{"type":"ScholarlyArticle","title":"Forward Perimeter Search with Controlled Use of Memory","authors":[{"name":"Thorsten Schütt","slug":"thorsten-schutt","given":"Thorsten","family":"Schütt","affiliation":""},{"name":"Robert Döbbelin","slug":"robert-dobbelin","given":"Robert","family":"Döbbelin","affiliation":""},{"name":"Alexander Reinefeld","slug":"alexander-reinefeld","given":"Alexander","family":"Reinefeld","affiliation":""}],"abstract":"There are many hard shortest-path search problems that cannot be solved, because best-first search runs out of memory space and depth-first search runs out of time. We propose Forward Perimeter Search (FPS), a heuristic search with controlled use of memory. It builds a perimeter around the root node and tests each perimeter node for a shortest path to the goal. The perimeter is adaptively extended towards the goal during the search process. We show that FPS expands in random 24-puzzles 50% fewer nodes than BF-IDA* while requiring several orders of magnitude less memory. Additionally, we present a hard problem instance of the 24-puzzle that needs at least 140 moves to solve; i.e. 26 more moves than the previously published hardest instance.","doi":null,"url":"https://ijcai.org/proceedings/2013/104","pdf":"https://ijcai.org/proceedings/2013/0104.pdf","markdown":"https://ijcai.org/proceedings/2013/104.md","bibtex":"https://ijcai.org/proceedings/2013/bibtex/104","volume":{"slug":"2013","title":"Proceedings of the Twenty-Third International Joint Conference on Artificial Intelligence","short_title":"IJCAI 2013","url":"https://ijcai.org/proceedings/2013/","year":2013,"location":"Beijing, China","dates":"3–9 August 2013","editors":"Francesca Rossi","isbn":"978-1-57735-633-2","publisher":"AAAI Press / International Joint Conferences on Artificial Intelligence","doi_prefix":""},"section":null,"track":"","number":104,"pages":{"first":659,"last":664},"keywords":[],"videos":[],"references":[],"license_note":"Copyright International Joint Conferences on Artificial Intelligence."}