Massimiliano Masullo

The influence of visual characteristics of barriers on railway noise perception.

Noise annoyance is considered as the main effect of noise, it is a complex and multifaceted psychological concept dealing with immediate behavioral and evaluative aspects. In the last decades the research has intensely investigated the correlation between noise exposure and noise annoyance, nevertheless recent studies confirm that non-auditory factors influence the noise perception of individuals. In particular audio-video interaction can play a fundamental role. Today Immersive Virtual Reality (IVR) systems allow building laboratory test providing realistic experiences of the surrounding environment to detect more accurate information about the reactions of the local population. Regarding the interventions for environmental noise control the barriers represent the main solution; however some aspects related to their visual characteristic have to be further investigated. This paper presented a case study, where a sample of residents living close to a railway line assessed noise-related aspects for several barriers with different visual characteristics in an IVR laboratory test. In particular, three main factors were analyzed: the barrier type concerning the visibility of the noise source through the screen, the visual aspect of the barrier concerning some aesthetic issues and the noise level at the receiver concerning the acoustic performance of the barrier and the magnitude of the sound source. The main results of the ANOVA analysis showed that for transparent barriers Perceived Loudness and Noise Annoyance were judged lower than for opaque barriers; this difference increased as noise level increased.

The Effects of Vision-Related Aspects on Noise Perception of Wind Turbines in Quiet Areas

Preserving the soundscape and geographic extension of quiet areas is a great challenge against the wide-spreading of environmental noise. The E.U. Environmental Noise Directive underlines the need to preserve quiet areas as a new aim for the management of noise in European countries. At the same time, due to their low population density, rural areas characterized by suitable wind are considered appropriate locations for installing wind farms. However, despite the fact that wind farms are represented as environmentally friendly projects, these plants are often viewed as visual and audible intruders, that spoil the landscape and generate noise. Even though the correlations are still unclear, it is obvious that visual impacts of wind farms could increase due to their size and coherence with respect to the rural/quiet environment. In this paper, by using the Immersive Virtual Reality technique, some visual and acoustical aspects of the impact of a wind farm on a sample of subjects were assessed and analyzed. The subjects were immersed in a virtual scenario that represented a situation of a typical rural outdoor scenario that they experienced at different distances from the wind turbines. The influence of the number and the colour of wind turbines on global, visual and auditory judgment were investigated. The main results showed that, regarding the number of wind turbines, the visual component has a weak effect on individual reactions, while the colour influences both visual and auditory individual reactions, although in a different way.

The Large Theatre of Pompeii: Acoustic Evolution

This paper reports the acoustic evolution of the “Large Theatre” of Pompeii: during the Greek-Hellenistic and Roman period, and through to the present time. Initially the style of the theatre was Greek-Hellenistic with an elongated U shape and a cavea built into the top of a hill. During the Roman period the theatre shape was changed with a larger scene and a summa cavea added to accommodate about 5.000 spectators. After being recovered from under the Vesuvius lava it was partially reconstructed. Most recently the original grass-covered cavea has been paved with bricks and today the theatre provides a venue for a variety of types of performance. Its acoustic characteristics have been analysed using a virtual model for the Greek- Hellenistic and Roman period, and then, for the later configurations, when the cavea was grass-covered and then paved with bricks, with acoustic measurements.

The effect of vision on the perception of the noise produced by a chiller in a common living environment

Over the years, different noise sources related to community noise and their potential for eliciting noise annoyance have been investigated. Despite being a very common source within the urban realm, there is a current lack of literature on the perception of noise produced by small-medium sized sources like chillers and air conditioning devices. There are relatively few studies on the influence of audiovisual factors on noise perception for such sources. The main aim of this paper was to investigate the influence of the visibility of a chiller on perceived loudness and self-reported annoyance in a common indoor environment. Furthermore, this research aimed to investigate whether the abovementioned effects persisted in the presence of a cognitive task. To this purpose, two laboratory experiments were performed by means of an immersive virtual reality (IVR) system. Results show that the distance of the chiller influenced the noise perception, while the visibility of the chiller itself does not, assuming that a visual reference context is provided. Regarding the cognitive task, it was found to reduce the mean individual ratings of both the perceived loudness and noise annoyance related to the chiller, signifying that for the investigated sound source characterized by small spectral and temporal variation, it might have inhibited the attentional listening. These findings suggest that there is room for the implementation of recommendations for the design and management of such sources in the increasingly dense built environment.

Noise exposure in school gymnasia and swimming pools

School gymnasia and swimming pools are generally environments affected by poor acoustic conditions due to absence of sound absorbing materials, noisy sport activities, presence of many students at the same time and intensive use of blowing whistles to enforce the communication. The consequence is that physical education teachers can not only show long term stress but they can also be exposed to noise risk to noise-induced hearing loss. Investigation has shown that the problem is quite large; as many as 20�25% of physical education teachers can be affected by a noise exposure higher than acceptable limits. It is then necessary to analyze in detail all factors that can influence the noise in these special school environments in order to develop simple acoustical guidelines useful for school officials for stress management and hearing conservation programs.

Auditory recognition of familiar and unfamiliar subjects with wind turbine noise.

Considering the wide growth of the wind turbine market over the last decade as well as their increasing power size, more and more potential conflicts have arisen in society due to the noise radiated by these plants. Our goal was to determine whether the annoyance caused by wind farms is related to aspects other than noise. To accomplish this, an auditory experiment on the recognition of wind turbine noise was conducted to people with long experience of wind turbine noise exposure and to people with no previous experience to this type of noise source. Our findings demonstrated that the trend of the auditory recognition is the same for the two examined groups, as far as the increase of the distance and the decrease of the values of sound equivalent levels and loudness are concerned. Significant differences between the two groups were observed as the distance increases. People with wind turbine noise experience showed a higher tendency to report false alarms than people without experience.

Preliminary studies on the relation between the audio-visual cues' perception and the approaching speed of electric vehicles

For decades, quiet and zero emission vehicles have been considered the challenge for researchers and for the industry. Today, despite the great results obtained in the fields of air and noise pollution, the electric vehicles (EV) and hybrid electric vehicles (HEV) have raise an important question regarding the pedestrian safety. At the speeds permitted in urban areas (<50 km/h) these vehicles are considerably quieter than the traditional ones powered by gasoline or diesel. Nevertheless the amount of auditory cues associated to the approaching of these vehicles can be reduced. This can determine an increase of the risk of accidents for the pedestrians. Even though the recent studies on this problem are focused, mainly, on the minimum sound levels and on the spectral content of the approaching vehicles, further aspects of the semantic contents change of the event should be considered. In this paper a preliminary investigation on the relationship, and possible incoherence, among the approaching speed of the...

Soundscape in the old town of Naples: Signs of cultural identity

Like all cities in Magna Grecia, the ancient Neapolis was built along three main parallel, tight, and straight streets called decumani. Since then and during the following centuries, commercial and handicraft activities, as well as social life, have been developed along these streets. The narrow ground rooms forced shopkeepers to occupy the main street to show their merchandise using vocal appeals to magnify their product, and handicrafts to work directly on the street (hammering, sawing, etc.). Music artists had their performance on the streets too. The soundscape in the area was a strong symbol of the Neapolitan cultural identity. Nowadays decumani have kept the main features of the past but some of these are overrun by road traffic. To investigate in which way the traffic noise has modified the soundscape perception and cultural identity, sound walks were registered during day and night time. A number of residents were interviewed and laboratory listening tests were carried out. Despite the congested u...

The Speech Intelligibility Aboard Metros in Different Running Conditions

Luigi Maffei1), Massimiliano Masullo1), Natalia Alexeeva1), Umberto Palmieri1), Vincenzo Paolo Senese2) 1) Built Environment Control Laboratory R.I.A.S., Second University of Naples, via San Lorenzo 81031, Aversa (CE), Italy. luigi.maffei@unina2.it 2) Department of Psychology, Laboratory of Cognitive Science and Immersive Virtual Reality, Second University of Naples, via Vivaldi 81100, Caserta, Italy

On the perception of Limited Traffic Zones asurban noise mitigation action

Abstract Environmental noise is a very important issue in modern urban agglomerations and new policies are being explored in order to reduce high sound-pressure levels from transportation and industry, especially in urban contexts. Considering this issue from the subjective perspective, environmental noise is often related to noise annoyance. Over the years, possible solutions were explored for urban sound planning beyond the mere noise control engineering techniques and a number of international projects proposed innovative approaches to deal with this issue: most of them were traffic-related. In order to support the city management, it is suitable to analyse possible indirect effects of traffic limitations on the perception of the sonic environment. Indeed, it was observed that even traffic management plans with no specific focus on noise mitigation are likely to have acoustic implications. The present study investigated the variations of the sonic environment induced by the implementation of a Limited Traffic Zone (LTZ) in the historic centre of Naples, in terms of objective parameters and perceived quality of the ‘sound’ component by means of noise and social surveys before, immediately after and one year after the LTZ implementation, in order to check for possible time effects. Results show that the sample interviewed immediately after the LTZ implementation reported overall positive opinions on the sonic environment and its variation, while the sample interviewed one year after tended to shift to more neutral opinions. This finding suggests that the LTZ could be considered an effective environmental strategy for the urban noise control, but it should be adequately actuated in order to preserve the achievements in terms of noise reduction and subjective perception by the local population.