Virtual Communities as a Crossroads for Global Knowledge
By Marco Padula, Amanda Reggiori, and Cristina Ghiselli
Preservation. Storage. Circulation. The new frontiers of the digital
age? In all probability, yes.
The Corpus AfricanisticumComunità virtuale per la cultura africana
in Italia, developed and maintained by the Institute for Multimedia
Information Technologies of the National Research Council is an
experimental prototype that demonstrates the process of the globalization
and universalization of knowledge that the synergy of new technologies,
communication, and specific disciplines can activate, exploiting
the interdisciplinary nature and the potentials for interconnectivity
and interaction peculiar to the Internet. By community we mean
a social group whose founding characteristic is communion: participation
by a number of members with the same objectives, sentiments, ideals,
intentions, and interestswhether of the living or with the past
through the bonds of memory. There are communities of people and
of things: a community of human beings is a collectivity cohesive
in participation; a community of things is a collection of objects,
sets of containers, and instruments for registering and organizing
documents and historical traces together with those not produced
by the same community of beings, of which they form the memory
[De Kerckhove, 1995].
An Internet site is an infrastructure supporting a virtual community
and the communication among the various communities of cyberspace.
The interaction that the new instruments like the Net both facilitate
and demand can stimulate the creativity of internauts and funnel
their participation into the production of collaborative energies.
With this prospect we can confront the theme of the redistribution
of knowledge, of the importance of sharing in it, and of how it
is the cornerstone of community life, cultural continuity, and
renewal [Lévy, 1994, 1995, 1997]. Collectivities as promotors
of significant relationships can eliminate the contradictions
between the South and North of the world and avoid the formation
of new areas of exclusion [Padula et al., 1998; Jensen, 1997,
It is interconnectivity that determines the establishment of the
infosociety, which has no territorial boundaries, is transnational,
is represented by a species that becomes community, is planetary
and global, and requiresas elements of positive growth through
the Netntegration and responsibility. The communicating community,
globalized in rethought time and space, makes flow its way of
life, but that flow would not exist without human participation
in the flow itself, as well as a link with reality.
Introduction of the new information technologies and electronic
media and, above all, of the Internet, has modified the relationship
between man and machine. The machine is no longer simply a computing
tool; it has become a means facilitating contacts between peopleeven
people of diverse cultures and countries. In this realm, interaction
no longer takes place exclusively between man and machine but
between one man and another, mediated by the machine: it has become
interactivity. The new volumes of the storage of data, of the
transfer of information, and of communication form what is almost
a symbiosis between man and machine as a kind of prosthesiscomputer
supported rather than directedand create a new system that is
not merely the digital representation of reality but that becomes
the possibility of creating virtual communities on the Net.
Searching for documentation, communicating, and interacting with
people are among the most community oriented of our daily activities.
Working communities that have agreed to live in the infosociety
extend beyond any corporate boundaries, calling for an extension
of our present concept of computer-supported cooporative work
to computer-supported community work, as suggested by Doug Schuler
[Schuler, 1994, 1998].
The increasing of digital archives is of primary importance for
the construction of a space in which the traces of the experience
that every member of the community brings to the group can be
collected. Moreover, the possibility of saving the comments and
discussion of the participants in a virtual community alleviates
the transitoriness of the contributions, making time for updating,
spreading, sharing, and developing the information available.
There is an urgent need for tools for thematic searches and for
the integration of data memorized in heterogeneous and distributed
archives. The data structures, transfer protocols, and complex
systems on which their management is based are currently the subject
of advanced studies. The role of technologists and designers is
to create a link in continuous tension between speculation and
pragmatism: while considering social needs, they are also introducing
the most abstract of ideas into the operating laboratory to conceive
solutions based on available and experimentable infrastructures,
methodologies, and languages. In this way, the virtual community
shortens the gap between technological innovation, its transfer,
and the employ of its products, so that we can expect environments
such as the social and technologicalwhich are today dividedto
become asymptotically convergent.
The immaterial trace of the physical object is what will remain
as testimony that can be repeated in an infinite number of copies
an infinite number of times. It will even be possible to increase
and renew itwithout losing its initial state and progressionsand
always maintaining a clear view of its path through life, verifiable
at every stage. And if preservation is a constant in the current
debate of technological disciplines as well as of classical disciplines,
then the storing of information will benefit equally from information
technologies. The archives' physical location, which has always
been a part of man's material culture, has no impact today on
the retrieval of the object: it is only the physical custodian
of the thing, but it can be visitednot only in reality but also
through a process of formalization and cataloguing that makes
the search easier. Consequently, electronic media also facilitate
a new dissemination of knowledgeone that is extensive, horizontal,
In the virtual community, individual identity and features are
no longer inportant. Nor are professional profiles or affiliations:
only the documents circulated, the actions undertaken, and their
effects are. A virtual community is deterritorialized: detached
from physical and geographic space but dependent upon the possibility
of connecting with the Net, which permits or denies inclusion
in the virtual community. Since the invention of digital systems,
we speak of real time, in which an instant is a gesture followed
immediately by a reaction. Solar time no longer exists; instead,
we have potential immediacy: the interval is measured in the time
it takes the person addressed to answer and in the speed of the
instruments involved. Time in virtual space is measured in acts
The virtual community is responsible for the evolution of the
document, which now resembles a channel of communication more
than it does an artifact. It becomes the concrete realization
of a semantic emergencewithout a predefined description of the
contents; its singularity disappears and its outline is not precisely
indicated, unless by the URL (uniform resource locator), or Net
address, of its heterogeneous components: there is no longer a
beginning and predefined end to the reading. As a consequence
of its transitoriness, what matters in a document is the management
in time of its successive versions, the references to its dynamic
components, and the access to important information. The material
being of the object becomes a secondary aspect: the object can
be seen in a completely artificial situtation [Padula and Musella,
1997]. Virtual communities of things allow the artifical world
built by physical manlibraries, museums, and so onthat is the
human archives, to be even more artificial, since the material
given of the relationship with the object is of no import, the
object being simulated in the digital mode, allowing physical
man in his search in the virtual world easy access to the resources
of knowledge, much more swiftly, and without having to move from
his workstation. He decides what, how, and, above all, when to
access the enormous quantity of information available on the Net.
He can preserve forever, in digital form, whatever he retrieves,
and perhaps these new archives will be what, in fact, is transmitted
On the Net, real communities are transformed into virtual communities
of navigators, whose existence depends on their interactive activity.
The virtual community of navigatorsof all of those searching
for knowledge on the Netis an effective support for the real
community, coping with problems that cannot be dealt with in reality
but that can be solved when relocated in the virtual world.
A virtual community on the Net requires two primary elements/sources
in order to exist. On one hand are the individuals who make up
the community and measure themselves against each other within
it: the community of people, composed of collectivities animated
in the active and participative, communicative, interactive mode.
Interactivity is, in fact, the characteristic that makes it possible
to communicate and take part in the construction of a renewed
space of knowledge, to which each member is called to make a personal
contribution. The interactivity that the new instruments like
the Net both facilitate and demand can stimulate the creativity
of the internauts and direct their participation toward the production
of collaborative energies. On the other hand, there must be a
reservoir of materials from which to draw the knowledge that in
the real world is contained in museums, libraries, collections,
and documents: the community of things. Virtual communities of
things represent archives, which are continuously consulted, updated,
and expanded by the members of the community, taking advantage
of the possibilities the new information and digital technologies
provide. These communities shall be the immaterial archives of
human memory [Reggiori, 1996].
The communities of persons organize the virtual communities of
things that constitute the archives of man's memory and that represent
the first step in the building of a collective memory, in that
they make it possible to reach the object of interest no matter
where it is located and no matter where the user is connected.
Virtual communities of things also make it possible to organize
surroundings for an objectthat is, discussion, analysis, an exchange
of ideas, or a subjective activitythrough the expansion of the
archives, or through corrections, or through variations when errors
or imprecisions have been discovered.
Interconnectivity and navigation allow members of a virtual community
to move in the space of the Nein cyberspaceand to access, through
simulation, the virtual community of objects, the archives, patrimony,
and information base of the virtual communities of persons.
The skeleton of a virtual community
The infrastructure of a virtual community is an Internet site,
developed through programming applications and languages that
are publicthat is, ones that available at no charge on the Net.
This infrastructure provides for preservation, and it proposeswhen
it does not demanddissemination through use.
The Corpus AfricanisticumComunità virtuale per la cultura africana
in Italia (http://africa.itim.mi.cnr.it, figure 1), addressing
for the moment Italian-speaking users, was created to exploit
the technological potentials for the preservation, storing, and
circulationplanetary and globalof African culture as documented
in Italy, as a documentary support for research in African culture
through multimedia documents in archives that can be consulted
directly in Internet, and with the intention of creating a relational
space for immigrants in Italy. The activity of the historian,
in fact, relies on extensive research through museums, libraries,
and archives located in general in different cities and countries
[Mozzati and Padula, 1996]. The Corpus is a global/virtual library
from which information can be drawn, thereby eliminating the problem
of the geographic distances separating the different archives
that form it and the persons accessing itand making it possible
to bring together heterogeneous data (texts, images, numbers)
in a single document (figure 2).
Figure 1. The home page of the Corpus Africanisticum - Comunità
virtuale per la cultura africana in Italia (Virtual Community
about the African Culture in Italy)
Organization of the immaterial archives of human memory
Preservation, sustained by instruments for online storage, permits
the retrieval of documents through access to the archives from
remote stations, free of the bonds of the physical place of material
filing, and supporting the activity of the researcher.
As initially designed, the Corpus Africanisticum was simply a
virtual community of things bearing on the theme of African culture
in Italya reprocessing in the virtual context of the classic
concept of the library and applying the new information technologies.
This aspect has been maintained and introduced into a corrected
idea of the virtual community and continues to be an instrument
for studies and research adopting the new technologies. The initial
objectives of the Corpus included virtual elimination of the geographic
distance of heterogeneous and distributed archives and the reorganization,
through digital coding, in a single informative objectthe multimedia
documentof all of the media and communication languages (text,
images, sound, and, when pertinent, video). This object was assigned
the characteristics of the hypertext: shaping it in a nonsequential
but network structure, composed of a complex of information units
(nodes) and connections (links). An intricate information organization,
transmitted in this manner, has transformed the Corpus into a
complex of hypermediathat is, multimedia hypertexts connected
on the Net.
The Corpus, as a community of things, takes the form of a thematic
multiarchive: a collection of heterogeneous and distributed archives
grouped by subject and equipped with a structure for accessing
it that facilitates the searchby subjectfor information. Its
design was inspired by the theory of MultiDataBase Systems [Pitoura
et al., 1995]: systems for the creation of an environment for
the integration of and concurrent access to multiple, distributed,
and heterogeneous databases and supplying a concise but global
view of all of the archivesa view that is not limited by the
technical choices made during its realization. The various archives
are integrated through several levels of synthesis relating the
schemata of the different archives to each other. Each schema
describes the structure of the archive by the type of data contained,
how these are related, and the operations that can be performed.
Every archive has its contents and a local schema that can be
consulted autonomously through programs that vary depending upon
its structure and the interests of the user. To integrate the
data of local archives, the local schemata must be concisely combined
in a common model (CDM, or common data model) of representation.
The mechanisms currently in use for searching in document archives
by keywords or values require the sequential access and querying
of archives, which is time-consuming and gives results that are
difficult to visualize. Progressively transforming the local schema
into a sequence of overlapping schemata through the use of a CDM
presumes the construction of an ontologythat is, a detailed description
of a conceptualization designed for reuse in different domains
of interest or data structures. The term conceptualization means
a set of concepts, relations, objects, and constraints defining
a semantic model of a domain of interest.
Constructing the Corpus also meant constructing an ontology, recognizing
the recurrent elements among the data at the global level, and
identifying the links between the various elements of informationcomponents
of the heterogeneous documents. This made it possible to recatalog
the contents of local archives by subject and to assign the semantic
attributes that provide significant representation of the various
pieces of information.
The process produced a structure combining the semantic attributes
in a unified view of the different archives that allowed the search
for documents composed of heterogeneous elements. The definition
of this structure is an operational use of the CDM. The same archive
may belong to more than one domain of interest defined on the
basis of suited sets of concepts belonging to theontology. The
reference to the domain is particularly useful during the querying
of archives because queries addressed to the thematic multiarchives
can be translated into terms accessing the local archives involved,
thereby optimizing information retrieval.
From the technical point of view, this process requires the construction
of a complex data structure that maps the external users view
onto the local schemata of the various archives when they are
connected with the multiarchives. The subject cataloging of new
archives precedes their inclusion in the multiarchives. A tool
has been designed for the automatic creationdepending on the
cataloguingof the semantic links among the new archives proposed
and those already included in the multiarchives.
The user is not aware of consulting heterogeneous and distributed
archives, because the formulation of the query and the results
obtained are as homogeneous as possible. The user may want to
select only part of the archives available. If just one archive
is selected, the concepts represented by the local schema of the
archive are visualized. If there is no common domain, the program
asks that the query be specified by value for a generic comparison.
In this way, queries are divided and translated into the syntax
of the individual querying programs of the archives. The result
is visualized as a single object (figure 2).
Figure 2. An example of the result of a query to the Corpus
The heterogeneous, distributed archives created via different
applications can be accessed in the Corpus through an organization
by sections (figure 3).
Figure 3. Access to the virtual community of objects
The Library (Biblioteca) includes archives generated with specific
systems of information retrieval for the organization and retrieval
of texts. Textual archives can be expanded with images and hypertextual
connections among documents.
Information on the Country (Informazioni sul paese) accesses a
relational database containing, for example, information on social,
geographic, and economic conditions in African countries and on
the possibility of Internet connections.
The H-teca is composed of archives of documents in HTML (hypertext
markup language) concerning the African continent. It is a rough
mapping of the resources on the Internet that are dedicated to
Africa. The data have been partially cataloged, stored, and organized
through information retrieval programs developed for their retrieval
by direct querying of the archives that contain them.
The potentials of modalities for the preservation and use of information
through communication depend greatly on technological innovation.
We are currently defining tools and methodologies for the reorganization
of the existing material to favor more-dynamic, more-creative,
and more-interactive participation by members of and by visitors
to the virtual community. Users select, from the reply of the
multiarchive, the data of interest for their work, creating a
new object summarizing these, which can in turn be cataloged and
stored in a new archive.
A Path toward the New Technologies
Another objective of the Corpus is to provide an updated laboratory
in which new technological tools supporting social and cultural
needs can be proposed and experimented on as they appear on the
scene. Consequently, the infrastructure of the virtual community
must keep pace with the trend of technological progress in order
to understand the usefulness and applicative, or methodological,
innovation of the instruments proposed and to see whether they
can be adapted and reused in different environments, or whether
further developments can be proposed.
Today the technological challenge to the Corpus, which is currently
in a prototype version, is the creation of tools for growth of
the Corpus through the personalization of information and its
reprocessing according to the new technological standards of the
World Wide Web. These are matters purely of infrastructure (such
as the protocols for communicating and transferring data on the
Net), as well as difficulties in the presentation of documents
(which changes with the type, or even the version, of browser
employed, and which does not, in any case, meet current graphic
demands), and of the problem of the explicit rendering of the
significance of a document to improve information retrieval.
The approach taken to solve these problems considers (1) the use
of new languages that integrate or, in the end, replace HTML and
(2) the possibility of assigning the client or the browser a greater
role in the processing (depriving the latter of its autonomythat
is, facilitating the interpretation of different syntaxes of the
HTML through tools that allow extension of the language itself).
The recently proposed metalanguage, XML (extensible markup language)
[Bray et al., 1998] permits the definition of new syntactical
elements, specifying separately the content, structure, and style
of representation. XML is a language for a structured approach
to the description of documentsthat is, specifying the component
parts with their relative attributes. A DTD (document-type definition)
is composed in which the syntax and the semantics of the tags
are defined. XML extended with DTD is used for describing an instance
of a document and organizing the contents. The DTD provides a
grammar that can automatically verify whether a document derived
from it is a valid XML document. Representation of the various
elements can be left to the author of the document, who can define
this information either within the DTD or in attachments written
in languages devised for that purpose, one of which is the emerging
XSL (etensible stylesheet language). XSL allows the browser to
personalize the visual presentation of the XML document without
any interaction with the server. The potential of XML associated
with XSL lies in the fact that, by the application different stylesheets,
the same XML document can be used by different users, who adapt
its presentation to their own needs, and to the interface, or
applications, used. The fact that a document can be formally and
automatically analyzedfocusing separately on its structure and
presentationmakes it possible to identify any recurring components
of the document and to determine their importance on the basis
of their position in the textual hierarchy. We can expect XML
to become the basic tool for the exchange of data on the Internet.
XML is a meta-language that defines new languages, including new
metalanguages. A good part of the scientific community considers
XML a panacea for the various problems regarding the WWW. For
example, the XOL language (XML-based ontology exchange language)
[Karp et al., 1999] allows the formal definition of the set of
concepts, relationships, objects, and constraints characteristic
of a domain of interestsuch as African culture in Italy. The
definition of an ontology can be expresssed in XOL, and this definition
used as a tool for mediating among different formats and uniforming
them. A specific case is that of uniforming the schemataor instances
of documentsmanaged by RDBMS, OODBMS, or IRS, all belonging to
the same thematic domain. Consequently, in the case of Africa,
XOL is a valid candidate for expressing the CDM.
Ways of breaking down into fragments and storing XML documents
in specialized databases and, vice versa, tools for translating
the structure and contents of the databases in XML documents are
currently being defined. XML documents are roughly classified
as datacentric documents for further processing, characterized
by a fairly regular structure, fine-grained data, and documentcentric
documents meant for direct, human communication and characterized
by an irregular structure and larger-grained data [Bourret, 1999;
XML documents are transferred to and from a database by mapping
the document structure to the database structure and, vice versa,
using a template- or model-driven approach. In the former, commands
are embedded in a template that is processed by data transfer
programs. In the latter, an ontology expressed in an appropriate
language (XOL) is used as an intermediate in order to map the
structure of the XML document to the structures in the database
and vice versa.
Relational databases, while suitable for storing datacentric documents,
do not constitute the optimal solution for storing documentcentric
documents, because such databases cannot efficiently provide for
order, hierarchy, irregular structure, and fields of variable
length. They can, with certain limitations and leaving much of
the work to the user, be used to store XML documents, as described
by Mark Birbeck on the XML-L mailing list: a DTD can be translated
with a five-table system. In this scenario it is inevitable that
we must face the new technological challenge of defining a new
infrastructure for the Corpus, in its function as multiarchives
and support for documents customization, using the XML as a metalanguage
to standardize the proposed CDM structure. Consequently, we are
taking two steps:
- Designing and producing tools in Java that allow the dynamic construction
of a reference ontology for the material present in the Corpus
Africanisticum, so that it can be constantly updated by including
new archives or new documents with only a minimum effort on the
part of the user
- Modeling the schemata of the local archives by using a DTD compatible
with the ontology created. Exploiting developments in the XOL
language, with which every possible ontology can be easily converted
into a DTD
These activities will produce the skeleton of the new infrastructure
of the Corpus Africanisticum virtual community, for which we are
designing support tools for:
- An interface in Java that can identify, once the set of archives
to query has been chosen, the DTD of the corresponding domain
- Translation of the user's specifications into the syntax of the
- Assignment to each archive of a component DTD and the principal
DTD, so that the results will be given in an XML document with
a structure that depends on the domain but that is homogeneous
in its various elements
- Presentation of the result of a query in the form of a structured
document that can be recataloged and included in a new database
or, even better, the organization of which can be exploited to
create paths for personalized navigation
In this way, XML can also be used as a language to define the
user-system interface for interaction, querying, and visualization.
Animating the Virtual Community of Navigators
The fruition of the community is supported by tools that manage
the services for interaction and interactivities and, together
with the consultation for navigation, allow an exchange of comments,
notes, and messages from the same working environment and through
the same channel.
The Corpus offers instruments/services for communication and participation
within this neocommunity (figure 4), subsidiary of the real one,
through a CMC (computer-mediated communication) in either synchronous
mode (communication between two or more interlocutors, as in a
normal telephone call or face-to-face) or asynchronous mode. Members
of the Corpus Africanisticum virtual community can communicate
with each other on the Net through services such as e-mail, news
groups, forums, and chat lines.
Figure 4. CMC services offered by the virtual community
With e-mail they can send messages in asynchronous mode to other
people or programs. Messages received in the electronic mailbox
can be read at a later time.
A News group is a permanent electronic conference in which people
with a particular interest in common participate. Messages sent
to a news group, unlike e-mail, are not addressed to a single
individual but get posted for a certain length of time on a virtual
bulletin board where anyone who wants to can read and comment
on them. It is a tool for asynchronous, collective, and even moderating
The Corpus also has a forum service, with three discussion groups:
the General Forum, the Guestbook, and the Calendar of Events.
The chat line is a conversation in real time and allows for interactive,
synchronous exchange of messages. One person writes a message
and receives the answer by his interlocutor immediately on his
screen. Usually, no control is exercised over who particpates
or the subject discussed. Nor does any trace remain of the messages
exchanged in a chatting session. The chat line of the Corpus Africanisticumto
restrict communications to the theme of the Corpus has been designed
in an asynchronous mode, although the user does not perceive it
as such. The service is accessed by registering one's name (nickname),
e-mail address, and password. These data are sent to the Web administrator.
Once registered, the user may begin to communicate with the other
participants on the list of persons connected at that moment:
he selects the person he wants to chat with by sending a message
through the form shown on the page. Both the messages he sends
to other members of the virtual community and those sent by other
members to his attention can be viewed on the screen.
Digital society gives added value to preservation by allowing
fruition of the object (hypermedia document), making it possible
to operate on a shared base of documents and adding one's own
contributions to extend the boundaries of the documents, using
the services for interaction to add creative, dynamic, and transitory
surroundings. The virtual community is responsible for the evolution
of the document, which now resembles a channel of communication
rather than the subject of a conversation, more similar to our
idea of communication than to that of artifact. It becomes the
concrete expression of a semantic emergence, without a predefined
description of its contents; its uniqueness vanishes, and its
contours are not precisely indicated, except by the URL, the addresses
of the Net, and its heterogeneous components; and there is no
longer a predefined beginning and end to the reading. As a consequence
of its transitoriness, what counts in a document are management
in time of its successive versions, management of the references
to its dynamic components, and access to important information.
The materiality of the object becomes an aspect: the object can
be seen in a situation of complete artificiality. Virtual communities
of things allow the artificial world built by mansuch as libraries
and museums, that is, human archivesto be even more artificial,
because the material relationship with the object, which is simulated
in the digital mode, has no relevance. Physical man in his research
in the virtual world can more fully exploit the resources of knowledge
because he can do so with little effort, much more rapidly, and
without moving from his workstation.
The virtual community provides a collaboratory [CTT, 1997]that
is, a virtualworkplace for a technological development that originates
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