Tag: Propagation

Sound Waves Propagation, Frequencies and Effects


Free Download Vitale Abagnali, "Sound Waves: Propagation, Frequencies and Effects "
English | ISBN: 161470001X | 2012 | 239 pages | PDF | 20 MB
In this book, the authors present current research in the study of the propagation, frequency and effects of sound waves. Topics discussed include time resolved visualisation and analysis on a single short acoustic wave generation; elastic vibrations of an isotropic plate with laser-induced atomic defects; sound velocity into turbulent medium; infrasound generation by turbulent convection; neutrons diffraction in a crystal under the influence of a sound wave and the transformation of sound waves in non-stationary media.

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The Dynamics of Front Propagation in Nonlocal Reaction-Diffusion Equations


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English | 2024 | ISBN: 3031777719 | 210 Pages | PDF EPUB (True) | 18 MB
The book provides a self-contained and complete description of the long time evolution of the solutions to a class of one-dimensional reaction-diffusion equations, in which the diffusion is given by an integral operator. The underlying motivation is the mathematical analysis of models for biological invasions. The model under study, while simple looking, is of current use in real-life situations. Interestingly, it arises in totally different contexts, such as the study of branching random walks in probability theory. While the model has attracted a lot of attention, and while many partial results about the time-asymptotic behaviour of its solutions have been proved over the last decades, some basic questions on the sharp asymptotics have remained unanswered. One ambition of this monograph is to close these gaps. In some of the situations that we envisage, the level sets organise themselves into an invasion front that is asymptotically linear in time, up to a correction that converges exponentially in time to a constant. In other situations that constitute the main and newest part of the work, the correction is asymptotically logarithmic in time. Despite these apparently different behaviours, there is an underlying common way of thinking that is underlined. At the end of each chapter, a long set of problems is proposed, many of them rather elaborate and suitable for master’s projects or even the first question in a PhD thesis. Open questions are also discussed. The ideas presented in the book apply to more elaborate systems modelling biological invasions or the spatial propagation of epidemics. The models themselves may be multidimensional, but they all have in common a mechanism imposing the propagation in a given direction; examples are presented in the problems that conclude each chapter. These ideas should also be useful in the treatment of further models that we are not able to envisage for the time being. The book is suitable for graduate or PhD students as well as researchers.

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Antennas and Propagation for Wireless Communication Systems (3rd Edition)


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English | 2025 | ISBN: 1394223048 | 752 Pages | PDF, EPUB (True) | 125 MB
The newly revised and thoroughly updated Third Edition of this classic and popular text, Antennas and Propagation for Wireless Communication Systems addresses fundamentals and practical applications of antennas and radio propagation commonly used in modern wireless communication systems, from the basic electromagnetic principles to the characteristics of the technology employed in the most recent systems deployed, with an outlook of forthcoming developments in the field.

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Antennas and Propagation for Wireless Communication Systems (3rd Edition)


Free Download Antennas and Propagation for Wireless Communication Systems
English | 2025 | ISBN: 1394223048 | 752 Pages | PDF, EPUB (True) | 125 MB
The newly revised and thoroughly updated Third Edition of this classic and popular text, Antennas and Propagation for Wireless Communication Systems addresses fundamentals and practical applications of antennas and radio propagation commonly used in modern wireless communication systems, from the basic electromagnetic principles to the characteristics of the technology employed in the most recent systems deployed, with an outlook of forthcoming developments in the field.

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Mathematical Problems in Wave Propagation Theory


Free Download Mathematical Problems in Wave Propagation Theory by V. M. Babich
English | PDF | 1970 | 109 Pages | ISBN : 1475703368 | 9.1 MB
The papers comprising this collection are directly or indirectly related to an important branch of mathematical physics – the mathematical theory of wave propagation and diffraction. The paper by V. M. Babich is concerned with the application of the parabolic-equation method (of Academician V. A. Fok and M. A, Leontovich) to the problem of the asymptotic behavior of eigenfunc tions concentrated in a neighborhood of a closed geodesie in a Riemannian space. The techniques used in this paper have been föund useful in solving certain problems in the theory of open resonators. The topic of G. P. Astrakhantsev’s paper is similar to that of the paper by V. M. Babich. Here also the parabolic-equation method is used to find the asymptotic solution of the elasticity equations which describes Love waves concentrated in a neighborhood of some surface ray. The paper of T. F. Pankratova is concerned with finding the asymptotic behavior of th~ eigenfunc tions of the Laplace operator from the exact solution for the surface of a triaxial ellipsoid and the re gion exterior to it. The first three papers of B. G. Nikolaev are somewhat apart from the central theme of the col lection; they treat the integral transforms with respect to associated Legendre functions of first kind and their applications. Examples of such applications are the use of this transform for the solution of integral equations with symmetrie kernels and for the solution of certain problems in the theory of electrical prospecting.

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