Numerous applications need to model human activities and continuously monitor a body of data for the occurrence of such activities. Data to be monitored might include video streams from surveillance cameras, and logs generated by web applications, transaction processing systems, and intrusion detection systems. Applications might require activity detection to be performed either in real-time, as data is being received, or offline, after a body of data has been acquired. Activities tend to be high-level and can often be executed in many different ways. My research is aimed at developing techniques and algorithms to formally describe what the activities of interest are and identify occurrences of them from a body of data, both online and offline.

T-REX is a generic, domain-independent Information Extraction system. Differently from many traditional approaches, T-REX does not rely on domain-specific knowledge or site-specific features, but rather takes as input an RDF schema describing the information to be extracted, along with a training corpus of relevant sentences annotated with the semantic roles of their constituents. The Automatic Coding Engine augments T-REX extraction capabilities with a Prolog-based logic layer which enables the type of reasoning needed to answer more complex questions, and addresses the needs of political scientists and antropologists monitoring terrorist organizations and ethnic groups aroud the world.

There are many applications where we wish to derive a story about a particular event or person. For example, consider an application where a person is walking through an archaeological site such as Pompeii. Though a casual tourist may be satisfied with the simple title which usually marks exhibits, a person with a deeper interest may be unsatisfied. In the same vein, consider a US military soldier stationed at a checkpoint in Baghdad - he or she may want to know a person's "story" in order to make critical security decisions. As the diversity of the two previous applications shows, what goes into a story depends not only on the basic facts, but also on the specific items of interest to the listener. A story is formally defined to be a set of facts about a given subject that satisfies a "story length" constraint. An optimal story is a story that maximizes the value of an objective function measuring the goodness of a story.

The main objective of this multi-university project was the study and development of a middleware infrastructure to provide secure, reliable and continuously available access to information by fixed and mobile terminals, with applications to shared data access and multimedia content delivery. The architecture included a variety of servers and geographically distributed proxies, cooperating with each other according to a peer-to-peer paradigm, to provide multiple services, such as storage, data access and data manipulation, in a scalable and flexible way.