Inverse problems in wave propagation occur in geophysics, ocean acoustics, civil and environmental engineering, ultrasonic non-destructive testing, biomedical ultrasonics, radar, astrophysics, as well as other areas of science and technology. The papers in this volume cover these scientific and technical topics, together with fundamental mathematical investigations of the relation between waves and scatterers.

This monograph develops the theory of noise mechanisms and measurements, and describes general noise characteristics and computational methods. The vast ambient noise literature is concisely summarized using theory combined with key representative results.

The air sea boundary interaction zone is described in terms of nondimensional variables requisite for future experiments. Noise field coherency, rare directional measurements, and unique basin scale computations and methods are presented. The use of satellite measurements in these basin scale models is demonstrated. A series of appendices provides in-depth mathematical treatments which will be of interest to graduate students and active researchers.

Guest Editor: JOSEF A. NOSSEK This is a special issue of the Journal of VLSI Signal Processing comprising eight contributions invited for publica tion on the basis of novel work presented in a special session on "Parallel Processing on VLSI Arrays" at the International Symposium on Circuits and Systems (ISCAS) held in New Orleans in May 1990. Massive parallelism to cope with high-speed requirements stemming from real-time applications and the restrictions in architectural and circuit design, such as regularity and local connectedness, brought about by the VLSI technology are the key questions addressed in these eight papers. They can be grouped into three subsections elaborating on: * Simulation of continuous physical systems, i. e. , numerically solving partial differential equations. * Neural architectures for image processing and pattern recognition. * Systolic architectures for implementing regular and irregular algorithms in VLSI technology. The paper by A. Fettweis and O. Nitsche advocates a signal processing approach for the numerical integration of partial differential equations (PD Es). It is based on the principles of multidimensional wave digital filters (MDWDFs) thereby preserving the passivity of energy dissipating physical systems. It is particularly suited for systems ofPDEs involving time and finite propagation speed. The basic ideas are explained using Maxwell's equa tions as a vehicle for the derivation of a multidimensional equivalent circuit representing the spatially infinitely extended arrangement with only very few circuit elements.

What is this sound? What does that sound indicate? These are two questions frequently heard in daily conversation. Sound results from the vibrations of elastic media and in daily life provides informative signals of events happening in the surrounding environment. In interpreting auditory sensations, the human ear seems particularly good at extracting the signal signatures from sound waves. Although exploring auditory processing schemes may be beyond our capabilities, source signature analysis is a very attractive area in which signal-processing schemes can be developed using mathematical expressions. This book is inspired by such processing schemes and is oriented to signature analysis of waveforms. Most of the examples in the book are taken from data of sound and vibrations; however, the methods and theories are mostly formulated using mathematical expressions rather than by acoustical interpretation. This book might therefore be attractive and informative for scientists, engineers, researchers, and graduate students who are interested in the mathematical representation of signals and the applications of Fourier analysis. The book can be described as being practically self-contained but does assume readers are familiar with introductory topics in discrete signal processing, as in the discrete Fourier transform. Hence this book might be also usable as a textbook in graduate courses in applied mathematics on topics such as complex functions. Almost all scientific phenomena are sensed as waves propagating in some space. Over the years, waveform analysis has therefore been one of the resilient academic areas of study and still is seen as fertile ground for development. In particular, waveform analysis based on the theory of linear systems would be a good example where a physical interpretation can be given to the mathematical theory of complex functions in terms of magnitude, angle, poles, and zeros of complex functions. For readers who are interested in the physical aspects of sound and vibration data or elementary formulation of wave equations and their solutions, the book Sound and Signals by M. Tohyama (Springer 2011) is recommended. It can serve as a complementary companion to this present volume or independently as a good reference.

This volume gives a comprehensive coverage of Internet technologies. It provides both a contemporary and extensive review of developments in the field and also gives details of research. Areas covered include: developments in the network protocols on which the Internet is based; the evolving capability of the Internet to carry audio and video traffic; and the development in security and payment technologies which are opening up a wide range of commercial electronic applications. As the importance of the Internet continues to increase, this book should be of interest to businesses. Several case studies of on-line services are included. The text should prove useful not only to researchers in the communications and computing sectors working directly in the development of the technology, but also to people working in banking and finance. Business users of the Internet should also find the book to be useful in the development of such applications as Internet trading and corporate intranets.

This corrected version of the landmark 1981 textbook introduces the physical principles and theoretical basis of acoustics with deep mathematical rigor, concentrating on concepts and points of view that have proven useful in applications such as noise control, underwater sound, architectural acoustics, audio engineering, nondestructive testing, remote sensing, and medical ultrasonics. Since its publication, this text has been used as part of numerous acoustics-related courses across the world, and continues to be used widely today. During its writing, the book was fine-tuned according to insights gleaned from a broad range of classroom settings. Its careful design supports students in their pursuit of a firm foundation while allowing flexibility in course structure. The book can easily be used in single-term or full-year graduate courses and includes problems and answers. This rigorous and essential text is a must-have for any practicing or aspiring acoustician.

This volume is based on the fifth international conference of quantum bio-informatics held at the QBI Center of Tokyo University of Science.This volume provides a platform to connect mathematics, physics, information and life sciences, and in particular, research for new paradigm for information science and life science on the basis of quantum theory.The following topics are discussed:

A consequence of the description of the superfluid condensate in superfluid He or in superconductors as a single macroscopic quantum state is the quantization of circulation, resulting in quantized vortex lines. This book draws no distinction between superfluid He3 and He4 and superconductors. It examines theoretical and experimental progress in understanding of the vortex state in both superconductors and superfluids, from lectures given by both experimentalists and theoreticians, who gathered in Cargese for a NATO ASI. The peculiar features related to short coherence lengths, 2D geometry, high temperatures, disorder and pinning are discussed.

This book presents an analytical theory of the electronic states in ideal low dimensional systems and finite crystals based on a differential equation theory approach. It provides precise and fundamental understandings on the electronic states in ideal low-dimensional systems and finite crystals, and offers new insights into some of the basic problems in low-dimensional systems, such as the surface states and quantum confinement effects, etc., some of which are quite different from what is traditionally believed in the solid state physics community. Many previous predictions have been confirmed in subsequent investigations by other authors on various relevant problems. In this new edition, the theory is further extended to one-dimensional photonic crystals and phononic crystals, and a general theoretical formalism for investigating the existence and properties of surface states/modes in semi-infinite one-dimensional crystals is developed. In addition, there are various revisions and improvements, including using the Kronig-Penney model to illustrate the analytical theory and make it easier to understand. This book is a valuable resource for solid-state physicists and material scientists.

This book uses asymptotic methods to obtain simple approximate analytic solutions to various problems within mechanics, notably wave processes in heterogeneous materials. Presenting original solutions to common issues within mechanics, this book builds upon years of research to demonstrate the benefits of implementing asymptotic techniques within mechanical engineering and material science. Focusing on linear and nonlinear wave phenomena in complex micro-structured solids, the book determines their global characteristics through analysis of their internal structure, using homogenization and asymptotic procedures, in line with the latest thinking within the field. The book's cutting-edge methodology can be applied to optimal design, non-destructive control and in deep seismic sounding, providing a valuable alternative to widely used numerical methods. Using case studies, the book covers topics such as elastic waves in nonhomogeneous materials, regular and chaotic dynamics based on continualisation and discretization and vibration localization in 1D Linear and Nonlinear lattices. The book will be of interest to students, research engineers, and professionals specialising in mathematics and physics as well as mechanical and civil engineering.

This introductory text emphasises physical principles, rather than the mathematics. Each topic begins with a discussion of the physical characteristics of the motion or system. The mathematics is kept as clear as possible, and includes elegant mathematical descriptions where possible. Designed to provide a logical development of the subject, the book is divided into two sections, vibrations followed by waves. A particular feature is the inclusion of many examples, frequently drawn from everyday life, along with more cutting-edge ones. Each chapter includes problems ranging in difficulty from simple to challenging and includes hints for solving problems. Numerous worked examples included throughout the book.

This book focuses on dynamic antiplane problems of piezoelectric ceramics. It presents relatively simple theoretical solutions to many such problems, and attempts to use these solutions to demonstrate the operation and design of several acoustic wave devices. Some of the solutions are able to show the underlying physics clearly without the need for numerical computation. The problems treated include the propagation of plate waves, surface waves, interface waves, Love waves, gap waves, and vibrations of finite bodies of various shapes with applications in resonators, mass sensors, fluid sensors, interface sensors, phononic crystals, piezoelectric generators or power harvesters, piezoelectric transformers, power or signal transmission through an elastic wall, and acoustic wave excitation and detection for nondestructive evaluation.

A systematic study of chaotic ray dynamics in underwater acoustic waveguides began in the mid-1990s when it was realized that this factor plays a crucial role in long-range sound propagation in the ocean. The phenomenon of ray chaos and its manifestation at a finite wavelength - wave chaos - have been investigated by combining methods from the theory of wave propagation and the theory of dynamical and quantum chaos.This book is the first monograph summarizing results obtained in this field. Emphasis is made on the exploration of ray and modal structures of the wave field in an idealized environmental model with periodic range dependence and in a more realistic model with sound speed fluctuations induced by random internal waves. The book is intended for acousticians investigating the long-range sound transmission through the fluctuating ocean and also for researchers studying waveguide propagation in other media. It will be of major interest to scientists working in the field of dynamical and quantum chaos.

This book will serve as a reference guide, and state-of-the-art review, for the wide spectrum of numerical models and computational techniques available to solve some of the most challenging problems in coastal engineering. The topics covered in this book, are explained fundamentally from a numerical perspective and also include practical examples applications. Important classic themes such as wave generation, propagation and breaking, turbulence modelling and sediment transport are complemented by hot topics such as fluid and structure interaction or multi-body interaction to provide an integral overview on numerical techniques for coastal engineering. Through the vision of 10 high impact authors, each an expert in one or more of the fields included in this work, the chapters offer a broad perspective providing several different approaches, which the readers can compare critically to select the most suitable for their needs. Advanced Numerical Modelling of Wave Structure Interaction will be useful for a wide audience, including PhD students, research scientists, numerical model developers and coastal engineering consultants alike.

Surface Acoustic Waves in Inhomogeneous Media covers almost all important problems of the interaction of different types of surface acoustic waves with surface inhomogeneities. The problems of surface acoustic wave interaction with periodic topographic gratings widely used in filters and resonators are under careful consideration. The most important results of surface wave scattering by local defects such as grooves, random roughness, elastic wedges are given. Different theoretical approaches and practical rules for solving the surface wave problems are presented.

A study in the development of flow adaptive numerical schemes in computational hydraulics directed to enhancing modelling capabilities. Examples covered include additional flow resistance due to flexible vegetation; one-dimensional supercritical flow; and flow in networks of channels.

Modeling of Extreme Waves in Technology and Nature is a two-volume set, comprising Evolution of Extreme Waves and Resonances (Volume I) and Extreme Waves and Shock-Excited Processes in Structures and Space Objects (Volume II). The theory of waves is generalized on cases of extreme waves. The formation and propagation of extreme waves of various physical and mechanical nature (surface, elastoplastic, fracture, thermal, evaporation) in liquid and solid media, and in structural elements contacting with bubbly and cryogenic liquids are considered analytically and numerically. The occurrence of tsunamis, giant ocean waves, turbulence, and different particle-waves is described as resonant natural phenomena. Nonstationary and periodic waves are considered using models of continuum. The change in the state of matter is taken into account using wide-range determining equations. The desire for the simplest and at the same time general description of extreme wave phenomena that takes the reader to the latest achievements of science is the main thing that characterizes this book and is revolutionary for wave theory. A description of a huge number of observations, experimental data, and calculations is also given.

Aviation noise remains the primary hindrance to expansion of airport and airspace capacity in the United States. This book describes the development and practice of U.S. aircraft noise regulation, as well as the practical consequences of regulatory policy. Starting in the pre-jet transport era, the book traces the development of the modern framework for characterizing, standardizing, predicting, disclosing, and mitigating aircraft noise and its effects on airport-vicinity communities. Among other matters, the book treats noise-related consequences of the 1978 deregulation of the airline industry; prediction and mitigation of community reaction to airport noise; land use compatibility planning; recent research and industry trends; and some suggestions for potential improvements to current policy. Initial chapters describe the assumptions underlying aircraft noise regulation, and lay out the chronology of U.S. aircraft noise regulatory practice. Later chapters provide overviews of population-level effects of aviation noise, including health effects, speech and sleep interference, and annoyance. Readers will learn why predictions of the prevalence of aircraft noise-induced annoyance have systematically underestimated adverse community response to aircraft noise, and how such underestimation has complicated approval and funding of airport and airspace improvement projects. They will also learn why attempts at noise-compatible land use planning are seldom fully successful.

This volume collects the papers from the World Conference on Acoustic Emission 2017 (WCAE-2017) in Xi'an, China. The latest research and applications of acoustic emission (AE) are explored, with a particular emphasis on detecting and processing AE signals, the development of AE instrument and testing standards, AE of materials, engineering structures and systems, including the processing of collected data and analytical techniques. Numerous case studies are also included. This proceedings volume will appeal to students, professors and researchers working in these fields as physicists and/or engineers.

What is a musical instrument? What are the musical instruments of the future? This anthology presents thirty papers selected from the fifteen year long history of the International Conference on New Interfaces for Musical Expression (NIME). NIME is a leading music technology conference, and an important venue for researchers and artists to present and discuss their explorations of musical instruments and technologies. Each of the papers is followed by commentaries written by the original authors and by leading experts. The volume covers important developments in the field, including the earliest reports of instruments like the reacTable, Overtone Violin, Pebblebox, and Plank. There are also numerous papers presenting new development platforms and technologies, as well as critical reflections, theoretical analyses and artistic experiences. The anthology is intended for newcomers who want to get an overview of recent advances in music technology. The historical traces, meta-discussions and reflections will also be of interest for longtime NIME participants. The book thus serves both as a survey of influential past work and as a starting point for new and exciting future developments.

This definitive textbook provides students with a comprehensive introduction to acoustics. Beginning with the basic physical ideas, Acoustics balances the fundamentals with engineering aspects, applications and electroacoustics, also covering music, speech and the properties of human hearing. The concepts of acoustics are exposed and applied in:

• room acoustics
• sound insulation in buildings
• noise control
• underwater sound and ultrasound.

Scientifically thorough, but with mathematics kept to a minimum, Acoustics is the perfect introduction to acoustics for students at any level of mechanical, electrical or civil engineering courses and an accessible resource for architects, musicians or sound engineers requiring a technical understanding of acoustics and their applications.

This definitive textbook provides students with a comprehensive introduction to acoustics. Beginning with the basic physical ideas, Acoustics balances the fundamentals with engineering aspects, applications and electroacoustics, also covering music, speech and the properties of human hearing. The concepts of acoustics are exposed and applied in:

• room acoustics
• sound insulation in buildings
• noise control
• underwater sound and ultrasound.

Scientifically thorough, but with mathematics kept to a minimum, Acoustics is the perfect introduction to acoustics for students at any level of mechanical, electrical or civil engineering courses and an accessible resource for architects, musicians or sound engineers requiring a technical understanding of acoustics and their applications.

This book addresses the modelling of mechanical waves by asking the right questions about them and trying to find suitable answers. The questions follow the analytical sequence from elementary understandings to complicated cases, following a step-by-step path towards increased knowledge. The focus is on waves in elastic solids, although some examples also concern non-conservative cases for the sake of completeness. Special attention is paid to the understanding of the influence of microstructure, nonlinearity and internal variables in continua. With the help of many mathematical models for describing waves, physical phenomena concerning wave dispersion, nonlinear effects, emergence of solitary waves, scales and hierarchies of waves as well as the governing physical parameters are analysed. Also, the energy balance in waves and non-conservative models with energy influx are discussed. Finally, all answers are interwoven into the canvas of complexity.

This volume gathers the latest advances and innovations in the field of flow-induced vibration and noise, as presented by leading international researchers at the 3rd International Symposium on Flow Induced Noise and Vibration Issues and Aspects (FLINOVIA), which was held in Lyon, France, in September 2019. It explores topics such as turbulent boundary layer-induced vibration and noise, tonal noise, noise due to ingested turbulence, fluid-structure interaction problems, and noise control techniques. The authors' backgrounds represent a mix of academia, government, and industry, and several papers include applications to important problems for underwater vehicles, aerospace structures and commercial transportation. The book offers a valuable reference guide for all those interested in measurement, modelling, simulation and reproduction of the flow excitation and flow induced structural response.

The book presents a broad-scope analysis of piezoelectric electromechanical transducers and the related aspects of practical transducer design for underwater applications. It uses an energy method for analyzing transducer problems that provides the physical insight important for the understanding of electromechanical devices. Application of the method is first illustrated with transducer examples that can be modeled as systems with a single degree of freedom, (such as spheres, short cylinders, bars and flexural disks and plates made of piezoelectric ceramics). Thereupon, transducers are modeled as devices with multiple degrees of freedom. In all these cases, results of modeling are presented in the form of equivalent electromechanical circuits convenient for the calculation of the transducers' operational characteristics. Special focus is made on the effects of coupled vibrations in mechanical systems on transducer performance. The book also provides extensive coverage of acoustic radiation including acoustic interaction between the transducers. The book is inherently multidisciplinary. It provides essential background regarding the vibration of elastic passive and piezoelectric bodies, piezoelectricity, acoustic radiation, and transducer characterization. Scientists and engineers working in the field of electroacoustics and those involved in education in the field will find this material useful not only for underwater acoustics, but also for electromechanics, energy conversion and medical ultrasonics. Part II contains general information on vibration of mechanical systems, electromechanical conversion in the deformed piezoceramic bodies, and acoustic radiation that can be used independently for treatment transducers of different type.