David Brosset

MODELING OYSTER FARMING ACTIVITIES IN COASTAL AREAS: A GENERIC FRAMEWORK AND PRELIMINARY APPLICATION TO A CASE STUDY

We present an approach for modeling oyster farming activities under spatio-temporal constraints. Combining an object-oriented geodatabase, a geographic information system and a multi-agent model, the methodology developed here offers a formal framework for analyzing the variability of the conditions in which activities are conducted and for evaluating how production systems adapt to this variability. A prototype specific to the Bay of Bourgneuf (France) was developed to study the spatio-temporal variability of oyster growth according to the quality of coastal waters and the oyster production strategy.

Location-and temporal-based services for nature-society interaction regulation

With the surge of mobile devices and applications, knowledge base browsing and querying facilities must be adapted to new kinds of users and services. Space and time databases are concerned and as such are the subject of this article. Within a mobile context, data retrieval services must take the location of the call into consideration as regards space and time, insofar many pieces of information do depend on ‘where’ and ‘when’ constraints. We present here with a general object model dedicated to specifying time properties. The novel aspects of our proposal consist of three main points. First, the temporal object model stands as a pivot model, and all the more leverages interoperability between software applications, since it extends common standards, such as ISO 19108 and iCalendar. Second, we accompany the object model with a formal grammar close to natural languages, which helps end users in managing and checking temporal object instances. Finally, our proposal focuses on intensional temporal expressions instead of extensional sets of concrete calendar dates. This allows to express semantic aspects – namely for periodic (cyclic) events – which remain hidden and not computable when only a series of dates are given. We evoke two kinds of applications for which our model is beneficial; one concerns services called by human users and the other addresses calls placed by software agents e.g. in a multi-agent system for instance within a simulation context.