{"publication_identifier":{"issn":["0097-5397"],"eissn":["1095-7111"]},"extern":"1","type":"journal_article","date_updated":"2023-02-17T14:41:36Z","volume":29,"abstract":[{"lang":"eng","text":"We consider exploration problems where a robot has to construct a complete map of an unknown environment. We assume that the environment is modeled by a directed, strongly connected graph. The robot's task is to visit all nodes and edges of the graph using the minimum number R of edge traversals. Deng and Papadimitriou [Proceedings of the 31st Symposium on the Foundations of Computer Science, 1990, pp. 356-361] showed an upper bound for R ofd O(d)m and Koutsoupias (reported by Deng and Papadimitriou) gave a lower bound of Ω≠(d2m), where m is the number of edges in the graph and d is the minimum number of edges that have to be added to make the graph Eulerian.  We give the 1rst subexponential algorithm for this exploration problem, which achieves an upper bound of dO(logd)m.  We also show a matching lower bound of d≠(logd)m for our algorithm. Additionally, we give lower bounds of 2≠(d)m, respectively, d≠(logd)m for various other natural exploration algorithms."}],"publication":"SIAM Journal on Computing","publication_status":"published","_id":"11694","conference":{"name":"STOC97: 29th Annual Symposium on Theory of Computing","location":"El Paso, TX, United States","start_date":"1997-05-04","end_date":"1997-05-06"},"doi":"10.1137/s009753979732428x","author":[{"first_name":"Susanne","full_name":"Albers, Susanne","last_name":"Albers"},{"orcid":"0000-0002-5008-6530","full_name":"Henzinger, Monika H","first_name":"Monika H","id":"540c9bbd-f2de-11ec-812d-d04a5be85630","last_name":"Henzinger"}],"month":"07","date_created":"2022-07-29T09:04:36Z","citation":{"apa":"Albers, S., &#38; Henzinger, M. H. (2000). Exploring unknown environments. <i>SIAM Journal on Computing</i>. El Paso, TX, United States: Society for Industrial and Applied Mathematics. <a href=\"https://doi.org/10.1137/s009753979732428x\">https://doi.org/10.1137/s009753979732428x</a>","ista":"Albers S, Henzinger MH. 2000. Exploring unknown environments. SIAM Journal on Computing. 29(4), 1164–1188.","chicago":"Albers, Susanne, and Monika H Henzinger. “Exploring Unknown Environments.” <i>SIAM Journal on Computing</i>. Society for Industrial and Applied Mathematics, 2000. <a href=\"https://doi.org/10.1137/s009753979732428x\">https://doi.org/10.1137/s009753979732428x</a>.","ieee":"S. Albers and M. H. Henzinger, “Exploring unknown environments,” <i>SIAM Journal on Computing</i>, vol. 29, no. 4. Society for Industrial and Applied Mathematics, pp. 1164–1188, 2000.","ama":"Albers S, Henzinger MH. Exploring unknown environments. <i>SIAM Journal on Computing</i>. 2000;29(4):1164-1188. doi:<a href=\"https://doi.org/10.1137/s009753979732428x\">10.1137/s009753979732428x</a>","mla":"Albers, Susanne, and Monika H. Henzinger. “Exploring Unknown Environments.” <i>SIAM Journal on Computing</i>, vol. 29, no. 4, Society for Industrial and Applied Mathematics, 2000, pp. 1164–88, doi:<a href=\"https://doi.org/10.1137/s009753979732428x\">10.1137/s009753979732428x</a>.","short":"S. Albers, M.H. Henzinger, SIAM Journal on Computing 29 (2000) 1164–1188."},"acknowledgement":"We thank Prabhakar Raghavan for bringing to our attention the literature on the s-t connectivity  problem. We also thank  an anonymous referee for many helpful comments which improved the presentation of the paper.","article_processing_charge":"No","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","status":"public","page":"1164-1188","language":[{"iso":"eng"}],"intvolume":"        29","oa_version":"None","issue":"4","quality_controlled":"1","scopus_import":"1","title":"Exploring unknown environments","keyword":["directed graph","exploration algorithm"],"date_published":"2000-07-01T00:00:00Z","day":"01","article_type":"original","year":"2000","publisher":"Society for Industrial and Applied Mathematics"}