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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Context Aware Recommender Systems and Techniques in offering Smart Learning: A Survey and Future work</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Kevin Otieno Gogo,</string-name>
          <email>kevingogo2002@gmail.com</email>
          <xref ref-type="aff" rid="aff0">0</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Lawrence Nderu,</string-name>
          <email>lnderu@jkuat.ac.ke,</email>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Stephen Makau Mutua</string-name>
          <email>smutua@must.ac.ke</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Department of Computer Science, Chuka University</institution>
          ,
          <addr-line>Chuka</addr-line>
          ,
          <country country="KE">Kenya</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>School of Computing and Informatics, MUST University</institution>
          ,
          <addr-line>Meru</addr-line>
          ,
          <country country="KE">Kenya</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>School of Computing and Information Tech., JKUAT University</institution>
          ,
          <addr-line>Juja</addr-line>
          ,
          <country country="KE">Kenya</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>Abstract- There exist several context aware recommender systems (CARS) that have been designed to perform specific tasks in facilitating smart learning. Such context aware recommender systems have potentially played important roles in education, especially in recommending to a learner certain activities. In this research we reviewed existing context aware recommender systems used in facilitating pedagogical smart learning. Our survey paper addressed the following research questions; which contexts are used in smart learning, how the contexts are collected, recommended activities, data mining techniques, and future work in CARS for smart learning. In our findings we addressed the research questions with reference to smart learning. We identified that there are numerous context aware recommender systems; but despite all existing CARS in smart learning, there are several challenges and gaps that are still existing. Such challenges include: - Absence of CARS that perfectly fits the ever changing learner's needs and preferences, and lack of standard database for smart learning, among other issues highlighted in our future work.</p>
      </abstract>
      <kwd-group>
        <kwd />
        <kwd>Artificial intelligence</kwd>
        <kwd>Context aware recommender system</kwd>
        <kwd>Technology enabled Learning</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>I. INTRODUCTION</title>
      <p>
        Amassively huge educational content that has been
uthor [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ], [
        <xref ref-type="bibr" rid="ref25">25</xref>
        ], and [
        <xref ref-type="bibr" rid="ref40">40</xref>
        ], explain that there is
digitised in digital libraries and other learning platforms
globally. On contrary there are insufficient mechanisms put
in place to recommend relevant and personalized learning
content to learners. Specifically based on the learners’ ever
changing preferences, that we consider to be smart learning.
      </p>
      <p>
        Reference [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ], [
        <xref ref-type="bibr" rid="ref45">45</xref>
        ], and [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ], point out that context aware
systems collect a variety of information from their
environment and adapt their behavior according to the
collected data. The collected bits of information is what the
system interprets into a meaningful action, based on the
current status of the entities that interact with the system.
Context information that the system collects could refer and
not limited to identity, time, temperature, mood, location,
activity, environment, etc. In order to recommend relevant
learning content to learners in smart learning environment,
there is need to incorporate CARS to pick learners
preferences and likes.
      </p>
      <p>
        Author [
        <xref ref-type="bibr" rid="ref24">24</xref>
        ], [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ], [
        <xref ref-type="bibr" rid="ref58">58</xref>
        ], and [
        <xref ref-type="bibr" rid="ref40">40</xref>
        ], all clarify that currently
learning activities have gone digital in most learning
institutions, with most of the learners preferring to use smart
learning platforms. Thus calling for the need to
automatically recommend to a learner certain activities at
any particular time of learning. This would in turn reduce the
time taken to manually searching for the relevant learning
activity. The recommended activities could range from
books for a certain level, courses to undertake, professionals
in a certain field etc.
      </p>
      <p>These activities are recommended based on the contexts
collected from a learner. Such that to recommend
professional to assist a learner, we may collect the location
details and level of expertise of a learner. Hence pointing out
that there are diverse contexts and context variables that can
be used in context aware systems. There are several research
that have been done in CARS in smart learning, with each
research addressing a particular research problem. In this
paper we surveyed existing literature in CARS for smart
learning that were in line with our research questions.</p>
    </sec>
    <sec id="sec-2">
      <title>II. BACKGROUND</title>
      <p>In our background we gave an insight of smart learning,
context aware recommender systems, environment and
techniques in smart learning. Context aware recommender
system components, how smart learning contexts are
collected from the environment and considerations when
designing smart learning context aware recommender
systems.</p>
      <sec id="sec-2-1">
        <title>A. Overview of smart learning</title>
        <p>
          Reference [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ], [
          <xref ref-type="bibr" rid="ref47">47</xref>
          ], [
          <xref ref-type="bibr" rid="ref22">22</xref>
          ], and [
          <xref ref-type="bibr" rid="ref42">42</xref>
          ], all point out that
smart learning is student concentric strategy mode of
learning in provision of learning materials, where a learner
will have diverse choices of learning at his fingertip, and
learning can be achieved at home, field, school, etc. All these
depends on the learner’s choice of learning.
        </p>
        <p>
          Author [
          <xref ref-type="bibr" rid="ref37">37</xref>
          ], [
          <xref ref-type="bibr" rid="ref52">52</xref>
          ], and [
          <xref ref-type="bibr" rid="ref8">8</xref>
          ], explain that a smart learning
system should be able to learn the users’ preferences based
on the environment of the learner. This is due to learners’
ever changing demands, hence it is imperative to keep
collecting the learner’s choice of preferences every time. The
collected learner preferences, can then be automated based
on the way that data was collected and the expected results.
        </p>
        <p>
          Source [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ], [
          <xref ref-type="bibr" rid="ref27">27</xref>
          ], [
          <xref ref-type="bibr" rid="ref44">44</xref>
          ], and [
          <xref ref-type="bibr" rid="ref57">57</xref>
          ], suggest that technology
enabled smart learning process usually takes the following
salient steps.
        </p>
      </sec>
      <sec id="sec-2-2">
        <title>1) Sensing</title>
        <p>It entails scanning the user and his environment then
collecting/sensing his particular requirements.</p>
      </sec>
      <sec id="sec-2-3">
        <title>2) Reasoning</title>
        <p>An array of artificial intelligence tools that analyze the
collected data using the sensors</p>
      </sec>
      <sec id="sec-2-4">
        <title>3) Acting</title>
        <p>It evolves around reacting to the environment, based on
the solutions offered by the reasoning stage</p>
      </sec>
      <sec id="sec-2-5">
        <title>B. Context aware recommender system environment and techniques components,</title>
        <p>
          Papers [
          <xref ref-type="bibr" rid="ref34">34</xref>
          ], [
          <xref ref-type="bibr" rid="ref22">22</xref>
          ], [
          <xref ref-type="bibr" rid="ref17">17</xref>
          ], and [
          <xref ref-type="bibr" rid="ref5">5</xref>
          ], all show that models of
context awareness systems starts by first sensing their
environment or contexts. During the sensing, they will
collect the contexts that they are adapted to collect. They
will then use their artificial intelligence to give an output, or
adapt to the environment in a manner that is proportional to
the collected contexts. Thus different contexts collected will
necessitate the context aware model to behave in a particular
fashion. Likewise [
          <xref ref-type="bibr" rid="ref26">26</xref>
          ], [
          <xref ref-type="bibr" rid="ref49">49</xref>
          ], and [
          <xref ref-type="bibr" rid="ref3">3</xref>
          ], suggest that there are a
number of environment awareness that context awareness
systems could perceive. These context aware environments
could be grouped as:
        </p>
      </sec>
      <sec id="sec-2-6">
        <title>1) Physical environment context</title>
        <p>This is where the context awareness data is one that is
related to physical world parameters. Such as location of
user, body temperature of user etc.</p>
      </sec>
      <sec id="sec-2-7">
        <title>2) Human environment context (user context)</title>
        <p>These contexts are pertaining to the user; such as: -User's
identity, habits of the user, to-do-list of the user etc.</p>
      </sec>
      <sec id="sec-2-8">
        <title>3) ICT context or virtual environment context.</title>
        <p>This is where the context awareness data is data relating
to a device in the distributed system. Such as GPS
location etc.</p>
        <p>
          Reference [
          <xref ref-type="bibr" rid="ref60">60</xref>
          ], [
          <xref ref-type="bibr" rid="ref33">33</xref>
          ], [
          <xref ref-type="bibr" rid="ref12">12</xref>
          ], research suggest that there are
several recommendation techniques that have been proposed
and used by a number of research. These recommendation
techniques include group-based, knowledge-based,
contentbased, demographic-based, utility-based, context-aware,
trust-aware, collaborative filtering, social network-based,
and hybrid technique. The choice of a technique depends on
the way contexts are to be collected and processed.
        </p>
        <p>Such that for group based recommendation, the
recommendation made are similar for members of a
particular group, while knowledge based will differ
depending on learner’s knowledge level. Demographic
based recommendation will focus on some demographics,
say how many times you have rated a certain item. While
hybrid recommendation, combines more than one
recommendation technique.</p>
      </sec>
      <sec id="sec-2-9">
        <title>C. How smart learning contexts are collected from the environment</title>
        <p>
          Papers [
          <xref ref-type="bibr" rid="ref23">23</xref>
          ], [
          <xref ref-type="bibr" rid="ref41">41</xref>
          ], [
          <xref ref-type="bibr" rid="ref33">33</xref>
          ], and [
          <xref ref-type="bibr" rid="ref39">39</xref>
          ], all point out that there are
several ways that have been put across to collect contexts for
learning systems. The collection depends on the
environment and type of context to be collected. These
contexts can be collected through: - Wi-Fi networks, RFID
(Radio frequency identification), wireless sensor networks
(WSNs), internet, mobile agents, mobile and wearable
sensors, and computer systems.
        </p>
      </sec>
      <sec id="sec-2-10">
        <title>D. Considerations when designing smart learning context aware recommender models</title>
        <p>
          Reference [
          <xref ref-type="bibr" rid="ref28">28</xref>
          ], [
          <xref ref-type="bibr" rid="ref50">50</xref>
          ], [
          <xref ref-type="bibr" rid="ref51">51</xref>
          ], [
          <xref ref-type="bibr" rid="ref16">16</xref>
          ], and [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ], all point out that
when designing smart learning context aware recommender
system, then the following factors are vital to consider for a
more comprehensive and user-friendly recommender
system. These considerations are diversity of
recommendations, recommender persistence, user privacy,
user demographics, recommendations serendipity, and trust.
        </p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>III. LITERATURE REVIEW</title>
      <p>Due to the evolution of MOOC (Multiple Open Online
Courses) available in the internet, with each course having
its own objective. There exist several CARS in smart
learning systems, each addressing a pertinent goal, justifying
the complexity and the several activities that can be
recommended in smart learning. Hence we restricted our
survey to CARS papers that addressed the following research
questions in pedagogical smart learning:




</p>
    </sec>
    <sec id="sec-4">
      <title>Which contexts are used in smart learning,</title>
      <p>How are the contexts collected,
What data mining and recommendation
techniques used to processes the contexts,
What are the recommended activities,</p>
      <p>Future work in CARS.</p>
      <p>During our literature search we identified several
articles on context aware recommender systems in learning.</p>
      <sec id="sec-4-1">
        <title>A. Selection of articles for review</title>
        <p>
          As outlined by [
          <xref ref-type="bibr" rid="ref4">4</xref>
          ], and [
          <xref ref-type="bibr" rid="ref45">45</xref>
          ], there are several research that
have been carried out in CARS smart learning; with each
recommending an activity and addressing their own gap.
        </p>
        <p>We searched through various journals, and conference
proceedings using the following terminologies:


</p>
        <p>Context aware recommender systems in learning,
Recommender systems in smart learning</p>
        <p>Context aware in education</p>
        <p>Several journal articles and conference proceedings were
availed. We selected journals published within this decade
and specifically addressing majority of our research
questions.</p>
      </sec>
      <sec id="sec-4-2">
        <title>B. Surveyed papers on context aware recommender systems for smart learning</title>
        <p>Below are some of the papers that we reviewed in smart
learning contexts aware recommender systems. Where we
had more than one author with similar research but different
findings, we documented all their findings under one title.</p>
      </sec>
      <sec id="sec-4-3">
        <title>1) Context-Aware Recommender Systems for E-Learning:</title>
      </sec>
      <sec id="sec-4-4">
        <title>A Survey and Future Challenges</title>
        <p>
          Author [
          <xref ref-type="bibr" rid="ref15">15</xref>
          ], [
          <xref ref-type="bibr" rid="ref32">32</xref>
          ], and [
          <xref ref-type="bibr" rid="ref53">53</xref>
          ], all argue that several research
have been conducted, on technology enabled learning
recommender systems. Majority of the studied models use
knowledge-based filtering, collaborative filtering and
hybrid techniques. These techniques depend on
recommendations that are to be suggested to a learner.
There are diverse contexts that are usable in smart learning.
These contexts are categorized as physical condition
contexts, computing contexts, user contexts, resources
contexts, time contexts, situation contexts etc.
        </p>
        <p>Several activities were recommended with these
recommender systems. These recommender systems were
to suggest any of the following activities:- teachers, peers,
learning content, knowledge levels, training needs, books,
institutions, lighting levels, learning styles, courses to
undertake etc.</p>
        <p>Their research identified some challenges and future
work, which include: - combining more than one context
groups to have a hybrid, contexts that have not yet been
used, automatic capturing of learners’ contexts, user
interests, and standard dataset for smart learning
recommendations. They also suggested other data mining
methods other than the mostly used nearest neighbour,
crowdsorcing, pattern matching and association rules.</p>
      </sec>
      <sec id="sec-4-5">
        <title>2) Automatic learner needs identification using context awareness and artificial intelligence</title>
        <p>
          Reference [
          <xref ref-type="bibr" rid="ref9">9</xref>
          ], [
          <xref ref-type="bibr" rid="ref29">29</xref>
          ] and [
          <xref ref-type="bibr" rid="ref56">56</xref>
          ] explain that context awareness
could be used to investigate learners’ behavior pattern and
offer them relevant solutions with regard to their learning
behavior. Their systems uses artificial intelligence and
context awareness to provide learners with their specific
likes. These likes, depends on their past data and the data
collected from their ubiquitous devices. However, these
systems are limited to recommending to a learner, the
reading content based on their previous likes unfortunately
their systems do not support dynamic learner preferences.
        </p>
      </sec>
      <sec id="sec-4-6">
        <title>3) Ubiquitous computing technologies and context aware recommender systems for ubiquitous learning</title>
        <p>
          Papers [
          <xref ref-type="bibr" rid="ref35">35</xref>
          ], and [
          <xref ref-type="bibr" rid="ref46">46</xref>
          ], Developed ubiquitous learning
system. The system integrates context aware and ubiquitous
computing technologies. Their system, a 2D or a QR bar
code that enabled students in getting recommendations on
the best herb that can be used for a particular ailment. The
various plants have an attached QR code, from which the
students can scan the plants QR code with their mobile
devices to identify the herb and to an extent the medicinal
values of the herbs. They used clustering algorithm and
association rules to unearth relationships in databases.
Collaborative filtering approach assists the algorithm to
identify the relationships.
        </p>
      </sec>
      <sec id="sec-4-7">
        <title>4) Keywords Learning Materials Recommendation</title>
      </sec>
      <sec id="sec-4-8">
        <title>Framework</title>
        <p>
          Reference [
          <xref ref-type="bibr" rid="ref21">21</xref>
          ], and [
          <xref ref-type="bibr" rid="ref59">59</xref>
          ], explain that there are a number of
E-learning material recommendation frameworks. In their
framework an instructor uploads learning content in the
database. Each content was given a keyword which will be
used for recommendation purposes. The keyword will have
content attributes such as title, author etc. A student will be
given recommendations based on the keyword that the
student has requested. There was a learner’s ratings for
these keywords. Further recommendations are given based
on average learner ratings of these keywords. Otherwise,
the recommender system will predict a good learners’
ratings for the item.
        </p>
      </sec>
      <sec id="sec-4-9">
        <title>5) Book Recommender System using Fuzzy Linguistic</title>
      </sec>
      <sec id="sec-4-10">
        <title>Quantifier and Opinion mining</title>
        <p>
          Author [
          <xref ref-type="bibr" rid="ref2">2</xref>
          ], [
          <xref ref-type="bibr" rid="ref14">14</xref>
          ], and [
          <xref ref-type="bibr" rid="ref57">57</xref>
          ], proposed a book recommender
system where learners give opinion and rate books, thus a
customer review for the available books. The customer will
give their opinion review online. The reviews will be
aggregated, and an ordered weighted average (OWA) will
be determined. A book with the highest OWA is usually
the one with the highest recommendation. This context
aware recommender suggests a number of books, and let a
user rate the books. It then recommends books with similar
OWA ratings as those that the learner rated highly in his
ratings. This is not practical where there are several books.
        </p>
      </sec>
      <sec id="sec-4-11">
        <title>6) Fuzzy Logic Based Context Aware Recommender for</title>
      </sec>
      <sec id="sec-4-12">
        <title>Smart E -learning Content Delivery</title>
        <p>
          Reference [
          <xref ref-type="bibr" rid="ref22">22</xref>
          ], and [
          <xref ref-type="bibr" rid="ref39">39</xref>
          ], suggest that Fuzzy logic-based
context aware recommender for smart E-learning content
recommender, is a model that collect learner’s context and
give suggestions of relevant learning material to a learner.
A learner will be provided with an assessment test. The time
taken to complete the test and the assessment test score, will
form the learner’s contexts.
        </p>
        <p>The collected contexts will be analyzed using type 1 fuzzy
logic, to output a learner’s knowledge level. The output
knowledge level from the fuzzy logic will be assigned to a
learner, which will then be used to recommend relevant
learning content for the learner. There will be a database
with learning contents OWA scored with the professionals
of that learning subject. Thus learning content with OWA
of + 10 from a learner’s knowledge level will be
recommended to the learner.</p>
      </sec>
      <sec id="sec-4-13">
        <title>7) Dynamic context aware learning objects in e-learning environment</title>
        <p>
          Reference [
          <xref ref-type="bibr" rid="ref38">38</xref>
          ], [
          <xref ref-type="bibr" rid="ref2">2</xref>
          ], and [
          <xref ref-type="bibr" rid="ref43">43</xref>
          ], elaborate that in context
aware E-learning environment, we could have either a
random user or an adequate user of E-learning system. We
have three modules that support the interpretation of user
contexts for all the users. These are the system contexts,
user contexts, and environment contexts.
        </p>
        <p>The existing context aware systems for E-Learning have
no standardized set of context parameters, hence the
selection of contexts is based on randomly considered set
of parameters. Some of the context parameters include:
Learner’s personal profile, level of expertise, preferences,
intention, quality of learning service, learner’s devices,
pace, state etc. That are used for recommendations.</p>
        <p>They suggest that there is need to have a standard model
incorporating all the three modules, in order to integrate all
the eLearning learning objects to achieve dynamic contexts.</p>
      </sec>
      <sec id="sec-4-14">
        <title>8) SMS based E-Assessments enabling better Student</title>
      </sec>
      <sec id="sec-4-15">
        <title>Engagement, Evaluation and Recommendation Services in</title>
      </sec>
      <sec id="sec-4-16">
        <title>E-Learning using Fuzzy Rules and Course Ontologies</title>
        <p>
          Author [
          <xref ref-type="bibr" rid="ref6">6</xref>
          ], and [
          <xref ref-type="bibr" rid="ref36">36</xref>
          ], research proposed models where
students interact with teachers as usual in class or using
elearning platforms. The models suggest that students will
answer quizzes pertaining to their interactions with the
teacher. The way a student answers the quizzes will now
guide the student on whether to proceed or revisit the earlier
topics. The model mines a student SMS response on a fuzzy
logic, which then gives the student personal
recommendation whether to proceed to the next topic or
not. The research is limited to course topics, and whether
the student is competent to proceed to the next topic based
on the SMS E-assessment score.
        </p>
      </sec>
      <sec id="sec-4-17">
        <title>9) E-learning group recommender systems: Combining</title>
      </sec>
      <sec id="sec-4-18">
        <title>User-User and Item-Item Collaborative Filtering</title>
      </sec>
      <sec id="sec-4-19">
        <title>Techniques</title>
        <p>
          References [
          <xref ref-type="bibr" rid="ref48">48</xref>
          ], [
          <xref ref-type="bibr" rid="ref1">1</xref>
          ], and [
          <xref ref-type="bibr" rid="ref11">11</xref>
          ], proposed that a group
recommender system has combined a hybrid of item-item
and user-user collaborative filtering techniques to build
their recommender systems. Implying that instead of
recommending based on similar users only, they also
incorporate both similar users and similar items in their
group collaborative filtering recommendations. They
further argue that majority of recommender systems were
group recommenders and not personal recommenders.
Noting that it would be difficult to build personal
recommenders for each user. Their have not built context
aware recommender system for every individual, but have
built a recommender system that consider the preferences
of a group of users and recommend to a user with reference
to a group that a user best fits.
10) Enhanced Recommendations for e-Learning Authoring
        </p>
      </sec>
      <sec id="sec-4-20">
        <title>Tools based on a Proactive Context-aware Recommender</title>
        <p>
          Author [
          <xref ref-type="bibr" rid="ref19">19</xref>
          ], [
          <xref ref-type="bibr" rid="ref20">20</xref>
          ], and [
          <xref ref-type="bibr" rid="ref30">30</xref>
          ] suggest that authoring tools are
powerful systems in the area of e-Learning. They assist
teachers to create new learning objects by reusing or editing
existing educational resources that are stored in learning
repositories. However, due to large number of resources
these tools access, it is usually difficult for teachers to find
the most suitable resources for their target level.
        </p>
        <p>
          The papers propose models that could generate proactive
context-aware recommendations on resources during the
creation process of new learning objects. The models use
context topics of the learning object and the target audience.
The models would then suggest suitable resources without
explicit user request being needed. Therefore, the user
would discover the resources during the creation process.
11) A Fuzzy Approach to Multidimensional Context Aware
e-Learning Recommender System (CA-ELRS)
Reference [
          <xref ref-type="bibr" rid="ref18">18</xref>
          ], and [
          <xref ref-type="bibr" rid="ref55">55</xref>
          ], point out that majority of the
learners context include: - mood, emotion, duration of
study, place, time, and social interaction. The paper thereby
works towards developing an effective multidimensional
CA-ELRS using mood and time duration as fuzzy logic
input concepts. Then through use of fuzzy logic, the crisp
output can be given, which will then be used to match the
relevant learning content.
12) Context-aware recommender for mobile learners
Author [
          <xref ref-type="bibr" rid="ref10">10</xref>
          ], and [
          <xref ref-type="bibr" rid="ref54">54</xref>
          ], research entail building mobile
recommender systems with semantic-rich awareness
information. Their content recommendations are tailored to
a learner’s background, context, and task at hand of the
mobile learner. These content recommendations are also
integrated with different operational characteristics such as
varying network bandwidth and limited mobile devices
resources. In incorporating all the above factors in one way
or the other, it was therefore necessary to consider a
proactive context awareness mechanism that can sense both
system-centric and learner-centric context and adapt the
accessed services on the go. The models use shared
ontology space and unified reasoning mechanism.
13) Constructing a User-Friendly and Smart Ubiquitous
        </p>
      </sec>
      <sec id="sec-4-21">
        <title>Personalized Learning Environment by Using a Context</title>
      </sec>
      <sec id="sec-4-22">
        <title>Aware Mechanism</title>
        <p>
          Author [
          <xref ref-type="bibr" rid="ref31">31</xref>
          ] and [
          <xref ref-type="bibr" rid="ref7">7</xref>
          ] developed intelligent personalized
context-aware recommendation learning systems. The
systems comprised of multimedia streaming learning
subsystem, and context-aware learning subsystem. The
learning content being recommended change with the
learner’s location and environment change. They provided
dynamically adjusted learning that is location-based. The
study used broadly defined term personalized mobile
learning due to various sensor technologies that is usually
incorporated in mobile equipment. These recommendations
were personalized learning, that change according to the
learner’s environmental information such as history,
regional traits, nearby buildings etc.
        </p>
      </sec>
    </sec>
    <sec id="sec-5">
      <title>RESULTS AND DISCUSSIONS</title>
      <sec id="sec-5-1">
        <title>A. Results</title>
        <p>From the above literature review, we managed to tabulate
the result in table 1 below for easy visualization and quick
follow-up, based on each CARS studied in smart learning.</p>
        <p>ACTIVITIES AND FUTURE RECOMMENDATIONS USED IN THE DEVELOPMENT OF SMART LEARNING CARS
-Learner moods
(happy, sad,
moody, etc.)
-Mobile learner
surrounding
contexts (GPS,
wireless nets,
security, etc.)
-GPS location
-QR code
- Mobile device
- Camera
- Computer
- GPS
- Computer
- Google maps
- Smart phone
- Barcode
- GPS
- Computer
- - Wi-Fi
- Wearable
sensors</p>
        <p>Multidimensional
Context Aware
eLearning
Recommender
Context-aware
recommender for
mobile learners
-Personalized
context-aware
recommendation
(PCAR) learning
system
- Item based
collaborative
filtering
- Ontology
reasoning
-Intelligent
personalized
context-aware
learning algorithm
- Aggregations of
contexts
- Suggest learning
content with regard
to learners moods
-Recommend
learning content to
mobile learners,
depending on mobile
surrounding context
-Location based
Mlearning, for
recommending
learning content
based on location
- Incorporation of
several moods and
emotions contexts
- Efficient context
integration and
adaptation
- Sufficient context
change adaptation
- Dynamic location
changes
- Mapping several
locations.</p>
      </sec>
      <sec id="sec-5-2">
        <title>B. Discussions</title>
        <p>
          As explained by Author [
          <xref ref-type="bibr" rid="ref18">18</xref>
          ], [
          <xref ref-type="bibr" rid="ref40">40</xref>
          ], [
          <xref ref-type="bibr" rid="ref54">54</xref>
          ], [
          <xref ref-type="bibr" rid="ref46">46</xref>
          ], and [
          <xref ref-type="bibr" rid="ref55">55</xref>
          ], as
well as from the results in table 1 of our study. We identified
that smart learning incorporates e-learning, mobile learning,
pervasive learning as well as ubiquitous learning. Each of the
above learning has its own set of tools and architectures. With
the evolution of MOOC and the various learning styles and
learner preferences. There exists several contexts that can be
used in designing context aware recommender systems,
depending on the contexts that can be collected, as well as the
learning architecture to be developed.
        </p>
        <p>These learning contexts can be grouped as user context
(preference, intention, moods, knowledge level, expertise,
frequency, goals, keywords, language, background etc.).
Environment context (GPS location, region, temperature,
time, proximity, day etc.), or System context (hardware,
software, network, system speed, etc.).</p>
        <p>Due to the various contexts in CARS in smart learning,
there are diverse strategies of collecting user contexts in smart
learning. These strategies depend mainly on the CARS
architecture and environment from which the contexts are to
be collected. Such collection methods include: - the use of
computers, Wi-Fi, wearable sensors, QR code, internet,
RFID, touch screens, etc. User contexts tends to use majorly
wearable devices and computers. Environment contexts tend
to use gadgets that can collect environmental contexts, such
as GPS, Wi-Fi, thermometers etc. As system contexts tend to
use computers, timers, internet etc.</p>
        <p>We also noted that there are various recommendation and
data mining techniques, which extracts useful information
from learner contexts and guide the recommendation
intelligence. These recommendation techniques used include
content-based, group-based, knowledge-based,
demographicbased, utility-based, trust-aware based, social network-based,
fuzzy-based, collaborative filtering, and hybrid
recommendation. On the other hand, the data mining
techniques that can be used in mining learning content in
smart learning include: - nearest neighbour, regression,
crowdsorcing, pattern matching, association rules, clustering
algorithm, normal search, ordered weighted average and
collaborative filtering.</p>
        <p>Our results in table 1 further indicate that each and every
context aware recommender system in learning is addressing
a particular goal, thus diverse future work with regard to their
individual goals. Some of the items that have been
recommended in smart learning include: - recommendations
of learning material, teachers, peers, topics, learning content,
lighting styles, levels of learning, etc. In our survey, we noted
that there exist several recommender systems that recommend
similar activities, say learning content; but with different
contexts collected from a learner. This then confirms that, we
do not need to collect same contexts for similar
recommendations.</p>
        <p>Similarly, same contexts could be collected from learners
using different CARS, but lead to different activities being
recommended to a learner. For example, in order to
recommend relevant books to a particular learner, any or a
combination of the following contexts can be collected from
learners: - learner preference, keywords, level of study,
expertise, etc. The contexts collected depend entirely on the
architecture, data mining method, user profiles, context
variables, and strategies for collecting learners’ contexts.</p>
        <p>There are still several areas of research that have not been
fully exhausted regarding CARS in smart learning, especially
with the evolution of MOOC and learner centric learning. For
example, in a research to recommend relevant books to a
learner, when one has picked similar contexts. Then the
following could be issues of concern.</p>
        <p>Taking: Strategies for collecting learners’ contexts …….…….A
 Recommendation techniques and data mining techniques
used in CARS ……………..…………….……..……. B
If there are 7 strategies through which specific learner
contexts can be collected, and 6 data mining techniques that
can be used for the research. So A=7, and C=6. Then this
research alone would have 7x6 = 42 possibilities. If we decide
to diversify the contexts, then even more possibilities will be
available exponentially for the same research.</p>
        <p>Following the fact that there are several parameters to be
addressed in CARS in smart learning, then there arises several
possibilities, challenges, and future work.</p>
      </sec>
    </sec>
    <sec id="sec-6">
      <title>V. CONCLUSION AND RECOMMENDATIONS</title>
      <sec id="sec-6-1">
        <title>A. Conclusion</title>
        <p>This survey justifies that there are several context aware
recommender systems in smart learning, with several areas
that have not been fully researched. This can be attributed
by the several learner contexts available; various
recommendation and data mining techniques, various
strategies through which contexts can be collected, and the
numerous activities that can be suggested in smart learning.</p>
        <p>This study further points out that due to the evolution of
MOOC and learner centric learning, the aspect of CARS in
offering smart learning is even being complicated with
technological advancements. These are due to the random
set of parameters, several existing context variables that a
CARS can choose, and diverse learner preferences. Hence
there is no set standard for building CARS in smart
learning, but open to individual researcher.</p>
        <p>The survey further illustrate that there exist numerous
contexts, context variables, data mining techniques,
strategies for collecting contexts and CARS for smart
learning. But despite the various context aware
recommender systems in place, there is no recommender
system that fully fits every learner’s preference. This is due
to the ever changing learner preferences, contexts and
learning environments.</p>
      </sec>
      <sec id="sec-6-2">
        <title>B. Recommendations and future work</title>
        <p>There exists different CARS research in smart learning as
indicated in table 1, although each context aware
recommender system is addressing a specific goal. Even
though the CARS could have same goals, they would have
utilized different set of contexts, diverse recommendation
techniques, or different strategies through which contexts are
collected.</p>
        <p>Due to the dynamic and ever changing learners’
preferences and contexts, the following gaps arise:
 Automatic extraction of learner contexts especially for
big databases without cold start problems,




</p>
        <p>Capturing ever changing learners’ contexts in real time,
Development of a situation aware CARS that can be
able to perceive every context situation (i.e. if the
environment is noisy / unconducive for learning hence
postpone learning),
Mapping of several locations in context aware data,
Sharing of recommendations or contextual information
over big data databases,</p>
        <p>Standard context capturing devices in smart learning,
 Developing a proactive CARS other than the traditional
user requests and response given scenarios.</p>
        <p>From the above gaps, we recommend building of a smart
learning CARS that would be able to have a universal
framework / model and platform for smart learning, with a
standard database for contextual data and recommended data
for every learner in smart learning.</p>
      </sec>
    </sec>
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