Aero-engine noise reduction has always been a critical challenge in the field of science and
engineering. Passive acoustic liners are considered one of the most effective structures for …

Membrane-type acoustic metamaterials (MAM) are novel, lightweight and compact materials
that can be used to isolate the sound at low frequencies beyond the limits of conventional …

A balloon dielectric elastomer actuator (DEA) speaker is constructed by forming a disk-
shaped DEA film into a sphere using air, increasing its surface area by 3033%. Sound is …

This paper describes a duct mounted with multiple hybrid Helmholtz resonators (HHRs) for
low-frequency noise control in a piping system. The newly designed HHR is composed of a …

Most membrane-type acoustic absorbers for low-frequency sound attenuation are applicable
only at a fixed resonant frequency for a narrow bandwidth. Tuning of the acoustic absorption …

An adjustable sound absorption frequency honeycomb-microperforated panel (ASAFHM)
structure is designed in this study. The ASAFHM structure is a unit of a honeycomb …

Window glasses can block noise from outdoor, but they reverberate sound within a large
indoor space. Microperforated glass absorbers have been developed to absorb sound over …

Acoustic metasurfaces display significant potential for controlling sound waves by using
subwavelength structures. However, serious shortcomings are evident regarding the sound …

Dielectric elastomer actuator (DEA)-based unimorphs that actively bend in one direction,
can mimic the blooming motion of flower petals. Here we explore an application of such …

Whether intentionally generating acoustic waves or attempting to mitigate unwanted noise,
sound control is an area of challenge and opportunity. This study investigates traditional …