tailieunhanh - Báo cáo khoa học: "Action representation for NL instructions"

The need to represent actions arises in many different areas of investigation, such as philosophy [5], semantics [10], and planning. In the first two areas, representations are generally developed without any computational concerns. The third area sees action representation mainly as functional to the more general task of reaching a certain goal: actions have often been represented by a predicate with some arguments, such as move(John, block1, room1, room2), augmented with a description of its effects and of what has to be true in the world for the action to be executable [8]. . | Action representation for NL instructions Barbara Di Eugenio Department of Computer and Information Science University of Pennsylvania Philadelphia PA dieugeni@ . 1 Introduction The need to represent actions arises in many different areas of investigation such as philosophy 5 semantics 10 and planning. In the first two areas representations are generally developed without any computational concerns. The third area sees action representation mainly as functional to the more general task of reaching a certain goal actions have often been represented by a predicate with some arguments such as move John block room rooms augmented with a description of its effects and of what has to be true in the world for the action to be executable 8 . Temporal relations between actions 1 and the generation relation 12 2 have also been explored. However if we ever want to be able to give instructions in NL to active agents such as robots and animated figures we should start looking at the characteristics of action descriptions in NL and devising formalisms that should be able to represent these characteristics at least in principle. NL action descriptions are complex and so are the inferences the agent interpreting them is expected to draw. As far as the complexity of action descriptions goes consider Ex. 1 Using a paint roller or brush apply paste to the wall starting at the ceiling line and pasting down a few feet and covering an area a few inches wider than the width of the fabric. The basic description apply paste to the wall is augmented with the instrument to be used and with direction and extent modifiers. The richness of the possible modifications argues against representing actions as predicates having a fixed number of arguments. Among the many complex inferences that an agent interpreting instructions is assumed to be able to draw one type is of particular interest to me namely the interaction between the intentional description of an action - which I ll .