[{"page":"191-221","quality_controlled":"1","article_type":"original","publisher":"Taylor & Francis","author":[{"first_name":"D.","last_name":"Dikranjan","full_name":"Dikranjan, D."},{"full_name":"Giordano Bruno, A.","first_name":"A.","last_name":"Giordano Bruno"},{"orcid":"0000-0001-8686-1888","full_name":"Zava, Nicolò","first_name":"Nicolò","last_name":"Zava","id":"c8b3499c-7a77-11eb-b046-aa368cbbf2ad"}],"issue":"S1","_id":"14557","scopus_import":"1","title":"Epimorphisms and closure operators of categories of semilattices","intvolume":"        46","publication_status":"published","article_processing_charge":"No","department":[{"_id":"HeEd"}],"date_created":"2023-11-19T23:00:55Z","acknowledgement":"The first and second named authors are members of GNSAGA – INdAM.\r\nThe third named author was supported by the FWF Grant, Project number I4245–N35","volume":46,"date_updated":"2023-11-20T09:24:48Z","citation":{"ama":"Dikranjan D, Giordano Bruno A, Zava N. Epimorphisms and closure operators of categories of semilattices. <i>Quaestiones Mathematicae</i>. 2023;46(S1):191-221. doi:<a href=\"https://doi.org/10.2989/16073606.2023.2247731\">10.2989/16073606.2023.2247731</a>","apa":"Dikranjan, D., Giordano Bruno, A., &#38; Zava, N. (2023). Epimorphisms and closure operators of categories of semilattices. <i>Quaestiones Mathematicae</i>. Taylor &#38; Francis. <a href=\"https://doi.org/10.2989/16073606.2023.2247731\">https://doi.org/10.2989/16073606.2023.2247731</a>","ieee":"D. Dikranjan, A. Giordano Bruno, and N. Zava, “Epimorphisms and closure operators of categories of semilattices,” <i>Quaestiones Mathematicae</i>, vol. 46, no. S1. Taylor &#38; Francis, pp. 191–221, 2023.","chicago":"Dikranjan, D., A. Giordano Bruno, and Nicolò Zava. “Epimorphisms and Closure Operators of Categories of Semilattices.” <i>Quaestiones Mathematicae</i>. Taylor &#38; Francis, 2023. <a href=\"https://doi.org/10.2989/16073606.2023.2247731\">https://doi.org/10.2989/16073606.2023.2247731</a>.","mla":"Dikranjan, D., et al. “Epimorphisms and Closure Operators of Categories of Semilattices.” <i>Quaestiones Mathematicae</i>, vol. 46, no. S1, Taylor &#38; Francis, 2023, pp. 191–221, doi:<a href=\"https://doi.org/10.2989/16073606.2023.2247731\">10.2989/16073606.2023.2247731</a>.","short":"D. Dikranjan, A. Giordano Bruno, N. Zava, Quaestiones Mathematicae 46 (2023) 191–221.","ista":"Dikranjan D, Giordano Bruno A, Zava N. 2023. Epimorphisms and closure operators of categories of semilattices. Quaestiones Mathematicae. 46(S1), 191–221."},"year":"2023","abstract":[{"lang":"eng","text":"Motivated by a problem posed in [10], we investigate the closure operators of the category SLatt of join semilattices and its subcategory SLattO of join semilattices with bottom element. In particular, we show that there are only finitely many closure operators of both categories, and provide a complete classification. We use this result to deduce the known fact that epimorphisms of SLatt and SLattO are surjective. We complement the paper with two different proofs of this result using either generators or Isbell’s zigzag theorem."}],"doi":"10.2989/16073606.2023.2247731","day":"01","language":[{"iso":"eng"}],"publication":"Quaestiones Mathematicae","month":"11","oa_version":"None","project":[{"grant_number":"I04245","name":"Algebraic Footprints of Geometric Features in Homology","call_identifier":"FWF","_id":"26AD5D90-B435-11E9-9278-68D0E5697425"}],"user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","status":"public","date_published":"2023-11-01T00:00:00Z","type":"journal_article","publication_identifier":{"eissn":["1727-933X"],"issn":["1607-3606"]}},{"status":"public","user_id":"2DF688A6-F248-11E8-B48F-1D18A9856A87","file":[{"success":1,"access_level":"open_access","relation":"main_file","creator":"dernst","file_id":"14396","checksum":"cdbf90ba4a7ddcb190d37b9e9d4cb9d3","file_size":1026683,"date_created":"2023-10-04T11:46:24Z","file_name":"2023_DiscreteGeometry_Kourimska.pdf","content_type":"application/pdf","date_updated":"2023-10-04T11:46:24Z"}],"oa":1,"publication_identifier":{"issn":["0179-5376"],"eissn":["1432-0444"]},"type":"journal_article","date_published":"2023-07-01T00:00:00Z","tmp":{"legal_code_url":"https://creativecommons.org/licenses/by/4.0/legalcode","short":"CC BY (4.0)","image":"/images/cc_by.png","name":"Creative Commons Attribution 4.0 International Public License (CC-BY 4.0)"},"language":[{"iso":"eng"}],"month":"07","project":[{"name":"Algebraic Footprints of Geometric Features in Homology","grant_number":"I04245","call_identifier":"FWF","_id":"26AD5D90-B435-11E9-9278-68D0E5697425"}],"oa_version":"Published Version","has_accepted_license":"1","publication":"Discrete and Computational Geometry","ddc":["510"],"acknowledgement":"Open access funding provided by the Austrian Science Fund (FWF). This research was supported by the FWF grant, Project number I4245-N35, and by the Deutsche Forschungsgemeinschaft (DFG - German Research Foundation) - Project-ID 195170736 - TRR109.","volume":70,"abstract":[{"lang":"eng","text":"We study a new discretization of the Gaussian curvature for polyhedral surfaces. This discrete Gaussian curvature is defined on each conical singularity of a polyhedral surface as the quotient of the angle defect and the area of the Voronoi cell corresponding to the singularity. We divide polyhedral surfaces into discrete conformal classes using a generalization of discrete conformal equivalence pioneered by Feng Luo. We subsequently show that, in every discrete conformal class, there exists a polyhedral surface with constant discrete Gaussian curvature. We also provide explicit examples to demonstrate that this surface is in general not unique."}],"day":"01","doi":"10.1007/s00454-023-00484-2","external_id":{"isi":["000948148000001"]},"isi":1,"citation":{"ista":"Kourimska H. 2023. Discrete yamabe problem for polyhedral surfaces. Discrete and Computational Geometry. 70, 123–153.","mla":"Kourimska, Hana. “Discrete Yamabe Problem for Polyhedral Surfaces.” <i>Discrete and Computational Geometry</i>, vol. 70, Springer Nature, 2023, pp. 123–53, doi:<a href=\"https://doi.org/10.1007/s00454-023-00484-2\">10.1007/s00454-023-00484-2</a>.","short":"H. Kourimska, Discrete and Computational Geometry 70 (2023) 123–153.","ieee":"H. Kourimska, “Discrete yamabe problem for polyhedral surfaces,” <i>Discrete and Computational Geometry</i>, vol. 70. Springer Nature, pp. 123–153, 2023.","chicago":"Kourimska, Hana. “Discrete Yamabe Problem for Polyhedral Surfaces.” <i>Discrete and Computational Geometry</i>. Springer Nature, 2023. <a href=\"https://doi.org/10.1007/s00454-023-00484-2\">https://doi.org/10.1007/s00454-023-00484-2</a>.","apa":"Kourimska, H. (2023). Discrete yamabe problem for polyhedral surfaces. <i>Discrete and Computational Geometry</i>. Springer Nature. <a href=\"https://doi.org/10.1007/s00454-023-00484-2\">https://doi.org/10.1007/s00454-023-00484-2</a>","ama":"Kourimska H. Discrete yamabe problem for polyhedral surfaces. <i>Discrete and Computational Geometry</i>. 2023;70:123-153. doi:<a href=\"https://doi.org/10.1007/s00454-023-00484-2\">10.1007/s00454-023-00484-2</a>"},"year":"2023","date_updated":"2023-10-04T11:46:48Z","article_type":"original","publisher":"Springer Nature","file_date_updated":"2023-10-04T11:46:24Z","quality_controlled":"1","page":"123-153","intvolume":"        70","title":"Discrete yamabe problem for polyhedral surfaces","article_processing_charge":"Yes (via OA deal)","date_created":"2023-03-26T22:01:09Z","department":[{"_id":"HeEd"}],"publication_status":"published","author":[{"id":"D9B8E14C-3C26-11EA-98F5-1F833DDC885E","first_name":"Hana","last_name":"Kourimska","orcid":"0000-0001-7841-0091","full_name":"Kourimska, Hana"}],"scopus_import":"1","_id":"12764"}]