Assessing the Effects of Noise on Sound Identities of Historical Landmarks

The Sound of a Circular City: Towards a Circularity-Driven Quietness

The circular economy paradigm can be beneficial for urban sustainability by eliminating waste and pollution, by circulating products and materials and by regenerating nature. Furthermore, under an urban circular development scheme, environmental noise can be designed out. The current noise control policies and actions, undertaken at a source-medium-receiver level, present a linearity with minimum sustainability co-benefits. A circular approach in noise control strategies and in soundscape design could offer numerous ecologically related co-benefits. The global literature documenting the advantages of the implementation of circular economy in cities has highlighted noise mitigation as a given benefit. Research involving circular economy actions such as urban green infrastructure, green walls, sustainable mobility systems and electro-mobility has acknowledged reduced noise levels as a major circularity outcome. In this research paper, we highlight the necessity of a circularity and bioeconomy approach in noise control. To this end, a preliminary experimental noise modeling study was conducted to showcase the acoustic benefits of green walls and electric vehicles in a medium-sized urban area of a Mediterranean island. The results indicate a noise level reduction at 4 dB(A) when simulating the introduction of urban circular development actions.

Approaching Quietness as an Urban Sustainability Opportunity

Quietness in an urban environment is vital for the well-being of city residents. Nevertheless, the ambiguity in the conceptualization of the terms noise and quietness as urban acoustic planning and design objectives, has resulted in two different approaches: the soundscape approach and the noise control approach. The main purpose of this research is to supplement the existing approaches by proposing a new ecological acoustics approach in order to identify quiet areas in the city of Mytilene (Lesbos Island, North Aegean, Greece). The use of the soundscape approach involved the participation of Mytilene’s residents and the collection of subjective and objective eligibility criteria. By means of Multi-Criteria Decision Making two urban green areas were highlighted as potential quiet areas. For the noise control approach, road noise maps have been created through a commercial noise mapping software, validated by trough measurements. As a result, two areas located in the outskirts of the city were highlighted. Finally, the novel ecological acoustics approach involved acoustic recordings and the extraction of the Composite Urban Quietness Index (CUQI). The outcome of this approach converged with the soundscape approach results. Quietness, as an urban acoustic planning and design goal, could be viewed as an opportunity for ecologically sustainable urban environments.

Exploring the Effects of “Smart City” in the Inner-City Fabric of the Mediterranean Metropolis: Towards a Bio-Cultural Sonic Diversity?

“Smart city”, driven by digital technology is not only a technological but also a social, cultural and political project. A socially and culturally significant new urban ideal is born. This research paper is based on the narrative that the city appears as a palimpsest of interventions of all natures. History and shared memory, composition and superimposition, coherence and divergence are fundamental for its evolution. It is thus evident that ”Smart city” as a rather new urban ideal, but also as a disruptive innovation process, cannot be conceived nor implemented all at once; it must follow analogous processes of buildup and stratification. On the other hand, sounds are part of cities, of their sensory landscape, of their identity. They are one of the urban markers, along with the visual landscape. In this context, the paper focuses on the sound identity of the inner-city areas of the Mediterranean metropolis, posing the following research question: What are the transformations that “Smart city” can cause to the sound identity of a city? In dense urban fabric with high-rise buildings, high rates of exploitation, frequent transgressions of the legal construction and least free space in private plots, what can be the prospects of using “smart transport”, for enriching the city with positive soundscapes, thus improving its environmental quality? Following the metaphor of urban and acoustic palimpsest, we examine narratives of replacement of conventional cars with autonomous vehicles (AVs) and of private cars with car-pooling systems. The article concludes that spatialized intelligence can substantially and positively transform the sound identity of the Mediterranean metropolis and be the spearhead for an increase in bio-cultural sonic diversity. At least during the era when the city still appears as a palimpsest of interpositions, evoking the historic time.

Revisiting the Concept of Quietness in the Urban Environment-Towards Ecosystems' Health and Human Well-Being

There is plenty of proof that environmental noise is a major pollutant in the urban environment. Several approaches were successfully applied for its calculation, visualization, prediction and mitigation. The goal of all strategy plans regards its reduction and the creation of quietness. This study aims to revisit the concept of quietness in the urban environment and attempts to portray a new understanding of the specific phenomena. "Quietness" as a term retains an ambiguity, and so far, it can be described as the lack of something, meaning the lack of noise that is portrayed by means of intensity. Several studies describe quietness as the combination of perceptual soundscape elements and contextual factors that can be quantified, combined, weighed and used as indicators of healthy soundscapes. In this research, the focus is on setting aside all indicators, either measuring the intensity or contextual ones and use solely quantifiable metrics regarding the acoustic environment, thus introducing a new composite index called the composite urban quietness index (CUQI). After testing the CUQI, in order to verify the results of previous research regarding the identification of quiet Areas in the city of Mytilene (Lesbos Island, Greece), the study concludes that CUQI is efficiently functioning even in this early stage of development.