TY  - GEN
A1  - Bodnariuc, Ecaterina
ID  - heidok24515
N2  - This thesis is concerned with the development of methodological and mathematical foundations of plane wave ultrasound particle image velocimetry. This innovative
technology, also known as Echo PIV, is a non-invasive imaging technique developed to estimate the blood flow in the vascular system.

In this thesis, we address two relevant problems related to in-vitro Echo PIV. First, we consider the image reconstruction problem which amounts to estimating the location of small isolated scatterers, embedded in a homogeneous medium, from plane wave ultrasound measurements. We link the Delay and Sum method with the leastsquares
solution for the linearized inverse acoustic scattering problem. Numerical studies show that the least-squares approach provides accurate reconstruction results for synthetic and in-vitro data.

In the second part of the thesis, we focus on the motion estimation problem for pipe flow. For laminar and steady flow, we develop a global dictionary-based approach
that estimates the model flow parameter via an converging iterative refinement scheme. Furthermore, we show that the flow parameter can be the determined from the geometry
of the image sequence spectra. To discriminate between the steady and turbulent flow, we design a filter-bank that is sensitive to all flow directions and extract the local
velocity field by analyzing the phase component of the response function for combined filters. We validate our methods on synthetic and in-vitro data.
AV  - public
UR  - https://archiv.ub.uni-heidelberg.de/volltextserver/24515/
Y1  - 2018///
TI  - On Plane Wave Ultrasound Particle Image Velocimetry
ER  -