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Geo-Spatial Database Management. Arnab Bhattacharya 5 th November, 2011. Ganga River Basin Management. Multiple themes Necessary to have interaction among thematic groups Certain types of knowledge possible only through interaction
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Geo-Spatial Database Management Arnab Bhattacharya 5th November, 2011
Ganga River Basin Management • Multiple themes • Necessary to have interaction among thematic groups • Certain types of knowledge possible only through interaction • Do number of dolphins decrease significantly when there are more tourists in a certain area? • Data sharing is the key • Knowledge extraction built on top • Thus, the geo-spatial database management (GDM) group
Functions of GDM • Central to the entire project • Data storage • Data sharing • Interchange of data format • Searching • Querying • Visualization • Repeatability • Security • Access control • Knowledge extraction
Data Storage • Database server • Upload/download facilities • Web frontend • www.gangalaya.in • www.gangagyan.in • Using open source software in Linux • ArcGISenabled
Searching and Querying • Using metadata tags • Find population of Kolkata in 2011 • How much rainfall happened in Kanpur in June? • Can be more complicated • Find all cities in Uttar Pradesh and Bihar that were flooded within 7 days of each other • Can be visual as well • Select a region and a time-period • Show attributes in that spatio-temporal data • Unit of data is spatio-temporal • Other attributes are values
Spatio-temporal Data • Spatial data • Point • Polygon/bounded space • Curve • Area/volume • Temporal data • Time point • Time interval • Spatio-temporal data • Any combination of spatial and temporal data
Visualization • Data is essentially geographic (GIS) • Mostly in forms of maps • Raster images • Vector images • Ability to register maps • Using geographic coordinates • Should be able to download final maps as images • Maintained at http://www.gise.cse.iitb.ac.in/GangaGeoportal/html/grbmp_gise.html
Security and Access Control • Who should be able to access which data? • Three types of users • Common user • GRBMP members • GRBMP thematic group leaders • Three types of access • Existence • Viewing • Downloading • Higher access type implies lower types • Downloading enables viewing, etc.
Access for Data • For each piece of data, there is essentially a vector of access control • Each element is for a particular user • Value determines the highest access • Whole access control is thus a matrix
Users and Groups • Users can be grouped • Thematic groups specify one type of groups • A user can create her own group • Access control rights for a data can be defined for a group
Status • Work in progress • Website is up • Basic upload/download facilities • Access control is being implemented • Visualization and querying facilities are provided Thank you!