Acoustics

This book presents theoretical and experimental investigations of mechanical behavior of solids under shock loading and highlights a multi-scale exchange process of energy and momentum between meso and macroscopic hierarchy. It also widely covers experimental approaches for the multi-scale response of solids to impacts including uniaxial strain conditions and high-velocity penetration processes.The content comprises two parts. The first part overviews modeling and theory of dynamically deformed solids from the multi-scale point of view. The second part describes experimental characterization of shock-induced solids and experimental probing of mesostructured and mesoscale dynamic processes in solids. The theory presented in the first part is then verified as it is compared with i) experiments of shock loading into different kinds of solids and ii) probed microstructure of post-shocked specimens by scanning electron microscopy, transmission electron microscopy and optical microscopy.The text is written on the basis of author's lectures at universities and thus is concisely described for postgraduate students. It is also useful for researchers who work on the theory of multi-scale mechanics of solids and engineers who work on testing materials under dynamic loading.

This book presents a novel framework design for the next generation Marine Wireless Communication Networks (MWCNs). The authors first provide an overview of MWCNs, followed by a discussion of challenges in the design and development of MWCNs in support of a diversity of marine services such as real-time marine monitoring, offshore oil exploration, drilling, marine tourism and fishing. The authors then propose cross layer networking solutions to achieve a high performance modern MWCN that enables efficient and reliable data transmissions under hostile marine environment, which include the network deployment, the physical layer channel coding, intelligent network access and resource management, and learning-based opportunistic routing. Finally, the authors summarize the book and present some open issues that will lead to new research directions in the next generation MWCNs.

This book consists of selected peer-reviewed papers from the 2nd International Seminar on Aeronautics and Energy (ISAE 2022) focusing on the theme to revive the aviation industry post-COVID-19 pandemic. The topics discussed in this book include aircraft design and optimization, computational fluid dynamics (CFD) simulation and experimental aerodynamics, aircraft structure and aeroelasticity, guidance control and navigation, aircraft manufacturing and health monitoring avionics and system integration of UAV/drones, SITL AND HITL application on drones, rockets and missile, industrial wind engineering, green fuel and aviation sustainability, and aviation management. This book is a valuable resource for academicians and industry players in the field of aviation and sustainability.

This book basically involves the study of flight parameters, wing beat frequency, moment of inertia, and wing movements for developing various aerodynamic forces which have been calculated. The book is intended for biologists, physicists, nanotechnologists, and aerospace engineers. Resilin, an elastic polymer (4 ¿) which is present at the base of insect, plays a major role in Neurogenic and Myogenic insect flyers and influences the physiology of flight muscles. Leading edge vortex (LEV) is a special feature of insect flight. Insect wings have stalling angle above 60 degrees as compared to a man-made aeroplane stalling angle which is 16 degree. Reynolds number, the knowledge of LEV, and detailed study of moment of inertia help in developing flapping flexible wings for micro-aerial-vehicles. This book serves as an interface between biologists and engineers interested to develop biomimicking micro-aerial-vehicles. The contents of this book is useful to researchers and professionals alike.

The nature of sound is, nowadays, well known and understood so that sound could be synthetically described like the propagation of vibration in elastic media.¿Sound waves propagate as longitudinal waves, transverse waves, or in mixed modes in different media. The development of applications related to the proper management of the information connected with sound waves. This is the case of so-called acoustic emission. This book introduces the basics of sound waves, their types, propagation in different modes, velocities, and other properties It also introduces the basics of acoustic emission and the different sources of acoustic emission. This book delivers different propagation modes, their significance, and the attenuation and distortion of acoustic waves. One of the overlooked applications of acoustic emission, the acousto-ultrasonic approach is introduced and discussed with practical applications.

This book is a study of the workings of dynamic loudspeakers and dynamically forced vibration. With its wealth of practical observations and real-life examples, this work will prove invaluable to the practicing motor design or loudspeaker design engineer, as well as researchers and students in electroacoustics.The book is based on a lifetime's accumulated knowledge by acclaimed speaker designer William H. (Bill) Watkins. It differs from the usual tone of most technical books on this subject by initially presenting, and analyzing in full, the function of each key parameter of a reference dynamic loudspeaker. Each parameter's value is then calculated and also confirmed via lab measurements to vividly illustrate all energy-transduction facets of loudspeaker operation and the forced vibration. This presentation style makes the analysis both more engaging, intuitive, and easier to comprehend compared to most previous works in the field.The principles of this book apply toall direct reciprocating motors, not just those in a dynamic loudspeaker. Unique to the book is an entire chapter dedicated to the discussion of back-EMF voltage, discussed from several technical points of view and analyzed in depth as related to the dynamic transfer of energy between the mechanical and electrical domains. Another unique feature is a detailed discussion of Watkins' patented dual-motor concept to achieve high dynamic speaker performance in the region of its low-frequency resonance.

The following topics are presented in this book:introduction to waves and their propertiesacoustic waveshuman acoustics and phonometric systemsroom acoustics and hints of building acoustic design

This book presents how to apply recent machine learning (deep learning) methods for the task of speech quality prediction. The author shows how recent advancements in machine learning can be leveraged for the task of speech quality prediction and provides an in-depth analysis of the suitability of different deep learning architectures for this task. The author then shows how the resulting model outperforms traditional speech quality models and provides additional information about the cause of a quality impairment through the prediction of the speech quality dimensions of noisiness, coloration, discontinuity, and loudness.

This volume presents the proceedings of the Asia-Pacific Vibration Conference (APVC) 2019, "Vibration Engineering for a Sustainable Future," emphasizing work devoted to experimental methods and verification. The APVC is one of the larger conferences held biannually with the intention to foster scientific and technical research collaboration among Asia-Pacific countries. The APVC provides a forum for researchers, practitioners, and students from, but not limited to, areas around the Asia-Pacific countries in a collegial and stimulating environment to present, discuss and disseminate recent advances and new findings on all aspects of vibration and noise, their control and utilization. All aspects of vibration, acoustics, vibration and noise control, vibration utilization, fault diagnosis and monitoring are appropriate for the conference, with the focus this year on the vibration aspects in dynamics and noise & vibration. This 18th edition of the APVC was held in November 2019 in Sydney, Australia. The previous seventeen conferences have been held in Japan ('85, '93, '07), Korea ('87, '97, '13), China ('89, '01, '11, '17), Australia ('91, '03), Malaysia ('95, '05), Singapore ('99), New Zealand ('09) and Vietnam ('15).

This book highlights the theories and applications of quantum acoustical imaging which can be considered as a part of quantum technology. It starts with the theories and background principles of this new field in depth.The examples of some present forms of available acoustical imaging which can be considered as quantum acoustical imaging are given such as ultrasonics in the terahertz range with the use of optical transducers for producing terahertz ultrasound and the theory of sound amplification by stimulated emission of radiation (SASER) and principles based on terahertz ultrasound. The SASER transducer is described, followed by the applications of SASER.Other examples of quantum acoustical imaging are the atomic force acoustic microscope (AFAM) and the ultrasonic force microscope. The author's personal inventions of quantum acoustical imaging are a system based on phonons entanglement based on the quantum property of phonons entanglement and the quantum ultrasound diffraction tomography system.The advantage of quantum acoustical imaging is the defeat of the classical Rayleigh image resolution limit. An unique feature of this book is that it has gone in depth into the quantum theories of acoustical imaging such as phonons entanglement,,superposition principle and the application of transport theory.Quantum microphones and quantum transducers are also introduced with a final chapter on quantum image processing.

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.

This book introduces sonar system and acoustic channel model, average energy channel, coherent multipath channel, the theoretical basis for the stochastic time-varying space-variant channel, slowly time-varying coherent multipath channel, and reverberation channel. Based on the basic theory of underwater acoustic channels and the various characteristics of the marine acoustic environment factor, this textbook aims to help students understand the impact of the marine acoustic channel on the sonar system. It helps students to grasp underwater acoustic signal processing principles and obtain the ability to solve practical problems in underwater acoustic channel engineering. Finally, it aims at laying a foundation for the further sonar system design. This textbook is recommended for graduate or undergraduate students in the field of sonar signal processing, underwater acoustic engineering, as well as some related subjects of marine technology.

This book presents a technical solution to ensuring the noise immunity of navigation systems in civil aviation aircrafts at the stages of their terminal procedures. It highlights instrumental precision approaches to landing and landing in automatic mode using satellite and inertial radio navigation systems and ground-based augmentation used as the primary means, in accordance with the ICAO requirements. The book is intended for engineering and technical specialists engaged in the development, manufacture and operation of on-board radio electronic systems of aircrafts and ground-based radio engineering support for flights, as well as graduate students and senior students of radio engineering specialties. It is also useful for professionals whose activities are related to air traffic control.

This book provides an introduction to Acoustic Emission Testing and its applications to different materials like concrete, steel, ceramics, geotechnical materials, polymers, biological structures and wood. Acoustic Emission Techniques (AET) techniques have been studied in engineering for a long time. The techniques are applied more and more to practical investigations and are more and more standardized in codes. This is because the degradation of structures due to ageing urgently demand for maintenance and rehabilitation of structures in service. It results in the need for the development of advanced and efficient inspection techniques. In mechanical engineering and concerning the monitoring of machines and mechanical components, AE is a widely accepted observing deterioration in the frame of structural health monitoring. The advantages of AE like sensitivity, damage localization potential, non-intrusive nature as well as developments in signal analysis and data transmission allow applications that could not be considered decades ago.As such, AE techniques draw great attention to diagnostic applications and in material testing. This book covers all levels from the description of AE basics for AE beginners (level of a student) to sophisticated AE algorithms and applications to real large-scale structures as well as the observation of the cracking process in laboratory specimen to study fracture processes. This book has proved its worth over the past twelve years. Now in its second edition, it will be a resource that sets the standard and equips readers for the future. All chapters from the 1st edition have been updated and rewritten and eight extra chapters (e.g also regarding AE tomography, AE in plate-like structures and AE for investigations of hardening of fresh concrete) have been added.

What is the future of CMOS? Sustaining increased transistor densities along the path of Moore's Law has become increasingly challenging with limited power budgets, interconnect bandwidths, and fabrication capabilities. In the last decade alone, transistors have undergone significant design makeovers; from planar transistors of ten years ago, technological advancements have accelerated to today's FinFETs, which hardly resemble their bulky ancestors. FinFETs could potentially take us to the 5-nm node, but what comes after it? From gate-all-around devices to single electron transistors and two-dimensional semiconductors, a torrent of research is being carried out in order to design the next transistor generation, engineer the optimal materials, improve the fabrication technology, and properly model future devices. We invite insight from investigators and scientists in the field to showcase their work in this Special Issue with research papers, short communications, and review articles that focus on trends in micro- and nanotechnology from fundamental research to applications.

Many of the significant issues in fluid dynamics occur at interfaces, that is, at the boundaries between differing fluids or between fluids and solids. These issues are important in areas ranging from aircraft flight, to the flow of blood in the heart, to chemical vapour deposition. The subject is an area of active research and development, owing to improved analytical, experimental, and computational techniques. This book describes research and applications in interfacial fluid dynamics and stability. It is organized around five topics: Benard and thermocapillary instabilities, shear and pressure induced instabilities, waves and dispersions, multiphase systems, and complex flows. Chapters have been contributed by internationally recognized experts, both theoreticians and experimentalists. Because of the range and importance of topics discussed, this book will interest a broad audience of graduate students and researchers in mechanical, aerospace, materials, and chemical engineering, as well as in applied mathematics and physics.

In the last few decades the applications of piezoelectrics to sensors have witnessed a dramatic acceleration and new devices and materials have been discovered. Some of the highlights include electrostrictive materials for positioners, relaxor-normal ferroelectric single crystals with very high electromechanical couplings for medical transducers, thin/thick PZT films for microelectromechanical systems, starting from a sophisticated chemical technology, and multilayer actuators fabricated by a cofiring technique. All will make a remarkable industrial impact in the 21st century.