Autori: M. Iovea, M. Neagu, O. Duliu, G. Mateiasi

Editorial: International Symposium on Digital Industrial Radiology and Computed Tomography (DIR 2007) held in June 2007 in Lyon France, 2007.

Rezumat:

The experiments using our laboratory dual-energy X-Ray Radioscopy/Tomography equipment reveals an accuracy better than 2% in measuring Zeffective and around 5% in the weight measurement. In “dualenergy” X-ray tomography (CT) accuracy better than 3% in measuring Zeffective and Density of scanned objects and less than 2% accuracy in materials identification (using also the attenuation coefficients comparison) has been obtained. Due too the high accuracy of both methods is it feasible to discriminate between water (or other typical standard organic materials found in baggage) and the liquid explosives. Also, by applying both methods successively, a much lower false positive alarm rate could be reached. Both techniques have been successfully checked using simulated explosives samples (manufactured by Xray NESTT Co.- USA) having known values of Zeffective and Density. Further, we present the simulated encouraging results of a new iterative reconstruction algorithm intended for replacing the actual rotational-based CT scanning method with a linear movement scan. The new algorithm is a combination of a classical ART with a fast ray-tracing algorithm for evaluation of rays’ pixels contribution. The main goal of the algorithm is to develop a new X-Ray CT machine for luggage control within the size and the cost of the actual standard X-Ray screening devices.

Cuvinte cheie: Dual-energy, CT, radioscopy, Effective Atomic number, luggage, screening, explosive

URL: http://www.ndt.net/article/dir2007/papers/16.pdf