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Free and Open Source Software for Geospatial (FOSS4G) Conference Proceedings
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Supporting Trajectory Udf Queries And Indexes On Postgis, Pyoung Woo Yang, Kwang Woo Nam
Supporting Trajectory Udf Queries And Indexes On Postgis, Pyoung Woo Yang, Kwang Woo Nam
Free and Open Source Software for Geospatial (FOSS4G) Conference Proceedings
In this paper, we propose a system model for querying and indexing the GPS trajectory of moving objects on PostGIS/PostgreSQL. We developed moving object data types including MPoint(moving point), MDouble(moving double) for GPS trajectories. Also, various moving objects UDFs(user-defined functions) are implemented for moving objects queries. For efficient query processing, r-tree index is extended for trajectory, and pre-materialization techniques are proposed for fast UDF processing. Experimental results show that the pre-materialization techniques are about 1.2 times faster than naïve query processing using r-tree index.
Gis Investigation Of Crime Prediction With An Operationalized Tweet Corpus, Anthony J. Corso, Abdulkareem Alsudais
Gis Investigation Of Crime Prediction With An Operationalized Tweet Corpus, Anthony J. Corso, Abdulkareem Alsudais
Free and Open Source Software for Geospatial (FOSS4G) Conference Proceedings
Social media as the de facto communication channel is being used to disseminate one’s diurnal self-revelations. This profound discovery often contains double-talk, peculiar insights, or contextual information about real-world events. Natural language processing is regularly used to uncover both obvious and latent knowledge claims within disclosures published amid the complex environment. For example, a perpetrator with first-hand knowledge of their criminal incident uses social media to post critical information about it. A geographic information system (GIS) is capable of large-scale point data analysis and possesses methods that enable dataset processing, evaluation, and automatic spatial visualization. Such an artifact—fused with traditional …
Qkan - Management Of Drainage System Data With Qgis, Jörg Höttges
Qkan - Management Of Drainage System Data With Qgis, Jörg Höttges
Free and Open Source Software for Geospatial (FOSS4G) Conference Proceedings
Based on QGIS a database structure and a set of plugins have been developed to improve the workflow for the hydraulic design of urban drainage systems for consulting engineers. The main goal is pre- and postprocessing in combination with various commercial hydraulic simulation software packages. The plugins provide import and export functionalities, simulation result viewing and generation of longitudinal cross sections in a CAD program. All modules make intensive use of SQL based spatial functions instead of functions implemented in QGIS, because of their stability, higher flexibility and speed due to the indexing functionality. On the other hand the database …
Analyzing The Performance Of Nosql Vs. Sql Databases For Spatial And Aggregate Queries, Sarthak Agarwal, Ks Rajan
Analyzing The Performance Of Nosql Vs. Sql Databases For Spatial And Aggregate Queries, Sarthak Agarwal, Ks Rajan
Free and Open Source Software for Geospatial (FOSS4G) Conference Proceedings
Relational databases have been around for a long time and spatial databases have exploited this feature for close to two decades. The recent past has seen the development of NoSQL non-relational databases, which are now being adopted for spatial object storage and handling, too. While SQL databases face scalability and agility challenges and fail to take the advantage of the cheap memory and processing power available these days, NoSQL databases can handle the rise in the data storage and frequency at which it is accessed and processed - which are essential features needed in geospatial scenarios, which do not deal …