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With the increasing availability of locating and navigation technologies on portable wireless devices, huge amounts of location data are being captured at ever growing rates. Spatial and temporal aggregations in an Online Analytical Processing (OLAP) setting for the large-scale ubiquitous urban sensing data play an important role in understanding urban(More)
Motivated by the practical needs for efficiently processing large-scale taxi trip data, we have developed techniques for high performance online spatial, temporal and spatiotemporal aggregations. These techniques include timestamp compression to reduce memory footprint, simple linear data structures for efficient in-memory scans and utilization of massively(More)
Geospatial analyses of distributed data from surveys and sensors are often stored and managed in diverse regional , national and global repositories. The nature of scientific processes requires composition of these resources in a meaningful order to solve a specific geoscience problem. These tasks can be viewed as scientific workflows. Web based interfaces(More)
Cluster computing, Cloud computing and GPU computing play overlapping and complementary roles in parallel processing of geospatial data within the general HPC framework. The fast increasing hardware capacities of modern personal computers equipped with chip multiprocessor CPUs and massively parallel GPUs have made high performance computing of large-scale(More)
Normalized difference vegetation index (NDVI) Beta diversity Bray–Cutis dissimilarity index Taxonomic rank Ecoregion Phenology Mantel test a b s t r a c t Finding an effective method to quantify species compositional changes in time and space has been an important task for ecologists and biogeographers. Recently, exploring regional floristic patterns using(More)
a r t i c l e i n f o Keywords: Beta diversity MODIS NDVI Mantel test Multivariate distance WWF ecoregion Biogeographical Evolutionary history Considerable amount of research on the relationships between species diversity and productivity at different spatial, ecological, and taxonomic scales has been conducted. However, the overall trend of the correlation(More)
Biodiversity and ecosystem data are both geo-referenced and " species-referenced ". Ecoregion classification systems are relevant to basic ecological research and have been increasingly used for making policy and management decisions. There are practical needs to integrate taxonomic data with ecoregion data in a GIS to visualize and explore species(More)