The use of well-nested linear context-free rewriting systems has been empirically motivated for modeling of the syntax of languages with discontinuous constituents or relatively free word order. We present a chart-based parsing algorithm that asymptotically improves the known running time upper bound for this class of rewriting systems. Our result is obtained through a linear space construction...

A subpansive tree is a rooted tree that gives a partial order of nonterminal symbols of a context-free grammar. We formalize subpansive trees as background knowledge of CFGs, and investigate query learning of CFGs with the help of subpansive trees. We show a restricted class of CFGs, which we call hierarchical CFGs, is efficiently learnable, while it is unlikely to be polynomial-time predictable.

A dynamic k-coloring of a graph G is a proper k-coloring of the vertices of G such that every vertex of degree at least 2 in G will be adjacent to vertices with at least 2 different colors. The smallest number k for which a graph G can have a dynamic k-coloring is the dynamic chromatic number, denoted by χd(G). In this paper, we investigate the dynamic 3-colorings of claw-free graphs. First, we...

We present a polynomial-time algorithm that given two independent sets in a claw-free graph G decides whether one can be transformed into the other by a sequence of elementary steps. Each elementary step is to remove a vertex v from the current independent set S in the sequence and to add a new vertex w (not in S) such that the set S−v+w is independent

We develop a resummed high-temperature expansion for lattice spin systems with long range interactions, in models where the free energy is not, in general, analytic. We establish uniqueness of the Gibbs state and exponential decay of the correlation functions. Then, we apply this expansion to the Perron-Frobenius operator of weakly coupled map lattices.

The phase separation process which follows a sudden quench inside the coexistence region is considered for a binary fluid subjected to an applied shear flow. This issue is studied in the framework of the convection-diffusion equation based on a Ginzburg-Landau free energy functional in the approximation scheme introduced by Bray and Humayun [Phys.Rev.Lett. 68, 1559, (1992)]. After an early stag...

In this paper we present a simple linear-time algorithm constructing a context-free grammar of size O(g log(N/g)) for the input string, where N is the size of the input string and g the size of the optimal grammar generating this string. The algorithm works for arbitrary size alphabets, but the running time is linear assuming that the alphabet Σ of the input string can be identified with number...

We extend the results of Ref. [1] to noncommutative gauge theories at finite temperature. In particular, by making use of the background field method, we analyze renormalization issues and the high-temperature asymptotics of the one-loop Euclidean free energy of the noncommutative U(1) gauge model within imaginary time formalism. As a by-product, the heat trace of the non-minimal photon kinetic...

In Corpus-Based Machine Translation, the search space of the translation candidates for a given input sentence is often defined by a set of (cyclefree) context-free grammar rules. This happens naturally in Syntax-Based Machine Translation and Hierarchical Phrase-Based Machine Translation (where the representation will be the set of the target-side half of the synchronous rules used to parse the...

We review non-perturbative static potentials commonly used in potential models for quarkonia at finite T . Potentials derived from Polyakov loop correlators are shown to be inappropriate for this purpose. The qq̄ free energy is physical but has the wrong spatial decay and perturbative limit. The so-called singlet free energy is gauge dependent and unphysical. An appropriate static real time pote...