Presented to – Presented by-
Mr. Shreyaskar Gaur Pallavi Srivastava
Assistant Professor B.Tech(C.S.E)
Department of Computer Science & Semester-6
Technology
Roll no.- 0928210035
JPIET
Contents
W3C
Semantic web
Semantic web themes
Technology map
Applications
Advantages and disadvantages
Future scope
Imaginative aspect
W3C
International consortium directed by Tim Berners-Lee
Mission: “Lead the Web to its full potential”
Hosts: MIT, ERCIM, Keio University
Defines Web Standards
HTML, CSS, XML, Security
Web Accessibility Initiative (WAI)
Web Services (SOAP, WSDL, etc.)
Semantic Web
Method
Technical specifications developed with Working Groups and
extensive public review
Advanced Development to chart long term architectural
directions
W3C track record: building infrastructure to address
technical and social needs of the Web
Semantic web
“The Semantic Web is a major research initiative of the World Wide
Web Consortium (W3C) to create a metadata-rich Web of resources
that can describe themselves not only by how they should be
displayed (HTML) or syntactically (XML), but also by the meaning of the
metadata.”
From W3C Semantic Web Activity Page
“The Semantic Web is an extension of the current web in which
information is given well-defined meaning, better enabling computers
and people to work in cooperation.”
Tim Berners-Lee, James Hendler, Ora Lassila,
The Semantic Web, Scientific American, May 2001
Semantic Web
Data Integration at Web Scale
Web of data
framework for integrating multiple sources
to draw new conclusions
architecture for describing all kinds of things
(items, collections, services, processes, etc.)
Increase the utility of information by
connecting it to its definitions and its
context
effective management and reuse of data at
various scales (personal, group, enterprise,
community, web
Today, the W3C positions the Semantic Web into a number
of areas:
Semantic web themes
Linked data
Data on the Web should be available in a standard format.
Relationships among data should be made available, too, to create a Web of Data .
Collection of interrelated datasets on the Web.
Vocabulary-
Concepts and relationships (also referred to as “terms”) used to describe and
represent an area of concern.
Used to-
Classify the terms that can be used in a particular application.
Characterize possible relationships.
Define possible constraints on using those terms.
The role are to help data integration.
E.g. a:author same as f:auteur
Query
Programmatic mechanisms to retrieve all the data.
Semantic web themes
Inference
* Automatic procedures can generate new
relationships.
* Used for data integration on the Web, by-
* discovering new relationships
* automatically analyzing the content of the
data
* managing knowledge on the Web .
Vertical applications
Used to explore how Semantic Web technologies
can help improve operations, efficiencies, and
provide better user experiences.
The two most prominent areas for Semantic
Web adoption are
Health Care/Life Sciences
e-Government sectors
Data Integration in Semantic web
1. Map the various data onto an abstract data representation
make the data independent of its internal representation
2. Merge the resulting representations
3. Start making queries on the whole!
queries that could not have been done on the individual data
sets
RDF
RDF(Resource Description Framework) is the first and the fundamental technology of
semantic web.
It describes Resources through a series of Statements.
RDF has following important concepts
• Resource : The resources being described by RDF are anything that can be named via a
URI.
• Property : A property is also a resource that has a name, for instance Author or Title.
• Statement : A statement consists of the combination of a Resource, a Property, and
an associated value.
Each statement is a Property and Value that is about a Resource.
An RDF Triple (s,p,o) is such that:
“s”, “p” are URI-s, ie, resources on the Web; “o” is a URI or a literal
“s”, “p”, and “o” stand for “subject”, “property”, and “object
Resources can use any URI, e.g.:
http://www.example.org/file.xml#element(home)
http://www.example.org/file2.xml#xpath1(//q[@a=b])
URI-s can also denote non Web entities:
http://www.ivan-herman.net/me is me
not my home page, not my publication list, but me
RDF & RDFS
Another significant part of RDF is it’s
Schema language. RDF Schema allows for
greater specification of semantics for
information models.
RDFS defines resources and classes:
everything in RDF is a “resource”
“classes” are also resources, but…
…they are also a collection of possible
resources (i.e., “individuals”)
“fiction”, “novel”
Relationships are defined among classes <rdf:Description
and resources: rdf:about="http://…/isbn/202038
6682">
“typing”: an individual belongs to a specific <f:titre xml:lang="fr">Le
class palais des mirroirs</f:titre>
“«The Glass Palace» is a novel” <f:original
to be more precise: rdf:resource="http://…/isbn/000
“«http://.../000651409X» is a novel” 651409X"/>
“sub classing”: all instances of one are also </rdf:Description>
the instances of the other (“every novel is a
fiction”)
RDFS formalizes these notions in RDF
RDF example
Has road
Garden st. In Suburb
Intersection
In location Has road
Central
ave
In Suburb
Traffic Sydney
accident Eveleigh
In city
OWL
Declarative knowledge representation
language for the Semantic Web with
formally defined meaning for creating
ontologies.
It is a ‘Monotonic’ language.
Collection of basic “pieces of knowledge.”
Statements that are made in an ontology are
called axioms in OWL.
The ontology asserts that its axioms are true.
OWL denotes:
• objects as individuals,
• categories as classes, and
• relations as properties.
SPARQL
SPARQL query language and the accompanying
semantics and protocols makes possible to send PREFIX ns: <http://road.com/>
queries and receive results . SELECT ?name
WHERE
SPARQL queries are similar in syntax to SQL
{
based on the RDF triple models ?road ns:inSuburb “Eveleigh”
provide patterns against such relationships in which .
some resource references are variables.
?road ns:hasName ?name .
A SPARQL engine would return the resources that }
match these patterns for all triples.
Under current development are a The results would be:
SPARQL Update language Name
SPARQL HTTP bindings “Garden St”
discovery mechanism for describing the capabilities of a “Central Ave”
SPARQL endpoint.
GRDDL & POWDER
GRDDL
* GRDDL is a mechanism for Gleaning Resource Descriptions from Dialects of Languages.
* introduces markup based on existing standards for:
* declaring that an XML document includes data compatible with the RDF
* linking to algorithms (typically represented in XSLT),
* extracting this data from the document.
POWDER ( Protocol for Web Description Resources )
Supports
the provision of description resources
way to apply them to groups of online resources
the authentication of those descriptions .
There are two versions of POWDER:
one simple version expressed in XML.
the other that harnesses the Semantic Web languages (POWDER-S).
SKOS
An area of work developing specifications and standards to support the use of knowledge
organization systems (KOS) such as thesauri, classification schemes, subject heading lists and
taxonomies within the framework of the Semantic Web
Rule Interchange Format
Family of specifications which focuses on exchange rather
than a single one-fits-all rule language but even rule
exchange alone is a complex and daunting area.
Rule systems fall into three categories;
first-order
logic-programming
action rules
Family of languages, called dialects.
Core idea : Different rule systems will provide syntactic
mappings from their native languages to RIF dialects and back.
Mappings are required to be preserve their original
semantics
Tools
Categories
The following Semantic Web tools
have been recently released:
Inference
Triple Stores Converters AceWiki (Version 0.5.3, 19
engines
January 2012)
LDIF (Version 0.4, 16 January
Search 2012)
Middleware CMS
engines AllegroGraph (Version 4.4.0.1, 12
January 2012)
Semantic Semantic MediaWiki (Version
Development Semantic 1.7.0.1, 9 January 2012)
Web
environments Wikis
browsers Bigdata (Version 1.1.0, 20
December 2011)
Current news
Based in Los Angeles, Cognition Technologies has
developed innovative Semantic Natural Language
Processing (NLP) technology .
A leading biopharmaceutical company has chosen
Semantelli’s CoProtect software to manage its online
and social media reputation.
Semantic advertising web service ADmantX has
announced a partnership with adBrite, “the largest
independent ad exchange, to offer brand safety,
greater ad engagement and page-level, cookie-less
targeting to advertisers and publishers.
CitizenNet is using semantic analysis and natural
language processing to provide customers with
automatic social media promotion
Future Aspect
The semantic web is driving the evolution of current web by
enabling users to find ,share & combine information more easily.
The US government has propelled the adoption of semantic web
in governmental agencies.
More than 2,70,000 data sets are available for public viewing with
the help of Data Gov project.
At present , semantic web witnesses funding inflow for product
development.
In future, the investments are likely to be made in projects where
focus is on enhancing the existing ecosystems on internet
especially in :
Social computing
Search engines enhancements
Advertising
Analytical tools
Semantic innovations relevant to thriving ecosystems such as
Facebook & twitter stand better chance of attracting funds from
venture capalists & other funding agencies.
Clarabridge,which delivers highly customized enterprise
processing solutions had acquired $4.33 million for marketing &
sales expansion.
Semantic web is about an individual.
Searches: With semantic search engines we can receive
right information/content at the right time from
anywhere.
Once the Semantic Web exists, it can provide the ability
to tag all content on the Web, describe what each piece
of information is about and give semantic meaning to
the content item.
Thus, search engines become more effective than they
are now, and users can find the precise information
they are hunting.
E-commerce : “We believe this is what you are looking”
Online ad: “Personalized ad display based on user
preferences, community and other characteristics”.