Dayou Ma or Dah-you Maa, Chinese acoustic engineer (Beijing 01 March 1915 – Beijing 17 July 2012)

Authored about 200 papers and 20 books

Invented micro-perforated panel non-fibrous sound absorbers (1975) and microperforation jet mufflers

Analyzed sound decay in a rectangular room in terms of aerial vibration

Gave a formula of jet noise via air pressure and some empirical expressions for sound pressure levels and A-weighted sound levels of cold air jet noise

Presented a simplified method for calculations of normal modes for room acoustics i.e. a formula to describe the distribution of normal modes (1939)

HONORS

Gold Medal, Fraunhofer Society of Germany (1997)

Honorary Fellow, International Institute of Acoustics and Vibration (2001)