Molecular structure of a crystal may be solved based on at least two diffraction tilt series acquired from a sample. The two diffraction tilt series include multiple diffraction patterns of at least one crystal of the sample acquired at different electron doses. In some examples, the two diffraction tilt series are acquired at different magnifications.

A method for assigning one of a safe and threat condition to an object includes determining density and effective atomic number values for a plurality of predetermined safe and threat objects, plotting the values in a probability map to correlate corresponding density and effective atomic number values with each of the safe and threat objects, scanning an object to provide dual-energy attenuation images representing the object, decomposing the attenuation images into dual-reference material equivalent path length images to provide reference material equivalent path lengths representing the object, converting the reference path lengths into object path lengths, determining the effective atomic number for each pixel representing the object, and, imposing the effective atomic number and the mass density of the unknown object onto the probability map to determine a probability that the object is correlated with one of the predetermined safe and threat objects.

There is provided a method for assigning an attribute to x-ray attenuation including the steps of acquiring first and second reference material equivalent path length information associated with a first range of dual-energy x-ray attenuation information, acquiring second and third reference material equivalent path length information associated with a second range of dual-energy x-ray attenuation information, and, joining the first the first dual-energy x-ray attenuation information range with the second dual-energy x-ray attenuation information range using coefficients representing dual-energy x-ray attenuation information of the second reference material to define a third dual-energy x-ray attenuation information range upon which may be imposed dual-energy x-ray attenuation values within the third dual-energy x-ray attenuation information range to determine corresponding first reference material equivalent path lengths and third reference material equivalent path lengths.

There is provided a method for assigning an attribute to x-ray attenuation including scanning in an x-ray scanning device first and second reference materials each having known atomic composition, dimensions and orientation in the scanning device. The device emits x-rays which pass through the first reference material with first reference material path lengths and the second reference material with second reference material path lengths. The x-rays are detected by detectors to provide a plurality of dual-energy attenuation images having dual-energy x-ray attenuation information. The dual-energy x-ray attenuation information in the dual-energy attenuation images is associated with the first and second reference material path lengths. Then, each of the first and second reference material path lengths are expressed collectively as a function of the associated attenuation information to define attenuation surfaces upon which may be imposed dual-energy attenuation values to determine corresponding first and second reference material equivalent path lengths.

A method for assigning attributes to an unknown object includes the steps of scanning the unknown object at least partially overlapping with a background object within an x-ray scanning device to provide dual-energy attenuation images having dual-energy attenuation information representing an overlap region wherein the background object and the unknown object overlap, decomposing the attenuation images into reference material equivalent path length images, removing the background object to provide reference material equivalent path lengths representing the unknown object, converting the reference material equivalent path lengths representing the unknown object into unknown object path lengths multiplied by a predetermined scaling factor, reducing the scaling factor to provide a contour of the unknown object and unknown object path lengths, and, determining a density and effective atomic number of the unknown object.

There is provided a method for assigning an attribute to an unknown object overlapping with a predetermined background object. The unknown object is scanned overlapping with the background object within an x-ray scanning device to obtain a plurality of dual-energy attenuation images having attenuation information representing the background object and an overlap region wherein the background object and the unknown object overlap. The dual-energy attenuation images are decomposed into reference material equivalent path length images. The reference material equivalent path lengths representing the background object in the overlap region are determined and eliminated from the overlap region to provide reference material equivalent path length images having first and second reference material equivalent path lengths through only the unknown object.

An inspection system (100) having: a source (101) configured to generate inspection radiation (40); a collimator (103) configured to collimate the inspection radiation into an inspection beam (41) configured to irradiate a section of a vehicle (20); a filter (102) located between the source and the collimator, the filter having at least a cargo configuration and an attenuation configuration; and a controller (104) configured to control the configuration of the filter, such that the filter is in the cargo configuration when the inspection beam irradiates a container (23), and in the attenuation configuration when the inspection beam irradiates a cabin (21).

Methods and system for decomposing a high-energy dual-energy X-ray CT material are disclosed. In the method, two types of effect such as Compton effect and electron pairing effect which dominates are reserved and the influence of the other effect such a photoelectric effect is removed so as to improve the accuracy of the material decomposition. The unique advantage of the present disclosure is to effectively remove the error of the calculated atomic number Z due to directly selecting two effects during processes of material decomposition in the conventional dual-energy CT method. This may greatly improve the accuracy of dual-energy CT identification of the material, and it is important to improve the conventional dual-use CT imaging system applications, such as clinical therapy, security inspection, industrial non-destructive testing, customs anti-smuggling and other fields.

A tomography method includes: a step of having a photon counting detector to undergo a relative motion with respect to an X-Ray source, and capturing 2?N projected energy spectral data at 2?N individual discrete projection angles that divide the relative motion, the N being a positive integer; a step of reforming the 2?N projected energy spectral data at the 2?N individual discrete projection angles and establishing corresponding projection intensity data; and, a step of basing on the projection intensity data and the 2?N projected energy spectral data at the 2?N individual discrete projection angles to calculate the material decomposition images. In addition, a tomography system is also provided.

This disclosure relates to a system and method for detecting an item having at least one symmetry property inside an inspection object based on at least one transmission image. The method includes the steps: (a) detection of edges of individual items contained in the transmission image in order to produce an edge image; and (b) detection of the item by determining a symmetry line that can be associated with an item with at least one symmetry property contained in the transmission image based on pairs of edge picture elements of the edge image that are positioned symmetrically to each other relative to the symmetry line; and in step (b), in determining the symmetry line in the edge image, the only edge picture elements that are taken into account are those for which the symmetry line lies in an item contained in the transmission image, to which item the edge belongs.