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The Psychophysics of Human Sound Localization


The field of spatial hearing has exploded in the decade or so since Jens Blauert's classic work on acoustics was first published in English. This revised edition adds a new chapter that describes developments in such areas as auditory virtual reality (an important field of application that is based mainly on the physics of spatial hearing), binaural technology (modeling speech enhancement by binaural hearing), and spatial sound-field mapping. The chapter also includes recent research on the precedence effect that provides clear experimental evidence that cognition plays a significant role in spatial hearing.

The remaining four chapters in this comprehensive reference cover auditory research procedures and psychometric methods, spatial hearing with one sound source, spatial hearing with multiple sound sources and in enclosed spaces, and progress and trends from 1972 (the first German edition) to 1983 (the first English edition)—work that includes research on the physics of the external ear, and the application of signal processing theory to modeling the spatial hearing process. There is an extensive bibliography of more than 900 items.


Charles Stevens, a prominent neurobiologist who originally trained as a biophysicist (with George Uhlenbeck and Mark Kac), wrote this book almost by accident. Each summer he found himself reviewing key areas of physics that he had once known and understood well, for use in his present biological research. Since there was no book, he created his own set of notes, which formed the basis for this brief, clear, and self-contained summary of the basic theoretical structures of classical mechanics, electricity and magnetism, quantum mechanics, statistical physics, special relativity, and quantum field theory.

The Six Core Theories of Modern Physics can be used by advanced undergraduates or beginning graduate students as a supplement to the standard texts or for an uncluttered, succinct review of the key areas. Professionals in such quantitative sciences as chemistry, engineering, computer science, applied mathematics, and biophysics who need to brush up on the essentials of a particular area will find most of the required background material, including the mathematics.



How does it happen that billions of stars can cooperate to produce the beautiful spirals that characterize so many galaxies, including ours? This book presents a theory of spiral structure that has been developed over the past three decades under the continuous stimulus of new observational studies. The theory unfolds in a way that can be grasped by any reader with an undergraduate science background who is interested in astronomy, as well as by graduate students and scientists actively involved in astronomy or related subjects who want to see the "backbone" and the physical content of the theory.

The foundations of this theoretical framework were laid in the early 1960s, following the pioneering work of B. Lindblad. C. C. Lin had already contributed significantly to the field of fluid mechanics when he turned his attention to spiral structures, and he has focused on the problem ever since. Giuseppe Bertin joined this research effort when he first visited at MIT in 1975, bringing to the project knowledge from his work on elliptical galaxies and plasma astrophysics. Together, Bertin and Lin have contributed to the exciting developments on spiral structure of the last few decades, working closely with many observers and other theorists. In this book they describe the density-wave theory with the goal of making the key concepts and astrophysical implications explicit and accessible.

The essence of the solution Bertin and Lin present is that the spirals are wave rather than material phenomena and generally trace intrinsic characteristics of the individual galaxies. The book is in three parts —Physical Concepts, Observational Studies, and Dynamical Mechanisms—with most of the technical details confinedto the last part.

Research and Perspectives
Edited by BC Crandall and James Lewis

Advances in physics, molecular biology, and computer science are converging on the capacity to control, with molecular precision, the structure and function of matter. These twenty original contributions provide the first broad-based multidisciplinary definition and examination of the revolutionary new discipline of molecular engineering, or nanotechnology. They address both the promise as well as the economic, environmental, and cultural challenges of this emerging atomic-scale technology.

Leaders in their field describe current technologies that feed into nanotechnology - atomic imaging and positioning, protein engineering, and the de novo, design and synthesis of self-assembling molecular structures. They present development strategies for coordinating recent work in chemistry, biotechnology, and scanning-probe microscopy in order to successfully design and engineer molecular systems. They also explore advances in molecular and quantum electronics as well as reversible computational systems and the fundamental physical constraints on computation. Additional chapters discuss research efforts in Japan and present the prospects of nanotechnology as seen from the perspective of a microtechnologist.

The final section looks at the implications of success, including the prospects of enormous computational power and the radical consequences of molecular mechanical systems in the fields of medicine and life extension.

BC Crandall is Cofounder and Vice President of Prime Arithmetics, Inc.

Contributors: Robert Birge. Federico Capasso. BC Crandall. K. Eric Drexler. Gregory Fahy. Richard Feynman. John Foster. Tracy Handel. Bill Joy. Arthur Kantrowitz. Joseph Mallon. Norman Margolus. Ralph Merkle. Lester Milbrath. Gordon Tullock. Hiroyuki Sasabe. Michael Ward.

The Life of Jerrold R. Zacharias - Scientist, Engineer, Educator

Jerrold Zacharias (1905-1986) was a physicist well placed by historical circumstance to take a central part in the development of American science, science policy, and science education. In a clear, nontechnical account, Jack Goldstein tells the story of this entrepreneurial American scientist who played an essential part in experiments important to the development of quantum mechanics, who later became an advisor to the government during much of the Cold War period, and whose leadership in educational reform resulted in the restructuring of the entire American high school science curriculum.Zacharias lived at a time when an individual with imagination and courage could make a difference, whether at the forefront of science or in matters of public policy. He believed that every citizen, even those with modest scientific sophistication and knowledge, could learn to think like a scientist. Now, at a time when the issues of science education and science literacy are again of compelling national interest, his ideas merit close attention.Goldstein describes Zacharias's coming of scientific age in the early 1930s, as a member of 1. 1. Rabi's group at Columbia, and examines the leading role he played during World War II at MIT's Radiation Laboratory and at the Manhattan Project. From about 1955 on, Goldstein observes, Zacharias made significant contributions to science education in physics, chemistry, biology, and mathematics at the primary, secondary, and college levels. As a result of his initiatives, science and mathematics curriculum development flourished in a number of third-world countries.Jack S. Goldstein is Professor of Physics at Brandeis University.

These 28 contributions by leading researchers - from such diverse disciplines as chemistry, biology, physics, mathematics, and physiology - describe recent experiments, numerical simulations, and theoretical analyses of the formation of spatial patterns in chemical and biological systems.

Chemical patterns have been systematically studied since the field was established by Alan Turing's landmark 1952 paper, "The chemical basis for morphogenesis," yet only recently have new experimental techniques and numerical analyses of reaction-diffusion equations opened the way to understanding stationary and traveling wave patterns.

This collection summarizes the exciting developments in this rapidly growing field. It shows that some biological patterns have been found to be strikingly similar to patterns found in simple, well-controlled laboratory chemical systems, that new chemical reactor designs make it possible to sustain chemical patterns and to study transitions between different kinds of patterns, and that nearly 40 years after Turing's paper, the patterns predicted by Turing have finally been observed in laboratory experiments.

Harry L. Swinney is Sid Richardson Foundation Regents Chair, Department of Physics, and Director of the Center for Nonlinear Dynamics at the University of Texas at Austin. Valentin I. Krinsky is Head of the Autowave Laboratory, Institute of Biological Physics, Academy of Sciences, Pushchino, USSR.

Chapters cover: Spiral, Ring, and Scroll Patterns: Experiments. Spiral, Ring, and Scroll Patterns: Theory and Simulations. Fronts and Turing Patterns. Waves and Patterns in Biological Systems.

Theory, Application, and Hardware

Lattice gas methods are new parallel, high-resolution, high-efficiency techniques for solving partial differential equations. This volume focuses on progress in applying the lattice gas approach to partial differential equations that arise in simulating the flow of fluids. It introduces the lattice Boltzmann equation, a new direction in lattice gas research that considerably reduces fluctuations.

The twenty-seven contributions explore the many available software options exploiting the fact that lattice gas methods are completely parallel, which produces significant gains in speed. Following an overview of work done in the past five years and a discussion of frontiers, the chapters describe viscosity modeling and hydrodynamic mode analyses, multiphase flows and porous media, reactions and diffusion, basic relations and long-time correlations, the lattice Boltzmann equation, computer hardware, and lattice gas applications.

Sound, Structures, and Their Interaction covers theoretical acoustics, structural vibrations, and the interaction of elastic structures with an ambient acoustic medium. It is intended both as a text for graduate-level courses and as a reference book for researchers in various areas of underwater acoustics. It is self-contained and presents the theoretical foundations in sound radiation and scattering and in plate and shell vibrations required for the solution of coupled acoustics-structural vibrations problems.

First published in 1972, Sound, Structures, and Their Interaction has been extensively revised to incorporate new results, with a particular emphasis on novel asymptotic solutions that provide physical insight as well as a check on numerical solutions. The book differs from other texts not only in its thorough treatment of the interaction of elastic structures with the ambient medium but also in its derivation of short-wavelength asymptotic solutions of sound diffraction (creeping waves) and of high-frequency vibrations of shells.

This new edition also covers specialized problems, such as sound propagation in bubble swarms and in liquid-filled elastic waveguides and the effect of stiffeners on the response of submerged plates. The chapters dealing with acoustics proper provide powerful analytical techniques that the reader can apply to specific radiation and scattering situations.

Miguel C. Junger is President and Principal Scientist, Cambridge Acoustical Associates, Inc. David Feit is a Research Scientist in the Ship Acoustics Department of the David W. Taylor Naval Ship Research and Development Center, Bethesda, Maryland.

This major work covers almost all that has been learned about the acoustics of stringed instruments from Helmholtz's 19th-century theoretical elaborations to recent electroacoustic and holographic measurements.

Many of the results presented here were uncovered by the author himself (and by his associates and students) over a 20-year period of research on the physics of instruments in the violin family. Lothar Cremer is one of the world's most respected authorities on architectural acoustics and, not incidentally, an avid avocational violinist and violist.

The book—which was published in German in 1981—first of all meets the rigorous technical standards of specialists in musical acoustics. But it also serves the needs and interests of two broader groups: makers and players of stringed instruments are expressly addressed, since the implications of the mathematical formulations are fully outlined and explained; and acousticians in general will find that the work represents a textbook illustration of the application of fundamental principles and up-to-date techniques to a specific problem.

The first—and longest—of the book's three parts investigates the oscillatory responses of bowed (and plucked) strings. The natural nonlinearities that derive from considerations of string torsion and bending stiffness are deftly handled and concisely modeled.

The second part deals with the body of the instrument. Special attention is given to the bridge, which transmits the oscillations of the strings to the wooden body and its air cavity. In this case, linear modeling proves serviceable for the most part—a simplification that would not be possible with lute—like instruments such as the guitar.

The radiation of sound from the body into the listener's space, which is treated as an extension of the instrument itself, is the subject of the book's final part.

Analysis and Synthesis

Random variation over space and time is one of the few attributes that might safely be predicted as characterizing almost any given complex system. Random fields or "distributed disorder systems" confront astronomers, physicists, geologists, meteorologists, biologists, and other natural scientists. They appear in the artifacts developed by electrical, mechanical, civil, and other engineers. They even underlie the processes of social and economic change. The purpose of this book is to bring together existing and new methodologies of random field theory and indicate how they can be applied to these diverse areas where a "deterministic treatment is inefficient and conventional statistics insufficient." Many new results and methods are included.

After outlining the extent and characteristics of the random field approach, the book reviews the classical theory of multidimensional random processes and introduces basic probability concepts and methods in the random field context. It next gives a concise amount of the second-order analysis of homogeneous random fields, in both the space-time domain and the wave number-frequency domain. This is followed by a chapter on spectral moments and related measures of disorder and on level excursions and extremes of Gaussian and related random fields.

After developing a new framework of analysis based on local averages of one-, two-, and n-dimensional processes, the book concludes with a chapter discussing ramifications in the important areas of estimation, prediction, and control. The mathematical prerequisite has been held to basic college-level calculus.

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