Chaining protocols for video-on-demand require each client to forward the video data it receives to the next client watching the same video. We present here the first analytical investigation of standard chaining, advanced chaining, optimal chaining, expanded chaining (also known as the cooperative protocol) and accelerated chaining. Our results agree fairly well with earlier results obtained t...

Over the last few years there has been a revival of interest in the idea of least-commitment planning with a number of researchers returning to the partial-order planning approaches of UCPOP and VHPOP. In this paper we explore the potential of a forward-chaining state-based search strategy to support partial-order planning in the solution of temporal-numeric problems. Our planner, POPF, is buil...

in the light of the 2008 world development report, this paper revisits the impact of agriculture on overall economic growth, in the case of an oil producing country, using indices of intersectoral linkages. to this end, four input-output tables of iran’s economy are utilized. the results support the importance of the agricultural sector in stimulating the economic growth of iran, but also s...

The PRODIGY project is primarily concerned with the integration of planning and learning. Members of the PRODIGY research group have developed many learning algorithms for improving planning efficiency and plan quality, and for automatically acquiring knowledge about the properties of planning domains. The details of the PRODIGY planning algorithm, however, have not been described in the litera...

In this paper we present a novel rule-based approach for Runtime Verification of FLTL properties over finite but expanding traces. Our system exploits Horn clauses in implication form and relies on a forward chaining-based monitoring algorithm. This approach avoids the branching structure and exponential complexity typical of tableaux-based formulations, creating monitors with a single state an...

The work on Conceptual Modelling performed by our group at PUCRio is surveyed, covering four mutually dependent research topics. Regarding databases as a component of information systems, we extended the scope of the Entity-Relationship model, so as to encompass facts, events and agents in a three-schemata specification method employing a logic programming formalism. Next we proceeded to render...

We introduce a relevancy detection algorithm to be used in conjunction with the SATCHMO prover. The version of SATCHMO considered here is essentially a bidi-rectional prover, utilizing Prolog (back-chaining) on Horn clauses and forward-chaining on non-Horn clauses. Our extension, SATCHMORE (SATCHMO with RElevancy), addresses the major weakness of SATCHMO: the uncontrolled use of forward-chainin...