Depth-limited search for real-time problem solving

Springer Science and Business Media LLC - Tập 2 - Trang 7-24 - 1990
Richard E. Korf1
1Computer Science Department, University of California, Los Angeles, Los Angeles, USA

Tóm tắt

We propose depth-limited heuristic search as a general paradigm for real-time problem solving in a dynamic environment. When combined with iterative-deepening, it provides the ability to commit to an action almost instantaneously, but allows the quality of that decision to improve as long as time is available. Once a deadline is reached, the best decision arrived at is executed. We illustrate the paradigm in three different settings, corresponding to single-agent search, two-player games, and multi-agent problem solving. First we review two-player minimax search with alpha-beta pruning. Minimax can be extended to themaxn algorithm for more than two players, which admits a much weaker form of alpha-beta pruning. Finally, we explore real-time search algorithms for single-agent problems. Minimax is specialized tominimin, which allows a very powerfulalpha pruning algorithm. In addition,real-time-A * allows backtracking while still guaranteeing a solution and making locally optimal decisions.

Tài liệu tham khảo

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