Construction and Testing of a Modern Acoustic Impedance Tube


Book Description

The acoustic impedance of a material describes its reflective and absorptive properties. Acoustic impedance may be measured in a wide variety of ways. This thesis describes the construction and testing of an acoustic impedance measurement tube which employs modem Fourier Transform techniques. Two methods are employed for acoustic impedance measurement using this apparatus. One technique uses a two-microphone continuous excitation method and the other uses a single microphone transient excitation method. Simple acoustic theory is used to derive equations for both methods. MATLAB computer programs are developed using these equations, to provide graphical results of acoustic impedance measurements over a frequency range for a given material, from raw data. A procedure is subsequently developed for using this apparatus using to make acoustic impedance measurements. The performance of this device is evaluated by making measurements utilizing both methods on three sample materials and also with the end of the tube open to the atmosphere (referred to as an open tube measurement). The open tube measurements are compared with theoretical values. The results using both approaches compared favorably with the open tube theoretical values. Additionally both approaches agreed reasonably well with each other for the three sample materials. Performance at frequencies below 500 Hz, however, yielded deficient results, indicating a need for development of a filter for better accuracy.




Wiley Survey of Instrumentation and Measurement


Book Description

In-depth coverage of instrumentation and measurement from the Wiley Encyclopedia of Electrical and Electronics Engineering The Wiley Survey of Instrumentation and Measurement features 97 articles selected from the Wiley Encyclopedia of Electrical and Electronics Engineering, the one truly indispensable reference for electrical engineers. Together, these articles provide authoritative coverage of the important topic of instrumentation and measurement. This collection also, for the first time, makes this information available to those who do not have access to the full 24-volume encyclopedia. The entire encyclopedia is available online-visit www.interscience.wiley.com/EEEE for more details. Articles are grouped under sections devoted to the major topics in instrumentation and measurement, including: * Sensors and transducers * Signal conditioning * General-purpose instrumentation and measurement * Electrical variables * Electromagnetic variables * Mechanical variables * Time, frequency, and phase * Noise and distortion * Power and energy * Instrumentation for chemistry and physics * Interferometers and spectrometers * Microscopy * Data acquisition and recording * Testing methods The articles collected here provide broad coverage of this important subject and make the Wiley Survey of Instrumentation and Measurement a vital resource for researchers and practitioners alike




Impedance Spectroscopy


Book Description

Impedance Spectroscopy is a powerful measurement method used in many application fields such as electrochemistry, material science, biology and medicine, semiconductor industry and sensors. Using the complex impedance at various frequencies increases the informational basis that can be gained during a measurement. It helps to separate different effects that contribute to a measurement and, together with advanced mathematical methods, non-accessible quantities can be calculated. This book covers new advances in the field of impedance spectroscopy including fundamentals, methods and applications. It releases scientific contributions from the International Workshop on Impedance Spectroscopy (IWIS) as extended chapters including detailed information about recent scientific research results. The book includes typically subsections on: Fundamental of Impedance Spectroscopy Bio impedance Techniques and Applications Impedance Spectroscopy for Energy Storage Systems Sensors Based on Impedance Spectroscopy Measurement systems Excitation Signals Modeling Parameter extraction




Physical Acoustics and Metrology of Fluids


Book Description

The interaction of sound waves with the medium through which they pass can be used to investigate the thermophysical properties of that medium. With the advent of modern instrumentation, it is now possible to determine the speed and absorption of sound with extremely high precision and, through the dependence of those quantities on variables like temperature, pressure, and frequency to gain a sensitive measure of one or more properties of fluid. This has led to renewed interest in such measurements and in the extraction of thermophysical properties of gases and liquids there from. Physical Acoustics and Metrology of Fluids describes both how to design experiments to achieve the highest possible accuracy and how to relate the quantities measured in those experiments to the thermophysical properties of the medium. A thorough theoretical examination of the alternative experimental methods available is designed to guide the experimentalist toward better and more accurate methods. This theoretical analysis is enhanced and complemented by an in-depth discussion of practical experimental techniques and the problems inherent within them. Bringing together the fields of thermodynamics, kinetic theory, fluid mechanics, and theoretical acoustics, plus a wealth of information about practical instruments, this book represents an essential reference on the design and execution of valuable experiments in fluid metrology and physical acoustics.










Comprehensive Biomaterials II


Book Description

Comprehensive Biomaterials II, Second Edition, Seven Volume Set brings together the myriad facets of biomaterials into one expertly-written series of edited volumes. Articles address the current status of nearly all biomaterials in the field, their strengths and weaknesses, their future prospects, appropriate analytical methods and testing, device applications and performance, emerging candidate materials as competitors and disruptive technologies, research and development, regulatory management, commercial aspects, and applications, including medical applications. Detailed coverage is given to both new and emerging areas and the latest research in more traditional areas of the field. Particular attention is given to those areas in which major recent developments have taken place. This new edition, with 75% new or updated articles, will provide biomedical scientists in industry, government, academia, and research organizations with an accurate perspective on the field in a manner that is both accessible and thorough. Reviews the current status of nearly all biomaterials in the field by analyzing their strengths and weaknesses, performance, and future prospects Covers all significant emerging technologies in areas such as 3D printing of tissues, organs and scaffolds, cell encapsulation; multimodal delivery, cancer/vaccine - biomaterial applications, neural interface understanding, materials used for in situ imaging, and infection prevention and treatment Effectively describes the many modern aspects of biomaterials from basic science, to clinical applications