complexity consisted in obtaining quasi-solutions satisfying the nonlocal linear restrictions. Furthermore, we investigated the dependence of quasi-solutions and, in particular, sizes of gaps (jumps) of solutions on a number of parameters of the model characterizing a rule of control, technologies for transportation of cargo and intensity of giving of cargo on a node station.

Let k be a field of characteristic zero, let G be a connected reductive algebraic group over k and let g be its Lie algebra. Let k(G), respectively, k(g), be the field of k- rational functions on G, respectively, g. The conjugation action of G on itself induces the adjoint action of G on g. We investigate the question whether or not the field extensions k(G)/k(G)^G and k(g)/k(g)^G are purely transcendental. We show that the answer is the same for k(G)/k(G)^G and k(g)/k(g)^G, and reduce the problem to the case where G is simple. For simple groups we show that the answer is positive if G is split of type A_n or C_n, and negative for groups of other types, except possibly G_2. A key ingredient in the proof of the negative result is a recent formula for the unramified Brauer group of a homogeneous space with connected stabilizers. As a byproduct of our investigation we give an affirmative answer to a question of Grothendieck about the existence of a rational section of the categorical quotient morphism for the conjugating action of G on itself.

Let G be a connected semisimple algebraic group over an algebraically closed field k. In 1965 Steinberg proved that if G is simply connected, then in G there exists a closed irreducible cross-section of the set of closures of regular conjugacy classes. We prove that in arbitrary G such a cross-section exists if and only if the universal covering isogeny Ĝ → G is bijective; this answers Grothendieck's question cited in the epigraph. In particular, for char k = 0, the converse to Steinberg's theorem holds. The existence of a cross-section in G implies, at least for char k = 0, that the algebra k[G]G of class functions on G is generated by rk G elements. We describe, for arbitrary G, a minimal generating set of k[G]G and that of the representation ring of G and answer two Grothendieck's questions on constructing generating sets of k[G]G. We prove the existence of a rational (i.e., local) section of the quotient morphism for arbitrary G and the existence of a rational cross-section in G (for char k = 0, this has been proved earlier); this answers the other question cited in the epigraph. We also prove that the existence of a rational section is equivalent to the existence of a rational W-equivariant map T- - - >G/T where T is a maximal torus of G and W the Weyl group.