論文(共著)が Acoustical Science and Technology に受理されました。

音響周波数応答に基づいて部屋の温度を推定する手法を開発した論文(共著)が Acoustical Science and Technology に受理されました。

A. Hayashida, Y. Mizuno, and K. Nakamura, “Estimation of room temperature based on acoustic frequency response,” Acoust. Sci. Technol., in press.

Monitoring various kinds of ‘states’ of rooms is highly required for a number of reasons. First, to detect the state of persons is one of the most important applications. Activity or health condition of persons in a room has become a major issue to be watched in aging societies of developed countries. Use of surveillance cameras is not an acceptable way on account of privacy protection. Acoustic surveillance has been studied as an alternative method, where the sounds generated by persons’ activities are passively detected and analyzed using sophisticated signal processing. Second, the physical states of a room itself need to be monitored for purposes of security and air conditioning. It is useful to detect from a remote place whether the windows or doors of the room are open or closed. To achieve this, every window/door needs to be equipped with a sensor. The temperature of the room is also essential information for air conditioning and for detecting fire or excessive heat. In this letter, we attempt to measure the temperature and its distribution in a room based on the acoustic responses. The point of this study is that it focuses on the modal responses of the room instead of the directive detection with microphone arrays. The measurement system is composed of one loudspeaker and one microphone, which obtain the acoustic frequency responses of the room; they will be replaced by a smart speaker or a similar device in future. First, the measurement principle is explained. Second, the method is demonstrated using a 1/8-scaled model. Finally, a trial for a practical room is performed.