Jakub Gajarský, Petr Hliněný, Daniel Lokshtanov, Jan Obdržálek, Sebastian Ordyniak, M. S. Ramanujan, Saket Saurabh
备注:
Minor correction, p.5, def. of τ_{s+1}: instead of an induced subdigraph of D_s, we use the appropriate relational structure formed from this subdigrph
Over the past two decades the main focus of research into first-order (FO) model checking algorithms have been sparse relational structures-culminating in the FPT-algorithm by Grohe, Kreutzer and Siebertz for FO model checking of nowhere dense classes of graphs [STOC'14], with dense structures starting to attract attention only recently. Bova, Ganian and Szeider [LICS'14] initiated the study of the complexity of FO model checking on partially ordered sets (posets). Bova, Ganian and Szeider showed that model checking existential FO logic is fixed-parameter tractable (FPT) on posets of bounded width, where the width of a poset is the size of the largest antichain in the poset. The existence of an FPT algorithm for general FO model checking on posets of bounded width, however, remained open. We resolve this question in the positive by giving an algorithm that takes as its input an $n$-element poset $\cal P$ of width $w$ and an FO logic formula $ϕ$, and determines whether $ϕ$ holds on $\cal P$ in time $f(ϕ,w)\cdot n^2$.
Weak Simplicial Bisimilarity and Minimisation for Polyhedral Model Checking
University of Amsterdam(阿姆斯特丹大学);Istituto di Scienza e Tecnologie dell’Informazione “A. Faedo”, Consiglio Nazionale delle Ricerche(意大利国家研究委员会信息科学与技术研究所(A. Faedo));Andrea Razmadze Mathematical Institute, I. Javakhishvili Tbilisi State University(伊万·贾瓦希什维利第比利斯国立大学安德烈·拉兹马泽数学研究所);Eindhoven University of Technology(埃因霍温理工大学)
可识别性定理指出,如果一组有限图可由一元二阶(Monadic Second Order,MSO)语句定义,则它相对于图代数是可识别的,而图宽度的定义是基于图代数的。可识别性是一个代数概念,用同余来定义,也可以用有限自动机来描述所考虑的图。该定理要求MSO图属性的验证,或者等价地,有限二元关系结构上的MSO逻辑的模型检验问题,对于由表示属性的公式和输入图或结构的树宽度(或树宽度)组成的参数是固定参数可处理的(FPT)。相应的算法可以通过飞行自动机来实现,其转换是在飞行中计算的,而不是列表。我们回顾了两个版本的可识别性,我们目前的苍蝇自动机的例子表明,他们也可以计算值附加到图。我们表明,飞自动机与无限的状态集产生一个简单的证明强版本的可识别性定理。这个证明以前没有发表过。
Monadic dependence from reducts, and applications to twin-width of oriented graphs
Université Paris Cité(巴黎西岱大学);CNRS(法国国家科学研究中心);IRIF(信息学研究与综合实验室);Centre d'Analyse et de Mathématique Sociales CNRS UMR 8557(社会分析与数学中心);Southeast University(东南大学);Computer Science Institute of Charles University (IUUK)(查理大学计算机科学研究所)
Characterizations of monadically dependent tree-ordered weakly sparse structures
Université Paris Cité(巴黎西岱大学);CNRS(法国国家科学研究中心);IRIF(信息与随机研究所);Centre d'Analyse et de Mathématique Sociales CNRS UMR 8557(社会分析与数学中心);Southeast University(东南大学);Computer Science Institute of Charles University (IUUK)(查理大学计算机科学研究所);University of Bremen(不来梅大学)