title: Recognition of external object features in gas media using ultrasound transmission tomography.
abstract: The paper presents and analyzes a new way of recognizing external object features (shape, size, location) in gas media using ultrasound transmission tomography (UTT) with parallel-ray-projection scanning geometry. The concept of UTT in a gas medium is close to classical tomography, however because of the nature of the measurement environment, visualizing the internal structure of solid objects is difficult; whereas it is possible to image their external features: their shape, size and spatial location. The paper presents the results of examining the shape, size and location of different objects in the air in the form of tomographic images, obtained in parallel-ray-projection geometry, using a specially elaborated research setup for UTT. Applying parallel-ray-projection geometry enabled us to investigate the influence of scanning resolution on image quality. In order to test the operation of the elaborated algorithm of tomographic image reconstruction on the basis of correct measurement data, special software was written for simulating the binary matrix of the measurements for a set of a dozen or so solid objects of different shapes and a few simulations were performed.
authors.affiliation: Institute of Telecommunications, Teleinformatics and Acoustics, Wroclaw University of Technology, Wybrzeze Wyspianskiego 27, 50-370 Wroclaw, Poland. krzysztof.opielinski@pwr.wroc.pl <krzysztof.opielinski@pwr.wroc.pl>
authors.forename: Krzysztof J
authors.initials: KJ
authors.lastname: Opielinski
authors.forename: Tadeusz
authors.initials: T
authors.lastname: Gudra