An Open E-Learning Authoring Environment

Manuele Kirsch Pinheiro, José Valdeni de Lima, Nina Edelweiss, Nabil Layaïda, Tayeb Lemlouma

Abstract

The goal of this paper is to show a complete environment for authoring of e-learning courses using open softwares and web standards. This authoring environment uses modern technologies, as XML, SMIL and WebDAV, to connect professionals for cooperatively create material for e-learning courses, using open softwares to produce a very low cost environment. The proposed environment uses a workflow to control the authoring process and helps the professionals involved in the course creation.

Keywords : E-learning, Workflow, Web Applications, Open Learning Systems, Cooperative Environment.

1 Introduction

The creation of good didactic material is not an easy task. When e-learning is concerned, it is even worst. When multimedia and other technologies are used, a tendency nowadays, the complexity of the system grows up more and more. In order to deal with this complexity, the process of didactic material authoring for e-leaning, what we call in this paper "e-learning authoring", often becomes a cooperative process. In this process, a group of educators and technical people is usually composed to idealize, design and deploy the environment needs and contents.

Besides this, we should remark the presence of Web technologies deployed at a world wide level. The use of the WWW for training and e-leaning purposes is unquestionable and is growing even more with the new Web technologies, like XML and SMIL. However, the WWW should not be used only as a medium to present e-learning information. We shall use it as an authoring environment, serving to connect the authoring group, sometimes geographically distributed. This allows us to profit the technologies, standards and available products for the Web in the authoring process. All this together allows a better content production support. To reach this goal, we decided to use some of these technologies, standards and products to build an experimental open environment for e-learning authoring.

We present in this paper this cooperative authoring environment for e-learning based on the WWW. We purpose the use of modern technologies, like XML, SMIL and WebDAV, and open softwares, like Amaya and Annotea, to create a low cost environment for e-learning. Moreover, on top of these elements, we propose the use of a workflow engine to control the creation of courses in this environment. The workflow will guide all the authoring process, while coordinating the cooperation among authors, thus helping the group to efficiently produce their e-learning material. The result, as we show in this paper, is an environment divided in four basic elements: a workflow engine that controls the other elements, a web authoring tool, multimedia tools, and a set of functions supporting cooperative work. Those elements interact as shown in the Figure 1. In a first moment (1), the coordinator of the group defines the workflow for the e-learning authoring process, using a workflow editor. This coordinator submits the workflow description created by him in the server (2), where a workflow engine will use this description to control the authoring process. After that, the course authors will be able to follow this process, by interacting with the workflow engine (3), while they are using the tools to create the course's web pages (4) and multimedia resources (5).

Environment overview

Figure 1 : Overview of the proposed environment

We discuss all the elements presented in Figure 1 separately: in the Section 2 we show how the web pages are constructed (the web authoring tool); in Section 3, we add to it the multimedia production (the multimedia authoring tools); Section 4 shows the cooperative aspects of the purposed environment. Section 5 presents the workflow engine, which brings together all the elements. Finally, in Section 6, we present some future considerations about the course execution, and in Section 7, some preliminaries conclusions.

2 Web Authoring

The first element of the proposed environment is a web editor to create the web pages for our e-learning course. Looking for a good open source tool, we have chosen Amaya, a browser/authoring tool developed by W3C that allows us to publish documents on the Web. Amaya is a complete web browsing and authoring environment and comes equipped with a "WYSIWYG style" of interface, similar to that of the most popular commercial browsers [VATTON 2001]. As it is used by W3C to demonstrate and test new developments in Web technologies, Amaya includes very modern features, like XML and CSS. Thus, using Amaya, users can generate pages in HTML and XHTML, generate CSS style sheets, MathML expressions and SVG vector graphics. Consequently, our users can build powerful web pages for their e-learning courses, using a very lightweight tool. Moreover, as Amaya only uses web standards, all the pages shall be viewed through any modern web browser.

Amaya also implements an Annotea client [KOVUNEN 2001], an application for collaborative annotations based on state of art technologies like RDF and XPointer. Using this client, users involved in the e-learning authoring process can do annotations in their courses' documents. With these annotations, the users dispose of an important cooperative function and an expressive communication channel, which makes possible to them to insert and to exchange comments, ideas, experiences, etc. Complementing this web authoring tool, there should be a well configured HTTP server. This server should permit the users to publish their pages and to make these pages available for the co-authors, allowing the construction of the cooperative environment needed for the e-learning authoring process. The same server may also enrich this cooperative environment by the addition of one Annotea server, as we will discuss in the Section 4.

All these web authoring features purposed in our environment can be visualized in Figure 2. In this figure, both the client and the server side may be seen. On the client side, there is Amaya, together with Annotea. And on the server side, the Annotea server and a full web server. We have been using Apache as our HTTP server [Apache-HTTPD 2001]. Apache is a very popular open source server. With Apache it is possible to deal with HTTP PUT requests, which allows the users to publish their material, and also support WebDAV requests (see Section 4). Moreover, the W3C's Annotea server uses the same HTTP server and other open tools, like Perl language and MySQL database. Therefore, we should remark that, using Amaya, we use only well-defined web standards, what improves the portability of the created documents, and forms, with the server, a set of web authoring resources that uses only open softwares.

web authoring environment

Figure 2 - Web authoring features

3 Multimedia Tools

As we mentioned earlier, the importance of multimedia for e-learning is unquestionable. There is no way to support e-learning without including multimedia in the courses material. There are many tools to create medias, like images, sounds and videos, and thousands of medias already available over the Internet. But, just putting all medias together in the same document will not necessarily enhance the course quality. Those medias should be synchronized to make a good presentation of the document and to reflect over time the content used by teachers, like gestures, demonstrations and examples. We concentrated our work here in the use of multimedia synchronization tools, which give to the authors the possibility to coordinate and construct rich multimedia presentations.

One of most recent technologies for multimedia synchronization is the SMIL language. The SMIL (Synchronized Multimedia Integration Language) [MICHEL 2001] is a XML based language proposed by W3C that permits the integration of many different media types, like streaming audio and video, images and text. Generally speaking, it enables simple authoring of interactive audiovisual presentations [MICHEL 2001]. With SMIL, other useful technologies have been born. It is the case of XHTML+SMIL, which includes a subset of the SMIL 2.0 specification, providing support for animation, content control, media objects, timing and synchronization, and transition effects, with XHTML and CSS features [NEWMAN 2001].

What we purpose in our environment is to use multimedia authoring tools that understand and produce SMIL and SMIL+XHTML documents. These documents could be linked in normal web documents, such as the documents created by Amaya, and presented by web browsers (like Microsoft Internet Explorer 5.5, that presents XHTML+SMIL2.0) or by its plug ins (like Real Player plug in, in Netscape browser, that presents SMIL1.0). As a consequence, users may add the results of these multimedia synchronization tools to the documents created by Amaya, and doing so, they may create rich hyperdocuments for their e-learning courses.

Multimedia environment

Figure 3 - Multimedia features

Figure 3 shows the interaction of the multimedia tools with the web server, presented in the previous section. The idea here is keep the produced multimedia resources and files in the same web server as the web pages. Thus, all the e-learning material will be available in just one server, and all authors involved in the authoring process will be able to access and use the available material and, mainly, collaborate over this. Therefore, the workflow element of the proposed environment, as we will see in Section 5, may help these authors in the multimedia authoring tasks by associating the necessary tools to every task, and also by telling the authors when those multimedia authoring tasks have their place in the course's production.

4 Cooperative features

When working in a group, we expect to develop products with better quality and productivity, through an harmonic and cooperative interaction among the group members [DIAS 97]. We expect to enhance the productivity in a group. So, in order to integrate this aspect in the e-learning authoring process, we provided some support for groups to cooperatively design and create e-leaning courses. Thus, it's possible to the authors to divide the process in small pieces, to enhance their productivity, to take profit of colleagues' expertise, and also to discuss, exchange ideas, etc. Finally, working in a group, authors may improve the e-learning authoring process, enrich the course's content and reach a better final product.

In the proposed environment, we chose not to adopt a complex groupware system, but only to use a few cooperative elements, indispensable for the success of the work. Thus, we chose to improve our tools with cooperative elements, like awareness and annotations, while we remain closer to simple applications design, working with open and worldwide known protocols and technologies. The cooperative elements used by us are presented below.

4.1 Awareness

As stated before, we believe that the work executed within a group produces better results through the harmonic interaction of the group members. To reach this harmonic interaction, the group members need to be aware of the colleagues' activities, because, according to Gutwin and Greenberg [GUTWIN 99], being aware to the colleagues and their activities is important to make the work natural and fluid.

This leads to the concept of awareness. Awareness is the knowledge on group activities, including past, presents and future activities. It's also the knowledge about the group itself and its overall status [KIRSCH 2001a]. It is the awareness support that makes possible to transform irregular interactions in consistent interactions through time, allowing that the members be kept updated on the important events for the group [DIAS 97], [ARAUJO 97].

So, to help a group of users to create an e-learning course, we decided to give them some support to awareness. To do so, we enriched the tools used in the proposed environment with a small, but useful, awareness support. This has been done by the addition of the framework BW and a small awareness protocol, based on a XML structure. The framework BW was designed to provide awareness support, especially in asynchronous environments (like the Web itself) [KIRSCH 2001b]. The awareness protocol created by us allows the exchange of awareness information between client tools and an awareness server. Combining these elements with the others authoring tools, the users could receive the notification of many events, like changes or annotations made on a document, or even perform queries to filter them.

As both, the framework BW and the awareness protocol, are open tools, the proposed environment still remains open, respecting our choice to produce an open environment.

4.2 Annotations

Annotations act as a communication resource. They allow the co-authors of a document to exchange experiences, opinions, comments, questions, etc, and to enrich the cooperation process. Annotations give to the group the possibility to asynchronously discuss about the work they are doing together, leading them to a better document.

We have chosen, for this annotations resource, to use W3C's Annotea. Annotea is a web-based shared annotation system based on general-purpose open RDF infrastructure, where annotations are modeled as a class of metadata [KAHAN 2001]. It treats annotations as external statements made by an author about a Web document. Annotea stores these annotations on central RDF bases, in one or more annotation servers.

As Amaya implements also an Annotea client, the users can easily use this resource without changing the application, doing theirs annotations directly over the documents they are constructing. By using annotations, these users may exchange ideas, comments, questions, finally, they may discuss about the documents and cooperate.

Moreover, the annotations form an important communication channel, not only among teachers during the authoring process, assisted by the proposed environment, but also between teachers and students reading the courses. The use of Annotea allows both, and this can be very useful for the course presentation, which is not addressed in this paper.

4.3 WebDAV

In Section 2, we proposed using Amaya to create and publish web pages in a well configured HTTP server. However, just this combination Amaya/HTTP doesn't cover the "lost update problem" (when a user's update is overwritten by another user's update). To treat this question, we introduce in the Amaya editor an Internet protocol designed for authoring purposes, the WebDAV. The WebDAV (WWW Distributed Authoring and Versoning ) is a set of extensions to the HTTP protocol which allows users to collaboratively edit and manage files on remote web servers [WEBDAV 2001]. It aims to extend the HTTP protocol to given place to an open architecture at protocol level, to develop new distributed authoring tools in the web, specially emphasizing the collaborative authoring of web pages [SALCEDO 98], [WEBDAV 99].

WebDAV defines operations over properties, collections, namespaces and overwriting protection, and for these operations, it defines new methods, headers, request and response entity bodies [GOLLAN 99]. Nevertheless, versioning features, present in the original proposition, have been moved to Delta-V IETF work group, which aims to extend WebDAV and HTTP/1.1 for those features [WHITEHEAD 99].

The "lost update problem" is a delicate question in cooperative environment, because important user's contributions may disappear. To prevent this problem in our environment, we introduced in Amaya a WebDAV support, which is able to interact with Apache HTTP server, that already deals with DAV requests, to prevent this problem.

Figure 4 presents the proposed environment for e-learning authoring after the aggregation of these cooperative features.

cooperative environment

Figure 4 - Cooperative features

5 Workflow

To organize the e-learning authoring process and to connect all the features presented in the sections before, we introduced in the proposed environment a workflow element - the authoring workflow. This workflow defines the tasks for the creation of the course and their coordination within the authoring group. It is a workflow to control the authoring process, designed to help professionals to create a course, to create e-learning material, and not to follow this material. This workflow does not control the presentation of the course, neither does it define the students' tasks. The presentation of the course is not our goal in this paper, and just some considerations about this are made in Section 6.

As stated before, the authoring workflow is defined by the coordinator of the group, taking in consideration (1) the members of the team, (2) the kind of e-learning course under construction, and (3) the standardization of the course development center. A basic authoring workflow was proposed in [SIZILIO 2000], and may be easily adapted for a specific course.

Our purpose is to introduce a workflow engine inside the server (the same server that includes HTTP and Annotea). This engine has an interface composed by CGIs and Servelets, that allows the environment tools, like web authoring tools, to interact with this engine and follow the authoring process. The workflow that describes the authoring process is expressed in a predetermined language, according to a XML DTD specially defined for this purpose. Using this workflow definition language, the group coordinator may express the necessaries tasks, resources and constrains for the creation of the course. He may define what task should be accomplished and when. He can also associate a tool to be used to accomplish a specific task, or even define what should be the resulting element for the course (for example, by defining the URI where the resulting resource should be published). Through this workflow description, the coordinator specifies the authoring process to be followed by the group. In order to help the coordinator, a graphic workflow editor was constructed, using the SVG facilities present in Amaya. Through this editor, the coordinator will be able to easily define the workflow. The editor itself will generate the XML description of the workflow.

The workflow description is submitted to the server, where the workflow engine is processed. By interpreting this workflow description in XML, the workflow engine will understand what tasks, resources and constrains the workflow has, and will be capable to control it. Besides this description, the workflow engine may use the awareness information to better control the authoring process. For example, the progress of a document could be seen through awareness events like "save document". These awareness information are maintained by the framework BW in a centralized database. This database could be periodically consulted by the workflow engine, and base some of its decisions on them.

On another hand, the author will be able to interact with the workflow engine by its CGIs interfaces. Using these interfaces, the users may request a task, following the workflow sequence and constrains, and also interactively supply information about the realization of the task to the workflow engine (for example, by clicking in a specific URL when the task is finished).

Figure 5 shows the complete environment proposed in this paper: a server, where all the server processes (the workflow engine, the HTTP and Annotea servers) and data (created pages, multimedia resources and awareness data) are placed, and clients using multimedia tools and the Amaya editor, enriched with awareness support.

The  complete environment

Figure 5 - The proposed environment

6 Future Considerations : Presenting the Course

In this paper, we have discussed only the e-learning authoring process, treated by the proposed environment. However, the authoring process is not the only process involved in e-learning. Complementing the authoring process, there is the execution process, where the created course is presented to the students. We did not address the execution process in the proposed environment, but some considerations about this should be done and shall be the target for future works.

The first point to remark is the need of an execution workflow to control the presentation of the course and the student's task. This execution workflow should define what tasks are mandatory, what tasks are optional, in what order the student should accomplish those tasks, etc. It should control execution of the course to guarantee that the course content (or its mandatory parties) will be correctly presented to the student.

In an ideal situation, this workflow should consider the student's characteristics, as nature (a mandatory student or a visitor) and level (a beginner, an intermediate or an advanced student) to take some decisions. Ideally, the course content should be adapted to the student according to his characteristics.

To reach this content adaptation, we could introduce negotiation services in the e-learning environment. These negotiation services would allow support to the diversity of students' characteristics, capabilities and preferences. The negotiation task aims to deliver a best content according to the client profile. This last can be declared efficiently in a RDF [LASSILA 99] or a CC/PP structure [W3C-CCPP 2001]. The client can negotiate courses' content to receive well adapted ones, respecting the user agent capabilities, the level and the nature of the e-learning desired (or needed) by the student.

Those client profiles may represent the students' preferences. They may address the student's nature. For example, if it's a mandatory student, which should be heavily controlled by the execution workflow and should be submitted to evaluation sections, or if is a visitor, free to navigate in the course content and without evaluation sections. These profiles may also indicate the student's level, his precedent courses, and other useful information that may help to define a course's better adapted content and navigation. Based on those profiles, the negotiation task can be applied on the fly, on the course's final content produced after the cooperation tasks of the authoring group. Thus, we may allow to a future student to exploit the environment and to use the understandable content according to his declared profile.

Since actual protocols, such as HTTP [IETF-HTTP 96] and TCN [TUE 98], are based on pure versioning selection mechanisms and lack for performed negotiation strategy, a perspective solution for these negotiation services is to use a proper negotiation layer as the one introduced in [LEMLOUMA 2001]. The use of a specific layer for negotiation services between the student and the execution workflow may also deal with "off-line" situation. When the student is disconnected from the network and still wants to follow the course during this period. Using this layer, it will be possible to negotiate with the workflow a content adapted to this off-line condition (and also to the student's preferences). It will be possible also to negotiate the synchronization between the tasks accomplished by the student during its off-line period and the workflow, just after the reestablishment of the student's connection.

Therefore, we should remark that if such negotiation services are used in the execution of the course, the authoring process will be affected. Authoring a negotiable content must be one of the major concern during the e-learning authoring step. Basic and required steps (such as the definition of content and courses profiles [LEMLOUMA 2001]) can be easily achieved since the proposed e-learning environment uses open models like XML and SMIL, which facilitate ensuring device independence principle.

7 Conclusions

The proposed environment is mainly based on open tools and standards. This characteristic makes this environment a cheap solution, applicable in almost any real world situation. For example, in under-development countries, low budget institutions may take profit from this environment to produce their own e-learning material. Besides this, the proposed environment is also a very modern one. We use many state-of-art protocols and technologies, like XML, used in Awareness Protocol, XHTML, MathML and SVG, used in the web pages created by Amaya, SMIL, used in multimedia tools, and WebDAV under Amaya. All these technologies lead the proposed environment to a comfortable position: it is modern, open, and the documents created using this authoring environment may be presented by many applications, in any platform.

The environment that we presented in this paper is an authoring environment, designed to support authors producing cooperatively e-learning materials. By using this environment, those authors may define and follow the authoring process, controlled by the workflow. This workflow and all tools associated, like Amaya, do not realize any kind of semantic control over the course content. That is, the content of the course produced with this environment is created and controlled only by the authors themselves. Despite of this, we believe that the work in a group, composed by educators and technical people, and the presence of a workflow describing the authoring process will help those authors to produce a better course content.

This environment is still construction in two sites, one in France, at the Opera research group (INRIA Rhône-Alpes), and another in Brazil, at the Sigha research group (UFRGS). We have in this environment some features in a more advanced stage, like the web authoring tools, and others just in the beginning, like WebDAV and workflow features. This later is a important piece of this environment and constitutes an innovation. We expect, by implementing this workflow, to enhance the e-learning authoring process, because the authors won't need to constantly deal with coordination tasks and they shall dedicate themselves completely to the authoring tasks.

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