Sound absorption by metallic foam after triaxial hydrostatic compression.

An engineering method for triaxial hydrostatic compression of metallic foam is presented to preferentially alter the foam's microstructure. The method is demonstrated on an assortment of open-cell aluminum foams with varying pore size and porosity. Measurements of acoustic absorption indicate that the compressed samples absorb significantly more sound than the conventional samples of equal thickness in the test range from 0.

Evaluating hospital soundscapes to improve patient experience.

Hospital soundscapes can be difficult environments to assess acoustically due to alarms, medical equipment, and the continuous activity within units. Routinely, patients perceive these soundscapes to be poor when rating their hospital experience on HCAHPS (Hospital Consumer Assessment of Healthcare Providers and Systems) surveys administered after discharge. In this study, five hospital units of widely varying HCAHPS "quietness" performance were analyzed.