Department of Computer Science Federal University of São Carlos São Carlos SP, Brazil

Transcription

1 Department of Computer Science Federal University of São Carlos São Carlos SP, Brazil 12th International Conference on Enterprise 50 Information Systems ICEIS 2010 /

2 Outline Motivations and Goals Multidimensional Analysis Environments (Geographic) Data Warehouse and (Spatial) OLAP Geovisualization in GDW/SOLAP Tools Virtual Globes and Thematic Maps The GlobeOLAP Prototype Architecture Study Case Demonstration Discussion Advantages and issues References 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

3 Motivations The WebPIDE Project (CAPES/INEP grant) challenges: Extracting, integrating and visualizing many gigabytes of data from national educational evaluations Multidimensional data Geospatial and temporal data Need for user-friendly solution Limitations in geovisualization modules of multidimensional analysis tools 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

4 Goals of this paper Investigate the introduction of two functionalities in multidimensional analysis tools: Virtual globes (e.g. Google Earth) Custom thematic maps Discuss advantages and potential issues Propose an architecture 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

5 Data Warehouse and OLAP Widely used for decision support Priotize efficient querying of huge amounts of integrated and historical data Mutidimensional modeling Star Schema Attribute hierarquies Dimensions Facts Redundancy! Measures 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

6 Data Warehouse and OLAP 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

7 Data Warehouse and OLAP + JPivot 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

8 Geographic Data Warehouse and Spatial OLAP Allows a geospatial perspective in multidimensional analysis Georreferenced geometries are maitained in one or more dimensions, or at least in one measure. 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

9 Geovisualization in GDW/SOLAP tools Geobrowsers It can be seen as the Geographic Information System (GIS) visualization module Results from multidimensional queries in maps 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

10 2D Geobrowsers Existing 2D geobrowsers: Google Maps API Bing Maps API Yahoo! Maps Web Services ESRI ArcGIS Online / WebMapping API OpenLayers API Functionalities: pan, zoom, layer control, descriptions of features, geospatial web services (geocoding, route calculation, local search). Two main types of images: street/boundaries maps and remote sensing images 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

11 3D Geobrowsers: Virtual Globes Existing Virtual Globes: Google Earth NASA World Wind Marble Skyline Global Three-dimensional model of the Earth surface The same tiles from 2D Geobrowsers, but now with an orientation angle of Perspective Ortographic projection. Camera controlling inclination and rotation of the view 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

12 Thematic Maps Main type of map for analysis of summarized and contextualized (both geographically and thematically) data Representation of the spatial distribution of phenomena at specific points in time GDW/SOLAP and Thematic Maps convergence: Every dimension or measure can be seen as a theme Data aggregation by (S)OLAP operatiors goes toward a theme refining Thematic Maps can be an efficient geospatial and analytical summary of data from a GDW 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

13 Related works Rivet from Stolte et al. (2002) June 10, th International Conference on Enterprise Information Systems ICEIS / 50

14 Related works SOVAT from Scotch and Parmanto (2005) June 10, th International Conference on Enterprise Information Systems ICEIS / 50

15 Related works Jmap Spatial OLAP Extension from Rivest et al. (2005) June 10, th International Conference on Enterprise Information Systems ICEIS / 50

16 Related works OLAP for ArcGIS, ESRI June 10, th International Conference on Enterprise Information Systems ICEIS / 50

17 Related works JPivot showing tabular data Map View Bimonte et al. (2007) June 10, th International Conference on Enterprise Information Systems ICEIS / 50

18 Related works Di Martino et al. (2009) June 10, th International Conference on Enterprise Information Systems ICEIS / 50

19 Related works June 10, th International Conference on Enterprise Information Systems ICEIS / 50

20 GlobeOLAP prototype Combining Virtual Globes and Thematic Maps technologies in GDW/SOLAP environments! Architecture 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

21 Study Case Goal of the study case: Investigate the feasibility of integrating Virtual Globes + 3D Thematic Maps + GDW/SOLAP environments Materials: Raw data from national evaluations, applied on brazilian students by the government ministry of education ONTOPTool (Hernandes, 2010), for cleaning data PostgreSQL PostGIS 1.4, as our database DEAR tool (Siqueira, 2008), for loading data into PostgreSQL Pentaho Mondrian JPivot, as OLAP server and Pivot Table Java Tomcat 6.0, as platform for Mondrian Schema Workbench 3.2, for generating XML schemas for the GDW Google Earth API, as our Virtual Globe Thematic Map Engine 1.6 (Sandvik, 2008), as our map generator 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

22 Study Case We choose to start with data from SAEB (Evaluation System for Basic Education) 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

23 Study Case By slicing Test Year=2003, choosing Localization as column and Avg Proficiency as a measure, we can answer the following question: Which are proficiency average the students have in each state in 2003? 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

24 Study Case 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

25 Study Case 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

26 Demonstration 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

27 Discussion Advantages of Virtual Globes + GDW Richer environment, more details More space for information Provides a familiar environment for complex analysis Reduce area distortions Advantages of Thematic Maps + GDW Efficient geospatial and analytical summary of data from a GDW Thematic maps can be overlayed for multidimensional analysis Advantages of the third dimension in Thematic Maps Emphasize and detail a bi-dimensional visual variable [Slocum, 2005; Sandvik, 2008; Shepherd, 2008; Tiede and Lang, 2010] 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

28 Discussion Potential issues Too many non-essential visual variables may produce a confusing map Dynamic scaling may prejudice human hability of estimating volumes Virtual globes usually demands more user interaction [Monmonier, 1996; Slocum, 2005; Goodchild, 2008; Shepherd, 2008] 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

29 Discussion Some partial solutions (future works) Allowing users to choose between 2D map or Virtual Globe Use of two side-by-side Virtual Globes Use of perspective control in non-globe 3D maps [Monmonier, 1996; Slocum, 2005; Goodchild, 2008; Shepherd, 2008] 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

30 Discussion It is possible to use three-dimensional Thematic Maps and Virtual Globes for geovisualization of multidimensional queries 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15

31 References 20/05/ th International Conference on Enterprise Information Systems ICEIS / 15