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71.
Metallurgical and Materials Transactions A - The effects of hot deformation on the bainitic transformation of a low carbon steel during continuous cooling were comprehensively studied through in...  相似文献   
72.
Plant growth visualization from a series of 3D scanner measurements is a challenging task. Time intervals between successive measurements are typically too large to allow a smooth animation of the growth process. Therefore, obtaining a smooth animation of the plant growth process requires a temporal upsampling of the point cloud sequence in order to obtain approximations of the intermediate states between successive measurements. Additionally, there are suddenly arising structural changes due to the occurrence of new plant parts such as new branches or leaves. We present a novel method that addresses these challenges via semantic segmentation and the generation of a segment hierarchy per scan, the matching of the hierarchical representations of successive scans and the segment-wise computation of optimal transport. The transport problems' solutions yield the information required for a realistic temporal upsampling, which is generated in real time. Thereby, our method does not require shape templates, good correspondences or huge databases of examples. Newly grown and decayed parts of the plant are detected as unmatched segments and are handled by identifying corresponding bifurcation points and introducing virtual segments in the previous, respectively successive time step. Our method allows the generation of realistic upsampled growth animations with moderate computational effort.  相似文献   
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Hyperspectral imaging sensors have been introduced for measuring the health status of plants. Recently, they also have been used for close-range sensing of plant canopies with a highly complex architecture. However, the complex geometry of plants and their interaction with the illumination setting severely affect the spectral information obtained. Furthermore, the spatial component of analysis results gain in importance as higher plants are represented by multiple plant organs as leaves, stems and seed pods. The combination of hyperspectral images and 3D point clouds is a promising approach to face these problems. We present the generation and application of hyperspectral 3D plant models as a new, interesting application field for computer vision with a variety of challenging tasks. We sum up a geometric calibration method for hyperspectral pushbroom cameras using a reference object for the combination of spectral and spatial information. Furthermore, we show exemplarily new calibration and analysis methods enabled by the hyperspectral 3D models in an experiment with sugar beet plants. An improved normalization, a comparison of image and 3D analysis and the density estimation of infected surface points underline some of the new capabilities gained using this new data type. Based on such hyperspectral 3D models the effects of plant geometry and sensor configuration can be quantified and modeled. In future, reflectance models can be used to remove or weaken the geometry-related effects in hyperspectral images and, therefore, have the potential to improve automated plant phenotyping significantly.  相似文献   
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Patients with inflammatory bowel disease (IBD) are known to have increased antibodies to several food and bacterial antigens. To assess selected isotype contributions in greater detail, we examined the concentrations of IgA, IgG, IgE, and IgG4 antibodies to five selected antigens, two of bacterial and three of food origin. Thirty patients with IBD and thirty matched healthy controls were studied. Most antibodies were increased in IBD patients compared to controls. Statistically significant increases were more frequent in Crohn's disease (CD) than in ulcerative colitis (UC). An unexpected finding was that IBD patients treated with sulfasalazine had statistically higher levels of most IgA antibodies than healthy controls, while steroid treated patients had lower levels. These findings suggest differing effects on the immune systems of IBD patients by each of these commonly used drugs.  相似文献   
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Messung der Gitterebenenabstände an der (211)-lnterferenz bei Raumtemperatur und 300°C an Zugproben der Stähle 15 Mo 3, 13 CrMo 44 und 34 CrMo 4. Ermittlung der Eigenspannungen, der thermischen Ausdehnungskoeffizienten und der röntgenographischen Elastizitätskonstanten. 1/2 s2 (211) hat bei 300°C einen um rd. 20% kleineren Wert als bei Raumtemperatur. Die Ursache des Abfalls wird diskutiert.  相似文献   
79.
The safety of early vacuum aspiration performed as an outpatient procedure using local anesthesia was examined in a controlled study sponsored by the World Health Organization and undertaken in two centers in Yugoslavia and Singapore. The sample consisted of healthy women whose pregnancies were between 7 and 12 weeks in duration. Follow-up four weeks after abortion was nearly 100 percent in both centers. No important differences in complication rates were found between the different types of services and anesthesia, even though overall complication rates differed markedly between centers. Overnight postabortion observation was not associated with any decrease in complications.  相似文献   
80.
The different assumptions made by discrete and componential emotion theories about the nature of the facial expression of emotion and the underlying mechanisms are reviewed. Explicit and implicit predictions are derived from each model. It is argued that experimental expression-production paradigms rather than recognition studies are required to critically test these differential predictions. Data from a large-scale actor portrayal study are reported to demonstrate the utility of this approach. The frequencies with which 12 professional actors use major facial muscle actions individually and in combination to express 14 major emotions show little evidence for emotion-specific prototypical affect programs. Rather, the results encourage empirical investigation of componential emotion model predictions of dynamic configurations of appraisal-driven adaptive facial actions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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