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41.
Ioannis Bagkeris Vipin Michael Robert Prosser Adam Kowalski 《American Institute of Chemical Engineers》2021,67(7):e17201
The assumption of homogeneous isotropic turbulence when modeling drop breakage in industrially relevant geometries is questionable. We describe the development of an anisotropic breakage model, where the anisotropy is introduced via the inclusion of a perturbed turbulence spectrum. The selection of the perturbed spectrum is itself motivated by our previous large-eddy simulations of high-pressure homogenizers. The model redistributes energy from small to large scales, and assumes that the anisotropic part of the Reynolds stresses is confined to the energy-containing range. The second-order structure function arising from the perturbed spectrum is used in the standard framework of Coulaloglou and Tavlarides to calculate breakage frequency. While the base model exhibits non-monotonic behavior (by predicting a maximum value for a certain drop size), the effect of anisotropy is shown to increase breakage frequency in length scales larger than this peak, thereby reducing non-monotonicity. This effect is more pronounced for small turbulence Reynolds numbers. 相似文献
42.
D. L. Zhang Z. H. Cai G. Adam 《JOM Journal of the Minerals, Metals and Materials Society》2004,56(2):53-56
The processing of Al/TiO2 composite powders produced by high-energy mechanical milling leads to production of a range of valuable, titanium-based materials.
They include Ti(Al,O)/Al2O3 and TixAly(O)/Al2O3 composite powders, bulk composites and Ti3Al/TiAl alloy powders, and corresponding bulk materials. The strength of the Ti(Al,O)/Al2O3 and TixAly(O)/Al2O3 composites is moderate, but their high-temperature oxidation resistance is exceptionally high, making the titanium-based
composite powders favorable feedstock materials for protective coatings. The hardness of the Ti(Al,O)/Al2O3 and Ti3Al(O)/Al2O3 composites is also very high (10–16 GPa).
For more information, contact D.L. Zhang, University of Waikato, Waikato Centre for Advanced Materials, Department of Materials
and Process Engineering, Private Bag 3105, Hamilton, New Zealand; 011-64-7-838-4783; fax 011-64-7-838-4835; e-mail d.zhang@waikato.ac.nz. 相似文献
43.
In this paper, basic relationships and algorithms for numerical simulation of non-linear, self-excited vibrations in single degree-of-freedom cutting systems are presented. Non-linearities due to the tool leaving the cut, as well as interference between the cutting tool clearance face and cutting surface waviness, were taken into consideration. Examples of vibration simulation results are shown. 相似文献
44.
In this article I argue for rule-based, non-monotonic theories of common law judicial reasoning and improve upon one such theory offered by Horty and Bench-Capon. The improvements reveal some of the interconnections between formal theories of judicial reasoning and traditional issues within jurisprudence regarding the notions of the ratio decidendi and obiter dicta. Though I do not purport to resolve the long-standing jurisprudential issues here, it is beneficial for theorists both of legal philosophy and formalizing legal reasoning to see where the two projects interact. 相似文献
45.
Anuja Hariharan Marc Thomas Philipp Adam Timm Teubner Christof Weinhardt 《Electronic Markets》2016,26(4):339-355
Environmental conditions and the interplay of cognitive and affective processes both exert influences on bidding behavior. This paper brings the above together, considering how the (external) auction environment determines the impact of (internal) cognitive and affective processes on bidding behavior, assessed in comparison to the optimal bid. Two aspects of the auction environment were considered, namely auction dynamics (low: first-price sealed-bid auction, high: Dutch auction) and value uncertainty (low, high). In a laboratory experiment, we assess bidders’ cognitive workload and emotional arousal through physiological measurements. We find that higher auction dynamics increase the impact of emotional arousal on bid deviations, but not that of cognitive workload. Higher value uncertainty, conversely, increases the impact of cognitive workload on bid deviations, but not that of emotional arousal. Taken together, the auction environment is a critical factor in understanding the nature of the underlying decision process and its impact on bids. 相似文献
46.
In this work, we present a method of decomposition of arbitrary unitary matrix \(U\in \mathbf {U}(2^k)\) into a product of single-qubit negator and controlled-\(\sqrt{\text{ NOT }}\) gates. Since the product results with negator matrix, which can be treated as complex analogue of bistochastic matrix, our method can be seen as complex analogue of Sinkhorn–Knopp algorithm, where diagonal matrices are replaced by adding and removing an one-qubit ancilla. The decomposition can be found constructively, and resulting circuit consists of \(O(4^k)\) entangling gates, which is proved to be optimal. An example of such transformation is presented. 相似文献
47.
In Face on Facebook: Brooklyn's Drag Community and Sociotechnical Practices of Online Communication
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Recently, Brooklyn has seen an explosion of drag culture, with dozens of performers taking the stage in any given week. Social media plays a vital role for members of this community, simultaneously allowing self‐promotion and community solidarity. Drawing on focus group interviews, we analyze the communication practices of Brooklyn's drag performers, examining both the advantages and drawbacks of social media platforms. Using conceptual frameworks of faceted identity and relational labor, our discussion focuses on affordances and constraints of multifaceted identity in online contexts and theories of seamful design. We contend that by analyzing online communication practices of drag performers, it becomes possible to identify gaps between embedded ideologies of mainstream social media technologies and the localized values of outsider communities. 相似文献
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50.
Adam Klimanek 《Archives of Computational Methods in Engineering》2013,20(1):61-109
Numerical modelling of natural draft wet-cooling towers is considered in this paper. Development of a complete CFD model capable of predicting cooling tower performance under various operating conditions is presented. A step-by-step approach is employed, thus one-dimensional numerical modelling of counterflow heat and mass exchangers is extensively presented first. This is followed by reduced order modelling of heat and mass transfer in cooling tower fills by means of proper orthogonal decomposition radial basis function networks. Then the approaches in modelling of droplet zones (rain and spray zones) are discussed. Finally the two and three-dimensional CFD models are discussed. 相似文献