Perspectives on wanted and unwanted sounds in outdoor environments Studies of masking, stress recovery, and speech intelligibility Jesper Alvarsson To my too tolerant partner and children vii Abstract An acoustic environment contains sounds from various sound sources, some generally perceived as wanted, others as unwanted. This thesis examines the effects of wanted and unwanted sounds in acoust...

A laboratory study was conducted to determine the e ects of sonic boom signature shaping on subjective loudness and acceptability . The study utilized the sonic boom simulator at the Langley Research Center. A wide range of symmetrical, front-shock-minimized signature shapes were investigated together with a limited number of asymmetrical signatures. Subjective loudness judgments were obtained ...

AIM  To evaluate the sound pressure level to which preschool students are exposed. METHOD  This was a prospective, quantitative, nonexperimental, and descriptive study. To achieve the aim of the study we used an audio dosimeter. The sound pressure level (SPL) measurements were obtained for 2 age based classrooms. Preschool I and II. The measurements were obtained over 4 days in 8-hour session...

BACKGROUND Intensive care units (ICUs) in human hospitals are consistently noisy environments with sound levels sufficient to substantially decrease sleep quality. Sound levels in veterinary ICUs have not been studied previously, but environmental sound has been shown to alter activity in healthy dogs. HYPOTHESIS Veterinary ICUs, like those in human medicine, will exceed international guideli...

Directional loudness is that phenomenon by which the loudness of a sound may vary according to the localization of its source. This phenomenon has been mainly observed for high-frequency sounds, for sources located in the horizontal plane. Because of the acoustic shadow of the head, the left and right ear pressures are modified depending on the source azimuth and the global loudness resulting f...