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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>MyWorkPlace: Personalised information about a Ubiquitous Computing enabled building</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>David Carmichael</string-name>
          <email>dcarmich@it.usyd.edu.au</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Judy Kay</string-name>
          <email>judy@it.usyd.edu.au</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Bob Kummerfeld</string-name>
          <email>bob@it.usyd.edu.au</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>William Niu</string-name>
          <email>niu@it.usyd.edu.au</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>University of Sydney School of Information Technology NSW 2006</institution>
          <country country="AU">Australia</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>This paper describes MyWorkPlace, which uses personalisation of automatically generated ontologies to provide users with personalised information about new and invisible items within a ubiquitous computing environment. A key component of this system is the automatic generation of the ontologies, and models used to drive it. This data is being gathered from a number of sources including: building maps, the build manual, sta directory, student timetables, the departmental calendar and room bookings. We describe planned evaluation of the system in a deployment to a new building and its new inhabitants.</p>
      </abstract>
      <kwd-group>
        <kwd>User modelling</kwd>
        <kwd>Invisibility Problem</kwd>
        <kwd>Automatically Generated Ontologies</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>INTRODUCTION</title>
      <p>
        Ubiquitous computing aims to embed our everyday
environment with devices, sensors and services in such a way
that they are as unobtrusive as possible, to the point of
becoming invisible to common awareness [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. When achieved
this invisibility creates its own problems. Users may be
unable to discover what services are available to them, what
sensors are detecting them or why the system has reacted
in a particular way. We call this the Invisibility Problem [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]
      </p>
      <p>To motivate this paper we consider a real life example of
the invisibility problem, a University Department moving
to a new building instrumented with a number of
ubiquitous computing features. We examine the interactions and
information needs of Fred, an academic.</p>
      <p>Initially all facilities (ubiquitous computing and
otherwise) within the building are unknown to Fred. He may
have an idea of some types of facilities which are available,
but is unlikely to know the full extent of the facilities
available and details about them. A list of all the information
about the building, its sensors, services, devices and
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ubi-PCMM at UbiComp’06, September 2006, Orange County, CA, USA.
.
pants would have hundreds or thousands of items and clearly
overwhelm the user.</p>
      <p>MyWorkPlace solves this problem by modelling users, places,
devices, sensors, services and objects to provide personalised
views of the items within a user’s environment. An
important part of the system is the use of an automatically
generated ontology to assist with the selection of items to display
for the user.</p>
      <p>
        The ability for ontologies to facilitate human-machine and
machines-machine communications has gained wide
recognition in the development of the UbiComp. It has been used
in middleware to facilitate context management and
reasoning [
        <xref ref-type="bibr" rid="ref3 ref4 ref5">3, 4, 5</xref>
        ], and user modelling [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ].
      </p>
      <p>A novel aspect of our work is the use of ontological data
generated using dierent sources which have dierent levels
of reliability to personalise the information given to a user
based on their context.</p>
      <p>The eort in creating a comprehensive ontology is
substantial. Partial or completely automated generation has
the possibility to greatly reduce this eort. Depending on
the degree and type of automation, the reliability of the
ontology can vary greatly. To cope with this, we are examining
multiple levels of ontologies.</p>
      <p>Our automatically generated ontology in being built from
a number of sources including: building maps, the build
manual, sta directory, student timetables, the
departmental calendars and room bookings.</p>
      <p>The rest of this paper is organised as follows: We rst
describe some related work in Section 2 to set the scene.
Section 3 describes MyWorkPlace when used in the scenario
described of Fred. The methods we use for automatically
generating the ontologies are described in section 4. We
conclude with a discussion of our proposed evaluation and
future work in section 5.
2.</p>
    </sec>
    <sec id="sec-2">
      <title>RELATED WORK</title>
      <p>
        Weiser predicted that ubiquitous computing would
become a technology which disappeared and became
invisible [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Others such as Heer and Khooshabeh have
examined the nature of this invisibility [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ]. They note that an
invisible interface does not imply literal physical invisibility.
Edwards notes some of the problems associated with
Invisibility while examining the challenges of putting ubiquitous
computing into the home [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
      </p>
      <p>
        There has been some work which addresses the issue of
informing users of ubiquitous computing systems what devices
and services are available to them. The AFAIK system is
a multimodal help system for an intelligent room [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. Help
content must be entered in XML, but the help system is
not personalised to the user or their context. The
Digiscope [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] is a system for viewing attributes of objects within
an intelligent environment. It consists a large
semitransparent display mounted on an movable arm. Information is
retrieved from a database about objects which are identied
using RFID and visual tagging. The NearMe system [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]
provides users with a list of nearby devices by examining
the signatures of nearby wi access points, and making a
request to a server of all known nearby devices. This is
different from our work as it does not seek to deliver the same
level of detail and is not personalised.
      </p>
      <p>
        The CONON system [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ] is an OWL encoded context
ontology (CONON) for modelling context in pervasive
computing environments. Its context model is split into into an
upper ontology and other more specic ontologies. The
upper ontology describes high-level features of basic contextual
entities, of which, the most fundamental ones are location,
person, activity and computational entity. Then each
subdomain has a more specic ontology with additional details.
It is implemented using Jena2 Semantic Web Toolkit and
OWL-Lite. Reasoning is either: ontology reasoning using
description logic or user-dened reasoning using rst-order
logic. COBRA-ONT [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] is an ontology used in the Context
Broker Architecture (CoBrA) to facilitate knowledge
sharing and context reasoning in ubiquitous computing. The
system tries to determine location and status of agents
(human or software) with in it. COBRA-ONT is expressed in
OWL and models places, agents, and events. The ontology is
categorised into 4 themes: 1) physical places, 2) agents
(humans and software agents), 3) location text of the agents,
and 4) activity context of the agents.
      </p>
      <p>
        Outside of Ubiquitous Computing there has been work on
extracting ontologies from existing text sources. To do this
both concepts and relationships between them need to be
learned. ConceptNet [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ] is a massive ontology of
commonsense knowledge. The concepts and relationships are
extracted by processing the 70000 sentences of the Open Mind
Common Sense Project. The sentences are elicited from the
user in a semi-structured way in order to make the
information easier to extract. Khan and Luo [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] focus on concept
learning from a text corpus. Concepts are placed in a
hierarchy. However, the type of relation between them is
ignored; that is, it is only possible to tell two concepts are
related, but not how they are related. Some projects, such
as MindNet [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ], Mecureo [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ] and Janninik and
Wiederhold’s approach [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ], focus on extracting relations between
terms from dictionaries.
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. SYSTEM DESCRIPTION</title>
      <p>
        The MyWorkPlace system provides users with
personalised views of places, sensors, devices, services, objects and
people in their environment. This advances on our earlier
work, MyPlace, described in [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. The key dierence from
earlier work is the inclusion of an automatically generated
ontology to assist with the selection of items to show the
user.
      </p>
      <p>We now return to the scenario from the Introduction for
interactions of Fred, a member of sta interacting with
MyWorkPlace shortly after moving into the newly constructed
School of IT smart building.</p>
      <p>Fred is an academic who does not know very much about
the building. He knows the location of his own oce, and
those of the students he supervises. He knows approximately
where the the front counter is, but has not been there so is
unaware of what facilities are available. He knows nothing of
the seminar room, sta common room, pervasive computing
laboratory, or undergraduate computer laboratories.</p>
      <p>Figure 1 shows a screenshot from MyWorkPlace
personalised for Fred, as it would be shown on a PDA while he is
standing in the Foyer of the building.</p>
      <p>The Status bar at the top tells Fred what the system
believes his location and status is. In this case, his location
is believed to be the Foyer, because the Mac address of his
Bluetooth mobile phone has been detected there. There is
a details button to allow him to scrutinise and correct the
reasoning used for his location and status.</p>
      <p>The content panel of the main screen consists of ve
expandable headings. The headings are Devices at this
location, Nearby Devices, Nearby Places, Services /Events, and
People. Clicking a heading shows or hides the contents. The
[Show all items] button displays all the items the user is
allowed to use. It also allows the user to see why an item
was included or excluded by MyWorkPlace.</p>
      <p>The system must determine which of the myriad of
devices, sensors, places, services, events to display to Fred.
For each heading, it examines the evidence and places each
item into one of a number of relevance categories :
• Already knows - The user is believed to already know
about this, based on either user feedback, or
observations such as the use of a device, or being detected in
a location.
• Needs to learn - The information is thought to be
useful to the user and the user is believed not to already
know it. Whether information is useful to a user is
determined based on manually entered stereotypes, or
the generated ontologies.
• Needs to know now - This is a special case of Needs
to learn where the item is believed to be important
based some aspect of the users’ current context. For
example: If the user has stated they are on their way
to a seminar in a room they are believed not to know
the location of, then location of the the seminar room
is very important.
• Not relevant (Neutral) - The information is about
something for which there is no information suggesting that
it is useful to the user.
• Doesn’t want to know - The user has indicated that
they do not wish to be informed about this, or a very
similar item.</p>
      <p>The main screen shows items in the Needs to learn and
Needs to learn now categories. The user can override this
personalised selection of information to see all items and
their relevance categories by choosing the [Show all items]
button.</p>
      <p>The Nearby Places category in Figure 2 lists a number
of the places which Fred does not know about. There are
many others which he is not informed about as the system
does not believe they are relevant to him. For example with
suitable information in the system in the system it might be
able to omit details of the Undergraduate Laboratories, as
it is semester break so he is not currently teaching classes.</p>
      <p>Figure 2 shows the view when Fred returns to his oce.
Here are more devices he may wish to learn about. Clicking
on an items brings up more information about the object.
It includes usage instructions and troubleshooting
information. In addition to this, it includes links to related items,
as suggested from the automatically generated ontologies.
Each time Fred clicks a link requesting more information, a
piece of evidence is added to his user model suggesting he
knows about it.</p>
      <p>It is important for the user to be able nd out why a
certain item has been displayed to them, and others have not.
We call this scrutability. When a user clicks the [Show all
items] button the full list of items is colour coded
according to which of the ve relevance categories dened above it
belongs. An explanation of the reasoning used to categorise
each item is shown if the user hovers the mouse over it. An
example explanation might be You are teaching Algorithms
101, this room is used for Algorithms 101, and you have not
yet been detected there.
4.</p>
    </sec>
    <sec id="sec-4">
      <title>ONTOLOGY GENERATION</title>
      <p>
        The data in our ontology is being built from a number
of sources, such as building plans, sta directory, the
building manual, student timetables, the departmental calendar,
room bookings, and a relatively small, handcrafted base
ontology. The degree of automation used and level of user
input required in generating ontological information from
these sources varies considerably. The reliability of each
source also varies for a number of reasons, such as input
errors and frequency of maintenance. MyWorkPlace takes
account for the inaccuracy problem with its evidence
accretion and delayed resolution approach [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. This means that it
can apply simple, explainable reasoning processes for
dealing with conicting and noisy information.
      </p>
      <p>Our initial source for location relationships were the
building plans for each oor of the building. Features on the plans
are grouped in the relevant layers. For example all the room
number labels are in one layer, the room description texts
are in another, another layer holds all the doors, one layer
holds all the solid walls while another holds all the glass.
There are over 100 dierent layers in total.</p>
      <p>Analysis of the lines and text data in each layer allows us
to use relatively simple reasoning to determine rooms and
relationships between them (e.g. distance). Figure 3 shows
a section of the plans (left-hand side sub-gure), and further
extracts showing: a) only wall and door layers (top
righthand sub-gure), and b) only room number and label layers
(bottom right-hand sub-gure). The majority of the data
generated from these plans is assumed to be very reliable as
the building was built according to them.</p>
      <p>The departmental sta directory is also an important source
for automatic population of an ontology and user models.
The sta directory yields a list of all academics,
administrative sta and postgraduate students. It also gives
relationships between people and their research groups (e.g.
undergraduate coordinator, chair of a research group), oce
or workspace locations, and contact information. A
number of the student-supervisor links are also available in this
database. This data can be extracted with minimal human
interaction. However, it suers from some inaccuracies as
the phone list is not always kept completely up to date,
for example, when people move oces or change research
groups.</p>
      <p>
        Another source of ontological data is the building
manual. This documents various elements about the building
in a glossary and human readable format. Example entries
in the manual are an entry for fax that describes policies
for using a fax machine, and an entry for reception that
gives the opening hours and the location of the reception
desk. We believe we will be able to use Sago, a
descendant of Mecureo [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ], to extract implicit relationships from
this manual to populate the base ontology. Mecureo is an
ontology learning tool that takes a glossary and mines
relationships between the concepts, or glossary terms.
      </p>
      <p>We propose to use other sources, such as: the university
timetable that lists times and venues for every class in the
university; the departmental calendar and room bookings
that give scheduled times and locations for certain
activities. Both sources may help generate more evidence that
assists the MyWorkPlace system to deduce, say, current
location and activity for a person, and suitable activities for
certain venues. In future we may link databases of
particular class enrollments to generate views of MyWorkPlace for
undergraduate students. However, this information might
not be as reliable as some of the other sources.</p>
      <p>The nal source is a small, handcrafted base ontology.
This serves as a base for other sources to build on.
5.</p>
    </sec>
    <sec id="sec-5">
      <title>DISCUSSION</title>
      <p>At the time of writing the new building for which the
system has been implemented has only just been occupied.
We plan to evaluate this system by two methods: rstly
we will ask a number of users to perform a task requiring
knowledge of the building, and compare the performance
of a group of people given access to MyWorkPlace against
those who are only given access to the data sources used
to populate the ontology (probably building plans, building
manual, and phone list).</p>
      <p>The other form of evaluation we wish to perform is to
make MyWorkPlace available to volunteer academic sta
and postgraduate students, and record their use of the
system. In addition to this we will request feedback from a
sample of users.</p>
      <p>One aspect we are particularly interested in is how any
inaccuracies in the generated ontological data aect the user
experience. As mentioned previously some aspects of this
data are known to be very accurate, while others are
expected to contain some out of date or incorrect items.</p>
      <p>Another piece of future work is to investigate the use of
a suggested template and categories for entries in the
building manual to better facilitate information extraction. We
would also like to include data extracted from existing,
maturer ontologies.</p>
    </sec>
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