ECAI '92 Proceedings of the 10th European conference on Artificial intelligence
Automatically synthesising domain constraints from operator descriptions
ECAI '92 Proceedings of the 10th European conference on Artificial intelligence
Temporal planning with continuous change
AAAI'94 Proceedings of the twelfth national conference on Artificial intelligence (vol. 2)
Fast planning through planning graph analysis
Artificial Intelligence
Engineering and compiling planning domain models to promote validity and efficiency
Artificial Intelligence
State-variable planning under structural restrictions: algorithms and complexity
Artificial Intelligence
Inferring state constraints for domain-independent planning
AAAI '98/IAAI '98 Proceedings of the fifteenth national/tenth conference on Artificial intelligence/Innovative applications of artificial intelligence
CPlan: a constraint programming approach to planning
AAAI '99/IAAI '99 Proceedings of the sixteenth national conference on Artificial intelligence and the eleventh Innovative applications of artificial intelligence conference innovative applications of artificial intelligence
Artificial Intelligence - Special issue on heuristic search in artificial intelligence
Unifying SAT-based and Graph-based Planning
IJCAI '99 Proceedings of the Sixteenth International Joint Conference on Artificial Intelligence
Branching and pruning: an optimal temporal POCL planner based on constraint programming
Artificial Intelligence
Planning as satisfiability: parallel plans and algorithms for plan search
Artificial Intelligence
PDDL2.1: an extension to PDDL for expressing temporal planning domains
Journal of Artificial Intelligence Research
Planning through stochastic local search and temporal action graphs in LPG
Journal of Artificial Intelligence Research
The automatic inference of state invariants in TIM
Journal of Artificial Intelligence Research
Long-distance mutual exclusion for propositional planning
IJCAI'07 Proceedings of the 20th international joint conference on Artifical intelligence
Friends or foes? on planning as satisfiability and abstract CNF encodings
Journal of Artificial Intelligence Research
SAS+ planning as satisfiability
Journal of Artificial Intelligence Research
On the utility of landmarks in SAT based planning
Knowledge-Based Systems
Planning as satisfiability with IPC simple preferences and action costs
AI Communications
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Mutual exclusion (mutex) is a powerful mechanism for search space pruning in planning. However, a serious limitation of mutex is that it cannot specify constraints relating actions and facts across different time steps. In this paper, we propose a new class of mutual exclusions that significantly generalizes mutex and can be efficiently computed. The proposed long-distance mutual exclusion (londex) can capture constraints over actions and facts not only at the same time step but also across multiple steps. As a generalization, londex is much stronger than mutex, and provides a general and effective tool for developing efficient planners. We propose two levels of londex. The first level, londex"1, is derived from individual domain transition graphs (DTGs), and the second level, londex"m, is derived from multiple DTGs by taking into account the interactions among them. Londex constraints provide stronger pruning power but also require a large amount of memory. To address the memory problem, we further develop a virtual realization mechanism in which only a small proportion of londex constraints are dynamically generated as needed during the search. This scheme can save a huge amount of memory without sacrificing the pruning power of londex. For evaluation purposes, we incorporate londex into SATPlan04 and SATPlan06, two efficient SAT-based planners. Our experimental results show that londex"m can significantly improve over londex"1 since the former exploits causal dependencies among DTGs. Our experimental results for various planning domains also show significant advantages of using londex constraints for reducing planning time.