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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Digital Ecosystem Model for the Production of Mixed Reality Environments to Assist Senile Dementia Patients</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Erwin B. Montes-Chaparro</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Jaime Muñoz-Arteaga</string-name>
          <email>jaime.munoz@edu.uaa.mx</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Angel E. Muñoz-Zavala</string-name>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Miguel A. Ortiz-Esparza</string-name>
          <email>miguel.ortiz@cimat.mx</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>940</institution>
          ,
          <addr-line>Ciudad Universitaria, C.P. 20100, Aguascalientes, Ags.</addr-line>
          <country country="MX">México</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Center for Research in Mathematics</institution>
          ,
          <addr-line>Quantum Knowledge City, 98160, Zacatecas</addr-line>
          ,
          <country country="MX">Mexico</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>Universidad Autónoma de Aguascalientes</institution>
          ,
          <addr-line>Av. Universidad</addr-line>
        </aff>
      </contrib-group>
      <abstract>
        <p>Senile dementia is one of the most common sufferings in the elderly population as brain functions start to deteriorate, making their day-to-day routine increasingly dependent on care staff. We need to build rapport between the Elderly and technology tools to allow aged people have an easier way to complete daily tasks without losing their independence and allowing them to work out to maintain their health and mobility with as less intervention with rehab staff as possible via remote monitoring using Internet of Things to detect anomalies in the elderly daily routine to prevent other age-related diseases in an early stage. This article proposes an elderly assistance ecosystem with focus on senile dementia using IoT and applying Software Engineering for the architecture design side allowing to make a more detailed and suited implementation.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;Mixed Reality</kwd>
        <kwd>Internet of Things</kwd>
        <kwd>Senile Dementia</kwd>
        <kwd>UX</kwd>
        <kwd>Digital Ecosystem 1</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Despite the Technological advances being adopted by more people every time [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], often, the
Elderly population, (Baby boomers and older generations) never had the opportunity of living
the Technological evolution in an active way.
      </p>
      <p>
        Most modern technology corporations do not design products for the elder users daily living,
not to mention ease of use of Graphic User Interfaces (GUI) for them, making it harder to adopt
modern gadgets and devices that could make their life easier [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Elderly people need to be
trained when they are not familiar with modern tech devices, and the way to let elder people
learn by themselves is designing interfaces as simple as possible but with the generational breach
in mind so they can use new technology with a minimal assistance, as they are not known for
being technologically enthusiastic [
        <xref ref-type="bibr" rid="ref1 ref3">1,3</xref>
        ].
      </p>
      <p>
        Elder people could develop a low self-esteem after retirement because of the contrast with
their new daily routine, diminishing their physical and social activity to a large degree. All persons
in retirement should maintain their dignity and the right to be useful; the users should be able to
discover his own limitations and capacities. The Quality of life concept is nearly linked to social,
mental and physical wellbeing [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
      </p>
      <p>
        Senile dementia is known for being in the top 3 causes of death in the elderly, just after cancer
and hearth diseases [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], but it is feasible to lower the repercussions in mental health using the
benefits of aerobic exercises [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]; this, in combination with virtual environments specially
designed for the elderly physical activity, has demonstrated an increasing interest in workout
routines because of their null or low social interaction with other persons, increasing the
cognitive stimulation [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ].
      </p>
      <p>
        As technology has a big presence in our daily routine, and it has been an important part of our
entire lives, in a direct or indirect way. The younger generations are able to adapt quickly to
technology created to be friendly and intuitive for almost any user. User Experience (UX) is an
almost new knowledge area in the modern devices and applications development; there are
notable changes among device generations and their interactions with users. There is an evident
good UX design in the field of Smart Assistants (Google Assistant, Amazon Alexa, etc.) allowing
recognition of multiple accents in a language, the fulfillment for users is prominent [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
      </p>
      <p>This work has been formed in seven sections: Second section, named Background, contains
basic definitions of the technologies related, Third section contains some work with VR devices
for treating senile dementia patients, Fourth section contains the problem outline, with other
works using the integrated technologies of this approach, Fifth section describes a Digital
Ecosystem Model for the development of Mixed Reality Environments, showing a general
architecture for possible scenarios and organizing the model by interaction layers in order to
assist the patients with senile dementia; A case study is presented in section six, applying several
technologies in a real scenario. Finally, the conclusions are described in section seven.</p>
    </sec>
    <sec id="sec-2">
      <title>2. Background</title>
      <p>
        VR, also known as virtual environments, consists in an ambience surrounding a person with
sound and images that can that transmit the feel of being present physically in that virtual
environment [8]. Thanks to the versatility of current Game engines, Virtual Environments
development can be very straightforward compared to some Game engine generations ago,
making them reliable tools to enhance UX in combination with the daily routine [
        <xref ref-type="bibr" rid="ref3">3,8,9</xref>
        ]. The use
of Virtual Environments in Social Interaction has a promising future supporting education,
decision making simulation, training, health and clinical practices [10], allowing innovative
techniques to communicate ideas.
      </p>
      <p>Augmented Reality (AR) refers to a set of technologies that permit the users seeing most of the
real environment surrounding them through a device capable of adding extra graphical
information over real objects, adding virtual layers to the real environment view. AR can make
some activities easier for people applied to the daily life, by highlighting objects with colors or
showing notifications.</p>
      <p>Mixed Reality (MR), as shown in Figure 1, consists in a combination of real objects and the
interaction with virtual ones, giving the ability of using corporeal objects with 3D objects
rendered on a MR headset [11]. The use of physical peripherals can be more adequate for elder
users, making them feel comfortable with the feedback found in the haptic vibration.</p>
      <p>The current electronic miniaturization techniques allow the production of reliable and
powerful mobile microcomputers as the Raspberry Pi, being the perfect choice for reliable
devices to be the brain unit for custom and open-source home automation systems [12] to control
different electronic devices as sensors, electric motors and actuators with Arduino as low-level
hardware interface.</p>
      <p>The concept of Digital Ecosystem can be defined as loose networks of interacting organization
that are digitally connected and enabled by modularity, and that affect and are affected by each
other’s offering [14], in this way, a digital ecosystem can be integrated by the interaction among
Internet of Things, Virtual Environments, AR/VR headsets, Wearable devices, using Smartphones,
Tablets and Smart Assistants as intermediaries with the elder patient.</p>
    </sec>
    <sec id="sec-3">
      <title>3. Related Work</title>
      <p>
        The use of AR/VR applied to Senile Dementia is an almost new area in the treatment of Mental
Diseases. Due the cost reduction in Virtual reality headsets and the increase in power for mobile
devices, VR applications have become affordable for more people like ever before.
The creation of virtual environments experience have had an exponential growth combining
modern engines engines like Unity [
        <xref ref-type="bibr" rid="ref3 ref5">3,5,9</xref>
        ] (free of charge for non-commercial applications) and
Mobile phones with AR/VR accessories as cardboard (Figure 2), letting users not aware of virtual
environments get a taste of Mixed reality technology and developers to create experimental
AR/VR oriented apps relatively free of charge.
      </p>
      <p>Since 2012 a growth in the VR apps for dementia had been noticed [15] without the necessity of
taking the patients out of the nursing home allows to explore a great variety of scenarios and
study the reaction of the elders to virtual nature environments as a forest [8]. A proposal of an
adaptive VR environment can be found, using Real-Time feedback from the user to change what
the user can see and interact with and monitor brain activity [9].</p>
      <p>
        The combination of Virtual environments and work out allow the elderly to avoid routine and
“visit” (in a virtual way) other places outside the asylum they live in [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ], giving positive feedback
by users, expressing they want to work out for longer times; this work focuses on a virtual
environment using Unity and part of hardware design adapting an arm and leg exerciser machine.
      </p>
      <p>Diseases as Alzheimer’s have promising results when combining Virtual Reality [16] showing
the benefits of a tight integration with MR and theoretical models [17] using reminiscence
therapy.</p>
      <p>Project CogARC [18] integrates real objects with AR add-ons and a visual detection software
installed on a tablet for the elder patient to play small games; even when they obtained positive
results, in the part of negative feedback shows that the interactive aspects for some games have
some flaws.</p>
      <p>
        HalleyAssist [19] uses a complex ecosystem trying to prevent the majority of elder patient’s
health related ailments combining sensor sets to achieve a better detection of anomalies in
movement according to patterns stored in the knowledge base; on the other side, this work leaves
the software and user interface design to make easier for the elder to adopt this kind of devices
and applications for their day-to-day living [
        <xref ref-type="bibr" rid="ref2 ref3 ref5">2,3,5</xref>
        ].
      </p>
      <p>
        Microsoft HoloLens, as a MR headset [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] has demonstrated being a great optimal device with
memory loss patients including a wide range of media content available. Panoramic video
experiences in 360° show better attention of the patients, but interface design is needed
especially for elderly users, not to mention that bad device calibration can cause dizziness (digital
point-of-view strain and motion sickness).
      </p>
      <p>
        DCPAR project [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ] uses a combination of a pico-projector hanging around the neck and a tablet
app for the user. The users had problems with the weight and bulkiness of the pico-projector
around the neck despite having a good tablet app design and the good response of the elder users.
      </p>
      <p>Eldergames Project has a MR environment with Tabletop games in it, this to train cognitive
functions [11]; this work deepens in the emotional aspects of the player interactions with each
other, having positive results and proving that a good design in UX for elder patients is feasible.</p>
    </sec>
    <sec id="sec-4">
      <title>4. Problem Outline</title>
      <p>
        Several areas of opportunity can be found when talking about MR applied to Elderly patients:
• Mobility issues: one of the most frequent ailing in the elder population caused by
muscular, cardiovascular, metabolism and brain deterioration related to age [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]; some
brain diseases symptoms are known for its delay with age with the integration of
exercise routines. This work is in search of elders doing constant physical activity to
maintain brain health, with the use of virtual environments and lightweight devices to
promote user engagement.
• Device ergonomics: Systems Design for occupational therapy [20] has shown good
results in motor rehabilitation using virtual environments and peripherals. Here is
where it lays the balance among ergonomics, intuitive interfaces, and pleasant
environments, to increase the elder user engagement, making therapy sessions
enjoyable.
• Software Engineering approach: Many of the research articles related to AR for the
Elderly have a practical approach, device functionality and experiment design
depending on the case scenario [
        <xref ref-type="bibr" rid="ref5">5,11,21</xref>
        ], with the software design part put aside.
      </p>
    </sec>
    <sec id="sec-5">
      <title>5. Digital Ecosystem Model</title>
      <p>The reason to define a digital ecosystem arquitecture is because of the presence of different
technologies interacting with each other using multiple communication protocols that could
produce confusion among all the kinds of devices connected [14]. The use of multiple distinct
environments will be required for the different patient scenarios, in this work the proposal
consist in a digital ecosystem architecture combining AR, VR, MR, and tools we can find in
software design like the Unified Modeling Language (UML) [22] and System Modeling Language
(SysML) [23], using the Human-Computer Interface [24] to adapt User Interfaces (UI) and User
Experience (UX).</p>
      <p>We are looking for a way to easily adapt to the most possible kinds of mental diseases starting
from a generic architecture and follow the evolution of the participants sufferings.</p>
      <sec id="sec-5-1">
        <title>5.1. Direct Interaction</title>
        <p>We define Direct Interaction as all the devices the patient can interact with in a physical way
(tablets, smartphones, AR/VR headsets, body-attached wearable devices), including biometric
sensors to monitor the heart rate, step counter with the help of a smartphone for fall detection
[25]. Some kinds of dementia can cause the patient to forget that is wearing a VR headset or any
other kind of wearable device, so the need of a non-intrusive gadget is a must to make the
experience comfortable for the elderly.</p>
        <p>Tablets and smartphones allow the elder users them to be aware of their own medical
situation and a medium to receive calls and notifications from relatives and care staff to maintain
a constant interpersonal contact, meanwhile the sensor set found in smartphones can register
accidental falls, movement patterns and daily activities for pattern analysis.</p>
        <p>AR/VR Headsets running routines in virtual environments will permit the patient to have
multiple therapies for physical workout, alternating the virtual scenario to make the experience
less monotonous.</p>
      </sec>
      <sec id="sec-5-2">
        <title>5.2. Indirect Interaction</title>
        <p>The area of Indirect interaction will be integrated by devices the patient can interact with and
connected to a server in the local network to process data locally. Usually, wearables have an
incredibly low processing, battery, and storage capacity, so a more powerful device is needed to
collect all the local information.</p>
        <p>
          Microcomputers like Raspberry Pi [12] have shown their powerful processors that can be used
for data readings from wearables and other monitoring local network devices as: cameras for
pattern recognition and live remote monitoring; smart assistants as Google Home or Alexa [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ]
for direct user feedback and requests using voice commands; room ambience monitoring to
record data and decide for making simple actions (air cooling systems, ceiling fans, etc.) or
notifications to the user in different temperature situations adjusting related devices as room
lights. After processing the basic patient situation, the Raspberry will connect to the Internet to
give live information to the care staff and the deploy of alerts in anomalous situations.
        </p>
        <p>In this layer of interaction, the patient can trigger simple commands in the voice Assistant to
change lights or even adjust the room temperature; in case these parameters are not dependent
of the patient, other near relatives can make the respective adjustments to the room control.</p>
      </sec>
      <sec id="sec-5-3">
        <title>5.3. Remote Interaction</title>
        <p>The remote interaction is made through the Internet connection, this is the way caring staff,
using audio and video, and distant relatives, using social network notifications, in a and can
maintain contact and monitor the elder patient, permitting them to know the status of their
physical situation and to make direct calls using the smart Assistant speaker or mobile devices.</p>
        <p>The medical staff can receive alerts when an anomaly is detected with the patient that is being
monitored and make audio calls directly to the mobile phone, tablet or smart assistant speaker
to give the patient feedback of their situation to immediately take actions.</p>
      </sec>
      <sec id="sec-5-4">
        <title>5.4. Data Analysis</title>
        <p>An encrypted connection is needed to protect all the data collected from patients when is
stored in the applications servers, where all the big data processing will be done. This is where
anomalies in the patient’s behavior can be detected following differences in the movement or
voice patterns, allowing to detect other diseases related to the Elderly in an early stage.</p>
        <p>Server infrastructure will be needed to host more users from different places, including
hospitals, nursing homes or the patient’s home and classify by type of disease and sufferings; this
will allow to detect anomalous patterns and early symptoms in patients that share the same
suffering. All the ecosystem server infrastructure needs to be ready to adopt methods for big data
processing and algorithms that will classify the data.</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>6. Case Study</title>
      <p>The target audiences are the elderly patients in public nursing homes that belong to the
“Integral Development for the Family” institute (DIF) in Aguascalientes, México. An interview
with the caring staff is necessary to study the elders work out routines, recreational activities,
sleeping schedule, main interests, other aging ailments not causally related to the Senile
Dementia, general user preferences, openness to using technological gadgets and wearable
devices, etc.</p>
      <p>The Mixed reality infrastructure scenario is showed in Figure 4 where we can show in more
detail the process of the information management and all the ways the care staff can receive the
information and monitor the patient.</p>
      <p>The Senile Dementia disease we are going to focus on is the Alzheimer’s disease [26], adapting
virtual environments with therapy techniques and follow the evolution of the patients
participating in the project. Adaptations to devices will be needed in case some patients have
physical or mental limitations, but the idea is to have the devices ready for the most possible
scenarios.</p>
      <sec id="sec-6-1">
        <title>6.1. Direct Interaction</title>
        <p>Xiaomi mi Band (Figure 5) is an especially useful wearable to monitor the steps per day and
the heart rate of the patient at a low cost with an acceptable reading quality for 15 to 40 USD and
with a great battery duration that is from one to three weeks depending on the generation of the
wearable and the features that are being used.</p>
        <p>A smartphone is needed for every single Mi Band device to store the data we can retrieve from
the patients via Bluetooth Connection. The Mi Band can collect data from one to two weeks until
the battery is completely depleted.</p>
        <p>The readings will give us an idea of how many steps the patient walks a day and adjust their
exercise routine when it is necessary. A simple heart rate monitor is integrated in the smart band
and could help the caring staff to have more frequent heart rate readings without visiting the
patient.</p>
        <p>For the first stage of the project the selected VR headset is the Oculus Rift (Figure. 6) as part
of the interface between the patient and the virtual environment. For further stages, the objective
is using the Cardboard (Figure 2) headset with a smartphone, as a low-cost VR headset and easy
to replicate in case the headset needs spare parts.</p>
      </sec>
      <sec id="sec-6-2">
        <title>6.2. Indirect Interaction</title>
        <p>
          Amazon Alexa and Google Home (Figure 7) are reliable voice-controlled Smart Assistants with
great cloud voice processing algorithms [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ] to give the user an almost immediate response to
commands using natural language. This device can give information for the patient about
weather, the clock, or their therapy schedule; also, this device can give the patients a virtual
interaction with the Smart assistance including asking for any kind of information, telling jokes,
playing voice games and solving riddles to make a more enjoyable routine for the patient.
        </p>
      </sec>
      <sec id="sec-6-3">
        <title>6.3. Remote Interaction</title>
        <p>Using APIs of the most popular Social Networks like Facebook, Instagram or X (aka Twitter)
or even some Instant Messaging applications like Telegram can send notifications to the
interested relatives and friends concerning the patient’s condition; in a similar way, medical staff
will receive special notifications but with biometric information instead of social network
interactions to know the status of the patient in a more real-time oriented communication.</p>
      </sec>
      <sec id="sec-6-4">
        <title>6.4. Data Analysis</title>
        <p>The first step for data analysis is to build a knowledge base with all the data collected from the
devices around the patient; with the data retrieved from all the patients’ routines for data mining
will be developed to detect patterns in the information using statistics and heuristics.</p>
        <p>In a further stage there will be a possibility to detect anomalies in movement and some
sufferings in an early phase, giving the medical staff the opportunity to treat diseases
opportunely.</p>
      </sec>
    </sec>
    <sec id="sec-7">
      <title>7. Conclusion</title>
      <p>The digital ecosystem modeling is a necessary part of the interconection of devices and the
type of interplay with the actors involved. Each device role is essential in the environment to
maintain a consistent connectivity between layers. Comprehend the specific case of each user will
permit us to have a wide view of the needs for the different kind of dementia present in the
elderly.</p>
      <p>Interactions between elder users and virtual environments though mixed reality can offer an
inmense expansion of the elderly’s daily social interaction without leaving their homes, allowing
elders to get out of the monotony and follow their daily therapy sessions in an easier way; the AR
part could help the elders to have a better perception of their home environment when being left
alone.</p>
      <p>The UX design will allow an increasing number of elder patients to have a more bearable
experience in rehabilitation and get out of the routine they live in the nursing homes. Virtual
environments are great tools with AR/VR Headsets altogether to achieve the users engagement
with the ecosystem. We need to present our elders the technologies they have been missing for
years, or even decades, to make their daily living a more enjoyable experience at a relative
lowcost and keeping their independence as much as possible.
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    </sec>
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