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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 Africanisticum–Comunità 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 interests—whether 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, 1998].

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 requires—as elements of positive growth through the Net—ntegration 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 people—even 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 prosthesis—computer supported rather than directed—and 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 technological—which are today divided—to 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 it—without losing its initial state and progressions—and 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 visited—not 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 knowledge—one that is extensive, horizontal, and intercultural.

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 of communication.

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 emergence—without 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 man—libraries, museums, and so on—that 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 as memory.

On the Net, real communities are transformed into virtual communities of navigators, whose existence depends on their interactive activity. The virtual community of navigators—of all of those searching for knowledge on the Net—is 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 object—that is, discussion, analysis, an exchange of ideas, or a subjective activity—through 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 Ne—in cyberspace—and 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 public—that is, ones that available at no charge on the Net. This infrastructure provides for preservation, and it proposes—when it does not demand—dissemination through use.

The Corpus Africanisticum–Comunità 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 circulation—planetary and global—of 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 it—and 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 Italy—a 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 object—the multimedia document—of 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 hypermedia—that 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 search—by subject—for 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 archives—a 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 ontology—that 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 information—components 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 user’s 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 creation—depending on the cataloguing—of 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 autonomy—that 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 documents—that 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 analyzed—focusing separately on its structure and presentation—makes 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 interest—such 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 schemata—or instances of documents—managed 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; Widom, 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 various archives
  • 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 participation.

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 Africanisticum—to 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.

Conclusions

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 man—such as libraries and museums, that is, human archives—to 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 virtual—workplace for a technological development that originates and is modulated by social needs.

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