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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Requirements Engineering for Pervasive Healthcare Monitoring System</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Juliana Kamaroddin</string-name>
          <email>j.kamaroddin@lancaster.ac.uk</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>InfoLab21, Lancaster University</institution>
          ,
          <addr-line>Lancaster, LA1 4WA</addr-line>
          <country country="UK">United Kingdom</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>A pervasive healthcare monitoring system (PHCMS) is an intrusive technology designed to provide supports to assist people with health problems. PHCMS could eventually lead to a fully monitored and supervised life within a home and thus reduce dependency of people towards healthcare institutions. Following implementation of such monitoring devices, elements of privacy, emotions and personal values of users, caregivers and family members appear to be at risk. Although requirements elicitation is a relatively mature area of requirements engineering, techniques to elicit emotions and personal values in the context of pervasive healthcare are not formally discussed. This research will use a case study of a pervasive healthcare system. Various elicitation techniques will be applied to harness emotions and personal values that affect users of a PHCMS. The final aim of this research is to recommend a toolkit that consists of requirements elicitation techniques for requirements engineers that are suitable to harness non-functional requirements for such a PHCMS.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        Pervasive healthcare (also known as ambient healthcare or ubiquitous healthcare)
provides various types of health services, designed to support users individually
(according to user profiles), adaptively (according to the course of disease) and
sensitively (according to living conditions) [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. An example of pervasive healthcare
monitoring system (PHCMS) feature is to assist people with health problems to live
independently, such as reminding medicine intake and monitoring their movement to
enhance theirs safety. Advancement of pervasive healthcare technologies has reduced
people’s dependency towards healthcare institutions.
      </p>
      <p>This research is based on a case study called MODEM (Monitoring of Dementia
using Eye Movements). MODEM is one kind of PHCMS that uses eye tracking to
detect early sign of dementia through eyes movement with everyday activities such as
watching TV and making tea. Its vision is to capture eyes’ movement and people’s
behavior at a natural and relaxed mode in a home environment setting with ambient
and unnoticeable technologies.</p>
      <p>A PHCMS such as MODEM can be an intrusive technology in three forms:
physical obtrusion (physical presence of the device related to its function, location
and visual appearance), privacy invasion (undesirable disclosure of private or
personal information) and security risk (intruding the home via the system, and doing
harm or misusing the information with bad intensions). Fear of intrusion is one of
potential barriers that might prevent users, caregivers and family members from
adopting a PHCMS in their home. The development of such a PHCMS requires a
requirements engineering model that is adequate to capture and satisfy unnoticeable
non-functional requirements of users and other people that are affected by the system.</p>
      <p>
        This research proposes to apply the Personal Contextual Knowledge framework
[
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] in the context of PHCMS. This framework, as shown in Table 1 consists of two
layers: user characteristics and personal goals, which both are placed in the
perspectives of location and time. The aim of the framework is to describe individual
users’ needs, goals, and attributes, which may be important for systems that adapt at
runtime to user context.
The user characteristics layer of the framework represents the physical and mental
attributes of a single person, while the personal goals layer represents mental states
held by a person. A person’s physical and mental attributes will change over time, but
the user characteristics are relatively stable. In contrast, personal goals/values may
vary from motivations and values, which are stable over a person’s lifetime, to
shortterm goals. The perspectives of space and time that form crosscutting ‘aspects’ at
each layer are aimed to encourage analysis of the evolution and change in contextual
models.
      </p>
      <p>Techniques to elicit emotions and personal values in the context of pervasive
healthcare are not formally discussed in books. This has become a motivation for the
researcher to understand the role of emotions and personal values of users within
requirements engineering for pervasive healthcare context, with the final aim to
recommend requirements engineers with a toolkit of suitable requirement elicitation
techniques.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Related Work</title>
      <p>
        There are various elicitation techniques to help the requirements engineers extract
requirements from different stakeholders and they are not limited to one specific
technique and can use different techniques according to the situation and the available
time and resources [
        <xref ref-type="bibr" rid="ref3 ref4">3, 4</xref>
        ]. Most of the techniques have been adopted and adapted from
social science disciplines, and only a few have been specifically developed for
software requirements elicitation [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ]. This project would consider applying
interviews, focus groups, requirements workshops, scenarios, persona and
ethnographies techniques.
      </p>
      <p>
        Cysneiros [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ] reviewed a number of suggested requirements elicitation techniques
for healthcare systems. From his observation, each techniques has its own reason to
be chosen, but yet some modifications has to be done according to the situation so
these tehniques can be used efficiently. Sutcliffe and Sawyer [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] conducted a survey
to review requirements elicitation from the perspective of a framework categorising
the relative ‘knowness’ of requirements specification and Common Ground discourse
theory. The survey results suggest that elicitation techniques appear to be relatively
mature, although new areas of creative requirements are emerging.
      </p>
      <p>
        Thew and Sutcliffe [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] introduced a taxonomy and analysis method in
requirements engineering that aims to improve the elicitation and analysis of soft
issues, which include users’ motivations, emotions and values. Ramos and colleagues
[
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] argued that if emotions are ignored during requirement elicitation process, this
would abdicate incomplete requirements specification and can prevent successful
deployment of computer-based systems. They propose a constructionist requirements
elicitation process, which aims to create knowledge about emotions, values and
beliefs in the requirements engineering process.
      </p>
      <p>
        Harbers and colleagues [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] studied on embedding stakeholder values in the
requirements engineering process through a Value Story workshop. The Value Story
workshop is the result of a series of workshops inspired on the Value Dams and Flow
method [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ], and has been experimented with different formats [
        <xref ref-type="bibr" rid="ref12 ref13">12, 13</xref>
        ] contains the
following phases: (i) identify direct and indirect stakeholders of an envisioned system,
(ii) identify the values of each stakeholder group, (iii) provide one or more concrete
situations for each value and (iv) identify a stakeholder need for each concrete
situation. They found that values are significantly better incorporated in user stories
obtained in the Value Story workshop than through user stories obtained in regular
requirements elicitation workshops.
3
      </p>
    </sec>
    <sec id="sec-3">
      <title>Research Aim</title>
      <p>To recommend a toolkit that consists of requirements elicitation techniques that are
suitable for requirements engineers to harness non-functional requirements, e.g. user’s
emotions and personal values for such a PHCMS.
3.1
i)</p>
      <sec id="sec-3-1">
        <title>Research Questions</title>
        <p>What is the role of user’s emotions and personal values in understanding
requirements of such a PHCMS? This question aims to know the significance of
understanding user’s emotion and personal values of a PHCMS.
ii) How do we elicit user’s emotions and personal values for such a PHCMS? This
question aims to identify the right techniques to elicit non-functional
requirements of a PHCMS, i.e. user’ emotions and personal values.
iii) Is traditional requirements engineering model adequate to deal with the process
of eliciting user’s emotions and personal values? This question aims to
investigate whether traditional requirements engineering model able to elicit
user’s emotions and personal values by following its existing exercise?
3.2</p>
      </sec>
      <sec id="sec-3-2">
        <title>Research Hypothesis</title>
        <p>User’s emotions and personal values are important for understanding requirements for
such a PHCMS. This hypothesis aims to determine whether user’s emotions and
personal values are important for understanding a PHCMS.
3.3</p>
      </sec>
      <sec id="sec-3-3">
        <title>Research Objective</title>
        <p>To understand the role of user’s emotions and personal values within a PHCMS
context.
4</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Methodology</title>
      <p>
        This research adopts Design Science Methodology for Information System [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]. In
this section, design cycle is explained, which consists of problem investigation,
treatment design and treatment validation.
4.1
      </p>
      <sec id="sec-4-1">
        <title>Problem Investigation</title>
      </sec>
      <sec id="sec-4-2">
        <title>Stakeholders</title>
        <p>The stakeholders for this study have been identified from three categories, which are:
people in at-risk categories (e.g. developing dementia), family members living in the
same house with the people at-risk categories and requirements engineers involve
during requirements elicitation process. MODEM’s feasibility study will recruit
potential participants from University of the Third Age group. Further investigation
will recruit real study participants from the community.</p>
      </sec>
      <sec id="sec-4-3">
        <title>Stakeholder Goals</title>
        <p>MODEM users and their family members who live together would want a PHCMS
that does not violate their privacy, emotions and personal values as each family has
different beliefs and culture. Requirements engineers’ goal is to investigate
appropriate elicitation techniques that have ability to discover user’s emotions and
personal values of non-functional requirements at the best probability.</p>
      </sec>
      <sec id="sec-4-4">
        <title>Conceptual Problem Framework</title>
        <p>Fig.1 illustrates conceptual problem framework, where MODEM as a PHCMS is to
be installed as a domestic surveillance system technology in a home environment for
ageing people in at-risk categories, e.g. developing dementia. Its characteristic as a
surveillance system will capture images and videos of the targeted user and also other
people that are living within the surrounding of this system. It is assumed that
emotions and personal values of those people are affected by MODEM presence.
Each house has its own culture that is subjective to the owner’s beliefs and the region
where they come from. The dashed box justifies the motivation for investigating
appropriate elicitation techniques in pervasive healthcare domain that are suitable for
harnessing user’s emotions and personal values.</p>
      </sec>
      <sec id="sec-4-5">
        <title>Requirements for Emotions</title>
        <p>
          This research will adopt the emotional intelligence framework proposed by [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ],
which was adapted from [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ]. The framework contains classes of skills, grouped into
four branches: perceiving emotions, using emotions to facilitate thinking,
understanding emotional information and managing emotion. One fundamental
example of the skill is ability to detect and decipher emotions in faces, pictures and
voices. For example, as in PHCMS context, the elicitation techniques to be proposed
are able to perceive user’s fear of diagnosis towards dementia by MODEM, which is a
non-human entity.
        </p>
      </sec>
      <sec id="sec-4-6">
        <title>Requirements for Personal Values</title>
        <p>
          This research will adopt a taxonomy of user values, which is proposed based on
Rescher’s theory [
          <xref ref-type="bibr" rid="ref17">17</xref>
          ], card sorting experiments and expert interviews [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ].
        </p>
      </sec>
      <sec id="sec-4-7">
        <title>Planned Treatment</title>
        <p>
          The researcher and MODEM’s software development team will conduct a series of
elicitation techniques such as interviews, focus groups, scenarios, personas and
ethnographies in various requirements engineering workshops to harness emotions
and personal values requirements in the context of PHCMS users. A text-mining tool
called WMatrix will be used to support post-elicitation work to filter transcripts from
the elicitation activity because it has been proven to be efficient and energy saving
[
          <xref ref-type="bibr" rid="ref18">18</xref>
          ].
        </p>
        <p>Results from the elicitation activity engagement with PHCMS users will be analysed.
The next stage is the development of requirements elicitation toolkit, which involves
selection of elicitation techniques and development of tool protoyping.
The task of developing MODEM is not within the scope of the researcher’s work.
Once MODEM has been developed, the system will be set up in a simulation
environment and also at a participant’s house. MODEM will track the participants’
eyes movements through daily activity such as watching television and making tea.
4.3</p>
      </sec>
      <sec id="sec-4-8">
        <title>Treatment Validation</title>
        <p>The researcher will interview the participants, their caregivers and family members to
get their requirements’ satisfaction feedbacks regarding MODEM implementation. A
qualitative analysis will be carried out to validate elicitation techniques used during
requirements elicitation activity. Hence it is envisaged that a requirement elicitation
toolkit to harness user’s emotions and personal values within PHCMS domain can be
proposed to requirements engineers.
5</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Conclusion</title>
      <p>It is anticipated that implementation of pervasive health care monitoring system
(PHCMS) affects users’ emotions and personal values because of its intrusiveness
characteristic. It is important for requirements engineers to understand the role of
emotions and personal values of users, so that these non-functional requirements can
be satisfyingly harnessed during requirements elicitation activity. The aim of this
research is to recommend a toolkit that consists of elicitation techniques for such a
PHCMS. This research will use MODEM as a case study of pervasive healthcare
system.</p>
      <p>Currently the researcher has completed her initial problem analysis and identification
of elicitation techniques to be used and is planning for stakeholders’ engagement.
Once it has been done, the actual engagement will involve the application of
elicitation techniques for MODEM’s requirement elicitation activity.</p>
      <p>Acknowledgments. The researcher would like to thank the Ministry of Higher
Education (Malaysia) and Universiti Teknologi MARA for funding her PhD studies.</p>
    </sec>
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