The Helmholtz Equation Least Squares Method


Book Description

This book represents the HELS (Helmholtz equation least squares) theory and its applications for visualizing acoustic radiation from an arbitrarily shaped vibrating structure in free or confined space. It culminates the most updated research work of the author and his graduate students since 1997. The book contains six chapters. The first serves as a review of the fundamentals in acoustics and the rest cover five specific topics on the HELS theory.




Holography


Book Description

Holography of today is a broad field developed in the meeting between optics and the digital world of computers. A hologram usually contains more or different information on the observed scene than a regular image of the same scene. The development of the field has been accelerated lately due to the improvement of digital cameras, computers, light sources, and spatial light modulators. As a multidisciplinary area, holography connects experts in electro-optical engineering, image processing, and computer algorithms. More experts are needed when holography is utilized in various applications such as microscopy, industrial inspection, biomedicine, and entertainment. This book provides an overview of the world of holography from the aspect of concepts, system architectures, and applications.




Sound Visualization and Manipulation


Book Description

Unique in addressing two different problems – sound visualization and manipulation – in a unified way Advances in signal processing technology are enabling ever more accurate visualization of existing sound fields and precisely defined sound field production. The idea of explaining both the problem of sound visualization and the problem of the manipulation of sound within one book supports this inter-related area of study. With rapid development of array technologies, it is possible to do much in terms of visualization and manipulation, among other technologies involved with the spatial distribution of sound. This book aims to explore various basic functions for the visualization and manipulation and demonstrate to the reader how these properties determine the quality of visualization and manipulation. The first half of the book introduces some basic and general concepts and theories and the second part of the book explains a number of techniques in sound visualization and manipulation. It offers a unified presentation to two very different topics - sound field visualization techniques based on microphone arrays, and techniques for generation of controlled sound fields using loudspeaker arrays. The authors emphasize the similarities between these two physical problems and between the mathematical methods used for solving them. With extensive examples throughout the book, chapters include: Acoustic Wave Equation and its Basic Physical Measures, Acoustic Wave Equation and its Basic Physical Measures, Basic Theory of Sound Visualization, Acoustic Holography, Beamforming, Basic Theory of Sound Manipulation, Sound Focusing, and Sound Field Reproduction. The first book to combine both the visualization and manipulation of sound technologies in one comprehensive volume Presents the basic concepts using simple one dimensional cases and then extends the concept to three dimensional cases, enabling easier understanding of the fundamental concepts through the use of minimum mathematics Provides a solid understanding of associated physics as well as mathematical concepts for understanding the technologies, addressing diffraction problems in an integrated format by using Kirchhoff-Helmholtz integral equation Uses extensive examples demonstrating the benefits and drawbacks of various applications, including beamforming and acoustic holography A valuable resource forpost/graduate students, acoustic engineers, audio and noise control system developers




Acoustic Array Systems


Book Description

Presents a unified framework of far-field and near-field array techniques for noise source identification and sound field visualization, from theory to application. Acoustic Array Systems: Theory, Implementation, and Application provides an overview of microphone array technology with applications in noise source identification and sound field visualization. In the comprehensive treatment of microphone arrays, the topics covered include an introduction to the theory, far-field and near-field array signal processing algorithms, practical implementations, and common applications: vehicles, computing and communications equipment, compressors, fans, and household appliances, and hands-free speech. The author concludes with other emerging techniques and innovative algorithms. Encompasses theoretical background, implementation considerations and application know-how Shows how to tackle broader problems in signal processing, control, and transudcers Covers both farfield and nearfield techniques in a balanced way Introduces innovative algorithms including equivalent source imaging (NESI) and high-resolution nearfield arrays Selected code examples available for download for readers to practice on their own Presentation slides available for instructor use A valuable resource for Postgraduates and researchers in acoustics, noise control engineering, audio engineering, and signal processing.




Least-Squares Finite Element Methods


Book Description

Since their emergence, finite element methods have taken a place as one of the most versatile and powerful methodologies for the approximate numerical solution of Partial Differential Equations. These methods are used in incompressible fluid flow, heat, transfer, and other problems. This book provides researchers and practitioners with a concise guide to the theory and practice of least-square finite element methods, their strengths and weaknesses, established successes, and open problems.




Springer Handbook of Acoustics


Book Description

Acoustics, the science of sound, has developed into a broad interdisciplinary field encompassing the academic disciplines of physics, engineering, psychology, speech, audiology, music, architecture, physiology, neuroscience and others. Here is an unparalleled modern handbook reflecting this richly interdisciplinary nature edited by one of the acknowledged masters in the field, Thomas Rossing. Researchers and students benefit from the comprehensive contents spanning: animal acoustics including infrasound and ultrasound, environmental noise control, music and human speech and singing, physiological and psychological acoustics, architectural acoustics, physical and engineering acoustics, medical acoustics and ocean acoustics. The Springer Handbook of Acoustics reviews the most important areas of acoustics, with emphasis on current research. The authors of the various chapters are all experts in their fields. Each chapter is richly illustrated with figures and tables. The latest research and applications are incorporated throughout, e.g. computer recognition and synthesis of speech, physiological acoustics, psychological acoustics, thermoacoustics, diagnostic imaging and therapeutic applications and acoustical oceanography. This new edition of the Handbook features over 11 revised and expanded chapters, new illustrations and two new chapters covering microphone arrays, acoustic metamaterials and acoustic emission. These improvements will make the handbook even more useful as a reference and a guide for researchers and students in every branch of acoustics. Praise for the first edition: "This treatise is a successful attempt to cover in one book the diverse field of acoustics, which ranges from physics to music and from formal mathematics to technological applications. ... It is this reviewer's opinion that a handbook like Rossing's, which covers the whole field of acoustics, serves a real purpose because it not only gives one a chance to see how one's specialty is covered but it also permits one to make a quick survey of other acoustical areas." (Leo Beranek, American Journal of Physics, Vol. 77 (12), December, 2009) "The Springer Handbook of Acoustics falls into that exceptional list. ...every physics department should have a copy available." (John L. Hubisz, The Physics Teacher, Vol. 48, March, 2010) "This handbook is an excellent addition to the acoustics literature. ... The handbook nicely covers both basics and advances in several areas of acoustics. Several chapters provide good mathematical depth, making the handbook useful as a research and technical resource. ...Overall, a very useful educational and research resource. Summing Up: Recommended. Upper-division undergraduates through professionals." (M. G. Prasad, CHOICE, Vol. 45 (5), January, 2008) "This book covers a wide range of topics and the inclusion of musical acoustics, computer and electronic music appeal to me (singer, song-writer, performer and recording studio co-owner). This handbook is probably well suited for an undergraduate-level introduction to an acoustics course. ... The wide range of topics, inclusion of music-related chapters, eye-pleasing presentations and other useful features make this a very good book to have on your shelf." (Tim Casey, International Journal of Acoustics and Vibration, Vol. 13 (1), 2008) "The Springer Handbook of Acoustics comprises 28 chapters written by 33 authors. The Handbook of Acoustics is useful as a source book for anyone who needs or wants to become familiar with the jargon and issues related to a specific subfield of acoustics ... ." (Robert I. Odom, Siam Review, Vol. 50 (3), 2008) The Springer Handbook of Acoustics reviews the most important areas of acoustics, with emphasis on current research. The authors of the various chapters are all experts in their fields. Each chapter is richly illustrated with figures and tables. The latest research and applications are incorporated throughout, e.g. computer recognition and synthesis of speech, physiological acoustics, psychological acoustics, thermoacoustics, diagnostic imaging and therapeutic applications and acoustical oceanography. This new edition of the Handbook features over 13 revised and expanded chapters, new illustrations and 3 new chapters covering microphone arrays, acoustic metamaterials and acoustic emission. These improvements will make the handbook even more useful as a reference and a guide for researchers and students in every branch of acoustics.




Computational Acoustics of Noise Propagation in Fluids - Finite and Boundary Element Methods


Book Description

The book provides a survey of numerical methods for acoustics, namely the finite element method (FEM) and the boundary element method (BEM). It is the first book summarizing FEM and BEM (and optimization) for acoustics. The book shows that both methods can be effectively used for many other cases, FEM even for open domains and BEM for closed ones. Emphasis of the book is put on numerical aspects and on treatment of the exterior problem in acoustics, i.e. noise radiation.







Vibration and Structural Acoustics Analysis


Book Description

Vibration and structural acoustics analysis has become an essential requirement for high-quality structural and mechanical design in order to assure acoustic comfort and the integrity, reliability and fail-safe behavior of structures and machines. The underlying technologies of this field of multidisciplinary research are evolving very fast and their dissemination is usually scattered over different and complementary scientific and technical publication means. In order to make it easy for developers and technology end-users to follow the latest developments and news in the field, this book collects into a single volume selected, extended, updated and revised versions of papers presented at the Symposium on Vibration and Structural Acoustics Analysis, coordinated by J. Dias Rodrigues and C. M. A. Vasques, which was organised as part of the 3rd International Conference on Integrity, Reliability & Failure (IRF’2009), co-chaired by J. F. Silva Gomes and Shaker A. Meguid, held at the Faculty of Engineering of the University of Porto, Portugal, 20-24 July 2009. These papers where chosen from the more than 60 papers presented at the conference symposium. Written by experienced practitioners and researchers in the field, this book brings together recent developments in the field, spanning across a broad range of themes: vibration analysis, analytical and computational structural acoustics and vibration, material systems and technologies for noise and vibration control, vibration-based structural health monitoring/evaluation, machinery noise/vibration and diagnostics, experimental testing in vibration and structural acoustics, applications and case studies in structural acoustics and vibration. Each chapter presents and describes the state of the art, presents current research results and discusses the need for future developments in a particular aspect of vibration and structural acoustics analysis. The book is envisaged to be an appealing text for newcomers to the subject and a useful research study tool for advanced students and faculty members. Practitioners and researchers may also find this book a one-stop reference that addresses current and future challenges in this field. The variety of case studies is expected to stimulate a holistic view of sound and vibration and related fields and to appeal to a broad spectrum of engineers such as the ones in the mechanical, aeronautical, aerospace, civil and electrical communities.




Advanced Finite Element Methods with Applications


Book Description

Finite element methods are the most popular methods for solving partial differential equations numerically, and despite having a history of more than 50 years, there is still active research on their analysis, application and extension. This book features overview papers and original research articles from participants of the 30th Chemnitz Finite Element Symposium, which itself has a 40-year history. Covering topics including numerical methods for equations with fractional partial derivatives; isogeometric analysis and other novel discretization methods, like space-time finite elements and boundary elements; analysis of a posteriori error estimates and adaptive methods; enhancement of efficient solvers of the resulting systems of equations, discretization methods for partial differential equations on surfaces; and methods adapted to applications in solid and fluid mechanics, it offers readers insights into the latest results.