GeoWeb, 3 years ago

36 Pages·2011·8.02 MB·English

Visual Information Systems Pr. Robert LAURINI
Chapter 4: Introduction to GeoWeb 1
Visual Information Systems Pr. Robert LAURINI
4.1 – Semantic Web / Geospatial Web Key-words of today’s web
• GIS Evolution
• New functionalities
• New mentalities
• All the citizens can contribute
From yesterday to today Evolution
Sametechnologies
Butthecontextisdifferent
Usersnotonlyread, butalso
contribute
So generatinga sortofcollective
intelligence
Creationofa Social Web
From 1993 (cid:1) To 2009 (cid:1)
Chapter 4: Introduction to GeoWeb 2
Visual Information Systems Pr. Robert LAURINI
Evolution
From 1993 (cid:1) From 2008 (cid:1)
Structured spatial data Non-structured spatial data
Google Earth (and Google Maps) Semantic Web
• Google Maps and Google Earth both have been • Transformation of the World Wide Web in an
released in 2005 (although Google Earth was bought
environment where the published (pages
from another firm)
• They have revolutionized the use of the spatial data HTML, file, images, and so on)
on the web
• Association of information and data
• Google Maps have offered some AP’s (application
planning interface) that have made easy to add (metadata)
additional data
– which specifies the semantic context of it in a
• The use of KML allows the consumers to manage
proper format
their own data in 3D
– for querying, to the interpretation and, in general,
• A big subset of the OGC vision of interoperability is
now happening through Google to the automatic elaboration.
Wikipedia: http://en.wikipedia.org/wiki/Semantic_Web
Chapter 4: Introduction to GeoWeb 3
Visual Information Systems Pr. Robert LAURINI
• With the interpretation of the content of the
Scope of Semantic Web
documents that the Semantic Web
advocates:
• Development of applications for:
– It will be possible to make more evolved searches
than the actual ones, based on the presence of – extraction of information from extemporaneous
key words in the document and collections / dynamics of documents
– other special operations such as the construction
– validity check of the contents
of network of relationships and connections
– identification of style
among documents according to more elaborate
mechanisms than the simple hypertext link – recognition of virtual hyperlink connections
– intelligent agents
GeoWeb Geoweb
• The Geospatial Web or Geowebis a relatively • Intelligent location
new term that implies the merging of
• Use of Internet
geographical (location-based) information
(cid:1)
• Toponyms location on the globe
with the abstract information that currently
dominates the Internet. • postal Address.
• This would create an environment where one • location on the globe
could search for things based on location
• Location-based relations
instead of by keyword only –i.e. “What is
Here?”. • Gazetteer
http://en.wikipedia.org/wiki/Geoweb
Chapter 4: Introduction to GeoWeb 4
Visual Information Systems Pr. Robert LAURINI
Three ingredients of web 2.0 Sharing
Web 1.0 Web 2.0
• Technological
– interactive Web, Information Agencies Blogs
– not more software products but services
Knowledge From writer to reader Wikipedia
• Sociological
– to belong to a community, Images Database/Usenet Community (Flickr)
– to interact with other members
Video Database/Usenet Community Youtube
• Economic
Condivisi
– Who provides the service spends few, but if in Bookmark Private (user) Del.icio.us
case of success, can earn a lot
Classification Taxonomy Folksonomy
Taxonomy / Folksonomy Mashup: What are they?
• Categories • Individual • Expression coming from pop music
• Classes • Attribute • Integration of several existing services for
• Rules • Suggestion generating fresh applications
• Projected • Implicit
– SOAP
• Precise • Fuzzy
– REST
• Deterministic • Probabilistic
– JavaScript
• Annoying • Immediate
– RSS/Atom
• Semantic Web • Web 2.0
• Used in catalogues • Used in the community
Chapter 4: Introduction to GeoWeb 5
Visual Information Systems Pr. Robert LAURINI
1 browser, 1000 applications Advantages for users
• E-mail (Gmail) • Ubiquity of applications
• Cartography (Gmaps, Yahoomaps, VirtualEarth)
• Zero-install
• Word processor (Writely, officelive)
• Continuous updating (each hour)
• Spreadsheet (Google spreadsheet)
• Encyclopedia (Wikipedia) • Data on-the-air
• Agenda (30 boxes, Gcalendar) • Multi-device
• Bookmarks (del.icio.us)
• News, podcast, ecc. (Bloglines)
• Programmation(zimki)
Immense problems for users Monopoly of new giants
• What do they do with our data? • Will every developer end up writing programs
that store them in their datacenters?
• How not to accept more than one certain
service, and to pass to a competing service? • The desktop is not the battleground anymore.
You are able by now to migrate from
• How can you migrate your own data,
metadata, annotations and all that the user Windows to Linux
and his community have produced? • Those giants invest billions of dollars in the
purchase and in the development of the Web
2.0 services (f.i. Youtube)
Chapter 4: Introduction to GeoWeb 6
Visual Information Systems Pr. Robert LAURINI
Geographic Information
Semantic Web Layer cake
Retrieval (GIR)
Machine-processable • A great deal of data is not structured
Global Web Standard
• An investigation on text document says
•Assignunambiguous
names(URI)
•Representdata and
– 85% out of 20 000 British documents integrate
metadata(RDF)
place names,
•Ontologicallanguage
(RDF schemaandOWL) – and 13% out of 4 million queries on Internet have
•Query languages some place names
-Alwaysaccessibleon
theWeb
Expansion of queries
GIR Key-elements
and spatial indexing
• Identification of footprints : identify place • Expansion : If Lyon, then add Villeurbanne,
names in non-structured texts Caluire, etc.
• Query expansion : add place names not • Necessity to know topology and neighboring
present in the initial query place names
• Spatial indexing and text indexing. • Using a gazetteer
• Ranking : according to theme and location. • If a user wants «castles around Zurich», a
spatial index must integrate only Zurich and
• Formulation of queries and result
visualization the vicinity
Chapter 4: Introduction to GeoWeb 7
Visual Information Systems Pr. Robert LAURINI
4.2 – Geocoding, Geonaming
Geocoding
Geoparsing and Geotagging
• Geocoding • Assigning coordinates to a place with
– Finding coordinates of a place
longitude and latitude
• Geonaming • Two representations
– Give a name to a place
– Degrees, minutes, second (gg°mm‘ss")
– Decimal degrees (gg, ddd)
• Geoparsing
– From a text, find the corresponding place ddd=mm/60+ss/3600
– Solving ambiguities – Certain cases: interpolation (f.e. roads)
•Linear interpolation for the numbers along the roads
• Geotagging
based the coordinates of the crossroads
– Annotate a place on a map
Chapter 4: Introduction to GeoWeb 8
Visual Information Systems Pr. Robert LAURINI
Geonaming GeoParsing
• From the coordinates of a place, assigning a name to • Analyzing for locating
this place
– line
– area Many-to-many
Placenames Places
• Problems of linguistics
– multilingual problem
• What name?
– Name in the official language of the country • Example: Mississipi(river/state ?)
– Name in the language of the user
• Example: Roma
– Name in the language of the system
GeoParsing: 3 definitions
(cid:1)
• Placenames Location (=coordinates)
– Where is located Cholula pyramid?
(cid:1)
• Relation to a placename Location
– At 15 Km Southwest of Oaxaca
(cid:1)
• Text Analysis Location
– Historical text, Bible, etc.
Chapter 4: Introduction to GeoWeb 9
Visual Information Systems Pr. Robert LAURINI
Instruments Difficulties for text analysis
• Gazetteers • MrsFlorence Manchester
2345 New York Avenue
97347 Aberdeen, WA
• List of placenames(toponyms)
• SeñorErnesto Madrid
• Languages
Garibaldi 345
– Venezia, Venice, Venise, Venecia, Venedig,
Vicente López
Benetke, Benátky... etc.
Argentina
– Monaco diBaviera, Monaco,
Web Sites for GeoParsing
• NGA GEOnetNames Server (GNS)
– http://earth-info.nga.mil/gns/html/
• BioGeoMancer
http://bg.berkeley.edu/latest/
• Edina GeoParser
– http://edina.ac.uk/projects/geoxwalk/geoparser.h
tml
• Etc.
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