Listen to Your City, Both in Its Strengths and Weaknesses

“To listen to the noise of a city is to hear a living city. To hear its moments of strength and weakness.”

In technical terms, resilience is the ability of materials to withstand shock. A city is made up of both material things and living beings – humans, animals, and plants – that together form a fragile ecosystem that the slightest shock can disturb. Therefore resilience also indicates the ability of individuals, communities, and related ecosystems to bounce back and make a fresh start after a physical shock and stressors.

Urban resilience comprises a “city’s capacity to prepare for, respond to, and adapt to dangerous and disruptive events” according to José Angel Gurria in his article also featured in this series, and the “capacity to bounce back” as underlined by Dr. Oswar Muadzin Mungkasa. It speaks to the capacity of individuals, communities, systems, institutions, and businesses to anticipate and to resist. It also includes proactive preparedness.

Securaxis is proud to partner with NewCities and sponsor this edition of The Big Picture on Resilient Cities. A high-level panel of experts has answered our call for which we are grateful. Each author has written about the resilience of cities based on their experience and profession, offering us a broad perspective on this theme and much food for thought.

Sensors of all kinds (for example, temperature, air pressure, and pollution) are installed in cities today to help build resilience. However, a principal characteristic of a city is its noise and one human sense that is not yet exploited to its true value is the ability to listen.

As the Chief Operations Officer of Securaxis, I would like you to listen to your city. It is sometimes easy to distinguish the different sounds that make up the everyday noise in your city. Vehicles move about. Ambulance sirens wail. Children yell at playtime. Workmen drill roads. These easily identifiable and characteristic noises change by time of day, weather, and season. Other unexpected and possibly dangerous things happen that generate – depending on where you are living – exceptional sound energy such as use of weapons, traffic accidents, failure in an infrastructure, screaming. Each of these also has its own particular sound, detectable or not, by the human ear. Whilst noise is measured in decibels, it can be perceived in a thousand different ways, depending on the human’s auditory acuity, the attention paid, the degree of sound isolation, and the source of the noise.

To listen to the noise of a city is to hear a living city; to hear its moments of strength and weakness. But we still need to be able to locate, identify, and analyze what we hear to understand it. Enter: smart acoustic monitoring. Integrating recent technological advancements in the fields of IoT (Internet of Things), artificial intelligence, and acoustic detection, Securaxis has developed the means to detect and monitor specific sounds in a specific place permitting accurate and reliable monitoring of the activities that generate them. In relation to a city’s resilience, the detector technology is backed by self-optimizing software (machine learning), making the system increasingly useful for any specific issue in a given urban environment.

Think, for instance, about critical government infrastructures such as airports, bridges, tunnels, and dams. Acoustic sensors placed on, and integrated into, these infrastructures can be used to monitor their integrity by capturing the sounds emitted when material failures occur. Acoustic sensors can detect and locate failures before an infrastructure breakdown (predictive maintenance). Smart Acoustic sensors allow for the counting and categorization of vehicles, as well as determining their direction.

Think also about how real-time and accurate detection would bring the possibility of more rapid and targeted emergency response. Multifunction sensors would be capable of detecting and analyzing all types of sounds associated with violence and insecurity such as explosions, shots, screams, and breaking glass. The major advantage of intelligent acoustic monitoring over video surveillance in any urban context – other than it being much cheaper – is that it does not carry the same implications for privacy of citizens.

Biodiversity is a key indicator of an ecosystem’s stability, a key factor in human health, and is a major necessity as part of “resilient cities.” Preserving it requires a better understanding of the complex relationships between species and their environments together with raised awareness of the ecological impact of human activities. It has been demonstrated that sound is an efficient indicator for monitoring ecosystem biodiversity. Wildlife acoustic monitoring can provide information such as species present, their health and condition of their habitat and, importantly, it can determine a species’ interaction with human habitat or human built infrastructure.

These are only a few examples of what can be done by monitoring sound. The progress of humankind has inevitably brought a major proportion of an increasingly growing population to live in urban environments. As a result, we are now even more dependent on our security, transport, and major structures; massive buildings such as bridges, airports, power generation. What is not yet apparent is the means for early detection of when these features of modern human existence are attacked or are about to fail. In parallel, measuring their impact on ecosystems is time consuming and expensive. “City planners need access to a variety of tools and technologies for their day-to-day decisions to become more efficient” Shruti Rao reminds us.

Securaxis provides the means to turn noise into data to inform action. This sits at the heart of assessing, preparing, and ensuring a city’s resilience.