Semantic Web technologies, both those envisaged and those already realised, have the potential to benefit domains where issues such as volume, complexity and heterogeneity can overcome traditional techniques. Sensor networks are one such area where the application of semantics is indicated by scale, complexity, and the need to integrate over heterogeneous standards, sensors and systems for multiple purposes and multiple disciplines. The Semantic Sensor Networks W3C Incubator is an international initiative to develop standards for sharing information collected by sensors and sensor networks over the Web, including an ontology for different types of sensing devices and their observations, and new approaches for the semantic markup of sensor descriptions and services that support sensor data exchange and sensor network management. Kerry will describe the ongoing effort to increase the quality and reduce the cost of capturing environmental data, to address the growing demand for information about the environmental systems that support Australia’s agricultural, resource and process-based industries.

1. Image: Burdekin Sensor Network,
Pavan Sikka & Google
Semantics & Sensors: The web of real-time
meaning
Kerry Taylor, CSIRO ICT Centre
W3C Track, Web Directions South
Sydney, 9th October 2009

2. Abstract
• Semantic Web technologies, both those envisaged and those already
realised, have the potential to benefit domains where issues such as
volume, complexity and heterogeneity can overcome traditional
techniques. Sensor networks are one such area where the application
of semantics is indicated by scale, complexity, and the need to
integrate over heterogeneous standards, sensors and systems for
multiple purposes and multiple disciplines.
• The Semantic Sensor Networks W3C Incubator is an international
initiative to develop standards for sharing information collected by
sensors and sensor networks over the Web, including an ontology for
different types of sensing devices and their observations, and new
approaches for the semantic markup of sensor descriptions and
services that support sensor data exchange and sensor network
management.
• Kerry will describe the ongoing effort to increase the quality and
reduce the cost of capturing environmental data, to address the
growing demand for information about the environmental systems that
support Australia’s agricultural, resource and process-based
industries.
CSIRO. Web Directions South, Sydney, 9 October 2009

3. Where are they heading?
Semantic Web Sensor Networks
• The web of data where web content is • The internet of things
processed by machines, without human • Wireless Sensor Networks, RFID, stream
readers. gauges, orbiting satellites, weather
• The web as a huge, dynamic, evolving stations, GPS, traffic sensors, ocean
database of facts, rather than pages, that buoys, animal and fish tags, cameras,
can be interpreted and presented in many habitat monitors.
ways (mashups). • Today there are 4 billion mobile sensing
• Fundamental importance of ontologies to devices plus even more fixed sensors. The
describe the fact that represents the data. US National Research Council predicts that
• RDF(S) emphasises labelled links as the this may grow to trillions by 2020.
source of meaning: essentially a graph • Record observations of a wide variety of
model either stored locally triple store or modalities: but a big part is time-series’ of
distributed as linked open data. A label numeric measurements.
(URI) uniquely identifies a concept. • The Open Geospatial Consortium has
• OWL emphasises inference as the source some web-service standards for shared
of meaning: a label also refers to a data access (Sensor Web Enablement).
package of logical axioms with a proof
theory. • Goal is to open up access to real-time and
• Usually, the two notions of meaning fit. archival data, and to combine in
applications.
• Goal to combine information and services
for targeted purpose and new knowledge.
• THE WEB OF MEANING • THE WEB OF REAL TIME DATA
CSIRO. Web Directions South, Sydney, 9 October 2009

4. So what is a semantic sensor network?
• Reduce the difficulty and open up Sensor Network use by:
• Allowing high-level specification of the data collection process;
• Across separately deployed sensor networks;
• Across heterogeneous sensor types; and
• Across heterogeneous sensor network platforms;
• Using high-level descriptions of sensor network capability; and
• Interfacing to data integration systems using similar query and
capability descriptions.
• To create a Web of Real Time Meaning!
CSIRO. Web Directions South, Sydney, 9 October 2009

5. SSN-XG: Semantic Sensor Network Incubator Group
Commenced 1 March 2009.
Two main objectives:
(a) the development of ontologies for describing sensors, and
(b) the extension of the Sensor Model Language (SML), one of
the four SWE languages, to support semantic annotations.
CSIRO. Web Directions South, Sydney, 9 October 2009

6. W3C Incubator Activity
• An incubator (XG) is a lightweight process to develop an
interest group and to get started.
• Initiated by W3C members, can have non-member experts by
invitation.
• Meet by telephone weekly
• Meet in person once or twice
• Use W3C assets: web site, wiki, mailing lists, teleconference
tools,…
• Deliverable in one year.
• Transition to “Working Group” if serious.
CSIRO. Web Directions South, Sydney, 9 October 2009

7. Membership of SSN-XG
• 38 people from 17 organisations, including
• CSIRO
• Universities in
• US, Germany, Finland, Spain, Britain.
• Multinationals
• Boeing, Ericsson.
• Small companies
• in semantics, communications, software
• Other research institutes
• DERI (Ireland), Fraunhofer (Germany), ETRI (Korea), MBARI (US), SRI
International (US), MITRE (US), US Defense, CTIC (Spain).
CSIRO. Web Directions South, Sydney, 9 October 2009

8. The work of the W3C SSN-XG
• Deliverables
• The report will describe a framework (ontologies) for semantically
describing sensors and
• How mappings can be constructed both from these ontologies to
existing standards and from suitably annotated documents
complying with existing standards to the ontologies.
• The submission will cover specification of semantic annotation of
Sensor Model Language (SML-S).
• Applications
• Discovery
• Documentation
• Controlled vocabulary
• Tasking
• Composition
CSIRO. Web Directions South, Sydney, 9 October 2009

9. Where we are up to: Ontology
CSIRO. Web Directions South, Sydney, 9 October 2009

10. Where we are up to: Annotation
• Use Cases
• RDF-ization of SWE standards
• Integration of sensor data
• Creation of semantic sensor Web mashups
• Different types of annotation
• As "composition by inclusion of remote resources"
• As "model reference to a ontological description"
• Possible Annotation Techniques
• XLink
• xlink:href maps to rdf:resource (GML has rdf-like structure)
• However, there are multiple different interpretations of XLink within OGC community
• Need mechanism to differentiate 'semantic annotations' from other uses of XLink
• RDFa
• RDFa provides formal syntax and interpretation of annotations
• However, mainly adopted by the XHTML community (but discussed as annotation
technique for XML in general)
• Extraction of semantics from other attributes and xml elements values
• Some elements in SWE could be filled with URIs directly.
CSIRO. Web Directions South, Sydney, 9 October 2009

11. What CSIRO is doing with it
CSIRO. Web Directions South, Sydney, 9 October 2009

12. Using Semantics to Program a Weather Station
• Aim to represent the function as
well as the programming
language of a sensor system as
an OWL DL ontology.
• Queries and programming
instructions are also ontological
concepts, entered through a
semantic interface extended from
Protégé.
• Classified through a reasoner
and translated to the native
language.
• Patent pending.
• Photo by Dr Kerry Taylor, CSIRO
CSIRO. Web Directions South, Sydney, 9 October 2009

13. Tasmanian Networks
Irrigated pasture
• A dense network of wireless soil moisture sensors is
helping improve water use efficiency at Elliott
Research Farm in north-western Tasmania. The goal
is to develop an intelligent sensor web that adapts its
sensing and processing behaviour in response to
real-time changes in the current situation or predicted
conditions.
Photo by Mr David McClenaghan, CSIRO
Hydrology
• A hydrological sensor web test-bed in Tasmania’s South Esk River
Catchment. A research platform to investigate linking sensors,
measuring environmental parameters such as rainfall, temperature and
wind speed, with numerical models used to predict water flow in river
catchments.
• Comprising: 7 weather stations, 12 rainfall gauges, 11 water level
monitors, and hydrological models.
CSIRO. Web Directions South, Sydney, 9 October 2009

14. Phenonet – microclimate sensing for plant phenomics
• Phenomics: Start with a particular observable trait or phenotype and
work to discover the causal gene.
• with Australian Plant Phenomics Facility, to examine the influence of
microclimate on test plantings intended to compare the phenomics of
grain varieties
• Photos Carl Davies, CSIRO Plant Industry, VRU.
CSIRO. Web Directions South, Sydney, 9 October 2009

15. Phenonet – microclimate sensing for plant phenomics
• Sensor networks allow for an intensity and convenience of data
collection not otherwise feasible.
• Using CSIRO-developed Fleck nodes sourced from
Powercom/Datacall.
• Variety of sensors: weather (wind speed & direction,
temperature, humidity), photosynthetically active radiation, leaf
temperature, soil moisture profile, soil temperature.
• Variety of sampling frequency, from daily to 5 minutes.
• Target deployment size 40-200 nodes.
• Aim of semantics: to assist in programming the sensor network.
CSIRO. Web Directions South, Sydney, 9 October 2009

16. SSN workshop at International Semantic Web
Conference 2009
• Follows a similar event in 2006 – but
much livelier 3 years on!
• ict.csiro.au/conferences/ssn/ssn09
(google semantic sensor networks
2009)
• 11 peer-reviewed papers on:
• surveys related to SSN-XG
• ontology acquisition
• composition
• contextual modelling & learning
• URIs and mashup architectures
• time series representations
• smart products
CSIRO. Web Directions South, Sydney, 9 October 2009

17. Sensors anywhere and Semantics everywhere!
• Sensor and domain ontologies provide a common view of the
data from the sensor networks and from other sources through
data integration to the application.
• Semantic queries provide a highly hardware- and application-
independent means of describing the sensor network and data
integration task
• Ontologies and semantic queries in the network provide a
natural link into semantic data integration at a higher level in
the software stack.
• Reasoning over the ontologies allows the generation of the low-
level operations that bind the system together:
• Code generation in the sensor networks;
• Mapping data from sensor networks, other databases;
• Connecting to and controlling modelling and analysis as web
services.
CSIRO. Web Directions South, Sydney, 9 October 2009

18. Acknowledgement
• The members of the W3C SSN-XG – especially Amit Sheth &
Cory Henson
• The CSIRO project teams – especially Dr Peter Lamb and Dr
Michael Compton
CSIRO. Web Directions South, Sydney, 9 October 2009

19. CSIRO ICT Centre
Kerry Taylor
Research Scientist
Phone: 02 6216 7038
Email: Kerry.Taylor@csiro.au
Web: www.ict.csiro.au
SSN-XG: www.w3.org/2005/Incubator/ssn/
Thank you
Contact Us
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