Four researchers from Research Center for Ultrasonics and Technologies of the Institute of Acoustics, Chinese Academy of Sciences attended the International Congress on Ultrasonics (ICU) in May. They were Prof. LIN Weijun, Associate Prof. BAI Lixin, Associate Prof. ZHANG Xiumei and Assistant Prof. SU Chang.

This congress was held in Metz, France and hosted by Georgia Tech Lorraine together with the French Acoustical Society. Around 700 researchers from 53 countries participated in the congress.

There were 9 plenary and keynote lectures, 410 oral and 170 poster presentations in 95 scientific sessions with a maximum of 9 parallel sessions.

Topics in this congress covered physical acoustics, bio-medical ultrasound imaging and therapy, NDT, acoustopotic interactions, acoustic waveguide, standing wave and resonating, piezoelectrics and transducers, chemical and molecular ultrasonics, phononic crystals and metamaterials, waves in granular media, soft tissue quantitative ultrasound, instrumentation and so on.

The plenary and keynote sessions included topics such as wave propagation in complex media and its applications, cavitation, phononic crystals, NDT, etc. The plenary lecture “Time-Reversal: from acoustics to optics” given by Prof. M. Fink, systematically introduced time reversal theories. Combining applications of time reversal with acoustics and optics, Prof. M. Fink introduced principle and method of superresolution and showed some recent developments.

Another plenary lecture “Intramembrane cavitation” by Prof. E. Kimmel discussed phenomenon of ultrasound interaction on body tissues, from both experimental and theoretical aspects. He discussed physical mechanisms under different ultrasound intensities in diagnose with no cavitation and in therapy with cavitation, and further explored kinetics mechanism of cavity on a double membrane cell model.

During the congress, researchers from our institute presented their research progress in different sessions. Prof. LIN Weijun delivered a presentation of “Numerical study of mode waves in a deviated borehole penetrating a transversely isotropic formation”, which reported achievements and progress on analyzing dispersion properties of mode waves in a deviated borehole penetrating a transversely isotropic formation. Besides, inversing anisotropic parameters of formation from sonic logging data based on the analysis was introduced.

Associate Prof. BAI Lixin’s presentation “Memory effect and redistribution of cavitation nuclei” introduced the memory effect of a special cavitation structure in fluid thin layer. He achieved the longest memory effect so far, based on which he proposed a method to control the redistribution of micro-bubbles.

The poster “Imaging of geological conditions ahead of drill bit using a drilling hole dipole source” was presented by Associate Prof. ZHANG Xiumei, in which she introduced directivities of different mode waves in the far field of a dipole source in a drilling hole. In the following, based on the analysis of acoustic wave response from different reflective interfaces, progress on the inversion of geological conditions ahead of drill bit from the received waves was given.

Assistant Prof. SU Chang’s poster “Iterative time reversal simulation for selective focusing in multi-target nonlinear media” showed numerical simulation results of the iterative time reversal for selective focusing in multi-target nonlinear media. Also, she discussed the impacts of nonlinearity on ultrasound focusing with time reversal.

The newest progress on ultrasound theory and applications was displayed on this congress, as well as the current problems and difficulties. Communication with experts from all over the world inspired us much.

The 2015 International Congress on Ultrasonics, one of the biggest international conferences on ultrasonics, is part of tradition and sequence of congresses, dating back to 1993. It is comprised of the World Congress on Ultrasonics (WCU), Ultrasonics International (UI), and “UI+WCU” (later renamed as ICU). This event takes place every two years. And the 2017 ICU will be held in Honululu, Hawaii, USA.

Our four researchers attending the 2015 International Congress on Ultrasonics in Metz, France

Our researchers presenting their research progress

(Source: SU Chang from the Research Center for Ultrasonics and Technologies)