A B-LEARNING APPROACH FOR ELECTRICAL
ENGINEERING BASED ON WIRELESS ACCESS TO
PEDAGOGICAL E-CONTENT
Pedro Assunção, Carla Lopes and Rafael F. S. Caldeirinha
Polytechnic Institute of Leiria / ESTG – Institute of Telecommunicatiosn,
Morro do Lena – Alto Vieiro 2401-911 Leiria, Portugal
Keywords: b-Learning, e-Content, Wireless Access, Electrical Engineering.
Abstract: This paper describes a novel pedagogical approach
and its application to undergraduate Electrical
Engineering courses. A b-learning model is proposed where students are subject to different types of
interactions and diverse learning experiences characterised by the type learning session and pedagogical
agent in use. These include face-to-face teaching sessions in the classroom, standalone e-learning sessions,
working groups and supervised laboratory work. A wireless LAN infrastructure, as part of the Portuguese
Electronic University Project, is used for the e-learning component of the proposed approach. In practice,
this is an application of the “anywhere, at anytime” concept to learning processes by extending classroom
boundaries in both space and availability domains. From a technical point a view, the paper addresses the
information network infrastructure used and its quality of service in multimedia communications, the e-
content generation, its characteristics, requirements and possible adaptation to heterogeneous environments.
A student survey was conducted to evaluate technical and pedagogical aspects of the learning process using
the proposed model. The results show this is a promising approach towards flexible learning in Higher
Education Institutions and also revealed that students tend to adapt rather slowly to emerging pedagogical
approaches, though they are truly in favour to use IT in their own learning processes.
1 INTRODUCTION
Nowadays, there is a fast growing use of information
technology (IT) in education where Higher
Education Institutions are, to a certain extent,
responsible for opening new frontiers by accepting
new challenges and foreseeing the future. In the last
decade, Higher Education in general has experienced
profound changes mainly driven by IT, which
includes not only the pedagogical processes, but also
management and administrative processes that
became totally dependent on computers, software
applications, databases, and communication
networks of all kind (Duderstadt, 2001). The
integration of IT in today’s undergraduate education
has appreciably modified the nature of student
interactions within their own learning processes. By
simple comparison, it is obvious to realise that the
heart of IT is comprised of similar components as
the pedagogical process roots: information and
communication. As a consequence of the continuous
evolution of information and communication
technologies, innovative learning-oriented
applications and pedagogic approaches have been
proposed (Castro et al., 2001).
Wireless communication technology is
un
doubtedly a field where fast technology advances
have been witnessed almost on a daily basis over the
last few years. However, only recently, wireless
technology has become cost effective and therefore
attractive to be used in education (Nyiri, 2002) (Tzu-
Chien et al., 2002) (Lehner et al., 2004).
In this paper, a blended learning (b-learning)
m
odel supported by wireless technology, is
proposed. This work is also a response to the new
challenges and opportunities created by the
Portuguese Electronic University Project (e-U),
which is a pioneering practical attempt to reshape
the Higher Education institutions in Portugal. The
wireless local area network (WLAN), as the core of
the virtual campus is a major component of the
supporting technology along with content generation
and storage equipment. Recently proposed
277
Assunção P., Lopes C. and F. S. Caldeirinha R. (2006).
A B-LEARNING APPROACH FOR ELECTRICAL ENGINEERING BASED ON WIRELESS ACCESS TO PEDAGOGICAL E-CONTENT.
In Proceedings of the International Conference on Signal Processing and Multimedia Applications, pages 277-286
DOI: 10.5220/0001573402770286
Copyright
c
SciTePress
approaches for content generation were taken into
account (Schutz et al., 2003) (Chen et al., 2003) and
a novel content adaptation method to deal with
heterogeneous mobile environments, is proposed.
The b-learning approach implemented in the
course of this work is built on top of an efficient
combination of technology, human resources and
other intangible assets such as knowledge and
interaction capabilities. It is demonstrated that such
a learning model is possible to be deployed and it is
useful from both the learner and academic institution
perspectives.
The paper is organised as follows. Section 2
provides a general description of the information
network infrastructure that supports the proposed
pedagogic model. Section 3 describes the most
important aspects of the multimedia content,
specifically produced in the course of this work and
used in e-learning sessions. Both technical and
pedagogical aspects are addressed. In section 4, the
proposed b-learning model for undergraduate
engineering courses is presented, while section 5
deals with the evaluation of the whole process
through a student survey that was carried out for the
purpose of this work. Finally, conclusions are drawn
in section 6.
2 INFORMATION NETWORK
INFRASTRUCTURE
2.1 General Overview
The information network is mainly used in the e-
learning sessions of the pedagogical process
described in section 4 and consists of four distinct
modules, i.e. Content Generation (CG), Content
Manager (CM), Fixed Content Access (FCA) and
Wireless Content Access (WCA), as shown in
Figure 1. The CG module is responsible for the
multimedia data acquisition and encoding processes
and is comprised of external acquisition devices (e.g.
video camera, microphone, VCR) connected to a
personal computer by means of an MPEG-2 real
time encoder board. The CM comprises of a specific
media management application and a multimedia
server. The encoded multimedia content is stored on
a multimedia server via a local area network (LAN).
The system is based on a client/server software
solution controlled by the CM through specific
instructions to other modules, which allows one to
deliver multimedia streaming of academic content,
either real-time encoded from live lectures or
produced off-line to (i.e. stored in the server) to
fixed and mobile terminals using a fixed or wireless
network, respectively. It supports several streaming
formats such as AVI, MPEG, QuickTime, etc.
Fast Ethernet (100Mbit/s)
Gigabit Ethernet
Laptop PC
The CM allows for scheduled services,
appropriate content management and load balancing
between different on-campus servers. The recorded
audio and visual streams may be delivered to end
users either in a scheduled mode, using IP
Multicasting, or on request, using Video on Demand
(VoD). The CM user interface was developed in
Java to allow remote access from any web browser
and enhanced security capabilities such as password
protection for access to dedicated applications and
encryption of multimedia content. Subsequently, the
FCA module allows fast Ethernet access (up to 100
Mbps) to multimedia content from ordinary desktop
PCs distributed among laboratories, classrooms and
offices. Due to the limited number of fixed desktop
PCs and their unavailability during daytime (e.g.
while classes are in progress), the system was
extended to provide additional access using fast
wireless local area networks (WLAN). The WCA
module is responsible to provide extended mobile
coverage to users using handheld or laptop
equipment. The wireless access requires the use of
specific hardware compatible with the 802.11
standard (Institute of Electrical and Electronic
Engineering ,1999), allowing transmission data rates
as high as 54Mbps, as described in the next
subsection.
The application used for viewing the encoded
multimedia content runs on any machine or mobile
terminal running on Windows operating system. The
CM provides this user application with detailed
information about all available e-content in the
multimedia server, listing them in a hierarchical
order to be viewed. The user may also select e-
Media Server
Desktop PC
Content Manager
AP
MPEG-2 Codec
Desktop PC
Audio & Video
Infrastructure
e-Content
Generation
Wireless Access
e-Content Access
Information and
Communication
E-Content
Laptop PC
AP
Fixed Access
Figure 1: Block diagram of the general communication
system.
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content on demand or even subscribe to other e-
contents to be viewed at a later time. The application
may be installed as a plug-in for any web browser
or, alternatively, it can run as an independent
application.
2.2 Wireless Content Access: Main
Features
A. IEEE 802.11 standard
The international standard on wireless local area
networks (WLAN) – IEEE802.11 (Institute of
Electrical and Electronic Engineering ,1999) refers
to the components of WLANs, which consist of a
wireless network interface card (often known as
station - STA), e.g. PCMCIA cards, and a wireless
bridge referred to as access point (AP). The AP
interfaces the wireless network with the wired
network (e.g. Ethernet LAN), as shown in Figure 1.
The standard specifies Medium Access Control
(MAC) and Physical Layer (PHY) for wireless
connectivity for fixed, portable and moving stations
within a local area. It operates using radio
technology at the ISM (Industrial, Scientific and
Medical) unlicensed frequency band of 2.4 GHz,
capable of providing radio coverage up to 100
meters in an open environment. The standard
considers a WLAN with 1, 2, 5.5, 11 and 54 Mbps
data payload communication capabilities, depending
on the radio modulation technique used to access the
medium, i.e. Direct Sequence (DSSS) or Frequency
Hopping Spread Spectrum (FHSS) (Institute of
Electrical and Electronic Engineering ,1999).
B. Propagation and Coverage
Mobile WLAN systems rely on their design and
appropriate radio planning for an uniform coverage
in an arbitrary environment, such as the University
Campus. The WLAN radio range is mainly
dependent on the channel physical and temporal
characteristics. In multimedia streaming
applications, the perceived quality of the decoded
content is greatly dependent on the quality of the
received radio signal. In the case of e-learning
applications, such as the one included in the b-
learning model proposed in this paper, sufficient
signal coverage in every access location is extremely
important to ensure acceptable quality of service
(QoS) delivered to learners. To this extent, a
measurement campaign was performed in order to
check the appropriateness of each potential access
location identified for the current survey.
2.3 WLAN Performance Evaluation
A. Practical Testing environment
The WLAN performance was evaluated for
multimedia streaming using the multimedia e-
content whose specific characteristics are described
in the next section.
The experimental system was comprised of a
multimedia streaming server, a content manager, one
AP and a laptop computer with a WLAN card. The
laptop was used as a client terminal with real-time
decoding capability of MPEG-2 streams. The audio
and video streams are delivered over RTP/UDP at a
bit rate of 2 Mbps and the control functions are
implemented over RTSP and RTCP (Wu et al.,
2001).
At regularly spaced points along various paths in
the intended coverage area, a streaming session was
initiated by the client terminal and the received
throughput was measured for 2 min. The received
radio signal power at the same locations was also
measured using a simple radio receiver (i.e.
spectrum analyser) coupled to an omni-directional
antenna. The results obtained from these two
different measurements provide a performance
factor of the WLAN streaming services, as discussed
in the following subsection.
B: Experimental results
The received radio signal power and the network
throughput for two selected paths (1 and 2) are
shown in Figures 2 and 3. Path 1 and 2 corresponds
to a line of sight (LOS) and non-line of sight
(NLOS) scenarios, respectively. Figure 2 shows that
along path 1, the throughput is kept almost constant
and equals the maximum bit rate of the MPEG-2
streams for all locations. Despite the fact that
received power decreases down to –57dBm, the
throughput is not affected. This is expected in path 1
because the user laptop is always in LOS and the
received power is still well above the minimum
threshold. A rather different behaviour is obtained
from measurements along path 2, as it can be shown
in figure 3. In this case the throughput suffers a
significant decrease after point 13, which
corresponds to a received power below –75dBm.
After this point there are two points (15 and 18)
where the measured throughput rises again to its
maximum value. Therefore, the reason for the higher
throughput at these points is in fact a stronger radio
signal.
The subjective QoS obtained at the various
measurement locations was found to have a strong
correlation with the throughput shown in figures 2
and 3. Whenever the total throughput does not reach
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the laptop, several video frames are skipped by the
MPEG-2 decoder, which results in unacceptable loss
of information for this type of application. Therefore
the minimum received power for an acceptable QoS
is approximately about -75dBm. Although this is not
an absolute figure, it can be used with a good level
of confidence if the WLAN characteristics do not
change significantly. Consequently, every access
location that did not comply with the minimum
received power outlined above was discarded for the
purpose of this study. This is of major importance in
e-Learning applications because low QoS leads to a
harmful contribution to the learning process. A more
detailed description of the WLAN performance was
recently presented by the authors in (Crespo et al.,
2004).
3 PEDAGOGICAL E-CONTENT
The e-learning component of the proposed b-
learning model includes multimedia e-content
specifically produced for this purpose. Since the
application in this work is a module on Electronic
Principles, this comprises problem solving methods
and examples of electronic circuit’s analysis, as
described in the next section. Considering the
specific characteristics of the communication
infrastructure (802.11g wireless LAN), in particular
its maximum transmission data rate of 54 Mbps, the
option was to use broadband e-content in order to
achieve low coding distortion. The e-content
produced was of two different types: i) documents
with short theoretical basics and proposed problems,
i.e. extended tutorial sheets, and ii) compressed
digital audiovisual content comprising the lecturer
explaining the solving methods employed and
solving the proposed problems by using a
whiteboard and appropriate markers of different
colours. Since the creation, delivery and use of the
first type of content is relatively simple, no further
reference will be made to it.
In regard to audiovisual content, an important
aspect to be considered from a technological point of
view is the characterisation in terms of motion and
image quality of the visual information. While the
first might be important to define the refreshment
rate used for pictures (temporal resolution), the
second is important for defining the image
resolution. Both of them partially define the video
signal quality and ought to be taken into account for
each type of application, in the light of the service
requirements and efficient use of resources (e.g.
bandwidth, storage capacity). The higher the spatial-
temporal resolution, the more demanding
requirements are imposed on information server
storage capacity and network bandwidth. Therefore,
in order to provide an acceptable video signal
quality and not waste resources, it is desirable to
adapt the video signal parameters to the application
requirements.
Figure 2: Received power and throughput analysis along
path 1.
Figure 3: Received power and throughput analysis along
path 2.
The audiovisual information comprises a lecturer
speaking, writing on a whiteboard and moving in
front of the whiteboard area. Figure 4 shows one
picture of the visual content used in this work. From
a semantic point of view, this scene contains two
visual objects with different semantic value for the
human observer: the lecturer and the whiteboard. In
regard to subjective quality of this visual scene, it
should be pointed out that motion smoothness is
more important than texture accuracy in the case of
the lecturer, whereas texture is much more important
than motion in the case of the whiteboard. However,
since in MPEG-2 (ITU-T, 1995) it is not possible to
distinguish between areas within the image, the
requirement of high spatial detail is dominant
because most of the semantic value lies in the
whiteboard. Here, is where the lecturer writes down
pedagogical content for supporting and
complementing the oral explanations, which results
in video signals of relatively slow motion and high
texture detail i.e. characters and diagrams written
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with a marker. This means that the spatial resolution
of the video signal must be high enough in order to
be easily understood and to prevent unwanted
learning difficult factors arising.
3.1 Digital Format and Compression
The audiovisual information is digitally captured
and compressed in the standard format MPEG-2
Main Level@Main Profile, as defined in the ITU-T
Recommendation H.262 (ITU-T, 1995). The video
resolution is 720x576@25Hz, 4:2:0 format, which
makes this type of e-content fully compatible with
several media distribution systems, such as Digital
Television (DTV) and Digital Versatile Disk (DVD).
The considerations outlined above with respect
to signal quality and resource usage were taken into
account to determine an appropriate bandwidth for
encoding the audio and video signals. An informal
subjective testing was carried out by six lecturers in
order to find out the best compromise between the
bit rate of compressed streams and the content
subjective quality (note that audio and video signal
quality is still dependent on the multimedia encoding
equipment). Then the minimum acceptable bit rate
was found to be 94 and 1816 kbps for audio and
video, respectively. This yields a total of about 2
Mbps after multiplexing into an MPEG-2
Programme Stream (ITU-T, 1995). Note that an
uncompressed video with the same spatial and
temporal resolutions produces a bit rate of
720x576x25x12= 124.416 Mbps and would require
55.9872 GBytes for storing one hour of video. Thus,
the need for using a compressed format becomes
obvious. Nevertheless, it should be noted that video
and audio compression degrades the original signals
introducing an increasing distortion with the
compression ratio.
To this extent, basic knowledge of audio and
video codecs characteristics, in addition to their
main parameters and implications on the target
application, is a requisite for achieving acceptable
quality performance. For example, a bit rate between
4 and 6 Mbps is enough to achieve good quality with
fast motion video.
3.2 e-Content Creation
In this work, three main requirements were defined
for generating e-content: i) the lecturers involved in
the process should not need to have any specific
technical skills, in order to make e-content creation
an easy task, ii) neither should it demand for extra
lecturing time effort, so that work overload can be
avoided; iii) post-production should not be necessary
in order make it cost effective. A similar approach is
described in (Schutz et al., 2003).
Figure 4: Example of visual content used for e-learning.
Two modes of content creation were envisaged
in the light of the above requirements. One of these
consists in real-time capturing of live classes where
the lecturer presents pedagogical content by using
the whiteboard and interacts with students. The
video camera is always placed at a fixed point,
where both the lecturer and the whiteboard are
always within the camera visual range and fixed
focus might be manually preset. If the whiteboard is
too wide so that camera pan is required, then a
remotely controlled camera is used with a limited
number of preset positions that can be dynamically
changed by the lecturer.
The other mode of e-content creation is to setup
dedicated recording sessions, where the lecturer acts
in front of the whiteboard as in a normal live class.
In this case, there are no students inside the
classroom, but a cameraman is present to operate the
system. A second lecturer is present in the classroom
monitoring the session in order to ensure the
correctness of the technical contents and to assure
that pedagogical guidelines are followed according
to predefined rules.
These two modes have different requirements
and result in e-content of different characteristics.
While the former does not require any technical
assistance at all, the latter needs a cameraman during
the recording sessions. However, despite the need
for extra resources, the latter results in video content
with smoother visual transitions and possible
zooming of selected areas within the whiteboard,
highlighting the most relevant areas. This is not
possible to achieve with the former because the
audiovisual content acquisition is almost fully
automatic.
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From a pedagogical point of view, the two
modes also provide different results. In the former,
the lecturer is within normal classroom context and
the session is not specifically oriented for e-content
generation. Consequently, the resulting e-content has
several non-interesting periods (e.g. some interaction
periods between teacher and students) which is
indeed counter-productive in e-learning, because
they contribute for diverting the learner’s focus from
the topic under study. This is not the case of the
latter e-content generating mode, because it is
exclusively produced for e-learning use, hence not
only all possible harmful contributions to the
learning process are not present, but also special
learning enhancement features might be included,
such as more emphasis on specific topics that in
general students face more difficulties.
In summary, the former method is less resource
consuming but also of lower pedagogical quality for
e-learning applications, while the latter requires
more resources but results in more adequate
pedagogical e-content. In this work the two e-
content generating modes were tested, but only the
latter was used in the context of this paper.
3.3 e-Content Adaptation to
Heterogeneous Environments
As it was mentioned before, this type of e-content is
easily adapted to broadband applications such as
DTV or DVD. However, if either lower bandwidth
communication channels or mobile terminals with
limited resources are used, then this type of e-
content cannot be delivered as it is. Instead, it must
be adapted according to the characteristics of the
user terminal and access network.
As an example, such an adaptation would be
required, when delivering the same e-content to
MPEG-4 capable terminals, where audiovisual
scenes might be comprised of different objects
characterised by their semantic value. In this case, it
is possible to transcode MPEG-2 video frames into
two MPEG-4 visual objects such that only the
whiteboard visual information and the audio are
delivered to end users (Santos et al., 2004).
Although in a different context, the importance of e-
content adaptation was recently addressed in (Wang,
2004).
The main characteristics of the video object
“whiteboard” are its relatively slow motion and high
texture detail. The slow motion results from the
human writing speed on such type of board, whereas
high spatial detail is a consequence of its specific
visual contents, i.e., characters and diagrams written
with a marker. Therefore, the object can be
efficiently compressed by reducing the original
temporal rates, so that more bits are allocated to
encode the texture information and thus enhancing
the signal quality. In regard to the “lecturer” object,
it should be stressed that motion smoothness is more
important than texture accuracy due to its intrinsic
nature and semantic value in e-learning context.
This adaptation process by transcoding was
objectively tested in order to evaluate the picture
quality under a significant transcoding ratio for
matching lower bandwidth wireless channels. A
video sequence originally encoded at 2Mbps was
transcoded into 500 kbps by using two different
schemes: i) straightforward transcoding from
MPEG-2 to MPEG-2 and from MPEG-2 to MPEG-
4, using a single rectangular object and ii)
segmentation based transcoding from MPEG-2
video signals into MPEG-4 visual objects (Santos et
al., 2004). In the latter case, the inherent
characteristics of each visual object were taken into
account, as already mentioned. Then, the same bit
rate was set for each video object but they were
encoded at different temporal rates. The “lecturer”
object was encoded at 25Hz whereas the
“whiteboard” object was encoded at 6.25Hz. For
comparison with the video frames, after decoding
the two objects these were combined to form frames
again.
As it can be observed in Figure 5, where the
Peak Signal to Noise Ratio (PSNR) is used to
measure the picture quality, the transcoding scheme
yields a good performance when comparing with
both references. By using different coding
parameters for each video object, the transcoded
pictures have better spatial quality in the whiteboard
area, mainly because of its reduced temporal rate,
which allows more bits to encode the texture. The
composition problem that arises when different
video objects are displayed at different frame rates
may be overcome by filling in the missing areas with
pixels from the surrounding area, though this is not
addressed in this paper. The same behaviour is
obtained for other transcoding ratios, which means
that this might be an useful adaptation method for
this type of e-content.
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4 A B-LEARNING APPROACH
FOR ELECTRONIC
PRINCIPLES
The proposed b-learning process is depicted in
Figure 6. This is based on a set of pedagogical
strategies with the purpose of creating a flexible
learning environment through complementary
learner-centred interactions. This pedagogic model
also aims at contributing to develop students' self-
learning skills, increase their learning independence
and possibly achieve financial returns by reducing
cost without compromising the learning outcome
quality. The different types of interaction that
comprise the pedagogic model are provided through
different pedagogical agents (Rickel et al., 1997),
such as the lecturer in classroom sessions, the
portable computer and e-content in e-learning
sessions, working group members in collaborative
sessions and the lab tutor in practical sessions. The
learning outcome, which is the student’s ability to
deal with electronic circuits including both
theoretical knowledge and practical skills, is reached
at the end of the whole pedagogical process.
4.1 Classroom Sessions
The classroom sessions are based on traditional face-
to-face interaction between students and lecturer.
The latter acts as the pedagogical agent in this type
of learning environment. The theoretical content is
presented by the lecturer using the whiteboard and
slides as supporting lecturing material. Each topic
corresponds to a different chapter in the text book,
which may also include related problem solving
methods to be applied later in both the e-learning
and collaborative sessions. In this type of session,
interaction between the lecturer and students is
asymmetric, because most of the time is spent by the
lecturer delivering knowledge to students. A smaller
percentage of the time is spent on questions, answers
and critical analysis involving the whole class.
Although this may not represent the most favourable
operating mode from a pedagogic point of view, in
practice it cannot be much different because of the
large number of students inside the classroom,
particularly in Portuguese scenarios (e.g. sometimes
over a hundred students).
Figure 5: Picture quality obtained after bandwidth
adaptation through transcoding.
4.2 e-Learning Session
The e-learning sessions introduce flexibility in the
learning experience and develop student skills and
self-awareness of their own learning process. In
these sessions students access e-content from a
streaming server, through the on-campus wireless
network without time or space constraints. The
laptop along with e-content act as the pedagogical
agent in these type of sessions, where students have
the opportunity of attending the recorded sessions to
learn problem solving methods, practical aspects
related to each particular topic and clarify what they
have not fully understood in previous learning
sessions. The pedagogical e-content is produced by
lecturers with significant teaching experience in the
subject such that special emphasis is put on those
particular aspects that usually raise more learning
difficulties.
4.3 Collaborative Sessions
In collaborative sessions, students are organised in
working groups where they join individual efforts to
solve proposed problems engaging in a
complementary learning experience. The learning
outcome is a contribution to improve their
knowledge and skills in dealing with different
aspects of the topic under study. These sessions may
be assisted by a teacher mainly for guiding the
students along their own learning process rather than
directly teaching them how to get to the final
Learning
Outcome
Classroom
Sessions
Collaborative
Sessions
Practical
Sessions
E-Learning
Sessions
Pedagogical Agent: teacher Pedagogical Agent: student
Pedagogical Agent:
computer/e-content
Pedagogical Agent:
student, tutor
Figure 6: The proposed b-learning model.
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solution. The resulting knowledge should be
obtained from the information already available at
this stage (in theoretical and e-learning sessions) and
its processing within the working group in the form
of student-to-student interaction. To this extent,
whenever the lecturer is present, he should only help
processing the information, offering alternative
visions on the same problem in order to favour the
development of critical and analytical skills.
4.4 Practical Sessions: Laboratory
Work
The last session of the learning process consists of
practical work in the Lab, where students compare
and analyse the real behaviour of electronic
components, circuits and systems studied in previous
sessions. This type of session is used to consolidate
the knowledge and develop practical skills through
experimentation and application of theoretical
concepts. As in the collaborative sessions, a tutor
might be present for guiding the students in their
learning process.
5 ASSESSMENT
The b-learning model was assessed through a
student survey where the emphasis was put on the e-
learning component, since this constitutes the new
component introduced in the existing pedagogical
process. A questionnaire, addressing several aspects
ranging from the technology in use to the possible
contribution of this learning model to increase the
success rate, was distributed among undergraduate
students on this particular course. The questionnaire
was answered by 72 students. All students initially
followed the learning guidelines given by the
lecturer, but it was observed that some of them have
not always strictly followed these, as one would
expect.
5.1 Results and Analysis
Analyses of results have shown that the b-learning
model was well accepted among students and in
some aspects even exceeded the expectations.
Remarkably, 22% of the students have classified the
wireless e-learning method as excellent, 49%
considered it as good, 18% as reasonable and only
11% have doubts if there was any advantage on
using it. When asked if their first opinion about the
available pedagogical e-content has changed as they
used it for learning, 40% of the students answered
that it revealed to be better than they initially
expected and the remaining ones kept the same
opinion as when they first started using the system.
None of the students said that it was worse than they
initially thought after using it regularly. Regarding
the technical point of view, they suggested
improvements, essentially on the quality of the
sound (42%) and image (24%). In regard to the
global quality of the system (sound, image,
computer, access and logistic conditions) 53%
considered it good, but 42% considered it just
reasonable.
At the end of the semester, only 36% of the
students have used the system according to the
predefined guidelines. The others accessed the e-
content only to clarify specific doubts or to catch up
with any unattended classes. Figure 7 illustrates
these results, which mean that the b-learning model
was not strictly followed by all students. Rather than
using the available e-content for improving their
knowledge through regular e-learning sessions, the
students seem to access the system only when they
feel it is really necessary.
From a pedagogical point of view, the opinion of
98% of the students is that the e-learning sessions
provide significant help in their own learning
process and 87% believe that such an e-learning
system applied to all course modules would be
beneficial for increasing the student success rate.
However, when questioned about the possibility of
replacing the conventional classes by e-learning
sessions the opinion is unanimous: the e-learning
session should not substitute traditional classroom
sessions. This opinion does not seem to be very
consistent with others, since 73% of the students
pointed out that an advantage of e-learning sessions
is the possibility of establishing their own learning
schedule and 87% refer that more flexibility in
managing their available time is an advantage. A
majority of 72% say that this type of e-learning did
not increment significantly the time spent on
learning when comparing with the traditional
classes.
The results show that students still have some
reluctance to engage in new pedagogical
methodologies. The knowledge obtained through
methodologies that are not strongly dependent of the
presence of the lecturer, reveals to be a process that
needs to be encouraged and advertised among
students.
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APPLICATIONS
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6 CONCLUSIONS
A novel b-learning approach supported by mobile
technology has been developed and tailored for
application in Electrical Engineering education.
Blended learning has been tested on an Electronic
based subject and results have demonstrated
relatively good outcomes when comparing to either
a traditional classroom model or one that only
embraces online delivery. On the one hand, the
approach seemed to be well accepted among
students in terms of the available technical
resources. On the other hand, student learning
outcomes were observed to be somewhat
conditioned by their lack of independence and
initiative, even though they could access e-content
anywhere on campus while on the move. There is a
need to respond to changing teaching needs more
rapidly than is currently possible. Combination of e-
learning and other learning modes were adopted to
match the available wireless technology and the
availability of lecturers, since the costs of creating
an online course may be prohibitive, both at the
initial development and in ongoing maintenance.
The proposed approach is established and provides a
continuing framework for new e-content
deliverables within the organisation.
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