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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>An End-User Development Approach for Crafting Smart Interactive Experiences</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Antonio Piccinno</string-name>
          <email>antonio.piccinno@uniba.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>
          <xref ref-type="aff" rid="aff3">3</xref>
          <xref ref-type="aff" rid="aff4">4</xref>
          <xref ref-type="aff" rid="aff5">5</xref>
          <xref ref-type="aff" rid="aff6">6</xref>
          <xref ref-type="aff" rid="aff7">7</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Author Keywords Internet of Things; Smart Object Modelling; Smart Visit Experience; Cultural Heritage</institution>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Carmelo Ardito University of Bari Aldo Moro via Orabona</institution>
          ,
          <addr-line>4 70125 - Bari</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Giuseppe Desolda University of Bari Aldo Moro via Orabona</institution>
          ,
          <addr-line>4 70125 - Bari</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff3">
          <label>3</label>
          <institution>Maria Francesca Costabile University of Bari Aldo Moro via Orabona</institution>
          ,
          <addr-line>4 70125 - Bari</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff4">
          <label>4</label>
          <institution>Maristella Matera Politecnico di Milano Piazza Leonardo da Vinci</institution>
          ,
          <addr-line>32 20134 - Milano</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff5">
          <label>5</label>
          <institution>Paolo Buono University of Bari Aldo Moro via Orabona</institution>
          ,
          <addr-line>4 70125 - Bari</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff6">
          <label>6</label>
          <institution>Rosa Lanzilotti University of Bari Aldo Moro via Orabona</institution>
          ,
          <addr-line>4 70125 - Bari</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
        <aff id="aff7">
          <label>7</label>
          <institution>University of Bari Aldo Moro via Orabona</institution>
          ,
          <addr-line>4 70125 - Bari</addr-line>
          ,
          <country country="IT">Italy</country>
        </aff>
      </contrib-group>
      <fpage>23</fpage>
      <lpage>30</lpage>
      <abstract>
        <p>Despite the advantages that Internet of Things (IoT) technology offers, there are still important issues to be solved to increase its practical impact. The opportunities offered by IoT can be amplified if new approaches, based on high-level abstractions and adequate interaction paradigms, are conceived to involve directly non-technical users in configuring the behavior of their smart objects. In this paper, we present our End-User Development approach, which we would like to discuss at the workshop together with the challenges our future research implies.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>Copyright © 2018 for this paper held by its author(s). Copying
permitted for private and academic purposes.</p>
    </sec>
    <sec id="sec-2">
      <title>Introduction and Motivation</title>
      <p>Smart objects are increasingly pervading the
environments we live in. If enabled to exploit the
abundance of resources (object functionality, produced
data, related applications), end users could compose
the “behavior” of the surrounding environment to
accommodate their everyday needs. However,
programming the behavior of smart objects is currently
a prerogative reserved for professional developers, as it
requires the use of scripting languages and tools that
can also vary depending on the underlying hardware.
Furthermore, the available objects often expose very
specific functionalities that do not result in useful
services able to accommodate users’ needs.</p>
      <sec id="sec-2-1">
        <title>In order to directly involve non-technical users in</title>
        <p>
          configuring the behavior of their smart objects, new
approaches, based on high-level abstractions and
adequate interaction paradigms, have to be conceived.
Our research capitalizes on years of experience on
EndUser Development (EUD), a discipline that
encompasses methods, techniques, tools, and
methodologies to allow professionals of a given domain
to master domains in which they are not professionals
[
          <xref ref-type="bibr" rid="ref1 ref2 ref3 ref4">1-4</xref>
          ]. In the IoT context, we developed EFESTO-5W, a
platform implementing an EUD approach to customize
and synchronize the behavior of resources, like smart
objects and Web services, through
Event-ConditionActions (ECA) rules [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ]. With respect to other
TaskAutomation Systems (TASs) (see, for example, those in
[
          <xref ref-type="bibr" rid="ref6">6</xref>
          ]), whose adopted graphical notations often do not
match the mental model of most users [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ], EFESTO-5W
promotes a richer set of high-level abstractions and
operators to define rules and a visual notation that,
despite the intrinsic complexity related to managing
events and actions, is affordable even by
nonprogrammers.
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>TASs are typically conceived as general purpose</title>
        <p>
          systems, but their generality often implies a scarce
adoption by specific communities of end users [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ].
EFESTO-5W is also general purpose but can be
customized to several application domains. Our
position, which also derives from observing people
adopting our EUD tools during field studies, is that
these disadvantages occur because the proposed
platforms are too “general”, claiming that one single
design might satisfy the requirements of many
domains. For example, in Cultural Heritage (CH),
guides and curators are non-professional in Computer
Science who might create objects that visitors of CH
sites can bring with themselves, touch and manipulate
for experiencing the site by receiving personalized
information. However, by observing CH experts
engaged in the definition of smart objects behavior, we
realized that, even without being required to write any
code, it is still difficult for them to manage technical
concepts. We, therefore, propose higher-level
abstractions to allow end users themselves (i.e., CH
experts in the case study proposed in this paper) to
define custom properties to characterize the semantics
of smart objects, thus helping them to make sense of
the available smart devices and digital resources and
facilitate the definition of their cross interactions. These
features have been implemented in EFESTO-SE, an
extension of EFESTO-5W, which was evaluated
involving 14 professional cultural-heritage guides who
were asked to create an interactive visit experience.
The study showed that our hypotheses on extending
the semantics of smart objects by means of custom
attributes were valid with respect to the expectations of
CH stakeholders. We are further exploring and verifying
this aspect in some recently undertaken research
activities. In particular, we are interested in evaluating
if our proposal can stimulate the creativity of CH
stakeholder as smart-experience designers: the
hypothesis is that if the smart objects make evident the
relationship they have with the content, CH
professionals can better identify how to adopt such
devices to convey the CH-site content to visitors.
This paper is organized as follows. The next section
describes, with the help of a usage scenario, the
challenges of defining a smart interactive experience
and how our approach addresses them. The last section
concludes the paper and suggests some research issues
that would matter to further discuss at the workshop.
        </p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>Smart Experiences in the CH domain</title>
      <p>
        Even in the CH domain, IoT research has primarily
focused on technical features, e.g., how to program
networks of sensors and actuators and how to ensure
their interoperability [
        <xref ref-type="bibr" rid="ref10 ref11 ref12 ref9">9-12</xref>
        ]. Very few approaches try to
facilitate the configuration of smart objects and their
advantage is limited to programming single objects that
the visitors bring across the CH site to receive
personalized content when they reach hot spots [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. It
is still hard for CH experts (e.g., site curators and
professional guides) to synchronize the behavior of
multiple devices in order to create smart visit
experiences where different sensors and actuators,
installed in the environment or embedded in tangible
objects manipulated by visitors, actively react to some
detected events.
      </p>
      <p>In our ongoing research, we are investigating how
nontechnical users, like CH guides, can personalize the
behavior of smart objects in order to customize visit
experiences depending on their skills and capabilities,
as well as on the needs of specific visitors. To
understand how ECA rules can be exploited to define
smart visit experiences, let us consider the scenario
described in the following section.
1 Near-field communication device, resembling an ancient Roman
coin, used for identifying each visitor.</p>
      <sec id="sec-3-1">
        <title>A usage scenario</title>
        <p>Molly is the CH guide of the archaeological park of
Egnathia, an ancient Roman city in Southern Italy.
After the outdoor visit through the ruins, where Molly
explains the history of the city and illustrates the
function of every place in the park, the visit continues
in the park museum. Molly engages visitors in playing a
serious game in the “smart” rooms of the museum.
Here, display cases containing ancient objects are
instrumented with sensors able to detect NFC coins1
provided to each visitor before the game starts. During
the game, Molly asks different questions and,
accordingly, sets the sensors of the display cases in
different modalities by means of an app installed on her
smartphone. For example, she sets the “Age” modality
and asks visitors to find the display cases where Roman
objects are shown. The visitors move through the
museum, identify the cases matching Molly’s request
and touch them with their coin. If they are successful,
the light inside cases turns green and the visitor’s
current score is increased. Then, Molly asks other
questions and sets the display cases in the
corresponding modality, thus the game continues. The
synchronizations between cases and NFC coins are
established by the guide using our platform through the
creation of ECA rules.</p>
        <p>Defining the smart visit experience
From the previous scenario, it is evident that the
personalization of a smart visit experience might not be
limited to a trivial synchronization of smart objects, but
it might also require creating digital narratives threads
that professionals themselves need to put in context
with respect to the CH-site content. Driven by these
emerging requirements, we introduce the notion of
custom attributes, as a means to characterize smart
objects not only by native events and actions (as
conceived in many IoT platforms) but also by properties
that the domain experts (i.e., the designers of the
smart experience) can define to assign semantics to the
objects. Such semantics empowers and simplifies the
creation of ECA rules, as it can exploit an enriched
vocabulary based on user-defined terms. Visual
mechanisms also simplify the creation of custom
attributes and their association to smart objects.
To understand some of the advantages of custom
attributes, let us go back to the above scenario. Since
the CH guide needs to define, for each display case,
couplings with the NFC coins, she has to create a rule
for each coupling. In addition, such rules refer to
technical terminology (e.g., the NFC-coin code) that
does not correspond to the language adopted by the
domain experts. Figure 1 illustrates an example of ECA
rule that defines the synchronization between a single
case (i.e. case 3) and a specific coin. Thus, Molly has to
replicate this rule for coupling all the other cases and
coins.
In our proposal, before creating ECA rules, Molly
interacts with a visual tool offered by our platform,
which allows her to assign custom attributes to each
case by manipulating widget interfaces, without the
need of coding. Custom attributes can be seen as
conceptual tools that can allow designers to
characterize the basic elements of a smart experience
(i.e., smart objects and rules) with a semantics related
to the content to be conveyed during the smart
experience.</p>
        <p>In the example of Figure 2, she defines and assigns the
attributes Age, representing the age of the artifacts
contained by the cases, Points, representing the
number of points the visitor gains if the answer is
correct, Blinking time, indicating for how many seconds
the case has to blink. From now on, the creation of ECA
rules can exploit this terminology (see for example
Figure 3). In addition, more general rules, i.e.,
parametric, can be created. In Molly’s scenario, she
does not need to define a multitude of very similar
rules for coupling every single case and coin, since they
are all encompassed by the single rule shown in Figure
3.</p>
      </sec>
      <sec id="sec-3-2">
        <title>Evaluation with CH Guides</title>
        <p>We recruited 14 professional guides (5 female) aged
between 18 and 50 (x̅ = 37.9, SD = 8.2), operating in
different museums, archaeological sites and natural
parks in Southern Italy. The guides, who participated
individually and underwent the same procedure, were
required to design a smart visit experience.</p>
        <sec id="sec-3-2-1">
          <title>We collected different qualitative data. All the</title>
          <p>
            interactions were audio-video recorded by using an
external camera. To evaluate user satisfaction, a
questionnaire with 23 statements was administered at
the end of the study. The first statement was the Net
Promoter Score (NPS) question [14], typically used to
measure, on a scale between 0 and 10, how likely users
would recommend the product to a friend or a
colleague. The NPS score is equal to 57, i.e., excellent;
it indicates an attitude towards suggesting this system
to other CH guides. This encouraging result is also
confirmed by the analysis of the SUS questions, which
gave us detailed indications about the perceived system
usability and learnability. The SUS global score
was 81.1/100 (SD = 14.1), which is higher than the
average SUS scores (69.5) computed based on one
thousand studies reported in [
            <xref ref-type="bibr" rid="ref14">15</xref>
            ].
          </p>
          <p>The thematic analysis carried out on the transcribed
data, triangulated with the questionnaire results,
allowed us to identify important themes, also
highlighting the presence of some usability issues to be
addressed. We summarize them in the following
section, since we are confident that they would enable
further discussion at the workshop.</p>
        </sec>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Discussion and conclusions</title>
      <p>This article has presented our perspective on the EUD
of smart experiences. The work described here provides
the first results of a larger research that aims to
promote smart objects as components of a smart
experience that can bring with themselves evident
connections with the semantics of content for which
they facilitate the access. We showed how we extended
and customized a generic composition paradigm,
initially conceived for the EUD of IoT systems, to
respond to the need of exploiting IoT to mediate
narrative and content-appropriation goals for
interactive visits to CH sites. However, some challenges
are still open. We summarize them in the following with
the aim of stimulating discussion among the workshop
participants. Even though the reported aspects
emerged from the application of our EUD paradigm to
the CH domain, we believe they can be of general
validity and should be taken into account when defining
EUD frameworks for IoT also in other domains.
Constraining the flow of design activities. Based
on the observed problems and participants’
suggestions, we believe that our environment for the
creation of smart experiences should be redesigned to
provide a robust guidance to users. For example, a
wizard procedure can guide users in configuring an
initial, limited core set of smart objects, together with
their CAs and basic ECA rules controlling them. Later,
users can freely continue expanding this core set until
obtaining the final and complete smart experience.</p>
    </sec>
    <sec id="sec-5">
      <title>Simplifying the paradigm for CA definition. As</title>
      <p>emerged from triangulating questionnaire results with
users’ comments, CA definition resulted more difficult
2 http://microduinoinc.com/products/mcookie/
than ECA rules creation. Other metaphors for the
property assignment, than the one we implemented in
EFESTO-SE, could be perceived as more usable. For
example, one participant suggested a
spreadsheetbased solution: users could use a tabular format in
which they allocate smart objects in rows, CA names in
columns, and then specify CA values in cells located at
the intersection between rows and columns. The
tabular format was also adopted in the elicitation study
by the CH guides to specify CAs and their values.</p>
    </sec>
    <sec id="sec-6">
      <title>Stimulating creativity in smart-experience design.</title>
      <p>Another important aspect in smart-experience design is
the adoption of paradigms that can stimulate creativity.
The evaluation study demonstrated that EFESTO-SE
has a potential in supporting the design of smart
experiences. However, discussions with participants
revealed that there is still room for improvements.</p>
    </sec>
    <sec id="sec-7">
      <title>Supporting and fostering technical skills growth.</title>
      <p>Another aspect emerged during the discussion with the
CH experts regards the customization activities that go
beyond the smart-object programming supported by
EFESTO-SE. Indeed, 6 out of 14 participants stated
that, after a certain period of EFESTO-SE usage, they
would like to be supported in extending the smart
object capabilities by integrating new sensors and
actuators, avoiding to involve every time IT experts.
Even if this activity seems an aspect that only
technicians can accomplish, today there are hardware
and software solutions that satisfy this goal. For
example, mCookies2 is an alternative to Arduino that
can support people who have an interest in the “Do It
Yourself” paradigm for electronics. It consists of a set</p>
    </sec>
  </body>
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