Temporal Resources Dynamic Web Evolutionary Resources
Institute of Information Theories and Applications FOI ITHEA
In this paper the key features of a two-layered model for describing the semantic of dynamical web
resources are introduced.
In the current Semantic Web proposal [Berners-Lee et al., 2001] web resources are classified into static
ontologies which describes the semantic network of their inter-relationships [Kalianpur, 2001][Handschuh &
Staab, 2002] and complex constraints described by logical quantified formula [Boley et al., 2001][McGuinnes &
van Harmelen, 2004][McGuinnes et al., 2004], the basic idea is that software agents can use techniques of
automatic reasoning in order to relate resources and to support sophisticated web application.
On the other hand, web resources are also characterized by their dynamical aspects, which are not adequately
addressed by current web models.
Resources on the web are dynamical since, in the minimal case, they can appear or disappear from the web and
their content is upgraded. In addition, resources can traverse different states, which characterized the resource
life-cycle, each resource state corresponding to different possible uses of the resource. Finally most resources
are timed, i.e. they information they provide make sense only if contextualised with respect to time, and their
validity and accuracy is greatly bounded by time.
Temporal projection and deduction based on dynamical and time constraints of the resources can be made and
exploited by software agents [Hendler, 2001] in order to make previsions about the availability and the state of a
resource, for deciding when consulting the resource itself or in order to deliberately induce a resource state
change for reaching some agent goal, such as in the automated planning framework [Fikes & Nilsson,
1971][Bacchus & Kabanza,1998].