Post on 11-May-2015
description
Agenda
• World Wide Web
• Semantic Web
• Semantic Web Tools and Applications
• Linking Open Data
• Social Semantic Web
• Open Government
Agenda
World Wide Web
• Semantic Web
• Semantic Web Tools and Applications
• Linking Open Data
• Social Semantic Web
• Open Government
World Wide Web
a system of interlinked hypertext documents accessed via the Internet
Web Architecture
Document
Identifier Protocol
URI HTTP
HTML
an application protocol for
distributed, collaborative,
hypermedia information systems
a string of characters
used to identify a name
or a resource
the main markup language for
displaying web pages and other
information that can be displayed
in an web browser
HTML is used
to display web pages
for human.
<a href="http://en.wikipedia.org/wiki/Html">
HTML
</a>
<a href="http://en.wikipedia.org/wiki/World_Wide_Web">
Web
</a>
hyperlink
hyperlink
Hyperlink in HTML is
a reference to document.
What is problem?
Cars.com AutoTrader.com
same
information,
but …
How to use it for machine as data?
Agenda
• World Wide Web
Semantic Web
• Semantic Web Tools and Applications
• Linking Open Data
• Social Semantic Web
• Open Government
providing a common framework that allows data to be shared and
reused across application, enterprise, and community boundaries
A6
Car
Gasoline
3.0L V6
24V GDI
8-Speed
Automatic Sedan
4
AWD
115”
type
transmission
wheelbase
engine
fuel
drivetrain
doors
body_style
Basic Concept for Data Description
on the Semantic Web
Semantic Web Layer Cake
URI (Uniform Resource Identifier)
a string of characters used to identify a name or a resource
URN (Uniform Resource Name)
URL (Uniform Resource Locator) +
URI
urn:isbn:0451450523
urn:isan:0000-0000-9E59-0000-O-0000-0000-2
urn:issn:0167-6423
ftp://asmith@ftp.example.org
http://en.example.org/wiki/url
to be used as a general method for conceptual description or
modeling of information that is implemented in web resources, using a
variety of syntax formats
http://www.cars.com/car#A6
http://www.cars.com/car#Car
http://www.cars.com/car#Gasoline
http://www.cars.com/car#GDI
http://www.cars.com/car#Auto_8-Speed http://www.cars.com/car#Sedan
4
http://www.cars.com/car#AWD
115”
http://www.w3.org/1999/02/22-rdf-syntax-ns#type
http://www.cars.com/car#transmission
http://www.cars.com/car#wheelbase
http://www.cars.com/car#engine
http://www.cars.com/car#fuel
http://www.cars.com/car#drivetrain
http://www.cars.com/car#doors
http://www.cars.com/car#body_style
RDF Example
XML (Extensible Markup Language)
a markup language that defines a set of rules for encoding
documents in a format that is both human-readable and machine-
readable
<?xml version="1.0" encoding="utf-8"?>
<note>
<to>Tove</to>
<from>Jani</from>
<heading>Reminder</heading>
<body>Don't forget me this weekend!</body>
</note>
RDF/XML
an XML syntax for writing down and exchanging RDF graphs,
called RDF/XML
<?xml version="1.0"?>
<!DOCTYPE rdf:RDF [<!ENTITY xsd "http://www.w3.org/2001/XMLSchema#">]>
<rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
xmlns:car="http://www.cars.com/car#"
xml:base="http://www.cars.com/car">
<rdf:Description rdf:ID="A6">
<rdf:type rdf:resource="Car" />
<car:engine rdf:resource="GDI" />
<car:body_style rdf:resource="Sedan" />
<car:doors rdf:datatype="&xsd;int">4</car:doors>
...
</rdf:Description>
...
</rdf:RDF>
RDFS (RDF Schema)
a set of classes with certain properties using the RDF extensible
knowledge representation language, providing basic elements
for the description of ontologies, otherwise called RDF vocabularies,
intended to structure RDF resources
car:Car
car:Vehicle
rdfs:subClassOf
rdf:Property
car:body_style rdfs:domain
rdfs:range
rdfs:Class
rdf:type
rdf:type
car:Style
rdf:type
car:A6
rdf:type
car:Sedan rdf:type car:body_style
TBox - terminological component
ABox - assertion component
Ontology
knowledge representation as a set of concepts within a domain, and
the relationships between those concepts
formal, explicit specification of a shared conceptualisation
"Ontologies are often equated with taxonomic hierarchies of
classes, class definitions, and the subsumption relation, but
ontologies need not be limited to these forms. Ontologies are
also not limited to conservative definitions — that is,
definitions in the traditional logic sense that only introduce
terminology and do not add any knowledge about the world.
To specify a conceptualization, one needs to state axioms
that do constrain the possible interpretations for the defined
terms."
OWL (Web Ontology Language)
a family of knowledge representation languages for authoring
ontologies on the Semantic Web
Semantics of RDF, RDFS, and OWL
Each language for the Semantic Web provides a formal meaning
based on a model-theoretic semantics in its abstract syntax.
<x, y> is in IEXT(I(rdfs:subClassOf))
if and only if x and y are in IC
and ICEXT(x) is a subset of ICEXT(y)
car:Car
car:Vehicle
rdfs:subClassOf
car:A6
rdf:type
rdf:type
Language for the Rule Description
SWRL (Semantic Web Rule Language) is a proposal for a Semantic
Web rules-language, combining sublanguages of the OWL Web Ontology
Language (OWL DL and Lite) with those of the Rule Markup Language
(Unary/Binary Datalog).
<ruleml:imp>
<ruleml:_rlab ruleml:href="#example1"/>
<ruleml:_body>
<swrlx:individualPropertyAtom swrlx:property="hasParent">
<ruleml:var>x1</ruleml:var> <ruleml:var>x2</ruleml:var>
</swrlx:individualPropertyAtom>
<swrlx:individualPropertyAtom swrlx:property="hasBrother">
<ruleml:var>x2</ruleml:var> <ruleml:var>x3</ruleml:var>
</swrlx:individualPropertyAtom>
</ruleml:_body>
<ruleml:_head>
<swrlx:individualPropertyAtom swrlx:property="hasUncle">
<ruleml:var>x1</ruleml:var> <ruleml:var>x3</ruleml:var>
</swrlx:individualPropertyAtom>
</ruleml:_head>
</ruleml:imp>
hasParent(?x1,?x2) ∧ hasBrother(?x2,?x3) ⇒ hasUncle(?x1,?x3)
Inference
being able to derive new data from data that you already know
hasParent hasParent
hasWife
if hasParent(?x, ?y)
hasParent(?x, ?z)
Man(?y)
Woman(?z)
then hasWife(?y, ?z)
SPARQL
an RDF query language, that is able to retrieve and manipulate data
stored in Resource Description Framework format
PREFIX foaf: <http://xmlns.com/foaf/0.1/>
SELECT ?name ?email
WHERE {
?person a foaf:Person.
?person foaf:name ?name.
?person foaf:mbox ?email.
}
Agenda
• World Wide Web
• Semantic Web
Semantic Web Tools and Applications
• Linking Open Data
• Social Semantic Web
• Open Government
Ontology Editor
Protégé
a free, open source ontology editor and knowledge-base framework
TopBraid Composer
a visual modeling environment from industry experts for creating and
managing domain models and ontologies in the Semantic Web standards
RDF, RDFS and OWL
OntoStudio
a professional developing environment of ontologies for ontologies and
rules with components for the integration of heterogeneous data sources
tools that provide complex development environments for Semantic Web applications, going
beyond a simple library for a programming language
TopBraid Composer
Class Panel Property Panel Editing Panel
Programming Environment
for the Semantic Web
Jena
a Java framework to construct Semantic Web Applications for RDF, RDFS
and OWL, SPARQL, GRDDL
OWL API
a Java interface and implementation for the W3C Web Ontology Language
OWL
Sesame
an open source RDF database with support for RDFS inferencing and
querying
tools that provide a working environment to develop Semantic Web applications in the forms
of application libraries, modules, etc
Jena
Triple Store
Jena
TDB which provides a lightweight, scalable non-transactional storage and
SDB which is a SPARQL database subsystem for Jena
OpenLink Virtuoso
a SQL-ORDBMS and Web Application Server hybrid (aka Universal Sever)
that provides SQL, XML, and RDF data management in a single
multithreaded server process
Oracle Spatial 11g
an open, scalable, secure and reliable RDF management platform based
on a graph data model
OWLIM
the most scalable semantic repository that includes triple store, inference
engine and SPARQL query engine
tools that can be installed to serve as RDF databases
OpenLink Virtuoso
SPARQL Endpoint tools that can be serve as SPARQL endpoints to large data sets
OpenLink Virtuoso
the Virtuoso SPARQL query service that implements the SPARQL Protocol
for RDF providing SPARQL query processing
Online Demo: http://demo.openlinksw.com/sparql/
Pubby
a Linked Data interface to local or remote SPARQL protocol servers
Most of triple stores support a interface for SPARQL.
Reasoner tools that can perform reasoning tasks, typically based on RDFS, OWL, or some rule engine
Jena, OWL API, OpenLink Virtuoso, Pellet, …
Most of programing environments and triple stores support reasoning
based on RDF, RDFS, and OWL semantics and rule.
RDB2RDF tools can be used to extract RDF data from a Relational Database, using either RDB2RDF
Direct Mapping or R2RML
D2RQ
a system for accessing relational databases as virtual, read-only RDF
graphs
Sponger
the Linked Data middleware component of Virtuoso that generates Linked
Data from a variety of data sources, supporting a wide variety of data
representation and serialization formats
online search engines specialized in OWL and/or RDF content, possibly including ontologies and vocabularies
Swoogle
a search engine for Semantic Web ontologies, documents, terms
and data published on the Web
Watson
web interface for searching ontologies and semantic documents using keywords
Naver Semantic Movie Search
Apple’s Siri
an intelligent personal assistant and knowledge navigator
which works as an application for Apple's iOS
a natural language user interface to answer questions, make
recommendations, and perform actions by delegating requests to a set of
Web services
How Siri Works Siri’s knowledge is
represented in a unified
modeling system that
combines ontologies,
inference networks, pattern
matching agents, dictionaries,
and dialog models. ... Siri isn’t
a source of data, so it doesn’t
expose data using Semantic
Web standards.
Google’s Semantic Search
They decided to call it
“Knowledge Graph”.
Knowledge Graph
a knowledge base used by Google to enhance its search engine's search
results with semantic-search information gathered from a wide
variety of sources
Agenda
• World Wide Web
• Semantic Web
• Semantic Web Tools and Applications
Linking Open Data
• Social Semantic Web
• Open Government
Linking Open Data
a method of publishing structured data to share information in a
way that can be read automatically by computers based on standard Web
technologies such as HTTP and URIs
Components for LOD
• URIs (specifically, of the dereferenceable variety)
• HTTP
• Resource Description Framework (RDF)
• Serialization formats (RDFa, RDF/XML, N3, Turtle, and others)
Four Principles of Linked Data
1. Use URIs to identify things.
2. Use HTTP URIs so that these things can be referred to and looked up
("dereferenced") by people and user agents.
3. Provide useful information about the thing when its URI is
dereferenced, using standard formats such as RDF/XML.
4. Include links to other, related URIs in the exposed data to improve
discovery of other related information on the Web.
Linked Open Data star scheme
★ make your stuff available on the Web
(whatever format) under an open license
★★ make it available as structured data
(e.g., Excel instead of image scan of a table)
★★★ use non-proprietary formats
(e.g., CSV instead of Excel)
★★★★ use URIs to identify things, so that people can
point at your stuff
★★★★★ link your data to other data to provide context
http://lab.linkeddata.deri.ie/2010/star-scheme-by-example/
2007-11-10 2008-09-18
2009-07-14
2010-09-22
2011-09-19
DBPedia
a project aiming to extract structured content from the information
created as part of the Wikipedia project using the Resource
Description Framework (RDF) to represent the extracted
information
more than 3.64 million things, out of which 1.83 million are classified in
a consistent ontology
2,724,000 links to images and 6,300,000 links to external web pages
over 1 billion pieces of information (RDF triples)
Freebase
a large collaborative knowledge base consisting of metadata
composed mainly by its community members
Linked Data on BBC
Data from Wikipedia
Data from MusicBrainz
Best Buy with GoodRelations
<div class="vcard" typeof="gr:LocationOfSalesOrServiceProvisioning" about="#store_1796">
<div class="hours" rel="gr:hasOpeningHoursSpecification">
<li class="day0" typeof="gr:OpeningHoursSpecification" about="#storehours_sun">
<span rel="gr:hasOpeningHoursDayOfWeek" resource="http://purl.org/goodrelations/v1#Sunday" class="day">
<span property="gr:opens" datatype="xsd:time" content="11:00:00" class="open">
...
Agenda
• World Wide Web
• Semantic Web
• Semantic Web Tools and Applications
• Linking Open Data
Social Semantic Web
• Open Government
Social Semantic Web
a Web of collective knowledge
systems, which are able to provide
useful information based on
human contributions and which
get better as more people
participate
Syntax Semantic
World Wide Web URIs, HTML, HTTP
Semantic Web RDFS, OWL, SPARQL
Social Web Wikis, blogs, social networks
Social
Semantic Web SIOC, DBpedia, Twine
Vocabularies for SSW
FOAF (Friend of a friend)
a phrase used to refer to someone that one does not know well, literally, a
friend of a friend
SIOC (Semantically-Interlinked Online Communities)
methods for interconnecting discussion methods such as blogs, forums
and mailing lists to each other
SKOS (Simple Knowledge Organization System)
formal languages designed for representation of thesauri, classification
schemes, taxonomies, subject-heading systems, or any other type of
structured controlled vocabulary
MOAT (Meaning Of A Tag)
a Semantic Web framework to publish semantically-enriched content from
free-tagging one
Facebook’s Open Graph Protocol
simple protocol for enabling any web page to become a rich object in a social graph
Myungjin Lee
is a friend of
is a friend of
is a friend of
is a friend of
like
watch
watch
cook
like
In 2010, we extended the social graph, via the
Open Graph protocol, to include 3rd party web
sites and pages that people liked throughout
the web. We are now extending the Open Graph
to include arbitrary actions and objects created
by 3rd party apps and enabling these apps to
integrate deeply into the Facebook experience.
Myungjin Lee
cook
http://example.com/cookie.html
Social Object
http://www.facebook.com/mjinlee
http://example.com/cookie.html
http://samples.ogp.me/Recipe
Stuffed Cookies
me:cook rdf:type
http://example.com/zhen/cookie.jpg
The Turducken of Cookies
http://example.com/zhen/cookie.html
og:title
og:image
og:description og:url
Twitter Annotations
to add one or more annotations that represent structured metadata
about the tweet
How to make Annotations on your tweets
First element is a type.
Every Annotations has a type.
Type maps to attribute and value pair.
Second element is one or more attribute names with values.
http://r.github.com/annotationsformatter/
Agenda
• World Wide Web
• Semantic Web
• Semantic Web Tools and Applications
• Linking Open Data
• Social Semantic Web
Open Government
Open Government Data
By “open”, “open” data is free for
anyone to use, re-use and re-
distribute.
By “government data” we mean data
and information produced or
commissioned by government or
government controlled entities.
Open
Gov Data
Open
Data
Open
Gov
Data
Gov
Open
Gov
Data
Publishing Open Government Data
Step 1: The quickest and easiest way to make data available on the
Internet is to publish the data in its raw form (e.g., an XML file of polling
data from past elections). However, the data should be well-structured like
XML, RDF and CSV.
Step 2: Create an online catalog of the raw data so people can discover
what has been posted.
Step 3: Make the data both human- and machine-readable:
• enrich your resources with semantics, metadata, and identifiers;
• encode the data using open and industry standards - especially XML
- or create your own standards based on your vocabulary;
• make your data human-readable by either converting to (X)HTML,
or by using real-time transformations through CSS or XSLT.
• use permanent patterned and/or discoverable "Cool URIs";
• allow for electronic citations in the form of standardized hyperlinks.
Data.gov (the United States Government)
Data.gov.uk (HM Government)
A Timeline of Open Government Data
Data-Gov Wiki
a project for investigating open government datasets using semantic web
technologies
http://data-gov.tw.rpi.edu/wiki/The_Data-gov_Wiki
Clean Air Status and Trends - Ozone
Code for America
a non-partisan, non-political 501(c)3 organization founded in
2009 to bring web-industry professionals to work with city governments
in the United States in order to promote openness, participation,
and efficiency in municipal governments
http://codeforamerica.org/
SolarCity
DataMarket
a privately held Icelandic company that specialises in providing access
to and visually displaying data from public and, to a lesser extent,
private institutions and companies
Conte
nts
Searc
h o
n th
e S
em
antic
Web
Dr. Myungjin Lee
e-Mail : xml@yonsei.ac.kr Twitter : http://twitter.com/MyungjinLee
Facebook : http://www.facebook.com/mjinlee SlideShare : http://www.slideshare.net/onlyjiny/
References http://www.w3.org/2001/sw/wiki/
http://www.wikipedia.org
http://www.slideshare.net/Cloud/the-social-semantic-web
http://www.slideshare.net/onlyjiny/social-semantic-web-on-facebook-open-graph-protocol-and-twitter-annotations
http://www.slideshare.net/onlyjiny/inference-on-the-semantic-web
http://www.novaspivack.com/technology/how-hisiri-works-interview-with-tom-gruber-cto-of-siri
http://linkeddata.org/
http://www.slideshare.net/HaklaeKim/open-government-data-linked-data-and-the-missing-blocks-in-korea
http://opengovernmentdata.org/