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The Journal of Supercomputing - An optimal replacement policy that minimizes the miss rate in a private cache was proposed several decades ago. It requires knowing the future access sequence the...  相似文献   
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Herein, the design, synthesis, and characterization of bifunctional hybrid nanoreactors used for concurrent one‐pot chemoenzymatic reactions are shown. In the design, the enzyme, glucose oxidase, is wrapped with a peroxidase‐mimetic catalytic polymer. Hemin, the organic catalyst, is linked to the flexible polymeric scaffold through coordination to the imidazole groups that hang out the network. This spatial arrangement, which works as a metabolic channel, is optimized for cooperative chemoenzymatic reactions in which the enzyme catalyzes first. A deep characterization of the integrated nanoreactors demonstrates that the confinement of two distinct catalytic sites in the nanospace is very effective in one‐pot reactions. Moreover, besides its role as scaffold material, the polymeric mantel protects both the biocatalyst and the chemical catalyst from degradation and inactivation in the presence of organic solvents. Furthermore, the polymeric environment of the nanoreactors can be tailored in order to trigger the assembly of those into highly active heterogeneous hybrid catalysts. Finally, the new nanoreactors are applied to the efficient degradation of organic aromatic compounds using glucose as the only fuel.  相似文献   
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The development of inhibitors for hydrochloric acidic media is very common. Potassium iodide, in combination with some organic inhibitors, may transform a mediocre inhibitor into an excellent corrosion inhibitor based on a synergetic effect. There is a need to study what happens at the interface in the presence of this compound. The dynamics of the metal electrolyte interface when KI concentration increases has been characterized. The present study has been carried out based on electrochemical impedance spectroscopy and electrochemical noise analysis in the light of nonlinear phenomena by applying recurrence plots and fractal geometry. The fractal dimension of the current–time series shows a direct relationship with the fractal dimension of the surface of steel. The phenomenon of self-organization has been observed on the metal surface. The nonlinear analysis carried out by means of recurrence plots showed that the iodide ions' inhibitory effect is not only simple adsorption but also a nonlinear phenomenon that auto-organizes. The degree of complexity increases, consequently causing an interaction between the microcells and resulting in a lower charge-transfer rate.  相似文献   
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Information Systems and e-Business Management - Service providers compose services in service chains that require deep integration of core operational information systems across organizations....  相似文献   
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One important challenge in mathematics education is teaching modeling skills. We analyze the logs from a game-based learning system used in a massively multiplayer online tournament. Students had to detect an input–output pattern across 20 rounds. For each round, they received an input and had 2 minutes to predict the output by selecting a binary option (2 points if correct, ?1 otherwise), or writing a model (4 points if model prediction was correct, ?4 otherwise), or refraining (1 point). Thousands of 3rd to 10th grade students from hundreds of schools simultaneously played together on the web. We identified different types of players using cluster analysis. From 5th grade onwards, we found a cluster of students that wrote models with correct predictions. Half of the 7th to 10th grade students that detected patterns were able to express them with models. The analysis also shows diffusion within the teams of modeling strategies for simple patterns.  相似文献   
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We present a scalable solution to render complex scenes from a large amount of viewpoints. While previous approaches rely either on a scene or a view hierarchy to process multiple elements together, we make full use of both, enabling sublinear performance in terms of views and scene complexity. By concurrently traversing the hierarchies, we efficiently find shared information among views to amortize rendering costs. One example application is many‐light global illumination. Our solution accelerates shadow map generation for virtual point lights, whose number can now be raised to over a million while maintaining interactive rates.  相似文献   
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