{"id":"https://openalex.org/W7126182442","doi":"https://doi.org/10.1016/j.tcs.2026.115776","title":"Gathering semi-synchronously scheduled two-state robots","display_name":"Gathering semi-synchronously scheduled two-state robots","publication_year":2026,"publication_date":"2026-01-30","ids":{"openalex":"https://openalex.org/W7126182442","doi":"https://doi.org/10.1016/j.tcs.2026.115776"},"language":"en","primary_location":{"id":"doi:10.1016/j.tcs.2026.115776","is_oa":true,"landing_page_url":"https://doi.org/10.1016/j.tcs.2026.115776","pdf_url":null,"source":{"id":"https://openalex.org/S90727058","display_name":"Theoretical Computer Science","issn_l":"0304-3975","issn":["0304-3975","1879-2294"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310320990","host_organization_name":"Elsevier BV","host_organization_lineage":["https://openalex.org/P4310320990"],"host_organization_lineage_names":["Elsevier BV"],"type":"journal"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Theoretical Computer Science","raw_type":"journal-article"},"type":"article","indexed_in":["crossref"],"open_access":{"is_oa":true,"oa_status":"hybrid","oa_url":"https://doi.org/10.1016/j.tcs.2026.115776","any_repository_has_fulltext":true},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5107179523","display_name":"Kohei Otaka","orcid":null},"institutions":[{"id":"https://openalex.org/I204291657","display_name":"Hosei University","ror":"https://ror.org/00bx6dj65","country_code":"JP","type":"education","lineage":["https://openalex.org/I204291657"]}],"countries":["JP"],"is_corresponding":false,"raw_author_name":"Kohei Otaka","raw_affiliation_strings":["Graduate School of Science and Engineering, Hosei University, Tokyo, 184-8485, Japan"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Graduate School of Science and Engineering, Hosei University, Tokyo, 184-8485, Japan","institution_ids":["https://openalex.org/I204291657"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5097223189","display_name":"Fabian Frei","orcid":null},"institutions":[{"id":"https://openalex.org/I4210128801","display_name":"Helmholtz Center for Information Security","ror":"https://ror.org/02njgxr09","country_code":"DE","type":"facility","lineage":["https://openalex.org/I1305996414","https://openalex.org/I4210128801"]}],"countries":["DE"],"is_corresponding":false,"raw_author_name":"Fabian Frei","raw_affiliation_strings":["ETH Zurich, Department of Computer Science, Z\u00fcrich, Switzerland, CISPA Helmholtz Center for Information Security, Saarbr\u00fccken, Germany, Massachusetts Institute of Technology, CSAIL, Cambridge, MA, United States of America"],"raw_orcid":"https://orcid.org/0000-0002-1368-3205","affiliations":[{"raw_affiliation_string":"ETH Zurich, Department of Computer Science, Z\u00fcrich, Switzerland, CISPA Helmholtz Center for Information Security, Saarbr\u00fccken, Germany, Massachusetts Institute of Technology, CSAIL, Cambridge, MA, United States of America","institution_ids":["https://openalex.org/I4210128801"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5027866181","display_name":"Koichi Wada","orcid":"https://orcid.org/0000-0001-9271-5641"},"institutions":[{"id":"https://openalex.org/I204291657","display_name":"Hosei University","ror":"https://ror.org/00bx6dj65","country_code":"JP","type":"education","lineage":["https://openalex.org/I204291657"]}],"countries":["JP"],"is_corresponding":true,"raw_author_name":"Koichi Wada","raw_affiliation_strings":["Faculty of Science and Engineering, Hosei University, Tokyo, 184-8485, Japan"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Faculty of Science and Engineering, Hosei University, Tokyo, 184-8485, Japan","institution_ids":["https://openalex.org/I204291657"]}]}],"institutions":[],"countries_distinct_count":2,"institutions_distinct_count":3,"corresponding_author_ids":["https://openalex.org/A5027866181"],"corresponding_institution_ids":["https://openalex.org/I204291657"],"apc_list":{"value":2690,"currency":"USD","value_usd":2690},"apc_paid":{"value":2690,"currency":"USD","value_usd":2690},"fwci":0.0,"has_fulltext":false,"cited_by_count":0,"citation_normalized_percentile":{"value":0.16738137,"is_in_top_1_percent":false,"is_in_top_10_percent":false},"cited_by_percentile_year":null,"biblio":{"volume":"1068","issue":null,"first_page":"115776","last_page":"115776"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T12288","display_name":"Optimization and Search Problems","score":0.9674000144004822,"subfield":{"id":"https://openalex.org/subfields/1705","display_name":"Computer Networks and Communications"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T12288","display_name":"Optimization and Search Problems","score":0.9674000144004822,"subfield":{"id":"https://openalex.org/subfields/1705","display_name":"Computer Networks and Communications"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T10249","display_name":"Distributed Control Multi-Agent Systems","score":0.013299999758601189,"subfield":{"id":"https://openalex.org/subfields/1705","display_name":"Computer Networks and Communications"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T12784","display_name":"Modular Robots and Swarm Intelligence","score":0.004399999976158142,"subfield":{"id":"https://openalex.org/subfields/2210","display_name":"Mechanical Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/robot","display_name":"Robot","score":0.8772000074386597},{"id":"https://openalex.org/keywords/mobile-robot","display_name":"Mobile robot","score":0.6115000247955322},{"id":"https://openalex.org/keywords/focus","display_name":"Focus (optics)","score":0.5835999846458435},{"id":"https://openalex.org/keywords/set","display_name":"Set (abstract data type)","score":0.5727999806404114},{"id":"https://openalex.org/keywords/constructive","display_name":"Constructive","score":0.5030999779701233},{"id":"https://openalex.org/keywords/constant","display_name":"Constant (computer programming)","score":0.45579999685287476}],"concepts":[{"id":"https://openalex.org/C90509273","wikidata":"https://www.wikidata.org/wiki/Q11012","display_name":"Robot","level":2,"score":0.8772000074386597},{"id":"https://openalex.org/C19966478","wikidata":"https://www.wikidata.org/wiki/Q4810574","display_name":"Mobile robot","level":3,"score":0.6115000247955322},{"id":"https://openalex.org/C192209626","wikidata":"https://www.wikidata.org/wiki/Q190909","display_name":"Focus (optics)","level":2,"score":0.5835999846458435},{"id":"https://openalex.org/C177264268","wikidata":"https://www.wikidata.org/wiki/Q1514741","display_name":"Set (abstract data type)","level":2,"score":0.5727999806404114},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.5618000030517578},{"id":"https://openalex.org/C2778701210","wikidata":"https://www.wikidata.org/wiki/Q28130034","display_name":"Constructive","level":3,"score":0.5030999779701233},{"id":"https://openalex.org/C2777027219","wikidata":"https://www.wikidata.org/wiki/Q1284190","display_name":"Constant (computer programming)","level":2,"score":0.45579999685287476},{"id":"https://openalex.org/C154945302","wikidata":"https://www.wikidata.org/wiki/Q11660","display_name":"Artificial intelligence","level":1,"score":0.43639999628067017},{"id":"https://openalex.org/C11413529","wikidata":"https://www.wikidata.org/wiki/Q8366","display_name":"Algorithm","level":1,"score":0.32989999651908875},{"id":"https://openalex.org/C31972630","wikidata":"https://www.wikidata.org/wiki/Q844240","display_name":"Computer vision","level":1,"score":0.2906000018119812},{"id":"https://openalex.org/C34413123","wikidata":"https://www.wikidata.org/wiki/Q170978","display_name":"Robotics","level":3,"score":0.2849999964237213},{"id":"https://openalex.org/C33923547","wikidata":"https://www.wikidata.org/wiki/Q395","display_name":"Mathematics","level":0,"score":0.2840000092983246},{"id":"https://openalex.org/C44832474","wikidata":"https://www.wikidata.org/wiki/Q4770870","display_name":"Ant robotics","level":5,"score":0.26969999074935913},{"id":"https://openalex.org/C65401140","wikidata":"https://www.wikidata.org/wiki/Q7353385","display_name":"Robot control","level":4,"score":0.26249998807907104},{"id":"https://openalex.org/C49603950","wikidata":"https://www.wikidata.org/wiki/Q17165512","display_name":"Self-reconfiguring modular robot","level":5,"score":0.2554999887943268},{"id":"https://openalex.org/C80444323","wikidata":"https://www.wikidata.org/wiki/Q2878974","display_name":"Theoretical computer science","level":1,"score":0.2502000033855438}],"mesh":[],"locations_count":2,"locations":[{"id":"doi:10.1016/j.tcs.2026.115776","is_oa":true,"landing_page_url":"https://doi.org/10.1016/j.tcs.2026.115776","pdf_url":null,"source":{"id":"https://openalex.org/S90727058","display_name":"Theoretical Computer Science","issn_l":"0304-3975","issn":["0304-3975","1879-2294"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310320990","host_organization_name":"Elsevier BV","host_organization_lineage":["https://openalex.org/P4310320990"],"host_organization_lineage_names":["Elsevier BV"],"type":"journal"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Theoretical Computer Science","raw_type":"journal-article"},{"id":"pmh:doi:10.3929/ethz-c-000795793","is_oa":true,"landing_page_url":"http://hdl.handle.net/20.500.11850/795793","pdf_url":null,"source":{"id":"https://openalex.org/S4406922384","display_name":"Open MIND","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":null,"host_organization_name":null,"host_organization_lineage":[],"host_organization_lineage_names":[],"type":"repository"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":null,"raw_type":"Journal Article"}],"best_oa_location":{"id":"doi:10.1016/j.tcs.2026.115776","is_oa":true,"landing_page_url":"https://doi.org/10.1016/j.tcs.2026.115776","pdf_url":null,"source":{"id":"https://openalex.org/S90727058","display_name":"Theoretical Computer Science","issn_l":"0304-3975","issn":["0304-3975","1879-2294"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310320990","host_organization_name":"Elsevier BV","host_organization_lineage":["https://openalex.org/P4310320990"],"host_organization_lineage_names":["Elsevier BV"],"type":"journal"},"license":"cc-by","license_id":"https://openalex.org/licenses/cc-by","version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Theoretical Computer Science","raw_type":"journal-article"},"sustainable_development_goals":[],"awards":[{"id":"https://openalex.org/G2892628498","display_name":null,"funder_award_id":"20K11685","funder_id":"https://openalex.org/F4320334764","funder_display_name":"Japan Society for the Promotion of Science"},{"id":"https://openalex.org/G4252465195","display_name":null,"funder_award_id":"21K11748","funder_id":"https://openalex.org/F4320334764","funder_display_name":"Japan Society for the Promotion of Science"},{"id":"https://openalex.org/G5065357814","display_name":null,"funder_award_id":"25K03079","funder_id":"https://openalex.org/F4320334764","funder_display_name":"Japan Society for the Promotion of Science"},{"id":"https://openalex.org/G5545636667","display_name":null,"funder_award_id":"25K03078","funder_id":"https://openalex.org/F4320334764","funder_display_name":"Japan Society for the Promotion of Science"},{"id":"https://openalex.org/G5994573828","display_name":null,"funder_award_id":"218001","funder_id":"https://openalex.org/F4320320924","funder_display_name":"Schweizerischer Nationalfonds zur F\u00f6rderung der Wissenschaftlichen Forschung"}],"funders":[{"id":"https://openalex.org/F4320320924","display_name":"Schweizerischer Nationalfonds zur F\u00f6rderung der Wissenschaftlichen Forschung","ror":"https://ror.org/00yjd3n13"},{"id":"https://openalex.org/F4320334764","display_name":"Japan Society for the Promotion of Science","ror":"https://ror.org/00hhkn466"}],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":18,"referenced_works":["https://openalex.org/W1802748673","https://openalex.org/W1975531816","https://openalex.org/W1988782771","https://openalex.org/W2010017329","https://openalex.org/W2019654546","https://openalex.org/W2041571902","https://openalex.org/W2049232787","https://openalex.org/W2087073465","https://openalex.org/W2097569568","https://openalex.org/W2288393983","https://openalex.org/W2581043681","https://openalex.org/W2965788437","https://openalex.org/W3014020944","https://openalex.org/W3182674124","https://openalex.org/W4386170081","https://openalex.org/W4386566147","https://openalex.org/W4386977127","https://openalex.org/W4400409512"],"related_works":[],"abstract_inverted_index":{"\u2022":[0,18,44,86],"We":[1,19,45,87,111,236,263],"study":[2,112],"the":[3,113,140,153,184,188,193,199,213],"Gathering":[4,65,108,115,136,160,249,267],"problem":[5,114],"for":[6,116,269],"n":[7,117],"mobile":[8,119],"robots":[9,28,38,102,120,147,189,217,229,246,273],"endowed":[10],"with":[11,59,68,103,124,230,256,274,277],"two-color":[12],"lights":[13,194,232],"in":[14,72,109,121,139,233,250],"semi-synchronous":[15,122,156],"(Ssynch)":[16],"environments.":[17],"focus":[20],"on":[21,95,225,261],"two":[22],"models:":[23],"F":[24,35,74,78,99,185,200,226,240,244,270],"ST":[25,75,100,201,227,241,271],"A":[26,76,101,202,228,242,272],"(where":[27,37],"see":[29,39,192,219],"only":[30,40,69,191,207],"their":[31],"own":[32,210],"light)":[33],"and":[34,62,77,243,259],"COM":[36,79,186,245],"each":[41,165,204],"others\u2019":[42],"lights).":[43],"prove":[46],"existing":[47],"upper":[48],"bounds":[49],"to":[50,177],"be":[51,175],"optimal.":[52],"In":[53,183,198,212],"particular,":[54],"we":[55],"show":[56,237,265],"that,":[57,93],"even":[58,151,255],"rigid":[60,257],"movement":[61,258],"consistent":[63],"chirality,":[64],"is":[66,132,137,155],"impossible":[67,138],"2":[70,104],"colors":[71,105],"both":[73],"under":[80],"Ssynchunless":[81],"additional":[82,253,279],"assumptions":[83],"are":[84],"introduced.":[85],"provide":[88],"a":[89,125,168,178,266],"constructive":[90],"algorithm":[91,268],"demonstrating":[92],"relying":[94],"minimal":[96,278],"extra":[97],"assumptions,":[98,254],"can":[106,174,190,206,218],"solve":[107,248],"Ssynch.":[110],"autonomous":[118],"settings":[123],"persistent":[126],"memory":[127],"called":[128],"light":[129,169],".":[130],"It":[131],"well":[133],"known":[134],"that":[135,173,238],"basic":[141],"model":[142],"(":[143],"OBLOT":[144],")":[145],"where":[146],"have":[148],"no":[149],"lights,":[150],"if":[152,164],"system":[154],"(called":[157],"Ssynch":[158,251,276],").":[159],"becomes":[161],"possible,":[162],"however,":[163],"robot":[166,205],"has":[167],"of":[170,181,195],"some":[171],"type":[172],"set":[176],"constant":[179],"number":[180],"colors.":[182],"model,":[187,203,215],"other":[196],"robots.":[197],"observe":[208],"its":[209],"light.":[211],"LUMI":[214],"all":[216,220],"lights.":[221],"This":[222],"paper":[223],"focuses":[224],"2-colored":[231],"synchronous":[234],"settings.":[235],"2-color":[239,275],"cannot":[247],"without":[252],"agreement":[260],"chirality.":[262],"also":[264],"assumptions.":[280]},"counts_by_year":[],"updated_date":"2026-02-06T02:01:19.302388","created_date":"2026-02-01T00:00:00"}
