Oct 3 2025

Sensitivity volume as figure-of-merit for maximizing data importance in electrical impedance tomography

ECE 595 Seminar Series

October 3, 2025

2:00 AM - 12:00 PM

Location

Lecture Center C4

Address

802 S. Halsted St., Chicago, IL 60607

Sensitivity volume as figure-of-merit for maximizing data importance in electrical impedance tomography

Presenter: Matthew Grayson, Northwestern University

Abstract: Electrical impedance tomography (EIT) is a noninvasive imaging method whereby electrical measurements on the periphery of a heterogeneous conductor are inverted to map its internal conductivity. The EIT method proposed here aims to improve computational speed and noise tolerance by introducing sensitivity volume (SV) as a figure-of-merit for comparing EIT measurement protocols. Each measurement is shown to correspond to a sensitivity vector in model space, such that the set of measurements, in turn, corresponds to a set of vectors that subtend a sensitivity volume in model space. A maximal SV identifies the measurement protocol with the greatest sensitivity and greatest mutual orthogonality. A distinguishability criterion is generalized to quantify the increased noise tolerance of high sensitivity measurements. The SV method allows the model space dimension to be minimized to match that of the data space, and the data importance to be increased within an expanded space of measurements defined by an increased number of contacts. The reduction in model space dimension is shown to increase computational efficiency, accelerating tomographic inversion by several orders of magnitude, while the enhanced sensitivity tolerates higher noise levels up to several orders of magnitude larger than standard methods.

Speaker bio: Matthew Grayson is an expert in the design, fabrication, and electrical and thermoelectric characterization of electronic devices and materials. New methods in resistive tomographic imaging are being explored for 3D bioimaging as well as 2D artificial skin sensor applications. Laboratory measurement capabilities include electron transport over a continuous temperature range from 15 mK to 400 K, and high magnetic fields up to 17 T. Systems of interest are thermoelectrics, anisotropic conductors, cryogenic thermal management, and multivalley quantum systems. He completed his PhD studies at Princeton University with Professor Daniel Tsui studying tunnel spectroscopy of fractional quantum Hall effect edges. He then won a Humboldt Fellowship to research in Germany at the Walter Schottky Institut of the Technische Universitaet Muenchen. He joined Northwestern in 2007 and has been an associate professor since 2012, and full professor since 2018 in the Department of Electrical and Computer Engineering of Northwestern University.

Faculty host: Benjamin Sanchez Terrones, bst@uic.edu

Contact

ECE student affairs

Date posted

Oct 1, 2025

Date updated

Nov 20, 2025