Preface

Several research works on noise and noise control are currently available for the scientific, technical, and general public. **Figure 1** shows a graph of published papers on noise control from 2001 to 2021. As shown, the number of publications increased from about 3000 to about 9000 in the last 20 years. Is it necessary to publish more? Our answer is yes. We believe there will always be a need for more publications on this topic because noise control is constantly evolving along with human activities, technologies, and environments. The more these things change, the more noise will be present and need to be controlled.

#### **Figure 1.**

*Publication trends retrieved from Scopus for the years 2001 – 2021 using the keywords "noise control".*

This book discusses different topics related to noise control, including noise control methods and techniques, noise pollution and solutions, and noise mapping.

> **Marco Caniato** Free University of Bolzano, Bolzano, Italy

> > **Federica Bettarello** University of Trieste, Trieste, Italy

**1**

and safety.

control" one.

**2. Noise control in literature**

given by literature papers:

1.noise related to electronic devices

**Chapter 1**

Controlled?

**1. Introduction**

minds and our thoughts.

*Marco Caniato and Federica Bettarello*

Introductory Chapter: Is Noise

Really Important? Should It Be

Is noise really important? This is a very challenging scientific question. There are several literature works dealing with noise and its control. Anyway, why this physic

In years, researchers all over the word explored the entire acoustics field. If one writes "noise" on Google Scholar, almost 6 million results appear. This means that this parameter, this presence in our lives is of paramount interest and clearly occupies our

Everybody knows that sound is a wave propagation in a dense mean. However, this is the academic definition. Aside of it, the perception is what makes the difference. And clearly what changes between *sound* and *noise*. The physics is the same, but sound is something positive such as music one likes or the voice of a beloved person. Noise is

For these reasons, perception is what drives the research, rather than the physic phenomenon per se. Human perception varies from individual to individual. It is rather different, but some common trends are possible to find in literature. Thus, in the noise history, standards, scientific proposals, and law requirements were published, discussed, and imposed with the sole aim to control noise emission.

From what above reported, it is clear that the control of noise is needed for human purposes, for comfort reasons, and finally (and more importantly), for health issues

Literature is full of excellent works related to noise control. When one looks more in depth, some useful pieces of information can be derived. In order to do so, it is useful to picture the connection between the several different topics related to the "noise

When referring to **Figure 1**, it is possible to see that seven principal areas are related to the keyword "noise control," namely (in order of numerical importance

phenomenon is so important for humans and specifically for scientists?

something disturbing such as industrial noise and traffic noise.
