{"id":"https://openalex.org/W2071578511","doi":"https://doi.org/10.1016/0306-4379(88)90040-3","title":"Extending relational algebra to manipulate temporal data","display_name":"Extending relational algebra to manipulate temporal data","publication_year":1988,"publication_date":"1988-01-01","ids":{"openalex":"https://openalex.org/W2071578511","doi":"https://doi.org/10.1016/0306-4379(88)90040-3","mag":"2071578511"},"language":"en","primary_location":{"id":"doi:10.1016/0306-4379(88)90040-3","is_oa":false,"landing_page_url":"https://doi.org/10.1016/0306-4379(88)90040-3","pdf_url":null,"source":{"id":"https://openalex.org/S193006928","display_name":"Information Systems","issn_l":"0306-4379","issn":["0306-4379","1873-6076"],"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":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Information Systems","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/A5108493610","display_name":"Nikos A. Lorentzos","orcid":null},"institutions":[{"id":"https://openalex.org/I124357947","display_name":"University of London","ror":"https://ror.org/04cw6st05","country_code":"GB","type":"education","lineage":["https://openalex.org/I124357947"]},{"id":"https://openalex.org/I98259816","display_name":"Birkbeck, University of London","ror":"https://ror.org/02mb95055","country_code":"GB","type":"education","lineage":["https://openalex.org/I124357947","https://openalex.org/I98259816"]}],"countries":["GB"],"is_corresponding":false,"raw_author_name":"Nikos A. Lorentzos","raw_affiliation_strings":["Department of Computer Science, Birkbeck College, London University, Malet Street, London WC1E 7HX, U.K","[London University, London, UK]"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Department of Computer Science, Birkbeck College, London University, Malet Street, London WC1E 7HX, U.K","institution_ids":["https://openalex.org/I98259816"]},{"raw_affiliation_string":"[London University, London, UK]","institution_ids":["https://openalex.org/I124357947"]}]},{"author_position":"last","author":{"id":"https://openalex.org/A5039472328","display_name":"Roger G. Johnson","orcid":null},"institutions":[{"id":"https://openalex.org/I124357947","display_name":"University of London","ror":"https://ror.org/04cw6st05","country_code":"GB","type":"education","lineage":["https://openalex.org/I124357947"]},{"id":"https://openalex.org/I98259816","display_name":"Birkbeck, University of London","ror":"https://ror.org/02mb95055","country_code":"GB","type":"education","lineage":["https://openalex.org/I124357947","https://openalex.org/I98259816"]}],"countries":["GB"],"is_corresponding":false,"raw_author_name":"Roger G. Johnson","raw_affiliation_strings":["Department of Computer Science, Birkbeck College, London University, Malet Street, London WC1E 7HX, U.K","[London University, London, UK]"],"raw_orcid":null,"affiliations":[{"raw_affiliation_string":"Department of Computer Science, Birkbeck College, London University, Malet Street, London WC1E 7HX, U.K","institution_ids":["https://openalex.org/I98259816"]},{"raw_affiliation_string":"[London University, London, UK]","institution_ids":["https://openalex.org/I124357947"]}]}],"institutions":[],"countries_distinct_count":1,"institutions_distinct_count":2,"corresponding_author_ids":[],"corresponding_institution_ids":[],"apc_list":{"value":2970,"currency":"USD","value_usd":2970},"apc_paid":null,"fwci":3.5151,"has_fulltext":false,"cited_by_count":94,"citation_normalized_percentile":{"value":0.92607562,"is_in_top_1_percent":false,"is_in_top_10_percent":true},"cited_by_percentile_year":{"min":90,"max":98},"biblio":{"volume":"13","issue":"3","first_page":"289","last_page":"296"},"is_retracted":false,"is_paratext":false,"is_xpac":false,"primary_topic":{"id":"https://openalex.org/T10317","display_name":"Advanced Database Systems and Queries","score":0.9994000196456909,"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/T10317","display_name":"Advanced Database Systems and Queries","score":0.9994000196456909,"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/T11106","display_name":"Data Management and Algorithms","score":0.9933000206947327,"subfield":{"id":"https://openalex.org/subfields/1711","display_name":"Signal Processing"},"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/T10215","display_name":"Semantic Web and Ontologies","score":0.9890000224113464,"subfield":{"id":"https://openalex.org/subfields/1702","display_name":"Artificial Intelligence"},"field":{"id":"https://openalex.org/fields/17","display_name":"Computer Science"},"domain":{"id":"https://openalex.org/domains/3","display_name":"Physical Sciences"}}],"keywords":[{"id":"https://openalex.org/keywords/relational-algebra","display_name":"Relational algebra","score":0.8604455590248108},{"id":"https://openalex.org/keywords/computer-science","display_name":"Computer science","score":0.7931890487670898},{"id":"https://openalex.org/keywords/extension","display_name":"Extension (predicate logic)","score":0.6456214785575867},{"id":"https://openalex.org/keywords/relational-database","display_name":"Relational database","score":0.6242257356643677},{"id":"https://openalex.org/keywords/simple","display_name":"Simple (philosophy)","score":0.5489941835403442},{"id":"https://openalex.org/keywords/strengths-and-weaknesses","display_name":"Strengths and weaknesses","score":0.5131264328956604},{"id":"https://openalex.org/keywords/relational-model","display_name":"Relational model","score":0.4973590672016144},{"id":"https://openalex.org/keywords/relational-calculus","display_name":"Relational calculus","score":0.47125008702278137},{"id":"https://openalex.org/keywords/algebra-over-a-field","display_name":"Algebra over a field","score":0.41588613390922546},{"id":"https://openalex.org/keywords/theoretical-computer-science","display_name":"Theoretical computer science","score":0.37362921237945557},{"id":"https://openalex.org/keywords/programming-language","display_name":"Programming language","score":0.31843942403793335},{"id":"https://openalex.org/keywords/information-retrieval","display_name":"Information retrieval","score":0.27104341983795166},{"id":"https://openalex.org/keywords/mathematics","display_name":"Mathematics","score":0.10758039355278015}],"concepts":[{"id":"https://openalex.org/C95916125","wikidata":"https://www.wikidata.org/wiki/Q840540","display_name":"Relational algebra","level":3,"score":0.8604455590248108},{"id":"https://openalex.org/C41008148","wikidata":"https://www.wikidata.org/wiki/Q21198","display_name":"Computer science","level":0,"score":0.7931890487670898},{"id":"https://openalex.org/C2778029271","wikidata":"https://www.wikidata.org/wiki/Q5421931","display_name":"Extension (predicate logic)","level":2,"score":0.6456214785575867},{"id":"https://openalex.org/C5655090","wikidata":"https://www.wikidata.org/wiki/Q192588","display_name":"Relational database","level":2,"score":0.6242257356643677},{"id":"https://openalex.org/C2780586882","wikidata":"https://www.wikidata.org/wiki/Q7520643","display_name":"Simple (philosophy)","level":2,"score":0.5489941835403442},{"id":"https://openalex.org/C63882131","wikidata":"https://www.wikidata.org/wiki/Q17122954","display_name":"Strengths and weaknesses","level":2,"score":0.5131264328956604},{"id":"https://openalex.org/C40207289","wikidata":"https://www.wikidata.org/wiki/Q755662","display_name":"Relational model","level":3,"score":0.4973590672016144},{"id":"https://openalex.org/C99436015","wikidata":"https://www.wikidata.org/wiki/Q1722436","display_name":"Relational calculus","level":4,"score":0.47125008702278137},{"id":"https://openalex.org/C136119220","wikidata":"https://www.wikidata.org/wiki/Q1000660","display_name":"Algebra over a field","level":2,"score":0.41588613390922546},{"id":"https://openalex.org/C80444323","wikidata":"https://www.wikidata.org/wiki/Q2878974","display_name":"Theoretical computer science","level":1,"score":0.37362921237945557},{"id":"https://openalex.org/C199360897","wikidata":"https://www.wikidata.org/wiki/Q9143","display_name":"Programming language","level":1,"score":0.31843942403793335},{"id":"https://openalex.org/C23123220","wikidata":"https://www.wikidata.org/wiki/Q816826","display_name":"Information retrieval","level":1,"score":0.27104341983795166},{"id":"https://openalex.org/C33923547","wikidata":"https://www.wikidata.org/wiki/Q395","display_name":"Mathematics","level":0,"score":0.10758039355278015},{"id":"https://openalex.org/C111472728","wikidata":"https://www.wikidata.org/wiki/Q9471","display_name":"Epistemology","level":1,"score":0.0},{"id":"https://openalex.org/C138885662","wikidata":"https://www.wikidata.org/wiki/Q5891","display_name":"Philosophy","level":0,"score":0.0},{"id":"https://openalex.org/C202444582","wikidata":"https://www.wikidata.org/wiki/Q837863","display_name":"Pure mathematics","level":1,"score":0.0}],"mesh":[],"locations_count":2,"locations":[{"id":"doi:10.1016/0306-4379(88)90040-3","is_oa":false,"landing_page_url":"https://doi.org/10.1016/0306-4379(88)90040-3","pdf_url":null,"source":{"id":"https://openalex.org/S193006928","display_name":"Information Systems","issn_l":"0306-4379","issn":["0306-4379","1873-6076"],"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":null,"license_id":null,"version":"publishedVersion","is_accepted":true,"is_published":true,"raw_source_name":"Information Systems","raw_type":"journal-article"},{"id":"pmh:oai:eprints.bbk.ac.uk.oai2:44016","is_oa":false,"landing_page_url":"https://eprints.bbk.ac.uk/id/eprint/44016/","pdf_url":null,"source":{"id":"https://openalex.org/S4306400466","display_name":"BIROn (Birkbeck, University of London)","issn_l":null,"issn":null,"is_oa":false,"is_in_doaj":false,"is_core":false,"host_organization":"https://openalex.org/I98259816","host_organization_name":"Birkbeck, University of London","host_organization_lineage":["https://openalex.org/I98259816"],"host_organization_lineage_names":[],"type":"repository"},"license":null,"license_id":null,"version":"submittedVersion","is_accepted":false,"is_published":false,"raw_source_name":"","raw_type":"Article"}],"best_oa_location":null,"sustainable_development_goals":[],"awards":[],"funders":[],"has_content":{"grobid_xml":false,"pdf":false},"content_urls":null,"referenced_works_count":30,"referenced_works":["https://openalex.org/W62675080","https://openalex.org/W69288136","https://openalex.org/W164962280","https://openalex.org/W1517332488","https://openalex.org/W1562294322","https://openalex.org/W1573002516","https://openalex.org/W1576744908","https://openalex.org/W1977662461","https://openalex.org/W2000895568","https://openalex.org/W2002467602","https://openalex.org/W2005471433","https://openalex.org/W2110788116","https://openalex.org/W2112773424","https://openalex.org/W2122789628","https://openalex.org/W2169447117","https://openalex.org/W2489748212","https://openalex.org/W2984206580","https://openalex.org/W3121343637","https://openalex.org/W4239571647","https://openalex.org/W4285719527","https://openalex.org/W6602589861","https://openalex.org/W6602808799","https://openalex.org/W6604514625","https://openalex.org/W6606651219","https://openalex.org/W6630947089","https://openalex.org/W6633499690","https://openalex.org/W6634161761","https://openalex.org/W6650994307","https://openalex.org/W6676664557","https://openalex.org/W6684578141"],"related_works":["https://openalex.org/W2085988990","https://openalex.org/W2056340443","https://openalex.org/W2005835473","https://openalex.org/W2378275298","https://openalex.org/W60748262","https://openalex.org/W3174970460","https://openalex.org/W2056147406","https://openalex.org/W2376710457","https://openalex.org/W206482712","https://openalex.org/W2156787493"],"abstract_inverted_index":null,"counts_by_year":[{"year":2022,"cited_by_count":2},{"year":2021,"cited_by_count":2},{"year":2018,"cited_by_count":5},{"year":2017,"cited_by_count":1},{"year":2016,"cited_by_count":4},{"year":2014,"cited_by_count":2},{"year":2013,"cited_by_count":1}],"updated_date":"2026-06-11T09:08:48.828518","created_date":"2025-10-10T00:00:00"}
