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DigiCULT
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Info
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tool in the fields of harvesting and archiving
Web documents.The NWA Toolset is licen-
sed as Open Source under the GNU
General Public License (GPL:
http://www.gnu.org/licenses/licenses.html#
GPL). It can be downloaded from
http://nwa.nb.no/ or SourceForge
(http://sourceforge.net/).
W
eb document archives can be very
complex, comprising large numbers
of documents, objects which are separate
and yet part of the document (e.g. images
displayed within a Web page) and several
different versions of the same Web docu-
ment (for example, documents downloaded
from the same URL on different dates). Last
December, the Nordic Web Archive
(http://nwa.nb.no/) released the NWA
Toolset, a freely available solution for sear-
ching and navigating archived Web docu-
ment collections.
I
n development since November 2000,
the Toolset was built using PHP, Perl and
Java and utilises open standards like the http
protocol and XML. It is used through a Web
browser and requires no special plug-ins.
The NWA Toolset consists of three main parts:
1 The Document Retriever delivers
archive objects and associated metadata to
the Exporter and the Access Module
upon request. It is adaptable to fit the
needs of different archives.
2 The Exporter transforms archived objects
and associated metadata into an interme-
diate XML format named the NWA
Document Format.The NWA Docu-
ment Formatted document collection is
then fed to the indexer of a search engine.
3 The Access Module interfaces both the
search engine and the Document
Retriever, thus giving the user the
possibility to search, browse and navigate
the archived Web documents.
T
he Toolset can be adapted to fit the
needs of individual Web document
archives and, when used in conjunction
with a Web archive, a search engine (and
abstraction layer), becomes a useful support
A
DS has set up two syndicated news-
feeds, one for news and events, and the
other containing information on new col-
lections added to the ADS Web site. Updates
are transferred by including a very short
(invisible) script within the HTML code of
any Web page which displays a list of headli-
nes and links to the pages where further
information can be found.When data are
altered, or new information is entered, the
updates are syndicated to anyone using the
newsfeed, keeping remote Web sites up to
date without the need for repeated editing.
T
his Open Source tool is constructed
using the RSS standard version 1.0.
RSS (which stands for Really Simple
Syndication) is a Web content syndication
format which conforms to the XML 1.0
specification and is based on the Resource
Description Framework (RDF). Each RSS
file contains a list of items, each of which is
identified by a link and has metadata associ-
ated with it.The most basic metadata sup-
ported by RSS includes a title and descrip-
tion for the link; in news headlines these
first paragraph or a summary, for example.
I
nformation from both ADS newsfeeds
and instructions on how you can include
the headlines in your own Web page can be
found at http://ads.ahds.ac.uk/rsscode.html.
More general information about the RSS
specification can be found at
http://web.resource.org/rss/1.0/ and links
to RSS resources, tutorials, news and tools
are available from RSSInfo (http://blogspa
ce.com/rss/). Syndication such as this bene-
fits organisations in terms of eliminating
obsolete information, standardising format-
ting of `list-type' information, reducing time
spent editing Web pages, and improving the
quality of the information presented.
O
PEN
S
OURCE
T
OOLS
RSS NEWSFEED AT THE
ARCHAEOLOGY DATA SERVICE
NWA TOOLSET
T
HE
P
APER AND
I
NK OF THE
F
UTURE
?
Newly released into the field of poly-
mer electronics is a rollable display
technology suitable for reading e-mail,
and potentially maps or e-books, which
takes up no more space than a pen. The
black-and-white displays are 320 x 240
pixels, have a resolution of 85 ppi, offer
four shades of grey and contain nearly
80,000 thin-film transistors. The flexi-
ble, active-matrix backplane is roughly
a quarter the thickness of a sheet of
paper and is attached to a thicker front-
plane of reflective electronic ink.
The flexibility of the displays allows
them to be tightly rolled up for carry-
ing or storage. This is made possible by
`electronic ink' developed by E Ink
(http://www.eink.com/) where transis-
tors are used to switch pixels under an
electric field, the particles becoming
stable when the power is switched off.
These active-matrix displays are there-
fore ideal for low-power mobile appli-
cations.
Polymer Vision
(http://polymervision.nl/), established
by Philips Research, is initially manu-
facturing only 5000 of the new `elec-
tronic paper' displays per year, but is
confident that their updateable conve-
nience will result in the development of
the technology into the future.