Bøger af Sanichiro Yoshida

Most physical phenomena exhibit spatiotemporal features interpreted as wave dynamics. Various diagnostic technologies use some waves such as light, sound, and microwaves. A proper understanding of wave dynamics is essential to interpret these physical phenomena and apply the technology efficiently. However, the physics underlying the wave-like behavior of real-world systems is not necessarily straightforward. Often the mathematical description of these physics is hard to understand. Consequently, the interpretation of diagnostic signals is not simple, which sometimes leads to an incorrect diagnosis. This book aims to solve these problems by describing the related topics on a sound physical basis and explaining them intuitively for easy digestion. Presents real-world examples of oscillatory and wave systems to help the reader understand wave dynamics while explaining numerical methods. Explains the physics and mathematics underlying wave dynamics in intuitive fashions.

This book discusses acoustic waves in five chapters. Chapter 1 reviews the general properties of waves. Chapter 2 presents the acoustic waves in fluid and solids, including the wave equations in the respective media. Chapter 3 discusses the propagation of audible acoustic waves in the air. The discussion includes analyses of speech and music we hear in the time and frequency domains. Chapter 4 discusses the propagation of acoustic waves in solids. Unlike in the air, sound waves take complicated forms in solids; they can be both in longitudinal and transverse modes, and mode conversions can occur upon reflection. Although these behaviors make the analysis difficult, we can apply them to engineering problems. Chapter 5 describes the transduction of acoustic signals. It presents acoustic transmitters and sensors along with their operation principles. Finally, Chapter 6 presents several techniques used in engineering. It is also useful to consider applying acoustic and optical techniques to engineering problems.

Waves are everywhere in our daily life. We all experience sound and light with our ears and eyes, we use microwaves to cook, and radio waves are transmitted from and are received by our cell phones. These are just some examples of waves that carry energy from point A to B. However, we may not know details of the physics underlying all these waves. It is important to understand the mechanisms that generate wave dynamics for a given system. It is not straightforward to explain how an electromagnetic ield becomes oscillatory and propagates as a wave. Waves sometimes represent the underlying dynamics of observed phenomena at a fundamental level of physics.This book is designed to explore these mechanisms by discussing various aspects of wave dynamics from as many perspectives as possible. The target audiences are undergraduate students majoring in engineering science and graduate students majoring in general engineering. Going beyond the typical approach to learning science, this book discusses wave dynamics and related concepts at various levels of mathematics and physics, sometimes touching on profound physics behind them. This book was written to help readers learn wave dynamics on a deep physical level, and develop innovative ideas in their own fields.