Data Representation Using

Ontologies

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Contents

• Introduction

• Data specific issues in IoT

• Approaches used

• Ontology

• Demo

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Introduction

• IoT makes our life comfortable– Desktop (static) to Ubiquitous (mobile) computing

• IoT devices are mostly sensors– Motion, Pressure, Temperature, Light sensors

– Cameras, Microphones, GPS enabled devices

• Nature of data– Streaming data: audio/video recording

– Event Based: Temperature reading, RFID tag read, light curtain interrupt

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Issues?

• Sensors are resource constrained devices– Battery, processor and storage

• Date generation is continuous– Leads to BIG DATA PROBLEM

• Generated data meaningful to limited usersonly– Only sensor itself and its deployer knows

• Human understandable and Machineunderstandable data– Celsius vs. kelvin

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Will consider only

• Sensors are resource constrained devices

– Battery, processor and storage

• Date generation is continuous

– Leads to BIG DATA PROBLEM

• Generated data meaningful to limited usersonly

– Only sensor itself and its deployer knows

• Human understandable and Machineunderstandable data

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Approaches used

• Meaningless data add annotations (Metadata)

• Unstructured data suitable for human consumption but not machine understandable use standardized syntax (XML, RDF)

• Interoperability of data Use ontologies

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Will use

• Meaningless data add annotations (Metadata)

• Unstructured data suitable for human consumption but not machine understandable use standardized syntax (XML, RDF)

• Interoperability of data Use ontologies

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Ontology

• A data model that represents knowledge as a set of concepts within a domain and the relationship between these concepts

• It is be used to support reasoning about concepts.

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Ontology

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Basic Blocks of Ontology

• Classes

• Instances

• Relations– A knows B

• TRIPLES

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Example: A simple ontology of CS Department in US

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Why we use Ontologies

• To share common understanding of thestructure of information among people ormachines

• To enable reuse of domain knowledge

• Ontologies allow us to infer extra knowledgefrom basic facts encoded

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Represent this in Ontology

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Possible Ontology

Classes

Individuals

Subclasses

Relationship

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Relationship

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Expanded view of some individuals of Place(class) Mumbai

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Internal details associated with each individual

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Tools used and Demo

• Tools used: Protégé, Jena Framework

• Demo:

– Create an individual of ontology

– Display created individual in Protégé

– Perform queries on Ontology

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References

• From sensor data to triples: Information flow in semantic sensor networks

• Slides from www.slideshare.net

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Annexure 1

• Each resource(thing) is represented on web

• Organizations can refer to each others business definitions

• Models can be modularized and reused

• Third parties can understand the information

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