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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>A framework to support multiple levels of interaction</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Dario Di Mauro dario.dimauro@unina.it</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Information Technology and Electrical Engineering PhD in Information Technology and Electrical Engineering Coordinator: prof. Daniele Riccio Tutor: prof. Francesco Cutugno University of Naples \Federico II"</institution>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2015</year>
      </pub-date>
      <fpage>25</fpage>
      <lpage>33</lpage>
      <abstract>
        <p>The human world is more and more inter-connected and, as consequence, we need to communicate in a faster and smarted way. Many software applications do that, but they usually work in a single context at time. In this paper we present a framework that aims at making the interaction easier and more natural; involved actors are connected in a graph, sending and receiving signals by adjacent nodes. The framework has been developed to work in di erent contexts, especially in domotic and cultural heritage fruition; the goal is to connect di erent spaces, such as homes, museums, etc, focusing the attention on interaction perspective, maintaining a natural interface for the user and hiding low-level communication issues. This work will be framed in the context of Natural User Interfaces, so it is centered on the user, exchanging signals with external sensors or devices, such as a smartphone and PC, using gestures, dialogues and augmented reality.</p>
      </abstract>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>Introduction</title>
      <p>The human world is more and more inter-connected and, as a consequence, we
need to communicate in a faster and smarter way. We want to talk with friends,
require information, enjoy a work of art, interact with appliances and live real
life. Many softwares and apps do that, but can we develop a general interaction
system, composing di erent communications channels in a single environment?
Could we create a mixed reality in which the perceived world is extended and
fused with a virtual and interactive one, as more naturally and transparently as
possible?</p>
      <p>Progresses in HCI have changed the type of interaction between humans and
computers. Advances in HCI make the interaction faster and simpler, but a lot
of work still needs to be done. With the introduction of smart sensors,
lowcost hardware and powerful smartphones, smart-homes were born, interactive
museums are going to grow, human-robot interaction is going to be more complex
but all of them are treated as di erent spaces. The present is this, the future
could be the connection among these worlds. The cited contexts are clearly</p>
      <p>di erent, but they could share some interaction ingredients: the exchange of
signals and information, for example, or the need to present enough data to
handle a communication between humans and machines, without loading too
much the interface.</p>
      <p>The goal of this PhD thesis/project is to develop a framework that makes
easier the communication among cited sensors and actors, managing in the same
graph of connections all the parts and activating the essential nodes in the right
moment. As you will read in the next sections, the theoretical framework in
which this goal will be framed is that of Natural User Interfaces. Due to the
recent beginning of this PhD, both the general concept and single modules are
in phase of de nition. Some parts of this paper, therefore, could require further
arrangements in the next future.</p>
      <p>This paper is organized as follows: section 2 summarizes the starting point
and related works; section 3 explains the proposed framework. Section 4 reports
preliminary results about technologies that will be included in the framework;
section 6 concludes the work.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Related Works</title>
      <p>
        This work takes ideas from many previously published contributions: a similar
framework is presented in [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ]. That system synchronizes and records di erent
signals in order to recognize human emotions; considered sensors are a
microphone, a webcam and a wiimote. The proposed work starts from this concept
relying on the synchronization module but, instead of just analyze the signals,
it processes them to produce an output, introducing an interaction with other
systems. The motivation about this work is in the emerging interests in social
signal processing, a new cross-disciplinary research domain that aims at
understanding and modeling social interactions and providing computer with similar
abilities [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ][
        <xref ref-type="bibr" rid="ref15">15</xref>
        ].
      </p>
      <p>
        By interacting with a user, a part of the system will be devoted to analyze
implicit feedback from her. This approach is useful helping to do a
recommendation [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ] or to better understand a user's preference, without asking her an
explicit question [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ].
      </p>
      <p>
        Due to the main context of the work, a large part of the work will be
devoted to an high-level interaction, based on gestures, augmented reality, dialog
systems and 3D audio; this choice aims at making the interaction natural and
e ective. The cited channels are not new in literature: gesture-based interaction
is extensively adopted [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]; regarding 3D audio, a large number of systems has
been presented [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ][
        <xref ref-type="bibr" rid="ref5">5</xref>
        ][
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]; usually they limit themself to a 3D audio production
but a more interactive and social approach misses. The state of the art about
dialog systems could be represented by OpenDial [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ]. This system will be used
as dialog engine.
Proc. of CHItaly 2015 Doctoral Consortium, Rome (Italy), September 28th 2015 (published at http://ceur-ws.org).
Copyright © 2015 for the individual papers by the papers' authors. Copying permitted for private and academic purposes.
This volume is published and copyrighted by its editors.
      </p>
    </sec>
    <sec id="sec-3">
      <title>Proposed Approach</title>
      <p>As announced in section 1, this PhD project aims at developing a framework
that simpli es the communication among di erent agents. The work is based on
the concept that the same framework can be used in di erent scenarios, so the
system abstracts from the gure of agents: they can be humans, robots,
smartdevices or works of art, for example. They need to interact each other: not-human
agents need to communicate by packets; if at least an agent is a human, instead,
a di erent channel is needed. Regarding the presentation of data, a remarkable
attention has been oriented on the naturalness of the interaction; in some cases,
for example, an interaction based on voices, gestures and expressions can be
more e ective than a text-based one. In the work a modular architecture has
been designed, separating the communication and synchronization modules from
the dialog manager and the presentation layers.</p>
      <p>
        The work is in the context of the Natural User Interfaces (NUI) [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ], so it
aims at making an interaction as more natural as possible, always centered on
the user. The use of the proposed framework is oriented to a non-expert user
that need an high-level interaction; the system hides low-level issues to cited
user, focusing herself on interaction perspective.
      </p>
      <p>In a connected world, a wide range of sensors should be distributed in the
environment. Nowadays, a lot of high-level sensors are low-cost, such as Microsoft
Kinect. A single kinect manages a set of users, tracking their skeletons and joints,
but in a limited eld of view. An array of kinects covers a large part of space,
as a room, giving the possibility to track users and moving objects in a wider
range and with di erent orientations. Other kinect-like sensor could be used,
but they have not been considered yet. The introduced framework manages
di erent sensors, synchronizing them and combining the ows in a single engine.
A recognition module processes this input and extracts gestures information,
communicating them to other agents. The same system produces an output,
with a bidirectional interaction.
3.1</p>
      <sec id="sec-3-1">
        <title>The framework engine</title>
        <p>The core of the system manages a graph in which the nodes are the agents
and the arches are direct connections among the agents. Each node has data,
requires signals or produces them. An agent communicates with adjacent nodes;
it receives inputs from them and produces an output recurring to local abilities
or information. As explained above, NUI is the general frame of the work, so a
vocal dialog could be a chosen type of interaction; for example, a node receives a
vocal input, uses local structures to recognize it and to prepare an utterance or
other possible outputs, such as expressions, and recurs to Text-To-Speech (TTS)
to talk with others. In a more complex scenario, the framework could support
a natural interaction between a human and a virtual assistant and, at the same
time, a communication between the assistant and other sensors or actuators.</p>
        <p>Because of the nature of interaction, graph connections could change, so ow
optimization problem will raise. Given the nature of this framework, di erent
Proc. of CHItaly 2015 Doctoral Consortium, Rome (Italy), September 28th 2015 (published at http://ceur-ws.org).
Copyright © 2015 for the individual papers by the papers' authors. Copying permitted for private and academic purposes.
This volume is published and copyrighted by its editors.</p>
        <p>signals should be managed and analyzed together. The system includes a
multimodal processing block that synchronizes, links and makes readable signals to
selected agents.
3.2</p>
      </sec>
      <sec id="sec-3-2">
        <title>Interaction Analysis</title>
        <p>
          As a control system requires to analyze the e ects of the output on the world, an
interaction framework may require to study the user's feedback in order to obtain
a more e ective interaction. It is possible, in a fused engine, to track a user's
actions in di erent contexts; these information are very useful for a widespread
analysis. The presented framework is born to be applied in di erent settings
trying to connect them, so an extended data analysis system can be provided;
type of data are user's position, choices, preferences or personal information.
The work aims at providing an integration with external modules, devoted to
the analysis of listed signals. An example of behaviour analysis is navigation in
indoor environment as o ces [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ] or museums [
          <xref ref-type="bibr" rid="ref2">2</xref>
          ].
        </p>
        <p>
          In the framework, an integration with the analysis of routines, such as [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ], or
an user's pro ling [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ] or an implicit feedback analysis module [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ] will be
considered. Di erent solution will be proposed in heterogeneous scenarios, depending
on types of signals and interaction: cultural heritage fruition and domotic will
be sample contexts. Due to the similarity of coped issues with [
          <xref ref-type="bibr" rid="ref3">3</xref>
          ], domain
developers and maieuta designer will be involved in the system creation, especially
for the scenario of cultural heritage fruition.
3.3
        </p>
      </sec>
      <sec id="sec-3-3">
        <title>Natural Interfaces</title>
        <p>As explained, the framework will work on di erent levels of abstraction.
Regarding high-level interaction, the system will support gesture recognition,
augmented reality or dialog modules; these modules could be used to interact with
other agents. Figure 1 reports an instance of the proposed idea: in the example,
two distinct environments, home and museum, that are going to be connected.</p>
        <p>User 1 usually interacts with a Co ee machine, a Smart TV and sometimes goes
to the museum. With the use of the presented framework, User 1 could use a
smart audio-guide at the museum - details about it are later in this section.</p>
        <p>She expresses preferences about some pieces of art and a theoretical pro ling
system shares with the user a sketch about her. Once she is at home, the Smart
TV could use the obtained \cultural pro le" and possibly recommend cultural
channels; the user could change the recommendation interacting by gestures.</p>
        <p>The same user, every morning, takes a co ee at 8:00. The smart co ee machine
could learn this routine and power-on itself at 7:30, optimizing bene ts and
energy consumption for example; considering the co ee stocks, the machine could
estimate when other co ee needs to be bought.</p>
        <p>
          In the proposed example, the user has been interacted with an audio-guide,
a smart TV and a co ee machine; many information has been moved, but the
framework, working behind all the agents, has hidden this fact. Some of them
has been developed in other projects, such as audio augmented reality based on
Proc. of CHItaly 2015 Doctoral Consortium, Rome (Italy), September 28th 2015 (published at http://ceur-ws.org).
Copyright © 2015 for the individual papers by the papers' authors. Copying permitted for private and academic purposes.
This volume is published and copyrighted by its editors.
3D audio. For privacy reasons, the user can always step in the actions and she
has a noti cation as sensible data are transmitted.
3D Audio Interaction Sound spatiality carries more information than simple
stereo audio [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ]; by simulating the human hearing, an interaction based on 3D
Audio has been tested [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ]. Audio-augmented reality is a method to enrich the
real world with virtual sounds in a given context and, setting aside the visual
interaction, we limit as more as possible obstacles between listener and real life.
        </p>
        <p>The system is an interactive audio-guide developed as an Android app called
Caruso. As embryonic phase, Caruso works in a limited area in the historic
center of Naples, giving information about historical buildings and churches of
that area. As the user is close to a Point Of Interest (POI), a virtual soundscape
with a 3D sound composition starts. The stage is dynamic: Caruso follows the
user's movements, changing sound's direction basing on listener's position and
orientation.</p>
        <p>
          In order to make the interaction as more natural as possible, smart
headphones has been designed. These headphones are equipped with dedicated
circuits and detects the orientation of the head in the space. A Bluetooth module
communicates the orientation to the smartphone; the 3D scene is updated as
the angles change. Figure 2 reports a test of Caruso during a test session for the
Or.C.He.S.T.R.A. project (www.orchestrasmartnapoli.it).
Proc. of CHItaly 2015 Doctoral Consortium, Rome (Italy), September 28th 2015 (published at http://ceur-ws.org).
Copyright © 2015 for the individual papers by the papers' authors. Copying permitted for private and academic purposes.
This volume is published and copyrighted by its editors.
This PhD started in November 2014 and, at now, the framework proposed in
section 3 is in design phase. No wide experiments has been conducted; preliminary
results about 3D sound interaction has been collected. The 3D Audio Augmented
Interaction has been tested in a realistic context, with an interactive audio-guide
with 3D sounds [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ].
        </p>
        <p>An interactive audio-guide: As presented in section 3.3, Caruso has been
used as a audio-guide in the historical center of Naples in the experimental
process of the Or.C.He.S.T.R.A. project. Figure 3 shows the proposed POIs.
Proc. of CHItaly 2015 Doctoral Consortium, Rome (Italy), September 28th 2015 (published at http://ceur-ws.org).
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This volume is published and copyrighted by its editors.</p>
        <p>The test consists of 8 POIs, composing a path in the historic center of Naples;
the proposed path is usually routed by tourists and citizens. Each POI proposes
a soundscape in 3D sound, talking about anecdotes and historic personalities.</p>
        <p>The estimated duration of the visit is about 20 minutes: it includes the duration
of each scene and the distance between POIs.</p>
        <p>All the scenes have been prepared and recorded by experts people. 32
participants attended the test. They borrowed smartphone and smart headphones
and, with poor information about the goal of the test, have gone around. As they
pass close to a POI, the soundscape starts automatically, by detecting Bluetooth
Low Energy antennas, known as beacons. 16 testers used a version of the app
without any global information about the POI distribution. For the other 16, we
added the map in gure 3. A blue point showed the user's position.</p>
        <p>Just a very small part of the attendees discovered all the POIs, about 10%.</p>
        <p>Motivations about that are searchable in:
{ the participants has no limits of time in the use of Caruso and a large part</p>
        <p>of them just wanted to try a new technology;
{ the same people contributed to other tests, so they did not dedicate all the</p>
        <p>free time to Caruso;
{ the goal of the experimentation was not to nd all POIs, but to receive a
feedback about the proposed interaction system.</p>
        <p>Everybody except one person noted the advantages of 3D sounds in the
cultural heritage fruition; the use of this channel of interaction and the dynamism
of the scene o er a very involving experience. The use of smart headphones
improves the transparency of the interface: the listener takes part of the soundscape
as an actress, virtually occupying a place in the listened scene and without the
need to insert the code of a POI; this is a very di erent situation compared with
traditional audio-guide, in which the sound is static and the user must detract
the attention from the cultural context to start a new one. Eventually the map
has been very useful for tourists; it o ers a global reference in the environment,
giving the possibility to plan paths to the Points Of Interest.
5</p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>Acknowledgment</title>
      <p>The 3D Audio Augmented Interaction has been funded by the European
Community and the Italian Ministry of University and Research and EU as part of
the PON Or.C.He.S.T.R.A. project.
6</p>
    </sec>
    <sec id="sec-5">
      <title>Conclusions</title>
      <p>This paper presented a framework that aims at making the interaction smarter,
simplifying it among more agents, in di erent contexts, mainly focusing the
attention on the human perspective in the communication. The framework is
designed in multiple layers managing low-level signals, dialogues and high-level
Proc. of CHItaly 2015 Doctoral Consortium, Rome (Italy), September 28th 2015 (published at http://ceur-ws.org).
Copyright © 2015 for the individual papers by the papers' authors. Copying permitted for private and academic purposes.
This volume is published and copyrighted by its editors.</p>
      <p>interaction, based on voices, gestures and augmented reality. The presented
framework is in a design phase, but separate modules already exists: the
audioaugmented reality based on 3D sounds has been applied in di erent contexts, a
suitable gesture recognition module is in developing. Coming work will be
devoted to the framework itself, choosing di erent case studies in cited scenarios:
domotic and cultural heritage fruition; other contexts will be considered.
Proc. of CHItaly 2015 Doctoral Consortium, Rome (Italy), September 28th 2015 (published at http://ceur-ws.org).
Copyright © 2015 for the individual papers by the papers' authors. Copying permitted for private and academic purposes.
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    </sec>
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