Table Of ContentContent Management Middleware for the Support of
Distributed Teaching
Hariklia Tsalapatas1, John B Stav2 and Christos Kalantzis1
1University of Thessaly, Volos, Greece
2Sor Trondelag University College, Trondheim, Norway
htsalapa@uth.gr
john.b.stav@iaf.hist.no
ckalant@uth.gr
Abstract: eCMS is a web-based federated content management system for the support of distributed teaching
based on an open, distributed middleware architecture for the publication, discovery, retrieval, and integration of
educational material. The infrastructure supports the management of both standalone material and structured
courses, as well as the integration of existing organized external repositories. The infrastructure is complemented
with services targeting the specific needs of user groups involved in the e-Learning process, namely learners,
content providers, course managers, and repository administrators.
Keywords: e-Learning, distributed teaching, content management, middleware, integration, content reuse,
metadata, information discovery, federated, autonomy, services, scalability, 3-tier architecture, structured
courses, examination development, statistics analysis
1. Introduction user groups involved in the e-Learning
process, i.e. learners, content providers,
Asynchronous e-Learning overcomes
course managers, and repository
geographical and temporal constraints
administrators. eCMS supports standalone as
transforming learning into a process that can
well as distributed configurations, allowing
occur at the independently determined
installations to evolve into educational content
convenience of instructor and learner (Harris
portals and ensuring the autonomy of
D., DiPaolo A., Goodman J. 1994). Demand for
institutions participating in an extended eCMS
asynchronous e-Learning has been developing
educational network.
driven both by corporations and professionals
striving to remain competitive in a constantly
eCMS services for learners include information
evolving job market and by individuals seeking
discovery through metadata keyword
degrees, typically at the higher education and
searches, navigation through organized
post graduate level, but facing time and
content, participation in self-assessment
location constraints. Furthermore, content
examinations, educational module reviews,
management infrastructures are recently being
and on-line collaboration tools. Services for
used as a complementary educational tool in
content providers include optional content
traditional classroom education (e-Learning
hosting, metadata authoring wizards, and
2001) for the publication and dissemination of
support for the on-line development and
course related material.
management of structured courses as well as
multiple-choice examinations. The system
The success of asynchronous e-Learning
supports the reuse of content, possibly
relies on the effective management of the
developed by peers, facilitating the creation of
wealth of available educational content.
value-adding educational entities under the
Recognizing the importance of educational
control of the owning organizations and with
content management in distributed teaching,
respect to the intellectual property rights of
the eCMS project focused on a web-based
content developers. Services for repository
federated content management system for the
administrators include publisher and user
support of the distance education process. The
management, easy to use educational content
system is implemented on state-of-the-art
metadata indexing for information discovery
digital library technology for the management
purposes, and transparent gathering and
of heterogeneous, possibly distributed content
analysis of system use statistics aiming at the
located locally or on remote servers and
constant improvement of services and
managed by independent content masters.
published material.
The core of the system is open, distributed
middleware for the publication, discovery,
eCMS recognizes that course structuring often
retrieval, and integration of educational
reflects the pedagogical practices and internal
material. The infrastructure is complemented
organization of academic institutions and thus
with services targeting the specific needs of
may differ significantly from one organization to
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Electronic Journal of e-Learning Volume 2 Issue 2 2004 (281-292)
another. In addition, educational content transparent to each repository’s normal
contributors are typically professors who have operations. This feature stresses the federated
already well developed pedagogical practices, nature of eCMS networks as opposed to
existing material, and limited time to standalone content management
restructure content or teaching methods. configurations.
Course managers wish to convert material
used in traditional classroom settings to on-line To facilitate the on-line learning process eCMS
content with as few modifications as possible. offers a basic collaboration environment that
For the above reasons, success of an on-line enables learner-learner and learner-instructor
educational content publication service communication. Given the wealth of relevant
depends on its flexibility on course structuring. software and the fact that eCMS focuses on
Rather than enforcing a predefined structure, federated content management infrastructures
eCMS allows providers to organize course the collaboration environment is implemented
content in a manner that best fits their by taking advantage of available off-the-shelf
academic practices through the support of tools.
flexible tree-like course hierarchies with no
additional limitations. Course content is External learner groups consisting of
developed in private workspaces controlled by secondary school teachers and higher
the publishers. Thus publishers have the education learners in the north and south of
discretion to make content available to the Europe have tested the system with positive
general public when they feel that it is mature. results. However, the proposed infrastructure
Content can be published either as complete is independent of the targeted learner group
entities, e.g. an entire course including several and may be used in a wide range of e-
lectures, handouts, exercises, etc, or in parts. Learning initiatives, such as higher education,
This flexibility is necessary for the support of post graduate education, life long learning of
current teaching practices, which often involve professionals, training of trainers, etc.
the periodic publication of material. For
example, instructors often publish reading lists 2. eCMS Educational Content
before a lecture so that students can prepare
Management Middleware
for class discussion. Instructors publish class
presentations after the lecture as reference Figure 1 displays the eCMS educational
material. This process ensures that students content management node. Information is
reach their conclusions through class logically organized into separate data stores
participation instead of being fed information for metadata, content, and system statistics.
by the instructor. The business logic is separated from the data
and is implemented in a separate service layer
On the other hand, while organizations to ensure flexibility in educational offerings,
recognize the benefits of on-line content software updates, and interface improvements.
dissemination they are reluctant to publish
material through a system that they do not fully The Metadata Store holds a description record
control. The federated nature of the eCMS for each published educational module. The
middleware allows institutions to install and system supports optional hosting of material
locally manage an eCMS node that may into a designated Content Hosting Area.
optionally be connected to a larger eCMS Material is uploaded into the system through
network. Thus, educational institutions enjoy the Hosting Service. It is expected that this
maximum autonomy through the distribution of mechanism is typically used for the publication
metadata and content. eCMS nodes can be of standalone educational units originating
installed at the institution or the department from institutions that do not currently offer
level. That is, the separation of content into organized distance education programs or the
logical repositories is flexible and can be infrastructure and know-how to manage
decided by the educational institutions. content independently but still wish to publish
educational content through external services.
Finally, eCMS supports the integration of Finally the Statistics Store holds transparently
existing organized repositories through gathered statistics on system use. Analyzed
metadata importing and mapping agents, a statistics are available for review by both
feature not currently supported by available e- system administrators and course managers,
Learning management systems (Blackboard who may use the information to evaluate their
2003), (WebCT 2003). eCMS can be practices and identify points of improvement.
configured to periodically import external
repository metadata in a manner that is
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Hariklia Tsalapatas, John B Stav and Christos Kalantzis
Web-based User Interface
search retrieval statistics
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Metadata Metadata Course
Importing Generation Developer Hosting
Service
Publication
Service eCMS Node
CEoxllteecrntiaoln StCanodnatelonnt e CEoxllteecrntiaoln
Figure 1: eCMS system architecture
Users interact with the eCMS Content
Management Node through a web-based The Statistics Gathering and Analysis service
interface providing customized library views automatically collects statistics on the use of
targeting the needs of learners, content offered services during the regular eCMS
providers, course managers, and repository operation. Statistics include information on
administrators. keywords used in queries, metadata records
matched through queries, reviewed metadata
Content providers can publish educational records, and user information. The goal of this
material in one of the following ways: (i) operation is the constant improvement of the
through the eCMS Metadata Submission and system functionality and content, as described
Editing Wizard, a facility that guides publishers in more detail in section “System statistics”.
through the step-by-step generation of
metadata descriptions for educational entities. Finally, a collaboration environment developed
(ii) Through the eCMS Course Developer, through off-the-shelf tools facilitates
which supports the publication of structured communication between learners (e.g. group
courses through the development of metadata work) as well as learner-instructor interaction
descriptions for educational modules as well as (e.g. office hours) thus aiding the learning
the definition of parent-child relationships process. The tools consist of chat-rooms,
creating tree-like hierarchies of content. (iii) forums, and application sharing modules.
Through the Metadata Importing Wizard for the
transparent integration of external repository Additional Content Management Nodes are
metadata, thus enabling the publication supported to ensure scalability of the system
through the system of entire collections of as the amount of managed information
information in a manner that does not interfere increases. Each eCMS node manages a
with the external repository normal operations. distinct metadata collection and corresponding
content. As described in more detail in section
Learners have access to published content “Support for metadata distribution and
through search and navigation interfaces that distributed queries”, distributed information is
support text-based queries against the periodically and transparently synchronized to
educational metadata. The system is ensure that users have access to the entirety
extensible to support text-based queries of the distributed content through an interface
against content, for example the content of a that hides the underlying system complexity.
text file or a file stored in a proprietary format
such as PDF. Content may be retrieved The system is designed as a 3-tier web-based
through the Information Delivery Service and application to ensure modularity of offered
presented to the learner in an appropriate services and minimum requirements on the
format depending on the storage method and user side. The back end (server side) of the
the intended use of the module (image, text, architecture serves as metadata, content, and
video, etc). statistics storage. Metadata and content is
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Electronic Journal of e-Learning Volume 2 Issue 2 2004 (281-292)
published on the web through a commercial structuring constraints. A hierarchical approach
Application Server. The middle tier implements has been adopted. The providers may decide
the business logic as servlets for specific the types of educational modules they will use
services. The front end (client side) is for course structuring purposes. Examples of
developed as JSP applications. The 3-tier currently supported module types include
structure disengages the logic from the course, module, section, and subsection.
interface, which ensures easy adaptation of However, the supported educational module
services and user screens for addressing the types are dynamically managed by eCMS
needs of additional target groups. administrators, as opposed to being hard-
coded into the system, and may be easily
Figure 2 displays the 3-tier implementation. As extended through straightforward on-line
shown in the figure, independent services and services. Thus, an institution that wishes a
interfaces are developed for each of the different structure, for example lecture driven
identified target user groups that participate in as opposed to the current book-content index
the asynchronous e-Learning process: Public table inspired one, can easily implement it.
Services aimed at learners, Provider Services
aimed at content providers and course Figure 3 displays the representation of
managers, and Administrator Services aimed structured courses in the eCMS system. In the
at repository administrators, who manage the presented example a number of independent
eCMS nodes. modules are displayed, interconnected with
“contains” parent-child relationships. Thus,
modules published through the system may be
reused, provided that the owning organization
permits. This example displays two courses:
“Computing” which includes “Computer
Architecture” and “Desktop Tools” (e.g. a lab),
which in turn includes “Imaging”, “Doc Editing”,
and “Spread Sheets”. “European
Figure 2: The 3-Tier implementation Computer Imaging
Arch
3. Course structure
One of the key difficulties and hindrances for Computing DTeoskotlos p EdDioticn g
publishing content, particularly already existing
modules, into e-Learning libraries is the fact Computer Spread
Basics Sheets
that many systems support a very specific
course-structuring model. At first glance this European 15th
may seem as a feature that simplifies the History Century
publication process and guides publishers
through content development. However, this Figure 3: eCMS course structure supporting
choice may prove to be a significant flexibility and module reuse
disadvantage when academic institutions wish History” includes a module for a historic period
to create distance education programs based and is reusing parts of “Computing” to provide
on existing content and educational practices. learners with basic desktop skills. Reuse of
These programs are typically developed by educational modules is a value-adding function
professors who on the one hand have very that takes advantage of the federated
limited time and on the other have already well distributed library nature of the eCMS system,
developed teaching practices that they wish to which is not available in standalone systems.
transfer to e-Learning courses. Furthermore, in Information reuse can result in the dramatic
a lot of situations the structuring of courses increase of content published through the
may represent a larger view on the educational system through combinations targting the
process adopted at an institutional level. needs of different learner groups.
It becomes apparent that for the success of 4. Educational content metadata
any open federated library for educational
content flexibility in the structuring of courses is Figure 4 displays a high level overview of the
a vital feature that encourages content eCMS Educational Module metadata schema.
publication. For this reason, the eCMS system The metadata schema has been developed
allows maximum flexibility to content providers taking into account earlier work in this area
on the structuring of material. eCMS achieves (The Dublin Core), (ETB), (Learning
this flexibility by imposing the least possible Technology Standards Committee 2000),
www.ejel.org 284 ©Academic Conferences Limited
Hariklia Tsalapatas, John B Stav and Christos Kalantzis
(Nikolau C., Georgakopoulos G., Tsalapatas H.
2000). Past work on metadata definitions has The Module Status Codes table enables the
been extended to support detailed descriptions effective management of educational modules
of structured courses and examinations, as by providing a means of identifying entities that
well as course hierarchies. are under construction, completed, public, or
available for reuse by other content providers.
The information is organized through relational This information may be used to customize the
database tables. Each published educational presentation of information to users. For
entity corresponds to a record in the Metadata example, learners may only access public
table and is uniquely identified. Information is modules whereas publishers have access to
also maintained on Publishers (e.g. the their own records but may only reuse modules
Department of Computer Engineering) as well developed by others if these modules are
as the Institutions the Publishers belong to marked as “available for reuse” by the owning
(e.g. the University of Thessaly). More than organization. The status code granularity is at
one Publisher may be associated with each the educational module level, as opposed to
Institution, thus creating a hierarchy of the course level, implying that parts of a course
Publishers in the organization of published may be marked as “completed” while other
educational modules. This hierarchy allows parts may be marked as “under construction”
additional granularity in the organization of and others as “public” to ensure maximum
content in local collections within an academic flexibility in course presentation. Status codes,
institution. similarly to educational module types, are
dynamically managed through on-line
Information is organized in Thematic Areas for functions, ensuring the straightforward
navigation and information discovery modification of existing and the addition of new
purposes. The supported Thematic Areas are ones as needed.
kept in a corresponding table, which is easily
updateable through available on-line services Security information is held in a separate
for repository administrators. Managing space in the schema and includes user
dynamically information on thematic areas accounts and groups that control access to
allows the creation of user-friendly information content and metadata in the system
discovery interfaces. The value of such repositories.
flexibility becomes clearer at the face of
growing educational repository content leading In order to support distribution of metadata, a
to the need of effective interfaces for feature that supports the autonomy of
information discovery. participating organizations as well as efficient
queries against the entire content space, the
eCMS system maintains a directory of
available repositories connected into a wider
eCMS network. The directory is used for
metadata synchronization and caching as
described in more detail in section “Support for
metadata distribution and distributed queries”.
Finally, text-based indexes are built on the
Module Metadata to allow free-text search.
Indexes are built on a set of metadata fields
Figure 4: Overview of eCMS educational
defined as searchable, while regular SQL
content metadata schema
queries are supported against the entire
The Module Type table holds information on
metadata record description. Examples of
the types of educational modules supported by
searchable metadata fields include a course’s
the eCMS system (e.g. courses, chapters,
title, author, summary, and keywords. Non-
sections, subsections, etc). The table enables
searchable metadata fields are the ones that
flexible course structures as the update of
describe details about an educational module,
supported module types and the addition of
such as course prerequisites, class-meeting
new ones is dynamic and involves simple
schedules, recommended bandwidth for
database operations through on-line functions
accessing the material, required course
for repository administrators. Course structure
examinations, etc.
is maintained through the Module Hierarchy
table, which holds parent-child relationships
forming tree-like hierarchies as described
above.
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Electronic Journal of e-Learning Volume 2 Issue 2 2004 (281-292)
5. Summary of eCMS services for ° Learner registration to the eCMS
the support of distributed system.
teaching ° Personal data and personal eCMS
account editing.
The following sections provide a high-level
(cid:131) Feedback forms on the eCMS services:
overview of the eCMS services implemented
on the educational content management ° On-line eCMS service questionnaire.
infrastructure described in earlier sections. ° Email-based feedback.
Services are customized for each targeted (cid:131) Services manual.
user group, namely learners, content
providers, course managers, and repository 5.2 Additional services for
administrators.
educational content providers:
5.1 Services for learners: In addition to the above services for learners,
the following are available for content
(cid:131) Querying support:
providers:
° Free-text search, which is the most (cid:131) Private workspaces for content
common and easiest to use development.
information discovery method.
(cid:131) On-line step-by-step metadata generation
° Search with options, used for and publication.
increased search result accuracy by
(cid:131) Management of educational content
matching user-entered keywords
metadata (editing, deleting).
against specific metadata fields as
(cid:131) Optional content hosting.
opposed to the entire metadata record
description; for example matching (cid:131) Access to learner educational content
particular keywords against an reviews and ratings aimed as an aid to the
educational module’s title. instructor for the constant improvement of
the published material.
° Search by eCMS record ID, useful for
the quick access of frequently used
5.3 Additional services for course
records.
managers:
(cid:131) Navigation:
° By publisher, for example by academic (cid:131) On-line structured course developer and
institution or by department. editor.
° By thematic area. (cid:131) On-line multiple-choice examination
developer and editor.
° By author or course instructor.
(cid:131) Collaboration environment:
5.4 Additional services for repository
° Chat-rooms for real-time quick administrators:
communications.
(cid:131) User account and group management.
° Forums for the support of discussions.
(cid:131) Supported educational module type
° Application sharing, for the
management.
collaboration on common projects.
Examples include collaborative work (cid:131) Institution and publisher management.
(modification and review) on shared (cid:131) On-line text-based metadata indexing.
files by users in different locations.
(cid:131) Importing of organized external
(cid:131) Participation in self-assessment multiple- repositories and mapping of external to
choice examinations. eCMS metadata.
(cid:131) Educational module reviews, which can be (cid:131) Support for the efficient distribution of
useful to other students wishing, for metadata and content through remote
example, to participate in a course: metadata caching.
° Submission of module ratings on a The following sections provide more details on
predefined scale of 1 to 5. key eCMS services and features. Additional
° Submission of text reviews with the information can be found in the eCMS Design
student’s opinion on the quality and and Implementation Reports (Tsalapata H.,
applicability of a module’s content. Brna P., Stav J. 2002, Tsalapata H., Kalantzis
C., Brna P., Stav J. 2003).
(cid:131) Management of personal record in eCMS:
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Hariklia Tsalapatas, John B Stav and Christos Kalantzis
6. Course developer and editor hand-ins, instructor availability, and other
information. Subsequently, providers are
The eCMS Course Developer and Editor
requested to add educational modules to the
utilities are part of the eCMS content and
course.
metadata publication services. Since they
Course sub-modules may be:
constitute an important aspect of the eCMS
(cid:131) New entities that the provider creates
system, they are discussed as separate
recursively at the time of course creation,
entities.
or
(cid:131) Existing entities already published through
6.1 Course developer
eCMS, which the provider reuses.
The eCMS Course Developer facilitates the In the case of a new entity, the provider
on-line construction of structured courses. This creates a metadata description for the module
value-adding functionality enables providers to (3) and either associates the module with a
make the most of published content by remote content address or optionally uploads
supporting the creation of new structured the corresponding content into the eCMS
entities either using new modules or based on repositories.
already published content. The service
complements the eCMS Metadata Submission The provider may reuse an already published
and Editing Wizard for the publication of entity as a sub-module of the course under
standalone educational modules to create a development by selecting the entity’s title from
complete on-line content authoring a drop-down list (3). Reusable entities may be:
environment. (cid:131) Entities that are owned by the provider, in
which case the provider has by default full
To ensure maximum flexibility on course rights, or
structuring the eCMS Course Developer
(cid:131) Entities that are owned by other providers
adopts a recursive top-down construction
and have been marked by their owners as
approach for the creation of tree-like
“available for reuse”.
hierarchies. In addition, the tool supports the
Once the sub-module has been created a
possibility of information reuse. The approach
parent-child relationship between the existing
is displayed in Figure 5. To gain access to the
node and the newly created sub-module is
service, providers must log into the eCMS
automatically inserted into the eCMS Course
system with their user account (1). The first
Structure area, extending the course hierarchy.
step of course creation is the submission of a
general metadata description for the course
The above process is repeated recursively in a
that documents the course title, the thematic
depth-first manner until the course is
area, the covered topics, the targeted
completed. Upon completion the provider may
audience, the required background on the
review the structure and use the Course Editor
learner’s behalf, the required effort for
to make any necessary
completing the course work, examinations,
changes/improvements.
Figure 5: Course developer and editor
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Electronic Journal of e-Learning Volume 2 Issue 2 2004 (281-292)
6.2 Course editor rooted at the node is visible only to the
owner / publisher.
The eCMS Course Editor complements the
(cid:131) Allow reuse of a node: This function moves
Course Developer to form a complete
a node and all its children to level “reuse
structured-course authoring tool. Through the
allowed”. Upon completion other
Course Editor providers may perform the
publishers may reuse the sub-tree rooted
following operations:
at the node for the development of value-
(cid:131) Edit the metadata description of a node in
adding educational entities.
a course hierarchy: Both the top level
“course” description and the inner “course (cid:131) Delete a node: This function deletes a
module” descriptions can be edited. node and all of its children. Also, it deletes
all parent-child relationships between the
(cid:131) Upload new content and associate it with a
node and its children and between the
node in a course hierarchy: This function
node and its parents and repeats this
allows the update of the content itself, and
operation recursively for each child. Upon
complements metadata updates.
completion the sub-tree rooted at the node
(cid:131) Publish a node: This function moves a
is deleted.
node and all its children to level “public”.
(cid:131) Detach a node: This function detaches a
Upon completion the sub-tree rooted at the
node, i.e. removes the corresponding
node is visible by the general public.
parent-child relationship. The difference
(cid:131) Hide a node from the public: This function
with the delete operation is that no nodes
moves a node and all its children to level
or other relationships are deleted. Figure 6
“complete”. Upon completion the sub-tree
displays the result of detaching Node B
from Node A.
A A
B
B
Figure 6: Node Detachment
• Add a node: This function inserts a new node in the course hierarchy at a specific location.
The new node can be added before or after a specific node in the existing course hierarchy.
Figure 7 displays the result of adding Node C before Node B.
A A
B C
B
Figure 7: Node Insertion
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Hariklia Tsalapatas, John B Stav and Christos Kalantzis
All actions described above are allowed on additional questions through the Examination
nodes that are owned by the publisher. During Question Wizard.
the recursive execution of the operations on a
sub-tree only nodes that are owned by the 8. Support for metadata
publisher are affected. Nodes that are part of
distribution and distributed
the sub-tree and are not owned by the
queries
publisher, i.e. they are reused, are not altered
in any way. In order to ensure autonomy of participating
organizations, eCMS supports the installation
7. Examination developer and of more than one independently managed
editor eCMS nodes optionally interconnected into a
federated digital library of educational content.
The eCMS Examination Developer and Editor Thus, institutions may install an eCMS node in
is an on-line authoring tool that supports their premises and manage it through the
course managers in the development of provided Repository Administrator services.
multiple-choice self-assessment examinations Remote eCMS nodes may be easily connected
for learners. The examinations may or may not into a wider eCMS network through the support
be associated with courses or other content for Metadata Distribution and Distributed
published through eCMS and may be Queries. This feature ensures that publishers
incorporated into a course hierarchy. may get the best of both worlds: autonomy in
the management of the content, scalability with
In a manner similar to the one used for course respect to metadata volume, and participation
development, examination development is in educational networks.
achieved through a top-down approach. A
general description of the examination is eCMS hides the complexity of the federated
created first, in which the developer may content management infrastructure from users,
document the scope of the examination, the who may submit a query through an eCMS
knowledge being assessed, the educational entry point and receive merged results of query
material it is associated with, and other hits from all eCMS nodes. Users may review
information. An eCMS metadata record is query results from a single list without being
automatically created for the examination and required to know details about the nodes that
may be used as a handle for optionally manage individual records.
incorporating the examination into a course
hierarchy, as mentioned above. Two approaches were considered for the
implementation of metadata distribution and
Once the general examination description is distributed query support:
complete, the eCMS Examination Developer (cid:131) Distributed queries: This approach
guides the user through the addition of involves the propagation of a user query,
multiple-choice questions to the examination which has been entered through an eCMS
through the Examination Question Wizard. For entry point, to all eCMS nodes, the
each question, the wizard prompts for the execution of the query locally at each
following information: eCMS node, the collection of query results
(cid:131) The question text, to be presented to the from all nodes, the merging of results, and
learner taking the examination. the presentation of a single, merged result
(cid:131) Up to 5 possible answer texts. list to the user.
(cid:131) The correct answer. (cid:131) Metadata caching: This approach involves
“synchronization” of eCMS metadata
(cid:131) An optional hint for the correct answer, to
repositories. Specifically, it involves
be presented to the learner.
caching of remote eCMS metadata, which
(cid:131) An optional eCMS address (URL) of the
results in equivalent eCMS nodes, i.e. into
educational module where the correct
eCMS nodes that hold the same metadata
answer may be located, to be presented to
information, some of which is local and
the learner.
some replicated from remote servers.
This process is repeated for each question to
The second approach, i.e. metadata caching,
be added to the examination.
has been implemented in the eCMS system to
alleviate the need for remote queries, thus
The Examination Editor supports the editing of
resulting in faster query responses.
examination metadata description fields, the
deletion of questions, and the insertion of
www.ejel.org 289 ISSN 1479-4403
Electronic Journal of e-Learning Volume 2 Issue 2 2004 (281-292)
The Repository Synchronization service is infrastructure, the organization of content, and
available on-line to repository administrators, the costs and benefits of the provided services
who may invoke it through a simple click of a to the users. For this reason, in addition to
button. It may also be programmed by gathering user input through questionnaires
administrators to be executed periodically, e.g. and email, statistics gathering and analysis
nightly. Repository synchronization is achieved mechanisms have been developed that
through the following steps: operate transparently and gather information
1 Identification of the addresses of all remote on system use.
repositories connected into an eCMS
network. Gathered statistics currently include the
2 For each remote repository: following:
(cid:131) Query keywords entered by users, for both
a Deletion of the locally cached
basic search and search with options
information that originates from the
specific repository. (cid:131) eCMS identifiers of records matched by
queries
b Importing of the remote repository’s
metadata records. (cid:131) Reviewed metadata records of educational
modules
c Importing of the remote repository’s
course hierarchy structures. (cid:131) User information
To facilitate the above actions eCMS stores, (cid:131) Date of statistics record entry
for each metadata record, information on the The above information is gathered by
eCMS repository of origin, i.e. the repository automatically inserting records into a
where the record is stored and managed. designated Raw Statistics area of the Statistics
Other repositories simply cache copies of the Store each time a user enters a query or
original records, thus ensuring the integrity of reviews an educational module. Once
metadata information. analysed, the statistics information is moved to
a corresponding Analysed Statistics area of
9. External repository integration the Statistics Store. The analysed statistics
provide views and summaries of the gathered
External organized educational content raw information in a format that can be easily
repositories, which have their own educational interpreted by repository administrators and
metadata definition sets, may be integrated course providers and can provide valuable
into eCMS through the Metadata Importing feedback leading to system and service
Wizard. The wizard operates transparently to improvements, such as more accurate
the external repository’s normal operation as a metadata information and interfaces that are
background demon that may be configured to easier to use.
poll the external repository periodically, e.g.
nightly or weekly. The wizard imports external Table 1 displays examples of analysed
metadata records, maps the metadata to the statistics and possible improvements they can
eCMS metadata definition set through a lead to.
mapping scheme that is specific to the external
Table 1: Analysed statistics and resulting
repository, and stores the mapped metadata
possible system improvements
into the Metadata Store as eCMS records that
are subsequently indexed through the eCMS Analysed Possible System and
metadata free-text indexer. Statistics Service Improvements
Occurrences of a
This functionality requires cooperation
particular keyword
between the eCMS and external repository in basic free-text
administrators, who must provide the mapping queries Adjustment of the navigation
of the external repository metadata fields onto interface according to
Occurrences of a
the eCMS metadata definition set. frequently used keywords.
particular keyword
in particular fields
This functionality allows eCMS installations to for queries with
evolve into e-Learning portals for the access of options
information originating from independent
Rarely matched records may
sources.
imply unintuitive metadata
eCMS identifiers of descriptions. The metadata
10. System statistics matched records descriptions of such records
may have to be modified to
Gathering and analysis of statistics can lead to
ensure easier discovery.
valuable feedback on the system
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