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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Sensory Semantic User Interfaces (SenSUI) (position paper)</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>David Bell</string-name>
          <email>David.Bell@brunel.ac.uk</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Bahareh Rahmanzadeh Heravi</string-name>
          <email>Bahareh.Heravi@brunel.ac.uk</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mark Lycett</string-name>
          <email>Mark.Lycett@brunel.ac.uk</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Adaptive User Interface</institution>
          ,
          <addr-line>Context Awareness, Semantic Web</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Fluidity Research Group Brunel University West London</institution>
          ,
          <addr-line>Uxbridge, UB8 3PH</addr-line>
          ,
          <country country="UK">UK</country>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2009</year>
      </pub-date>
      <fpage>6</fpage>
      <lpage>19</lpage>
      <abstract>
        <p>Rapid evolution of the World Wide Web with its underlying sources of data, knowledge, services and applications continually attempts to support a variety of users, with different backgrounds, requirements and capabilities. In such an environment, it is highly unlikely that a single user interface will prevail and be able to fulfill the requirements of each user adequately. Adaptive user interfaces are able to adapt information and application functionalities to the user context. In contrast, pervasive computing and sensor networks open new opportunities for context aware platforms, one that is able to improve user interface adaptation reacting to environmental and user sensors. Semantic web technologies and ontologies are able to capture sensor data and provide contextual information about the user, their actions, required applications and environment. This paper investigates the viability of an approach where semantic web technologies are used to maximize the efficacy of interface adaptation through the use of available ontology.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>In a pervasive computing environment, computer systems and devices seamlessly
integrate into the life of everyday users. In such an open and dynamic environment
different systems and sensors networks need to interoperate and in order to do so,
knowledge sharing and common understanding of the meaning of the shared
knowledge is a prerequisite. With rapid evolution of the World Wide Web and the
growth of sources of data and knowledge, different services and applications are now
accessible for a wide variety of users, including children, adults, elderly and disabled.
These users from different backgrounds have different requirements and different
capabilities and use a range of devices (traditional PC, mobile and ambient screens).
In such an environment, it is highly unlikely that a single user interface will prevail
and be able to fulfill the requirements of each user adequately. In dynamic and
complex environments, users need a flexible user interface that is able to take into
account the context and react to business knowledge and sensory input. In other word
user interfaces should be able to adapt themselves based on the sensed contextual data
from user and its environment, such as location, temperature, light, movements,
thoughts, physical states of users, etc.</p>
      <p>
        Sensors can tightly interact with the real world and monitor physical phenomena
like temperature, light, sound, movement, location and etc. Sensor networks are
normally application specific with no sharing or reusability of sensor data amongst
applications [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ]. In order for applications and services to be able to take advantage of
existing sensors and sensor networks they have be able to understand sensed data,
integrate and consume such data in a beneficial way. In order to enable data
integration, the meaning of sensory data needs to be understandable by different
applications and services. Importantly, there is a need for sensor data to be enriched
with semantic information [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ]. Context awareness is an important aspect of
ubiquitous computing and often facilitates the provision of appropriate services to the
user. Context provide information about the present status of objects, places and
devices in the environment [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]. A context aware system is a system that can use
context and adapt its functionalities consequently in order to provide adequate
information and services to the user [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ], [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ]. Sensors are able to play a major role in
context awareness and system adaptation. They enable acquisition of more context
information about the real world and having more context parameters the system
would be able to infer more usable knowledge and information and adapt itself to
those inferred knowledge. In ubiquitous computing and sensor networks, context
aware applications can play a significant role in utilising received information and
their context to provide services that are appropriate to a particular situation. Context
awareness is closely correlated with any adaptive system. By sensing context
information, context enabled applications can present context relevant information to
users, or modify their behaviour according to changes in the environment.
      </p>
      <p>
        An adaptive user interface autonomously adapts the display and available actions
to support the current goals and abilities of the user by monitoring user states
(behavioural, psychological, physiological, etc.), system tasks, and the current
situated requirements [
        <xref ref-type="bibr" rid="ref27">27</xref>
        ]. There is an important distinction between adaptive and
adaptable interfaces. In an adaptive interface, the system modifies the interface
dynamically, while in contrast an adaptable system allows the user to change the
presentation of the information and the interface according to their own preferences
[
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], [
        <xref ref-type="bibr" rid="ref27">27</xref>
        ]. There are advantages and disadvantages associated with both adaptive and
adaptable user interfaces. Adaptive systems enhance user performance by reducing
the workload through automation as well as providing updated context aware
information, which might not be available in non-adaptive systems. A consequence of
this is that adaptive user interfaces may result in the user feeling a loss of system
control; in some cases reduce the visibility of the system; and may cause usability and
mistrust issues [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], [
        <xref ref-type="bibr" rid="ref27">27</xref>
        ]. Adaptable user interfaces typically involve lower levels of
confusion for the user and subsequently higher level of trust in the system [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ].
However, they do not provide any on-the-fly adaptation and automation benefits.
Depending on the planned functionality of the system and its intended use one or
other of the approaches or a combination may be appropriate. Brusilovsky [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ]
suggests that systems can be adapted to two main categories; user characteristics and
environment. Both of these categories could be sensed and transferred to systems
using sensors. Semantics can also play an important role in user interface adaptation.
Interestingly good deal of attention has been paid to utilising semantic web
technologies for adapting user interfaces [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ], [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ], [
        <xref ref-type="bibr" rid="ref24">24</xref>
        ], [
        <xref ref-type="bibr" rid="ref28">28</xref>
        ]. Many of these
publications focus on adaptive e-learning systems or adaptive web site navigation.
However, not enough attention has been paid to sensor-based user interface
adaptation, although it can provide valuable information for adapting to user
characteristics and environment in order to provide more relevant services to the
users. The SensUI project aims to feel this gap and provide a sensor based semantic
user interface adaptation approach.
      </p>
      <p>The paper proposes a novel adaptive user interface approach and is structured as
follows. Section 2 presents the complexity of pervasive environments and current
application of semantic web technologies in the field. Section 3 proposes a vision of
adaptive user interfaces that we call sensory semantic user interfaces (SenSUI) and
Section 4 describes some of the current use of ontology and sensors. The paper
concludes with a research agenda derived from a comparison between the vision and
current state of art.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Semantic Web of Things - Technologies and Sensors</title>
      <p>
        The pervasive environment is a complex mix of hardware and software. Working
outwards, in Figure 1, the UBIS pervasive architecture is made up of a number of
devices (sensors, actuators, user interfaces etc.) that are interconnected on one or
more networks. On a Web scale, the environment becomes a Web of Things [
        <xref ref-type="bibr" rid="ref30">30</xref>
        ].
These devices can interface together in order to undertake specific tasks, for example
peer to peer content distribution, or with remote access to applications and services. In
order for mobile devices to access remote services or applications they must first
utilise pervasive middleware. Original middleware definitions describing a
middleware service as general purpose services that sit between platforms and
applications [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] appear too general (in light of such a UBIS environment with
application components sitting on many devices and applications) and functionally
specific definitions are required.
In a more pragmatic vein the architecture in Figure 1 can be used to construct a high
level architecture: Indentifying the applications, services and devices that are within
scope of the design before mapping networks and middleware required to create
connections between chosen components. Traditionally, these connections would be
envisaged at design time. Connections between specific applications and devices
would be designed – choosing or developing appropriate middleware and network
systems. New architectural components are required if automated middleware
pipelines and associated user interface are constructed on-the-fly in reaction to
recognised events (e.g. simple actions such as a person passing an ambient screen) in
a new and novel way. Additional relationships and dependencies between events,
applications and devices are a pre-requisite for any intelligent initiation of action.
      </p>
      <p>Flowing throughout the architecture are events on the middleware layers. Two
event channels are described that enable: (1) Events to be consumed and generated by
the Services and Applications (e.g. informing that a specific data item has changed)
and (2) Events to be consumed and generated by the pervasive devices (e.g. User X is
at location Y and is interested in Data Z). It is this additional stage that allows the
designer to explore both the capabilities and functionality of the devices and
applications (inputs, outputs, requirement – when and where etc.). Consequently, the
modelling of linkages between the applications, services and devices are in response
to specific events. Shared spaces (S) are also included in the middleware layer as
repositories of localised information and logic – embedded within the environment.
The space can viewed as a data cache with integrated logic that is able to react to the
cache and external events. Event messages (typically XML documents) are read by
the middleware that then identifies appropriate connections (interested parties).
Understanding the connection requires that appropriate models are constructed.</p>
      <p>
        The Semantic Web is an evolving extension of the current web, in which
information is given well-defined meaning and is machine processable [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]: It provides
a common framework that allows data to be shared and reused across applications and
community boundaries [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. Semantic Web technologies provide a powerful means of
defining concepts and the relationships between Things in the real world. Ontologies
are a fundamental part of semantic web technologies – providing a formal description
of concepts and their relationships within a domain [
        <xref ref-type="bibr" rid="ref32">32</xref>
        ] and facilitate a shared
understanding of a domain. An ontology in computer and information science is “an
explicit specification of a conceptualisation” [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ]. Consequently, formal logic can be
used to infer new explicit knowledge from implicit knowledge that exists in the
domain definition. Similar to web documents, which are defined using standards,
ontologies also need a standard way of description. There are a number of languages
for describing ontologies. At present the most widely used ontology languages, also
W3C recommendations, are Resource Description Framework (RDF), Resource
Description Framework Schema (RDFS), and Web Ontology Language (OWL); and
all are based on XML.
      </p>
      <p>
        Information received from different sensors used as contextual information, with
examples such as light, speed, user thoughts, RFID input, etc. However, with
information coming from various sensors in varying data formats – semantic
differences result. Ontologies are an appropriate means for representing and capturing
context and sensor data, with associated knowledge acquisition and reasoning.
Semantic web technologies could enable semantic integration of received sensory
data and as a result context awareness and system adaptability based on the
harmonised context data. Ontologies are able to capture the definitions and
interrelationships of concepts in a variety of domains and enable presentation based
on reasoning and knowledge deduction. This also facilitates transparent flow of
semantically enriched information and knowledge and would enable sensor data and
contextual information integration as it flows through the overall system. There are a
considerable number of publications and projects that combine semantic web
technology and sensors [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ], [
        <xref ref-type="bibr" rid="ref22">22</xref>
        ], [
        <xref ref-type="bibr" rid="ref29">29</xref>
        ], [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ], [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ], [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ], [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ], [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ]. Section 4 will
review literature on this and existing ontologies. The complex architecture already
described warrants a more detailed exploration of a central part of the overall
architecture – the user interface. Therefore, a vision of how the user interface is able
to benefit from semantic web and sensor technologies is now presented.
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. Sensory Semantic User Interface vision</title>
      <p>A sensory semantic user interface (SenSUI) is adaptive to user activities through the
use of sensor and semantic web technologies. A SenSUI vision is an architecture that
is able to provide an adaptive user interface made available through explicit and
inferred knowledge – with the integration and utilization of existing and evolving
ontologies. Figure 2 depicts such architecture.
The high level SenSUI architecture is based around a software container (typically
placed in or associated with a physical location or person). There are various sensors
connected to the SensUI container (middleware is not considered at this point as it is
assumed in place from earlier UBIS architectural work) and it provides real-world
sensory data (e.g. contextual information). On the other side of the system there are
different users with different interest and capabilities who are interacting with the
system, using specialised user interfaces. For example, the user may interact with the
same application using a laptop, mobile phone or ambient screen as they move
between locations. Importantly, in order to (1) understand the sensors (2)
automatically adapt the rendered user interfaces and its links to existing application
systems, ontology must first be loaded into the container. These ontologies could be
device ontologies supporting device recognition and classification; environment
ontologies that provide information about the environment and context of the system
and user; ontologies that represent data formats and thus enable integration of the
different sets of data sensed by different sensors; and finally domain ontologies that
could enable understanding of the meaning of concepts in a particular domain.
Hence, the adaptive nature of the user interface is premised on the availability and
integration of suitable ontology. In order to explore that viability of such a vision,
current ontology use in this area is now reviewed.</p>
    </sec>
    <sec id="sec-4">
      <title>4. Ontology and Sensors</title>
      <p>
        Huang and Javed [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ] introduce data integration of sensor information as the most
challenging task due to the heterogeneous data sources present in Wireless Sensor
Networks (WSNs) for example. They propose a Semantic Web Architecture for
Sensor Networks which allows the sensor data to be understood and processed in a
meaningful way by a variety of applications with different purposes. They have
developed ontologies for sensor data and used the Jena API for querying and
inference over sensor data. Lionel et al. [
        <xref ref-type="bibr" rid="ref22">22</xref>
        ] have identified the same problems for
heterogeneous sensory data and have proposed a concept of Semantic Sensor Net
(SSN). A SSN is a heterogeneous sensor network enabling dynamic tagging of
semantic information to sensory data so that it can be integrated and reused across
various applications. Sheth et al. [
        <xref ref-type="bibr" rid="ref29">29</xref>
        ] also point out the problems associated with the
lack of integration and communication between sensor networks and refer to this
situation as having too much data and not enough knowledge. They propose Semantic
Sensor Web (SSW) framework, which provides enhanced meaning for sensor data by
annotating the sensory data with semantic metadata. This approach leverage
standardisation efforts of the OGC (Open Geospatial Consortium) [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] and Semantic
Web Activity of the W3C to provide enhanced description and meaning to sensor
data. Lewis et al. [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ] present a data management tool called ES3N which addresses
the issues of efficient sensor data storage and query processing using semantic web
techniques. Krco et al. [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ] point out that currently sensor solutions are used for a
particular purpose and deploying new service or changing service provider requires
considerable work - making re-use of sensors difficult.
Chen et al. [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] believe that a shared ontology is required in pervasive computing
systems for supporting knowledge sharing, context reasoning and interoperability.
They have developed SOUPA, a Standards Ontology for Ubiquitous and Pervasive
Applications to address this requirement. Bornhovd et al. [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] take a business oriented
look at the sensor data and point out that smart item technology can provide
companies with more accurate data about their business operations and also help them
to streamline and automate those operations. They believe this would result in cost
reduction as well as greater business effectiveness. They discuss how SAP’s Auto-ID
infrastructure enables the integration of RFID and sensor technologies with existing
business processes with the aforementioned view. [
        <xref ref-type="bibr" rid="ref31">31</xref>
        ] stress the importance of
Ubicomp technology in the future and its impact on business processes. They provide
a Ubicomp process model based on a collection of application cases and identify four
basic functions to be most affected - identification, monitoring, tracking and
notification. However, they do not provide any general framework that supports
process aware organisation. Liu and Zhao [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ] presented the idea of open sensor-rich
information system. Their motivation for using common ontologies is to capture the
sensor data in hierarchal form so that reasoning can be done on sensor data. Noguchi
et al. [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ] proposed automatic generation and connection of program components for
sensor data processing in network middleware. The raw sensor data is described in
RDF and they implement behaviour detection services to validate automatic
generation and connection.
      </p>
      <p>It can be seen that sensors can play a major role in context awareness and adaptive
system. Acquiring more context information from real world would improve the
effectiveness of adaptive user interfaces. However, none of the work to date provides
a solution using different ontologies in conjunction with sensory data to achieve
context awareness and adaptive user interfaces.
4.1. Current Ontology in the area
Considering the benefits that can be achieved by understanding and sharing sensory
data, current ontology are presented as a likely means to achieving this. Table 1
provides an overview of existing ontologies that are used in ubiquitous computing and
sensor related projects.
Ontology
COBRA-ONT
SOUPA
GLOSS
CoOL
CONON
GAS
CoDAMoS
CSIRO/SSN
Ontology
Ontonym
A3ME
SensorData
Ontology</p>
      <p>Description
Provides a set of ontologies for modeling context
in the smart meeting applications. It provides
ontologies for place, meeting, agent, place,
context, time, etc.</p>
      <p>Designed to model and support pervasive
computing applications. It has references to other
ontologies such as FOAF, OpenCyc Spatial
Ontologies, COBRA-ONT, Rei Policy Ontology,
etc.</p>
      <p>Describe a small set of concepts for a universe of
discourse for understanding global smart spaces.</p>
      <p>Gloss ontology and associated class model are
organised into four packages, namely
Universe, Interaction, Space, Time.</p>
      <p>Derived from ASC (Aspect-Scale-Context) to
facilitate ontology-based contextual
interoperability. The ASC model has been
designed to allow the representation of different
aspects of context, such as temperature, distance,
speed, etc.</p>
      <p>An ontology-based context model, in which a
hierarchical approach is adopted for designing
context ontologies. CONON’s main focus is on
location, user, activity and computational entity.</p>
      <p>Provides a common language for communication
and collaboration amongst the heterogeneous
devices that constitute a ubiquitous computing
environment.</p>
      <p>Provides an adaptable and extensible ontology
for creating context-aware computing
infrastructures, ranging from small embedded
devices to high-end service platforms.</p>
      <p>Designed for describing and reasoning about
sensors, observations and scientific models. It
provides classes for concepts such as sensors,
observation, location, identification, etc.</p>
      <p>A set of upper ontologies that represent core
concepts in pervasive computing such as time,
location, people, sensing, provenance, events,
device and resource.</p>
      <p>Provides a basic classification for self
description and discovery of devices and their
capabilities in heterogeneous networks including
resource constrained sensor nodes.</p>
      <p>Describes a sensor data ontology and is created
based on Sensor Web Enablement specifications.</p>
      <p>Proc. Semantic Sensor Networks 2009, page 103
Ontology
MMI Device
Ontology
CESN Ontology
NASA SWEET</p>
      <p>Description
An ontology of oceanographic devices, including
both sensors and samplers.</p>
      <p>An ontology for coastal environment domain.</p>
      <p>A set of ontologies for earth and environmental
domain.
The ontologies have been categorised as Devices, Context, Data and Domain
ontology.</p>
      <p>
        Devices Ontology focus on classifying and recognising different devices in the
environment. These devices can be different types of sensors and actuators such as
motion sensors, microphone, etc or different user interfaces such as mobile phones,
laptops, etc. Ontosensor is a prototype sensor knowledge repository compatible with
evolving Semantic Web infrastructure. It references and extends SUMO and is
partially based on SensorML [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]. This ontology defines different classes for different
sort of sensor types and sensor models. Sensors and devices included in this ontology
range from acoustic sensors, e.g. microphone to chemical and motion sensor. For
example GPS is a type of sensor, XBow_GPS is a type of GPS and MTS310_GPS is
a model of XBow_GPS. Figure 3 depicts a part of OntoSensor ontology related to
Microphone as a sensor. It can be seen in this ontology, and other device ontologies,
that it is not only devices and sensors that are included, but also in some cases
different models for a specific senor type. Typically, this is why ontology is
categorised under Devices. A3ME provides simple classification for self description
and discovery of devices and their capabilities in heterogeneous networks that
includes resource constrained sensor nodes. This ontology is categorised under
Devices as it provides an extensive taxonomy for devices and their capabilities. MMI
(Marine Metadata Interoperability) Device ontology is another example of a device
ontology covering oceanographic devices, including both sensors and samplers. This
ontology can easily be categorised under Devices category as its main priority is to
broadly characterise devices in the domain. In addition, it is produced specifically for
the Marine industry and therefore categorised under Domain ontology as well.
Context Ontology focus on environmental and contextual information, e.g. Location,
temperature, etc. This information can be transferred to application systems by
sensors. Three examples of Context ontology are reviewed. The CoDAMoS context
ontology [
        <xref ref-type="bibr" rid="ref25">25</xref>
        ] provides an adaptable and extensible ontology for creating
contextaware computing infrastructures, ranging from small embedded devices to high-end
service platforms. This ontology is classified under four basic concepts: User,
Environment, Platform, and Service [
        <xref ref-type="bibr" rid="ref26">26</xref>
        ]. CoDAMoS is categorised under Context
category as its focus is on context-aware infrastructure. CoOL, the Context Ontology
Language, is derived from ASC (Aspect-Scale-Context) to facilitate ontology-based
contextual interoperability. Ontologies implemented in ASC facilitate service
discovery and service interoperability at a context level. CoOL is used to enable
context interoperability and context-awareness during service discovery and
execution [
        <xref ref-type="bibr" rid="ref33">33</xref>
        ]. Ontonym is a set of upper ontologies that represent core concepts in
pervasive computing such as time, location, people, sensing, provenance, events,
device and resource. Thus, the ontology is categorised under Context. Ontonym is not
categorised under Device as its device coverage is limited.
      </p>
      <p>
        Data Ontology are concerned about the data received from different sensors and
integration of such sensory data. The data can range from Sensor name/type, location,
identifier, temperature, etc. The difference between Data and Devices ontologies is
that Data ontologies focus on received data and its meaning, while Devices ontologies
are mainly concerned about devices categorisation and having a complete ontology
that covers the expected devices and sensors in a device/sensor network. These two
types of ontologies might be used in conjunction. Context category may be considered
as a type of Data ontology with focus on contextual data received from the
environment. SensorData Ontology is an example of Data ontology. It is developed
based on Sensor Web Enablement (SWE) [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] specifications. SensorData Ontology
provides ontologies for SensorML, Sensor Observation and measurement
specifications defined in SWE. This ontology is categorised under Devices as well as
Data as it is mainly based on SWE’s SensorML and O&amp;M specifications, which are
concerned with sensors, their characteristics, capabilities and observed sensory data.
Another example for Data ontology is CSIRO Semantic Sensor Network (SSN)
ontology, which is used in the description and reasoning about sensors,
observations and scientific models. SSN also provides information about sensors and
their characteristics and functionalities. For example, it defines classes for
identification such as Manufacturer ID, Model Name, Model Number and Version.
However, this ontology does not provide any specific categorisation for a specific
sensor, but for a group of sensors. For example it defines classes for Nuclear,
Thermal, Acoustic and Chemical sensors, but does not define any specific sensor
model as in OntoSensor. SSN is also categorised as a context ontology as it provides
contextual information. Figure 4 depicts a part of Semantic Sensor Network ontology.
Domain ontology represent specific domains, e.g. the physical environment.
Examples of Domain ontologies are MMI Device, as explained above, CESN (Coastal
Environment Sensor Network ontology) and NASA SWEET (Semantic Web for
Earth and Environmental Terminology) ontologies. CESN focuses mainly on the
instruments in the domain including the sensors. Different types of sensors are
defined in this ontology such as Pressure Sensor, Thermometer, Hygrometer, etc.
Also specific sensors are defined in this ontology such as
HOBO_S-THBM002_RelHumiditySensor which is a Hygrometer or
HOBO_S-TMAM002_TemperatureSensor (a Thermometer Sensor). This ontology is categorised
under Domain as it provides domain specific information as well as Devices as it
clearly defines devices and sensors in the domain. Figure 5 depicts a part of CESN
ontology. NASA SWEET ontology is specific to earth and environmental domain. Its
focus is mainly on the environmental phenomena, such as weather, climate, flood, etc.
SWEET is categorised as both a Domain ontology and a Context ontology because
the phenomena that it captures can be considered contextual indicators.
It is important to note that these categories are not mutually exclusive and the purpose
of the categorisation is to identify the main purpose of each ontologies. Furthermore,
many of the ontologies exist in more than one category that is again because they can
have more than one purpose. It should also be noted that some of the ontologies
reference external ontology (e.g. Time Ontology), which can broaden their scope.
Interestingly, no ontology covers all categories and this could highlight the need to
bring together a number of ontology as each category is required for SenSUI.
      </p>
    </sec>
    <sec id="sec-5">
      <title>5. Research Agenda</title>
      <p>When considering current state of art ontology as a basis for realising the SenSUI
vision a number of research question require consideration:</p>
      <p>How should ontology be used to model user interface components and the data
contained within them (in relation to sensor related ontology)?
How are suitable ontology discovered and selected for use within the SenSUI
container?
How can ontology be integrated pre-, during and post- use (e.g. devices described
in a number of separate ontology)?
Which of the ontology identified provides the most utility for user interface
generation?
What are the relationships between the events that trigger user interface changes
and sensor data? Further, where are the relationships to the underlying
application systems?
What rules are required to process a sensor data alongside a combination of
device, context, data and domain ontology?
What are the demarcation lines separating different user interface renderings and
how is this defined (rules, ontology, applications)?
What is the temporal scope of sensor data in a user interface context (e.g. how
long does the RFID sensing of you next to the ambient screen apply)?
How domain neutral can a system become? For example, is it possible to drop a
domain ontology into a SenSUI architecture for it to work in the new domain?
How can ontology be rated (again with respect to duplicity) and how dynamic is
this in a SenSUI environment?
Undertake an in-dept study and testing of existing ontologies for “in-use”
applicability within a SenSUI platform.</p>
      <p>Identify further ontologies and categories of ontology – including their
relationships with those already discussed (e.g. Service Ontology).</p>
      <p>What are the additional middleware requirements in order to adapt user interfaces
based on sensory data and defined ontologies?
How can inter-related ontology be harmonised before or during use (e.g. several
device ontology together – or – different categories of ontology)?
Is it possible to add more context and domain ontologies in the future to
automatically enhance the capabilities of the middleware and user interface?</p>
    </sec>
    <sec id="sec-6">
      <title>6. Conclusion</title>
      <p>This paper proposes a novel approach to adaptive user interface engineering that
makes use of both sensor and semantic web technologies. Current state of art
Semantic Web approaches are reviewed in relation to an architectural vision of
Sensory Semantic User Interfaces (SenSUI). A SenSUI container model is presented
that consumes both sensor data and ontology in order to automatically generate
specialised user interfaces. Devices, Context, Data and Domain ontology have been
identified as possible candidates for the SenSUI platform. The outcome of the review
is a research agenda focused primarily on the selection and use of ontology to
improve the adaptability of user interfaces in a pervasive environment.</p>
    </sec>
  </body>
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