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We investigate runtime strategies for data-intensive applications that involve generalized reductions on large, distributed datasets. Our set of strategies includes replicated filter state, partitioned filter state, and hybrid options between these two extremes. We evaluate these strategies using emulators of three real applications, different query and output sizes, and a number of configurations. We consider execution in a homogeneous cluster and in a distributed environment where only a subset of nodes host the data. Our results show replicating the filter state scales well and outperforms other schemes, if sufficient memory is available and sufficient computation is involved to offset the cost of global merge step. In other cases, hybrid is usually the best. Moreover, in almost all cases, the performance of the hybrid strategy is quite close to the best strategy. Thus, we believe that hybrid is an attractive approach when the relative performance of different schemes cannot be predicted.

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Currently, fabrication of composite materials is of great interest in industry. By combining materials of different properties, we can produce new composite materials with synergetic functionality that individual materials do not possess. In this study, Al2O3 nanosized particles were coated on Al2O3 fiber substrates using a dry mechanical coating technique employing high shear and compression forces. The materials thus synthesized had high surface area with good dispersion for enhanced reactivity and were strong to sustain rigorous operation. Operating parameters, including rotor speed, processing time and initial loading percentage were varied to study their effects on the coating condition. The experimental results showed that the product surface area increased as the nanoparticle loading increased. The dispersion of nanoparticles improved as the processing time increased. A higher rotor speed resulted in a shorter product length while the nanoparticle loading had no effect on the product length. The durability test, conducted in a fluidized bed, indicated no significant change of the coating layer after 7 days of continuous testing.

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