The technology partners had to keep a series of important criteria at the back of their minds in defining and evaluating the different solutions. The list of user requirements was never far out of reach whereas the primary concern of the project is to facilitate access to the WebSET tools and content across the World Wide Web. Software functionality and performance should therefore be adapted to the specifications of the target computers at the end-user sites which consist of medical centres and high schools, only equipped with fairly modest computer hardware. As an average end-user machine, the WebSET consortium envisaged a PII 266 MHz, featured with a 2Mb Graphics card without any dedicated 3D hardware acceleration.
In addition to the Web-based WebSET version, the partners intend to design a standalone version which will be integrated into the existing framework of FrameSET, a container for medical simulation modules already used by the Royal College of Surgeons of England. For this laboratory-based solution, it is possible to re-use several tools from the Web-based, so-called e-commerce WebSET application, according to the partners. One of the major aims is to provide a cost-effective interactive 3D e-learning environment for knowledge delivery and skills training, which can be accessed by the trainees wherever and whenever they wish. This means that the WebSET partners have to take into account technical factors such as bandwidth limitation and user factors involving a minimum of prerequisite computer knowledge.
Since the existing Web-based distance learning infrastructure approaches like WebCT, Blackboard, and PlaceWare are considered being too costly, the WebSET technology assessment reporters prefer to develop an environment based on Extensible Mark-up Language (XML) technology and tailored to the needs of the project, including an integrated on-line tutorial. This tool will be augmented with Java applications, if this need occurs in particular learning content applications. The chosen file format to render multi-media files and 3D graphics is Virtual Reality Modelling Language (VRML) maintained by the Web3D consortium. Since the Manchester Visualization Centre, which is the co-ordinating partner for WebSET, has already created a set of simulators and training tools with VRML, it is only logical to continue the development task using the same Web3D technology.
The current standard is VRML97 but if appropriate, the WebSET team hopes to extend the VRML Scene Graph with the X3D version, its successor which is still underway. This X3D standard includes a subset of VRML97 features and is based on the XML file format. In addition, X3D also defines standard programming language interfaces to its functionality and has the promising potential to integrate with Document Object Model language interfaces. The X3D implementation, Shout3D, constitutes a commercial Java-based VRML rendering engine, developed by Shout Interactive. The WebSET partners are inclined to integrate this tool because it removes the need for a dedicated 3D plug-in, turning WebSET into an environment which is simple and intuitive in use.
Due to the fact that VRML forms more of a modelling specification instead of a real programming language, WebSET requires an additional technology to carry out the mathematics behind the simulation of physiological processes. The WebSET team prefers to use Java because of its strong relationship with VRML and its capacity to be implemented on the Web in applet form. Also, one should keep in mind that the Shout3D renderer is a Java applet-based engine. Another major challenge to be met by the WebSET consortium is the multi-user interaction. There are a lot of commercial collaboration tools on the market, including Blaxxun, Active Worlds, Helios, Holodesk, Community Place, and VNet. Nevertheless, WebSET partner uma Holding, together with Geometrek, developed DeepMatrix in a joint venture.
DeepMatrix has been adopted by WebSET for several good reasons. First of all, this Java-based solution is feature-rich, allowing users to be represented with a personal avatar. The 3D environment is divided into different rooms. Only users in the same room can communicate with each other via a simple text chat, offering public and private messages. Each room can be authored to use shared VRML events. DeepMatrix is also compatible with the Shout3D rendering engine. Support is available from within the project since uma has been involved in building the tool. The client is implemented as a Java applet and the server can be run on different platforms. Problems with firewalls are solved by allowing the single TCP port on the firewall to connect to the server and enter the multi-user system.
The use of a low-end haptic feedback tool is an optional but highly desirable feature for the WebSET project. The computer gaming scene might hold in store some cost-effective force-feedback devices, though the partners are well aware that this solution can never accurately represent the delicate tactile sensations of surgery. The only aim would be to enhance the visual cues by synchronised tactile effects, however crude they may be. In this regard, the partners have a slight preference for the Logitech Wingman Force-Feedback Mouse to optimise the simulation experience.
To document the XML-based infrastructure, WebSET has selected the Virtual Magazine Publisher (VMP), designed by project partner Genias Benelux. VMP constitutes a software system to manage XML-based magazines or manuals, providing interfaces for authoring and editing. The publishing module offers XSL-based publishing facilities. The authoring tool is available to the project partners. The WebSET partners have completed the technology assessment report with an overview of XML editors to allow customisation, responding to specific end-user needs; XML design tools and standard libraries; 2D toolkits and Web browsers for both custom and standard preview components; and content management systems to support distributed collaborative procedure authoring.
A special chapter in the report has been dedicated to the availability of meta-data standards as a resource for WebSET to discover applications and tools that might be useful to integrate. One of the project tasks for that matter is the draft of a taxonomy and meta-data specification. As such, the report is referring to the general-purpose Dublin Core Meta-data Standard; the IEEE Learning Technology Standards Committee (LTSC) Standards. The LTSC has a series of working groups in which the Learning Object Meta-data Working Group (LOM) is of particular interest to the project. The Prometeus initiative which stands for Promoting Multi-media access to Education and Training in the European Society constitutes a third source with a special interest group dedicated to Web-based Open and Distance Learning. More details about the WebSET user requirements are available in the article Defining user needs for on-line surgical simulation tools and multi-media learning content for physiology.