The Impact of Thin Asphalt Layers as a Road Traffic Noise Intervention in an Urban Environment

Low-noise thin asphalt layers (TALs) are a feasible solution to mitigate road traffic noise in urban environments. Nevertheless, the impacts of this type of noise intervention are reported mostly regarding noise levels, while non-acoustic aspects influencing the population perception are still little-known. This study investigates the implementation of TALs in two streets of Antwerp, Belgium. The effectiveness of the intervention was measured via noise modelling and acoustic measurements of road traffic noise. A reduction of 2.8 dB in noise exposure was observed in Lden and Lnight, while SPB measurements showed decreases up to 5.2 dB on the roadside. The subjective impacts of the TALs were evaluated via self-administered surveys and compared to results from control streets. The annoyance indicators were positively impacted by the TALs implementation, resulting in annoyance levels similar or lower than in the control streets. The TALs did not impact the reported physical complaints, sleep quality, and comfort level to perform activities.

Do Flexible Silicone Tubes Immersed in Water Combined With Vocalise Improve the Immediate Effect on Voice?

Purpose: This study aimed to analyze the immediate effect on a singer's voice of a flexible silicone tube immersed in water combined with ascending and descending vocalise scales compared with ascending and descending vocalise scales alone. Method: A pre- and post-intervention quasi-experimental study was conducted. Thirty adult singers between 18 and 45 years old with no laryngeal disorders performed the two techniques for 3 min each on different days. Acoustic measurements of frequency, jitter, shimmer, glottal-to-noise excitation ratio, noise, smoothed cepstral peak prominence (CPPS), maximum phonation time (MPT), voice range profile, and self-perceived vocal effort (Borg Category Ratio 10-BR Scale adapted for vocal effort) were assessed before and after performing the techniques. Results: The results indicated an increase in singers' CPPS and MPT values and a decrease in shimmer and noise when performing with a flexible silicone tube immersed in water combined with vocalise. The singers reported a perception of decreased vocal effort after both methods. However, the diminished perceived vocal effort became more pronounced with the tube phonation technique combined with vocalise. Conclusions: Phonation in tubes combined with vocalise improved the vocal acoustic parameters (including cepstral measurements), increased MPT, and diminished perceived vocal effort. Although using vocalise alone diminished perceived vocal effort, this decrease was more pronounced in the tube phonation technique combined with vocalise.