An ω-grammar is a formal grammar used to generateω-words (i.e. infinite length words), while an ω-automaton is an automaton used to recognize ω-words. This paper gives clean and uniform definitions for ω-grammars and ω-automata, provides a systematic study of the generative power of ω-grammars with respect to ω-automata, and presents a complete set of results for various types of ω-grammars and...

We study two-player games played on finite graphs equipped with costs on edges and introduce two winning conditions, cost-parity and cost-Streett, which require bounds on the cost between requests and their responses. Both conditions generalize the corresponding classical omega-regular conditions and the corresponding finitary conditions. For parity games with costs we show that the first playe...

The regular !-languages can be deened by deterministic !-automata with the Rabin acceptance condition, referring to a list of pairs (Ek; Fk) 1km of state sets of the automaton: A successful run should visit some Ek only nitely often but the corresponding Fk innnitely often. If only the non-existence, respectively existence of such visits is required, precisely the Staiger-Wagner deenable !-lang...

In this paper, we are concerned with the following fractional Schrödinger-Poisson system:    (−∆s)u + V (x)u + φu = m(x)|u|q−2|u|+ f(x,u), x ∈ Ω, (−∆t)φ = u2, x ∈ Ω, u = φ = 0, x ∈ ∂Ω, where s,t ∈ (0,1], 2t + 4s > 3, 1 < q < 2 and Ω is a bounded smooth domain of R3, and f(x,u) is linearly bounded in u at infinity. Under some assumptions on m, V and f we obtain the existence of non-trivial so...

In this paper, firstly, we introduce a higher-dimensional analogue of hypergraphs, namely ω-hypergraphs. This notion is thoroughly flexible because unlike ordinary ω-graphs, an n-dimensional edge called an n-cell has many sources and targets. Moreover, cells have polarity, with which pasting of cells is implicitly defined. As examples, we also give some known structures in terms of ω-hypergraph...

Throughout this paper, R will denote a commutative ring with identity and M is a unitary R- module and Z will denote the ring of integers. We introduce the graph Ω(M) of module M with the set of vertices contain all nontrivial non-essential submodules of M. We investigate the interplay between graph-theoretic properties of Ω(M) and algebraic properties of M. Also, we assign the values of natura...

Abstract. A topological group H is called ω -narrow if for every neighbourhood V of it’s identity element there exists a countable set A such that V A = H = AV. A semigroup G is called a generalized group if for any x ∈ G there exists a unique element e(x) ∈ G such that xe(x) = e(x)x = x and for every x ∈ G there exists x − 1 ∈ G such that x − 1x = xx − 1 = e(x). Also le...