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Sequential

Domain

Authors

Remarks

Crisp

Ron Petrick and Alexander Koller

Required conditional-effects and quantified-preconditions which were not supported by most of participant planners

Market

Amanda Coles and Andrew Coles

Required numeric preconditions which were not supported by most of participant planners

Contingent Domains

Guy Shani

A collection of contingent planning domains compiled into classical planning. Required conditional-effects and quantified-preconditions which were not supported by most of participant planners

Temporal

Domain

Authors

Remarks

Cooking

Frédéric Maris

Most planners did not support the domain representation

Crisp

From the attached paper: "In general, the problem of deciding whether a given communicative goal can be achieved with a given grammar is NP-complete (Koller and Striegnitz 2002): a naïve search algorithm that computes a derivation top-down takes exponential time. The parameters d, m, and n allow us to scale various linguistic dimensions of the problem freely. An increase in each parameter increases both the minimal plan length and the number of objects in the universe; both are O(dmn). Note that the size of the search space grows exponentially both in d and in m, because the grammar allows us to express each noun phrase in many different ways. Before the use of planning was proposed for this specific type of sentence generation problem, the state of the art in the NLG literature was to use greedy search to circumvent the combinatorial explosion (e.g., in the seminal SPUD system (Stone et al. 2003)). This is an incomplete search strategy which can make systems based on it unusable in practice. Using planning for the problem carries the promise of achieving complete search at reasonable efficiency, by employing modern search heuristics for planning, and ties in with the significant body of literature focused on using planning for other subproblems of NLG."

Market

"One slight snag with this domain, the problem files are generated from the game Elite, and we are seeking permission to be allowed to distribute these (the authors of the game have fallen out and are no longer speaking, we have permission from one so far but are awaiting the other). So please don't distribute these problems any further until we get this permission. If permission fails to materialise the domain is our creation, so we can generate some more free-to-use problems to go with it."

Cooking

The "cooking" domain allows us to plan the preparation of a meal, as well as its consumption by respecting constraints of warmth. Problems cooking-carbonara-n allow us to plan the preparation of n dishes of pasta. The concurrency of actions is required to obtain the goal because it is necessary that the electrical plates works so that water and oil are hot enough to cook pasta and bacon cubes. It is also necessary to perform this baking in parallel to serve a hot dish during its consumption. We have defined too the "cooking-pddl2.1" version of this domain for temporally-expressive planners which do not support richer durative actions (that is with time intervals), where the actions are split into several sub-actions without time interval.

All possible solutions require concurrency of actions (temporally expressive problem).

Although many temporal planners have been compared in the International Planning Competitions (IPC), recent theoretical studies have brought to light the limitations of the current approaches to temporal planning [1]. [2] shows that the domains and problems which have been used up until now in the last competitions can always be solved with a sequential plan. They propose a method to prove that a domain can only be solved using concurrent actions. In fact, the winning planners in the IPC competitions, even if they are efficient in a restricted temporal framework, cannot solve problems for which all possible solutions require parallelism (temporally expressive problems) but only those for which there is at least a sequential solution (temporally simple problems). So, they are therefore far from being capable of solving real-world problems. The objective evaluation of these systems requires the setting up of new benchmarks corresponding to temporally expressive problems.

References:

[1] W.Cushing, S.Kambhampati, Mausam, D.S.Weld, "When is temporal planning really temporal ?", IJCAI, pp. 1852-1859, 2007.

[2] W.Cushing, S.Kambhampati, K.Talamadupula, D.S.Weld, Mausam, "Evaluating temporal planning domains", ICAPS, pp. 105-112, 2007.

[3] Maris F., Régnier P., 2008, "TLP-GP: New Results on Temporally-Expressive Planning Benchmarks", in Proceedings of 20th IEEE International Conference on Tools with Artificial Intelligence (ICTAI-2008), vol. 1, pp 507-514, Dayton OH, USA, November 2008.

[4] Maris F., Régnier P., 2008, "TLP-GP: Solving Temporally-Expressive Planning Problems", in Proceedings of 15th International Symposium on Temporal Representation and Reasoning (TIME-2008), pp 137-144, Montreal QC, Canada, June 2008.


2013-10-04 16:34