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951.
    
A robotic laser welding cell for stainless steel components, which includes a Cartesian robot, is described. The solution allows a drastic reduction in production times along with increased final quality compared to traditional welding technology, thus representing a particularly significant example of the advantages of the flexibility of a robot and the quality of the laser.  相似文献   
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This paper presents a meshless method for the modeling of shell‐type structures in fast dynamics. The model is based on the Mindlin–Reissner theory and takes into account material and geometric nonlinearities. The phenomena that occur prior to rupture are dealt with using damage laws, while the rupture itself is represented through the introduction of sharp discontinuities. The method does not represent cracks explicitly, which makes the treatment of multicracking easier. The time discretization is carried out in the framework of explicit dynamics, and the spatial discretization is handled through the smoothed particles hydrodynamics method and the use of moving least square functions. The capabilities of the method are demonstrated using cracking, puncturing and fragmentation examples. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
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A PCR test based on insertion sequence IS1081 was developed to detect Mycobacterium tuberculosis complex organisms in the peripheral blood. The method was applied to blood samples from immunocompetent individuals with localized pulmonary tuberculosis. Seven of 16 (43.75%) blood samples were found to be positive for the circulating DNA copies of M. tuberculosis complex.  相似文献   
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When 3D images are matched by using the immovable point method, the problem of detecting the straight lines in the binary 3D image that consists of points suspicious for immobility occurs. True immovable points are a thin approximately straight line being among the chaotically dispensing points. False straight line trajectories, which are parallel to the true one, are also possible. In this work a procedure for searching all straight lines in 3D binary images and detecting the true trajectory among them is described.  相似文献   
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The discussed challenge and its prospects in mining geoinformation science are connected with Big Data concept—flows of large sets of various data on mining. The authors describe Big Data technology and its general implementation on mini-clusters using Hadoop and MapReduce with case studies presented.  相似文献   
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A system for detecting X-ray shadowgraphs with a high spatial resolution, in which a shadowgraph formed on a luminophor is transferred to a charge-coupled device (CCD) matrix by using an objective lens, is considered. The signal stored on the CCD matrix is read, converted, and transmitted to the computer for further processing and representation. A 25-lp/mm spatial resolution was obtained for a 10.8 × 10.8-mm input field of the system. The measurements were performed by using a tungsten-wire standard placed on the surface of the input field of the detecting system, when the anode voltage was 45 kV, the anode current was ~2 mA, and the focal distance was 450 mm. It was shown that the 25-lp/mm spatial resolution is not limiting and that it is possible to attain a value of 40 lp/mm or higher.  相似文献   
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