Geometrically closed positive varieties of languages

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F00216224%3A14310%2F22%3A00129037" target="_blank" >RIV/00216224:14310/22:00129037 - isvavai.cz</a>

Výsledek na webu

<a href="https://www.sciencedirect.com/science/article/pii/S0890540121000249#" target="_blank" >https://www.sciencedirect.com/science/article/pii/S0890540121000249#</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.1016/j.ic.2021.104709" target="_blank" >10.1016/j.ic.2021.104709</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Geometrically closed positive varieties of languages

Popis výsledku v původním jazyce

A recently introduced operation of geometrical closure on formal languages is investigated from the viewpoint of algebraic language theory. Positive varieties V containing exclusively languages with regular geometrical closure are fully characterised by inclusion of V in W, a known positive variety arising in the study of the commutative closure. It is proved that the geometrical closure of a language from the intersection of W with the variety of all star-free languages SF always falls into RLT, which is introduced as a subvariety of R, the variety of languages recognised by R-trivial monoids. All classes between RLT and W∩SF are thus geometrically closed: for instance, the level 3/2 of the Straubing-Thérien hierarchy, the DA-recognisable languages, or the variety R. It is also shown that W∩SF is the largest geometrically closed positive variety of star-free languages, while there is no largest geometrically closed positive variety of regular languages.

Název v anglickém jazyce

Geometrically closed positive varieties of languages

Popis výsledku anglicky

A recently introduced operation of geometrical closure on formal languages is investigated from the viewpoint of algebraic language theory. Positive varieties V containing exclusively languages with regular geometrical closure are fully characterised by inclusion of V in W, a known positive variety arising in the study of the commutative closure. It is proved that the geometrical closure of a language from the intersection of W with the variety of all star-free languages SF always falls into RLT, which is introduced as a subvariety of R, the variety of languages recognised by R-trivial monoids. All classes between RLT and W∩SF are thus geometrically closed: for instance, the level 3/2 of the Straubing-Thérien hierarchy, the DA-recognisable languages, or the variety R. It is also shown that W∩SF is the largest geometrically closed positive variety of star-free languages, while there is no largest geometrically closed positive variety of regular languages.

Druh

J_imp - Článek v periodiku v databázi Web of Science

CEP obor

—

OECD FORD obor

10201 - Computer sciences, information science, bioinformathics (hardware development to be 2.2, social aspect to be 5.8)

Projekt

<a href="/cs/project/GA19-12790S" target="_blank" >GA19-12790S: Efektivní charakterizace tříd konečných pologrup a formálních jazyků</a><br>

Návaznosti

P - Projekt vyzkumu a vyvoje financovany z verejnych zdroju (s odkazem do CEP)

Rok uplatnění

2022

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Information and Computation

ISSN

0890-5401

e-ISSN

1090-2651

Svazek periodika

288

Číslo periodika v rámci svazku

October

Stát vydavatele periodika

US - Spojené státy americké

Počet stran výsledku

17

Strana od-do

1-17

Kód UT WoS článku

000873951700008

EID výsledku v databázi Scopus

2-s2.0-85101014909