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    <article-meta>
      <title-group>
        <article-title>Smarter Software Engineering Methods for Smart Environments</article-title>
      </title-group>
      <contrib-group>
        <aff id="aff0">
          <label>0</label>
          <institution>University of Waikato</institution>
          ,
          <addr-line>Hamilton</addr-line>
          ,
          <country country="NZ">New Zealand</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Wearable technology and improved processing of streaming data have contributed to the advancement of the Internet of Things (IoT) and its applications such as smart living and working environments. The development of use-cases for such solutions continue to evolve and are supported by research into security, privacy and UX, which are all seen as central to developing appropriate and acceptable solutions. Development of IoT systems may also follow best-practice engineering principles (model-driven development and testing, formal methods etc.) to ensure they will meet all requirements and perform as expected in (often) uncontrolled environments. We argue, however, that there are two key concepts that are still overlooked. We de ne these as `Data Sovereignty Management' (DSM) and `Quality of Life' measurements (QoL). In this paper we present examples of how and why DSM and QoL should be considered central within the development of IoT systems, and propose that software engineering methods be extended to include these.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        The increase in the availability of cheap, lightweight sensors and wearable
technology, alongside the development of smarter processing methods using edge and
fog computing, has helped to move Internet of Things (IoT) solutions into the
mainstream [
        <xref ref-type="bibr" rid="ref18 ref5">5, 18</xref>
        ]. Although the idea of IoT-enabled \smart cities" (where
interconnected devices, people and infrastructure can be used to make everyday
living easier) has been around for many years, there is an increasing desire to
scale this down to specialised \smart living" environments [
        <xref ref-type="bibr" rid="ref19 ref4">19, 4</xref>
        ]. These are
typically envisaged to provide support to enable groups such as the elderly, or those
with specialist medical needs, to live in their own homes (rather than moving
into care homes or hospital settings). They aim to use IoT solutions to ensure
that the people the technology is focussed on are safe (for example are following
medication protocols or maintaining routine behaviours).
      </p>
      <p>
        The development of such solutions leads to research questions based around
key considerations such as privacy and security of data collection [
        <xref ref-type="bibr" rid="ref1 ref20 ref8">1, 8, 20</xref>
        ];
optimising cloud computing via techniques such as fog and edge computing [
        <xref ref-type="bibr" rid="ref2 ref6">6, 2</xref>
        ];
the usability of the technologies that will surround people in their every day
lives [
        <xref ref-type="bibr" rid="ref15 ref17">17, 15</xref>
        ]. These, and similar topics, are at the heart of much of the research
that is undertaken when IoT solutions are developed. These often devolve into
Copyright © 2019 for this paper by its authors. Use permitted under Creative
Com-mons License Attribution 4.0 International (CC BY 4.0).
specialist research areas such as: Cyber-Security; network architecture; arti cial
intelligence; HCI or UX, which are then used as the basis for supporting new
solutions of the use of IoT in various domains.
      </p>
      <p>
        There are, of course, other considerations which we need to take into account
when developing these `smart' environments. One of these is understanding the
e ect that living in a smart environment has on the people who inhabit them.
This is di erent from UX and usability considerations as it needs to take into
account the long-term e ects of reduced autonomy (due to being forced into a
routine that is deemed safe by the system) or constant monitoring in peoples'
everyday lives. While this may be studied as a part of traditional HCI
evaluation studies (e.g. [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]) there is not a well-de ned approach for doing this or
understanding how to capture and use such data in general. This leads to
fundamental questions of how can we e ectively reason about these e ects during
the design process and, subsequently, in evaluation studies?
      </p>
      <p>
        Alongside these direct e ects of living in a smart environment there is also
the consideration of data, and more speci cally data ownership. IoT solutions
based around the monitoring of individuals or groups of inhabitants generate
large amounts of data which is both heterogenous and, in many cases, constantly
streaming (big data) much of which can be considered personal data. Initiatives
such as the EU General Data protection Regulation (GDPR) [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] have
highlighted the need to ensure users have control over how their data is used, and
by whom. While these regulations mandate greater transparency, they do not
necessarily address all of the relevant issues pertaining to personal data. This is
particularly relevant now that data has become a form of `currency'. There is
currently no guidance on how to assist developers in tracking all of the necessary
data sovereignty requirements throughout all parts of a development process.
      </p>
      <p>In this paper we contend that both the engineering principles we use to design
and develop IoT systems and smart environments, as well as the evaluation and
testing techniques we use to ensure they are usable and error-free, must be able
to include these more detailed considerations of the e ect on a user's quality of
life (QoL) as well as data sovereignty management (DSM) principles. We de ne
QoL to include not just the everyday experience of using (or living within) the
technologies, but the longer term implications on users' way of life from the use
of technology in this way as well as the management and ownership of data
collected by such technologies. DSM a ects the complete life-cycle of data from
sensing, communication, pattern analysis to long-term storage and access.</p>
      <p>We will argue in Section 3 that both software engineering methods and
modeldriven development techniques are lacking consideration for user quality of life
as well as data sovereignty management.</p>
      <p>In order to demonstrate how these problems may manifest we provide two
real-world examples of IoT solutions which highlight the issues identi ed, and
then suggest an approach to begin to address this.</p>
    </sec>
    <sec id="sec-2">
      <title>Examples</title>
      <sec id="sec-2-1">
        <title>Monitoring Workers in Hazardous Environments</title>
        <p>
          Since 2014 the Hakituri project1 has been investigating solutions based around
the use of wearable technology for workers in hazardous environments. The initial
aims of the project were to identify appropriate data that could be gathered
from workers in-situ that could be analysed and used to identify fatigue. This
was done with the goal of helping with accident prevention in high-risk work
environments, such as forestry [
          <xref ref-type="bibr" rid="ref3">3</xref>
          ].
        </p>
        <p>In the initial stages of the project a wide variety of personal and contextual
data types were considered and/or experimented with, for example: worker
activity levels based on step counts, role, heart-rate, heart-rate variability (HRV);
worker well-being based on hydration, sleep patterns; contextual factors such as
ambient temperature; humidity; terrain type.</p>
        <p>It was clear early on that while the workers who participated in our studies
were keen to be involved in research that may have potentially life-saving
bene ts, they were also uncomfortable with the nature of some of the data being
collected and how it might be used. For example, if a wearable solution
identies a worker as being fatigued and his boss is noti ed what is the result? Is the
worker given time to rest before continuing with his work, or sent home for the
rest of the day and not paid? These started to create ethical questions around
the type of data collection we wanted to do which related to the intended use
of the data vs. its actual use (worker safety vs. management tool). It also led
us to reconsider the use of o -the-shelf wearable solutions due to lack of data
ownership associated with such tools.</p>
        <p>The issues around data collection in this project are further complicated by
the fact that a large proportion of the workers in the target industry are Maori.
This means that, as we collect large amounts of data (numerous workers on a
daily basis), we are creating a large personal dataset, and therefore our DSM
needs to include the principles of indigenous data sovereignty [11{13].</p>
        <p>From these we identify our rst problem statement:
How can we ensure that data collected in IoT solutions is always treated in
accordance with the system requirements and the end-user wishes?</p>
        <p>Our proposed solution to this is that data must be treated as a rst-class
citizen in all parts of the development process. This means that at the
requirements stage we must identify and describe all aspects relating to: what data is
collected, how will it be used in all parts of the system, how/where is it stored,
who owns the data, who has access to the data etc. Then as we begin to develop
our system, we must continue to include DSM in whatever engineering process
we follow. So if we are using a model-based development process the models
must include the DSM and enable us to reason about it (e.g., to ensure the
requirements are met) in the same way that we reason about functional behaviour
and user interaction. Testing and evaluation methods must also be extended</p>
        <sec id="sec-2-1-1">
          <title>1 https://isdb.cms.waikato.ac.nz/research-projects/hakituri/</title>
          <p>to similarly include the DSM and ensure that the developed solution correctly
manages the data in accordance with the requirements.</p>
          <p>Including the data as a component in our software models will help to ensure
that we can reason about it within our development process. However, we also
need to consider DSM as a component with our human centred approaches.
That is, not only do we need to nd ways of gathering requirements about the
data from the stakeholders, but also ensure that our usability testing includes
this aspect. For example, we must ensure that if the user requirements are that
they should be able to specify di erent parts of the data and who has access
to these (in our forestry context this may be the supervisors of work teams or
family members who can see some, but not all, of the data) then we should
provide usable methods for users to de ne this personalisation. DSM, therefore,
includes both determining how the data should be managed as well as all aspects
of controlling that management both within the system and by the users.
2.2</p>
        </sec>
      </sec>
      <sec id="sec-2-2">
        <title>Developing Smart Home Environments for Elderly Care</title>
        <p>
          An increasingly common use-case proposed for smart-home environments is a
supportive environment for the elderly which enables them to continue to live in
their own home safely, see [
          <xref ref-type="bibr" rid="ref16 ref21 ref22 ref7">7, 16, 21, 22</xref>
          ] for just a few examples of this. Such
systems may be designed to monitor behaviour of those living in the environment
to ensure that they are `safe' which may be based on behaviour patterns,
adherence to medication protocols, identifying potential danger through fall analysis
etc. Depending on the complexity of such systems there are a number of
technical challenges that are typically identi ed that need to be addressed which
may include things like how the sensors are used to collect data and then make
predictions (AI and machine learning challenges), privacy and security of the
networks and data (cyber-security), structure of the system and its data ow to
ensure accuracy and coverage criteria (architecture) ability of the end-users to
interact safely and successfully with the systems (usability).
        </p>
        <p>What is typically missing from explorations about how to satisfactorily
develop such systems is an understanding of the impact on the quality of life of
those who are living in the environment. In 2015 the Super ux lab created the
\Uninvited Guests" short video2 for the ThingTank project3 which explored the
tensions between embedded technology designed to assist an elderly man living
alone and his desire for autonomy in his daily life. This has become part of an
ongoing dialogue which seeks to understand the real implications and impacts of
these smart environments on those who inhabit them. However, this has not yet
translated into any systematic development and evaluation methods which allow
us to understand such quality of life metrics during the development lifecycle.</p>
        <p>While usability and UX can consider the user's interactions with the system,
and to some extent how it makes them feel during that interaction, it does not
capture the longer term implications of having technology incorporated into our</p>
        <sec id="sec-2-2-1">
          <title>2 http://super ux.in/index.php/work/uninvited-guests/ 3 http://thingtank.org/</title>
          <p>
            everyday lives. A small example of this can be seen in the way tness trackers
are use. A study by Endeavour Partners found that a third of U.S. consumers
who purchased a particular brand of tness tracker stopped using it entirely
within six months [
            <xref ref-type="bibr" rid="ref14">14</xref>
            ]. Initially there is a novelty which leads to enjoyment and
good UX, the positive feedback and motivational aspects can both be appealing
and seem supportive to users. However, over time use typically drops o (and is
abandoned) as the intrusiveness of reminders, or the feeling of failure that may
be engendered if daily targets are not met degrades the user experience with
increased use.
          </p>
          <p>
            This leads to our second problem statement:
How can we measure the impact of IoT solutions on the quality of life of end
users to ensure that the solutions we propose and build are not just usable but
also acceptable?
This goes beyond traditional UX measures and requires us to nd tangible ways
of both measuring, and including the measurements of, QoL into all stages of a
development process. This requires the development of an evaluation framework
that can be used to predict the outcome of envisaged scenarios, as well as measure
them during traditional user evaluation. We also need to be able to measure
the potential impact of subversion (alongside traditional problems such as loss
of connectivity, data corruption etc.) that may occur with data collection to
understand the trustworthiness of the data before using it (e.g., following the
approach described in [
            <xref ref-type="bibr" rid="ref23">23</xref>
            ]).
3
          </p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Conclusion</title>
      <p>The QoL and DSM we have described are not distinct, but rather interconnected.
If the users' quality of life is negatively a ected by living within a smart
environment they may act to subvert the system or avoid using it, which then has
an impact on the quality of data being collected and ultimately the utility of the
system. Similarly if it is not transparent to users how their rights and interests
in the collected data are being managed and protected this may directly a ect
how they feel about the system and impact their quality of life.</p>
      <p>If we consider state-of-the-art software engineering methods, and in particular
model-driven development techniques, two dimensions are currently missing. The
rst is a reliable method for measuring and evaluating quality of life impact
(QoL), the second is a way of recording data management processes as a rst
class citizen in the model-driven engineering process. While we recognise both
of these concepts as important, the problem of developing engineering practices
that address these concerns during development, testing and evaluation has not
yet been addressed.</p>
      <p>Furthermore, while IoT technology is often considered as if it were providing
solitary solutions, most smart living environments will be a combination of
technology solutions, thus further complicating issues of long term impact on QoL
and increased complexity of DSM.</p>
      <p>The answer to the discussed problems will be to ensure that both QoL
metrics and DSM are included as rst-class citizens in robust software engineering
processes. In this way they can be reasoned about along with all other parts of
the systems being developed.</p>
    </sec>
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