130 results about "Fractography" patented technology

A system and method for tomographic image reconstruction using truncated limited-angle projection data that allows exact interior reconstruction (interior tomography) of a region of interest (ROI) based on the linear attenuation coefficient distribution of a subregion within the ROI, thereby improving image quality while reducing radiation dosage. In addition, the method includes parallel interior tomography using multiple sources beamed at multiple angles through an ROI and that enables higher temporal resolution.

Tomography by emission of positrons (pet) system dedicated to examinations of human body parts such as the breast, axilla, head, neck, liver, heart, lungs, prostate region and other body extremities which is composed of at least two detecting plates (detector heads) with dimensions that are optimized for the breast, axilla region, brain and prostrate region or other extremities; motorized mechanical means to allow the movement of the plates under manual or computer control, making it possible to collect data in several orientations as needed for tomographic image reconstruction; an electronics system composed by a front-end electronics system, located physically on the detector heads, and a trigger and data acquisition system located off-detector in an electronic crate; a data acquisition and control software; and an image reconstruction and analysis software that allows reconstructing, visualizing and analyzing the data produced during the examination.

An ⁸²Sr/⁸²Rb generator column is made using a fluid impervious cylindrical container having a cover for closing the container in a fluid tight seal, and further having an inlet for connection of a conduit for delivering a fluid into the container and an outlet for connection of a conduit for conducting the fluid from the container. An ion exchange material fills the container, the ion exchange material being compacted within the container to a density that permits, the ion exchange material to be eluted at a rate of at least 5 ml/min at a fluid pressure of 1.5 pounds per square inch (10 kPa). The generator column can be repeatedly recharged with ⁸²Sr. The generator column is compatible with either three-dimensional or two-dimensional positron emission tomography systems.

A system and method for specificity-based multimodality three-dimensional optical tomography imaging comprises steps of: optical imaging to obtain a light intensity of body surface optical signal of an imaging target; CT imaging to obtain structure volume data; establishing an equation representing a linear relationship between the distribution of the obtained light intensity of body surface optical signal of the imaging target, the obtained CT discrete mesh data and the distribution of unknown internal self-luminescence light sources; establishing a dynamic sparse regularization target function in every iteration for the equation; and reconstructing a tomography image. The present invention well considers the optical specificity of tissue, in which there is a non-uniform optical characteristic parameter distribution within the same tissue when finite element modeling is used, which is closer to the real situation, so that an accurate imaging effect is achieved.

The invention discloses a three-dimensional reconstruction method for a concrete CT (computed tomography) image, comprising the following steps of: firstly, performing tomography on a concrete test sample by a CT machine; secondly, performing three-dimensional reconstruction on the concrete CT image by using a ray-casting algorithm, so as to obtain real images of aggregates, mortar and holes; and finally, performing three-dimensional stereo reconstruction on the concrete CT image by using a visualization tool VTK (visualization tool kit). The three-dimensional reconstruction method for the concrete CT (computed tomography) image, disclosed by the invention, has the advantages of being strong in real-time performance, high in operation efficiency, and capable of clearly and reliably distinguishing the aggregates, the mortar and the holes. A real meso-structure model of concrete can be obtained through a three-dimensional reconstruction result, the three-dimensional reconstruction result can be subjected to a test comparison with a concrete mesoscopic numerical simulation result, and a numerical analysis model is corrected.

The invention relates to individualized mandible prosthesis of titanium alloy and a preparation method, which is applicable to a field of coaptation and repairing after a defect and loss of the mandible caused by injuries or tumors, etc. The individualized mandible prosthesis essentially consists of a substitute of a defected or lost part and connecting and positioning wing spans. The prosthesis is characterized in that the whole mandible of a patient is scanned by a CT or MRI fault scan; after processing the graph and image, soft tissues and hard tissues are separated according to the fault scan graph, thus a three-dimensional reconstruction of the mandible of the patient is realized; according to biological symmetry principle, a model of the unimpaired side of the mandible of the patient is used for a mirror image processing so as to obtain a mandible prosthesis model of the lost side of the mandible of the patient; the data of the prosthesis model are transformed and the connecting and fixing wing spans are designed on the model; a processing order of the model is input into a CNC processing center and the substitute prosthesis of the mandible of the patient is directly cut out. The mandible prosthesis produced by the invention has a good dynamic capacity and biological dynamic characteristics; the problem of an individualized match is directly solved; and the prosthesis is excellently matched with the mandible of the patient.

A compact and mobile gantry for 3-dimensional Application Specific Emission and/or Transmission Tomography (ASETT) imaging of the breast in single photon or coincidence emission modes, and single photon, or coincidence, or x-ray transmission modes. While the ASETT gantry was designed, built and evaluated for imaging metabolically active lesions in the pendant breast, it can also be used to image other organs and objects. This system overcomes physical constraints associated with imaging a pendulous breast in prone patients, while simultaneously satisfying sampling criteria for sufficient data collection in the pendulous breast reference frame. When combined with an offset cone-beam tomographic x-ray transmission imaging system, this dual modality ASETT system could provide simultaneous and coregistered structural and functional information about large or dense breasts, breasts with indeterminate x-ray mammography, and could also be used to accurately 3-dimensionally guide biopsy or surgical resection. Moreover, with the offset beam orientation, the transmission system is designed to have a variable FOV and minimize overall absorbed breast dose.

The invention relates to a micro-CT technology-based reservoir core three-dimensional entity model reconstruction method. The method includes the following steps that: a micro-CT technology is utilized to scan a reservoir core, so that a sectional scanning image of the reservoir core can be obtained, so that a CT image of a real reservoir core can be obtained, and a watershed algorithm is adopted to perform image segmentation on the CT image, so that the three-dimensional data of the image can be obtained; a Marching Cubes algorithm is adopted to generate a three-dimensional surface model of the reservoir core; and with the three-dimensional surface model of the reservoir core adopted as constraints, a constrained Delaunay tetrahedralization algorithm is utilized to generate the three-dimensional entity model of the reservoir core. According to the method of the invention, the three-dimensional entity model of the real reservoir core is established based on the sectional scanning image of the reservoir core, so that the obtained three-dimensional entity model of the reservoir core is more approximate to the structure of a real reservoir core. The method of the invention has the advantages of high accuracy and high efficiency. With the method adopted, defects of poor accuracy and low efficiency in the reconstruction of the three-dimensional entity model of a reservoir core in the prior art can be eliminated, and an effective guarantee can be provided for reservoir core simulation characteristic research.

A quantitative Single Photon Computed Emission Tomography (SPECT) reconstruction system for myocardial blood flow quantitation with SPECT or Single Photon Emission Computed Tomography/Computed Tomography (SPECT/CT) dynamic imaging. The present invention solves the problems of physical interference and patient motions in dynamic SPECT imaging to enable the quantitative ability for myocardial blood flow (MBF) and coronary flow reserve (CFR) quantification.

The invention provides a finite element modeling method for a human head for researching collision damage of an automobile. The finite element modeling method comprises the following steps: firstly, carrying out tomography and nuclear magnetic resonance scanning on the human head to obtain a tomography scanning image; secondly, importing the tomography scanning image into Mimics, and preprocessing the tomography scanning image to obtain point cloud data; thirdly, importing the point cloud data obtained in the second step into Geomagic Studio, and carrying out parameterized processing on the point cloud data to generate curved surfaces; detecting the generated curved surfaces, and fitting all the curved surfaces by using cubic Bezeir curves to obtain a three-dimensional geometrical model; fourthly, importing the three-dimensional geometrical model into HyperMesh for dividing meshes, setting the type of a unit body into a linear tetrahedral unit and optimizing local grids to obtain a three-dimensional solid model; fifthly, importing the three-dimensional solid model into Abaqus, defining characteristic parameters of tissue materials, and adding boundary and contact conditions for tissues to obtain a finite element model of the human head.

The present invention discloses a new non-destructive detection method for morphology and distribution of pores in welding seam. According to the method, a novel Nano-CT tomography system is adopted to detect a weldment, an X-ray source is adopted to carry out 360 DEG scanning on the welding component, a certain degree of attenuation can be generated when X rays penetrate through the weldment, energy attenuation of the X rays passing through the pores in a welding seam can be significantly lower than energy attenuation of the surrounding rays, a flat panel detector is adopted to receive transmission energies of different degrees of the attenuations so as to obtain multiple groups of tomography scanning images, and three-dimensional reconstruction is performed on the multiple groups of the tomography data to obtain a three-dimensional detection image of pore defect in the welding seam. The detection method has the following characteristics that: resolution is high, imaging is intuitive, the method is not affected by a weldment material type, a shape, a structure and other factors, important information such as a three-dimensional morphology, a pore size, a spatial distribution characteristic and the like of the pores in the welding seam can be obtained, and important significance is provided for pore classification, defect assessment and other aspects, wherein the important information such as a three-dimensional morphology, a pore size, a spatial distribution characteristic and the like is difficult obtained by using the conventional method.