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Mitchell for comments on the dissertation proposal; Henry L. Roediger III and Suparna Rajaram for comments on the article; and Branch Coslett for advice on creating the usual and unusual views. I would also like to thank J. Kroll, D. L. Schacter, E. Hirshman, and an anonymous reviewer for their insightful reviews.

Efficient storage and querying of RDF data is of increasing importance, due to the increased popularity and widespread acceptance of RDF on the web and in the enterprise. In this paper, we describe a novel storage and query mechanism for RDF which works on top of existing relational representations. Reliance on relational representations of RDF means that one can take advantage of 35+ years of research on efficient storage and querying, industrial-strength transaction support, locking, security, etc. However, there are significant challenges in storing RDF in relational, which include data sparsity and schema variability. We describe novel mechanisms to shred RDF into relational, and novel query translation techniques to maximize the advantages of this shredded representation. We show that these mechanisms result in consistently good performance across multiple RDF benchmarks, even when compared with current state-of-the-art stores. This work provides the basis for RDF support in DB2 v.10.1.

The effects of rotating familiar and novel objects in depth between study and test were explored on short-term recognition, long-term recognition, and priming tasks. Short-term recognition memory was not affected by rotation in depth when the study and test views shared the same visible parts. However, long-term recognition was sensitive to rotation, even when all the parts were visible in both views. Priming was also affected by rotation, but only when study and test views did not share the same parts, or when test views were generated from rotations greater than 67 degrees. Together, the results suggest that long-term recognition memory is mediated by representations that specify viewpoint in depth precisely, whereas priming is mediated by representations that are more broadly tuned with respect to orientation. Furthermore, the insensitivity of the short-term recognition memory task to rotation suggests the possibility that viewpoint-invariant descriptions are generated from multiple successive views.

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