Showing papers by "Hector J. Levesque published in 1996"
TL;DR: It is shown that by using the right distribution of instances, and appropriate parameter values, it is possible to generate random formulas that are hard, that is, for which satisfiability testing is quite difficult.
304 citations
Proceedings Article•
04 Aug 1996TL;DR: This paper develops and motivate a specification within the situation calculus of conditional and iterative plans over domains that include binary sensing actions that is used to analyze the correctness of a small example plan, as well as variants that have redundant or missing sensing actions.
Abstract: Despite the existence of programs that are able to generate so-called conditional plans, there has yet to emerge a clear and general specification of what it is these programs are looking for: what exactly is a plan in this setting, and when is it correct? In this paper, we develop and motivate a specification within the situation calculus of conditional and iterative plans over domains that include binary sensing actions. The account is built on an existing theory of action which includes a solution to the frame problem, and an extension to it that handles sensing actions and the effect they have on the knowledge of a robot. Plans are taken to be programs in a new simple robot program language, and the planning task is to find a program that would be known by the robot at the outset to lead to a final situation where the goal is satisfied. This specification is used to analyze the correctness of a small example plan, as well as variants that have redundant or missing sensing actions. We also investigate whether the proposed robot program language is powerful enough to serve for any intuitively achievable goal.
221 citations
TL;DR: This work explores abduction tasks similar to that of the ATMS, but which return relatively small answers, and establishes for the first time a strong connection between computing abductive explanations and computing extensions in default logic.
42 citations
TL;DR: This work considers the use of random CNF formulas in evaluating the performance of SAT testing algorithms, and in particular the role that the phase transition phenomenon plays in this use.
39 citations
26 Aug 1996
TL;DR: A substantial multi-agent application developed in Golog is discussed: a system to support personal banking over computer networks and more details on the agent that assists the user in responding to changes in his financial situation are provided.
Abstract: Golog is a new programming language based on a theory of action in the situation calculus that can be used to develop multi-agent applications. The Golog interpreter automatically maintains an explicit model of the agent's environment on the basis of user supplied axioms about the preconditions and effects of actions and the initial state of the environment. This allows agent programs to query the state of the environment and consider the effects of various possible courses of action before deciding how to act. This paper discusses a substantial multi-agent application developed in Golog: a system to support personal banking over computer networks. We describe the overall system and provide more details on the agent that assists the user in responding to changes in his financial situation. The advantages and limitations of Golog for developing multi-agent applications are discussed and various extensions are suggested.
10 citations
01 Jan 1996
TL;DR: A solution to the execution of a plan containing conditionals by an agent with incomplete knowledge is proposed by integrating sensing actions into GOLOG, a high-level robot programming language.
Abstract: The execution of a plan containing conditionals by an agent with incomplete knowledge poses some difficult problems. In order for the conditional to be meaningful, the agent must know whether or not the condition is true at execution time. This paper proposes one solution to this problem by integrating sensing actions into GOLOG, a high-level robot programming language. At run time, the interpreter perfi)rms a small amount of planning to ensure that the agent will know whether or not a condition is true prior to the point where the test for the truth of the condition needs to be made.