NOISE/NOTES (Dec 2019)

By Eoin A. King, NNI Editor, and
Brianna Cervello, NNI Social Media Assistant

NNI is on Facebook and Twitter. We try to keep our readers informed with noise news from all across the globe by highlighting interesting research and projects. Here is a roundup of some of the stories that have been making headlines. Follow @NNIEditor to stay up to date with all noise-related news!

Kidney Stones and Raindrops
The idea of a raindrop creating a crack in a windshield has led to a study that uses the same physics to pulverize kidney stones using sound waves. In a new paper published in Physical Review Research, Pei Zhong from Duke University, along with his former graduate student Ying Zhang, describes an experimental system to visualize the stress created by surface waves. The study put a lithotripsy device designed to shatter kidney stones with soundwaves in a vat of water covered by a sheet of glass, then set off a point-source explosion that expanded as a spherical shock wave. They were able to determine that the type of wave primarily responsible for most of the stress and damage, a leaky Rayleigh wave, propagates much faster than a second type of evanescent wave.

A Bioacoustic Fish Fence
A bioacoustic fish fence designed to herd migrating fish around water intakes and dams in Europe is being used in the state of Kentucky to deter the spread of invasive species in southern waters. The fence is a “behavioral barrier” that requires less maintenance than a physical barrier (such as a screen or an electric barrier). It releases bubbles and uses flashing lights and sound to influence the behavior of fish. A field trial of the fence is ongoing in Kentucky and will be in place for three years.

Crackdown on Fireworks in Scotland
The Times (UK) reports that authorities in Scotland are expected to announce strict restrictions on the private use of fireworks, to come into force next year. The restrictions are intended to reduce noise, stress on animals, and attacks on the emergency services.

Underwater Noise Pollution: The Ocean Noise Strategy
The National Oceanic and Atmospheric Administration (NOAA) recently released The Ocean Noise Strategy Roadmap, which seeks to ensure that NOAA more comprehensively addresses noise impacts to aquatic species and their habitat over the next 10 years. The road map is intended to serve as a high-level guide rather than a prescriptive listing of program-level actions. To discuss this, Michael Jasny, director of the Marine Mammal Protection Project, was recently interviewed on WNYC (in the US), and you can listen to that interview here.

Listen to What Mars Sounds Like
NASA has shared audio snippets of Martian quakes detected by the InSight lander earlier this year. The InSight lander was launched in 2018 and is designed to study the deep interior of Mars. Using a specialized seismometer called SEIS, the lander first detected shakes in April and has measured more than 100 rumblings since then.

A New Type of Wall . . .
Researchers at the University of Auckland (New Zealand) have been awarded almost $1 million to create a wall that would help reduce the transmission of low-frequency noises into neighboring rooms, while not taking up more floor space. They’ll be looking at how acoustics metamaterials and Helmholtz resonators can be used to improve the noise-insulating properties of the wall.

Turn Down That . . . Cinema!
Golden Globe winner Hugh Grant hit the headlines recently for complaining about the volume in the cinema. He asked, “Am I old, or is the cinema MUCH TOO LOUD?”The incident provoked an outpouring of accounts of aural pain at other venues, the Guardian (UK) reports.