 |
 |
 |
 |
 |
 |
 | |||
 |
 |
 |
 |
 |
|
|
|||
Contents
Challenges & Opportunities in extending Classroom and Campus : Columbia Borbely,E. VideoConferencing in a multicampus setting Purcell, P., & Parr, G. ISDN-based Videoconferencing in Australian tertiary education Latchem, C., Mitchell, J., Atkinson, R. ISDN Telephony in Norway Kristiansen, T. Videoconferencing for education and training Lange, J. A French Experiment in Distance learning by ISDN: 'Le Visiocentre de Formation' Lafon,J-L. ISDN Technology in Teaching Davis, N.
Columbia University runs a Video Conferencing link between remote sites, using digital US standard 56Kbit/s telephone lines. Sites are in the region of 120 miles (190 Km) apart. The hardware used here is not compatible with the BT desktop system: Columbia is using true Video Conferencing with a backup team of technicians controlling cameras, sound and lighting. However, some of the training problems they have experienced are similar to those expected of the desktop V.C. systems.
Training Difficulties Found:The University of Ulster has four campuses spread over the Province of Northern Ireland. For some time they have been using dedicated 2Mbit connections between their campuses for Video Conferencing. A new narrow band system was introduced in January of 1993, using BT's VC7000 ISDN video conferencing hardware ( The fore-runner of the VC8000 ).
Training Difficulties Found:For use with overhead projectors, cameras had to be focused rigidly on the screen for a considerable period of time in order to give the video compression system time to fully resolve the image. A considerable amount of time was needed for the transmission of overhead slide movements and other gestures by the lecturer. Added functionality came from projecting the VC7000 image using video projectors onto a 10x6 ft (3mx2m) Screen, and connecting the audio output to a public address system. A radio microphone was used to accept questions from the audience.
This chapter concludes that the success of the new system in being a useful medium for education rests more on user acceptance than on the technology itself. It cites the University's ongoing user appraisal studies of the hardware as a positive response to this need. However, there is little discussion in this paper of the actual problems involved with the system's implementation.
Over 70 sites currently use some kind of ISDN Video Conferencing in Australian tertiary education. Although originally most used 2Mbit/sec or 384Kb/sec links, the advantages of video compression have meant that 128Kbit/sec (ISDN-2) is becoming the standard due to its price/performance ratio.
Training Difficulties Found:Atkinson states that Video Conferencing's potential currently outweighs it's usage. Concludes that more research is needed into the instructional design and learning aspects of Video Conferencing. Acknowledges that it is easy to produce poor learning material with Video Conferencing. Insufficient research has been done to highlight the strengths and weaknesses of Video Conferencing with respect to other distance education media.
Norwegian Telecom Research have produced a desktop Video Conferencing platform which runs at 64-128Kbit/sec, and is similar in design and appearance to BT's VC7000 hardware. Their system is set up between campuses across Norway. Large projected screens were used in lecturing, with multiple microphone inputs for audio communication. Although the paper does not specifically detail training difficulties, some interesting points are raised.
Training Difficulties Found:Students need to be allowed period of time to adjust to having distance lectures. New presentation techniques must be developed due to the limitations and eccentricities of Video Conferencing. Training is needed to get teachers and pupils to exploit the technology,but this chapter does not attempt to address this need.
Lange claims Video Conferencing is different to past failed education revolutions because educators do not need to change their lecturing habits. This in itself is a contentious issue. This chapter advocates spending high to gain significant increases in profit, using an initial investment of £20,000 - £80,000 per video conferencing set-up. However, some points considered highlight problems with the ISDN systems.
Training Difficulties Found:Dynamic echo cancellation: major problems can occur with systems where the two systems can not accept synchronous input. In systems where there is an appreciable time delay (more than .5 of a second), a rehearsed protocol must be used to communicate on an interactive level. Remote camera control gives the lecturer more a concept of their audience when addressing just a screen. Multiple video and audio inputs allow for a greater feeling of "presence".
Use of large monitors and audio P.A. systems eliminated problems associated with sitting at the back of a lecture room. The monitor has the functionality of an overhead projector, but it is the only image that can be seen by the recipient students. Careful preparation of slides and documents is essential to keep the students' attention from wandering. Students have to be attentive to the monitor, as they cannot rely on the information being present for long periods of time - unlike a standard blackboard.
The Video Conferencing system acted to accentuate the normal lecture: a good lecture becomes better, yet a long boring lecture can seem much longer and more boring. The lecturer feels isolated from the class because of the lack of background audio "hum" that is present when actually in a lecture hall. The lecturers had to spend more time preparing material, having to plan timings of overheads and develop a "screenplay" for the lecture. Lecturers found it difficult not to talk through the entire lecture, feeling they had to fill in all silent gaps: a problem associated with inadequate communication feedback .
A maximum of one hour of lecturing was set. Every 20 minutes of lecturing, a pause was introduced for summarising and questions from the floor. This formalises the interaction within the lecture and leads to less spontaneity from both sides of the network.
The University of Exeter has networked links to several surrounding Secondary (12-18yrs) schools. The ISDN-2 links are used mainly for remote teaching, and have no Video communication. The system comprises of an audio telephone channel, and a shared computer desktop. A tutor can remotely control the student's desktop, thus demonstrating his or her expert knowledge on a personal level.
Training Difficulties Found:Long delays between voice and desktop manipulation was confusing, and meant a new protocol of communication had to be introduced. Delays meant the remote interaction took longer than a face to face communication session.
This article is somewhat dated. However, it does provide useful pointers on hosting video conferences:
Research based at the College of Education, Wyoming. Four school districts were involved in multi-site video conferencing, with the potential for increasing this number to a further 16 sites if successful. The subject matter consisted of a series of wide ranging lectures taught to 1st and 2nd year undergraduate students.
Training Difficulties Found:Bruce and Shade found that 16 students at four sites was a better configuration than 4 students at sixteen sites. In general, students to site ratios should be higher than sites to students.
This research has been carried out at Washington State University, using high bandwidth Microwave based video conferencing links. Although this system is different in many ways from ISDN based video conferencing, similar difficulties arose. The research centres on the use of video conferencing to teach course material over 4 separate campus sites. The staff teaching on the course were given various questionnaires in the hope of measuring the felt effectiveness and satisfaction of lecturing over the network.
Training Difficulties found - A problem with dialogue and interactivityIn general, the staff consulted were satisfied with the over all use of the system. The majority (66%) were satisfied that the system was at least no worse than a standard local lecture. However, the one area where the video conferencing failed to deliver was in how interactive their seminars were. Most staff felt less involved with remote students, and were unable to keep remote lectures from becoming cold or impersonal. The report recommends to increase the use interactivity between sites with more with more dialogue and use of mail/email facilities.
Multimedia Integrated Conferencing for European researchers. The MICE project is concerned primarily with using video conferencing through the MBONE conferencing system. This uses high bandwidth connections via the Internet to transmit video/data/audio information between many sites.
Training / Support concerns:From the MICE home page, it is possible to gain information on how to set-up and initialise the hardware and software necessary to use MBONE based video conferencing. Their tools page gives good hardware and software user guides. Other on line user documentation includes a page on getting started with video conferencing, detailing hardware, software, and physical requirements such as lighting, a step by step countdown list of tasks to perform before a video conferencing session, and their presentation hints page. Overall, these pages provide support for hardware and software installation, and some hints on presentations, although these do not go into specific details, and are certainly not exhaustive.
Using the MultiCasting backbone (MBONE), the Chicago conference on the World Wide Web was reached by over 400 remote viewers. In general, these remote users supported this initiative. However, many technical difficulties were experienced with this "multicast". The conference was set out as an experimental use of the (then) very new hardware, and this was stressed to the users at both the local and remote sites. An "Interlocutor" was present at the multicasting machine to co-ordinate responses from remote sites. During discussions, the interlocutor acted as an intermediary between the local site and the questions coming in from the network.
Training / Support concerns:Before the conference, information on limitations on MBONE conferencing, including the protocols for interaction and dialogue between remote and local sites, were made available on the Internet. This was done in the hope that this would diffuse some of the problems associated with the dialogue between sites.
One major problem with the multicast arose out of the low bandwidth of the Internet connection. The organisers stressed that this was due to a technical fault, and so should not be regarded as symptomatic of the MBONE system. Many remote viewers complained about the visibility of the video for presentations - presenters were not made familiar in advance to the use of colour in preparing slides for video captures. Many remote participants complained specifically about the use of pastel colours with grey backgrounds, and clashes of texts with backgrounds (for example, blue on white).
Technical support was only available over email or other networked services. Technicians should have been present to deal with the many problems which occurred. Ambient noise caused much interference with the conference, as no personal microphones or headsets were used. The workstation was placed on a standard Audio Visual cart, which meant it was difficult to type or use when technical difficulties arose.
The interlocutor was not able to adequately cope with using the software, controlling the remote interactions, and acting as the multicast host. More technicians should have been present and these tasks should have been performed separately.
Recommendations arising from the conference:A number of useful recommendations were suggested after the conference. Major fundamental recommendations were noted, such as having one multicasting unit for every room, (instead of moving the system around the conference halls), making sure rooms have adequate lighting, having rehearsals, notifying participants of any limitations or special considerations for presentations, and having technical support staff within easy reach. A remote user survey carried out after the conference highlighted the frustrations felt by users would could not see clearly due to poor lighting, camera movement, and poor resolution on distant camera shots, and could not hear properly due to background noise levels, and poor microphone positioning.
Contents
Graphics Multimedia Virtual Environments Visualisation Contents