Conventional radiography produces a single image of an object by measuring the attenuation of an x-ray beam passing through it. When imaging weakly absorbing tissues, x-ray attenuation may be a suboptimal signature of disease-related information. In this paper we describe a new phase-sensitive imaging method, called multiple-image radiography (MIR), which is an improvement on a prior technique ...

Taking the discrete degree of bearing raceway grinding surface integrity as research object, orthogonal test based on wheel speed, workpiece speed and depth is designed. The residual stress, retained austenite, hardness, modified layer thickness roughness after were measured, mean value standard deviation these indexes calculated. results show that stress decreases with increase hardness keeps ...

This paper presents a hybrid simulator for the fast calculation of x-ray projections. Uncollided radiations are determined with a ray-driven method whereas the scattering signal is partitioned into single and multiple scattering, respectively estimated with an accelerated deterministic method and a coarse Monte Carlo simulation. The simulator takes into account the full acquisition chain, from ...

To recognize an object in an image, we must determine the best-fit transformation which maps an object model into the image data. In this paper, we propose a new alignment approach to recovering those parameters, based on centroid alignment of corresponding feature groups built in the model and data. To derive such groups of features, we exploit a clustering technique that minimizes intraclass ...

A 38 year old male patient presented to a radiology center for cone beam computed tomography (CBCT) and the working maxillofacial radiologist spotted a very peculiar finding There was a large piece of metal in the mandible (size 0.5 cm X 0.5 cm). Here in we have provided a commentary on CBCT artifacts seen in this case along with a short explanation on the source of metal. Based on our observat...

introduction: scatter radiation is one of the major sources of error in nuclear medicine data processing. different methods of scatter correction have been introduced in order to improve the quality of data. however the best method is to avoid recording of scatter photons in acquisition. the only difference between scattered and non-scattered photons is the energy. pulse height analyzer is the ...

A three-dimensional (3D) point-kernel multiple scatter model for point spread function (PSF) determination in parallel-beam single-photon emission computed tomography (SPECT), based on a dose gamma-ray buildup factor, is proposed. This model embraces nonuniform attenuation in a voxelized object of imaging (patient body) and multiple scattering that is treated as in the point-kernel integration ...

An X-ray computed tomography (CT) model based on the GEANT4 Monte Carlo code was developed for simulation of a cone-beam CT system for industrial applications. The full simulation of the X-ray tube, object, and area detector was considered. The model was validated through comparison with experimental measurements of different test objects. There is good agreement between the simulated and measu...