Mon Jan 26 18:45:49 MET 1998
The research activity of the group in the area of Logic Programming and and Automated Reasoning began in the mid 80's with the study of variants of unification algorithms and extensions of logic programming languages with structuring constructs such as blocks and modules [21]. Later on the group became interested also in nonmonotonic reasoning, in particular in the characterization of Truth Maintenance Systems [20], in the properties of default logics [18], and in negation by failure in logic programming [22].
Most of the work was carried out within the Progetto Finalizzato CNR ``Sistemi Informatici e Calcolo Parallelo'' (1990-95), and the ESPRIT BRA Projects MEDLAR I and MEDLAR II ``Mechanising Deduction in the Logics of Practical Reasoning'' (1989-95).
During the participation in the MEDLAR project the group began working on nonclassical logics, in particular modal logic. Along this line of research we have studied extensions of logic programming language based on the use of multimodal operators, which can be interpreted as module names, agent beliefs or actions [19,2,4]. Another research which was carried out within the MEDLAR project concerns the development of an extended logic programming language with belief revision capabilities, which support hypothetical updates in presence of constraints [14,15].
In addition to the research mentioned above, the work of the group focused also on various topics related with nonmonotonic reasoning [9] and proof methods for nonclassical logics [25].
The research activity in 1997 has mainly dealt with the following topics.