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Model-Based Processing for Underwater Acoustic Arrays
Books NEW Book from ASA Press ASA Press is a meritorious imprint of the Acoustical Society of America in collaboration with the major international publisher Springer Science + Business Media. All new books that are published with the ASA Press imprint will be announced in Acoustics Today. Individuals who have ideas for books should feel free to contact the ASA Publications Office to discuss their ideas. Model-Based Processing can be recursive either in space or time, depending on the for Underwater Acoustic application.This is done for three reasons. First, the Kalman Arrays filter provides a natural framework for the inclusion of phys- Author: Edmund J. Sullivan ical models in a processing scheme. Second, it allows poorly ISBN: 978-3-319-17556-0 known model parameters to be jointly estimated along with Pages: 113 pp., 25 illus., the quantities of interest. This is important, since in cer- 14 illus. in color tain areas of array processing already in use, such as those Available formats: based on matched-field processing, the so-called mismatch Softcover, $54.99, problem either degrades performance or, indeed, prevents eBook, MyCopy any solution at all. Thirdly, such a unification provides a for- Publication Date: 2015 mal means of quantifying the performance improvement. Publisher: Springer The term model-based will be strictly defined as the use of International Publishing physics-based models as a means of introducing a priori in- formation. This leads naturally to viewing the method as a Bayesian processor. Short expositions of estimation theory This monograph presents a unified approach to model- and acoustic array theory are presented, followed by a pre- based processing for underwater acoustic arrays. -
HP-2 Acoustic Design Guide
ACOUSTIC PRODUCT FAMILY Specifying Design Guide Our in-house, custom 7 STEPS TO SPECIFY Robust Examples including APPLICATION DRAWINGS Informative intro to the world of ACOUSTICS Table of Contents INTRODUCTION � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 3 STEPS OVERVIEW � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 4 MATERIAL TABLE � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 5 REVERBERATION TIME TABLE � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 6 PRODUCT TABLE � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 8 EXAMPLE 1 � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 9 EXAMPLE 2 � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �12 WORKSHEET � � � � � � � � � � � � � � � -
Physics of Music PHY103 Lab Manual
Physics of Music PHY103 Lab Manual Lab #6 – Room Acoustics EQUIPMENT • Tape measures • Noise making devices (pieces of wood for clappers). • Microphones, stands, preamps connected to computers. • Extra XLR microphone cables so the microphones can reach the padded closet and hallway. • Key to the infamous padded closet INTRODUCTION One important application of the study of sound is in the area of acoustics. The acoustic properties of a room are important for rooms such as lecture halls, auditoriums, libraries and theatres. In this lab we will record and measure the properties of impulsive sounds in different rooms. There are three rooms we can easily study near the lab: the lab itself, the “anechoic” chamber (i.e. padded closet across the hall, B+L417C, that isn’t anechoic) and the hallway (that has noticeable echoes). Anechoic means no echoes. An anechoic chamber is a room built specifically with walls that absorb sound. Such a room should be considerably quieter than a normal room. Step into the padded closet and snap your fingers and speak a few words. The sound should be muffled. For those of us living in Rochester this will not be a new sensation as freshly fallen snow absorbs sound well. If you close your eyes you could almost imagine that you are outside in the snow (except for the warmth, and bizarre smell in there). The reverberant sound in an auditorium dies away with time as the sound energy is absorbed by multiple interactions with the surfaces of the room. In a more reflective room, it will take longer for the sound to die away and the room is said to be 'live'. -
Vern Oliver Knudsen Papers LSC.1153
http://oac.cdlib.org/findaid/ark:/13030/kt109nc33w No online items Finding Aid for the Vern Oliver Knudsen Papers LSC.1153 Finding aid updated by Kelly Besser, 2021. UCLA Library Special Collections Finding aid last updated 2021 March 29. Room A1713, Charles E. Young Research Library Box 951575 Los Angeles, CA 90095-1575 [email protected] URL: https://www.library.ucla.edu/special-collections Finding Aid for the Vern Oliver LSC.1153 1 Knudsen Papers LSC.1153 Contributing Institution: UCLA Library Special Collections Title: Vern Oliver Knudsen papers Creator: Knudsen, Vern Oliver, 1893-1974 Identifier/Call Number: LSC.1153 Physical Description: 28.25 Linear Feet(57 document boxes, and 8 map folders) Date (inclusive): circa 1922-1980 Abstract: Vern Oliver Knudsen (1893-1974) was a professor in the Department of Physics at UCLA before serving as the first dean of the Graduate Division (1934-58), Vice Chancellor (1956), Chancellor (1959). He also researched architectural acoustics and hearing impairments, developed the audiometer with Isaac H. Jones, founded the Acoustical Society of America (1928), organized and served as the first director of what is now the Naval Undersea Research and Development Center in San Diego, and worked as a acoustical consultant for various projects including the Hollywood Bowl, the Dorothy Chandler Pavilion, Schoenberg Hall, the United Nations General Assembly building, and a variety of radio and motion picture studios. The collection consists of manuscripts, correspondence, galley proofs, and other material related to Knudsen's professional activities. The collection also includes the papers of Leo Peter Delsasso, John Mead Adams, and Edgar Lee Kinsey. -
Martinho, Claudia. 2019. Aural Architecture Practice: Creative Approaches for an Ecology of Affect
Martinho, Claudia. 2019. Aural Architecture Practice: Creative Approaches for an Ecology of Affect. Doctoral thesis, Goldsmiths, University of London [Thesis] https://research.gold.ac.uk/id/eprint/26374/ The version presented here may differ from the published, performed or presented work. Please go to the persistent GRO record above for more information. If you believe that any material held in the repository infringes copyright law, please contact the Repository Team at Goldsmiths, University of London via the following email address: [email protected]. The item will be removed from the repository while any claim is being investigated. For more information, please contact the GRO team: [email protected] !1 Aural Architecture Practice Creative Approaches for an Ecology of Affect Cláudia Martinho Goldsmiths, University of London PhD Music (Sonic Arts) 2018 !2 The work presented in this thesis has been carried out by myself, except as otherwise specified. December 15, 2017 !3 Acknowledgments Thanks to: my family, Mazatzin and Sitlali, for their support and understanding; my PhD thesis’ supervisors, Professor John Levack Drever and Dr. Iris Garrelfs, for their valuable input; and everyone who has inspired me and that took part in the co-creation of this thesis practical case studies. This research has been supported by the Foundation for Science and Technology fellowship. Funding has also been granted from the Department of Music and from the Graduate School at Goldsmiths University of London, the arts organisations Guimarães Capital of Culture 2012, Invisible Places and Lisboa Soa, to support the creation of the artworks presented in this research as practical case studies. -
Reverberation and the Art of Architectural Acoustics
Sabine and reverberation 11/29/02 11:21 AM Reverberation and the Art of Architectural Acoustics © 2002 Robert Sekuler (revised) In 1895 Harvard University, that other school situated on the Charles River, opened its Fogg Art Museum. This wonderful building, still much used today, contained an equally wonderful, large lecture hall. Audiences flocked in, eager to experience intellectual enlightenment in beautiful new surroundings. But there was a large, ugly fly in this intellectual ointment: No one could understand any of the lectures that were given in Fogg lecture hall. And it wasn't because the lectures were too esoteric, or because the lecturers mumbled into their beards, or because the students were too distracted. The problem was acoustics and hearing. For help, Harvard turned to one of its own, Wallace Clement Sabine (photo), then a 27 year-old Assistant Professor of Physics. To that point in his career, Sabine had distinguished himself primarily through his teaching; research productivity was not his strongest suit. Even though Sabine had not previously worked with this sort of problem, his writings show that he was a remarkably quick study and a truly dedicated scientist. His published work also provides a model of good, clear scientific prose. After diagnosing and then solving Harvard's problem with the Fogg lecture room, Sabine devoted the rest of his career to the new field that he had virtually created in the process: architectural acoustics. First, Sabine noted that when anyone spoke in the Fogg Museum lecture room, even at normal conversational levels, the sound of his or her voice remained audible in the room for several seconds thereafter. -
The Room Acoustics of Large Spaces
ROOMROOM ACOUSTICSACOUSTICS OFOF LARGELARGE SPACESSPACES TheThe TalaskeTalaske Group,Group, inc.inc. The Room Acoustics of Large Spaces Presented by: Rick Talaske The Talaske Group, inc. Oak Park, IL – U.S.A. ASA Tutorial Cancun, Mexico The photos of all projects are designed by The Talaske Group, inc. Presented to the Acoustical Society of America – Cancun, Mexico 02 December 2002 ROOMROOM ACOUSTICSACOUSTICS OFOF LARGELARGE SPACESSPACES TheThe TalaskeTalaske Group,Group, inc.inc. Acoustically speaking: What is a “Large” Room It is my pleasure to present this discussion in Cancun regarding the acoustics of large rooms. Generally, this topic is what the public thinks of when they hear the word “acoustics”. This is because of their experiences in churches, theatres and music halls. I hope to better your understanding about this interesting topic. Es un placer de estar aqui en Cancun y al al vez hacer un presentacion sobre la acustica en grandes espacios. Generalmente, la gente cada vez que se menciona la palabra “acusticaq”, la relacionan con iglesias, teatros ysalas musicales. Espero de que en esta presentacion, ustedes se lleven un mejor entendimiento del concepto de acustica. Presented to the Acoustical Society of America – Cancun, Mexico 02 December 2002 ROOMROOM ACOUSTICSACOUSTICS OFOF LARGELARGE SPACESSPACES TheThe TalaskeTalaske Group,Group, inc.inc. Acoustically speaking: What is a “Large” Room In this paper, a large room: • Schroeder’s Frequency is less than 50 Hz •fc = 2000*SR ( T60/V ) •fc is below the voice and music bandwidth. • Comb filtering is a lesser consideration. • Un espacio grande es un cuarto con muchas resonancias normales. Hay tantas resonancias que finalmente no son tan importantes. -
Room Acoustics Education in Interior Architecture Programs: a Course Structure Proposal
Room acoustics education in interior architecture programs: A course structure proposal Kitapci, Kivanc1 Çankaya University Mimarlık Fakültesi, İç Mimarlık Bölümü. Çukurambar Mah. Öğretmenler Cad. No: 14, 06530 Çankaya, Ankara, Türkiye ABSTRACT Soundscape research alters the notion of room acoustics from a physical phenomenon to a new multidisciplinary approach that concerns human perception of the acoustic environment, in addition to the physical calculations and measurements. Many interior architecture programs include courses that specifically focus on room acoustics. Although a brief introduction to the technical aspects of room acoustics is considered mandatory, the current course structure does not deliver sufficient information on the human perception of the acoustic environment. Therefore, the aim of the study is to reconsider the structure of room acoustic courses and present a brand- new room acoustics course structure proposal for the interior architecture programs. The study consists of two main phases. In the first phase, a database of all courses that include various topics on room acoustics is prepared through examination of the course descriptions of all undergraduate and graduate interior architecture programs in Turkey. In the second phase, the revisions to the current state of the room acoustics course structures are advised through an in-depth systematic literature review on the research area of soundscapes. Preliminary results and the initial course structure model will be presented at the conference. Keywords: Acoustic education, Soundscape, Interior architecture I-INCE Classification of Subject Number: 07 1. INTRODUCTION Since the beginning of the 20th century, vision-centred approaches dominate the higher-education curriculums of design disciplines such as architecture, interior architecture, industrial design, and city and regional planning. -
Principles of Acoustics - Andres Porta Contreras, Catalina E
FUNDAMENTALS OF PHYSICS – Vol. I - Principles Of Acoustics - Andres Porta Contreras, Catalina E. Stern Forgach PRINCIPLES OF ACOUSTICS Andrés Porta Contreras Department of Physics, Universidad Nacional Autónoma de México, México Catalina E. Stern Forgach Department of Physics, Universidad Nacional Autónoma de México, México Keywords: Acoustics, Ear, Diffraction, Doppler effect, Music, Sound, Standing Waves, Ultrasound, Vibration, Waves. Contents 1. Introduction 2. History 3. Basic Concepts 3.1. What is Sound? 3.2. Characteristics of a Wave 3.3. Qualities of Sound 3.3.1. Loudness 3.3.2. Pitch 3.3.3. Timbre 3.4. Mathematical Description of a Pure Sound Wave 3.5. Doppler Effect 3.6. Reflection and Refraction 3.7. Superposition and Interference 3.8. Standing Waves 3.9. Timbre, Modes and Harmonics 3.10. Diffraction 4. Physiological and Psychological Effects of Sound 4.1. Anatomy and Physiology of Hearing. 4.1.1. Outer Ear 4.1.2. Middle Ear 4.1.3. Inner Ear 5. ApplicationsUNESCO – EOLSS 5.1. Ultrasound 5.2. Medicine 5.3. Noise Control 5.4. MeteorologySAMPLE and Seismology CHAPTERS 5.5. Harmonic Synthesis 5.6. Acoustical Architecture and Special Building Rooms Design 5.7. Speech and Voice 5.8. Recording and Reproduction 5.9. Other Glossary Bibliography Biographical Sketches ©Encyclopedia of Life Support Systems (EOLSS) FUNDAMENTALS OF PHYSICS – Vol. I - Principles Of Acoustics - Andres Porta Contreras, Catalina E. Stern Forgach Summary The chapter begins with a brief history of acoustics from Pythagoras to the present times. Then the main physical and mathematical principles on acoustics are reviewed. A general description of waves is given first, then the characteristics of sound and some of the most common phenomena related to acoustics like echo, diffraction and the Doppler effect are discussed. -
Paper One the Standing Wave Problem
LeadingEdge Systematic Approach Room Acoustic Principles - Paper One The Standing Wave Problem Sound quality problems caused by poor room acoustics. We all recognise that room acoustics can cause sound quality problems. But often the issues are not clearly described or discussed. Here we will cover some important considerations and principles of room acoustics problems. Treating your room should not be done in isolation from all the other system building considerations. Your thoughts about room acoustics treatment should be in conjunction with your requirements for mains, supports, system electronics, speakers and cables etc. None of these should be dealt with in isolation, and with regards to room acoustics it’s particularly important to be aware of some of the interactive nature of room acoustics, and other systematic faults. For example, a boomy bass could be caused by a room mode, but equally it could be caused by bass feedback from a wall and up into your system through the mains leads. If it’s your mains cables feeding back vibration that’s the dominant problem, spending money on room treatment may not correctly resolve the issue. Room acoustics problems can be grouped into the following categories. 1. Air mass problems: – Standing waves with sound pressure peaks and suck-outs (and associated velocity peaks) – Velocity generated intermodulation 2. Reflection problems – Unwanted reflected signals at the listening position – Raised reverberant background noise floor The behavior of a room’s air mass is the most important consideration with room treatment. A significant air mass problem is a fundamental destroyer of performance - uncontrolled room modes produce associated velocity intermodulation, which damages every aspect of musical reproduction. -
Acoustics 101 for Architects a Presentation of Acoustical Terminology and Concepts Relating Directly to the Design and Construction of an Architectural Space
Acoustics 101 for Architects A presentation of acoustical terminology and concepts relating directly to the design and construction of an architectural space. Low-tech descriptions, explanations, and examples. By: Michael Fay This essay is tailored to the one group of people who have more influence over a building's acoustics than any other; architects. The focus is on Architectural Acoustics, a field that is broader than most imagine. To do justice to the theme, we must briefly touch on many subordinate topics, most having a synergetic relationship bonding architecture and sound. This paper is based on fundamentals, not perfection. It covers most of the basics, and explores many modern and esoteric matters as well. You will be introduced to interesting and analytical subjects; some you may know, some you may never have considered. Here are a few examples of what you'll find by reading on: . What is sound and why is it so hard to manage or control? . The length of low- and high-frequency sound waves vary by as much as 400:1. Why does this disparity matter? . How and why do various audible frequencies behave differently when interacting with various materials, structures, shapes and finishes? . There are three acoustical tools available to both the architect and the acoustician. What are they? How can they benefit or hinder the work of each craft? . Room geometry: Why some shapes are much better than others. Examples and explanations. Reverberation and echo: How do they differ? Which is better, or worse, and why? How much is too much, or too little? . -
Historical Introduction
HISTORICAL INTRODUCTION The arts of music, drama, and public discourse have both influenced and been influenced by the acoustics and architecture of their presentation environments. It is theorized that African music and dance evolved a highly complex rhythmic character due, in part, to its being performed outdoors-rather than the melodic line of early European music. Wallace Clement Sabine (1868–1919), an early pioneer in architectural acoustics, felt that the development of a tonal scale in Europe rather than in Africa could be ascribed to the differences in living environment. In Europe, prehistoric tribes sought shelter in caves and later constructed increasingly large and reverberant temples and churches. Gregorian chant grew out of the acoustical characteristics of the gothic cathedrals, and subsequently Baroque music was written to accommodate the churches of the time. In the latter half of the twentieth century both theater design and performing arts became technology driven, particularly with the invention of the electronic systems that made the film and television industries possible. With the development of computer programs capable of creating the look and sound of any environment, a work of art can now not only influence, but also define the space it occupies. 1.1 GREEK AND ROMAN PERIOD (650 bc - AD 400) Early Cultures The origin of music, beginning with some primeval song around an ancient campfire, is impossible to date. There is evidence (Sandars, 1968) to suggest that instruments existed as early as 13,000 bc. The understanding of music and consonance dates back at least to 3000 bc, when the Chinese philosopher Fohi wrote two monographs on the subject (Skudrzyk, 1954).