"Detecting Nuclear Materials Smuggling: Using Radiography to Improve Container Inspection Policies,"
Parsons Seminar Series, Texas A&M University, September 21, 2009.
This paper proposes a
layered container inspection system
for detecting illicit nuclear materials using radiographyinformation.
We argue that the current inspection system, relying
heavily on the Automated Targeting System (ATS) and passive
radiation detectors, is inherently incapable of
reliably detecting shielded radioactive materials,
especially highly enriched uranium (HEU). This motivates the
development of a new inspection system, which is designed
to address a fundamental flaw of the ATS-based system, allowing for
improved defense against sophisticated adversaries. In the
proposed inspection system, all
cargo containers go through x-ray imaging equipment
first. From the x-ray image, a hardness measure of
the container is computed. This hardness measure
characterizes how likely it is that shielded HEU, if it does exist
in the container, will not be detected in a subsequent passive
detection step. Depending on the value of the hardness, the
lower-hardness containers are sent to passive detection
and the high-hardness containers are sent directly to
active detection. This paper explores the trade-off between the
detection probability of the new inspection system and
the expected sojourn time a container spends in the
system. The solution details and decision-making tools
for using such a system are provided. Comparisons are
made between the proposed system and the current
ATS-based nuclear inspection system.
Associated Project(s):SHIELD (Smuggled HEU Interdiction through Enhanced anaLysis and Detection): A Framework for Developing Novel Detection Systems Focused on Interdicting Shielded HEU