Multi-Sensor Device for Traceable Monitoring of Indoor Environmental Quality.

The Indoor Environmental Quality (IEQ) combines thermal, visual, acoustic, and air-quality conditions in indoor environments and affects occupants' health, well-being, and comfort. Performing continuous monitoring to assess IEQ is increasingly proving to be important, also due to the large amount of time that people spend in closed spaces. In the present study, the design, development, and metrological characterization of a low-cost multi-sensor device is presented.

Use of Metamaterials to Reduce Acoustic Noise Emissions from Lower Limb Prostheses: An Experimental Validation.

Recent human-centred design studies suggest that acoustic noise could affect the physical use and psychological acceptance of a biomedical device. These aspects are especially relevant in the prosthetic field, in which device loudness is often related to rejection. The aim of the study is to inquire on the possibility to reduce the acoustic noise emitted by a robotic leg prosthesis by improving its casing.

Effects of Face Masks on Physiological Parameters and Voice Production during Cycling Activity.

This study investigates the effects of face masks on physiological and voice parameters, focusing on cyclists that perform incremental sports activity. Three healthy male subjects were monitored in a climatic chamber wearing three types of masks with different acoustic properties, breathing resistance, and air filtration performance. Masks A and B were surgical masks made of hydrophobic fabric and three layers of non-woven fabric of 100% polypropylene, respectively.

Investigation on the diffusive surface modeling detail in geometrical acoustics based simulations.

This study shows an investigation on the modeling level of detail of diffusive surfaces, which strongly influences the efficiency of geometrical acoustic based software. One diffusive condition of the lateral wall of a shoebox hall has been modeled as (a) flat surfaces with surface scattering coefficient and (b) three-dimensional relief including edge diffraction. The analysis has been performed by comparing the conventional acoustic parameters, which showed no significant differences, and by subjectively investigating the sensitivity of listeners to both modeling approaches, which highlighted that perceptual differences related to reverberance and spaciousness are clearer when using the modeling approach (b).

A Cross-Sectional Survey on the Impact of Irrelevant Speech Noise on Annoyance, Mental Health and Well-being, Performance and Occupants' Behavior in Shared and Open-Plan Offices.

This cross-sectional survey has compared subjective outcomes obtained from workers in shared (2⁻5 occupants) and open-plan (+5 occupants) offices, related to irrelevant speech, which is the noise that is generated from conversations between colleagues, telephone calls and laughter. Answers from 1078 subjects (55% in shared offices and 45% in open-plan offices) have shown that irrelevant speech increases noise annoyance, decreases work performance, and increases symptoms related to mental health and well-being more in open-plan than in shared offices. Workers often use headphones with music to contrast irrelevant speech in open-plan offices, while they take a break, change their working space, close the door or work from home in shared offices.

Objective and perceptual evaluation of distance-dependent scattered sound effects in a small variable-acoustics hall.

Performance spaces are characterized by a complex sound field, due to the presence of absorptive and diffusive surfaces. In situ evaluations of the acoustic effects that these surfaces have on the objective acoustic parameters and on sound perception have not yet been fully understood. To this aim, acoustic measurements have been performed in a variable-acoustic concert hall, the Espace de Projection, at the Institut de Recherche et Coordination Acoustique/Musique.

Objective and perceptual assessment of the scattered sound field in a simulated concert hall.

Acoustic scattering audibility thresholds are needed for the efficient design of performance spaces and to increase the accuracy of geometric room acoustic models. This paper focuses on the evaluation of the perceptual thresholds of the scattering coefficient through listening tests in simulated concert halls. It also deals with an investigation on the sensitivity of room acoustic parameters to scattering coefficients.