Lattice Boltzmann models for diffusion equation are generally in Cartesian coordinate system. Very few researchers have attempted to solve diffusion equation in spherical coordinate system. In the lattice Boltzmann based diffusion model in spherical coordinate system extra term, which is due to variation of surface area along radial direction, is modeled as source term. In this study diffusion equation in spherical coordinate system is first converted to diffusion equation which is similar to that in Cartesian coordinate system by using proper variable. The diffusion equation is then solved using standard lattice Boltzmann method. The results obtained for the new variable are again converted to the actual variable. The numerical scheme is verified by comparing the results of the simulation study with analytical solution. A good agreement between the two results is established.
To deal with problems of traditional geographic information collection, such as low real-time, poor authenticity of the data, and unclear description of detailed areas, a design scheme of remote sensing-based geographic information system is proposed. The system mainly consists of information collection, imaging processing, data storage management, scene control and data transmission module. By use of remote sensing technology, the reflected and radiated electromagnetic waves of the target area are collected from a long distance to form an image, and the hue–intensity–saturation (HIS) transformation method is used to enhance the image definition. Weighted fusion algorithm is adopted to process the details of the image. The spatial database stores and manages the text and image data respectively, and establishes the attribute self-correlation mechanism to render the ground objects in the picture with SketchUp software. Finally, using RS422 protocol to transmit information can achieve the effect of multi-purpose, and enhance the anti-interference of the system. The experimental results show that the practical experience of the proposed system is excellent, the geographic information image presented is clear, and the edge details are clearly visible, which can provide users with effective geographic information data.
Today, diffusion-weighted MRI is an important, complementary sequence in an MRI of the abdomen, especially in oncological questions, but also in inflammatory diseases. The following paper deals with the technical basics and shows typical indications and findings as well as the value of the method in the diagnosis of parenchymatous upper abdominal organs and the gastrointestinal tract.
The integration of medical images is the process of registering and fusing them to obtain a greater amount of diagnostic information. In this work an analysis is performed for the integration of images obtained through computed axial tomography and magnetic resonance imaging, for which a tool was developed in the Matlab program, where the registration is implemented through equivalent features; in addition, the pairs of images are compared by several fusion rules, with a view to identify the best algorithm in which the resulting fused image contains the most information from the original representations.
Imaging technology plays a key role in guiding endovascular treatment of aortic aneurysm, especially in the complex thoracoabdominal aorta. The combination of high quality images with a sterile and functional environment in the surgical suite can reduce contrast and radiation exposure for both patient and operator, in addition to better outcomes. This presentation aims to describe the current use of this technique, combining angiotomography and intraoperative cone beam computed tomography, image “fusion” and intravascular ultrasound, to guide procedures and thus improve the intraoperative success rate and reduce the need for reoperation. On the other hand, a procedure is described to create customized 3D templates with the high-definition images of the patient’s arterial anatomy, which serve as specific guides for making fenestrated stents in the operating room. These customized fenestration templates could expand the number of patients with complex aneurysms treated minimally invasively.
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