 ,                
                            
                    Guido Tack,                
                            
                    Daniel Harabor,                
                            
                    Philip Kilby
,                
                            
                    Guido Tack,                
                            
                    Daniel Harabor,                
                            
                    Philip Kilby                
                    
             Creative Commons Attribution 4.0 International license
                
    Creative Commons Attribution 4.0 International license
 
    Bi-objective search is a well-known algorithmic problem, concerned with finding a set of optimal solutions in a two-dimensional domain. This problem has a wide variety of applications such as planning in transport systems or optimal control in energy systems. Recently, bi-objective A*-based search (BOA*) has shown state-of-the-art performance in large networks. This paper develops a bi-directional and parallel variant of BOA*, enriched with several speed-up heuristics. Our experimental results on 1,000 benchmark cases show that our bi-directional A* algorithm for bi-objective search (BOBA*) can optimally solve all of the benchmark cases within the time limit, outperforming the state of the art BOA*, bi-objective Dijkstra and bi-directional bi-objective Dijkstra by an average runtime improvement of a factor of five over all of the benchmark instances.
@InProceedings{ahmadi_et_al:LIPIcs.ESA.2021.3,
  author =	{Ahmadi, Saman and Tack, Guido and Harabor, Daniel and Kilby, Philip},
  title =	{{Bi-Objective Search with Bi-Directional A*}},
  booktitle =	{29th Annual European Symposium on Algorithms (ESA 2021)},
  pages =	{3:1--3:15},
  series =	{Leibniz International Proceedings in Informatics (LIPIcs)},
  ISBN =	{978-3-95977-204-4},
  ISSN =	{1868-8969},
  year =	{2021},
  volume =	{204},
  editor =	{Mutzel, Petra and Pagh, Rasmus and Herman, Grzegorz},
  publisher =	{Schloss Dagstuhl -- Leibniz-Zentrum f{\"u}r Informatik},
  address =	{Dagstuhl, Germany},
  URL =		{https://drops.dagstuhl.de/entities/document/10.4230/LIPIcs.ESA.2021.3},
  URN =		{urn:nbn:de:0030-drops-145849},
  doi =		{10.4230/LIPIcs.ESA.2021.3},
  annote =	{Keywords: Bi-objective search, heuristic search, shortest path problem}
}
                     
                                                                                                            
                     
                                                                                                            
                    