Table of Contents
ISRN Applied Mathematics
Volume 2011 (2011), Article ID 189735, 30 pages
http://dx.doi.org/10.5402/2011/189735
Research Article

Comparison of Two Approaches for Detection and Estimation of Radioactive Sources

1Physical Protection Section, Defence Research and Development Canada-Suffield, P.O. Box 4000 Stn Main, Medicine Hat, AB, Canada T1A 8K6
2Human Protection and Performance Division (HPPD), Defence Science and Technology Organization, 506 Lorimer Street, Fishermans Bend, VIC 3207, Australia
3Intelligence Surveillance and Reconnaissance Division (ISRD), Defence Science and Technology Organization, 506 Lorimer Street, Fishermans Bend, VIC 3207, Australia

Received 25 May 2011; Accepted 17 June 2011

Academic Editors: Y. Dimakopoulos and L. Guo

Copyright © 2011 Her Majesty the Queen in Right of Canada. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

This paper describes and compares two approaches for the problem of determining the number of radioactive point sources that potentially exist in a designated area and estimating the parameters of these sources (their locations and strengths) using a small number of noisy radiological measurements provided by a radiation sensor. Both approaches use the Bayesian inferential methodology but sample the posterior distribution differently: one approach uses importance sampling with progressive correction and the other a reversible-jump Markov chain Monte Carlo sampling. The two approaches also use different measurement models for the radiation data. The first approach assumes a perfect knowledge of the data model and the average background radiation level, whereas the second approach quantifies explicitly the uncertainties in the model specification and in the average background radiation level. The performances of the two approaches are compared using experimental data acquired during a recent radiological field trial.