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Multimedia Tools and Applications - The typical centralized cloud model is poorly suited to latency-sensitive applications requiring low-latency and high-throughput. This paper proposes an...  相似文献   
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Designing rotational symmetry fields on surfaces is an important task for a wide range of graphics applications. This work introduces a rigorous and practical approach for automatic N-RoSy field design on arbitrary surfaces with user-defined field topologies. The user has full control of the number, positions, and indexes of the singularities (as long as they are compatible with necessary global constraints), the turning numbers of the loops, and is able to edit the field interactively. We formulate N-RoSy field construction as designing a Riemannian metric such that the holonomy along any loop is compatible with the local symmetry of N-RoSy fields. We prove the compatibility condition using discrete parallel transport. The complexity of N-RoSy field design is caused by curvatures. In our work, we propose to simplify the Riemannian metric to make it flat almost everywhere. This approach greatly simplifies the process and improves the flexibility such that it can design N-RoSy fields with single singularity and mixed-RoSy fields. This approach can also be generalized to construct regular remeshing on surfaces. To demonstrate the effectiveness of our approach, we apply our design system to pen-and-ink sketching and geometry remeshing. Furthermore, based on our remeshing results with high global symmetry, we generate Celtic knots on surfaces directly.  相似文献   
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A clinker and a cement obtained from a raw mix containing ceramic waste as an alternative raw material were characterized in the present study. Their hydration, physical–chemical properties and leaching behaviour in different acid media were also explored. The findings showed that both the clinker and the cement met all the requirements set out in European standards EN 197-1 [1], although they had higher ZnO, ZrO2, and B2O3 contents than an industrially produced reference product.According to the hydration studies, initial hydration was somewhat retarded in the new cement, which exhibited longer initial and final setting times and lower 2-day mechanical strength. The SEM/BSE/EDS microstructural study showed, however, that morphologically and compositionally, the hydration products formed were comparable to unadditioned Portland cement paste products. While low concentrations of Zn and B were observed to leach in acid media, the biotoxicity trials conducted confirmed that these concentrations were not toxic. Zr was retained in the cement pastes.  相似文献   
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Phthalates are the most important plasticizers used in the polymer industry. However, their fossil origin and the results of recent tests showing their potential negative effect on human health have encouraged the polymer industry to turn toward non‐phthalate plasticizers. At the same time, the biodiesel industry produces a surplus of glycerol, thus leading the scientific community to seek new applications for this substance. This paper presents the performance of eight esters derived from glycerol as plasticizers for poly(vinyl chloride), including tests to evaluate their compatibility. Results show that glycerol esters obtained from propanoic, butanoic, isobutanoic, isopentanoic, and benzoic acids, while volatile, can be used as poly(vinyl chloride) plasticizers in certain applications. J. VINYL ADDIT. TECHNOL., 20:65–71, 2014. © 2014 Society of Plastics Engineers  相似文献   
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