Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Detecting Electric Devices in 3D Images of Bags   The aviation and transport security industries face the challenge of
screening high volumes of baggage for threats and contraband in the minimum
time possible. Automation and semi-automation of this procedure offers the
potential to increase security by detecting more threats and improve the
customer experience by speeding up the process. Traditional 2D x-ray images are
often extremely difficult to examine due to the fact that they are tightly
packed and contain a wide variety of cluttered and occluded objects. Because of
these limitations, major airports are introducing 3D x-ray Computed Tomography
(CT) baggage scanning. We investigate whether we can automate the process of
detecting electric devices in these 3D images of luggage. Detecting electrical
devices is of particular concern as they can be used to conceal explosives.
Given the massive volume of luggage that needs to be screened for this threat,
the best way to automate the detection is to first filter whether a bag
contains an electric device or not, and if it does, to identify the number of
devices and their location. We present an algorithm, Unpack, Predict, eXtract,
Repack (UXPR), which involves unpacking through segmenting the data at a range
of scales using an algorithm known as the Sieve, predicting whether a segment
is electrical or not based on the histogram of voxel intensities, then
repacking the bag by ensembling the segments and predictions to identify the
devices in bags. Through a range of experiments using data provided by ALERT
(Awareness and Localization of Explosives-Related Threats) we show that this
system can find a high proportion of devices with unsupervised segmentation if
a similar device has been seen before, and shows promising results for
detecting devices not seen at all based on the properties of its constituent
parts.

17
The categories of this paper are: q-fin
3
The categories of this paper are: physics
32
The categories of this paper are: atom-ph
35
The categories of this paper are: mtrl-th
21
The categories of this paper are: adap-org
26
The categories of this paper are: bayes-an
12
The categories of this paper are: nucl-th
9
The categories of this paper are: nlin
22
The categories of this paper are: chao-dyn
0
The categories of this paper are: hep-ph
34
The categories of this paper are: chem-ph
30
The categories of this paper are: q-alg
18
The categories of this paper are: econ
36
The categories of this paper are: cmp-lg
23
The categories of this paper are: solv-int
27
The categories of this paper are: comp-gas