Page 7 - Jan2013

FROM THE EDITOR
Dick Stern
Acoustical Society of America Melville, NY 11747
Once again it has been an honor to work with Veerle Keppens, Acoustics Today’s guest editor for this issue that focuses on physical acoustics. Veerle knows who to ask for an article and more to the point, who would be willing to say yes. The members of the Society owe her a debt of gratitude, as do I. Thank you Veerle.
Dick Stern
tissue. Understanding and optimizing the growth and collapse of these microbub- bles is expected to lead to improved diag- nosis and treatment at reduced costs. Nico Declercq reports on some recent results on the diffraction of sound by periodic structures. Periodic structures, be it Mayan pyramids or modern-day phonon- ic crystals, can function as acoustic prisms or frequency selective mirrors and hold promise for applications ranging from seismic wave deflection to accurate pas- sive filters used in electronics. The third article, by Martin Smith, Michael Roddewig, Kurt Strovink, and John Scales, shows how low-cost and off-the-shelf
materials can be used to build an active acoustic phased array with electronically-controlled time delays, a technolo- gy that is attractive for applications ranging from military target tracking radar systems to sophisticated medical imag- ing. I hope you will enjoy browsing through this issue and catch a glimpse of the intriguing work going on in the field of physical acoustics.
It has been a privilege and a pleasure
to be closely involved with this Acoustics
Today issue, focused on physical acoustics.
Broadly defined, physical acoustics is the
area of acoustics and physics that studies
interactions of sound waves with a medi-
um (solid, liquid, or gas). Determination
of the sound propagation in a medium is
often the choice technique to characterize
the medium and help understand its basic
properties. In addition, understanding
how changes in the physical properties of a
medium affect the propagation of the
acoustic wave is paramount when tailoring
a medium and/or the sound-medium
interaction for specific applications. The
articles featured in this issue highlight some of the fascinat- ing aspects of interaction of sound and media. Tom Matula and Hong Chen’s article focuses on “Microbubbles,” micron- sized gas-filled bubbles that play an important role in diag- nostic medical imaging. The bubbles act as very good ultra- sound scatterers, and because they oscillate upon ultrasound exposure they can do therapeutic work on the surrounding
6 Acoustics Today, January 2013
FROM THE GUEST EDITOR
Veerle M. Keppens
Department of Materials Science and Engineering University of Tennessee
Knoxville, Tennessee 37996