{"type":"ScholarlyArticle","title":"A Survey on Hierarchical Planning – One Abstract Idea, Many Concrete Realizations","authors":[{"name":"Pascal Bercher","slug":"pascal-bercher","given":"Pascal","family":"Bercher","affiliation":"Institute of Artificial Intelligence , Ulm University , Germany"},{"name":"Ron Alford","slug":"ron-alford","given":"Ron","family":"Alford","affiliation":"MITRE , McLean , Virginia , USA"},{"name":"Daniel Höller","slug":"daniel-holler","given":"Daniel","family":"Höller","affiliation":"Institute of Artificial Intelligence , Ulm University , Germany"}],"abstract":"Hierarchical planning has attracted renewed interest in the last couple of years, which led to numerous novel formalisms, problem classes, and theoretical investigations. Yet it is important to differentiate between the various formalisms and problem classes, since they show -- sometimes fundamental -- differences with regard to their expressivity and computational complexity: Some of them can be regarded equivalent to non-hierarchical formalisms while others are clearly more expressive. We survey the most important hierarchical problem classes and explain their differences and similarities. We furthermore give pointers to some of the best-known planning systems capable of solving the respective problem classes.","doi":"10.24963/ijcai.2019/875","url":"https://ijcai.org/proceedings/2019/875","pdf":"https://ijcai.org/proceedings/2019/0875.pdf","markdown":"https://ijcai.org/proceedings/2019/875.md","bibtex":"https://ijcai.org/proceedings/2019/bibtex/875","volume":{"slug":"2019","title":"Proceedings of the Twenty-Eighth International Joint Conference on Artificial Intelligence","short_title":"IJCAI 2019","url":"https://ijcai.org/proceedings/2019/","year":2019,"location":"Macao","dates":"10-16 August 2019","editors":"Sarit Kraus","isbn":"978-0-9992411-4-1","publisher":"International Joint Conferences on Artificial Intelligence Organization","doi_prefix":"10.24963/ijcai.2019"},"section":"Survey track","track":"Survey track","number":875,"pages":{"first":6267,"last":6275},"keywords":["Planning and Scheduling: Planning Algorithms","Planning and Scheduling: Theoretical Foundations of Planning","Planning and Scheduling: Hierarchical planning","Planning and Scheduling: Search in Planning and Scheduling"],"videos":[],"references":[{"position":1,"raw":"[Alford et al., 2009] Ron Alford, Ugur Kuter, and Dana S. Nau. Translating HTNs to PDDL: A small amount of do- main knowledge can go a long way. In IJCAI, pages 1629- 1634. AAAI Press, 2009.","title":"Translating HTNs to PDDL: A small amount of domain knowledge can go a long way","authors":"Ron Alford, Ugur Kuter, Dana S Nau","year":"2009","venue":"IJCAI","doi":null,"url":null,"internal_url":"/proceedings/2009/272"},{"position":2,"raw":"[Alford et al., 2012] Ron Alford, Vikas Shivashankar, Ugur Kuter, and Dana Nau. HTN problem spaces: Structure, algorithms, termination. In SoCS, pages 2-9. AAAI Press, 2012.","title":"HTN problem spaces: Structure, algorithms, termination","authors":"Ron Alford, Vikas Shivashankar, Ugur Kuter, Dana Nau","year":"2012","venue":"SoCS","doi":null,"url":null,"internal_url":null},{"position":3,"raw":"[Alford et al., 2014] Ron Alford, Vikas Shivashankar, Ugur Kuter, and Dana Nau. On the feasibility of planning graph style heuristics for HTN planning. In ICAPS, pages 2-10. AAAI Press, 2014.","title":"On the feasibility of planning graph style heuristics for HTN planning","authors":"Ron Alford, Vikas Shivashankar, Ugur Kuter, Dana Nau","year":"2014","venue":"ICAPS","doi":null,"url":null,"internal_url":null},{"position":4,"raw":"[Alford et al., 2015a] Ron Alford, Pascal Bercher, and David Aha. Tight bounds for HTN planning. In ICAPS, pages 7- 15. AAAI Press, 2015.","title":"Tight bounds for HTN planning","authors":"Alford","year":"2015","venue":"ICAPS","doi":null,"url":null,"internal_url":null},{"position":5,"raw":"[Alford et al., 2015b] Ron Alford, Pascal Bercher, and David Aha. Tight bounds for HTN planning with task in- sertion. In IJCAI, pages 1502-1508. AAAI Press, 2015.","title":"Tight bounds for HTN planning with task insertion","authors":"Alford","year":"2015","venue":"IJCAI","doi":null,"url":null,"internal_url":"/proceedings/2015/215"},{"position":6,"raw":"[Alford et al., 2016a] Ron Alford, Gregor Behnke, Daniel Höller, Pascal Bercher, Susanne Biundo, and David Aha. Bound to plan: Exploiting classical heuristics via auto- matic translations of tail-recursive HTN problems. In ICAPS, pages 20-28. AAAI Press, 2016.","title":"Bound to plan: Exploiting classical heuristics via automatic translations of tail-recursive HTN problems","authors":"Alford","year":"2016","venue":"ICAPS","doi":null,"url":null,"internal_url":null},{"position":7,"raw":"[Alford et al., 2016b] Ron Alford, Vikas Shivashankar, Mark Roberts, Jeremy Frank, and David W. Aha. Hier- archical planning: Relating task and goal decomposition with task sharing. In IJCAI, pages 3022-3029. AAAI Press, 2016.","title":"Hierarchical planning: Relating task and goal decomposition with task sharing","authors":"Alford","year":"2016","venue":"IJCAI","doi":null,"url":null,"internal_url":"/proceedings/2016/429"},{"position":8,"raw":"[Barták and Dvorák, 2016] Roman Barták and Tomás Dvorák. On verification of workflow and planning domain models using attribute grammars. In Proc. of the 15th Mexican Int. Conf. on AI (MICAI), pages 332-345.","title":"Roman Barták and Tomás Dvorák. On verification of workflow and planning domain models using attribute grammars","authors":"Dvorák Barták","year":"2016","venue":"Proc. of the 15th Mexican Int. Conf. on AI (MICAI)","doi":null,"url":null,"internal_url":null},{"position":9,"raw":"[Barták and Vlk, 2016] Roman Barták and Marek Vlk. Hi- erarchical task model for resource failure recovery in pro- duction scheduling. In Proc. of the 15th Mexican Int. Conf. on AI (MICAI), pages 362-378. Springer, 2016.","title":"Roman Barták and Marek Vlk. Hierarchical task model for resource failure recovery in production scheduling","authors":"Vlk Barták","year":"2016","venue":"Proc. of the 15th Mexican Int. Conf. on AI (MICAI)","doi":null,"url":null,"internal_url":null},{"position":10,"raw":"[Beetz et al., 2012] Michael Beetz, Dominik Jain, Lorenz Mösenlechner, Moritz Tenorth, Lars Kunze, Nico Blodow, and Dejan Pangercic. Cognition-enabled autonomous robot control for the realization of home chore task intelli- gence. Proc. of the IEEE, 100(8):2454-2471, 2012.","title":"Cognition-enabled autonomous robot control for the realization of home chore task intelligence","authors":"Michael Beetz, Dominik Jain, Lorenz Mösenlechner, Moritz Tenorth, Lars Kunze, Nico Blodow, Dejan Pangercic","year":"2012","venue":"Proc. of the IEEE","doi":null,"url":null,"internal_url":null},{"position":11,"raw":"[Behnke et al., 2016] Gregor Behnke, Daniel Höller, Pascal Bercher, and Susanne Biundo. Change the plan -How hard can that be? In ICAPS, pages 38-46. AAAI Press, 2016.","title":"Change the plan -How hard can that be?","authors":"Gregor Behnke, Daniel Höller, Pascal Bercher, Susanne Biundo","year":"2016","venue":"ICAPS","doi":null,"url":null,"internal_url":null},{"position":12,"raw":"[Behnke et al., 2018] Gregor Behnke, Daniel Höller, and Su- sanne Biundo. totSAT -Totally-ordered hierarchical plan- ning through SAT. In AAAI, pages 6110-6118. AAAI Press, 2018.","title":"totSAT -Totally-ordered hierarchical planning through SAT","authors":"Gregor Behnke, Daniel Höller, Susanne Biundo","year":"2018","venue":"AAAI","doi":null,"url":null,"internal_url":null},{"position":13,"raw":"[Behnke et al., 2019a] Gregor Behnke, Daniel Höller, and Susanne Biundo. Finding optimal solutions in HTN plan- ning -A SAT-based approach. In IJCAI. IJCAI, 2019.","title":"Finding optimal solutions in HTN planning -A SAT-based approach","authors":"Behnke","year":"2019","venue":"IJCAI. IJCAI","doi":null,"url":null,"internal_url":"/proceedings/2019/764"},{"position":14,"raw":"[Behnke et al., 2019b] Gregor Behnke, Marvin Schiller, Matthias Kraus, Pascal Bercher, Mario Schmautz, Michael Dorna, Michael Dambier, Wolfgang Minker, Birte Glimm, and Susanne Biundo. Alice in DIY wonderland or: In- structing novice users on how to use tools in DIY projects. AI Communications, 32:31-57, 2019.","title":"Alice in DIY wonderland or: Instructing novice users on how to use tools in DIY projects","authors":"Behnke","year":"2019","venue":"AI Communications","doi":null,"url":null,"internal_url":null},{"position":15,"raw":"[Bercher et al., 2014a] Pascal Bercher, Susanne Biundo, Thomas Geier, Thilo Hörnle, Florian Nothdurft, Felix Richter, and Bernd Schattenberg. Plan, repair, execute, explain -How planning helps to assemble your home the- ater. In ICAPS, pages 386-394. AAAI Press, 2014.","title":"Plan, repair, execute, explain -How planning helps to assemble your home theater","authors":"Bercher","year":"2014","venue":"ICAPS","doi":null,"url":null,"internal_url":null},{"position":16,"raw":"[Bercher et al., 2014b] Pascal Bercher, Shawn Keen, and Su- sanne Biundo. Hybrid planning heuristics based on task decomposition graphs. In SoCS, pages 35-43. AAAI Press, 2014.","title":"Hybrid planning heuristics based on task decomposition graphs","authors":"Bercher","year":"2014","venue":"SoCS","doi":null,"url":null,"internal_url":null},{"position":17,"raw":"[Bercher et al., 2016] Pascal Bercher, Daniel Höller, Gregor Behnke, and Susanne Biundo. More than a name? On im- plications of preconditions and effects of compound HTN planning tasks. In ECAI, pages 225-233. IOS Press, 2016.","title":"More than a name? On implications of preconditions and effects of compound HTN planning tasks","authors":"Pascal Bercher, Daniel Höller, Gregor Behnke, Susanne Biundo","year":"2016","venue":"ECAI","doi":null,"url":null,"internal_url":null},{"position":18,"raw":"[Bercher et al., 2017] Pascal Bercher, Gregor Behnke, Daniel Höller, and Susanne Biundo. An admissible HTN planning heuristic. In IJCAI, pages 480-488. IJCAI, 2017.","title":"An admissible HTN planning heuristic","authors":"Pascal Bercher, Gregor Behnke, Daniel Höller, Susanne Biundo","year":"2017","venue":"IJCAI","doi":null,"url":null,"internal_url":"/proceedings/2017/68"},{"position":19,"raw":"[Bit-Monnot et al., 2016] Arthur Bit-Monnot, David E. Smith, and Minh Do. Delete-free reachability analysis for temporal and hierarchical planning. In ECAI, pages 1698- 1699. IOS Press, 2016.","title":"Delete-free reachability analysis for temporal and hierarchical planning","authors":"Arthur Bit-Monnot, David E Smith, Minh Do","year":"2016","venue":"ECAI","doi":null,"url":null,"internal_url":null},{"position":20,"raw":"[Biundo and Schattenberg, 2001] Susanne Biundo and Bernd Schattenberg. From abstract crisis to concrete relief -A preliminary report on combining state abstraction and HTN planning. In ECP, pages 157-168. AAAI Press, 2001.","title":"From abstract crisis to concrete relief -A preliminary report on combining state abstraction and HTN planning","authors":"Susanne Biundo, Bernd Schattenberg","year":"2001","venue":"ECP","doi":null,"url":null,"internal_url":null},{"position":21,"raw":"[Bresina et al., 2005] John L. Bresina, Ari K. Jónsson, Paul H. Morris, and Kanna Rajan. Activity planning for the mars exploration rovers. In ICAPS, pages 40-49. AAAI Press, 2005.","title":"Activity planning for the mars exploration rovers","authors":"John L Bresina, Ari K Jónsson, Paul H Morris, Kanna Rajan","year":"2005","venue":"ICAPS","doi":null,"url":null,"internal_url":null},{"position":22,"raw":"[de Silva et al., 2019] Lavindra de Silva, Lin Padgham, and Sebastian Sardina. HTN-like solutions for classical plan- ning problems: An application to BDI agent systems. The- oretical Computer Science, 763:12-37, 2019.","title":"Lavindra de Silva, Lin Padgham, and Sebastian Sardina. HTN-like solutions for classical plan-ning problems: An application to BDI agent systems","authors":"Silva De","year":"2019","venue":"Theoretical Computer Science","doi":null,"url":null,"internal_url":null},{"position":23,"raw":"[Dix et al., 2003] Jürgen Dix, Ugur Kuter, and Dana Nau. Planning in answer set programming using ordered task decomposition. In Proc. of the 26th German Conf. on AI (KI), pages 490-504. Springer, 2003.","title":"Planning in answer set programming using ordered task decomposition","authors":"Jürgen Dix, Ugur Kuter, Dana Nau","year":"2003","venue":"Proc. of the 26th German Conf. on AI (KI)","doi":null,"url":null,"internal_url":null},{"position":24,"raw":"[Dvoȓák et al., 2014] Filip Dvoȓák, Roman Barták, Arthur Bit-Monnot, Félix Ingrand, and Malik Ghallab. Planning and acting with temporal and hierarchical decomposition models. In ICTAI, pages 115-121. IEEE, 2014.","title":"Planning and acting with temporal and hierarchical decomposition models","authors":"Filip Dvoȓák, Roman Barták, Arthur Bit-Monnot, Félix Ingrand, Malik Ghallab","year":"2014","venue":"ICTAI","doi":null,"url":null,"internal_url":null},{"position":25,"raw":"[Erol et al., 1994] Kutluhan Erol, James Hendler, and Dana S. Nau. UMCP: A sound and complete procedure for hierarchical task-network planning. In AIPS, pages 249- 254. AAAI Press, 1994.","title":"UMCP: A sound and complete procedure for hierarchical task-network planning","authors":"Erol","year":"1994","venue":"AIPS","doi":null,"url":null,"internal_url":null},{"position":26,"raw":"[Erol et al., 1996] Kutluhan Erol, James A. Hendler, and Dana S. Nau. Complexity results for HTN planning. An- nals of Mathematics and AI (AMAI), 18(1):69-93, 1996.","title":"Complexity results for HTN planning","authors":"Erol","year":"1996","venue":"Annals of Mathematics and AI","doi":null,"url":null,"internal_url":null},{"position":27,"raw":"[Fox and Long, 2006] Maria Fox and Derek Long. Mod- elling mixed discrete-continuous domains for planning. Journal of AI Research (JAIR), 27(1):235-297, 2006.","title":"Modelling mixed discrete-continuous domains for planning","authors":"Maria Fox, Derek Long","year":"2006","venue":"Journal of AI Research (JAIR)","doi":null,"url":null,"internal_url":null},{"position":28,"raw":"[Fox, 1997] Maria Fox. Natural hierarchical planning us- ing operator decomposition. In ECP, pages 195-207. Springer, 1997.","title":"Natural hierarchical planning using operator decomposition","authors":"Maria Fox","year":"1997","venue":"ECP","doi":null,"url":null,"internal_url":null},{"position":29,"raw":"[Geib, 2004] Christopher W. Geib. Assessing the complexity of plan recognition. In AAAI, pages 507-512. AAAI Press, 2004.","title":"Assessing the complexity of plan recognition","authors":"Christopher W Geib","year":"2004","venue":"AAAI","doi":null,"url":null,"internal_url":null},{"position":30,"raw":"[Geier and Bercher, 2011] Thomas Geier and Pascal Bercher. On the decidability of HTN planning with task insertion. In IJCAI, pages 1955-1961. AAAI Press, 2011.","title":"On the decidability of HTN planning with task insertion","authors":"Bercher Geier, Thomas Geier, Pascal Bercher","year":"2011","venue":"IJCAI","doi":null,"url":null,"internal_url":"/proceedings/2011/327"},{"position":31,"raw":"[Georgievski and Aiello, 2015] Ilche Georgievski and Marco Aiello. HTN planning: Overview, comparison, and beyond. Artificial Intelligence, 222(0):124-156, 2015.","title":"Ilche Georgievski and Marco Aiello. HTN planning: Overview, comparison, and beyond","authors":"Aiello Georgievski","year":"2015","venue":"Artificial Intelligence","doi":null,"url":null,"internal_url":null},{"position":32,"raw":"[Gerevini et al., 2008] Alfonso Gerevini, Ugur Kuter, Dana S. Nau, Alessandro Saetti, and Nathaniel Waisbrot. Combining domain-independent planning and HTN planning: The Duet planner. In ECAI, pages 573-577. IOS Press, 2008.","title":"Combining domain-independent planning and HTN planning: The Duet planner","authors":"Alfonso Gerevini, Ugur Kuter, Dana S Nau, Alessandro Saetti, Nathaniel Waisbrot","year":"2008","venue":"ECAI","doi":null,"url":null,"internal_url":null},{"position":33,"raw":"[Ghallab et al., 2004] Malik Ghallab, Dana S. Nau, and Paolo Traverso. Automated Planning: Theory and Prac- tice. Morgan Kaufmann, 2004.","title":"Automated Planning: Theory and Practice","authors":"Malik Ghallab, Dana S Nau, Paolo Traverso","year":"2004","venue":null,"doi":null,"url":null,"internal_url":null},{"position":34,"raw":"[Goldman and Kuter, 2019] Robert P. Goldman and Ugur Kuter. Hierarchical task network planning in common Lisp: The case of SHOP3. In Proc. of the 12th Europ. Lisp Symp. (ELS), pages 73-80. ACM, 2019.","title":"Hierarchical task network planning in common Lisp: The case of SHOP3","authors":"Robert P Goldman, Ugur Kuter","year":"2019","venue":"Proc. of the 12th Europ. Lisp Symp. (ELS)","doi":null,"url":null,"internal_url":null},{"position":35,"raw":"[Goldman, 2009] Robert Goldman. A semantics for HTN methods. In ICAPS, pages 146-153. AAAI Press, 2009.","title":"A semantics for HTN methods","authors":"Robert Goldman","year":"2009","venue":"ICAPS","doi":null,"url":null,"internal_url":null},{"position":36,"raw":"[González et al., 2017] José Carlos González, José Carlos Pulido, and Fernando Fernández. A three-layer planning architecture for the autonomous control of rehabilitation therapies based on social robots. Cognitive Systems Re- search, 43(Supplement C):232-249, 2017.","title":"José Carlos González, José Carlos Pulido, and Fernando Fernández. A three-layer planning architecture for the autonomous control of rehabilitation therapies based on social robots","authors":"González","year":"2017","venue":"Cognitive Systems Research","doi":null,"url":null,"internal_url":null},{"position":37,"raw":"[Höller et al., 2014] Daniel Höller, Gregor Behnke, Pascal Bercher, and Susanne Biundo. Language classification of hierarchical planning problems. In ECAI, pages 447-452.","title":"Language classification of hierarchical planning problems","authors":"Daniel Höller, Gregor Behnke, Pascal Bercher, Susanne Biundo","year":null,"venue":"ECAI","doi":null,"url":null,"internal_url":null},{"position":38,"raw":"[Höller et al., 2016] Daniel Höller, Gregor Behnke, Pascal Bercher, and Susanne Biundo. Assessing the expressivity of planning formalisms through the comparison to formal languages. In ICAPS, pages 158-165. AAAI Press, 2016.","title":"Assessing the expressivity of planning formalisms through the comparison to formal languages","authors":"Daniel Höller, Gregor Behnke, Pascal Bercher, Susanne Biundo","year":"2016","venue":"ICAPS","doi":null,"url":null,"internal_url":null},{"position":39,"raw":"[Höller et al., 2018a] Daniel Höller, Gregor Behnke, Pascal Bercher, and Susanne Biundo. Plan and goal recognition as HTN planning. In ICTAI, pages 466-473. IEEE, 2018.","title":"Plan and goal recognition as HTN planning","authors":"Höller","year":"2018","venue":"ICTAI","doi":null,"url":null,"internal_url":null},{"position":40,"raw":"[Höller et al., 2018b] Daniel Höller, Pascal Bercher, Gre- gor Behnke, and Susanne Biundo. A generic method to guide HTN progression search with classical heuristics. In ICAPS, pages 114-122. AAAI Press, 2018.","title":"A generic method to guide HTN progression search with classical heuristics","authors":"Höller","year":"2018","venue":"ICAPS","doi":null,"url":null,"internal_url":null},{"position":41,"raw":"[Höller et al., 2019a] Daniel Höller, Gregor Behnke, Pascal Bercher, Susanne Biundo, Humbert Fiorino, Damien Pel- lier, and Ron Alford. HDDL -A language to describe hi- erarchical planning problems. In Proc. of the 2nd ICAPS Workshop on Hierarchical Planning, pages 6-14, 2019.","title":"HDDL -A language to describe hierarchical planning problems","authors":"Höller","year":"2019","venue":"Proc. of the 2nd ICAPS Workshop on Hierarchical Planning","doi":null,"url":null,"internal_url":null},{"position":42,"raw":"[Höller et al., 2019b] Daniel Höller, Pascal Bercher, Gregor Behnke, and Susanne Biundo. On guiding search in HTN planning with classical planning heuristics. In IJCAI. IJ- CAI, 2019.","title":"On guiding search in HTN planning with classical planning heuristics","authors":"Höller","year":"2019","venue":"IJCAI. IJ-CAI","doi":null,"url":null,"internal_url":"/proceedings/2019/857"},{"position":43,"raw":"[Kambhampati et al., 1998] Subbarao Kambhampati, Amol Mali, and Biplav Srivastava. Hybrid planning for partially hierarchical domains. In AAAI, pages 882-888. AAAI Press, 1998.","title":"Hybrid planning for partially hierarchical domains","authors":"Subbarao Kambhampati, Amol Mali, Biplav Srivastava","year":"1998","venue":"AAAI","doi":null,"url":null,"internal_url":null},{"position":44,"raw":"[Mali and Kambhampati, 1998] Amol D. Mali and Subbarao Kambhampati. Encoding HTN planning in propositional logic. In AIPS, pages 190-198. AAAI Press, 1998.","title":"Encoding HTN planning in propositional logic","authors":"D Amol, Subbarao Mali, Kambhampati","year":"1998","venue":"AIPS","doi":null,"url":null,"internal_url":null},{"position":45,"raw":"[Marthi et al., 2007] Bhaskara Marthi, Stuart J. Russell, and Jason Wolfe. Angelic semantics for high-level actions. In ICAPS 2007, pages 232-239. AAAI Press, 2007.","title":"Angelic semantics for high-level actions","authors":"Bhaskara Marthi, Stuart J Russell, Jason Wolfe","year":"2007","venue":"ICAPS 2007","doi":null,"url":null,"internal_url":null},{"position":46,"raw":"[Marthi et al., 2008] Bhaskara Marthi, Stuart Russell, and Jason Wolfe. Angelic hierarchical planning: Optimal and online algorithms. In ICAPS, pages 222-231. AAAI Press, 2008.","title":"Angelic hierarchical planning: Optimal and online algorithms","authors":"Bhaskara Marthi, Stuart Russell, Jason Wolfe","year":"2008","venue":"ICAPS","doi":null,"url":null,"internal_url":null},{"position":47,"raw":"[McDermott, 2000] Drew V. McDermott. The 1998 AI plan- ning systems competition. AI Magazine, 21(2):35-55, 2000.","title":"The 1998 AI planning systems competition","authors":"V Drew, Mcdermott","year":"2000","venue":"AI Magazine","doi":null,"url":null,"internal_url":null},{"position":48,"raw":"[Molineaux et al., 2010] Matthew Molineaux, Matthew Klenk, and David Aha. Planning in dynamic envi- ronments: Extending HTNs with nonlinear continuous effects. In AAAI, pages 1115-1120. AAAI Press, 2010.","title":"Planning in dynamic environments: Extending HTNs with nonlinear continuous effects","authors":"Matthew Molineaux, Matthew Klenk, David Aha","year":"2010","venue":"AAAI","doi":null,"url":null,"internal_url":null},{"position":49,"raw":"[Nau et al., 2001] Dana S. Nau, Yue Cao, Amnon Lotem, and Héctor Muñoz-Avila. The SHOP planning system. AI Magazine, 22(3):91-94, 2001.","title":"The SHOP planning system","authors":"Dana S Nau, Yue Cao, Amnon Lotem, Héctor Muñoz-Avila","year":"2001","venue":"AI Magazine","doi":null,"url":null,"internal_url":null},{"position":50,"raw":"[Nau et al., 2003] Dana Nau, Tsz-Chiu Au, Okhtay Ilghami, Ugur Kuter, J. William Murdock, Dan Wu, and Fusun Ya- man. SHOP2: An HTN planning system. Journal of AI Research (JAIR), 20:379-404, 2003.","title":"SHOP2: An HTN planning system","authors":"Dana Nau, Tsz-Chiu Au, Okhtay Ilghami, Ugur Kuter, J William Murdock, Dan Wu, Fusun Yaman","year":"2003","venue":"Journal of AI Research (JAIR)","doi":null,"url":null,"internal_url":null},{"position":51,"raw":"[Nau et al., 2005] Dana S. Nau, Tsz-Chiu Au, Okhtay Il- ghami, Ugur Kuter, Dan Wu, Fusun Yaman, Héctor Muñoz-Avila, and J. William Murdock. Applications of SHOP and SHOP2. Intelligent Systems, IEEE, 20:34-41, 2005.","title":"Applications of SHOP and SHOP2. Intelligent Systems","authors":"Dana S Nau, Tsz-Chiu Au, Okhtay Ilghami, Ugur Kuter, Dan Wu, Fusun Yaman, Héctor Muñoz-Avila, J William Murdock","year":"2005","venue":"IEEE","doi":null,"url":null,"internal_url":null},{"position":52,"raw":"[Nau, 2007] Dana S. Nau. Current trends in automated plan- ning. AI Magazine, 28(4):43-58, 2007.","title":"Current trends in automated planning","authors":"Dana S Nau","year":"2007","venue":"AI Magazine","doi":null,"url":null,"internal_url":null},{"position":53,"raw":"[Schreiber et al., 2019] Dominik Schreiber, Tomáš Balyo, Damien Pellier, and Humbert Fiorino. Tree-REX: SAT- based tree exploration for efficient and high-quality HTN planning. In ICAPS. AAAI Press, 2019.","title":"Tree-REX: SATbased tree exploration for efficient and high-quality HTN planning","authors":"Dominik Schreiber, Tomáš Balyo, Damien Pellier, Humbert Fiorino","year":"2019","venue":"ICAPS","doi":null,"url":null,"internal_url":null},{"position":54,"raw":"[Seegebarth et al., 2012] Bastian Seegebarth, Felix Müller, Bernd Schattenberg, and Susanne Biundo. Making hybrid plans more clear to human users -A formal approach for generating sound explanations. In ICAPS, pages 225-233. AAAI Press, 2012.","title":"Making hybrid plans more clear to human users -A formal approach for generating sound explanations","authors":"Bastian Seegebarth, Felix Müller, Bernd Schattenberg, Susanne Biundo","year":"2012","venue":"ICAPS","doi":null,"url":null,"internal_url":null},{"position":55,"raw":"[Shivashankar et al., 2012] Vikas Shivashankar, Ugur Kuter, Dana Nau, and Ron Alford. A hierarchical goal-based for- malism and algorithm for single-agent planning. In AA- MAS, pages 981-988. IFAAMAS, 2012.","title":"A hierarchical goal-based formalism and algorithm for single-agent planning","authors":"Vikas Shivashankar, Ugur Kuter, Dana Nau, Ron Alford","year":"2012","venue":"AA-MAS","doi":null,"url":null,"internal_url":null},{"position":56,"raw":"[Shivashankar et al., 2013] Vikas Shivashankar, Ron Alford, Ugur Kuter, and Dana Nau. The GoDeL planning sys- tem: A more perfect union of domain-independent and hierarchical planning. In IJCAI, pages 2380-2386. AAAI Press, 2013.","title":"The GoDeL planning system: A more perfect union of domain-independent and hierarchical planning","authors":"Vikas Shivashankar, Ron Alford, Ugur Kuter, Dana Nau","year":"2013","venue":"IJCAI","doi":null,"url":null,"internal_url":"/proceedings/2013/350"},{"position":57,"raw":"[Shivashankar et al., 2016] Vikas Shivashankar, Ron Alford, Mark Roberts, and David W. Aha. Cost-optimal algo- rithms for planning with procedural control knowledge. In ECAI, pages 1702-1703. IOS Press, 2016.","title":"Cost-optimal algorithms for planning with procedural control knowledge","authors":"Vikas Shivashankar, Ron Alford, Mark Roberts, David W Aha","year":"2016","venue":"ECAI","doi":null,"url":null,"internal_url":null},{"position":58,"raw":"[Shivashankar et al., 2017] Vikas Shivashankar, Ron Alford, and David Aha. Incorporating domain-independent plan- ning heuristics in hierarchical planning. In AAAI, pages 3658-3664. AAAI Press, 2017.","title":"Incorporating domain-independent planning heuristics in hierarchical planning","authors":"Vikas Shivashankar, Ron Alford, David Aha","year":"2017","venue":"AAAI","doi":null,"url":null,"internal_url":null},{"position":59,"raw":"[Sirin et al., 2004] Evren Sirin, Bijan Parsia, Dan Wu, James Hendler, and Dana Nau. HTN planning for web service composition using SHOP2. Journal of Web Semantics, 1(4):377-396, 2004.","title":"HTN planning for web service composition using SHOP2","authors":"Evren Sirin, Bijan Parsia, Dan Wu, James Hendler, Dana Nau","year":"2004","venue":"Journal of Web Semantics","doi":null,"url":null,"internal_url":null},{"position":60,"raw":"[Smith et al., 2008] David E. Smith, Jeremy Frank, and William Cushing. The ANML language. In KEPS, 2008.","title":"The ANML language","authors":"David E Smith, Jeremy Frank, William Cushing","year":"2008","venue":"KEPS","doi":null,"url":null,"internal_url":null},{"position":61,"raw":"[Sohrabi et al., 2009] Shirin Sohrabi, Jorge A. Baier, and Sheila A. McIlraith. HTN planning with preferences. In IJCAI, pages 1790-1797. AAAI Press, 2009.","title":"HTN planning with preferences","authors":"Shirin Sohrabi, Jorge A Baier, Sheila A Mcilraith","year":"2009","venue":"IJCAI","doi":null,"url":null,"internal_url":"/proceedings/2009/298"},{"position":62,"raw":"[Stock et al., 2015] Sebastian Stock, Masoumeh Mansouri, Federico Pecora, and Joachim Hertzberg. Online task merging with a hierarchical hybrid task planner for mobile service robots. In IROS, pages 6459-6464. IEEE, 2015.","title":"Online task merging with a hierarchical hybrid task planner for mobile service robots","authors":"Sebastian Stock, Masoumeh Mansouri, Federico Pecora, Joachim Hertzberg","year":"2015","venue":"IROS","doi":null,"url":null,"internal_url":null},{"position":63,"raw":"[Winer and Young, 2016] David R. Winer and R. Michael Young. Discourse-driven narrative generation with bipar- tite planning. In INLG, pages 11-20. ACL, 2016.","title":"Discourse-driven narrative generation with bipartite planning","authors":"David R Winer, R Michael Young","year":"2016","venue":"INLG","doi":null,"url":null,"internal_url":null},{"position":64,"raw":"[Xiao et al., 2017] Zhanhao Xiao, Andreas Herzig, Laurent Perrussel, Hai Wan, and Xiaoheng Su. Hierarchical task network planning with task insertion and state constraints. In IJCAI, pages 4463-4469. IJCAI, 2017.","title":"Hierarchical task network planning with task insertion and state constraints","authors":"Xiao","year":"2017","venue":"IJCAI","doi":null,"url":null,"internal_url":"/proceedings/2017/623"},{"position":65,"raw":"[Young et al., 1994] R. Michael Young, Martha E. Pollack, and Johanna D. Moore. Decomposition and causality in partial-order planning. In AIPS, pages 188-193. AAAI Press, 1994.","title":"Decomposition and causality in partial-order planning","authors":"R Michael Young, Martha E Pollack, Johanna D Moore","year":"1994","venue":"AIPS","doi":null,"url":null,"internal_url":null}],"license_note":"Copyright International Joint Conferences on Artificial Intelligence."}