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Semantic Web PRESENTED BY: ANDRÉ MAZAYEV ANDRE.MAZ.90[AT]GMAIL[DOT]COM

Semantic web: An overview

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Page 1: Semantic web: An overview

Semantic Web

PRESENTED BY: ANDRÉ MAZAYEVA N D R E . M A Z . 9 0 [ AT ] G M A I L [ D O T ] C O M

Page 2: Semantic web: An overview

Semantic Web? Whaaat?◦ What semantic web means?

◦ Smarter web!! Duuuh!

Page 3: Semantic web: An overview

Semantic Web? Whaaat?◦ What semantic web means?

◦ Smarter web!! Duuuh!

◦ Ok. But more specifically?◦ It’s a web where it is easier to find stuff on internet

Page 4: Semantic web: An overview

Semantic Web? Whaaat?◦ What semantic web means?

◦ Smarter web!! Duuuh!

◦ Ok. But more specifically?◦ It’s a web where it is easier to find stuff on internet

◦ Yeah! But how?◦ Hmmmmm……

Page 5: Semantic web: An overview

Web 2.0◦ Search Process

◦ Refine search as you go

◦ The user is guiding the search accordingly to the results that are shown

◦ Search engine is only performing syntax based pattern match

◦ Plus some features to improve performance and accuracy

◦ Semantics are not used or used in a limited way during the search process

Page 6: Semantic web: An overview

Syntax and Semantics◦ Syntax

◦ About form

◦ Semantics◦ About meaning

Page 7: Semantic web: An overview

Syntax and Semantics◦ Syntax

◦ Green, Yellow, Red

◦ Semantics◦ Green = Go

◦ Yellow = Better stop

◦ Red = Stop

Traffic Light

Adapted from: Semantic Web from the 2013 Perspective

Page 8: Semantic web: An overview

User’s Web Example

Example of dumb web

◦ Goal◦ Find the telephone number of James Bond

Page 9: Semantic web: An overview

User’s Web Example

Example of dumb web

◦ Goal◦ Find the telephone number of James Bond

◦ For humans the answer is easy to find◦ James Bond’s telephone number is 1-800-555-0199

◦ James Bond is a fictional MI6 agent

◦ Since it’s a fictional agent we can infer that the number must be fake

Page 10: Semantic web: An overview

Machine’s Web Example

Example of dumb webSource code of dumb web

◦ For machines find Bond’s number is a hard task◦ No machine “readable” semantics

◦ Current Web◦ Created for document sharing

◦ Instead of data sharing

◦ Adapted for Human to Human

◦ Machine to Machine communication is difficult

Page 11: Semantic web: An overview

Smart vs Dumb Web

Example of dumb web

Example of smart web

Page 12: Semantic web: An overview

Smart vs Dumb WebVisually both pages are identical

Smart page carries much more “meaning”

Example of dumb web

Example of smart web

Page 13: Semantic web: An overview

Smart vs Dumb WebSource code of smart webSource code of dumb web

Page 14: Semantic web: An overview

Source code analysis

Contains more machine friendly structure◦ Vocabulary is defined

◦ Data is structured

◦ Data is enriched

The data can be represented as a graph

Source code of smart web

Page 15: Semantic web: An overview

James

Bond

1-800-555-0199

James Bond

typeof

name

telephone

Person

Source code analysisSource code of smart web

Page 16: Semantic web: An overview

James

Bond

1-800-555-0199

James Bond

typeof

name

telephone

Person

Source code analysis

With structured data it’s easy for a machine to find Bond’s telephone number

Source code of smart web

Page 17: Semantic web: An overview

Graph analysis

◦ Simple statements◦ Subject – Predicate – Object

◦ All elements have their own URL

◦ Data is structured

◦ Data can be explored by machinesJames

Bond

1-800-555-0199

James Bond

typeof

name

telephone

Person

URL

URL

URL

Page 18: Semantic web: An overview

Structured Data Tool

Source code of a page with semantic markup Extracted data

Page 19: Semantic web: An overview

Structured Data Tool

Extracted data

◦ Data recognized by Google’s web crawler

◦ With structured data answers are easy to get ◦ What?

◦ Where?

◦ When Open?

Page 20: Semantic web: An overview

Semantic WebPresent Future

Web of Documents Web of Data

Small Change

Big Difference

◦ Data is explicit

◦ Data is connected

◦ Data can be explored by machines◦ Nontrivial connections can be found

◦ Demo◦ RelFinder

Page 21: Semantic web: An overview

Semantic Building Blocks

Page 22: Semantic web: An overview

RDF

Page 23: Semantic web: An overview

RDF◦ Resource Description Framework

◦ Simple statements (triples)◦ Subject – Predicate – Object

◦ Building block of RDFS and OWL

◦ Multiple serialization formats◦ RDF/XML

◦ Turtle

◦ N-Triples

Bond example in Turtle

Page 24: Semantic web: An overview

RDFS

Page 25: Semantic web: An overview

RDFS◦ RDF Schema

◦ Limited expressivity

◦ Describes classes, subclasses and properties

◦ Primary focused on “is a” and “sub class of” relationships

Vocabulary

Canine

Animal Human

Mammal

Feline

Reptile

Taxonomy

Animal

MammalReptile

Human

Canine Feline

subClassOf subClassOf

subClassOf subClassOf

subClassOf

Page 26: Semantic web: An overview

SPARQL

Page 27: Semantic web: An overview

SPARQL◦ SPARQL Protocol And RDF Query Language

◦ SQL-Like structure

James

Bond

1-800-555-0199

James Bond

typeof

name

telephone

Person

Graph

Page 28: Semantic web: An overview

SPARQL◦ SPARQL Protocol And RDF Query Language

◦ SQL-Like structure

James

Bond

1-800-555-0199

James Bond

typeof

name

telephone

Person

Graph

Goal: Find Bond’s Number

Page 29: Semantic web: An overview

SPARQL◦ SPARQL Protocol And RDF Query Language

◦ SQL-Like structure

James

Bond

1-800-555-0199

James Bond

typeof

name

telephone

Person

Graph

Query

Goal: Find Bond’s Number

Page 30: Semantic web: An overview

SPARQL◦ SPARQL Protocol And RDF Query Language

◦ SQL-Like structure

James

Bond

1-800-555-0199

James Bond

typeof

name

telephone

Person

Graph

Answer

Query

Goal: Find Bond’s Number

Page 31: Semantic web: An overview

OWL

Page 32: Semantic web: An overview

OWL◦ Web Ontology Language

◦ Highly expressive◦ Brings expressivity of logic to Semantic Web

◦ More expressive than RDFS

◦ Allows to express◦ Constraints

◦ Cardinality

◦ Unions

◦ Intersections

◦ Etc.

Resource that has property hasParent with value Bond belongs to a class named BondChild

OWL Restriction

Note: Often the concepts of taxonomies and ontologies overlap and used to describe same thing

Page 33: Semantic web: An overview

SWRL

Page 34: Semantic web: An overview

SWRL◦ Semantic Web Rule Language

◦ Combines parts from OWL and Datalog

◦ Rule syntax◦ If body (antecedent) then assert head (consequent)

x3 is x1’s uncle

Page 35: Semantic web: An overview

Under Development◦ Pending questions

◦ How to ensure security of data?

◦ How to validate new data?

◦ Is source data reliable?

Page 36: Semantic web: An overview

Data Silos◦ Each application has its own

◦ Goals

◦ Vocabularies

◦ Knowledge base

◦ Not integrated with other data systems

◦ May have overlapping data

Application 1

Application 2

Application 3

Sensor

Network

Gateway

Server ApplicationData

Source

Relational

DB

Relational

DB

Page 37: Semantic web: An overview

Semantic Bridges

Sensor

Network

Gateway

ServerData

Source

Relational

DB

Relational

DB

RDB

Parser

CSV

Parser

WEB

Parser

RDF

InterfacesCombined RDF

Model

Combined

Knowledge Model

Application 1

Application 2

Application 3

Application

Sensor

Network

Gateway

ServerData

Source

Relational

DB

Relational

DB

RDB

Parser

CSV

Parser

WEB

Parser

RDF

InterfacesCombined RDF

Model

Combined

Knowledge Model

Application 1

Application 2

Application 3

Application

Sensor

Network

Gateway

ServerData

Source

Relational

DB

Relational

DB

RDB

Parser

CSV

Parser

WEB

Parser

RDF

InterfacesCombined RDF

Model

Combined

Knowledge Model

Application 1

Application 2

Application 3

Application

Sensor

Network

Gateway

ServerData

Source

Relational

DB

Relational

DB

RDB

Parser

CSV

Parser

WEB

Parser

RDF

InterfacesCombined RDF

Model

Combined

Knowledge Model

Application 1

Application 2

Application 3

Application

Page 38: Semantic web: An overview

Semantic Bridges

Sensor

Network

Gateway

ServerData

Source

Relational

DB

Relational

DB

RDB

Parser

CSV

Parser

WEB

Parser

RDF

InterfacesCombined RDF

Model

Combined

Knowledge Model

Zoom

Application 1

Application 2

Application 3

Application

Sensor

Network

Gateway

ServerData

Source

Relational

DB

Relational

DB

RDB

Parser

CSV

Parser

WEB

Parser

RDF

InterfacesCombined RDF

Model

Combined

Knowledge Model

Application 1

Application 2

Application 3

Application

Sensor

Network

Gateway

ServerData

Source

Relational

DB

Relational

DB

RDB

Parser

CSV

Parser

WEB

Parser

RDF

InterfacesCombined RDF

Model

Combined

Knowledge Model

Application 1

Application 2

Application 3

Application

Sensor

Network

Gateway

ServerData

Source

Relational

DB

Relational

DB

RDB

Parser

CSV

Parser

WEB

Parser

RDF

InterfacesCombined RDF

Model

Combined

Knowledge Model

Application 1

Application 2

Application 3

Application

Page 39: Semantic web: An overview

Data Integration

Data Sets

Combined RDF

Model

Combined

Knowledge Model

◦ Data from different sources is combined into a common model

◦ The whole is greater than the sum of its parts

◦ New knowledge can be obtained

Page 40: Semantic web: An overview

Data IntegrationAnimal

MammalReptile

Human

Canine Feline

subClassOf subClassOf

subClassOf subClassOf

subClassOf

Wolves Terriers

Hounds

subClassOf

subClassOf

subClassOf

Foundation

Ontology

Extended

Ontology

◦ Foundation ontologies transcend boundaries of single knowledge domain

◦ Common environment for◦ Different terminologies

◦ Different knowledge domains

◦ Makes data integration easier◦ Can be done (semi) automatically

◦ Easier to obtain new knowledge

Page 41: Semantic web: An overview

M3 Framework◦ Four data sources

◦ Different domains

◦ Overlapping data

◦ Same vocabulary

◦ Combined knowledge model

Adapted from: Machine-to-Machine Measurement (M3) Framework

Page 42: Semantic web: An overview

M3 Framework◦ Smart Band sends a set of

measurements about user

◦ One of the measurements is body temperature

Adapted from: Machine-to-Machine Measurement (M3) Framework

Page 43: Semantic web: An overview

M3 Graph View

Adapted from: Machine-to-Machine Measurement (M3) Framework

Page 44: Semantic web: An overview

M3 Framework◦ Naturopathy expert describes

lemon and it’s properties

◦ Lemon is good to treat cold

Adapted from: Machine-to-Machine Measurement (M3) Framework

Page 45: Semantic web: An overview

M3 Graph View

Adapted from: Machine-to-Machine Measurement (M3) Framework

Page 46: Semantic web: An overview

M3 Framework◦ Doctor describes High Fever as

symptom of Cold

◦ Given◦ Doctor’s info

◦ Lemon’s properties

◦ Framework can infer that◦ Lemon is good to treat High Fever

Adapted from: Machine-to-Machine Measurement (M3) Framework

Page 47: Semantic web: An overview

M3 Graph View

Adapted from: Machine-to-Machine Measurement (M3) Framework

Page 48: Semantic web: An overview

M3 Framework◦ User creates a rule:

◦ If body temperature is higher than 38

◦ Then user has High Fever

◦ Given◦ Sensor measurement

◦ User’s rule

◦ Doctor’s info

◦ Framework can infer that◦ User has Cold

Adapted from: Machine-to-Machine Measurement (M3) Framework

Page 49: Semantic web: An overview

M3 Graph View

Adapted from: Machine-to-Machine Measurement (M3) Framework

Page 50: Semantic web: An overview

M3 Framework◦ Given all the data

◦ Framework can recommend to the user a lemon tea to treat the cold

Adapted from: Machine-to-Machine Measurement (M3) Framework

Page 51: Semantic web: An overview

M3 Graph View

Adapted from: Machine-to-Machine Measurement (M3) Framework

Page 52: Semantic web: An overview

Linked Open World◦ Linked Open Data

◦ Data repositories (DataHub, Data.gov, etc.)

◦ Share data to generate new data

◦ Linked Open Vocabularies◦ Vocabularies repositories

◦ Facilitates data integration

◦ Linked Open Rules◦ Rules repositories

◦ Concept only

◦ Linked Open Services◦ Service repositories

◦ Concept only

Page 53: Semantic web: An overview

Thanks for your attention