Towards Ubiquitous Learning Situations for Disabled Learners
Nesrine Ben Salah
a
, Ines Bayoudh Saadi
b
and Henda Ben Ghezala
c
National School of Computer Science, Manouba University, RIADI Research Laboratory, Tunis, Tunisia
Keywords: Ubiquitous Learning, Disabled Learners, Learning Situation, Learning Process, Situation Identification,
Ontology Representation.
Abstract: Adaptation in ubiquitous learning environment is a major concern in research work, especially for disabled
learners. A number of studies have examined context-aware learning systems, but the learning situation has
rarely been taken into account, and mainly for learners with disabilities. There is a lack of studies on the
description and identification of learning situations for disabled learners. Therefore, these situations need to
be well defined, to ensure that all features, including the guidance of the learning process, are properly adapted
to this particular type of learners. The identified situation is linked to a situation model called a typical
situation. In this paper, we propose an ontology for ubiquitous typical learning situations relating to disabled
learners and more specifically, to those with sensory disabilities. We will then be able to refer to these
situations in order to identify the observed learning situations during the execution of the learning process.
This identification will then be used to recommend and guide the learning process of learners with disabilities.
1 INTRODUCTION
In recent years, the Situation Awareness (SA) has
become a critical success factor for adaptive systems
(DAniello and al., 2014). As technology evolves,
many complex and dynamic systems have been
created, affecting the ability of humans to act as
effective and timely decision-makers to exploit these
systems (Endsley, 2017). The learner's situation
awareness will be presented as a crucial construct
upon which decision-making and performance in
such systems lie.
In a situation-aware ubiquitous learning
environment, everything is adapted according to the
learning situation of the learner. And when it comes
to a disabled learner, this adaptation also takes into
consideration his type of disability. However,
disabled learners may have a different learning
context or experience a given learning context
differently from non-disabled learners (Salah, N. B.
and al., 2019). For instance, accessibility features are
particularly important for disabled learners. This
gives rise to the need to describe and identify a
specific learning situation for them.
a
https://orcid.org/0000-0001-7217-5676
b
https://orcid.org/0000-0001-7419-3800
c
https://orcid.org/0000-0002-6874-1388
Several learning situations have been proposed in
the literature. However, these situations are specific
to non-disabled learners, as the case of learning
situations proposed by Gwo-Jen Hwang in (Hwang,
2006). The situation awareness has been used to
promote adaptation. We can cite the work described
in (Saâdi and Hamdani, 2019) where authors
proposed recommendations using ubiquitous learning
situations. We also mention the work of DAniello
(DAniello and al., 2015) in which authors proposes a
prototypical Decision Support System supporting
learners in self-regulating their learning processes
based on Situation Awareness approach. Finally, in
(Souabni, R. and al., 2019), authors propose a
multidimensional framework dedicated for situation-
aware u-learning systems. It helps to understand,
analyse and describe in-depth a particular aspect of
situation awareness in u-learning systems
There is a lack of description of ubiquitous
learning situations for disabled learners. This
description is essential for adapting learning systems
to disabled learners according to their learning
situation.
144
Ben Salah, N., Saadi, I. and Ben Ghezala, H.
Towards Ubiquitous Learning Situations for Disabled Learners.
DOI: 10.5220/0009829201440151
In Proceedings of the 15th International Conference on Software Technologies (ICSOFT 2020), pages 144-151
ISBN: 978-989-758-443-5
Copyright
c
2020 by SCITEPRESS Science and Technology Publications, Lda. All rights reserved
In this paper, we will propose an ontology to
describe ubiquitous learning situations related to
disabled learners and more specifically to those with
sensory disabilities (visual or auditory). The main
contribution of this paper is the proposal of new
ubiquitous learning situations ontology for disabled
learners.
The rest of the paper is organized as follow.
Section 2 presents the conceptual background. The
proposal of ubiquitous learning situation for disabled
learner is given in Section 3 while Section 4
demonstrates an illustrative example through a
typical case study. Finally, conclusions are presented
in section 5. They review the main results and discuss
future works.
2 CONCEPTUAL BACKGROUND
2.1 Ubiquitous Learning Systems
Several ubiquitous learning systems have been
proposed in the literature. These systems support
users in their learning and teaching activities using
embedded and networked computing technologies,
sensors and actuators. (Souabni and al., 2016)
Context is a key element of an architecture based
on ubiquitous computing, because it is at the center of
the adaptation mechanisms advocated by the so-
called context-sensitive systems. These systems are
characterized by their capacity to adapt their
operation in order to increase their usability and
efficiency by taking into account the surrounding
context.
However, it is more convenient for ubiquitous
learning systems to treat more significant data than
low-level sensor ones. They must understand the
meaning of what they perceive. It may be useful to
interpret detected low-level context pieces or to
combine low-level and/or interpreted ones to get
more abstract and relevant context. Subsequently, it
is of great importance for context-aware learning
systems to proceed with a high abstraction of detected
context information pieces which is known as the
situation identification.
2.2 Situation and Situation Awareness
Recent attention to the learning situation was made
by Pernas in (Pernas and al., 2014) in order to
promote the detection of a rich learning situation and
to provide a conscious learning of the situation.
The situation awareness process was widely
defined in cognitive studies; the most referred
definition, even in computer system field, is stated by
Endsley as “the perception of the elements in the
environment within a volume of time and space, the
comprehension of their meaning, and the projection
of their status in the near future” (Endsley, 2000).
In human factor studies, the most referenced and
recognized situation awareness process model is the
one proposed by Endsley (Endsley, 2017). As stated
by authors in (Kokar and al., 2009), Endsley's
cognitive situation awareness process was used as a
justification for the definition of the situation
awareness process performed by the system.
The detection and the inference (interpretation
and/or aggregation) are main steps of the situation
awareness process. This process is able to abstract the
current state of user's situation (Souabni and al.,
2018).
2.3 Disabled Learners
A medical model approach to disability is still very
common. This considers the disadvantages
experienced by disability people to be the result of
their disabilities and focuses on individual solutions
of trying to overcome these disabilities and making
the disabled person more like a non-disabled one.
However, organisations of disabled people prefer a
social model approach which focused on the barriers
they experience, including as a result of both negative
attitudes and the mismatch between their needs and
the design of services, products and systems. (WHO,
1980)
A given learning environment may include
several types of learners, including both disabled and
non-disabled learners. We distinguish between
learner with different and specific needs (disabled and
non-disabled learners). Disability is still most
commonly considered from a medical model
perspective, leading to a deficit-based focus. This
then leads to categories based on the particular
impairment (WHO, 1980), such as physically
disabled, visually impaired, hearing impaired and
cognitively impaired.
In this paper, we are interested in sensory
handicaps (Kavcic, 2005): Visual impairments
(blindness, partial sight and color blindness): include
the range from low vision to full blindness, where the
user cannot use the visual display at all.
Hearing impairments (deafness and hearing loss):
have difficulties detecting sounds or distinguishing
auditory information from the background noise.
Deaf individuals cannot receive any auditory
information at all. Many of them communicate
through the Sign Language.
Towards Ubiquitous Learning Situations for Disabled Learners
145
Most learners with disabilities are able to employ
technical aids usually referred to as assistive
technology. Several assistive technologies are
available in the different learning systems (Voice
recognition programs, screen readers, etc.). However,
the need is different when it comes to a situation-
aware ubiquitous learning system. Indeed, learners
are learning while moving and their context is also
changing.
In addition to the accessibility of the course
content, a disabled learner must be guided in his
learning process. Since this is not a face-to-face
learning and since it is without the presence of a
teacher, the learner is generally not accompanied. It
is for this reason that the identification of the learning
situation is a fundamental step in ensuring a smooth
learning process.
3 PROPOSAL OF UBIQUITOUS
LEARNING SITUATION FOR
DISABLED LEARNERS
For learning a new concept, the system must detect
the context and analyze it in order to associate a
typical learning situation (from a pre-established list
of typical situations) with the contextual situation
observed. In what follows, we define the process to
follow in order to define the new learning situations
for disabled learners in ubiquitous learning
environment. The ubiquitous learning situation
definition process for disabled learners, as depicted in
Fig. 1, is a two-phase process and each phase contains
two steps.
Figure 1: Ubiquitous Learning situation definition process
for disabled learners.
3.1 Situation Description
A hierarchical approach that models the ubiquitous
learning context is described in (Salah, N. B. and al.,
2019). This approach presents an overview of an
ontology-based context model for situation-aware
ubiquitous learning systems. This context considers
learners with and without disabilities.
We briefly recall the ontology described in (Salah,
N. B and al., 2019) so that we can use it in the rest of
our process. Fig. 2 presents the hierarchy of the
classes of the proposed ontology as well as the data
property and object property.
3.1.1 Step A.1 Selection of Required Context
Element for Situation Description
Many valued context elements are used to infer a
situation however only some context information
values associated to some context elements are used
to describe a typical situation. In order to define
typical ubiquitous learning situations for disabled
learners, we consider the following contextual
elements, which are useful for the definition. Each
contextual element is described by values.
To facilitate this step, we consider in this paper
only one value of the two contextual information
"Learning preference" and "Facilitation preference"
which are "Real World Learning" and "Online
Guidance" respectively. The following table (Table
1) describes the contextual elements as well as the
values taken into account in our study for the
proposition of the typical learning situations.
We recall that the notion of "learner's peers" was
introduced by authors in (Hwang and al., 2008). This
notion has been detailed by the authors in (Souabni
and al., 2018) who describe peer helper as a person
who help the learner during his/her learning for a
given concept and the peer learners as learners who
cooperate with the learner to learn the same learning
concept.
Table 1: Required context elements.
Context Elements Values
Cooperation Level
Non-Cooperative
Communicative
Participative
With Initiative
Insightful
Useful
Disability Type
Hearing Impairment
Visual Impairment
Facilitation Preference Online Guidance
Learning Preference Real World Learning
Learning Style
Reflector
Pragmatist
Theorist
Peer Helper Boolean
Peer Learner Boolean
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Figure 2: A hierarchical view of the key ontology classes, object-properties and data-type properties.
3.1.2 Step A.2 Mapping between Context
Elements Values and Atomic
Situations
The current learning situation definition of the
disabled learner is done by referring to typical
learning situations. Each typical situation is
composed by a list of atomic situations. These latter
are described by values of contextual elements that
represent the identification criteria. The relationships
between these concepts are described in Fig. 3.
Figure 3: Relation between Typical Situation, Atomic
Situation and Context Elements.
Subsequently, we adopt the approach described in
(Hwang and al., 2011), in order to add new atomic
situations that are specific to disabled learners. For
example, if the context element “Cooperation level”
has the value “Insightful”, “Useful”, “With initiative”
or “Participative”, and the learner is in an
environment where there are Peer helper and / or Peer
Learner, we can say that we are in the learning atomic
situation “Cooperative learning”.
We also take the example of a learner who has a
visual impairment. The type of visual impairment is
“Blindness”. The learners atomic learning situation
will then be “Learning with blindness disability”. The
atomic situations and their identification criteria are
listed in table 2.
Table 2: Identification criteria for atomic situations.
Identification
criteria
Identification Value Atomic
situations
Learning
preference
Real World
Learning in
the Real
world
Facilitation
preference
Online Guidance
Learning with
Online
guidance
Learning
Style
Type Nature
Hearing
Impairment
Hearing
Loss
Learning with
hearing loss
Disability
Deafness
Learning with
deafness
disability
Visual
Impairment
Partial
Sight
Learning with
partial sight
disability
Blindness
Learning with
blindness
disability
Cooperation
Level
Non cooperative
Individual
Learning
Insightful
Useful
With initiative
Participative
Cooperative
Learning
Peer Learner True
Peer Helper True
Towards Ubiquitous Learning Situations for Disabled Learners
147
3.2 Situation Definition
The definition of the learning situation is composed
of two steps. The first deals with the formulation of
atomic situation identification rules while the second
presents the definition of typical situation. Indeed, the
identification of the learning situation for learners
with disabilities is the ability to deduce the situation
from the aggregation of atomic situations already
identified.
3.2.1 Step B.1 Formulation of Atomic
Situation Identification Rules
In order to determine the situation that most
characterizes the disabled learner's current learning
situation, we propose the identification rules for the
atomic situations that will later compose the typical
learning situations.
Here are three examples of rules that describe the
following atomic situations: “Learning with hearing
loss Disability”, “Learning with partial sight
disability” and “Cooperative Learning”. These rules
are described in Fig. 4, 5 and 6.
Figure 4: Identification rule of the atomic situation
“Learning with hearing loss Disability”.
Figure 5: Identification rule of the atomic situation
“Learning with partial sight disability”.
Figure 6: Identification rule of the atomic situation
“Learning by problem solving”.
Taking the example of a learner with a hearing
impairment and to whom we have performed a test to
determine his hearing level. If the result of this test
gave that learner has a hearing level equal to “Mild
hearing loss” or “Moderate hearing loss” (represented
by the values “1” and “2” respectively in the ontology
described in (Salah, N. B. and al., 2019)), the learner
will be in the atomic situation “learning with hearing
loss disability”.
3.2.2 Step B.2 Definition of Typical
Situation
A typical situation is considered as a composite one
for which a list of atomic situations is attached. Based
on those atomic situations, we propose twelve typical
situations for disabled learner in a situation-aware
ubiquitous learning environment. The mapping
between atomic situations and typical situations is
given in Table 3.
Table 3: Atomic and typical situations.
Atomic Situations Typical situations
Cooperative Learning, learning
with deafness disability, learning
with online guidance, learning by
data collection, Learning in the
real world
ST
H
1=
Cooperative data
collection with
deafness disability
Individual Learning, Learning
with deafness disability, Learning
with online guidance, Learning in
the real world, Learning by object
identification
ST
H
2=
Identification of
real-world object
with deafness
disability
Individual learning, Learning with
deafness disability, Learning with
online guidance, Learning in the
real world, Learning by
experimentation, Learning by
problem solving
ST
H
3=
Problem solving
via
experimentation
with deafness
disability
Cooperative Learning, Learning
with hearing loss disability,
Learning with online guidance,
Learning by data collection,
Learning in the real world
ST
H
4=
Cooperative data
collection with
hearing loss
disability
Individual Learning, Learning
with hearing loss disability,
Learning with online guidance,
Learning in the real world,
Learning by object identification
ST
H
5=
Identification of
real-world object
with hearing loss
disability
Individual learning, Learning with
hearing loss disability, Learning
with online guidance, Learning in
the real world, Learning by
experimentation, Learning by
problem solving
ST
H
6=
Problem solving
via
experimentation
with hearing loss
disability
Cooperative learning, Learning
with blindness disability, Learning
with online guidance, Learning by
data collection, Learning in the
real world
ST
H
7=
Cooperative data
collection with
blindness
disability
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Table 3: Atomic and typical situations (cont.).
Atomic Situations Typical situations
Individual learning, Learning with
blindness disability, Learning with
online guidance, Learning in the
real world, Learning by object
identification
ST
H
8=
Identification of
real-world object
with blindness
disability
Individual learning, Learning with
blindness disability, Learning with
online guidance, Learning in the
real world, Learning by
experimentation, Learning by
problem solving
ST
H
9=
Problem solving
via
experimentation
with blindness
disability
Cooperative learning, Learning
with partial sight disability,
Learning with online guidance,
Learning by data collection,
Learning in the real world
ST
H
10=
Cooperative data
collection with
partial sight
disability
Individual learning, Learning with
partial sight disability, Learning
with online guidance, Learning in
the real world, Learning by object
identification
ST
H
11=
Identification of
real-world object
with partial sight
disability
Individual learning, Learning with
partial sight disability, Learning
with online guidance, Learning in
the real world, Learning by
experimentation, Learning by
problem solving
ST
H
12=
Problem solving
via
experimentation
with partial sight
disability
We consider the example described in Section 3
(Step A.2) where the atomic situation of the learner
was “Learning with blindness disability”. If in
addition, the system has detected through the value of
the detected contextual elements that this learner is
also in the following situations: “Individual learning”,
“Learning with online guidance”, “Learning in the
real world”, “Learning by experimentation” "and
“Learning by problem solving”.
According to the identified atomic situations, we
implement rules to define the learner’s learning
situation. OWL does not provide facilities to create
inferences about individuals. This is possible through
the combination of OWL with SWRL (W3C
Semantic Web Rule Language), since it allows the
definition of rules expressed in terms of OWL
concepts. Thus, SWRL was chosen to describe the
situation definition rules. It will then detect that the
typical learning situation of this learner is “STH9 =
Problem solving via experimentation with blindness
disability”. This rule and other rules examples are
descripted in Table 4.
4 ILLUSTRATIVE EXAMPLE
Let’s consider the learner “Learner 1” who has a
partial sight disability (Visual Impairment Class). He
prefers online guidance (Facilitation Preference
Class) to support learning. The learner like to
understand the theory behind the actions and need to
be able to see how to put the learning into practice in
the real world (Learning Style and Learning
preference Classes). He is learning on his own and did
not enjoys interaction (Cooperation level Class).
Table 4: Learning Situation Definition rules.
Learning
Situations
Rules definition
S
TH
9
(HasVisualAcuity (?a,3) HasVisualAcuity (?a,4) HasVisualAcuity (?a,5) HasVisualAcuity
(?a,6)) Has_Disability (?a,Visual_Impairment) HasLearningPreference(?a,RealWorllearning)
Has_Learning_Style (?a,Pragmatist) Has_Learning_Style (?a,Theorist)
(HasFacilitationPreference(?a, OnlineGuidance) Has_Situation(?a,
Problem_solving_via_experimentation_with_blindness_disability)
S
TH
1
Has_Disability (?a, HearingImpairment) ((HasHearingRank(?a,3) HasHearingRank(?a,4))
HasLearningPreference(?a,RealWorllearning) HasLearningStyle(?a,Reflector)
(HasFacilitationPreference(?a, OnlineGuidance) Has_Situation(?a,
CooperativeDataCollectionWithDeafnessDisability)
S
TH
2
Has_Disability (?a, HearingImpairment) ((HasHearingRank(?a,3) HasHearingRank(?a,4))
HasLearningPreference(?a,RealWorllearning) (HasFacilitationPreference(?a, OnlineGuidance)
Has_Learning_Style (?a,Reflector) Has_Situation(?a, Identification_of_real-
world_object_with_deafness_disability)
Towards Ubiquitous Learning Situations for Disabled Learners
149
In what follows, we will try to identify the typical
situation of this learner. Through the described
scenario, we can extract the identification criteria and
their values which are described in table 5.
Table 5: Values of the identification criteria.
Identification criteria Values
Disability = Visual Impairment Partial sight disability
Facilitation preference Online Guidance
Learning Style Pragmatic / Theorist
Learning Preference Real world learning
Cooperation Level Non-Cooperative
Some context information, are detected using
sensors. They come in part from the answers to
questionnaires or tests, such as the visual impairment
test. Generally, a Snellen chart is used for visual
acuity testing. The different values and levels of
visual acuity are described in (Salah, N. B. and al.,
2019).
During execution, identification rules are verified.
Based on the detected context in the described
scenario, the inference engine will execute the rules
that correspond to the mapping between the detected
contextual elements, their values and the
corresponding atomic situations (AS).
The different atomic situations identified in this
case are:
AS1: Learning with partial sight disability
AS2: Learning with Online guidance
AS3: Learning by problem solving
AS4: Learning in the Real world
AS5: Individual Learning
The application of the rules for defining learning
situations allows us to define the current learning
situation of this learner which is in this case, STH12
“Problem solving via experimentation with partial
sight disability” for the learner “Learner 1”. The
definition rule applied to define this situation is
described as follow:
Fig. 7 illustrates a simplified representation of the
typical learning situation definition process for this
illustrative example.
5 CONCLUSIONS
This paper presented an approach for proposing new
ubiquitous learning situations for disabled learners. A
brief review of the literature showed the lack of a
specific learning situation for the disabled learner.
This proposal was illustrated by a case study through
which we developed a reasoning that describes the
typical learning situation for a disabled learner given
according to the proposed identification rules.
The proposal of typical learning situations for
learners with disabilities will enable us to provide
accessible guidance for these learners, based on their
Figure 7: Illustrative Example.
HasVisualAcuity (?a,1) HasVisualAcuity
(?a,2)) Has_Disability (?a,Visual_Impairment)
HasLearningPreference(?a,RealWorllearning)
Has_Learning_Style (?a,Pragmatist)
Has_Learning_Style (?a,Theorist)
(HasFacilitationPreference(?a, OnlineGuidance)
Has_Situation(?a,
Problem_solving_via_experimentation_with_par
tialSi
g
ht
_
disabilit
y
)
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identified ubiquitous learning situation. With these
tips, we can recommend the most appropriate
learning strategy for the learner in a given ubiquitous
learning situation. Another future work that concerns
uncertainty in these ubiquitous environments, we will
then consider, to give a degree of confidence by
proposing a fuzzy ontology to describe the context
and ubiquitous learning situations. Large-scale
experimentation is feasible for future work.
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