{"id":"https://openalex.org/W2047538092","doi":"https://doi.org/10.1137/070700322","title":"Unknown Input and State Estimation for Unobservable Systems","display_name":"Unknown Input and State Estimation for Unobservable Systems","publication_year":2009,"publication_date":"2009-01-01","ids":{"openalex":"https://openalex.org/W2047538092","doi":"https://doi.org/10.1137/070700322","mag":"2047538092"},"language":"en","primary_location":{"id":"doi:10.1137/070700322","is_oa":false,"landing_page_url":"https://doi.org/10.1137/070700322","pdf_url":null,"source":{"id":"https://openalex.org/S897311980","display_name":"SIAM Journal on Control and Optimization","issn_l":"0363-0129","issn":["0363-0129","1095-7138"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310320508","host_organization_name":"Society for Industrial and Applied Mathematics","host_organization_lineage":["https://openalex.org/P4310320508"],"host_organization_lineage_names":["Society for Industrial and Applied Mathematics"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"SIAM Journal on Control and Optimization","raw_type":"journal-article"},"type":"article","indexed_in":["crossref"],"open_access":{"is_oa":false,"oa_status":"closed","oa_url":null,"any_repository_has_fulltext":false},"authorships":[{"author_position":"first","author":{"id":"https://openalex.org/A5091026086","display_name":"Francisco Javier Bejarano","orcid":"https://orcid.org/0000-0002-9141-4895"},"institutions":[{"id":"https://openalex.org/I8961855","display_name":"Universidad Nacional Aut\u00f3noma de M\u00e9xico","ror":"https://ror.org/01tmp8f25","country_code":"MX","type":"education","lineage":["https://openalex.org/I8961855"]}],"countries":["MX"],"is_corresponding":true,"raw_author_name":"Francisco J. Bejarano","raw_affiliation_strings":["javbejarano@yahoo.com.mx and lfridman@servidor.unam.mx#TAB#"],"affiliations":[{"raw_affiliation_string":"javbejarano@yahoo.com.mx and lfridman@servidor.unam.mx#TAB#","institution_ids":["https://openalex.org/I8961855"]}]},{"author_position":"middle","author":{"id":"https://openalex.org/A5032593897","display_name":"Leonid Fridman","orcid":"https://orcid.org/0000-0003-0208-3615"},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"Leonid Fridman","raw_affiliation_strings":[],"affiliations":[]},{"author_position":"last","author":{"id":"https://openalex.org/A5015067771","display_name":"Alexander S. Poznyak","orcid":"https://orcid.org/0000-0002-5378-4545"},"institutions":[],"countries":[],"is_corresponding":false,"raw_author_name":"Alexander Poznyak","raw_affiliation_strings":["apoznyak@ctrl.cinvestav.mx#TAB#"],"affiliations":[{"raw_affiliation_string":"apoznyak@ctrl.cinvestav.mx#TAB#","institution_ids":[]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":3,"corresponding_author_ids":["https://openalex.org/A5091026086"],"corresponding_institution_ids":["https://openalex.org/I8961855"],"apc_list":null,"apc_paid":null,"fwci":18.37,"has_fulltext":false,"cited_by_count":83,"citation_normalized_percentile":{"value":0.99189711,"is_in_top_1_percent":true,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":90,"max":99},"biblio":{"volume":"48","issue":"2","first_page":"1155","last_page":"1178"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10040","display_name":"Adaptive Control of Nonlinear Systems","score":0.9994999766349792,"subfield":{"id":"https://openalex.org/subfields/2207","display_name":"Control and Systems Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},"topics":[{"id":"https://openalex.org/T10040","display_name":"Adaptive Control of Nonlinear Systems","score":0.9994999766349792,"subfield":{"id":"https://openalex.org/subfields/2207","display_name":"Control and Systems Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T10046","display_name":"Stability and Control of Uncertain Systems","score":0.9991999864578247,"subfield":{"id":"https://openalex.org/subfields/2207","display_name":"Control and Systems Engineering"},"field":{"id":"https://openalex.org/fields/22","display_name":"Engineering"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}},{"id":"https://openalex.org/T10876","display_name":"Fault Detection and Control Systems","score":0.9991999864578247,"subfield":{"id":"https://openalex.org/subfields/2207","display_name":"Control and Systems 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/unobservable","display_name":"Unobservable","score":0.9719042778015137},{"id":"https://openalex.org/keywords/mathematics","display_name":"Mathematics","score":0.8279268145561218},{"id":"https://openalex.org/keywords/observable","display_name":"Observable","score":0.706100344657898},{"id":"https://openalex.org/keywords/observer","display_name":"Observer (physics)","score":0.5668228268623352},{"id":"https://openalex.org/keywords/invariant","display_name":"Invariant (physics)","score":0.5317004919052124},{"id":"https://openalex.org/keywords/state","display_name":"State (computer science)","score":0.5029038786888123},{"id":"https://openalex.org/keywords/state-vector","display_name":"State vector","score":0.4922274649143219},{"id":"https://openalex.org/keywords/complex-plane","display_name":"Complex plane","score":0.46977490186691284},{"id":"https://openalex.org/keywords/control-theory","display_name":"Control theory (sociology)","score":0.46947798132896423},{"id":"https://openalex.org/keywords/set","display_name":"Set (abstract data type)","score":0.4392159581184387},{"id":"https://openalex.org/keywords/state-space","display_name":"State space","score":0.42385342717170715},{"id":"https://openalex.org/keywords/applied-mathematics","display_name":"Applied mathematics","score":0.38821637630462646},{"id":"https://openalex.org/keywords/algorithm","display_name":"Algorithm","score":0.23999148607254028},{"id":"https://openalex.org/keywords/mathematical-analysis","display_name":"Mathematical analysis","score":0.2301613688468933},{"id":"https://openalex.org/keywords/control","display_name":"Control (management)","score":0.16362416744232178},{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.1261349320411682},{"id":"https://openalex.org/keywords/statistics","display_name":"Statistics","score":0.0898919403553009},{"id":"https://openalex.org/keywords/artificial-intelligence","display_name":"Artificial intelligence","score":0.07563731074333191},{"id":"https://openalex.org/keywords/econometrics","display_name":"Econometrics","score":0.07230019569396973}],"concepts":[{"id":"https://openalex.org/C2780695315","wikidata":"https://www.wikidata.org/wiki/Q3799040","display_name":"Unobservable","level":2,"score":0.9719042778015137},{"id":"https://openalex.org/C33923547","wikidata":"https://www.wikidata.org/wiki/Q395","display_name":"Mathematics","level":0,"score":0.8279268145561218},{"id":"https://openalex.org/C32848918","wikidata":"https://www.wikidata.org/wiki/Q845789","display_name":"Observable","level":2,"score":0.706100344657898},{"id":"https://openalex.org/C2780704645","wikidata":"https://www.wikidata.org/wiki/Q9251458","display_name":"Observer (physics)","level":2,"score":0.5668228268623352},{"id":"https://openalex.org/C190470478","wikidata":"https://www.wikidata.org/wiki/Q2370229","display_name":"Invariant (physics)","level":2,"score":0.5317004919052124},{"id":"https://openalex.org/C48103436","wikidata":"https://www.wikidata.org/wiki/Q599031","display_name":"State (computer science)","level":2,"score":0.5029038786888123},{"id":"https://openalex.org/C2777798563","wikidata":"https://www.wikidata.org/wiki/Q7603916","display_name":"State vector","level":2,"score":0.4922274649143219},{"id":"https://openalex.org/C179117685","wikidata":"https://www.wikidata.org/wiki/Q328998","display_name":"Complex plane","level":2,"score":0.46977490186691284},{"id":"https://openalex.org/C47446073","wikidata":"https://www.wikidata.org/wiki/Q5165890","display_name":"Control theory (sociology)","level":3,"score":0.46947798132896423},{"id":"https://openalex.org/C177264268","wikidata":"https://www.wikidata.org/wiki/Q1514741","display_name":"Set (abstract data type)","level":2,"score":0.4392159581184387},{"id":"https://openalex.org/C72434380","wikidata":"https://www.wikidata.org/wiki/Q230930","display_name":"State space","level":2,"score":0.42385342717170715},{"id":"https://openalex.org/C28826006","wikidata":"https://www.wikidata.org/wiki/Q33521","display_name":"Applied mathematics","level":1,"score":0.38821637630462646},{"id":"https://openalex.org/C11413529","wikidata":"https://www.wikidata.org/wiki/Q8366","display_name":"Algorithm","level":1,"score":0.23999148607254028},{"id":"https://openalex.org/C134306372","wikidata":"https://www.wikidata.org/wiki/Q7754","display_name":"Mathematical analysis","level":1,"score":0.2301613688468933},{"id":"https://openalex.org/C2775924081","wikidata":"https://www.wikidata.org/wiki/Q55608371","display_name":"Control (management)","level":2,"score":0.16362416744232178},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.1261349320411682},{"id":"https://openalex.org/C105795698","wikidata":"https://www.wikidata.org/wiki/Q12483","display_name":"Statistics","level":1,"score":0.0898919403553009},{"id":"https://openalex.org/C154945302","wikidata":"https://www.wikidata.org/wiki/Q11660","display_name":"Artificial intelligence","level":1,"score":0.07563731074333191},{"id":"https://openalex.org/C149782125","wikidata":"https://www.wikidata.org/wiki/Q160039","display_name":"Econometrics","level":1,"score":0.07230019569396973},{"id":"https://openalex.org/C121332964","wikidata":"https://www.wikidata.org/wiki/Q413","display_name":"Physics","level":0,"score":0.0},{"id":"https://openalex.org/C199360897","wikidata":"https://www.wikidata.org/wiki/Q9143","display_name":"Programming language","level":1,"score":0.0},{"id":"https://openalex.org/C74650414","wikidata":"https://www.wikidata.org/wiki/Q11397","display_name":"Classical mechanics","level":1,"score":0.0},{"id":"https://openalex.org/C62520636","wikidata":"https://www.wikidata.org/wiki/Q944","display_name":"Quantum mechanics","level":1,"score":0.0},{"id":"https://openalex.org/C37914503","wikidata":"https://www.wikidata.org/wiki/Q156495","display_name":"Mathematical physics","level":1,"score":0.0}],"mesh":[],"locations_count":1,"locations":[{"id":"doi:10.1137/070700322","is_oa":false,"landing_page_url":"https://doi.org/10.1137/070700322","pdf_url":null,"source":{"id":"https://openalex.org/S897311980","display_name":"SIAM Journal on Control and Optimization","issn_l":"0363-0129","issn":["0363-0129","1095-7138"],"is_oa":false,"is_in_doaj":false,"is_core":true,"host_organization":"https://openalex.org/P4310320508","host_organization_name":"Society for Industrial and Applied Mathematics","host_organization_lineage":["https://openalex.org/P4310320508"],"host_organization_lineage_names":["Society for Industrial and Applied Mathematics"],"type":"journal"},"license":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"SIAM Journal on Control and Optimization","raw_type":"journal-article"}],"best_oa_location":null,"sustainable_development_goals":[],"awards":[],"funders":[],"has_content":{"pdf":false,"grobid_xml":false},"content_urls":null,"referenced_works_count":23,"referenced_works":["https://openalex.org/W1507624518","https://openalex.org/W1979366106","https://openalex.org/W1999558720","https://openalex.org/W2001818647","https://openalex.org/W2010276843","https://openalex.org/W2018466653","https://openalex.org/W2018851823","https://openalex.org/W2030959268","https://openalex.org/W2032278511","https://openalex.org/W2050205901","https://openalex.org/W2059385844","https://openalex.org/W2064286311","https://openalex.org/W2108929677","https://openalex.org/W2117931050","https://openalex.org/W2128141484","https://openalex.org/W2143522667","https://openalex.org/W2149811200","https://openalex.org/W2157171845","https://openalex.org/W2186137641","https://openalex.org/W2226779849","https://openalex.org/W2503310670","https://openalex.org/W2560941241","https://openalex.org/W3002318169"],"related_works":["https://openalex.org/W2008534419","https://openalex.org/W1578306890","https://openalex.org/W4384915695","https://openalex.org/W2065742713","https://openalex.org/W83966473","https://openalex.org/W1976452401","https://openalex.org/W2066279242","https://openalex.org/W2488352885","https://openalex.org/W4238593844","https://openalex.org/W2030111109"],"abstract_inverted_index":{"The":[0],"concept":[1,10],"of":[2,11,32,41,88,99,106,111,135,144],"strong":[3,59],"detectability":[4,60],"and":[5,76],"its":[6],"relation":[7],"with":[8],"the":[9,22,42,67,74,81,86,89,97,104,107,112,118,131,136,142,145],"invariant":[12,90],"zeros":[13,91],"is":[14,27,48,54,61,71,84,127],"reviewed.":[15],"For":[16],"strongly":[17,23],"detectable":[18],"systems":[19],"(which":[20],"includes":[21],"observable":[24],"systems),":[25],"it":[26,47,126],"proposed":[28,146],"a":[29,33,55,62],"hierarchical":[30],"design":[31],"robust":[34],"observer":[35],"whose":[36],"trajectories":[37],"converge":[38],"to":[39,65,96,129],"those":[40],"original":[43],"state":[44,133],"vector.":[45],"Furthermore,":[46],"shown":[49,72],"that":[50,73,85,92,117],"neither":[51],"left":[52,108],"invertibility":[53],"sufficient":[56,77],"condition":[57,64,78],"nor":[58],"necessary":[63,75],"estimate":[66,130],"unknown":[68,82,119],"inputs.":[69],"It":[70],"for":[79],"estimating":[80],"inputs":[83,120],"set":[87,98],"do":[93],"not":[94],"belong":[95],"unobservable":[100],"modes":[101],"be":[102,122],"within":[103],"interior":[105],"half":[109],"plane":[110],"complex":[113],"space.":[114],"This":[115],"shows":[116],"could":[121],"estimated":[123],"even":[124],"if":[125],"impossible":[128],"entire":[132],"vector":[134],"system.":[137],"Two":[138],"numerical":[139],"examples":[140],"illustrate":[141],"effectiveness":[143],"estimation":[147],"schemes.":[148]},"counts_by_year":[{"year":2026,"cited_by_count":1},{"year":2025,"cited_by_count":5},{"year":2024,"cited_by_count":1},{"year":2023,"cited_by_count":5},{"year":2022,"cited_by_count":4},{"year":2021,"cited_by_count":5},{"year":2020,"cited_by_count":7},{"year":2019,"cited_by_count":4},{"year":2018,"cited_by_count":1},{"year":2017,"cited_by_count":7},{"year":2016,"cited_by_count":5},{"year":2015,"cited_by_count":5},{"year":2014,"cited_by_count":6},{"year":2013,"cited_by_count":3},{"year":2012,"cited_by_count":9}],"updated_date":"2025-11-06T03:46:38.306776","created_date":"2025-10-10T00:00:00"}
