http://dspace.infodocu.lbd.org.es/xmlui/handle/123456789/1413 Conferencias relacionado con estructura de datos 2026-05-22T19:04:50Z http://dspace.infodocu.lbd.org.es/xmlui/handle/123456789/1416 Efficient Compression and Indexing of Trajectories R. Brisaboa, Nieves; Gagie, Travis; Gómez-Brandón, Adrián; Navarro, Gonzalo; R. Paramá, José We present a new compressed representation of free trajectories of moving objects. It combines a partial-sums-based structure that retrieves in constant time the position of the object at any instant, with a hierarchical minimum-bounding-boxes representation that allows determining if the object is seen in a certain rectangular area during a time period. Combined with spatial snapshots at regular intervals, the representation is shown to outperform classical ones by orders of magnitude in space, and also to outperform previous compressed representations in time performance, when using the same amount of space. 2014-01-01T00:00:00Z http://dspace.infodocu.lbd.org.es/xmlui/handle/123456789/1414 Efficient set operations over k2-trees R.Brisaboa, Nieves; de Bernardo, Guillermo; Gutiérrez, Gilberto; Ladra, Susana; R. Penabad, Miguel; A. Troncoso, Brunny k2-trees have been proved successful to represent in a very compact way differentkinds of binary relations, such as web graphs, RDFs or raster data. In order to be afully functional succinct representation for these domains, thek2-tree must support all therequired operations for binary relations. In their original description, the authors includehow to answer some of the most relevant queries over thek2-tree. In this paper, we extendthis functionality and detail the algorithms to efficiently compute thek2-tree resulting fromthe union, intersection, difference or complement of binary relations represented usingk2-trees. 2015-01-01T00:00:00Z