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61.
Hannes Thielhelm Alexander Vais Daniel Brandes Franz-Erich Wolter 《The Visual computer》2012,28(6-8):529-539
In this paper, we present a novel method for computing multiple geodesic connections between two arbitrary points on a smooth surface. Our method is based on a homotopy approach that is able to capture the ambiguity of geodesic connections in the presence of positive Gaussian curvature that generates focal curves. Contrary to previous approaches, we exploit focal curves to gain theoretical insights on the number of connecting geodesics and a practical algorithm for collecting these. We consider our method as a contribution to the contemporary debate regarding the calculation of distances in general situations, applying continuous concepts of classical differential geometry which are not immediately transferable in purely discrete settings. 相似文献
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Gross Jürgen Peter Malzbender Jürgen Schwaiger Ruth 《Journal of Materials Science》2022,57(15):7481-7490
Journal of Materials Science - The application of ceramics in advanced functional applications often requires thicknesses below a few hundred micrometers, rendering an assessment of the... 相似文献
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We investigate deformation and failure of Al 6061-T6 in plane strain conditions through in situ scanning electron microscopy. The global behavior of the specimen, as well as the local deformation of the matrix material, second phase particles, and preexisting voids, is observed with a combination of high temporal/low spatial resolution images and low temporal/high spatial resolution images. It is found that the matrix dominates the deformation response, with the second phase particles and voids imparting little influence on the deformation under the moderate triaxiality levels encountered in this experiment. The initiation or nucleation of cracks is observed to occur by plastic slip. 相似文献
67.
ABSTRACTThe cleaning behavior of a soil with physical properties that depend on the wetting time is studied experimentally via the local phosphorescence detection method and simulated numerically in fully developed plane channel flow for Reynolds numbers up to 30,000. A computationally inexpensive general cleaning model is proposed, adopting an existing removal model and coupling it to the turbulent flow field. The influence of the soil on the flow is neglected and the transient behavior of the soil during cleaning is modeled in the form of a transient Dirichlet boundary condition. This approach is innovative for computational fluid dynamics of this phenomenon. The way of determining the model parameters from the experiment is described. The comparison of the simulation results with experimental data reveals very good suitability of the model in the case of a starch soil. A similar good agreement is found for data for a model protein foulant in tube flow from the literature. 相似文献
68.
Daniel Kleine Manfred Mürtz Jörg Lauterbach Hannes Dahnke Wolfgang Urban Peter Hering Karl Kleinermanns 《Israel journal of chemistry》2001,41(2):111-116
Cavity ring-down spectroscopy (CRDS) is a highly sensitive laser absorption method. It can be used for quantitative analysis of molecular species at the sub-ppb level. The absorption cell (cavity) is sealed by two high-reflective mirrors on each side, which results in an effective absorption path-length of some kilometers. Our experiments for atmospheric gas analysis have been carried out so far with an Excimer pumped dye laser in the UV-VIS and a CO overtone sideband laser in the wavelength region around 3 μm. Experiments with an all solid-state difference frequency laser system will follow. In the UV-VIS region, we measured trace gas molecules like SO2, NO2, and CH2O. In the mid-infrared, around 3 μm, we measured hydrocarbons like CH4, C2H6, and C2H4 with a detection limit of less than 1 ppb. The noise equivalent absorption coefficients in the MIR are in the order of 1.7·10−9 cm−1. Due to the high data acquisition rate and the high sensitivity, CRDS enables real-time detection of trace gases in ambient air. 相似文献
69.
Srivastava Sanjay; Tamir Maya; McGonigal Kelly M.; John Oliver P.; Gross James J. 《Canadian Metallurgical Quarterly》2009,96(4):883
There is growing interest in understanding how emotion regulation affects adaptation. The present study examined expressive suppression (which involves inhibiting the overt expression of emotion) and how it affects a critical domain of adaptation, social functioning. This investigation focused on the transition to college, a time that presents a variety of emotional and social challenges. Analyses focused on 2 components of suppression: a stable component, representing individual differences expressed both before and after the transition, and a dynamic component, representing variance specific to the new college context. Both components of suppression predicted lower social support, less closeness to others, and lower social satisfaction. These findings were robustly corroborated across weekly experience reports, self-reports, and peer reports and are consistent with a theoretical framework that defines emotion regulation as a dynamic process shaped by both stable person factors and environmental demands. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
70.
Miguel A. Otaduy Rasmus Tamstorf Denis Steinemann Markus Gross 《Computer Graphics Forum》2009,28(2):559-568
We present an algorithm for robust and efficient contact handling of deformable objects. By being aware of the internal dynamics of the colliding objects, our algorithm provides smooth rolling and sliding, stable stacking, robust impact handling, and seamless coupling of heterogeneous objects, all in a unified manner. We achieve dynamicsawareness through a constrained dynamics formulation with implicit complementarity constraints, and we present two major contributions that enable an efficient solution of the constrained dynamics problem: a time stepping algorithm that robustly ensures non-penetration and progressively refines the formulation of constrained dynamics, and a new solver for large mixed linear complementarity problems, based on iterative constraint anticipation. We show the application of our algorithm in challenging scenarios such as multi-layered cloth moving at high velocities, or colliding deformable solids simulated with large time steps. 相似文献