Linked Data Tutorial (Florianópolis)

Mini-curso sobre LinkedDataOscar Corcho, Asunción Gómez Pérez ({ocorcho, asun}@fi.upm.es)Universidad Politécnica de MadridFlorianópolis, September 1st 2010(3º OntoBras 2010)Credits: Raúl García Castro, Oscar Muñoz, Jose Angel Ramos Gargantilla, María del Carmen Suárez de Figueroa, Boris Villazón, Alex de León, Víctor Saquicela, Luis Vilches, Miguel Angel García, Manuel Salvadores, Juan Sequeda, Carlos Ruiz Moreno and manyothersWorkdistributedunderthelicenseCreativeCommonsAttribution-Noncommercial-Share Alike 3.0

ContentsIntroductiontoLinked DataLinked Data Foundations: RDF, RDF Schema, SPARQL and OWLCoffee breakLinked Data publicationMethodologicalguidelinesforLinked Data publicationRDB2RDF toolsTechnicalaspects of Linked Data publicationLinked Data consumption2

Whatisthe Web of Linked Data?An extension of the current Web…… where information and services are given well-defined and explicitly represented meaning, …… so that it can be shared and used by humans and machines, ...... better enabling them to work in cooperationHow?Promoting information exchange by tagging web content with machineprocessable descriptions of its meaning. And technologies and infrastructure to do thisAnd clear principles on how to publish datadata

What is Linked Data?Linked Data is a term used to describe a recommended best practice for exposing, sharing, and connecting pieces of data, information, and knowledge on the Semantic Web using URIs and RDF.Part of the Semantic WebExposing, sharing and connecting dataTechnologies: URIs and RDF (although others are also important)

The fourprinciples (Tim Berners Lee, 2006)Use URIs as names for things Use HTTP URIs so that people can look up those names. When someone looks up a URI, provide useful information, using the standards (RDF*, SPARQL) Include links to other URIs, so that they can discover more things. http://www.w3.org/DesignIssues/LinkedData.html5http://www.ted.com/talks/tim_berners_lee_on_the_next_web.html

Linked Open Data evolution2007

20097LOD Cloud May 2007Facts:Focal points:

DBPedia: RDFizedvesion of Wikipiedia; many ingoing and outgoing links

Big datasets include FOAF, US Census data

Size approx. 1 billion triples, 250k linksFigure from [4]

8LOD Cloud September 2008Facts:More than 35 datasets interlinked

Commercial players joined the cloud, e.g., BBC

Companies began to publish and host dataset, e.g. OpenLink, Talis, or Garlik.

Size approx. 2 billion triples, 3 million linksFigure from [4]

9LOD Cloud March 2009Facts:Big part from Linking Open Drug cloud and the BIO2RDF project (bottom)

Notable new datasets: Freebase, OpenCalais, ACM/IEEE

Size > 10 billion triplesFigure from [4]

WhyLinked Data?Basically, tomovefrom a Web of documentsto a Web of DataLet’s try anexample:Tell me whichfootballplayers, born in theprovince of Albacete, in Spain, havescored a goal in theWorld Cup finalDisclaimer:Sorryto use anexampleaboutfootball, butyouhavetounderstandthatforseveralyearsSpaniardswillbetalkingaboutfootball a lot ;-)

Informationsearch in the Web of documents¿?What we were actually looking for

Itwouldbebettertomake a data query…(footballplayersfrom Albacete whoplayedEurocup 2008)

Howshouldwepublish data?Formats in which data ispublishednowadays…XMLHTMLDBsAPIsCSVXLS…However, mainlimitationsfrom a Web of Data point of viewDifficulttointegrateData isnotlinkedtoeachother, as ithappenswith Web documents.

Which format do we use then?RDF (ResourceDescription Framework)Data modelBasedon triples: subject, predicate, object<Oscar> <vive en> <Madrid><Madrid> <es la capital de> <España><España> <es campeona de> <Mundial de Fútbol>…Serialised in differentformatsRDF/XML, RDFa, N3, Turtle, JSON…

URIs (Universal-UniformResourceIdentifer)Two types of identifiers can be used to identify Linked Data resourcesURIRefs(Unique Resource IdentifiersReferences)A URI and an optional FragmentIdentifier separated from the URI by the hash symbol ‘#’http://www.ontology.org/people#Personpeople:PersonPlain URIs can also be used, as in FOAF:http://xmlns.com/foaf/0.1/Person17

How do wepublishLinked Data?ExposingRelationalDatabasesorother similar formatsintoLinked DataD2RTriplifyR2ONOR2OVirtuosoUltrawrap…Usingnative RDF triplestoresSesameJenaOwlimTalisplatform…Incorporatingit in theform of RDFa in CMSslikeDrupal18

How do we consume Linked Data?Linked Data browsersTo explore things and datasets and to navigate between them.Tabulator Browser (MIT, USA), Marbles (FU Berlin, DE), OpenLink RDF Browser (OpenLink, UK), Zitgist RDF Browser (Zitgist, USA), Disco Hyperdata Browser (FU Berlin, DE), Fenfire (DERI, Ireland)Linked Data mashupsSites that mash up (thus combine Linked data)Revyu.com (KMI, UK), DBtune Slashfacet (Queen Mary, UK), DBPedia Mobile (FU Berlin, DE), Semantic Web Pipes (DERI, Ireland) Search enginesTo search for Linked Data.Falcons (IWS, China), Sindice (DERI, Ireland), MicroSearch (Yahoo, Spain), Watson (Open University, UK), SWSE (DERI, Ireland), Swoogle (UMBC, USA)Listing on this slide by T. Heath, M. Hausenblas, C. Bizer, R. Cyganiak, O. Hartig19

Linked Data Mashup (LinkedGeoData)© Migración de datos a la Web de los Datos - Enfoques, técnicas y herramientasLuis Manuel Vilches Blázquez

Linked Data Mashup (DBpedia Mobile)http://wiki.dbpedia.org/DBpediaMobile© Migración de datos a la Web de los Datos - Enfoques, técnicas y herramientasLuis Manuel Vilches Blázquez

Linked Data Search Engines (Sindice and SIG.MA)Entity lookup service. Find a document that mentions a URI or a keyword.

Linked Data SearchEngines (NYT)The New York Times: Alumni In The Newshttp://data.nytimes.com/schools/schools.html

Linked Data SearchEngines (NYT)The New York Times: Source code is available… and is based on SPARQL queries

Oneadditionalmotivation: Open GovernmentGovernment and state administration should be opened at all levels to effective public scrutiny and oversightObjectives:TransparencyParticipationCollaborationInclusionCost reductionInteroperabilityReusabilityLeadershipMarket & Value26Some Links:

B. Obama –Transparency and Open Government

T. Berners-Lee - Raw data now!

J. Manuel Alonso - ¿Qué es Open Data?

8 Principles of Open Government DataOpen Government. USA and UK27BOTTOM-UPTop-down

Linked Data Mashup (data.gov)Clean Air Status and Trends (CASTNET)http://data-gov.tw.rpi.edu/demo/exhibit/demo-8-castnet.php

Linked Data in the UKEducationhttp://education.data.gov.uk/id/school/106661Parliamenthttp://parliament.psi.enakting.org/id/member/1227MapsE.g., London: http://data.ordnancesurvey.co.uk/id/7000000000041428http://map.psi.enakting.orgTransporthttp://www.dft.gov.uk/naptan/SameAs servicehttp://www.sameas.orgChallengeshttp://gov.tso.co.uk/openup/sparql/gov-transport29

Linked Data Mashup (data.gov.uk)Research Funding Explorerhttp://bis.clients.talis.com/

Open GovernmentSpain. Euskadi31

Open GovernmentSpain. Abredatos32

Open GovernmentSpain. Zaragoza 33

Open GovernmentSpain. Asturias34

Linked Data Mashup (Waterquality)Water quality in Asturias’ beacheshttp://datos.fundacionctic.org/sandbox/asturias/playas/

IndexResourceDescription Framework (RDF)RDF primitivesReasoningwith RDFRDF SchemaRDF SchemaprimitivesReasoningwith RDFSRDF(S) Management APIsSPARQLOWL37

RDF: Resource Description FrameworkW3C recommendationRDF is graphical formalism ( + XML syntax + semantics)For representing metadataFor describing the semantics of information in a machine- accessible wayResources are described in terms of properties andproperty values using RDF statementsStatements are represented as triples, consisting of asubject, predicate and object. [S, P, O]“Oscar Corcho García”person:hasNameperson:hasColleagueoeg:Oscaroeg:Asunperson:hasHomePageperson:hasColleague“http://www.fi.upm.es/”oeg:Raul38

RDF and URIsRDF uses URIRefs(Unique Resource IdentifiersReferences) toidentify resourcesA URIRef consists of a URI and an optional FragmentIdentifier separated from the URI by the hash symbol ‘#’Exampleshttp://www.co-ode.org/people#hasColleaguecoode:hasColleagueA set of URIRefs is known as a vocabularyE.g., the RDF Vocabulary The set of URIRefs used indescribing the RDF concepts:rdf:Property,rdf:Resource, rdf:type, etc.The RDFS Vocabulary The set of URIRefs used indescribing the RDF Schema language: rdfs:Class, rdfs:domain, etc.The ‘Pizza Ontology’ Vocabulary pz:hasTopping,pz:Pizza, pz:VegetarianPizza, etc.39

RDF SerialisationsNormativeRDF/XML (www.w3.org/TR/rdf-syntax-grammar/)Alternative (for human consumption)N3 (http://www.w3.org/DesignIssues/Notation3.html)Turtle (http://www.dajobe.org/2004/01/turtle/)TriX (http://www.w3.org/2004/03/trix/)…Important: the RDF serializations allow different syntactic variants. E.g., the order of RDF statements has no meaning40

RDF Serialisations. RDF/XML<?xml version="1.0"?><rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:person="http://www.ontologies.org/ontologies/people#" xmlns="http://www.oeg-upm.net/ontologies/people#" xml:base="http://www.oeg-upm.net/ontologies/people"> <rdf:Property rdf:about="http://www.ontologies.org/ontologies/people#hasHomePage"/> <rdf:Property rdf:about="http://www.ontologies.org/ontologies/people#hasColleague"/> <rdf:Property rdf:about="http://www.ontologies.org/ontologies/people#hasName"/> <rdf:Description rdf:about="#Raul"/> <rdf:Description rdf:about="#Asun"> <person:hasColleague rdf:resource="#Raul"/> <person:hasHomePage>http://www.fi.upm.es</person:hasHomePage> </rdf:Description> <rdf:Description rdf:about="#Oscar"> <person:hasColleague rdf:resource="#Asun"/> <person:hasName>Oscar Corcho García</person:hasName> </rdf:Description></rdf:RDF>41

RDF Serialisations. N3@base <http://www.oeg-upm.net/ontologies/people >@prefix person: <http://www.ontologies.org/ontologies/people#>:Asun person:hasColleague :Raul ; person:hasHomePage “http://www.fi.upm.es/”.:Oscar person:hasColleague :Asun ; person:hasName “Óscar Corcho García”.42

Getusedtothedifferentsyntaxesof RDF

Takethetextofan RDF file andcreateitscorrespondinggraph

Takean RDF graphandcreateitscorresponding RDF/XML and N3 files 43

Exercise 1.a. Create a graph from a fileOpen the file StickyNote_PureRDF.rdfCreate the corresponding graph from itCompare your graph with those of your colleagues44

Exercise 1.a. StickyNote_PureRDF.rdf45

Exercise 1.b. Create files from a graphTransform the following graph into N3 syntax46hasMeasurementMeasurement8401Sensor029includeshasTemperatureatTimeClass01includes2010-06-12T12:00:1229Computer101hasOwnerUser10AhasNamePedro

Blank nodes: structured property valuesMost real-world data involves structures that are more complicated than sets of RDF triple statementsIn RDF/XML, it is an <rdf:Description> node with no rdf:aboutIn N3, it is a resource identifier that starts with ‘_’ E.g., “_:nodeX”Thisintermediate URI doesnotneedtohave a name“Oscar Corcho García”person:hasNameperson:hasPostalAddressoeg:Oscaraddress:hasStreetNameaddress:cityCampus de Montegancedo s/ncity:BoadillaDelMonte47

Typed literalsSo far, all values have been presented as stringsXML Schema datatypes can be used to specify values (objects in some RDF triple statements)In RDF/XML, this is expressed as:<rdf:Description rdf:about=”#Oscar”> <person:hasBirthDate rdf:datatype="http://www.w3.org/2001/XMLSchema#date">1976-02-02 </person:hasBirthDate></rdf:Description>In N3, this is expressed as:oeg:Oscar person:hasBirthDate ”1976-02-02”^^xsd:date .person:hasBirthDateoeg:Oscar1976-02-0248

RDF ContainersThere is often the need to describe groups of thingsA book was created by several authorsA lesson is taught by several personsetc.RDF provides a container vocabularyrdf:Bag  A group of resources or literals, possibly including duplicate members, where the order of members is not significantrdf:Seq  A group of resources or literals, possibly including duplicate members, where the order of members is significantrdf:Alt  A group of resources or literals that are alternatives (typically for a single value of a property)rdf:typeperson:hasEmailAddressoeg:Oscarrdf:Seqrdf:_2rdf:_1“oscar.corcho@upm.es”“ocorcho@fi.upm.es”49

RDF ReificationRDF statements about other RDF statements“Raúl believes that Oscar’s birthdate is on Feb 2nd, 1976 and that his e-mail address is ocorcho@fi.upm.es”RDF ReificationAllows expressing beliefs (and other modalities)Allows expressing trust models, digital signatures, etc.Allows expressing metadata about metadatamodal:believesoeg:Raúloeg:Oscarperson:hasBirthDateperson:hasEmailAddress02/02/1976“ocorcho@fi.upm.es”50

Main value of a structured valueSometimes one of the values of a structured value is the main oneThe weight of an item is 2.4 kilograms The most important value is 2.4, which is expressed with rdf:valueScarcely usedproduct:hasWeightproduct:Item1rdf:valueunits:hasWeightUnitunits:kilogram2.451

RDF inference. Graph matching techniques RDF inference is based on graph matching techniquesBasically, the RDF inference process consists of the following steps:Transform an RDF query into a template graph that has to be matched against the RDF graphIt contains constant and variable nodes, and constant and variable edges between nodesMatch against the RDF graph, taking into account constant nodes and edgesProvide a solution for variable nodes and edges53

RDF inference. Examples (I)Sample RDF graphQuery: “Tell me who are the persons who have Asun as a colleague”Result: oeg:Oscar and oeg:Raúl“Oscar Corcho García”person:hasNameperson:hasColleagueoeg:Oscaroeg:Asunperson:hasHomePageperson:hasColleague“http://www.fi.upm.es/”oeg:Raúlperson:hasColleague?oeg:Asun54

RDF inference. Examples (II)Query: “Tell me which are the relationships between Oscar and Asun”Result: oeg:hasColleagueQuery: “Tell me the homepage of Oscar colleagues”Result: “http://www.fi.upm.es/”?oeg:Oscaroeg:Asunperson:hasColleagueoeg:Oscarperson:hasHomePage?55

RDF inference. Entailment rules56

RDFS: RDF SchemaW3C RecommendationRDF Schema extends RDF to enable talking about classes of resources, and the properties to be used with themClass definition: rdfs:Class, rdfs:subClassOfProperty definition: rdfs:subPropertyOf, rdfs:range, rdfs:domainOther primitives: rdfs:comment, rdfs:label, rdfs:seeAlso, rdfs:isDefinedByRDFS vocabulary adds constraints on models, e.g.:x,y,ztype(x,y) and subClassOf(y,z) type(x,z)ex:Animalrdfs:subClassOfrdf:typeex:Oscarex:Person58

RDF(S) Serialisations. RDF/XML syntax<?xml version="1.0"?><rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:person="http://www.ontologies.org/ontologies/people#" xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#" xmlns="http://www.oeg-upm.net/ontologies/people#" xml:base="http://www.oeg-upm.net/ontologies/people"> <rdfs:Class rdf:about="http://www.ontologies.org/ontologies/people#Professor"> <rdfs:subClassOf> <rdfs:Class rdf:about="http://www.ontologies.org/ontologies/people#Person"/> </rdfs:subClassOf> </rdfs:Class> <rdfs:Class rdf:about="http://www.ontologies.org/ontologies/people#Lecturer"> <rdfs:subClassOf rdf:resource="http://www.ontologies.org/ontologies/people#Person"/> </rdfs:Class> <rdfs:Class rdf:about="http://www.ontologies.org/ontologies/people#PhD"> <rdfs:subClassOf rdf:resource="http://www.ontologies.org/ontologies/people#Person"/> </rdfs:Class> …59

RDF(S) Serialisations. RDF/XML syntax… <rdf:Property rdf:about="http://www.ontologies.org/ontologies/people#hasHomePage"/> <rdf:Property rdf:about="http://www.ontologies.org/ontologies/people#hasColleague"> <rdfs:domain rdf:resource=" http://www.ontologies.org/ontologies/people#Person"/> <rdfs:range rdf:resource=" http://www.ontologies.org/ontologies/people#Person"/> </rdf:Property> <rdf:Property rdf:about="http://www.ontologies.org/ontologies/people#hasName"> <rdfs:domain rdf:resource="http://www.w3.org/2002/07/owl#Thing"/> </rdf:Property> <person:PhD rdf:ID="Raul"/> <person:Professor rdf:ID=“Asun"> <person:hasColleague rdf:resource="#Raul"/> <person:hasHomePage>http://www.fi.upm.es</person:hasHomePage> </person:Professor> <person:Lecturer rdf:ID="Oscar"> <person:hasColleague rdf:resource="#Asun"/> <person:hasName>Óscar Corcho García</person:hasName> </person:Lecturer></rdf:RDF>60

RDF(S) Serialisations. N3@base <http://www.oeg-upm.net/ontologies/people >@prefix person: <http://www.ontologies.org/ontologies/people#>person:hasColleague a rdf:Property; rdfs:domain person:Person; rdfs:range person:Person.person:Professor rdfs:subClassOf person:Person.person:Lecturer rdfs:subClassOf person:Person.person:PhD rdfs:subClassOf person:Person.:Asun a person:Professor; person:hasColleague :Raul ; person:hasHomePage “http://www.fi.upm.es/”.:Oscar a person:Lecturer; person:hasColleague :Asun ; person:hasName “Óscar Corcho García”.:Raul a person:PhD.a is equivalent to rdf:type61

RDFSrdfs:Literalrdfs:Classrdf:Typerdfs:rangeFlightrdfs:domainarrivalDaterdf:Typerdfs:domainrdfs:domainrdfs:domaindepartureDatecompany-namesingleFarerdfs:rangerdfs:rangerdf:Typerdfs:rangeunits:currencyQuantityrdf:Typetime:Daterdf:Typerdf:TypeRDFrdf:Propertyrdf:Typerdf:Typecompany-namerdf:TypeIB-4321“Iberia”arrivalDatesingleFaredepartureDate10/11/2005500 eurosRDF(S) Example62

GetusedtothedifferentsyntaxesofRDF(S)

TakethetextofanRDF(S) file andcreateitscorrespondinggraph

TakeanRDF(S) graphandcreateitscorresponding RDF/XML and N3 files 63

Exercise 2.a. Create a graph from a fileOpen the files StickyNote.rdf and StickyNote.rdfsCreate the corresponding graph from themCompare your graph with those of your colleagues64

Exercise 2.a. StickyNote.rdf65

Exercise 2.a. StickyNote.rdfs66

Exercise 2.b. Create files from a graphTransform the following graph into N3 syntax67RoomPersonMeasurementObjecthasMeasurementSensor029includeshasTemperatureatTimeClass01includes2010-06-12T12:00:1229Computer101hasOwnerUser10AhasNamePedro

RDF(S) inference. Entailment rules69

RDF(S) inference. Additional inferences 70

RDF(S) limitationsRDFS too weak to describe resources in sufficient detailNo localised range and domain constraintsCan’t say that the range of hasChild is person when applied to persons and elephant when applied to elephantsNo existence/cardinality constraintsCan’t say that all instances of person have a mother that is also a person, or that persons have exactly 2 parentsNo boolean operatorsCan’t say or, not, etc.No transitive, inverse or symmetrical propertiesCan’t say that isPartOf is a transitive property, that hasPart is the inverse of isPartOf or that touches is symmetricalDifficult to provide reasoning supportNo “native” reasoners for non-standard semanticsMay be possible to reason via FOL axiomatisation71

Understand the features of RDF(S) for implementing ontologies, including its limitations

Given a scenario description, build a simple ontology in RDF Schema72

Exercise 3. Domain descriptionUn lugar puede ser un lugar de interés.Los lugares de interés pueden ser lugares turísticos o establecimientos, pero no las dos cosas a la vez.Los lugares turísticos pueden ser palacios, iglesias, ermitas y catedrales.Los establecimientos pueden ser hoteles, hostales o albergues.Un lugar está situado en una localidad, la cual a su vez puede ser una villa, un pueblo o una ciudad.Un lugar de interés tiene una dirección postal que incluye su calle y su número.Las localidades tienen un número de habitantes.Las localidades se encuentran situadas en provincias.Covarrubias es un pueblo con 634 habitantes de la provincia de Burgos.El restaurante “El Galo” está situado en Covarrubias, en la calle Mayor, número 5.Una de las iglesias de Covarrubias está en la calle de Santo Tomás.73

Exercise 3. Sample resulting ontology74

Sample RDF APIsRDF libraries for different languages: Java, Python, C, C++, C#, .Net, Javascript, Tcl/Tk, PHP, Lisp, Obj-C, Prolog, Perl, Ruby, HaskellList in http://esw.w3.org/topic/SemanticWebToolsUsually related to a RDF repositoryMultilanguage:Redland RDF Application Framework (C, Perl, PHP, Python and Ruby): http://www.redland.opensource.ac.uk/Java:Jena: http://jena.sourceforge.net/Sesame: http://www.openrdf.org/PHP:RAP - RDF API for PHP: http://www4.wiwiss.fu-berlin.de/bizer/rdfapi/Python:RDFLib: http://rdflib.net/Pyrple: http://infomesh.net/pyrple/76

JenaJava framework for building Semantic Web applicationsOpen source software from HP LabsThe Jena framework includes:A RDF APIAn OWL APIReading and writing RDF in RDF/XML, N3 and N-TriplesIn-memory and persistent storageA rule based inference engineSPARQL query engine77

SesameA framework for storage, querying and inferencing of RDF and RDF SchemaA Java Library for handling RDFA Database Server for (remote) access to repositories of RDF dataHighly expressive query and transformation languagesSeRQL, SPARQLVarious backendsNative StoreRDBMS (MySQL, Oracle 10, DB2, PostgreSQL)main memoryReasoning supportRDF Schema reasonerOWL DLP (OWLIM)domain reasoning (custom rule engine)78

Jena example. Graph creationhttp://.../JohnSmithvcard:FNvcard:NJohn Smithvcard:Givenvcard:FamilySmithJohn// some definitions String personURI = "http://somewhere/JohnSmith"; String givenName = "John"; String familyName = "Smith"; String fullName = givenName + " " + familyName; // create an empty Model Model model = ModelFactory.createDefaultModel(); // create the resource // and add the properties cascading style Resource johnSmith = model.createResource(personURI) .addProperty(VCARD.FN, fullName) .addProperty(VCARD.N, model.createResource() .addProperty(VCARD.Given, givenName) .addProperty(VCARD.Family, familyName)); 79

Jena example. Read and write// create an empty modelModel model = ModelFactory.createDefaultModel();// use the FileManager to find the input fileInputStream in = FileManager.get().open( inputFileName );if (in == null) { throw new IllegalArgumentException("File not found");}// read the RDF/XML filemodel.read(in, "");// write it to standard outmodel.write(System.out);<rdf:RDF xmlns:rdf='http://www.w3.org/1999/02/22-rdf-syntax-ns#' xmlns:vcard='http://www.w3.org/2001/vcard-rdf/3.0#' > <rdf:Description rdf:nodeID="A0"> <vcard:Family>Smith</vcard:Family> <vcard:Given>John</vcard:Given> </rdf:Description> <rdf:Description rdf:about='http://somewhere/JohnSmith/'> <vcard:FN>John Smith</vcard:FN> <vcard:N rdf:nodeID="A0"/> </rdf:Description>...</rdf:RDF>80

Some RDF editorsIsaVizhttp://www.w3.org/2001/11/IsaViz/Morlahttp://www.morlardf.net/RDFAuthorhttp://rdfweb.org/people/damian/RDFAuthor/RdfGravityhttp://semweb.salzburgresearch.at/apps/rdf-gravity/Rhodonitehttp://rhodonite.angelite.nl/81

Main ReferencesBrickley D, Guha RV (2004) RDF Vocabulary Description Language 1.0: RDF Schema. W3C Recommendationhttp://www.w3.org/TR/PR-rdf-schema/Lassila O, Swick R (1999) Resource Description Framework (RDF) Model and Syntax Specification. W3C Recommendation http://www.w3.org/TR/REC-rdf-syntax/RDF validator: http://www.w3.org/RDF/Validator/RDF resources:http://planetrdf.com/guide/82

RDF(S) query languagesLanguages developed to allow accessing datasets expressed in RDF(S) (and in some cases OWL)Supported by the most important language APIsJena (HP labs)Sesame (Aduna)Boca (IBM)...There are some differences wrt. languages like SQL, such asCombination of different sourcesTrust managementOpen World Assumption84ApplicationApplicationSQL queriesSPARQL, RQL, etc., queriesRelationalDBRDF(S)OWL

Query typesSelection and extraction“Select all the essays, together with their authors and their authors’ names”“Select everything that is related to the book ‘Bellum Civille’” Reduction: we specify what it should not be returned“Select everything except for the ontological information and the book translators”Restructuring: the original structure is changed in the final result“Invert the relationship ‘author’ by ‘is author of’”Aggregation“Return all the essays together with the mean number of authors per essay”Combination and inferences“Combine the information of a book called ‘La guerra civil’ and whose author is Julius Caesar with the book whose identifier is ‘Bellum Civille’”“Select all the essays, together with its authors and author names”, including also the instances of the subclasses of Essay“Obtain the relationship ‘coauthor’ among persons who have written the same book”85

RDF(S) query language familiesSPARQL W3C Recommendation 15 January 2008Description graphsQuery semanticsTriple database Query structureSquishQLFamilySquishQLrdfDB Query LanguageRDQLBRQLTriQLXPath, XSLT, XQueryXQueryfor RDFXsRQLTreeHuggerandRDFTwigRDFT, Nexus Query LanguageRDFPath, RpathandRXPathVersaRQL FamilyRQLSeRQLeRQLControlled natural languageMetalogOtherAlgaeiTQLN3QLPerlRDF Query LanguageRDEVICE DeductiveLanguageRDFQBERDFQLTRIPLEWQLXML repository Query syntax86

SPARQLSPARQL Protocol and RDF Query LanguageSupported by: Jena, Sesame, IBM Boca, etc.FeaturesItsupportsmostoftheaforementionedqueriesItsupportsdatatypereasoning(datatypes can be requestedinsteadof actual values)Thedomainvocabularyandtheknowledgerepresentationvocabularyare treateddifferently by thequeryinterpretersItallowsmakingqueriesoverpropertieswithmultiplevalues, overmultiplepropertiesof a resourceandoverreificationsQueries can containoptionalstatementsSomeimplementationssupportaggregationqueriesLimitationsNeitherset operationsnorexistentialor universal quantifierscan be included in thequeriesItdoesnotsupportrecursivequeries87

SPARQL is also a protocolSPARQL is a Query Language …Find names and websites of contributors to PlanetRDF: PREFIX foaf: <http://xmlns.com/foaf/0.1/> SELECT ?name ?website FROM <http://planetrdf.com/bloggers.rdf> WHERE { ?person foaf:weblog ?website . ?person foaf:name ?name . ?website a foaf:Document }... and a Protocolhttp://.../qps?query-lang=http://www.w3.org/TR/rdf-sparql-query/ &graph-id=http://planetrdf.com/bloggers.rdf&query=PREFIXfoaf: <http://xmlns.com/foaf/0.1/...Services running SPARQL queries over a set of graphs A transport protocol for invoking the service Based on ideas from earlier protocol work such as JosekiDescribing the service with Web Service technologies 88

SPARQL EndpointsSPARQL protocol servicesEnables users (human or other) to query a knowledge base using SPARQLResults are typically returned in one or more machine-processable formatsList of SPARQL Endpointshttp://esw.w3.org/topic/SparqlEndpointsProgrammatic access using libraries:ARC, RAP, Jena, Sesame, Javascript SPARQL, PySPARQL, etc.Examples:89

Example: Querying dbpediaPeople who were born in Berlin before 190090

A simple SPARQL queryData:@prefix dc: <http://purl.org/dc/elements/1.1/> . @prefix : <http://example.org/book/> . :book1 dc:title "SPARQL Tutorial" .Query:SELECT ?titleWHERE{ <http://example.org/book/book1> <http://purl.org/dc/elements/1.1/title> ?title .}Query result:A pattern is matched against the RDF data

Each way a pattern can be matched yields a solution

The sequence of solutions is filtered by: Project, distinct, order, limit/offset

One of the result forms is applied: SELECT, CONSTRUCT, DESCRIBE, ASK91

Graph patternsBasic Graph Patterns, where a set of triple patterns must matchGroup Graph Pattern, where a set of graph patterns must all matchOptional Graph patterns, where additional patterns may extend the solutionAlternative Graph Pattern, where two or more possible patterns are triedPatterns on Named Graphs, where patterns are matched against named graphs92

@prefix foaf: <http://xmlns.com/foaf/0.1/> ._:a foaf:name "Johnny Lee Outlaw" ._:a foaf:mbox <mailto:jlow@example.com> ._:bfoaf:name "Peter Goodguy" ._:bfoaf:mbox <mailto:peter@example.org> ._:cfoaf:mbox <mailto:carol@example.org> .PREFIX foaf: <http://xmlns.com/foaf/0.1/>SELECT ?name ?mboxWHERE { ?x foaf:name ?name . ?x foaf:mbox ?mbox }Multiple matches93

@prefix dt: <http://example.org/datatype#> .@prefix ns: <http://example.org/ns#> .@prefix : <http://example.org/ns#> .@prefix xsd: <http://www.w3.org/2001/XMLSchema#> .:x ns:p "cat"@en .:y ns:p "42"^^xsd:integer .:z ns:p "abc"^^dt:specialDatatype .SELECT ?v WHERE { ?v ?p "cat" }SELECT ?v WHERE { ?v ?p "cat"@en }SELECT ?v WHERE { ?v ?p 42 }SELECT ?v WHERE { ?v ?p "abc"^^<http://example.org/datatype#specialDatatype> }Matching RDF literals94

@prefix foaf: <http://xmlns.com/foaf/0.1/> ._:a foaf:name "Alice" ._:bfoaf:name "Bob" .PREFIX foaf: <http://xmlns.com/foaf/0.1/>SELECT ?x ?nameWHERE { ?x foaf:name ?name }=Blank node labels in query results95

Group graph patternPREFIX foaf: <http://xmlns.com/foaf/0.1/>SELECT ?name ?mboxWHERE { { ?xfoaf:name ?name . } { ?xfoaf:mbox ?mbox . } }SELECT ?xWHERE {}PREFIX foaf: <http://xmlns.com/foaf/0.1/>SELECT ?name ?mboxWHERE { { ?x foaf:name ?name . } { ?x foaf:mbox ?mbox . FILTER regex(?name, "Smith")} }96

Optional graph patterns@prefix foaf: <http://xmlns.com/foaf/0.1/> .@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> ._:a rdf:typefoaf:Person ._:a foaf:name "Alice" ._:a foaf:mbox <mailto:alice@example.com> ._:a foaf:mbox <mailto:alice@work.example> ._:brdf:typefoaf:Person ._:bfoaf:name "Bob" .PREFIX foaf: <http://xmlns.com/foaf/0.1/>SELECT ?name ?mboxWHERE { ?x foaf:name ?name .OPTIONAL { ?x foaf:mbox ?mbox } }97

Multiple optional graph patterns@prefix foaf: <http://xmlns.com/foaf/0.1/> ._:a foaf:name "Alice" ._:a foaf:homepage <http://work.example.org/alice/> ._:bfoaf:name "Bob" ._:bfoaf:mbox <mailto:bob@work.example> .PREFIX foaf: <http://xmlns.com/foaf/0.1/>SELECT ?name ?mbox ?hpageWHERE { ?x foaf:name ?name .OPTIONAL { ?x foaf:mbox ?mbox } . OPTIONAL { ?x foaf:homepage ?hpage } }98

Alternative graph patterns@prefix dc10: <http://purl.org/dc/elements/1.0/> .@prefix dc11: <http://purl.org/dc/elements/1.1/> ._:a dc10:title "SPARQL Query Language Tutorial" ._:a dc10:creator "Alice" ._:b dc11:title "SPARQL Protocol Tutorial" ._:b dc11:creator "Bob" ._:c dc10:title "SPARQL" ._:c dc11:title "SPARQL (updated)" .PREFIX dc10: <http://purl.org/dc/elements/1.0/>PREFIX dc11: <http://purl.org/dc/elements/1.1/>SELECT ?titleWHERE { { ?book dc10:title ?title } UNION { ?book dc11:title ?title } }SELECT ?x ?yWHERE { { ?book dc10:title ?x } UNION { ?book dc11:title ?y } }SELECT ?title ?authorWHERE { { ?book dc10:title ?title . ?book dc10:creator ?author }UNION { ?book dc11:title ?title . ?book dc11:creator ?author }}99

Patterns on named graphs# Named graph: http://example.org/foaf/aliceFoaf@prefix foaf:<http://.../foaf/0.1/> .@prefix rdf:<http://.../1999/02/22-rdf-syntax-ns#> .@prefix rdfs:<http://.../2000/01/rdf-schema#> ._:a foaf:name "Alice" ._:a foaf:mbox <mailto:alice@work.example> ._:a foaf:knows _:b ._:b foaf:name "Bob" ._:b foaf:mbox <mailto:bob@work.example> ._:b foaf:nick "Bobby" ._:b rdfs:seeAlso <http://example.org/foaf/bobFoaf> .<http://example.org/foaf/bobFoaf> rdf:type foaf:PersonalProfileDocument .# Named graph: http://example.org/foaf/bobFoaf@prefix foaf:<http://.../foaf/0.1/> .@prefix rdf:<http://.../1999/02/22-rdf-syntax-ns#> .@prefix rdfs:<http://.../2000/01/rdf-schema#> ._:z foaf:mbox <mailto:bob@work.example> ._:z rdfs:seeAlso <http://example.org/foaf/bobFoaf> ._:z foaf:nick "Robert" .<http://example.org/foaf/bobFoaf> rdf:type foaf:PersonalProfileDocument .100

Patterns on named graphs IIPREFIX foaf: <http://xmlns.com/foaf/0.1/>SELECT ?src ?bobNickFROM NAMED <http://example.org/foaf/aliceFoaf>FROM NAMED <http://example.org/foaf/bobFoaf>WHERE {GRAPH ?src { ?xfoaf:mbox <mailto:bob@work.example> . ?xfoaf:nick ?bobNick } }PREFIX foaf: <http://xmlns.com/foaf/0.1/>PREFIX data: <http://example.org/foaf/>SELECT ?nickFROM NAMED <http://example.org/foaf/aliceFoaf>FROM NAMED <http://example.org/foaf/bobFoaf>WHERE {GRAPH data:bobFoaf { ?x foaf:mbox <mailto:bob@work.example> . ?x foaf:nick ?nick } }101

Restricting values@prefix dc: <http://purl.org/dc/elements/1.1/> .@prefix : <http://example.org/book/> .@prefix ns: <http://example.org/ns#> .:book1 dc:title "SPARQL Tutorial" .:book1 ns:price 42 .:book2 dc:title "The Semantic Web" .:book2 ns:price 23 .PREFIX dc: <http://purl.org/dc/elements/1.1/>SELECT ?titleWHERE { ?x dc:title ?titleFILTER regex(?title, "^SPARQL") }PREFIX dc: <http://purl.org/dc/elements/1.1/>SELECT ?titleWHERE { ?x dc:title ?titleFILTER regex(?title, "web", "i" ) }PREFIX dc: <http://purl.org/dc/elements/1.1/>PREFIX ns: <http://example.org/ns#>SELECT ?title ?priceWHERE { ?x ns:price ?price .FILTER (?price < 30.5) ?x dc:title ?title . }102

Value testsBased on XQuery 1.0 and XPath 2.0 Function and Operators XSD boolean, string, integer, decimal, float, double, dateTime Notation <, >, =, <=, >= and != for value comparisonApply to any type BOUND, isURI, isBLANK, isLITERAL REGEX, LANG, DATATYPE, STR (lexical form) Function call for casting and extensions functions 103

Solution sequences and modifiersSELECT ?nameWHERE { ?x foaf:name ?name ; :empId ?emp }ORDER BY ?name DESC(?emp)Order modifier: put the solutions in orderProjection modifier: choose certain variablesDistinct modifier: ensure solutions in the sequence are uniqueReduced modifier: permit elimination of some non-unique solutionsLimit modifier: restrict the number of solutionsOffset modifier: control where the solutions start from in the overall sequence of solutionsSELECT ?nameWHERE { ?x foaf:name ?name }SELECT DISTINCT ?name WHERE { ?x foaf:name ?name }SELECT REDUCED ?name WHERE { ?x foaf:name ?name }SELECT ?nameWHERE { ?x foaf:name ?name }LIMIT 20SELECT ?name WHERE { ?x foaf:name ?name }ORDER BY ?nameLIMIT 5OFFSET 10104

SPARQL query formsSELECTReturns all, or a subset of, the variables bound in a query pattern matchCONSTRUCTReturns an RDF graph constructed by substituting variables in a set of triple templatesASKReturns a boolean indicating whether a query pattern matches or notDESCRIBEReturns an RDF graph that describes the resources found105

SPARQL query forms: SELECT@prefix foaf: <http://xmlns.com/foaf/0.1/> ._:a foaf:name "Alice" ._:a foaf:knows _:b ._:a foaf:knows _:c ._:bfoaf:name "Bob" ._:cfoaf:name "Clare" ._:cfoaf:nick "CT" .PREFIX foaf: <http://xmlns.com/foaf/0.1/>SELECT ?nameX ?nameY ?nickYWHERE { ?x foaf:knows ?y ; foaf:name ?nameX . ?y foaf:name ?nameY . OPTIONAL { ?y foaf:nick ?nickY } }106

@prefix foaf: <http://xmlns.com/foaf/0.1/> ._:a foaf:name "Alice" ._:a foaf:mbox <mailto:alice@example.org> .PREFIX foaf: <http://xmlns.com/foaf/0.1/>PREFIX vcard: <http://www.w3.org/2001/vcard-rdf/3.0#>CONSTRUCT { <http://example.org/person#Alice> vcard:FN ?name }WHERE { ?x foaf:name ?name }Query result:@prefix vcard: <http://www.w3.org/2001/vcard-rdf/3.0#> .<http://example.org/person#Alice> vcard:FN "Alice" .SPARQL query forms: CONSTRUCT107

SPARQL query forms: ASK@prefix foaf: <http://xmlns.com/foaf/0.1/> ._:a foaf:name "Alice" ._:a foaf:homepage <http://work.example.org/alice/> ._:b foaf:name "Bob" ._:b foaf:mbox <mailto:bob@work.example> .PREFIX foaf: <http://xmlns.com/foaf/0.1/>ASK { ?xfoaf:name "Alice" }Query result:yes108

PREFIX ent: <http://org.example.com/employees#>DESCRIBE ?x WHERE { ?xent:employeeId "1234" }Query result:@prefix foaf: <http://xmlns.com/foaf/0.1/> .@prefix vcard: <http://www.w3.org/2001/vcard-rdf/3.0> .@prefix exOrg: <http://org.example.com/employees#> .@prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> .@prefix owl: <http://www.w3.org/2002/07/owl#>_:a exOrg:employeeId "1234" ; foaf:mbox_sha1sum "ABCD1234" ; vcard:N [ vcard:Family "Smith" ; vcard:Given "John" ] .foaf:mbox_sha1sum rdf:type owl:InverseFunctionalProperty .SPARQL query forms: DESCRIBE109

Main ReferencesPrud’hommeaux E, Seaborne A (2008) SPARQL Query Language for RDF. W3C Recommendation http://www.w3.org/TR/rdf-sparql-query/SPARQL validator: http://www.sparql.org/validator.htmlSPARQL implementations: http://esw.w3.org/topic/SparqlImplementationsSPARQL Endpoints http://esw.w3.org/topic/SparqlEndpointsSPARQL in Dbpediahttp://dbpedia.org/sparql110

Description LogicsA family of logic based Knowledge Representation formalismsDescendants of semantic networks and KL-ONEDescribe domain in terms of concepts (classes), roles (relationships) and individualsSpecificlanguagescharacterisedbytheconstructors and axiomsusedtoassertknowledgeaboutclasses, roles and individuals.Example: ALC (theleastexpressivelanguage in DL thatispropositionallyclosed)Constructors: boolean(and, or, not)Role restrictionsDistinguished by:Model theoretic semanticsDecidable fragments of FOLClosely related to Propositional Modal & Dynamic LogicsProvision of inference servicesSound and complete decision procedures for key problemsImplemented systems (highly optimised)

Structure of DL OntologiesA DL ontology can be divided into two parts:Tbox (Terminological KB): a set of axioms that describe the structure of a domain :Doctor  PersonPerson  Man  WomanHappyFather  Man  hasDescendant.(Doctor  hasDescendant.Doctor)Abox (Assertional KB): a set of axioms that describe a specific situation :John  HappyFather hasDescendant (John, Mary)

Mostcommonconstructors in classdefinitionsIntersection: C1 ...  Cn Human  MaleUnion: C1  ...  Cn Doctor  LawyerNegation: C MaleNominals: {x1}  ...  {xn} {john}  ...  {mary}Universal restriction: P.C hasChild.DoctorExistentialrestriction: P.C hasChild.LawyerMaximumcardinality: nP.C 3hasChild.DoctorMinimumcardinality: nP.C 1hasChild.MaleSpecificValue: P.{x} hasColleague.{Matthew}Nesting of constructors can bearbitrarilycomplexPerson hasChild.(Doctor hasChild.Doctor)Lots of redundancyAB is equivalent to ( A  B)P.C is equivalent to P. C

OWL (1.0 and 1.1)February 2004Web Ontology LanguageBuilt on top of RDF(S)Three layers: OWL Lite

Easier for frame-based tools to transition to

RDF extension, allows metaclassesSeveral syntaxes: Abstract syntax

RDF/XMLOWL 2 (I). New featuresOctober 2009New featuresSyntactic sugarDisjoint union of classesNew expressivityKeysProperty chainsRicher datatypes, data rangesQualified cardinality restrictionsAsymmetric, reflexive, and disjoint propertiesEnhanced annotation capabilities New syntaxOWL2 Manchester syntax

OWL 2 (II). Three new profilesOWL2 ELOntologies that define very large numbers of classes and/or properties, Ontology consistency, class expression subsumption, and instance checking can be decided in polynomial time. OWL2 QLSound and complete query answering is in LOGSPACE (more precisely, in AC0) with respect to the size of the data (assertions),Provides many of the main features necessary to express conceptual models (UML class diagrams and ER diagrams). It contains the intersection of RDFS and OWL 2 DL.OWL2 RLInspired by Description Logic Programs and pD*. Syntactic subset of OWL 2 which is amenable to implementation using rule-based technologies, and presenting a partial axiomatization of the OWL 2 RDF-Based Semantics in the form of first-order implications that can be used as the basis for such an implementation. Scalable reasoning without sacrificing too much expressive power. Designed forOWL applications trading the full expressivity of the language for efficiency, RDF(S) applications that need some added expressivity from OWL 2.

OWL: Most common constructorsIntersection: C1 ...  CnintersectionOf Human  MaleUnion: C1  ...  CnunionOf Doctor  LawyerNegation: C complementOf MaleNominals: {x1}  ...  {xn} oneOf {john}  ...  {mary}Universal restriction: P.C allValuesFrom hasChild.DoctorExistentialrestriction: P.C someValuesFrom hasChild.LawyerMaximumcardinality: nP[.C] maxCardinality (qualifiedornot) 3hasChild[.Doctor]Minimumcardinality: nP[.C] minCardinality (qualifiedornot) 1hasChild[.Male]Exactcardinality: =nP[.C] exactCardinality (qualifiedornot) =1hasMother[.Female]SpecificValue: P.{x} hasValue hasColleague.{Matthew}Local reflexivity: -- hasSelfNarcisist  Person  hasSelf(loves)Keys -- hasKeyhasKey(Person, passportNumber, country)Subclass C1  C2 subClassOf Human  Animal  BipedEquivalence C1  C2 equivalentClass Man  Human  MaleDisjointness C1  C2   disjointWith, AllDisjointClasses Male  Female  DisjointUnion C  C1  ...  Cn and Ci Cj   foralli≠jdisjointUnionOf Person DisjointUnionOf (Man, Woman)Metaclasses and annotations on axioms are also valid in OWL2, and declarations of classes have to provided.Full list available in reference specs and in the Quick Reference Guide: http://www.w3.org/2007/OWL/refcard

OWL: Most common constructorsSubproperty P1  P2 subPropertyOf hasDaughter  hasChildEquivalence P1  P2 equivalentProperty cost  priceDisjointProperties P1  ...  Pn   disjointObjectProperties hasDaughter  hasSon  Inverse P1  P2- inverseOf hasChild  hasParent-Transitive P+  P TransitiveProperty ancestor+  ancestorFunctional   1P FunctionalProperty T  1hasMotherInverseFunctional   1P- InverseFunctionalProperty T  1hasPassportID-Reflexive ReflexivePropertyIrreflexive IrreflexivePropertyAsymmetric AsymmetricPropertyProperty chains P  P1 o ... o Pn propertyChainAxiom hasUncle  hasFather o hasBrotherEquivalence {x1}  {x2} sameIndividualAs {oeg:OscarCorcho}{img:Oscar}Different {x1}  {x2} differentFrom, AllDifferent {john}  {peter}NegativePropertyAssertion NegativeDataPropertyAssertion {hasAge john 35}NegativeObjectPropertyAssertion {hasChild john peter}Besides, top and bottom object and datatype properties exist

Basic Inference TasksSubsumption – check knowledge is correct (captures intuitions)Does C subsume D w.r.t. ontology O? (in every modelI of O, CIDI )Equivalence – check knowledge is minimally redundant (no unintended synonyms)Is C equivalent to D w.r.t. O? (in every modelI of O, CI = DI )Consistency – check knowledge is meaningful (classes can have instances)Is C satisfiable w.r.t. O? (there exists some modelI of O s.t. CI)Instantiation and queryingIs x an instance of C w.r.t. O? (in every modelI of O, xICI )Is (x,y) an instance of R w.r.t. O? (in every modelI of O, (xI,yI) RI )All reducible to KB satisfiability or concept satisfiability w.r.t. a KBCan be decided using highly optimised tableaux reasoners

MainReferences W3C OWL Working Group (2009) OWL2 Web Ontology Language Document Overview. http://www.w3.org/TR/2009/REC-owl2-overview-20091027/ Dean M, Schreiber G (2004) OWL Web Ontology Language Reference. W3C Recommendation. http://www.w3.org/TR/owl-ref/Gómez-Pérez, A.; Fernández-López, M.; Corcho, O. Ontological Engineering. Springer Verlag. 2003 Capítulo 4: Ontology languagesBaader F, McGuinness D, Nardi D, Patel-Schneider P (2003) The Description Logic Handbook: Theory, implementation and applications. Cambridge University Press, Cambridge, United KingdomJena web site:http://jena.sourceforge.net/Jena API: http://jena.sourceforge.net/tutorial/RDF_API/Jena tutorials:http://www.ibm.com/developerworks/xml/library/j-jena/index.htmlhttp://www.xml.com/pub/a/2001/05/23/jena.htmlPellet: http://clarkparsia.com/pellet RACER: http://www.racer-systems.com/FaCT++: http://owl.man.ac.uk/factplusplus/HermIT: http://hermit-reasoner.com/

MethodologicalguidelinesforLinked Data publicationMotivationRelated WorkGeoLinkedDataIdentification of the data sourcesVocabulary DevelopmentGeneration of the RDF dataPublication of the RDF dataData cleansingLinking the RDF dataEnable effective discoveryFuture Work

GeoLinkedDataIt is an open initiative whose aim is to enrich the Web of Data with Spanish geospatial data.This initiative has started off by publishing diverse information sources, such as National Geographic Institute of Spain (IGN-E) and National Statistics Institute (INE)http://geo.linkeddata.es

Motivation 99.171 % English 0.019 % SpanishThe Web of Data ismainlyforEnglishspeakersPoorpresence of SpanishSource:Billion Triples dataset at http://km.aifb.kit.edu/projects/btc-2010/Thanks to Aidan and Richard

Impact of Geo.linkeddata.esNúmero de tripletas en Español (July): 1.412.248 Número de tripletas en Español (End august): 21.463.088127Asunción Gómez Pérez

Processfor Publishing Linked Data onthe WebIdentificationof the data sourcesVocabularydevelopmentGenerationof the RDF DataPublicationof the RDF data Data cleansingLinking the RDF dataEnable effective discovery

1. Identification and selection of the data sourcesIdentificationof the data sourcesInstituto GeográficoNacionalVocabularydevelopmentGenerationof the RDF DataPublicationof the RDF data Data cleansingLinking the RDF dataInstituto Nacionalde EstadísticaEnable effective discovery

1. Identification and selection of the data sourcesInstituto Geográfico Nacional (GeographicSpanishInstitute)Multilingual (Spanish, Vasc, Gallician, Catalan)ConceptualizationmistmatchesGranularity (scale concept)Textual informationParticularatiesLongitudelatitudeInstituto Nacional de Estadística (StatisticSpanishInstitute)

ParticularatiesGeo (textual level)Temporal130Asunción Gómez Pérez

1. Identification and selection of the data sourcesIGN-E

1. Identification and selection of the data sourcesIndustryProductionIndexYearProvince

2. Vocabulary developmenthttp://www4.wiwiss.fu-berlin.de/bizer/pub/LinkedDataTutorial/#whichvocabsIdentificationof the data sourcesVocabularydevelopmentGenerationof the RDF DataThisisnotenoughPublicationof the RDF data Data cleansingLinking the RDF dataEnable effective discovery

2. VocabularydevelopmentFeaturesLightweight : Taxonomies and a fewpropertiesConsensuatedvocabulariesToavoidthemappingproblemsMultilingualLinked data are multilingualTheNeOnmethodology can helptoRe-enginer Non ontologicalresourcesintoontologiesPros: use domainterminologyalreadyconsensuatedbydomainexpertsWithdraw in heavyweightontologiesthosefeaturesthatyoudon’tneedReuseexistingvocabularies134Identificationof the data sourcesVocabularydevelopmentGenerationof the RDF DataPublicationof the RDF data Data cleansingLinking the RDF dataEnable effective discoveryAsunción Gómez Pérez

Knowledge ResourcesOntological ResourcesO. Design Patterns34O. Repositories and Registries56FlogicRDF(S)OWLOntologicalResourceReuse O. Aligning O. Merging562Ontology DesignPattern ReuseNon Ontological ResourceReuse436Non Ontological Resources2Ontological ResourceReengineering7GlossariesDictionariesLexicons5Non Ontological ResourceReengineering46ClassificationSchemasThesauriTaxonomiesAlignments2RDF(S)1FlogicO. ConceptualizationO. ImplementationO. FormalizationO. SpecificationSchedulingOWL8Ontology Restructuring(Pruning, Extension, Specialization, Modularization)9O. Localization1,2,3,4,5,6,7,8, 9Ontology Support Activities: Knowledge Acquisition (Elicitation); Documentation; Configuration Management; Evaluation (V&V); Assessment135

Vocabularydevelopment: SpecificationContent requirements: Identifythe set of questionsthattheontologyshouldanswerWhichone are theprovinces in Spain?Where are thebeaches?Where are thereservoirs?Identifytheproductionindex in MadridWhichoneisthecitywithhigherproductionindex?Give me Madrid latitude and altitude….Non-contentrequirementsTheontologymustbe in thefourofficialSpanishlanguages136Asunción Gómez Pérez

2. Lightweight Ontology DevelopmentWGS84 Geo Positioning: an RDF vocabularyscv:Dimensionscv:Itemscv:Datasethydrographical phenomena (rivers, lakes, etc.)Vocabulary for instants, intervals, durations, etc.Names and international code systems for territories and groupsOntology for OGC Geography Markup Language reusedFollowing the INSPIRE (INfrastructure for SPatial InfoRmation in Europe) recommendation.hydrOntology,SCOVO, FAO Geopolitcal, WGS84, GML, and Time

Objetivos:INSPIRE intenta conseguir fuentes armonizadas de Información Geográfica para dar soporte a la formulación, implementación y evaluación de políticas comunitarias (Medio Ambiente, etc).Fuentes de Información Geográfica: Bases de datos de los Estados Miembros (UE) a nivel local, regional, nacional e internacional.Contexto – Directiva INSPIRE Luis Manuel Vilches Blázquez

INSPIRE - AnexosLuis Manuel Vilches Blázquez

hydrOntologyExistencia de gran diversidad de problemas (múltiples fuentes, heterogeneidad de contenido y estructuración, ambigüedad del lenguaje natural, etc.) en la información geográfica.Necesidad de un modelo compartido para solventar los problemas de armonización y estructuración de la información hidrográfica.hydrOntology es una ontología global de dominio desarrollada conforme a un acercamiento top-down. Recubrir la mayoría de los fenómenos representables cartográficamente asociados al dominio hidrográfico.Servir como marco de armonización entre los diferentes productores de información geo-espacial en el entorno nacional e internacional.Comenzar con los pasos necesarios para obtener una mejor organización y gestión de la información geográfica (hidrográfica).Luis Manuel Vilches Blázquez

FuentesTesauros y BibliografíaCatálogos de fenómenosGettyFTT ADLBCN25GEMETWFDCC.AA.EGM & ERMDiccionarios yMonografíasBCN200Nomenclátor Geográfico NacionalNomenclátor ConcisoLuis Manuel Vilches Blázquez

Criterios de estructuración Directiva Marco del AguaPropuesta por Parlamento y Consejo de la UELista de definiciones de fenómenos hidrográficosProyecto SDIGERProyecto piloto INSPIREDos cuencas, países e idiomasCriterios semánticosDiccionarios geográficosDiccionario de la Real Academia de la LenguaWordNetWikipediaBibliografía de varias áreas de conocimientoHerencia: Estructuración actual de catálogosAsesoramiento expertos en toponimia del IGNLuis Manuel Vilches Blázquez

Modelización del dominio hidrográfico Luis Manuel Vilches Blázquez

Implementación & Formalizacón+ Pellet41253+150 conceptos (classes) , 47 tipos de relaciones (properties) y 64 tipos de atributos (attribute types)Luis Manuel Vilches Blázquez

2. Vocabularydevelopment: HydrOntology145Asunción Gómez Pérez

3. Generation of RDFFrom the Data sourcesGeographic information (Databases)Statistic information (.xsl)Geospatial information Different technologies for RDF generationReengineering patternsR20 and ODEMapsterAnnotation toolsGeometry generationIdentificationof the data sourcesVocabularydevelopmentGenerationof the RDF DataPublicationof the RDF data Data cleansingLinking the RDF dataEnable effective discovery

3. Generation of the RDF DataNOR2OINEODEMapsterIGNGeometry2RDFGeospatialcolumnIGN

3. Generation of the RDF Data / instances NOR2O is a software librarythatimplementsthetransformationsproposedbythePatternsfor Re-engineering Non-OntologicalResources (PR-NOR). Currentlywehave 16 PR-NORs.PR-NORs define a procedurethattransforms a Non-OntologicalResource (NOR) componentsintoontologyelements. http://ontologydesignpatterns.org/· ClassificationschemesNOR2O· Thesauri· LexiconsNOR2OFAO Water classification· Classification scheme· Path enumeration data model· Implemented in a database

Re-engineeringModelforNORsPatterns for Re-engineeringNon-Ontological Resources (PR-NOR)Ontology Forward Engineering Con-ceptualSpeci-ficationNOR Reverse EngineeringConceptua-lizationTransformationRequirementsFormalizationDesignImplementationImplementationRDF(S)Non-Ontological ResourceOntology

PR-NOR library at the ODP PortalTechnologicalsupporthttp://ontologydesignpatterns.org/wiki/Submissions:ReengineeringODPs

3. Generation of the RDF Data – NOR2ONOR2OYearIndustry Production IndexProvince

hydrOntology & Bases de DatosNGN1:25.000multilingüe© Migración de datos a la Web de los Datos - Enfoques, técnicas y herramientasLuis Manuel Vilches Blázquez

3. Generation of the RDF Data – R2O & ODEMapsterCreation of the R2O Mappings

3. Generation of the RDF Data – Geometry2RDFOracle STO UTIL package SELECT TO_CHAR(SDO_UTIL.TO_GML311GEOMETRY(geometry)) AS Gml311GeometryFROM "BCN200"."BCN200_0301L_RIO" cWHERE c.Etiqueta='Arroyo'

3. Generation of the RDF Data – Geometry2RDF

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