Monica Scannapieco, Pasquale Testa – IT Unit on Information Systems for

Statistics

Pina Grazia Ticca, Sonia Scialanca – Geographic Information System Unit

Istat - Italy

An Enhanced Visualization Service

based on Geospatial and Statistical

Linked Open Data

Brussels, NTTS, 10-12 March 2015

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 2

Outline

Visualization of Geospatial Data

– Geographical Information Systems (GISs)

– Linked Geo Data

Illustration of possible scenarios with

implementation examples

Conclusions

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 3

Background: Geographical Information

Systems

Geographical Information

Systems (GISs) enabling

interactive visualization,

e.g.:

– Explore different layers of

maps

– Zoom in or out

– Change visual appearance

of maps

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 4

Background: LOD & Linked Geo Data

Family of Semantic Web standards to formal

model and query data on the Web

– Data Modelling: Resource Description

Framework (RDF), RDF Schema, Ontology Web

Language (OWL)

– Data Querying/ Information Discovery: SPARQL

(SPARQL Query Language for RDF)

GeoSPARQL - A Geographic Query

Language for RDF Data

– Modelling and querying of geospatial data

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 5

Scenario 1: Integrating Linked Open data

Platform and GIS

Visualization

Layer as part

of the GIS

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 6

Scenario 2: Querying of Linked Geo Data

Visualization

Layer as part

of the LOD

Portal

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 7

Implementing Scenario 1

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 8

Geospatial data published through

MapServices using Gistat platform

Geographical layers

available

Admin areas: Regions,

Provinces, Municipalities

Census entities: Localities,

Enumeration areas, sub-

urban areas

Basemaps and references

maps

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 9

Example 1: SPARQL results queried by Gistat

Selection of commuting

indicators (pendolarismo)

for all enumeration

areas of San Marcello

municipality of the region

Marche

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 10

Example 1: Visualization of the query result as a

thematic map

Filter the EAs

Thematic on a

statistic field

Display on top

of a reference

map

Sezioni2011 - Number of commuting pepole(enumeration areas)

2 - 15

16 - 33

34 - 56

57 - 117

118 - 234

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 11

Example 2: SPARQL results queried by Gistat

Selection of indicators

related to families

(Famiglie)

for all enumeration

areas of Terni

municipality of the region

Umbria

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 12

Example 2: Visualization of the query result as a

thematic map (one-person families -Terni)

Filter the EAs

Thematic on a

statistic field

Display on top

of a reference

map

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 13

Implementing Scenario 2

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 14

Implementation steps

Modelling geospatial concepts

Mapping geospatial concepts to data

Query specification / Visualization

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 15

Modelling Linked Geo Data

:Comune rdfs:subClassOf ogc:Feature .

:SezCens rdfs:subClassOf ogc:Feature .

:exactGeometry rdfs:subPropertyOf ogc:hasGeometry .

:Roma rdf:type :Comune .

:SezCens1 rdf:type :SezCens .

:SezCens1 :haPopolazioneResidente “123456"^^xsd:integer .

:SezCens1 :exactGeometry :geo1 .

:geo1 ogc:asWKT "Polygon((…))"^^ogc:wktLiteral .

:SezCens1 ogc:sfWithin :Roma .

:Roma :exactGeometry :geo2 .

:geo2 ogc:asWKT "Polygon((…))"^^ogc:wktLiteral .

Meta Information

Non-spatial Properties

Spatial Properties

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 16

Visualization: an example

Slippy Map refers to modern web maps which let

you zoom and pan around (the map slips around

when you drag the mouse)

LGD Browser and Editor:

http://browser.linkedgeodata.org/

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 17

Comparing the two scenarios

Visualization

and

Geospatial

Querying

Query

flexibility

M-to-M

access

Geospatial

Modelling

efforts

Scenario 1 Integrated with

GIS

+

Design

time

-

To be

implemented

-

Native

+

Scenario 2 Adhoc

-

Query

time

+

Native

+

To be

implemented

-

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 18

A possible solution: Scenario 1+2

The two

architectures

are integrated:

• On the

backend

exchangin

g data

• On the

frontend

serving

different

user

categories

Monica Scannapieco, NTTS, Brussels, 10 -12 March 2015 19

Conclusions

Linked Geospatial data are a key point for future

spatial web data integration, providing unique URIs

and exposing its content as Linked Data

Different architectures for visualization of

Geospatial linked open data can co-exist in NSIs

Questions?