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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>End-User Development for Lifelogging and eWellness</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Barbara Rita Barricelli</string-name>
          <email>barricelli@di.unimi.it</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Author Keywords End User Development, Internet of Things</institution>
          ,
          <addr-line>Design, Human Factors; ETL (extract, transform and load) operations</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Stefano Valtolina Università degli Studi di Milano Via Comelico</institution>
          ,
          <addr-line>39/41 20135 Milan</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Università degli Studi di Milano Via Comelico</institution>
          ,
          <addr-line>39/41 20135 Milan</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <fpage>42</fpage>
      <lpage>48</lpage>
      <abstract>
        <p>The growing popularity of Internet of Things' devices, sensors, and applications available on the market is pushing towards a revolution of lifelogging and its relationship with wellness. Thanks to the characteristics of pervasiveness and mobility of wearable IoT tools, we are witnessing the emergence of a new research and development domain: the eWellness. Together with this, new challenges arise, and ask for effective methods and techniques to improve the way extraction, merge, analysis, visualization, and data sharing are currently managed. In this paper, we present our research study on the eWellness domain and in particular the design and development of the SmartFit framework, aimed at supporting the collaborative visual design of IoT rules by means of End-User Development techniques.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>
        Nowadays we are witnesses of the proliferations of
different sensor devices able to produce several types
of data that can be profitable used for advising people
on how to improve their lifestyle, health, and wellness.
The survey reported in [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ] underlines that many tools
in the Internet of Things (IoT) field, mainly focus on
hardware devices (sensors and actuators) and on
artificial intelligence techniques that may help to add
sophisticated capabilities to the processing of
information provided by hardware devices. A current
challenge in this domain concerns the need to conceive
it as a socio-technical system, which encompasses not
only a variety of hardware and software components,
such as sensors, actuators, mobile apps and Web
applications, but also people that are bound together
by social ties and personal relations and that are
virtually linked each other. This leads to what is to be
considered the Internet of Things ecosystem. In this
context, the main interest is to provide the users with
tools able at properly helping them in making sense of
the data originated from different sources (i.e., devices,
sensors) and for enabling them to understand and
exploit huge amount of data and events that are
eventually collected in time. In our research, we mainly
study applications of IoT technologies designed for a
specific scenario: The eWellness domain in which
people can collect data gathered through several
devices for monitoring and keeping track of weight,
sport/fitness activity, calories intake, and sleep quality.
In this domain, what is currently missing is a solution
able to support domain users (experts in monitoring or
in supervising physical activity of individual or teams)
in selecting relevant data sources and compose them
through End-User Development (EUD) techniques [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ],
so that users are enabled to self-construct their
contents to respond to their situational needs. In this
scenario, end users find themselves at the center of a
complex scenario that they need to manage in efficient,
effective, and satisfactory way. EUD represents the
ideal approach for empowering end users and make
them becoming unwitting developers in their own
environment [
        <xref ref-type="bibr" rid="ref3 ref4 ref5">3,4,5</xref>
        ].
      </p>
      <p>A scalable and efficient solutions should be devised that
can be applied by domain experts in configuring the
network of sensors (both physical and social), and
services. ETL (extract, transform and load) solutions,
usually applied off-line, need to be revised and applied
on-line for feeding the system with fresh and timely
data. Finally, a user-friendly environment has to be
conceived for properly supporting the user in the
analysis processes (sensor discovery, feeding, and
knowledge inference).</p>
      <p>
        Specifically, in this paper we present and discuss our
sociotechnical study on the design and development of
IoT ecosystems to be used by non-professional sport
teams. The peculiar structure of non-professional sport
organizations is characterized by the existence of small
teams with athletes who live different kind of lives,
being professionals in different domains and meeting
only for some hours a week. Keeping track of their
habits, in terms of physical activity, nutrition, sleep and
so on, would help the coaches in understanding the
variety of the team members and finding successful
schemes of training. In order to enable domain experts
in generating, configuring and managing the network of
sensors and services we adopt a meta-design
approach. By means of this approach we seek to create
social-technical conditions for broad participation in
design activities at both design and use time of all the
involved stakeholders, rather than anticipating all
requirements at design time [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. Objective, techniques
and processes are observed to empower users to be
active designers, creating their own situated solutions
that can be translated in a configuration of sensors and
services.
      </p>
    </sec>
    <sec id="sec-2">
      <title>The SmartFit Case Study</title>
      <p>
        In this section, we present a use case we studied to
experiment the potentials of our solutions both at
meta-design and design level. In this context of use we
consider three different Communities of Practice (CoPs)
[
        <xref ref-type="bibr" rid="ref7">7</xref>
        ] that co-exist in a eWellness scenario: IoT
engineers, Coaches and Trainers, and Athletes. IoT
sensors/devices engineers are in charge of connecting,
maintaining, and setting up the devices and sensors to
be used by coaches, trainers, and athletes. Their
system named StremaLoader, allows the design of data
flows by aggregating data sources and applying
operators to them for merging, joining and
transforming the gathered data. More details about this
environment are referred in [
        <xref ref-type="bibr" rid="ref8 ref9">8,9</xref>
        ]. The StreamLoader
output is a flow of events that can be used by coaches
and trainers for defining rules to monitor particular
situations and to adopt suitable actions according to the
occurrence of given conditions. Exploiting a rule
language, the Rule Editor enables coaches and trainers
to act as end user developers by designing the ECA
statements to be used to supervise athletes’
performances and lifestyle and they also analyze the
gathered data in their interactive system. Finally,
athletes can be seen as the real end users, the ones
who passively use the data gathered by the IoT sensors
and devices to better their lifestyle and sport
performances. A tailored interactive system can be
used to have a view on their behavior and
performances at any time during the day.
      </p>
    </sec>
    <sec id="sec-3">
      <title>Meta-Design Phase: The StreamLoader</title>
      <p>At meta-design level, IoT Engineers need to configure
the network of sensors and services for managing the
data-flow to be served at the Design level interactive
system. The outcome of this environment is to detect a
set of events that coaches and trainers need to
manipulate at design level for monitoring the physical
activities or daily behavior of their athletes.</p>
      <p>
        StreamLoader provides IoT Engineers with a set of ETL
operators used for manipulating streams of data in real
time (or almost real time). In this way, data are loaded
from a set of sensors and services, providing a
convenient way for user to real-timely read the data
information and make tactical decisions. Commercial
systems such as Talend Studio1, StreamBase Studio2,
Waylay.io3 offer graphical interfaces for designing
workflows and dataflows as graphs of connected nodes
representing tasks and data-sources. While Talend
works on static data coming from fixed data-sources,
StreamBase and WayLay can receive and analyze
continuous data streams and are specifically designed
for IoT. These environments provide rich user interface
support for the full application lifecycle but they are
desktop-based systems and in some cases, specific
conditions can be only created by adopting strategies
based on programming languages paradigms (as for
StreamSQL in StreamBase Studio) or by personalizing
existing templates having well-defined trigger policy (as
in Waylay.io). Visual queries are other examples of
solutions can be used for assisting users to extract
information from databases in an intuitive, visual and
1 www.talend.com
2 www.streambase.com
3 www.waylay.io
natural approach, making information systems
comprehensive and efficient for a wide range of
applications. SmartVortex Visual Query System [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ] is
a typical application where the visual strategy of
querying takes the form of drawings or graph. Also in
this case the expected users have limited competence
for managing data-streams but they wish to easily
express basic queries with little efforts and no
competence in developing code. Starting from the
study of current solutions based on graphical visual
strategies for executing ETL operations, we designed a
meta-design environment for helping the IoT engineers
to manipulate events. In our approach, one of the most
important EUD activity takes place during the
metadesign of the flow of events that characterize a context
of use. For example, in a gym, IoT engineers need to
combine data coming from different sensors and
devices for properly defining the exercises. These EUD
activities are exploited for executing efficiently and
effectively Event ETL operators. So far, several
operations have been developed for processing and
combining the streams produced by the sensors [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. In
the fitness example, the events might concern the
user’s physical condition, which will be used for
suggesting what exercises are better to perform, or
which precautions to follow for improving the quality of
live (for example, by changing the diet plan). In our
context, the meta-design environment is a Web
environment where IoT engineers can drag and drop
different sensor data sources and visually apply on
them a set of operations. This application offers an
engine and graphical environment for data
transformation and mashup. As depicted in Figure 1
(A), this mash-up consists of a user interface that
contextually displays icons of data sources or
operations in order to link, aggregate, merge or
transform data coming from different sensors. It relies
on the idea of providing a visual workflow generator for
letting the domain experts to create combination of
data originated by sources. In Figure 1, the IoT
engineer has taken data coming from an application
used for annotating the calories intake and three
sensors: Two for counting steps, and one for
monitoring the sleep. The engineer has then used a
merge operator for merging data coming from the two
step-counters and a transform operator for
transforming the minutes of sleep in hours. Finally,
s/he has joint these data into a flow that has been then
collected into the data-warehouse. An advanced use of
such visual paradigm allows the users to have an online
generation of sample data coming from the data
sources dragged-and-dropped on the canvas, or as
result of the operations carried out on them (see Figure
1 (B)). Following this strategy, information is gathered
from the network of devices and specific operations can
be triggered on user requests.
      </p>
    </sec>
    <sec id="sec-4">
      <title>Design Phase: Rule Editor</title>
      <p>The meta-design environment described earlier in this
Section and used by IoT Engineers, constitutes the
base for providing coaches and trainers with the
possibility to manipulate the flow of events in order to
monitor the physical activities or daily behavior of their
athletes. The design environment for manipulating
these events aims at offering a graphical visual
strategy for exploiting the potentials of an IoT
environment in the deployment of rules. Systems like
JBoss Drools4, OpenRules, and IBM WebSphereJRules5
provide platforms for supporting users in creating
complex rules to trigger proper actions when specific
conditions occur. In these environments, the coding of
complex rules is generally performed by skilled
technicians through ad-hoc Rule Engines. Nevertheless,
in real contexts of use, the definition of rules is
performed by domain experts that are not experienced
technician and prefer to use natural language or
graphical notations. Other visual strategies typically
used in IoT field for modelling ECA
(Event-ConditionAction) rules can be described through the most
famous systems that apply them: IFTTT, Atooma and
Yahoo's Pipes. The first two examples allow users to
define sets of desired behaviors in response to specific
events. The visual strategy aims at creating automated
rules by using graphical notation for programming
statements such as: "IF this DO That" or "WHEN trigger
THEN action". A second type of applications stems from
the outstanding work done with Yahoo's Pipes. These
applications are based on the idea of providing a visual
pipeline generator for supporting end users in creating
aggregation, filtering, and porting of data originated by
4 http://www.drools.org/
5 http://www.ibm.com/software/websphere/
sources. The visual strategies adopted by following
IFTTT or Yahoo's Pipes compliant solutions are
promising techniques but, in our opinion, they present
some lacks. The former offers a very simple and easy
to learn solution based on the definition of ad hoc rules
that can notify the end users when something happens
– e.g. when their favorite sites are updated, when they
check-in in some places or their friends do, or warn
them when specific weather conditions are going to
take place. However, the language is not enough
expressive for the specification of more sophisticated
rules based on time and space conditions. On the other
hand, the latter offers a too complex solution for
supporting the end user in expressing their
preferences. Pretending that end users can deal with
APIs of several sensors/devices put at risk the success
of the visual approach. Moreover, events in each
stream of an IoT scenario, are time and space
dependent and so the related rules need to take into
account these type of conditions. Nevertheless, in the
described systems, time and space dimensions are
almost neglected. Once the flow of events for a given
analysis have been identified by IoT engineers, rules
should be defined for specifying the action to be
actuated when specific events occur. Our system,
named Rule Editor, extends the IF-THIS-THEN-THAT
approach and supports the definition of rules in a more
articulated way by keeping the complexity at an
acceptable level. The idea is to keep the simplicity of
the IF-THIS-THEN-THAT system pairing it with the use
of formula languages. Moreover, time and space
dimensions are exploited and adopted for expressing
more loose rules in the statements. From the point of
view of language expressiveness, we consider rules
that are more expressive than the IF-THIS-THEN-THAT
system from different perspectives. Complex conditions
are supported to correlate events both from the
temporal and spatial dimensions. The time dimension
allows end users to set rules that can be fired at some
specific time, delayed in case of certain conditions are
verified, and may be repeated until some event
happens. The space dimension gives users the chance
of linking rules to the place/area where the events
currently taking place, where they will possibly be in
the future or where they are moving into. Moreover,
rules are enabled depending on spatio-temporal
conditions that are clearly outlined in the rule
specification. This allows the identification of the
streams that are really relevant in a given time and
given location for monitoring given situations and
properly react to them. By exploiting a Rule Language,
the rules can be specified by means of the graphical
Rule Editor. As depicted in Figure 2 the graphical
interface is based on drop-down menus that are
populated by using the attributes that characterize the
JSON of the flow of events produced by the IoT
Engineers with the SmartLoader environment.</p>
      <sec id="sec-4-1">
        <title>An example of Composite Rule creation is given in</title>
        <p>Figure 2, where the user has defined four rules: (i) R1:
Hours of sleep less than 7 (ii) R2: Calories intake at
dinner greater than 1,500 (iii) R3: Number of steps less
than 8,000 (iv) R4: Activity duration less than 45
(minutes). The rules are built in this way: R1 AND R2
AND (R3 OR R4). The meaning of the Composite Rule
created in this example is: “if the hours of sleep of the
day before are less than 7 AND if the calories intake at
dinner (before the sleep) is greater than 1,500 AND (if
the number of steps is less than 8,000 at day OR the
duration of physical activity is not less of 45 minutes at
day THEN send the athlete a message that warns about
the behavior and performances. The rule editor aims at
allowing non-technical people to specify rules by using
simple drop-down menus. The conditions can be
composed by combining groups of statements
connected by using the operator AND or OR. Temporal
conditions are defined as depicted in Figure 3 and use
the automatically assigned names of the Rules as
elements to be composed (R1, R2, R3, ...). An example
of temporal condition is that R3 (number of steps less
than 8,000) has to take place before R2 (calories intake
at dinner greater than 1,500) with a range of +/- 5
minutes. In other words, the dinner must begin within
5 minutes after the user has finished to walk (for less
of 8000 steps). Another complex temporal condition
can be: R4 (activity duration less than 45 minutes)
begins before of the R2 (Calories intake at dinner
greater than 1,500) and ends after +/- 10 minutes. In
other words, the trainer wants to check if her/his
athletes eat too much and how, if they eat not seated
at a table but when they are on the move and quickly
(in less than 45 minutes). Once a rule is created, it is
stored in a repository for further re-use or for sharing it
among members of a community of trainers and
coaches. In this way, it easy for other users to
customize existing rules according to their needs.</p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>Conclusions and Future Works</title>
      <sec id="sec-5-1">
        <title>In this paper, we have presented an approach for</title>
        <p>supporting IoT engineers, coaches and trainers in
designing and analyzing data-flows coming from a set
of physical/social sensors and services. At the moment
we are working for setting up a user test evaluation for
our eWellness system thanks to collaboration with the
CSI (Centro Sportivo Italiano – Italian Sport Centre). In
this use case, a set of sport teams will be involved in
order to perform a set of tasks. What we want to study
from the user tests, is how far our approach is able to
offer new possibilities both at the design and use time
and to understand how the idea to combine the design
and end user environments appears to be successful
and effective solution both for domain and technical
experts.</p>
      </sec>
    </sec>
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