Acquiring Working Knowledge through Asynchronous Multimedia Conferencing
In recent years, education world-wide has been experiencing an unprecedented rate of change, forcing learning institutions to incorporate new teaching and learning methods and to enrich their learning environments with modern tools and services, in order to manage this change (Ford et al., 1996). New learning situations increasingly involve learners in collaborative distance learning: where learners’ individual efforts are focused on a joint, learning-related task and where their activity does not entail co-present or even synchronous interaction (Lim & Benbasat, 1991; Collis & Smith, 1997).
The widespread use of information and communication technologies (ICT), and particularly the use of the World Wide Web (WWW), has made feasible many new forms of collaborative distance learning activities, that take advantage of the capacity to integrate communications with information access and organisation, within a commonly accessible hyper-linked environment (Collis, 1999; Khan, 1997). There is an increasing amount of research supporting the critical influence that the choice of communication technology and the design of any instrumentation, used commonly by the learners, can have on both the process and the product of collaborative distance learning (Collis & Smith, 1997).
Asynchronous computer mediated conferencing and, especially, asynchronous text-based conferencing (ATC), has long been established as having value in supporting the collaborative distance learning process, because it offers flexibility in the use of time as well as space. However, this seems to be the case only when what is being learned is ‘textbook’ knowledge. Text has its virtues, but it is not sufficient for all purposes: more than ten years of experience with this approach reveals that it can be quite hard to begin and sustain a discussion about specific working practices if the medium of exchange has to be text. When it comes to the communication and learning of skills, especially the complex skills that are embedded in real-world working practices, the support offered by this kind of technology proves to be insufficient, in the sense that it makes only some forms of exchange about working practices feasible or straightforward.
Undoubtedly, it is nowadays of critical importance for our educational system to facilitate the acquisition of working skills that learners or practitioners can apply in their employment. Learning can be reconceptualised as a process of increasing mental, physical and organisational involvement in a community of practice: a process in which learners come to understand, adopt and eventually improve the actual working practices of experienced practitioners in their field (Singleton, 1998; Wenger, 1998). This view of how to help learners acquire applicable, contextualised, vocationally relevant knowledge makes the sharing of information about actual working practices a central problem.
We suggest that a solution to this problem might be the use of asynchronous multimedia conferencing (AMC). We believe that AMC can really help because it sustains most of the benefits of ATC, while at the same time it supports:
On this basis, our team at the Software Engineering Laboratory of the National Technical University of Athens (NTUA) has developed WebOrama, a Web-based system for ordered asynchronous multimedia annotations. WebOrama provides an integrated environment that enables learners, teachers and practitioners to collaborate in constructing a communal hypermedia resource whose content focuses on a set of real-world working practices. Both the process of constructing the resource and the end product itself are, we believe, important in promoting everyone’s learning. The main goal of WebOrama is to serve as an experimentation platform for understanding how well different components of AMC support different learning activities and how existing technology can be utilised and improved in order to help users of AMC derive greater benefits from their experience.
The WebOrama system is described thoroughly in this article, with emphasis on the system’s design and the implementation approach. Furthermore, some preliminary results, based on its initial use, are presented, followed by some considerations regarding future work.
Design issues for the WebOrama system
The WebOrama system has been developed in order to serve as an integrated environment that will facilitate the sharing of working practices and the acquisition of tacit knowledge embedded in these practices. In order to do so, it supports the incorporation of audio-visual representations of working practices created by more or less experienced practitioners, which then serve as base material for asynchronous, multimedia discussions within a community of practitioners or a class of learners (or even both). Furthermore, the system provides a means for exchange and review of the base material and the capture and hyper-linking of multimedia annotations to this material.
In particular, WebOrama’s usage facilitates the investigation of three main sets of activities:
In actuality, the second set of activities overlaps with aspects of the first. For example, some annotations will be in video format, which means that some of the issues involved in creating a video clip as a representation of practice will also be relevant to the creation of a video clip as an annotation. Furthermore, some annotations will themselves be representations of practice (‘That’s how you do it. Here’s how I do it’.)
In essence, the value of distinguishing between the three areas of activity lies in the emphasis on (i) creation of a multimedia object, (ii) annotation of a multimedia object (with a multimedia object), and (iii) reviewing multimedia annotations.
Implementation of the system
At a physical level, WebOrama is an entirely Web-based, distributed system that uses the client-server model (Sinha, 1992). Furthermore, as shown in Figure 1, its functionality can be logically divided according to the three-tier paradigm into three discrete tiers: the data tier, the application tier and the presentation tier. All of WebOrama’s components are implemented utilising the existing Web infrastructure and standards. The central component of WebOrama is a Web server that operates as a media server holding audio-visual representations of working practices. Multimedia annotations are stored as common hypermedia documents on the media server, with all the necessary meta-information embedded in an annotation server. Users of WebOrama have access to all of its functions through an ordinary Web browser, ensuring a standard and uniform user interface that facilitates both the creation and management of multimedia annotations, as well as the review of existing ones, in a productive and user-friendly way.
Figure 1. WebOrama' s three-tier architecture
One of the most innovative concepts of WebOrama is that of ordered annotations. This concept stems from the basic idea that the use of the system can be conceptualised as a stepwise process (Figure 2). At the first step, the creators of the audio-visual representation add annotations that further elaborate on their working practice, reflecting on their tacit knowledge. These annotations belong to the 1st order and are part of the representation of the working practice together with the audio-visual material. The 2nd order annotations are those made by other practitioners that, after reviewing the representation of their fellow’s working practice, will comment, argue, discuss, etc., either directly on a specific moment or period of the video-clip or on a 1st order annotation. Then the same base material can be used within a class of learners, in order to get insight in the represented working practice, as well as review the other practitioners’ annotations. The learners, of course, can themselves make comments, questions, etc., on this material, which all belong to the 3rd order of annotations.
Figure 2. Ordered annotations of WebOrama
In order to provide a clearer view of the WebOrama system, in the following paragraphs we discuss the client-server interaction and flow of control within a sample usage scenario. In this scenario a typical user, Foe, enters WebOrama, joins a class, views existing annotations and adds some new ones. Although this is only a subset of the functions supported by the system, it is quite complete for purposes of describing WebOrama’s functionality and look-and-feel (Figure 3).
Figure 3. WebOrama user interface
Entering the WebOrama system: When entering the system, our user, Foe, has to go through an authentication process. Her web-browser makes a request to the annotation server in order to retrieve the profile information for Foe. This information is essential, as it provides a way of filtering annotations to suit Foe’s specific needs and preferences.
Joining a class: The profile information also contains accessibility details, as each user is usually not permitted access to all available classes. Based on these details, Foe is presented with a list of the classes she can join. After joining a class, she is presented with a list of all available ‘topics of discussion’. Foe selects one topic and the browser proceeds with two requests: (i) the first, addressed to the media server, is for the audio-visual representation of a working practice that serves as the base of the specific discussion topic, and (ii) the second, addressed to the annotation server, is for the set of annotations within the specific topic. It is important to note that the browser uses the profile information, as well as the current selection of preferences that Foe has made (with the use of visual controls), in order to download only relevant annotations. Another important issue is that the browser proceeds with these two requests in parallel, in order to improve responsiveness.
Viewing annotations: Foe, while viewing the base material, has visual indications for existing annotations, which are highlighted according to the time-point of the base material that is currently playing. If Foe chooses to view an annotation, her browser makes a request to the media server using the HTTP protocol or streaming multimedia protocols, in order to fetch and display the content of the annotation (which might be in the form of another video-clip, an audio-clip or a text passage).
Adding annotations: While viewing the base material or an existing annotation, Foe can press a button in order to add a new annotation. Her action is captured by the browser and forwarded to the annotation server that records the specific focal anchor point at which the annotation is being made. Foe can then proceed with the addition of the (video, audio or textual) annotation, which is finally uploaded to the media server and appropriately hyperlinked to the rest of the annotations.
The WebOrama system has been used within the European Union's SHARP project, as a common infrastructure for “conducting user trials on capturing rich examples of working practices and on sharing these artefacts to scrutiny, debate and refinement within a community of geographically and temporally dispersed learners.” (SHARP team, 1996)
An example of such a use of WebOrama is within the undergraduate course “Introduction to Software Engineering”, offered by the NTUA. This use involves the augmentation of the conventional teaching approach, by ‘multimedia’ case studies that serve as a medium for the capture of real-world software systems user requirements. More specifically, the automation problem of a software system is presented through a comprehensive video clip, which is subsequently embedded in WebOrama, and annotated, if necessary, by the person playing the role of client for the software system. This material is then used as a kick-off for the discussion process through which the learners identify actual user requirements.
Another interesting use of WebOrama takes place at the Stord/Haugesund College in Norway. It involves the support of the “Introduction of ICT to teachers” training course. In this case WebOrama serves as an interactive learning tool that is combined with traditional classroom teaching. The course includes topics such as how to use a computer, the Internet and standard software. Being a basic level course, where trainees have little experience in the field, it is often difficult to explain textually how different actions can be carried out. Therefore, small video clips are produced, showing how these actions can be carried out. WebOrama is used to organise these video clips with annotations and to enable trainees to make their own remarks. It is interesting that the use of WebOrama has proven quite important, since the video clips along with their annotations serve as an additional learning resource that can be readily available, according to the trainees’ needs, so as to increase their understanding of the curriculum. More specifically, the WebOrama system helps in the automation of part of the teacher's work, the integration of some of the interactions in the classroom into an Internet-based learning environment, and the increase of interactivity between students and the learning material.
Using the WebOrama system for annotating a source video clip has proven efficient for supporting a discussion on the representation of practice presented in that clip. However, an issue that needs to be resolved is that of adequate scalability, especially with regard to the number of users, as well as user-groups, that WebOrama is able to support. Linked to this issue is the ability of the system to present only the information relevant to each user. This is particularly critical in situations where the user-base grows very large or different user-groups have simultaneous access to the same base material. In order to face this issue, we have been designing an algorithm for dynamic filtering of annotations that provides an adaptive and customisable representation of content, personalised for a particular user-group’s perspective.
Future plans towards additional improvement include the integration of a structuring mechanism that will enhance tracking of threads of discussion, as well as the packaging of the system in order to allow for large-scale deployment.
Though still a prototype implementation, WebOrama is already providing an invaluable experimentation platform, for the evaluation of the pedagogical effectiveness of AMC for the sharing of working practices within a community of practitioners and learners. Even though there are not adequate results yet for attempting a full-scale evaluation based on quantitative analysis, user observation, interviews and qualitative analysis have provided interesting findings and useful insights into learners’ needs. Based on these findings, we can better decide how well different components of AMC support different learning activities; suggest how technology might be improved towards this goal, and identify guidelines and protocols, which will help users of AMC derive greater benefits from their experience. (SHARP team, 1999).