This is a simple demo which shows what is an ontology; and how an ontology can be built for a temperature sensor.

1. Data Representation
Using
Ontologies
1

2. Contents
• Introduction
• Data specific issues in IoT
• Approaches used
• Ontology
• Demo
2

3. 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
3

4. Issues?
• Sensors are resource constrained devices
– Battery, processor and storage
• Date generation is continuous
– Leads to BIG DATA PROBLEM
• Generated data meaningful to limited users
only
– Only sensor itself and its deployer knows
• Human understandable and Machine
understandable data
– Celsius vs. kelvin
4

5. 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 users
only
– Only sensor itself and its deployer knows
• Human understandable and Machine
understandable data
5

6. 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
6

7. 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
7

8. 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.
8

9. Ontology
9

10. Basic Blocks of Ontology
• Classes
• Instances
• Relations
– A knows B
• TRIPLES
10

11. Example: A simple ontology of CS Department in US
11

12. Why we use Ontologies
• To share common understanding of the
structure of information among people or
machines
• To enable reuse of domain knowledge
• Ontologies allow us to infer extra knowledge
from basic facts encoded
12

13. Represent this in Ontology
13

14. Possible Ontology
Classes
Individuals
Subclasses
Relationship
14

15. Relationship
15

16. Expanded view of some individuals of Place(class) Mumbai
16

17. Internal details associated with each individual
17

18. Tools used and Demo
• Tools used: Protégé, Jena Framework
• Demo:
– Create an individual of ontology
– Display created individual in Protégé
– Perform queries on Ontology
18

19. References
• From sensor data to triples: Information flow
in semantic sensor networks
• Slides from www.slideshare.net
19

20. 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
20