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

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)

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

 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

MPEG-2 Codec

Desktop PC

Audio & Video

Infrastructure

e-Content

Generation

Wireless Access

e-Content Access

Information and

Communication

E-Content

Laptop PC

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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