Success in calculus undoubtedly requires the ability to coordinate multiple representations (CMR; i.e., coordinate among graphs, equations, tables representing the same function). This presentation will describe a study in which calculus and pre-calculus high school students are presented with CMR activities involving graphs and equations, first in their standard format, and then in an enhanced...

How do people understand the pragmatics of spatial language? We propose a rational-speech act model for spatial reasoning, and apply it to the terms ‘in’ and ‘near’. We examine people’s fine-grain spatial reasoning in this domain by having them locate where an event occurred, given an utterance. Our pragmatic listener model provides a quantitative and qualitative fit to people’s inferences.

We describe an implemented technique for generating event models automatically based on qualitative reasoning and a statistical analysis of video input. Using an existing tracking program which generates labelled contours for objects in every frame, the view from a xed camera is partitioned into semantically relevant regions based on the paths followed by moving objects. The paths are indexed w...

An agent that is reasoning about the world often needs to draw (defeasible) conclusions that are not logically entailed by its (incomplete) knowledge about the world. Nonmonotonic reasoning systems can be used to model these reasoning patterns. Implementations of agents that can reason in a defeasible manner need to include an implemented nonmonotonic reasoning system. In different applications...

The interactions among the components of a biological system can be given a logical representation that is useful for reasoning about them. One of the relevant problems that may be raised in this context is finding what would explain a given behaviour of some component; in other terms, generating hypotheses that, when added to the logical theory modeling the system, imply that behaviour. Tempor...

In many application areas there is a need to represent human-like knowledge related to spatio-temporal relations among multiple moving objects. This type of knowledge is usually imprecise, vague and fuzzy, while the reasoning about spatio-temporal relations is intuitive. In this paper we present a model of fuzzy spatio-temporal knowledge representation and reasoning based on high-level Petri ne...

Over the past five years, we have implemented and applied efficient, general-purpose temporal reasoning as a substrate for building planning and scheduling systems. We have also investigated the kinds of temporal reasoning that will be most useful, and for what problems. Our results confirm that temporal reasoning is a sufficiently self-contained activity to be implemented entirely independentl...

Temporal reasoning problems occur in many application domains of Artificial Intelligence; therefore, it is important for us to develop algorithms for solving them efficiently. While some problems like Simple Temporal Problems are known to be tractable, some other problems like Disjunctive Temporal Problems are known to be NP-hard. In this paper, we provide a Linear Programming (LP) duality pers...

We introduce a temporal model for reasoning on disjunctive metric constraints on intervals and time points in temporal contexts. This temporal model is composed of a labeled temporal algebra and its reasoning algorithms. The labeled temporal algebra defines labeled disjunctive metric pointbased constraints, where each disjunct in each input disjunctive constraint is univocally associated to a l...

While temporal verification of programs is a topic with a long history, its traditional basis—semantics based on word languages—is ill-suited for modular reasoning about procedural programs. We address this issue by defining the semantics of procedural (potentially recursive) programs using languages of nested words and developing a framework for temporal reasoning around it. This generalizatio...