CNETDP. 27 (6) 727-1110 (1995)
`
`ISSN 0169~7552
`
`and
`ISDN SV.
`
`MS '
`
`Volume 27 (199p)
`Number 6
`April 1'995
`
`Proceedings of the Third International
`World-Wide Web Conference
`Gt1est Editor:
`D. Kmemker
`URIL: http://www.elsevier.nl/ ·
`
`Page 1 of 13
`
`

`

`and
`ISDN SYSTEMS
`
`The International Journal of Computer
`and Telecommunications Networking
`
`Proceedings of the Third International
`World-Wide Web Conference
`10-14 April, 1995, Darmstadt, Germany
`
`D. Kroemker
`IGD-FHG, Darmstadt, Germany
`
`Th is issue is online available via URL:
`http://www.elsevier.nl/
`To access, use the password: els4www3
`
`ELSEVIER
`Amsterdam - Lausanne - New York- Oxford - Shannon - Tokyo
`
`Page 2 of 13
`
`

`

`COMPUTER NETWORKS
`and ISDN SYSTEMS
`
`The International Journal of Computer and Telecommunications
`Networking
`
`scope
`GOM PUTER NETWORKS and ISDN SYSTEMS is an
`international journal providing a publication vehicle for
`complete coverage of all topics of interest to those
`involved in the area. The audience includes man(cid:173)
`agers and operators of networks as well as designers
`?nd implementors in addition to regulatory lawyers,
`economists, policy analysts, and sociologists special(cid:173)
`U ng in the area. The Editorial Board will consider for
`publication any material that is of interest to these
`yroups.
`~ u bject coverage
`Material on all aspects of the design, implementation,
`.Jse and management of computer and telecommuni(cid:173)
`cation networks, communication sub-systems, and
`integrated services digital networks. Specifically
`included are non-technical topics such as economics,
`legal and regulatory issues, and social impact.
`fypes of contributions considered
`The primary purpose of the journal is to publish com(cid:173)
`plete papers covering a specific topic or project in suf(cid:173)
`ficient detail and depth to be of practical use to inter(cid:173)
`ested readers. In addition to full-length papers, short
`notes reporting on a small project or giving an interim
`report on a project will also be considered . The jour(cid:173)
`nal is meant to be a complete source of information
`on all aspects of computer and telecommunication
`networks and will also include news items and adver(cid:173)
`tisements in addition to the regular contributions dis(cid:173)
`cu ssed above.
`Submission of material
`It is preferred that complete manuscripts be submitted
`to one of the Editors, mentioned in the masthead (on
`the first inside cover page of this issue).
`Review procedure
`All papers and short notes are submitted to expert ref(cid:173)
`erees for review. Their reports are fully considered by
`the Editorial Board in selecting material for publica(cid:173)
`tion. The names of specific referees are never
`divulged to the author; however, some of the review
`comments may be provided to assist the author in
`revising his paper. Letters are reviewed by an Editor
`for appropriateness and content. If it is necessary to
`shorten or otherwise edit material submitted, this fact
`will clearly be indicated in the published form.
`Author's benefits
`1. 50 offprints of each contribution free of charge.
`2. 30%. discount on all Elsevier Science books (order
`forms will be sent together with the proofs).
`Subscription information
`Computer Networks and ISDN Systems (ISSN 0169-7552).
`For 1995 volume 27 is scheduled for publication. A com(cid:173)
`ISDN
`bined subscription
`to Computer Networks and
`
`Systems and Computer Networks for Research in Europe
`(supplement to volume 27) (4 issues) at reduced rate is
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`1995, Elsevier Science B.V.
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`No part of this publication may be reproduced, stored in a retrieval
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`
`Page 3 of 13
`
`

`

`Contents
`
`Editorial
`
`Living Documents
`J.E. Pitkow and R.K Jones
`Towards an intelligent publishing environment
`
`M. Roscheisen, C. Mogensen and T. Winograd
`Beyond browsing: shared comments, SOAPs, trails, and on-line communi-
`ties
`
`727
`
`729
`
`739
`
`K Kaarela, J. Oksanen and J. Takala
`An information model as a basis for hypermedia-based plant documenta-
`tion
`
`751
`
`Enhancements to the Lower Level WWW Protocols
`S. Lewontin
`The DCE Web toolkit: enhancing WWW protocols with lower-layer services 765
`
`K.E. Rowe and C.K. Nicholas
`Reliability of WWW name servers
`
`J.E. Donnelley
`WWW media distribution via Hopwise Reliable Multicast
`
`Applications
`M. Baentsch, G. Molter and P. Sturm
`WebMake: Integrating distributed software development in a structure-en-
`hanced Web
`
`773
`
`781
`
`789
`
`G.J. Mathews and S.S. Towheed
`NSSDC OMNIWeb: The first space physics WWW-based data browsing
`and retrieval system
`
`801
`
`J.E. Pitkow and M.M. Recker
`Using the Web as a survey tool: results from the second WWW user survey 809
`
`Authoring Environments
`K Weber
`Chapter 6, in which Pooh proposes improvements to Web authoring tools,
`having seen said tools for the Unix platform
`
`V. Quint, C. Raisin and I. Vatton
`A structured authoring environment for the World-Wide Web
`
`823
`
`831
`
`Page 4 of 13
`
`

`

`J. Paoli
`Cooperative work on the network: edit the WWW!
`
`84 1
`
`K.J. Maly, H. Abde/-Wahab, R. Mukkamala, A. Gupta, A. Prabhu, H. Syed
`and C. S. Vemuru
`Mosaic + XTV = CoReview
`
`849
`
`R. Peters and C. Neuss
`CrystalWeb - A distributed authoring environment for the World-Wide Web 861
`
`Training and Teaching on the Web
`B. Ibrahim and S.D. Franklin
`Advanced educational uses of the World-Wide Web
`
`D. Nicol, C. Smeaton and A.F. Slater
`Footsteps : Trail-blazing the Web
`
`J.K. Campbell, S. Hurley, S.B. Jones and N.M. Stephens
`Constructing educational courseware using NCSA Mosaic and
`World-Wide Web
`
`the
`
`D. Dwyer, K. Barbieri and H.M. Doerr
`Creating a virtual classroom for interactive education on the Web
`
`E. Bilotta, M. Fiorito, D. lovane and P. Pantano
`An educational environment using WWW
`
`Tools for Developing Web Services
`D. LaLiberte and A. Braverman
`A protocol for scalable group and public annotations
`
`K. Andrews, F. Kappe and H. Maurer
`Serving information to the Web with Hyper-G
`
`L. Perrochon and R. Fischer
`IDLE: Unified W3-access to interactive information servers
`
`Resource Discovery and Retrieval
`L. Shklar, K. Shah and C. Basu
`Putting legacy data on the Web: a repository definition language
`
`M.A. Sheldon, A. Duda, R. Weiss and D.K. Gifford
`Discover: a resource discovery system based on content routing
`
`C. Neuss and R. E. Kent
`Conceptual analysis of resource meta-information
`
`871
`
`879
`
`887
`
`897
`
`905
`
`911
`
`919
`
`927
`
`939
`
`953
`
`973
`
`Page 5 of 13
`
`

`

`0. Vizine-Goetz, J. Godby and M. Bendig
`Spectrum: a Web-based tool for describing electronic resources
`
`985
`
`C. Dodge, B. Marx and H. Pfeiffenberger
`Web cataloguing through cache exploitation and steps toward consistency
`1oro
`m~~eMn~
`
`S.A. Dobson and V.A. Burrill
`Lightweight databases
`
`A. Clausnitzer, P. Vogel and S. Wiesener
`A WWW interface to the OMNIS / Myriad literature retrieval engine
`
`1009
`
`1017
`
`U. Pfeifer, N. Fuhr and T. Huynh
`Searching structured documents with the enhanced retrieval functionality
`of freeWAIS-sf and SF gate
`
`1027
`
`Intellectual Property and Security
`T. Norderhaug and J.M. Oberding
`Designing a web of intellectual property
`
`1037
`
`S. Anderson and R. Garvin
`Sessioneer: flexible session level authentication with off the shelf servers
`and clients
`
`1047
`
`J. Kahan
`A capability-based authorization model for the World-Wide Web
`
`Tools for Analyzing WWW Use
`L.D. Catledge and J.E. Pitkow
`Characterizing browsing strategies in the World-Wide Web
`
`S. Mukherjea and J.D. Foley
`Visualizing the World-Wide Web with the Navigational View Builder
`
`D. Beckett
`Combined log system
`
`M.H. Brown and R.A. Shi/Iner
`DeckScape: an experimental Web browser
`
`M. van Doorn and A. Eliens
`Integrating applications and the World-Wide Web
`
`1055
`
`1065
`
`1075
`
`1089
`
`1097
`
`1105
`
`Page 6 of 13
`
`

`

`This material may be protected by Copyright law (Title 17 U.S. Code)
`
`Computer Networks and ISDN Systems 27 (1995) 879- 885
`
`COMPUTER
`NETWORKS
`and
`ISDN SYSTEMS
`
`Footsteps: Trail-blazing the Web
`
`David Nicol a,i, Cal um Smeaton b,
`
`2
`
`, Alan Falconer Slater b,
`
`3
`
`a Signal Processing Division, University of Strathclyde, Glasgow, UK
`b Department of Co111puti11g a11d Electrical Engineering, Heriot-Watt University, Edi11burgh, UK
`
`Abstract
`
`The World-Wide Web has already been demonstrated to be an excellent mechanism for the distribution of educational
`resources. However, current browsers do not provide much support for users navigating the Web. This is particularly true in
`cases where users follow a link from a previously prepared "trail" and then experience difficulties in returning to the point
`where they left. This paper describes a guided tour mechanism, known as Footsteps, which has been developed in an attempt
`to solve this problem.
`
`Keywords: Authoring environments; Computer based training and teaching; Tools and browsers; CGI-SCRIPTS
`
`1. Introduction
`
`Project INTERACT [9] has attempted to develop
`a generic framework for the use of simulations in an
`educational environment. A key feature of the ap(cid:173)
`proach taken by INTERACT is that simulations,
`which are constructed to be as pedagogically neutral
`as possible, are specialised for a particular session by
`embedding them within a hypermedia environment
`which provides supporting explanatory courseware.
`This hypermedia environment is supplied by stan(cid:173)
`dard W3 [1,6] tools, with the links between these
`tools and simulations being provided by the Interact
`Communication Facility (ICF) [10]. The complete
`environment, which includes an object-oriented sim-
`
`ulation toolkit with W3-based control and reporting
`facilities, is described in [11].
`The production of good educational simulations is
`a costly undertaking, typically requiring at least one
`person-year. To justify the construction of such pro(cid:173)
`grams it is necessary to be able to use each simula(cid:173)
`tion in as many circumstances as possible and within
`courses produced by different teachers. In a similar
`fashion, the components of the associated course(cid:173)
`ware should also be as reusable as possible. Al(cid:173)
`though the Web provides a superb basis for the
`development of distributed educational resources,
`navigation through the resulting structure can be
`confusing. Although it is arguable that such free
`exploration should be encouraged, we feel that the
`
`1 d.nicol@strath.ac.uk.uk; http:/ /www.eee.strath.ac.uk/ ~ nicoljdavid.html
`2 calum@cee.hw.ac.uk; http:/ /viper.cee.hw.ac.uk/ ~ calum
`3 afs@cee.hw.ac.uk; http: / /viper.cee.hw.ac.uk/ ~ afs
`
`0169-7552/95/$09.50 1995 Elsevier Science B.V.
`SSD! 0169- 7552(95)00016-X
`
`Page 7 of 13
`
`

`

`880
`
`D. Nicol et al./ Computer Networks and ISDN Systems 27 (1995) 879-885
`
`pragmatic constraints often placed upon students re(cid:173)
`quires that additional navigational aids be provided.
`These constraints are especially obvious where sys(cid:173)
`tems are being used to augment traditional laboratory
`work on science or engineering courses.
`The fact that students quite often have specific
`educational objectives for a particular session can
`therefore be seen to conflict with the possibilities for
`open-ended exploration presented by
`the Web.
`Novice users often feel lost in the information spaces,
`unsure of where they are, ''there is a risk that they
`will become disoriented or have trouble finding the
`information they need" [7]. Even in a small docu(cid:173)
`ment which could be read in one hour,
`''users
`experienced the ' lost in hyperspace' phenomenon' '
`[8].
`A simple solution to this problem is to construct
`courseware modules which are relatively self-con(cid:173)
`tained with few opportunities provided for explo(cid:173)
`ration. This type of courseware has already been
`used successfully with students at the three universi(cid:173)
`ties involved in INTERACT. Unfortunately, this ap(cid:173)
`proach can be seen to be somewhat at odds with the
`general "spirit" of the Web.
`Navigational aids within documents have been
`observed to be a cause of many navigational prob(cid:173)
`lems. Attractive navigation icons are often included
`within documents, with buttons such as "Forward",
`" Back" and " Up". These are almost inevitably
`hard-wired links to specific documents. These types
`of buttons are, of course, rather difficult to provide
`in documents (such as glossaries) which will be
`linked to by many URLs. This problem is com(cid:173)
`pounded by the inconsistencies between the naviga(cid:173)
`tional controls provided by browsers and those in(cid:173)
`cluded within documents. Assuming non-linear navi(cid:173)
`gation through a document, it is almost always the
`case that the result of selecting a ''Back'' link in a
`document will differ from the, apparently equivalent,
`button on the browser.
`To fully exploit the Web as a vehicle for the
`delivery of courseware a more supportive learning
`environment is required which can still make use of
`all the power of the Web whilst still maintaining a
`level of control over navigation. We must provide a
`navigational mechanism that allows students to fol(cid:173)
`low interesting links to resources anywhere on the
`Web whilst providing a simple means of returning to
`
`the point where the student left the set of materials
`which have been designated as being directly associ(cid:173)
`ated with the current educational objective.
`
`2. Guided tours
`
`In other hypertext systems guided tour facilities,
`such guided tours [12) and trails [2], have been
`employed to aid novice users navigate through infor(cid:173)
`mation spaces. Indexed overview facilities are also
`often employed [7].
`Guided tours can help to remove the dependency
`on navigating through a complex structure of hyper(cid:173)
`text nodes, and '' can be used to introduce new
`readers to the general concept of a hypertext'' [7].
`Figure 1 shows a conceptual diagram of navigating
`through a set of pages using a guided tour, with
`added functionality to manage any digression from
`the tour.
`INTERACT has developed a guided tour system
`for the Web, called Footsteps, which is intended for
`use with simulation-based courseware. Authors can
`set a pre-defined path for users to navigate through
`the courseware, with students being allowed digres(cid:173)
`sions from this pre-defined path whilst being pro(cid:173)
`vided with a "Return to tour" button on all docu-
`
`Document in T 01Jr
`
`Document outside of tour
`
`lir1k
`Norm.al hypert.€-:it
`Link bet•,•eien dc•o1Jrnent.s in t•:iur usinq
`n.a•,iig.atic•n butto::1n:;
`-
`
`F:eturn link to tour using "R'"turn t.o Tour" button
`
`Fig. 1. Diagram of tour.
`
`Page 8 of 13
`
`

`

`D. Nicol et al./ Computer Networks and !SDN Systems 27 (1995) 879-885
`
`881
`
`Fig. 2. Example of first page.
`
`ments not included in the tour, regardless of the
`source of these documents. An information bar is
`added to each document which contains the current
`location within the tour and links for following the
`tour.
`Figure 2 shows a typical page from a Footsteps
`tour, this example is a tutorial document used along(cid:173)
`side an external soil mechanics simulation. The user
`is free to click on any link on the page, if this takes
`them to a page outside the tour then this new page
`
`Fig. 3. Example of digression.
`
`Fig. 4. Example of index.
`
`will be modified "on the fly" to include a link back
`to the most recently accessed tour page. The user is
`able to travel as far as she wants from the tour with
`the security of always having available a direct
`means of returning to the appropriate step in the tour.
`An example of what happens if the user digresses
`from a tour is shown in Fig. 3; in this case the user
`has selected the help tutorial.
`An index button is also supplied on all pages on
`the tour, this allows users to examine the overall
`structure of the tour upon which they have em(cid:173)
`barked. The index page provides links to all the
`pages on the tour. A sample index page is shown in
`Fig. 4.
`
`3. Implementation
`
`Footsteps is implemented as a single perl CGI
`script [5,13], using libwww-perl [3]. The script reads
`a tour file, which specifies the URLs in the order
`they are to appear in the tour. Additional configura(cid:173)
`tion parameters can also be specified within the this
`file . An example tour file is shown below:
`
`BUTTON LOCATION
`top
`PREVIOUS ICON
`http: I /www.eee.strath.ac.uk/ images I
`
`Page 9 of 13
`
`

`

`882
`
`D. Nicol et al./ Computer NeMorks and ISDN Systems 27 (1995) 879-885
`
`previous.gif
`NEXT ICON
`http: I /www.eee.strath.ac.uk / images I
`next.gif
`INDEX ICON
`http: I /www.eee.strath.ac .uk/ images I
`index.gif
`USE DESCRIPTION
`no
`START TOUR
`http: I /www.eee.strath.ac.uk/
`http: I /www.eee.strath.ac.uk/ ~ nicol I
`david.html
`http: I /www.cee.hw.ac.uk/
`http:./ /www.cee.hw.ac.uk / ~cal um/
`cal um.html
`END TOUR
`When the tour starts, the Footsteps script re(cid:173)
`trieves the first URL in the tour file, but before
`returning it to the client it performs the following
`actions:
`Adds the information bar, with the current index
`in the tour and a set of navigation buttons;
`Parses the HTML and makes all link anchors and
`inline objects absolute references;
`Parses the HTML looking for Anchor tags and
`redirects all anchors back to the footsteps script
`with the original URL from the anchor as a
`parameter to the script;
`• Hidden form fields are used within the HTML
`returned to the client to store the current page
`number between documents. This means that no
`state information needs to be stored by the W3
`server.
`Figure 5 shows how the script sits between the
`user 's client and the servers which provides the
`documents on the tour.
`
`4. Navigation tool configuration
`
`The script currently provides the following tour
`configuration options:
`The navigation bar can be at the top or bottom of
`the page;
`A description field can be included alongside the
`"Next" and "Previous" icons, describing the
`pages to which these buttons link;
`
`__ ,,
`' /\ 4 ,,,:.;: .......
`
`Server
`\
`
`Server
`Ii
`
`_::rver
`
`Server
`"?"-....... •. , __ ·---....\'-...
`
`'~-- -.
`
`·-
`
`...:t.. --... ... ......_
`··-
`..
`~ ..:·::: ~ ... ">?>.
`... _ ...
`
`I
`..,.. .....
`,•
`....... ____ ,,.---
`I
`~
`I'< ~
`~j
`Fool.steps
`")<::. ~ ....
`
`-.. -
`-
`
`E:o(,,blioh P,q<
`Rt.:tri•:::v~ P:.iq·.::
`Dim\ LIRL;
`F:r::t•Jrrr P~9.:: to Cli!'.:nt
`
`Fig. 5. General overview.
`
`The images to use as the icons can be specified as
`URLs.
`
`5. Advantages
`
`Hammond and Allinson [ 4] report an increase in
`the effectiveness of hypertext in a learning environ(cid:173)
`ment when users are given ''useful tools embedded
`within a simple inte1face, in the hope that the worst
`consequences of task dependency will be absorbed
`by the strategic options that the range of facilities
`makes available to the user". Neilson [7] adds a
`'' wider coverage of the materials and more efficient
`access to new information'', when users are provided
`with guided tour and index overview features to
`foster exploration.
`The advantages of Footsteps are listed below:
`Users are allowed to follow a linear path through
`a large information space, but they are still al(cid:173)
`lowed to digress from the tour to explore other
`information sources with the ability to easily re(cid:173)
`turn back to the tour;
`Tour overviews, in the form of the index docu(cid:173)
`ment, provide extra navigational facilities;
`
`Page 10 of 13
`
`

`

`D. Nicol et al./ Computer Networks and ISDN Systems 27 (1995) 879-885
`
`883
`
`By using Footsteps, documents can
`remain
`reusable resources and be used in more than one
`tour as tour information is held independently of
`these resources;
`Using such a script, implementing meta-informa(cid:173)
`tion such as glossaries is simplified;
`Any document on the Web can be included in a
`tour;
`The Footsteps script can be used by a client
`anywhere on the Web, therefore the user does not
`have to be using the same local file system as the
`Footsteps script.
`The script does not require any modification to
`either the server or the client.
`
`6. Disadvantages
`
`The whole concept of guided tours actually de(cid:173)
`feats the beauty of hypertext, in that it brings
`back an emphasis on linear "page turning" rather
`than the free exploration of large information
`spaces.
`Twice the network traffic is created for the main
`text as all but inlined objects are retrieved in a
`two-stage process.
`Construction of the index document requires the
`retrieval of all pages in the tour, in order to
`extract their and (TITLE) ... (/TITLE) fields.
`This can take a considerable amount of time and
`may be wasteful if these pages are never visited.
`
`the Institute of Computer Based Learning 4 at
`Heriot-Watt University. The soil mechanics labora(cid:173)
`tory tutorial/simulation will be in use next term.
`The script has also been used for providing tours
`from home pages, such as the Project INTERACT
`Home Page [9].
`
`8. Future developments
`
`At the moment tour creation requires the genera(cid:173)
`tion of a tour file using any standard editor. We are
`at the moment carrying out requirements capture
`with a view to developing a WYSIWYG towMan(cid:173)
`ager editor. Once Web pages are written we envis(cid:173)
`age a situation not unlike Bush's vision where "a
`user might want to photog1'aph a whole trail for
`friends to put on their M emexes " , where trails can
`be created for others to follow [2]. These tours
`should be distributed on the Web like any other
`resource.
`At the moment the index overview facility is
`comprised of a list of pages on the tour, with the
`description of
`the page
`taken
`from
`the
`(TITLE) .. . (/TITLE) field of each document. We
`would like to develop this facility to include an
`optional graphical overview map of the tour. The
`script is also being extended to allow an extra de(cid:173)
`scription field to be specified in the tour file, and if
`present this will be used in the index, rather than
`having to retrieve the whole document just to re(cid:173)
`trieve this information.
`
`7. Experience
`
`The Footsteps script has so far been used in two
`sets of courseware. These are, a Web document
`aimed at teaching Fourier Analysis, and a tutorial
`document used in conjunction with an application
`simulating a soil mechanics laboratory/ experiment.
`The Fourier Analysis document is currently being
`used by students at the University of Strathclyde.
`Evaluation studies are currently being carried out by
`
`9. Summary
`
`This paper describes one solution to a naviga(cid:173)
`tional problem discovered during the construction of
`Web based educational resources. This solution uses
`a script to manage a tour through a set of documents
`on the Web, when users digress from this tour they
`are provided with a direct means of returning to the
`point where they left the tour. Tours in Footsteps are
`
`4 http:/ /www.icbl.hw.ac.uk
`5 http:/ /www.eee.strath.ac.uk/ ~ nicol/footsteps/footsteps.html
`
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`D. Nicol et al. / Computer Networks and ISDN Systems 27 (1995) 879- 885
`
`specified independently of the documents held within
`the tour, which allows a single document to be
`included in many tours.
`The latest version of the script is available at:
`http:// www.eee.strath.ac.uk / ~ nicol /footsteps
`/footsteps.html 5
`
`References
`
`[1] Berners-Lee, T. , World Wide Web Initiative . WWW Home
`Page: http://info.cern.ch/ hypertext/ WWW/ The(cid:173)
`Project.html 6
`[2] Bush, V., (1967), Memex revisited. In Bush, V. (Ed.) (1967),
`Science is not Enough, William Morrow and Co. Reprinted
`in Nyce, J.M., and Kahn, P. (Eds.) (1991), From to Hyper(cid:173)
`text: Vanna uar Bush and the Mind 's Machine. Academic
`Press, 197-216.
`[3] Fielding, R., (1994), libwww-perl, http:/ /www.ics.uci.edu
`/WebSoft/libwww-perlj 7
`[4] Hammond, N. and Allinson, L. (1989), Extending hypertext
`for learning: An investigation of access and guidance tools.
`in Sutcliffe, A. and Macaulay, L. , (Eds.), People and Com(cid:173)
`puters V, Cambridge University Press, 293-304.
`[5] McCool, R., (1993), The Common Gateway Inte1face.
`http:/ /hoohoo.ncsa.uiuc.edu/cgij 8
`[6] NCSA Mosaic Project (1994), NCSA Mosaic Home Page,
`http://www.ncsa.uiuc.edu/SDG /Software /Mosaic/NC
`SAMosaicHome.html 9
`[7] Nielsen J., (1990), Hypertext and Hypermedia. Academic
`Press Ltd.
`[8] Nielsen, J. and Lyngbaek, U., (1990), Two field studies of
`hypermedia usability. In McAleese, R. and Green, C. (Eds.)
`Hypertext: State of the Art, Ablex, 64-72.
`INTERACT, Project INTERACT Home Page,
`[9] Project
`http:/ /medusa.eng.cam.ac.uk/interact/ 10
`(10] Slater, A.F., (1994), The Interact Communication Facility.
`Proceedings of the First International Conference on the
`World-Wide Web, CERN Geneva, Switzerland. http://
`neptune.cee.hw.ac.uk/ - afs/www94/www94.html 11
`[11] Smeaton, C. and Slater, A.F., (1994), Integrating Simulations
`
`and W3 Courseware. Proceedings of the Second Interna(cid:173)
`the World-Wide Web, Chicago .
`tional Conference on
`http://www.ncsa.uiuc.edu/SDG /IT94 /Proceedings/Ed
`uc/ smeaton/ise _ www /ise _ www94.html 12
`[12] Trigg, R.H., (1988), Guided tours and tabletops: Tools for
`communicating in a hypertext environment. ACM Trans.
`Office Information Systems 6, 4 (October), 398-414.
`[13] Wall, L. and Schwartz, R.L., (1990), Programming per/,
`O'Reilly and Associates, Sebastapol, CA. http:/ /www.
`cis.ufl.edu/perlj 13
`
`David Nicol is a Teaching Assistant at
`the University of Strathclyde, currently
`employed on the TLTP Project INTER(cid:173)
`ACT, developing engineering simulation
`GUis. He is also the Signal Processing
`Division Web man ager, and SPD
`MBONE facilities maintainer. The au(cid:173)
`thor holds the Msc in HCI from Heriot(cid:173)
`Watt University, during which time he
`carried out research into physical activ-
`ity instruction via computers, and devel(cid:173)
`oped a prototype package to teach Yoga
`postures. He also spent a short period in Ultrix and PC support.
`The author is currently continuing requirements capture and
`design of educational W3 authoring support tools.
`
`Calum Smeaton is a Computer Assis(cid:173)
`tant at Heriot-Watt University working
`on the TLTP Project INTERACT, he is
`responsible for the design and imple(cid:173)
`mentation of the project 's software tool
`the Presentation Manager. After study(cid:173)
`ing Electronics and then Software Engi(cid:173)
`neering, the author spent two and half
`years at Marconi Simulation where he
`worked on systems and graphics soft-
`ware on their own proprietary hardware
`and compilers. He worked on several
`large projects for industri al simulators where he was responsible
`for all aspects of GUI' s.
`He has recently set up a W3 consultancy company called
`Orbital Technologies with fellow author Alan Slater.
`
`6 http:/ / info.cern.ch/hypertext/WWW / TheProject.html
`7 http :/ /www.ics. uci.edu / WebSoft/ libwww-perl/
`8 http: / /hoohoo.ncsa.uiuc.edu/ cgij
`9 http:/ /www.ncsa.uiuc.edu/ SDG / Software/Mosaic/ NCSAMosaicHome.html
`10 http:/ / medusa.eng.cam.ac.uk/ interact/
`11 http://neptune.cee.hw.ac.uk/- afs/www94/ www94.htm1
`11 http://www.ncsa.uiuc.edu/SDG/IT94/Proceedings/Educ/smeaton/ise_www/ise_www94.html
`13 http:/ /www.cis.ufl.edu/ perl/
`
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`
`885
`
`Alan Falconer Slater is a Research As(cid:173)
`sociate in the Department of Computing
`and Electrical Engineering at Edin(cid:173)
`burgh's Heriot-Watt University. He is
`currently employed on the SERC/DTI
`MOBIT project which is developing in(cid:173)
`dustrial Intelligent Training Systems in
`collaboration with a number of indus(cid:173)
`trial partners. Alan has also worked on a
`number of large European projects,
`funded under the CECJEs ESPRIT pro(cid:173)
`gramme, investigating model-based di(cid:173)
`agnosis and ITSs.
`
`During work on the INTERACT TLTP project, which aimed to
`produce an environment for delivering educational simulations, he
`became interested in hypermedia tools and the W3. He is currently
`in the final stages of preparing a PhD thesis which is based on his
`work in the field of ITS systems. This thesis identifies a generic
`architecture for intelligent agents which is used to provide the
`basis for realising the two main modules of an ITS system: the
`domain expert and the tutor.
`As part of the MOBIT project he is examining the possibility of
`delivering computer-based training material via W3 tools, the
`training domains for MOBIT being control of a nuclear power
`plant (with Scottish Nuclear) and the manufacture of computer
`systems (with Digital Equipment Scotland Limited).
`
`Page 13 of 13
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