QUASI-conservative Systems


Book Description

This monograph presents the theory of nonconservative systems close to nonlinear integrable ones. With the example of concrete quasi-conservative systems close to nonintegrable ones, the results of numerical analysis are given, and the problem of applying the small parameter method is analyzed.The fundamantal part of the book deals with the investigation of the perturbable systems. Both autonomous and nonautonomous (periodic in time) systems are considered. The global analysis of systems close to the two-dimensional Hamiltonian ones takes a central place in the text. This global analysis includes the solution to problems such as the limit cycles, resonances, and nonregular dynamics. For the autonomous systems, one should note the analysis of the standard (Duffing and pendulum) equations including the solution to the ?weakened? 16 Hilbert's problem, and for the nonautonomous systems one should note the mathematical foundations of the theory of synchronization of oscillations (the existence of new regimes, and the passage of invariant tori across the resonance zones under the change of detuning). The presentation is accompanied by examples.




Quasi-conservative Systems: Cycles, Resonances And Chaos


Book Description

This monograph presents the theory of nonconservative systems close to nonlinear integrable ones. With the example of concrete quasi-conservative systems close to nonintegrable ones, the results of numerical analysis are given, and the problem of applying the small parameter method is analyzed.The fundamantal part of the book deals with the investigation of the perturbable systems. Both autonomous and nonautonomous (periodic in time) systems are considered. The global analysis of systems close to the two-dimensional Hamiltonian ones takes a central place in the text. This global analysis includes the solution to problems such as the limit cycles, resonances, and nonregular dynamics. For the autonomous systems, one should note the analysis of the standard (Duffing and pendulum) equations including the solution to the “weakened” 16 Hilbert's problem, and for the nonautonomous systems one should note the mathematical foundations of the theory of synchronization of oscillations (the existence of new regimes, and the passage of invariant tori across the resonance zones under the change of detuning). The presentation is accompanied by examples.







Systems of Quasilinear Equations and Their Applications to Gas Dynamics


Book Description

This book is essentially a new edition, revised and augmented by results of the last decade, of the work of the same title published in 1968 by ``Nauka.'' It is devoted to mathematical questions of gas dynamics. Topics covered include Foundations of the Theory of Systems of Quasilinear Equations of Hyperbolic Type in Two Independent Variables; Classical and Generalized Solutions of One-Dimensional Gas Dynamics; Difference Methods for Solving the Equations of Gas Dynamics; and Generalized Solutions of Systems of Quasilinear Equations of Hyperbolic Type.




Numerical Solution of Quasi-Conservative Hyperbolic Systems - The Cylindrical Shock Problem


Book Description

The paper discusses the numerical solution of hyperbolic systems of partial differential equations which are in quasi-conservation form. A basic Lax-Wendroff like scheme is developed. In order to treat problems with discontinuous solutions an iterative procedure is proposed. The stability and convergence of the various schemes are investigated. It is shown that it is possible to have time steps considerably larger than those allowed according to the C.F.L. (Courant - Friedricks - Levy) criterion. The method is then applied to the case of converging-diverging cylindrical shock waves. Detailed behavior near the axis at the time of shock coalescence is obtained, as well as the general flow field at various times. The results are compared with Payne and the differences are pointed out. (Author).




Dynamics of Synchronising Systems


Book Description

This book presents a rational scheme of analysis for the periodic and quasi-periodic solution of a broad class of problems within technical and celestial mechanics. It develops steps for the determination of sufficiently general averaged equations of motion, which have a clear physical interpretation and are valid for a broad class of weak-interaction problems in mechanics. The criteria of stability regarding stationary solutions of these equations are derived explicitly and correspond to the extremum of a special "potential" function. Much consideration is given to applications in vibrational technology, electrical engineering and quantum mechanics, and a number of results are presented that are immediately useful in engineering practice. The book is intended for mechanical engineers, physicists, as well as applied mathematicians specializing in the field of ordinary differential equations.




Mechanical Systems, Classical Models


Book Description

All phenomena in nature are characterized by motion. Mechanics deals with the objective laws of mechanical motion of bodies, the simplest form of motion. In the study of a science of nature, mathematics plays an important rôle. Mechanics is the first science of nature which has been expressed in terms of mathematics, by considering various mathematical models, associated to phenomena of the surrounding nature. Thus, its development was influenced by the use of a strong mathematical tool. As it was already seen in the first two volumes of the present book, its guideline is precisely the mathematical model of mechanics. The classical models which we refer to are in fact models based on the Newtonian model of mechanics, that is on its five principles, i.e.: the inertia, the forces action, the action and reaction, the independence of the forces action and the initial conditions principle, respectively. Other models, e.g., the model of attraction forces between the particles of a discrete mechanical system, are part of the considered Newtonian model. Kepler’s laws brilliantly verify this model in case of velocities much smaller then the light velocity in vacuum.




Regular and Chaotic Oscillations


Book Description

This text maps out the modern theory of non-linear oscillations. The material is presented in a non-traditional manner and emphasises the new results of the theory - obtained partially by the author, who is one of the leading experts in the area. Among the topics are: synchronization and chaotization of self-oscillatory systems and the influence of weak random vibration on modification of characteristics and behaviour of the non-linear systems.