Download or read book Parabolic Wave Equations with Applications written by Michael D. Collins and published by Springer Nature. This book was released on 2019-11-04 with total page 135 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book introduces parabolic wave equations, their key methods of numerical solution, and applications in seismology and ocean acoustics. The parabolic equation method provides an appealing combination of accuracy and efficiency for many nonseparable wave propagation problems in geophysics. While the parabolic equation method was pioneered in the 1940s by Leontovich and Fock who applied it to radio wave propagation in the atmosphere, it thrived in the 1970s due to its usefulness in seismology and ocean acoustics. The book covers progress made following the parabolic equation’s ascendancy in geophysics. It begins with the necessary preliminaries on the elliptic wave equation and its analysis from which the parabolic wave equation is derived and introduced. Subsequently, the authors demonstrate the use of rational approximation techniques, the Padé solution in particular, to find numerical solutions to the energy-conserving parabolic equation, three-dimensional parabolic equations, and horizontal wave equations. The rest of the book demonstrates applications to seismology, ocean acoustics, and beyond, with coverage of elastic waves, sloping interfaces and boundaries, acousto-gravity waves, and waves in poro-elastic media. Overall, it will be of use to students and researchers in wave propagation, ocean acoustics, geophysical sciences and more.

Download or read book Parabolic Equation Methods for Electromagnetic Wave Propagation written by Mireille Levy and published by IET. This book was released on 2000 with total page 360 pages. Available in PDF, EPUB and Kindle. Book excerpt: Provides scientists and engineers with a tool for accurate assessment of diffraction and ducting on radio and radar systems. The author gives the mathematical background to parabolic equations modeling and describes simple parabolic equation algorithms before progressing to more advanced topics such as domain truncation, the treatment of impedance boundaries, and the implementation of very fast hybrid methods combining ray-tracing and parabolic equation techniques. The last three chapters are devoted to scattering problems, with application to propagation in urban environments and to radar-cross- section computation. Annotation copyrighted by Book News, Inc., Portland, OR

Download or read book Parabolic Equations with Irregular Data and Related Issues written by Claude Le Bris and published by Walter de Gruyter GmbH & Co KG. This book was released on 2019-06-17 with total page 264 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book studies the existence and uniqueness of solutions to parabolic-type equations with irregular coefficients and/or initial conditions. It elaborates on the DiPerna-Lions theory of renormalized solutions to linear transport equations and related equations, and also examines the connection between the results on the partial differential equation and the well-posedness of the underlying stochastic/ordinary differential equation.

Download or read book Radio Wave Propagation and Parabolic Equation Modeling written by Gokhan Apaydin and published by John Wiley & Sons. This book was released on 2017-08-31 with total page 161 pages. Available in PDF, EPUB and Kindle. Book excerpt: An important contribution to the literature that introduces powerful new methods for modeling and simulating radio wave propagation A thorough understanding of electromagnetic wave propagation is fundamental to the development of sophisticated communication and detection technologies. The powerful numerical methods described in this book represent a major step forward in our ability to accurately model electromagnetic wave propagation in order to establish and maintain reliable communication links, to detect targets in radar systems, and to maintain robust mobile phone and broadcasting networks. The first new book on guided wave propagation modeling and simulation to appear in nearly two decades, Radio Wave Propagation and Parabolic Equation Modeling addresses the fundamentals of electromagnetic wave propagation generally, with a specific focus on radio wave propagation through various media. The authors explore an array of new applications, and detail various virtual electromagnetic tools for solving several frequent electromagnetic propagation problems. All of the methods described are presented within the context of real-world scenarios typifying the differing effects of various environments on radio-wave propagation. This valuable text: Addresses groundwave and surface wave propagation Explains radar applications in terms of parabolic equation modeling and simulation approaches Introduces several simple and sophisticated MATLAB scripts Teaches applications that work with a wide range of electromagnetic, acoustic and optical wave propagation modeling Presents the material in a quick-reference format ideal for busy researchers and engineers Radio Wave Propagation and Parabolic Equation Modeling is a critical resource forelectrical, electronics, communication, and computer engineers working on industrial and military applications that rely on the directed propagation of radio waves. It is also a useful reference for advanced engineering students and academic researchers.

Download or read book The Extended Parabolic Equation Method and Implication of Results for Atmospheric Millimeter Wave and Optical Propagation written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-11 with total page 38 pages. Available in PDF, EPUB and Kindle. Book excerpt: The extended wide-angle parabolic wave equation applied to electromagnetic wave propagation in random media is considered. A general operator equation is derived which gives the statistical moments of an electric field of a propagating wave. This expression is used to obtain the first and second order moments of the wave field and solutions are found that transcend those which incorporate the full paraxial approximation at the outset. Although these equations can be applied to any propagation scenario that satisfies the conditions of application of the extended parabolic wave equation, the example of propagation through atmospheric turbulence is used. It is shown that in the case of atmospheric wave propagation and under the Markov approximation (i.e., the -correlation of the fluctuations in the direction of propagation), the usual parabolic equation in the paraxial approximation is accurate even at millimeter wavelengths. The methodology developed here can be applied to any qualifying situation involving random propagation through turbid or plasma environments that can be represented by a spectral density of permittivity fluctuations.Manning, Robert M.Glenn Research CenterELECTROMAGNETIC WAVE TRANSMISSION; WAVE PROPAGATION; ATMOSPHERIC TURBULENCE; MILLIMETER WAVES; OPTICAL COMMUNICATION; DISTRIBUTION MOMENTS; ELECTRIC FIELDS; PERMITTIVITY; PLASMAS (PHYSICS); SPECTRA

Download or read book The Extended Parabolic Equation Method and Implication of Results for Atmospheric Millimeter Wave and Optical Propagation written by Robert M. Manning and published by BiblioGov. This book was released on 2013-07 with total page 40 pages. Available in PDF, EPUB and Kindle. Book excerpt: The extended wide-angle parabolic wave equation applied to electromagnetic wave propagation in random media is considered. A general operator equation is derived which gives the statistical moments of an electric field of a propagating wave. This expression is used to obtain the first and second order moments of the wave field and solutions are found that transcend those which incorporate the full paraxial approximation at the outset. Although these equations can be applied to any propagation scenario that satisfies the conditions of application of the extended parabolic wave equation, the example of propagation through atmospheric turbulence is used. It is shown that in the case of atmospheric wave propagation and under the Markov approximation (i.e., the -correlation of the fluctuations in the direction of propagation), the usual parabolic equation in the paraxial approximation is accurate even at millimeter wavelengths. The methodology developed here can be applied to any qualifying situation involving random propagation through turbid or plasma environments that can be represented by a spectral density of permittivity fluctuations.

Download or read book Well posedness of One way Wave Equations and Absorbing Boundary Conditions written by Lloyd Nicholas Trefethen and published by . This book was released on 1985 with total page 32 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Traveling Wave Solutions of Parabolic Systems written by A. I. Volpert and published by American Mathematical Soc.. This book was released on with total page 474 pages. Available in PDF, EPUB and Kindle. Book excerpt: The theory of travelling waves described by parabolic equations and systems is a rapidly developing branch of modern mathematics. This book presents a general picture of current results about wave solutions of parabolic systems, their existence, stability, and bifurcations. With introductory material accessible to non-mathematicians and a nearly complete bibliography of about 500 references, this book is an excellent resource on the subject.

Download or read book Geometric Sturmian Theory of Nonlinear Parabolic Equations and Applications written by Victor A. Galaktionov and published by CRC Press. This book was released on 2004-05-24 with total page 384 pages. Available in PDF, EPUB and Kindle. Book excerpt: Unlike the classical Sturm theorems on the zeros of solutions of second-order ODEs, Sturm's evolution zero set analysis for parabolic PDEs did not attract much attention in the 19th century, and, in fact, it was lost or forgotten for almost a century. Briefly revived by Plya in the 1930's and rediscovered in part several times since, it was not un

Download or read book Fractional in Time Semilinear Parabolic Equations and Applications written by Ciprian G. Gal and published by Springer. This book was released on 2020-11-04 with total page 184 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book provides a unified analysis and scheme for the existence and uniqueness of strong and mild solutions to certain fractional kinetic equations. This class of equations is characterized by the presence of a nonlinear time-dependent source, generally of arbitrary growth in the unknown function, a time derivative in the sense of Caputo and the presence of a large class of diffusion operators. The global regularity problem is then treated separately and the analysis is extended to some systems of fractional kinetic equations, including prey-predator models of Volterra–Lotka type and chemical reactions models, all of them possibly containing some fractional kinetics. Besides classical examples involving the Laplace operator, subject to standard (namely, Dirichlet, Neumann, Robin, dynamic/Wentzell and Steklov) boundary conditions, the framework also includes non-standard diffusion operators of "fractional" type, subject to appropriate boundary conditions. This book is aimed at graduate students and researchers in mathematics, physics, mathematical engineering and mathematical biology, whose research involves partial differential equations.

Download or read book Nonlocal and Abstract Parabolic Equations and Their Applications written by Piotr Mucha and published by . This book was released on 2009 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling Electromagnetic Wave Propagation Over the Ocean Using the Parabolic Wave Equation written by Cary L. Biros and published by . This book was released on 1999 with total page 114 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Parabolic Wave Equation for Surface Water Waves written by Philip L. F. Liu and published by . This book was released on 1986 with total page 84 pages. Available in PDF, EPUB and Kindle. Book excerpt: In this report, the mild-slope equation describing the combined refraction and diffraction of small amplitude water waves is re-derived and reviewed. The relationship between the mild-slope equation and the ray theory is presented. The physical justifications for the parabolic approximation are then discussed. Parabolic wave equations in various forms are derived to investigate the effects of energy dissipation, reflection, and nonlinearity. Keywords: Mathematical models; Hydrodynamics; Water wave propagation; Water wave diffraction; Water wave refraction.

Download or read book Traveling wave solutions of parabolic systems written by Aĭzik Isaakovich Volʹpert and published by American Mathematical Society(RI). This book was released on 1994 with total page 448 pages. Available in PDF, EPUB and Kindle. Book excerpt: The theory of traveling waves described by parabolic equations and systems is a rapidly developing branch of modern mathematics. This book presents a general picture of current results about wave solutions of parabolic systems, their existence, stability, and bifurcations. The main part of the book contains original approaches developed by the authors. Among these are a description of the long-term behavior of the solutions by systems of waves; construction of rotations of vector fields for noncompact operators describing wave solutions; a proof of the existence of waves by the Leray-Schauder method; local, global, and nonlinear stability analyses for some classes of systems; and a determination of the wave velocity by the minimax method and the method of successive approximations. The authors show that wide classes of reaction-diffusion systems can be reduced to so-called monotone and locally monotone systems. This fundamental result allows them to apply the theory to combustion and chemical kinetics. With introductory material accessible to nonmathematicians and a nearly complete bibliography of about 500 references, this book is an excellent resource on the subject.

Download or read book Parabolic Approximations of the Reduced Wave Equations written by Vijay G. Panchang and published by . This book was released on 1989 with total page 141 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Handbook of Differential Equations Evolutionary Equations written by C.M. Dafermos and published by Elsevier. This book was released on 2011-09-22 with total page 653 pages. Available in PDF, EPUB and Kindle. Book excerpt: The material collected in this volume reflects the active present of this area of mathematics, ranging from the abstract theory of gradient flows to stochastic representations of non-linear parabolic PDE's. Articles will highlight the present as well as expected future directions of development of the field with particular emphasis on applications. The article by Ambrosio and Savaré discusses the most recent development in the theory of gradient flow of probability measures. After an introduction reviewing the properties of the Wasserstein space and corresponding subdifferential calculus, applications are given to evolutionary partial differential equations. The contribution of Herrero provides a description of some mathematical approaches developed to account for quantitative as well as qualitative aspects of chemotaxis. Particular attention is paid to the limits of cell's capability to measure external cues on the one hand, and to provide an overall description of aggregation models for the slim mold Dictyostelium discoideum on the other. The chapter written by Masmoudi deals with a rather different topic - examples of singular limits in hydrodynamics. This is nowadays a well-studied issue given the amount of new results based on the development of the existence theory for rather general systems of equations in hydrodynamics. The paper by DeLellis addreses the most recent results for the transport equations with regard to possible applications in the theory of hyperbolic systems of conservation laws. Emphasis is put on the development of the theory in the case when the governing field is only a BV function. The chapter by Rein represents a comprehensive survey of results on the Poisson-Vlasov system in astrophysics. The question of global stability of steady states is addressed in detail. The contribution of Soner is devoted to different representations of non-linear parabolic equations in terms of Markov processes. After a brief introduction on the linear theory, a class of non-linear equations is investigated, with applications to stochastic control and differential games. The chapter written by Zuazua presents some of the recent progresses done on the problem of controllabilty of partial differential equations. The applications include the linear wave and heat equations,parabolic equations with coefficients of low regularity, and some fluid-structure interaction models. - Volume 1 focuses on the abstract theory of evolution - Volume 2 considers more concrete probelms relating to specific applications - Volume 3 reflects the active present of this area of mathematics, ranging from the abstract theory of gradient flows to stochastic representations of non-linear PDEs

Download or read book Ocean Acoustic Propagation by Finite Difference Methods written by D. Lee and published by Elsevier. This book was released on 2014-06-28 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: A concise guide to the theory and application of numerical methods for predicting ocean acoustic propagation, also providing an introduction to numerical methods, with an overview of those methods presently in use. An in-depth development of the implicit-finite-difference technique is presented together with bench-mark test examples included to demonstrate its application to realistic ocean environments. Other applications include atmospheric acoustics, plasma physics, quantum mechanics, optics and seismology.