Koji Nagahata

Changes to soundscapes at outdoor gathering spaces in Fukushima, Japan, caused by the severe nuclear power plant accident

Five years have passed since the accident at the Fukushima Daiichi Nuclear Power Plant, which caused changes to daily life in the city of Fukushima, Japan. These daily life alterations caused changes to the soundscapes of Fukushima, which are still evolving now. In this study, the soundscape change at Fukushima’s outdoor gathering spaces is discussed using field recordings by the author. Shortly after the accident, few human voices could be heard at outdoor gathering spaces, but natural sounds such as birdsongs could be heard as usual per the time of year. Park decontamination started during summer 2011. In some parks where decontamination was successfully completed, people’s voices and sounds of children playing returned during spring 2012. However, in other parks where decontamination was done but ineffective, the lack of human voices and artificial sounds continued until radiation levels decreased sufficiently. In this way, soundscape change at outdoor gathering spaces represents people’s attitude towa...

A historical study of car horn noise in Japan from a soundscape viewpoint

This paper discusses the role of the public in solving noise problems, through a review of the history of the car horn noise problem in Japan. Noise problems caused by car horns began occurring around 1930, and subsequently recurred around 1950. In both cases, official regulations were enacted; however, these regulations were only temporarily effective. It was a civic movement, in which a variety of groups participated, that ultimately led to a permanent resolution of the issue. The most important factors for the success of this movement were believed to be the breadth of participation and the successful fulfillment of each groups role. History suggests that regulations alone are insufficient for resolving the issue of noise problem from vehicles, and public participation is crucial to achieve a solution and further improve the soundscape. Moreover, it appears that the role of the public in solving noise problems lies in their change of attitude toward, and active efforts to control, noise. Therefore, the most important point of discussion regarding social aspects of a noise policy must concern how to involve a large proportion of the public in the resolution of noise problems and further improving the soundscape.

The Adequate Sound Levels for Acoustic Signs for Visually Impaired in the Sound Environment with Ambient Musics from shops

Providing auditory signs for the visually impaired is one of the most effective ways to support their orientation and mobility. Although the use of such sounds by the visually impaired has been revealed qualitatively, the acoustical properties of ideal sound‐designs for them have not known sufficiently, even a basic property such as the sound level of these sounds. On the other hand, the advertising sounds from shops such as ambient musics are the one of the typical sounds in the Japanese downtown. These sounds also disturb their sound information listening and make their mobility difficult. Our previous studies revealed the adequate sound levels of acoustic signs under the road traffic noise environment. This study discusses the the effect of the ambient musics from shops on the adequate sound levels of acoustic signs through the psychoacoustical experiment. The results showed that the difference between the adequate sound level of acoustic signs and the environmental noise levels are larger than that under the road traffic noise environment. This trend is thought to be attributed to the frequency characteristics of the acoustical signs and the environmental noise.

Acoustic environmental problems at temporary shelters for victims of the Mid‐Niigata Earthquake

An earthquake on 23 October 2004 inflicted heavy damage on the Mid‐Niigata district. The earthquake isolated Yamakoshi village; consequently, all the village residents were forced to evacuate to temporary shelters in neighboring Nagaoka city for 2 months. Two types of temporary shelters were used: gymnasiums, and buildings with large separated rooms similar to community centers. A questionnaire survey and interviews (N=95) were conducted to elucidate problems of the living environment at the temporary shelters. This study analyzed acoustic environmental problems there. Noise‐related problems were noted by 40 respondents (46.5%): they were the fifth most frequently cited environmental problems. Several serious complaints, e.g., general annoyance at the shelters and footsteps of refugees at night, were only indicated by respondents who had evacuated to the gymnasiums. However, some problems, e.g., the clamor of children, including crying babies and voices of other refugees, were indicated by respondents irrespective of the type of the shelters to which they had been evacuated. Therefore, buildings like community centers were more desirable for temporary shelters, at least from the perspective of noise problems.