HYBRID ONTOLOGY-BASED FEEDBACK E-LEARNING
SYSTEM FOR MOBILE COMPUTING
Ahmed Sameh, Abdalla Mahmoud and Amr Ibrahim
Department of Computer Science
The American University in Cairo
P.O.Box 2511, Cairo
Keywords: LOM, LMML, Dublin Core, Fragments, Metadata, RDF, Web Repositories, Mobile Computing.
Abstract: An E-Learning system that provides vast quantities of annotated resources (fragments or learning objects)
and produces semantically rich feedback is very desirable. It is an accepted psychological principle that
some of the essential elements needed for effective learning are custom learning and semantic feedback. In
this paper we are making use of a collection (ontology) of meta-data for the design of a custom E-Learning
system that also provides learners with effective semantic educational feedback support. The learning
domain is “Mobile Computing”. We define various concepts in the domain and the relationships among
them as the ontology, and built a system to utilize them in customizing the E-Learning process. The
ontology is also used to provide informative feedback from the system during learning and/or during
assessment. The focus in this research is on the representation of ontology using languages/grammars,
grammar analysis techniques, algorithms and AI mechanisms to customize the learning and create effective
feedbacks. The proposed mechanisms, based on Ontology; are used to assemble virtual courses and create a
rich supply of feedbacks, not only in assessment situations but also in the context of design-oriented
education. We are targeting feedbacks similar to ones in programming environments and design editors.
1 VIRTUAL COURSES
The proposed system aims to expose vast quantities
of annotated resources (fragments or learning
objects) that have been created over time and space
by educators and instructional designers to data-
mining end users in order for the latter to assemble
sequences of “learning objects” (virtual classes).
Towards this goal we are proposing an ontology-
based feedback model to achieve a number of high-
level objectives: Dynamically Generating On-
Demand Virtual Courses/Services, Providing
Component-based Fragments, and facilitating rich
Semantic Feedbacks.
An organization repository is a repository of course
components (fragments) at various levels-of-details.
As such, these fragments can be reused for several
courses and contexts and can be distributed over a
number of sites. A virtual course authoring process
points to various learning components (fragments).
A learning fragment is a self-contained, modular
piece of course material. It can be either passive or
active (e.g. live or recorded lecture). These
fragments are annotated (for example by author)
according to ontology metadata schema that provides
efficient mechanisms to retrieve fragments with
respect to the specific needs of a virtual course. With
similar details; administrators cooperate in building
various service repositories. This follows the new
direction in what is called “Semantic Web” .
An organization local architecture consists of
Repositories, a Mediator, Concept Storage
Fragments, Storage Systems, and Clients. The
Mediator provides transparent access for all client
requests to all distributed repositories fragments. The
huge amount of metadata we have to deal with
indicates the need for efficient storage and query
mechanisms. The repositories can be accessed either
synchronous or asynchronous. Customers can either
access their composed virtual courses/services either
on-line or off-line, in distance and/or conventional
education.
The development of electronic course material
suitable for different learners takes much effort and
incurs high costs. Furthermore, professional trainers
have huge expenses to keep course content up to
date. This problem occurs especially in areas where
knowledge and skills change rapidly, such as in the
Computer Science domain. Thus, we need new
approaches to support (semi-)automatic virtual
347
Sameh A., Mahmoud A. and Ibrahim A. (2006).
HYBRID ONTOLOGY-BASED FEEDBACK E-LEARNING SYSTEM FOR MOBILE COMPUTING.
In Proceedings of WEBIST 2006 - Second International Conference on Web Information Systems and Technologies - Society, e-Business and
e-Government / e-Learning, pages 347-356
DOI: 10.5220/0001247203470356
Copyright
c
SciTePress
course generation in order to keep up with current
knowledge and perhaps even to adapt materials to
individual user needs. In this proposal repositories
are used as infrastructure to support the automatic
generation of virtual courses from similar course
repositories, while also aiming to achieve a high
degree of reusability of course content. A popular,
promising approach is to dynamically compose
virtual courses “on-demand” within the course
repositories. The idea is to segment existing course
material (e.g., slides, text books, animations, videos)
into so-called learning fragments. Such learning
fragments represent typically self-contained units
that are appropriately annotated with metadata.
Tailored training virtual courses are requested and
generated "on-demand" by assembling single
fragments, such as in (Tendy,1998) (Kolb, 1984).
Using this approach that is similar to modularization
in software engineering, we intend to achieve a high
degree of reusable content, and have learning
fragments that can be used in new contexts. This
reduces costs for the development of real courses.
User adaptability is achieved by means of allowing
users to specify queries, and dynamically construct
courses. As a result, a course may contain fragments
from various sources such as textbooks, instructional
movies, or slides from several knowledge providers
(e.g. teachers) as well as fragments from similar
remote repositories. Note that there is a tradeoff
between granularity (size) of learning fragments,
reusability, and annotation effort. Having small units
of learning fragments increases the annotation effort,
but implies better reusability since small fragments
can be composed more flexible. The same can be
said about virtual services for
students/administrators.
Students can customize whatever they want to
learn according to their learning style, the amount of
time they wants to spend in a certain learning
session, the surrounding environment, their mode,
how deep they wants to dig into the subject, etc.
Based on the available metadata annotations, on-line
virtual courses are generated semi-automatically
from course repositories by selecting appropriate
course fragments and by structuring them into a
virtual course, which is a composition of fragments.
The selection and composition is based on a query
that specifies concepts to be taught and restrictions
(e.g., author, source, date of authoring). For these
specified concepts, any pre-knowledge concepts are
retrieved and appropriate fragments are selected.
This means that the virtual course structure is build
dynamically on the corresponding pre-knowledge
conditions of fragments to be selected. We call this
bottom-up approach, that stands in contrast to top-
down course composition, where the course structure
(e.g., a table of content) is static and given a priori.
Further, didactic, content-specific and course-
specific needs can be considered for the selection of
fragments. The structuring and selection processes
are strongly correlated. In case that no fragments are
found that map exactly to the restrictions (e.g., the
date of authoring is older than specified in the course
request), the algorithm selects fragments that do not
map optimally to the specification, but also fit to the
course. This proceeding avoids the ad hoc generation
of missing fragments for a requested course. As a
result, complete virtual courses can be generated. A
course end user also has the option to refine an
automatically composed virtual course. The
complete virtual course is then presented to the end
user who has access to a web portal.
In fact, research groups can open their own
repositories (e.g. Robotic-repository) where
fragments of group member’s contributions can be
stored in and annotated. Again, an end-user can
compose his virtual tour among these fragments. For
example, the AUC annual conference proceedings
can be fragmented and stored there.
2 SEMANTIC FEEDBACK
In a classroom learners and teachers can easily
interact, i.e. students can freely ask questions and
teachers usually know whether their students
understand (basic) concepts or problem solving
techniques. Feedback is an important component of
this interaction. Furthermore, educational material
can be continually improved using information from
the interaction between the lecture and the learners,
which results in a more efficient and effective way of
course development.
Feedback can be given to authors during virtual
course development and to learners during learning.
In the current generation of E-Learning systems,
automatically produced feedback is sparse, mostly
hard coded, not very valuable and almost only used
in question-answer situation.
In this paper we are introducing mechanisms –
based on ontologisms- to create a rich supply of
feedback, not only in question-answer situations but
also in the context of virtual courses composition.
Ontologisms are formal descriptions of shared
knowledge in a domain. With ontologisms we are
able to specify (1) the knowledge to be learned
(domain fragments and task knowledge) and (2) how
the knowledge should be learned (education). In
combining instances of these two types of
ontologisms, we hope that we (1) are able to create
WEBIST 2006 - E-LEARNING
348
(semi-) automatically valuable generic feedback to
learners during learning and to authors during virtual
course development, and (2) are able to provide the
authors with mechanisms to (easily) define domain
and task specific feedback to learners.
Feedback describes any communication or
procedure given to inform a learner of the accuracy
of a response, usually to an instructional question.
More general, feedback allows the comparison of
actual performance with some standard set of
performance. In technology-assisted instruction, it is
information presented to the learner after any input
with the purpose of shaping the perceptions of the
learner. Information presented via feedback in
instruction might include not only answer
correctness, but also other information such as
precision, timeliness, learning guidance, motivational
messages, background material, sequence
advisement, critical comparisons, and learning focus.
Feedback is given in the form of hints and
recommendations. Both a domain
conceptual/structural ontology as well as a
task/design ontology is used. The ontologisms are
enriched with axioms, and on the basis of the axioms
messages of various kinds can be generated when
authors violate certain specified constraints.
In our research we are generating generic, domain
and task feedback mechanisms that produce
semantically rich feedback to learners and authors
during learning and authoring. We distinguish two
types of feedback: (1) feedback given to a student
during learning, which we call student feedback, and
(2) feedback given to an author during course
authoring, which we call author feedback. The
generic feedback mechanisms use ontologisms as
arguments of the feedback engine. This is important,
because the development of feedback mechanisms is
time consuming and specialist work, and can be
reused for different ontologisms. Besides generic
feedback mechanisms we will provide mechanisms
by means of which authors can add more domain
and/or task specific feedback. In this research, we
focus on “Mobile Computing” domain.
We designed an E-Learning environment for
Mobile Computing courses, in which: (1) learners
are able to design artifacts of certain domains using
different types of languages, and (2) authors are able
to develop virtual courses. Learners as well as
authors receive semantically rich feedback during
learning, designing artifacts and developing virtual
courses.
For example, a student first has to learn the
concept (communication) network. Assume that a
network consists of links, nodes, a protocol and a
protocol driver. Each of these concepts consists of
sub-concepts. The domain ontology ‘communication
technology’ represents these in terms of a vocabulary
of concepts and a description of the relations
between the concepts (see figures 1-3). On the basis
of an education ontology, which describes the
learning tasks, the student is asked to list the
concepts and relate the concepts to each other (see
figure 1). Feedback is given about the completeness
and correctness of the list of concept and relations
using different balloon dialog patterns.
In a second step the learner is asked to design a
part of a local area network (LAN) using the network
model developed during the first step (see figures 2-
7). Instead of concepts, concrete instantiations must
be chosen and related to each other. The learner gets
feedback about the correctness of the instantiations
and the relations between the concepts using
different star/lamb/scroll dialog patterns. Some
protocols for example need a specific network
topology. There are various sequences of activities to
develop a network, each of them with its own
particular efficiency. The student gets feedback
about the chosen sequence of activities on the basis
of the task/design ontology. Further, the student
receives different types of feedback, for example
corrective/preventive feedback, critics and guiding.
All these feedback types are further customized to
the learning style of the learner.
An author develops and optimizes a virtual course
from learning fragments. He/she has to choose,
develop and/or adapt particular ontologisms and
develops related fragmented material like examples,
definitions, etc. (see figure 1). Based on analyses of
the domain, education and feedback ontologisms, the
author gets feedback, for example about: (1)
Completeness: A concept can be used but not
defined. Ideally, every concept is introduced
somewhere in the course, unless stated otherwise
already at the start of the course. This error can also
occur in the ontology for the course. (2) Timeliness:
A concept can be used before its definition. This
might not be an error if the author uses a top-down
approach rather than a bottom- up approach to
teaching, but issuing a warning is probably helpful.
Furthermore, if there is a large distance (measured
for example in number of pages, characters, or
concepts) between the use of a concept and its
definition in the top-down approach, this is probably
an error. (3) Synonyms: Concepts with different
names may have exactly the same definition. (4)
Homonyms: A concept may have multiple, different
definitions, sometimes valid depending on the
context.
The E-Learning environment consists of four
main components: a player for the student, an
HYBRID ONTOLOGY-BASED FEEDBACK E-LEARNING SYSTEM FOR MOBILE COMPUTING
349
authoring tool, a feedback engine and a set of
ontologisms as pluggable components (see figure 1).
The player consists of a design and learning
environment in which a student can learn concepts,
construct artifacts and solve problems. The authoring
tool consists of an authoring environment where the
author develops and maintains courses and course
related materials like ontologisms, examples and
feedback patterns. The feedback engine
automatically produces feedback to students as well
as to authors. The feedback engine produces generic
feedback and specific feedback. Generic feedback is
dependent of the ontologisms used and is applicable
to all design activities and artifacts (e.g. critic,
guidance, and corrective/preventive feedbacks).
Specific feedback is defined by the author and can be
more course, domain, modeling language or task
specific. To construct feedback, the feedback engine
uses the four argument ontologisms (concept,
structure, task, and design feedbacks). Since the
ontologisms are arguments, the feedback engine
doesn’t have to be changed if an ontology is changed
for another. The feedback engine can produce the
two types of feedback mentioned (student and author
feedback). To produce student and author feedback,
student and author activities are observed and
matched against the ontologisms mentioned.
3 ONTOLOGISMS
In the experimental “Mobile Computing” prototype,
fragmented metadata-based repositories that are
making use of four standards: Resource Description
Framework (RDF), IEEE LOM Metadata, Learning
Material Markup Language (LMML), and XML-
based Metadata are used to build the prototype. The
proposed prototype is providing gateways among
these standards.
RDF/RDFS (1-4) is deployed as one of the
underlying modeling languages to express
information about the learning objects (fragments or
components) contained in the repository, as well as
information about the relationships between these
learning objects (the ontologisms).
Each repository can for example store RDF
(Resource Description Framework) metadata from
arbitrary RDF schemas. Initial loading for a specific
virtual course is done by importing an RDF metadata
file (using XML syntax for example) based on this
course's RDFS schema. A simple cataloguing
(annotation) of its fragments can be deployed using
the Dublin Core metadata set (1-4). We can also port
these metadata to the LOM standard, using the
recently developed LOM-RDF-binding (1-4). With
RDF, we can describe for our purposes, how
modules, course units, corselets are related to each
other or which examples or exercises belong to a
course unit, RDF metadata used in this way are
called structural or relational metadata.
The IEEE LOM Metadata standard specifies the
syntax and semantics of Learning Object Metadata,
defined as the attributes required to fully/adequately
describe a Learning Object. Learning Objects are
defined here as any entity, digital or non-digital,
which can be used, re-used or referenced during
technology supported learning.
LMML (1-4) proved itself as a pioneer in this field
providing component-based development,
cooperative creation and re-utilization, as well as
personalization and adaptation of E-learning
contents. Considering both economic aspects and
the aim to maximize the success of learning, LMML
is up to the new requirements of supporting the
process of creation and maintenance for E-learning
contents as well as supporting the learning process
itself. Each E-learning application has its own
specific requirements structuring its contents.
The ARIADNE (1-4) Knowledge Pool standard is
a distributed repository for learning objects. It
encourages the share and reuse of such objects. An
indexation and query tool uses a set of metadata
elements to describe and enable search functionality
on learning objects. To ensure simplicity,
understandability and adaptability for the ARIADNE
community, data elements are grouped into six
categories:
• General: groups the general information that
describes the learning object such as document title,
Document language, etc.
• Semantics: groups elements that describe the
semantic classification of the learning object like
the science type, main discipline, sub discipline etc.
• Pedagogical: groups elements that describe the
pedagogic and educational characteristics of the
learning object such as semantic density, interactivity
level, etc.
• Technical: groups elements that describe the
technical requirements and characteristics of the
learning object like OS version, required disk space,
etc.
• Indexation: groups elements that describe the
general information about the metadata itself of the
learning object such as the identifier of the metadata
instance, metadata creation date, creator, etc.
• Annotations: groups elements that describe people
or organizations notes about learning objects like
annotator, language of annotations, and date of
annotation.
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4 MOBILE COMPUTING
PROTOTYPE
We have built a prototype system in the domain of
mobile computing to demonstrate the ideas of the
proposed model. Hybrid fragments of annotated
resources taken from (Amjad, 2004) are used in this
prototype. Fragments are encoded in the four
representations described above: Dublin cores, IEEE
LOM, Learning Material Markup language (LMML),
and ARIANE. Figure 1 shows how the underlying
ontologisms are used in the prototype to build virtual
courses.
Figures 2-11 show snapshots of the implemented
prototype. Figure 2 shows part of the Domain
Concept Ontology of “Mobile Computing” in
acronyms terminology with semantic feedback (By
clicking on an Akron you get the Balloon feedback
with colored links to further explanation). Figure 3
shows part of Domain Design Ontology of the
“Mobile Computing” in hybrid wired/wireless
networking with semantic feedback (The Lamb
feedback is always on during hybrid networking
design). Figure 4 shows part of Domain Task
Ontology of the “Mobile Computing” in Sensor
Networking with semantic feedback (By clicking on
any element you will get the scroll feedback). Figure
5 shows part of the Domain Design Ontology of the
“Mobile Computing” in Bluetooth networking with
semantic feedback (the scroll feedback is always on
during a Bluetooth network design). Figure 6 shows
part of the Domain Design Ontology of the “Mobile
Computing” in Wireless PANs Networking with
Semantic feedback as well as critics and guidance
feedback (a Ribbon banner is always on during a
design of a wireless PAN network). Figure 7 shows
part of the Domain Structural Ontology of the
“Mobile Computing” in wireless networks
classification with Semantic feedback (a Balloon
provides rich feedback once you click on any class in
the classification). Figure 8 shows part of the
Domain Design Ontology of the “Mobile
Computing” in Wireless LAN Configuration with
Semantic as well as generic critic and guidance
feedback (a star banner is always on during the
design of a wireless LAN). Figure 9 shows part of
the Domain Design Ontology of the “Mobile
Computing” in Positional and Voice Commerce
Design with Semantic as well as
corrective/preventive feedback (a Balloon banner
popes up upon demand during the design of the
network). Figure 10 shows part of the Domain
Design Ontology of the “Mobile Computing” in
wired/wireless network Design with Semantic as
well as corrective/preventive feedback ( a Balloon
banner is always on during the design of the
wired/wireless network). Figure 11 shows part of
Domain Task Ontology of the “Mobile Computing”
in wireless/Internet heterogeneous networking
Design with Semantic task/conceptual feedback (
Balloon banners with colored links for further
explanations are displayed).
5 CONCLUSION
In this paper, we have presented a flexible
course/service generation environment to take
advantage of re-conceptualization and re-utilization
of learning/service materials. Virtual
courses/services are dynamically generated on-
demand from fragments’ metadata entries stored in
the Repositories along with semantically powerful
feedbacks. The proposed model achieve the
following benefits:
-Costlessness: Simple interface. No preparative steps
needed
-Comprehensiveness: Allowing all players to find
each other and the existing repositories easily
(totality is promoted by costlessness)
-Wideness: Inter-Repositories brokerage for wider
collaborative scope
-Heterogeneity: Gathering contributors with different
naming schemes (taxonomies) in one collaboration
model
-Promotion: Encouraging the unification of the
namespace (deepening the common part)
-Flexibility: Repositories can join even partially
-Abstraction: Repositories encapsulate their details
-Semantically Rich Feedback: Four types of visual
feedbacks are available
REFERENCES
(1)http://www.mccombs.utexas.edu/kman/kmprin.html#hy
brid
(2)http://www.w3.org/2001/sw
(3)http://www.indstate.edu/styles/tstyle.html
(4)http://citeseer.nj.nec.com/context/1958738/0
Tendy S., Geiser W., 1998, The Search for Style: It All
Depends on Where You Look, National Forum of
Teacher Education Universal Journal, 9(1).
Kolb D.,1984, Experiential Learning: Experience as the
source of learning and development, New Jersey,
Prentice Hall.
Amjad U., Mobile Computing and Wireless
Communications, NGE, 2004
HYBRID ONTOLOGY-BASED FEEDBACK E-LEARNING SYSTEM FOR MOBILE COMPUTING
351
Figure 1: Example of Resource Annotation Structure.
M-Business, M-Government
M-Commerce P-Commerce V-Commerce
M-SCMs M-CRMs SMS MMS M-Portal
Symbian WAP MM IT WML VXM L J2M E BREW
Mobile IP MANET OMA ITU ETSI FCC
Zigbee UWB FSO Bluetooth WLL DECT HomeRF
Wi-Fi GPRS UM TS 802.11 802.16 802.15 WSN
OFDM FEC TDM A CDM A
Figure 2: Part of the Domain Concept Ontology of “Mobile Computing” in acorns terminology with semantic feedback (By
clicking on an Akron you get the Balloon feedback with colored links to further explanation)
.
W irele s s L A N
Cell
W irele s s L A N
Cell
W irele s s L A N
Cell
CentrexCentrex
Router
and
Firewall
Link to
P ub lic In ternet
T1
or
DSL
X
Y
Z
LAN Server
Fast Ethernet
LAN (Backbone)
1. N o physical net security
(server ID /PW )
2. N o physical net security
(server ID/PW + encryption)
3. Physical net security at APs
(optional
server ID /PW + encryption)
A
B
CD
W ired Ethernet
LAN
Figure 3: Part of Domain Design Ontology of the “Mobile Computing” in hybrid wired/wireless networking with semantic
feedback (The Lamb feedback is always on during hybrid networking design).
Voice XML means markup
language for describing
Music and encoding musical
notes. Some of …. most
Server ID
is used fo
r
WEBIST 2006 - E-LEARNING
352
Figure 4: Part of Domain Task Ontology of the “Mobile Computing” in Sensor Networking with semantic feedback (By
clicking on any element you will get the scroll feedback).
Figure 5: Part of the Domain Design Ontology of the “Mobile Computing” in Bluetooth networking with semantic
feedback (the scroll feedback is always on during a Bluetooth network design).
W ireless Sensor Networks
Network of
Tiny
Sensors
Network of
Tiny
Sensors
Network of
Powerful
Sensors
Powerful
server
Many R&D
efforts
Sensor = mote
Bluetooth
Cellular
Network
PSTN
Access
Point
Wired
LAN
Bluetooth Piconet
(1 M bps, 10 meters, mobile adhoc network)
No physical network security exists between this server and
the top layer powerful sensor nodes. Each node is a Mote dev
Such as Video
Ca
m
e
r
s,
aud
i
o
so
Routing
Protocols of
sensors net
Bluetooth stack
include layers of
data, packets
control….
Devices
with
commun
ication ..
HYBRID ONTOLOGY-BASED FEEDBACK E-LEARNING SYSTEM FOR MOBILE COMPUTING
353
Figure 6: Part of the Domain Design Ontology of the “Mobile Computing” in Wireless PANs Networking with Semantic
feedback as well as critics and guidance feedback (a Ribbon banner is always on during a design of a wireless PAN
network).
Figure 7: Part of the Domain Structural Ontology of the “Mobile Computing” in wireless networks classification with
Semantic feedback (a Balloon provides rich feedback once you click on any class in the classification).
Wireless PANs: Home Networking
Wireless LAN2
(Master/slave)
First Floor
= W ireless Adapter
Wireless connection
Wireless connection
Second Floor
Printer
Baby
Monitor
TV
Phone
Laptop
Laptop
xDSL, cable,
ISDN, or other
Main PC
Internet
Gateway
Players:
Bluetooth
Sensor networks
•UW B
802.11
Zigbees
HomeR/F (dead)
XDSL and
ISDN are
fast Internet
service
provider
protocols
used to
connect in
between fl
W ireless Netw orks
Satellite
Systems
Cellular
Networks
Wireless LANs
Example1:
GSM , 9.6 Kbps,
wide coverage
Example2:
3G, 2 Mbps,
wide coverage
Example1:
802.11b
11 Mbps,
100 Meters
Other
examples:
802.11g,
HiperLAN2
W ireless W ANs
Personal
Area
Networks
Business
LANs
Example1:
Bluetooth
1 Mbps,
10 Meters
Other examples:
wireless sensor
networks, UWB
Example1:
Motorola
Iridium
up to 64 Mbps
globally
Example 2:
Deep space
communication
Wireless
Local Loops
(Fixed Wireless)
Wireless MANs
Example1:
LMDS
37 Mbps,
2-4 Km
Example2:
FSO
1.25 Gbps
1-2 KM
Paging
Networks
Example1:
FLEX,
1.2 Kbps
Example2:
ReFLEX,
6.4Kbps
Used in
6.4K
bps
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354
Figure 8: Part of the Domain Design Ontology of the “Mobile Computing” in Wireless LAN Configuration with Semantic
as well as generic critique and guidance feedback (a star banner is always on during the design of a wireless LAN).
Figure 9: Part of the Domain Design Ontology of the “Mobile Computing” in Positional and Voice Commerce Design with
Semantic as well as corrective/preventive feedback (a Balloon banner popes up upon demand during the design of the
network).
Part of Domain
Task Ontology of
the “Mobile
Computing” in
wireless/Internet
heterogeneous
networking Design
with Semantic
task/conceptual
feedback ( Balloon
banners with
colored links for
further explanations
are displayed)
W ireless LA N C onfigurations
W ireless L A N 1
(peer-to -p eer)
Wired
LAN1
= W ire le s s L A N A d a p te r
W ireless connection
W ireless connection
W ireless L A N 2
(p e e r-to -p e e r)
A ccess P oint
as a repeater
W ireless L A N 3
(M aster/slave)
A ccess P oint
A ccess P oint
Wireless
LAN -LAN
Bridge
Wired
LAN2
Personal A rea
N etw ork (PA N )
Part of Domain Task Ontology Computing” in wireless/Internet
heterogeneous networking Design with Semantic task/conceptual
feedback (Balloon banners with colored links for further explanations are
displayed)
Data NetworkData Network
Voice O ver IPVoice O ver IP
W ireless
Phone
Network
P o sitio n a l a n d V o ic e C o m m e rc e
Wireless
Gateway
Com puter+
GPS
Wireless
Phone+GPS
GIS/Map
Voice
Portal
W ireless Phone
E n te rp ris e
A p p lic a tio n
Server
Partner
Network
Partner
Network
APPs
DBs
802.11 L A N
(o ffic e o r a
hotspot)
Web
Server
Public
In te rn e t
Public
In te rn e t
Mobile Computing in
wireless/Internet heterogeneous
networking Design with Semantic
task/conceptual feedback ( Balloon
banners with colored links for further
ex
p
lanations are dis
p
la
y
ed
)
Part of Domain Task Ontology of Computing” in wireless/Internet heterogeneous networking Design with
Semantic task/conceptual feedback ( Balloon banners with colored links for further explanations are displayed)
HYBRID ONTOLOGY-BASED FEEDBACK E-LEARNING SYSTEM FOR MOBILE COMPUTING
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Figure 10: Part of the Domain Design Ontology of the “Mobile Computing” in wired/wireless network Design with
Semantic as well as corrective/preventive feedback ( a Balloon banner is always on during the design of the wired/wireless
network).
Figure 11: Part of Domain Task Ontology of the “Mobile Computing” in wireless/Internet heterogeneous networking
Design with Semantic task/conceptual feedback (Balloon banners with colored links for further explanations are displayed).
Router
C ellu lar
Phone (W AP)
Solaris
(D ata)
Ethernet
LAN
M o re D etailed V iew
TCP
/IP
C atalo g
M iddlew are
(ODBC)
Op System
(U N IX )
TCP
/IP
Purchase
System
Middleware
(W eb Serv er) (O D B C )
Op System
(N T )
WAP
Stack
WML
Middleware
(M icrobrow ser )
Op System
(C elullar)
NT
(Business L ogic)
CGI
WAP
Gateway
W ireless
Network
P u b lic
In te rn e t
Router
wireless/Internet heterogeneous networking Design with Semantic task/conceptual
feedback ( Balloon banners with colored links for further explanations are displayed)
S am p le C o n fig uratio n
Wireless LAN1
(p e e r-to -p ee r)
Corporate
Backbone
= W ireless L A N A d ap ter
W ireless connection
W ired connection
W ire le s s L A N 2
(p ee r-to -p e e r)
A ccess Point
as a repeater
A ccess
Point
A ccess Point
Internet
Gateway and Firewall
Corporate
ATM
Network
= A T M S w itc h
Public
In te rn e t
Domain Task Ontology of the “Mobile Computing” in wireless/Internet heterogeneous networking Design with
Semantic task/conceptual feedback ( Balloon banners with colored links for further explanations are displayed)
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