My research focuses on direct and inverse problems involving wave motion. Example topics include inverse scattering, waves in periodic and random media, geodynamics, and nonlinear waves in soft solids. We tackle the scientific and engineering challenges using analytical, computational, and experimental tools. Target applications of our work include nondestructive evaluation (NDE) of materials and structures, seismic imaging, medical diagnosis, and design of metamaterials.
High-frequency inverse scattering

This study [61] deciphers the Topological Sensitivity (TS) as a tool for 3D anomaly reconstruction in the high-frequency regime. The video plots the TS distribution in a mid-section of an ellipsoidal anomaly with increasing (in-plane) source aperture, indicated by the dial. As shown by the analysis, the extreme TS values trace the boundary of a scatterer.

Research openings 2018/19
Waveform tomography of a hard defect

Here [36], we pursue 3D seismic waveform tomography of a semi-infinite solid using surface observations. The video shows the evolution of a trial heterogeneity during nonlinear minimization, whose color indicates the inclusion's shear modulus. The modulus of the background solid (resp. true anomaly) is G=1 (resp. G=4).

Research openings 2018/19
My research focuses on direct and inverse problems involving wave motion. Example topics include inverse scattering, waves in periodic and random media, geodynamics, and nonlinear waves in soft solids. We tackle the scientific and engineering challenges using analytical, computational, and experimental tools. Target applications of our work include nondestructive evaluation (NDE) of materials and structures, seismic imaging, medical diagnosis, and design of metamaterials.
Waveform tomography of a soft defect

Here [36], we pursue 3D seismic waveform tomography of a semi-infinite solid using surface observations. The video shows the evolution of a trial defect during nonlinear minimization, whose color indicates the inclusion's shear modulus. The modulus of the background solid (resp. true anomaly) is G=1 (resp. G=0.2).

Research openings 2018/19
My research focuses on direct and inverse problems involving wave motion. Example topics include inverse scattering, waves in periodic and random media, geodynamics, and nonlinear waves in soft solids. We tackle the scientific and engineering challenges using analytical, computational, and experimental tools. Target applications of our work include nondestructive evaluation (NDE) of materials and structures, seismic imaging, medical diagnosis, and design of metamaterials.
Ultrasonic waves in an aluminum plate

Waves & Imaging Lab at the University of Minnesota: 3D Scanning Laser Doppler Vibrometer (SLDV) capture of the plane-stress wavefield in an aluminum plate containing a hole and a slit (ux displacement component, source wavelet w/center frequency @100kHz).

Research openings 2018/19
My research focuses on direct and inverse problems involving wave motion. Example topics include inverse scattering, waves in periodic and random media, geodynamics, and nonlinear waves in soft solids. We tackle the scientific and engineering challenges using analytical, computational, and experimental tools. Target applications of our work include nondestructive evaluation (NDE) of materials and structures, seismic imaging, medical diagnosis, and design of metamaterials.
Seismic waves across a stationary fracture

Waves & Imaging Lab at the University of Minnesota: 20kHz ultrasonic waves propagating across a stationary through-fracture in a granite slab: out-of-plane (uz) displacement waveforms captured by SLDV.

Research openings 2018/19
My research focuses on direct and inverse problems involving wave motion. Example topics include inverse scattering, waves in periodic and random media, geodynamics, and nonlinear waves in soft solids. We tackle the scientific and engineering challenges using analytical, computational, and experimental tools. Target applications of our work include nondestructive evaluation (NDE) of materials and structures, seismic imaging, medical diagnosis, and design of metamaterials.
Seismic waves across an advancing fracture

Waves & Imaging Lab at the University of Minnesota: 20kHz ultrasonic waves propagating across an advancing fracture in a granite slab subjected to 3-point bending: in-plane (uy) displacement waveforms captured by SLDV.

Research openings 2018/19
My research focuses on direct and inverse problems involving wave motion. Example topics include inverse scattering, waves in periodic and random media, geodynamics, and nonlinear waves in soft solids. We tackle the scientific and engineering challenges using analytical, computational, and experimental tools. Target applications of our work include nondestructive evaluation (NDE) of materials and structures, seismic imaging, medical diagnosis, and design of metamaterials.