摘要:
An x-ray technique-based nonintrusive inspection apparatus is provided which is capable of inspecting 600 containers an hour which is small, and which is easily maintainable. Features of the apparatus include “radiation locking” with “active curtains”, “continuous scanning” utilizing an x-ray line scanner subsystem and a CT scanner subsystem, good structural integrity, radiation containment in a self-shielding manner, an easily maintainable driving arrangement, shielding curtains that can be raised and lowered quickly, a container jam release mechanism, and efficient air conditioning.
摘要:
A nonintrusive inspection apparatus is described of the kind having a base frame, an elongated shield on the base frame, a conveyor belt passing through the shield which is used for transporting closed containers, and a rotating CT scanner subsystem which is used for scanning the container on the conveyor belt. The CT scanner subsystem is mounted through the shield to the base frame. The shield provides sufficient rigidity for the CT scanner subsystem. A cover is positioned over the CT scanner subsystem, but only over a portion of the shield, thereby allowing for a person on one side of the shield to see a person on an opposite side of the shield.
摘要:
A method and apparatus is disclosed for mapping the relevant material properties of a log, such as knot location and extent. The outer shape of the log under bark is also revealed using this method, and the boundary between the heartwood and sapwood is accurately mapped. The apparatus includes three x-ray sources and arrays of x-ray detectors, for measuring the attenuation of the wood in the log. Deviations in attenuation are related to changes in density, which are indicative of knots and other defects. Accurate estimates of shape, density and knot location render improved sawing decisions at the headrig of a sawmill, which improve the yield of high quality lumber from a given log. The techniques may also be used in a system for sorting logs according to quality.
摘要:
This invention relates to an x-ray based non-intrusive inspection apparatus. An x-ray source is mounted to a gantry and provides x-rays that transmit through an object. The x-rays have an included angle between first and second shadow lines. A circle of reconstruction is formed upon rotation of the gantry having a radius from a center axis of rotation of the gantry to a closest point on the first shadow line. The second shadow line passes through the center axis so that x-rays transmit through only half of the circle of reconstruction at any given moment. The entire volume within the circle of reconstruction is scanned due to rotation of the gantry. Such an assembly allows for the x-ray source to be placed closer to the center axis of rotation of the gantry without reducing the radius of the circle of reconstruction.
摘要:
In one embodiment, the invention provides a method for mounting a plurality of detector modules to a rotatable gantry structure for an x-ray detection machine. The method comprises mounting the plurality of detector modules end-to-end to define a stair-step configuration in an x-ray detection zone of the rotatable gantry structure.
摘要:
An x-ray technique-based nonintrusive inspection apparatus is provided which is capable of inspecting 600 containers an hour which is small, and which is easily maintainable. Features of the apparatus include “radiation locking” with “active curtains”, “continuous scanning” utilizing an x-ray line scanner subsystem and a CT scanner subsystem, good structural integrity, radiation containment in a self-shielding manner, an easily maintainable driving arrangement, shielding curtains that can be raised and lowered quickly, a container jam release mechanism, and efficient air conditioning.
摘要:
An x-ray-based nonintrusive inspection apparatus has a collimator shield. An adjusting actuator is actuable to move the collimator shield between a pre-scanning position and a CT scanning position, in the pre-scanning position, the collimator shield exposing a smaller portion of a respective crystal to the x-rays than in the CT scanning position. A controller is connected to a gantry motor and the adjusting actuator. The controller controls the motor and the adjusting actuator such that the collimator shield is in the pre-scanning position when a gantry is stationary and in the CT scanning position when the gantry is rotating.
摘要:
An apparatus for detecting concealed objects, such as explosives, drugs, or other contraband is disclosed. The apparatus uses CT scanning to identify concealed objects with a density corresponding to the density of a target object such as explosives or drugs. To reduce the amount of CT scanning required, a number of prescanning approaches are disclosed. Based upon the prescan data, selected locations for CT scanning are identified. CT scanning is undertaken at the selected locations. The resultant CT scan data is utilized to automatically identify objects of interest. This identification of objects may be verified through further automatic analysis of such attributes as shape, texture, and context. Finally, the objects of interest may be reconstructed and displayed on a computer monitor for visual analysis by an operator.