Computer simulations have been successfully employed in the development, assessment, and refinement of X-ray systems. However, many of these simulation tools have either been too slow, too complicated, or not capable of addressing the problem at hand. To address these issues, we introduce a fast flexible simulation tool, QSimRT that inherently interfaces with existing three-dimensional (3D) model creation tools (such as Blender) and utilizes state-of-the-art raytracing hardware and algorithms. The implementation of realistic X-ray simulation is multifold: our solution faithfully models the 3D, volumetric shapes, X-ray material properties, and packing structures of virtual items, accurately and efficiently simulates the X-ray physics, and can generalize to a breadth of X-ray measurement architectures, including AT, CT, air cargo, and cargo portal. In this talk, we demonstrate how our method yields realistic simulations, comparable to real-world data.

The task of threat detection in X-ray based security screening applications not only demands a high probability of detection (Pd) but also low probability of false alarm (Pfa) to reduce operational cost and inconvenience. While material classification based on X-ray transmission-based features (i.e., material density and effective atomic number (Zeff)) have been demonstrated to yield high Pd but they suffers from relatively high Pfa due to the lack of material specificity especially in and around threat materials. It is also well known that X-ray coherent diffraction based material measurement are capable of providing more specific material information, at the molecular level, complementary to transmission based material information. In this work we report on the performance of joint classifiers, specifically support vector machines, that combine X-ray transmission with coherent diffraction features and quantify the improvement relative to transmission only system.

To allow for fast, automated inspection of checked baggage with low false alarm rates, we designed and built a novel X-ray diffraction (XRD) system to use in a hybrid CT+XRD configuration, where each bag is scanned by both CT and XRD systems. Our XRD system is modular, vendor agnostic, and operates inline with the CT system at belt speed with full-tunnel coverage. In this work, we demonstrate reduced false alarm rates (relative to CT alone) with our XRD system placed inline and integrated mechanically and via software with a Smiths CTX 5800 (a certified EDS system) for fully-automated material-based alarm decisions.

Rapiscan Systems, Inc., has developed a real-time tomography (RTT) stationary-gantry CT system to fulfill TSA requirements for screening accessible property at speed of the passenger. Similar in concept to the Rapiscan RTT110 stationary-gantry CT system for hold-baggage, the newly developed smaller tunnel system has been redesigned from the ground up. The goal is to achieve a high-speed, small-footprint and low-cost system that exceeds the performance of currently deployed dual-view checkpoint systems.