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Brian Kelly
UK Web Focus
Email Address
B.Kelly@ukoln.ac.uk
UKOLN
University of Bath http://www.ukoln.ac.uk/
UKOLN is funded by the British Library Research and Innovation Centre, the Joint
Information Systems Committee of the Higher Education Funding Councils, as well as by project funding from the JISC’s Electronic Libraries Programme and the
European Union. UKOLN also receives support from the University of Bath where it is based.
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See
<URL: http://www.ukoln.ac.uk/ web-focus/ > for trip report, these slides, etc.
• Introduction
• Tim Berners-Lee's Keynote talk
• W3C Tracks at WWW 7 Conference
• Developer's Day
• Keynote on Java
• Papers
• Search engines
• Characterisation
• Question
• Metadata
• Markup
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WWW 7 Conference:
• Held in Brisbane, Australia from 14-18
April 1998
• About 1,400 participants
• Exciting new technology RDF
• See <URL: http://www7.conf.au/ >
• Conference papers online for short period
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Tim Berners-Lee's opening keynote talk talked about " evolvability " of the web:
• Evolution of markup languages and data
• Goal: version 1 software partially understands version 2 data.
• Based on " we will be smarter in the future "
• Goal: version A software partially understands version B data.
• Based on " Others will be smarter than us "
• Use web as the registry (decentralised evolution)
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RDF (Resource Description Framework ):
• See a document as a combination of logical assertions
• Draw conclusions by combining many documents
Global reasoning engines, based on RDF could be "devastating"
" Is there a green car for sale for around $15,000 in
Queensland?
"
"Get involved in RDF, XML, Schemas"
"Design for evolvability"
See <URL: http://www.w3.org/Talks/
1998/0415-Evolvability/slide1-1.htm
>
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W3C (World Wide Web Consortium):
• Gives update on W3C activities in the W3C
Track at WWW Conferences
• Covers:
– User Interface Domain
– Architecture Domain
– Technology and Society Domain
• Talks available at
<URL: http://www.w3.org/
Conferences/WWW7/W3CTrack.html
>
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HTML Futures:
• Talk given by Dave Raggett
• HTML 4.0 now complete. Need to look at HTML futures.
• Workshop in US in May. See details, including position papers at <URL: http://www.w3.org/MarkUp/future/ >
• See Dave's slides at <URL: http://www.w3.org/Talks/
1998/0416-WWW7-HTML/ >
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Mobile Computers
• Importance of mobile computers (PDAs, phones, car computers, etc.) NOTE Dearing report
• Relationship with accessibility issues
• Challenges:
– Small screens – Long round trip times
– Limited processing power / memory
• Solutions:
– Abbreviations for headings
– Use of styles (rather than, e.g., tables)
– Expanding and collapsing outlines
– Aural and visual media (headings spoken, read body)
– HTML 4.0 and CSS 2.0
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MML:
• Math(s) Markup Language
• An XML Application
• W3C Recommendation agreed on 7 April
1998
• Java and ActiveX renderers
• Dave Raggett has authoring tool
(Windows 95 application)
• See <URL: http://www.w3.org/Math/ >
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Architecture Domain:
• Promote coherent Web architecture
• Automate information management If a decision can be made by machine, it should
Working on:
• HTTP/1.1 and HTTP/NG
• Jigsaw server (in Java, freely available)
• XML
• SMIL
See <URL: http://www.w3.org/Talks/
1998/04/WWW7-Arch/ >
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XML:
• Extensible Markup Language
• Addresses HTML's lack of evolvability
• XML 1.0 Recommendation in Feb 1998
• Note well-formedness :
Make end-tags explicit: <LI>...</LI>
Make empty elements explicit: <IMG ...
/ >
Use consistent upper/lower case
• and valid :
Need DTD
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• Extensible:
<PART>M-471</PART>
• Multiple names spaces:
<?xml:namespace ns="http://foo.org/
1998-001" prefix=" i ">
<P>Insert < i :PART>M-471</i:PART></P>
• Sharing document structures:
– It's hard
– It's necessary
– It's worth it
See <URL: http://www.w3.org/Talks/
1998/04/WWW7-XML/ >
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HTTP/0.9 and HTTP/1.0:
Made the Web popular
Design flaws and implementation problems caused poor performance
HTTP/1.1:
Addresses some of these problems
Performance benefits!
Is acting as fire-fighter
Poor usage counting
Not sufficiently flexible or extensible
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HTTP/NG:
• Based on convergence of Internet protocols
• Two W3C Working Groups:
Protocol Design:
Redesign Web as distributed object application
Web Characterisations:
Study Web usage and form requirements
New log format for easier collection and anonymisation
See <URL: http://www.w3.org/Talks/
1998/04/WWW7-HTTP-NG/ >
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WAI (Web Accessibility Initiative):
• Ensures web specs address accessibility issues
Authoring:
• First draft of Page Author Accessibility Checklist and Guidelines available at
<URL: http://www.w3.org/TR/
1998/WD-WAI-PAGEAUTH-0203 >
Software
• User agent / Authoring tools guidelines being produced
See <URL: http://www.w3.org/Talks/1998/04/
WWW7-WAI/ >
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Domain activities cover:
• PICS
• Digital Signature Initiative
• Privacy (P3P)
• Metadata (RDF)
• Security Interest Group
• Public Policy Interest Group
• Electronic Commerce Interest Group
See <URL: http://www.w3.org/Talks/
1998/04/WWW7TandS/ >
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P3P (Platform for Privacy Preferences):
• Privacy concerns are a current barrier to Web development (Note Tim Berners-Lee's interview in Australian press)
• P3P project developing methods for exchanging
Privacy Practices of Web sites and user
• Documents on architecture and vocabulary available
• See <URL: http://www.w3.org/P3P/ >
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RDF (Resource Description Framework):
• Highlight of WWW 7
• Provides a metadata framework (" machine understandable metadata for the web ")
• Based on ideas from content rating (PICS), resource discovery (Dublin Core) and site mapping (MCF)
• Applications include:
– cataloging resources
– electronic commerce
– resource discovery
– intelligent agents
– digital signatures – content rating
– intellectual property rights – privacy
• See <URL: http://www.w3.org/
Talks/1998/0417-WWW7-RDF >
RDF:
• Based on a formal data model (direct label graphs)
• Syntax for interchange of data
• Schema model
Resource
PropertyType
Property page.html
RDF Data Model
Cost
Value
£0.05
Cost page.html
PropObj
InstanceOf
PropertyType
PropName
£0.05
Value
ValidUntil
11-May-98
Cost
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ValidUntil
11-May-98
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Example of Dublin Core metadata in RDF
<?xml:namespace ns="http://www.w3.org/TR/
WD-rdf/" prefix="rdf"?>
<?xml:namespace ns="http://purl.org/dublin_core/ schema/" prefix="dc"?>
<rdf:RDF>
<rdf:Description RDF:HREF="page.html">
<dc:Creator>John Smith</dc:Creator>
<dc:Title>John’s Home Page</dc:Title>
</rdf:Description>
</rdf:RDF>
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Mozilla (Netscape's source code release) provides support for
RDF.
Mozilla supports site maps in RDF, as well as bookmarks and history lists
See Netscape's or
HotWired home page for a link to the RDF file.
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RDF is a general-purpose framework
RDF provides structured, machineunderstandable metadata for the Web
Metadata vocabularies can be developed without central coordination
RDF Schemas describe the meaning of each property name
Signed RDF is the basis for trust
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" So You Want To Be An XML Developer "
Talk by Tim Bray, Textuality
See <URL: http://www.textuality.com/
WWW7/ >
Useful resources:
Annotated Spec at <URL: http://www.xml.com/axmls/axml.html
>
XML FAQ at <URL: http://www.ucc.ie/ xml >
Other pages at <URL: http://www.sil.org/ sgml/xml.html
>
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XLink
• Aims to provide sophisticated hyperlinking functionality missing in HTML
• Formerly known as XML-LINK and XLL
• See <URL: http://sil.org/sgml/xll.html
>
• XLink working draft is stable, though new versions due out
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England
XLink provides:
France
• Links that lead to multiple destinations
• Bidirectional links
• Links with special behaviors:
– Expand-in-place (similar to < IMG SRC >)
– Replace (similar to < A HREF >)
– Create new window
– Link on load (similar to < IMG SRC > or redirect)
– Link on user action
• Link databases
<commentary xml:link="extended" inline="false">
<locator href="smith2.1" role="Essay"/>
<locator href="jones1.4" role="Rebuttal"/>
<locator href="robin3.2" role="Comparison"/>
</commentary>
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XPointers:
• Based on TEI work
• An XPointer specifies a location in an XML tree structure
• For example:
ID(foo).CHILD(4,SEC).CHILD(1,ABSTRACT) addresses the first XML ABSTRACT element within the fourth SEC element within the element with ID attribute " foo " in a document
• To use:
<A HREF="http://www.xyz.com#ID(foo)
CHILD(4,SEC)CHILD(1,ABSTRACT)">
• Note the working draft is not stable
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Keynote talk by James Gosling :
• Positive about Java futures
• "This is the year the performance problem disappears." JIT compiler performance is close to C. Betters JVMs available (e.g. HotSpot).
• Java is being ported to PDAs, phones, smart cards, …
Q. How serious are browser incompatibility problems?
A. Netscape made serious error at one point. There are also bugs in IE. Activator may enable a functioning JVM to be installed (note supports
< OBJECT > tag).
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218 papers submitted.
54 papers, 43 short papers, 13 posters, 5 doctoral consortium papers and 6 panel abstracts published
Brief comments on papers of interest to web software developers and information providers.
General themes:
• Java was widely used to implement ideas
• Several papers on analysis of link structures to improve searching
See <URL: http://www7.conf.au/programme/ fullprog.html
>
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Three papers.
Specifying Metadata Standards for Metadata Tool
Configuration by Andrew Waugh, CSIRO, Australia
Excellent paper showing how the expense of producing metadata requires a generic metadata editor
The Limits of Web Metadata and Beyond by Massimo
Marchiori, MIT, USA
This paper describes how fuzzy techniques can be used to automatically generate metadata for existing resources
Structure Graph Format: XML Metadata for
Describing Web Site Structure by Liechto et al
Producing site maps based on linking and directory structures
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An Extensible Rendering Engine for XML and HTML by Ciancarini et al, Bologna University
This paper describes how Java can be used to provide browser support for new HTML / XML tags
<APPLET archive="displets.zip">
<PARAM NAME="def" VALUE = "
<TAG name='reverse' src='reverse.class'>
</TAG> ">
..
<P>This text is displayed as <REVERSE>white text on black</REVERSE>
Information (shortly) at http://www.cs.unibo.it/~fabio/ displet.html
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http://google.stanford.edu/
The Anatomy of a Large
Scale Hypertextual Web
Search Engine Brin & Page,
Stanford Univ
• Describes Google, a largescale search engine developed for research purposes
• Uses link information
• Use of service and feedback is encouraged
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Summary of Web Characterisation by Pitkow
An excellent review of web characterisation studies, including:
– Client studies
– Proxies and gateways
– Server
– Websites
Some conclusions:
No. of page requests per site Mode of 1!
Site popularity
Document life span
25% of servers 85% traffic
About 50 days
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One paper, in Hypertext and Hypermedia session, on web management
WSDM: A User Centred Design Method For Web
Sites by De Troyer et al
This paper proposes a design methodology for web-kiosks.
The paper gives references on methodologies for website design.
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• WWW 8 to be held at Toronto in May 1999
• WWW 9 to be held in Amsterdam in 2000
• Call for papers for WWW 8 shortly
• Closing date December 1998
• For information on WWW protocol developments see uk-web-focus-w3c@mailbase.ac.uk
list