Models to represent linguistic linked data

As the interest of the Semantic Web and computational linguistics communities in linguistic linked data (LLD) keeps increasing and the number of contributions that dwell on LLD rapidly grows, scholars (and linguists in particular) interested in the development of LLD resources sometimes find it difficult to determine which mechanism is suitable for their needs and which challenges have already been addressed. This review seeks to present the state of the art on the models, ontologies and their extensions to represent language resources as LLD by focusing on the nature of the linguistic content they aim to encode. Four basic groups of models are distinguished in this work: models to represent the main elements of lexical resources (group 1), vocabularies developed as extensions to models in group 1 and ontologies that provide more granularity on specific levels of linguistic analysis (group 2), catalogues of linguistic data categories (group 3) and other models such as corpora models or service-oriented ones (group 4). Contributions encompassed in these four groups are described, highlighting their reuse by the community and the modelling challenges that are still to be faced

Novel glassy behavior in a ferromagnetic p-spin model

Recent work has suggested the existence of glassy behavior in a ferromagnetic model with a four-spin interaction. Motivated by these findings, we have studied the dynamics of this model using Monte Carlo simulations with particular attention being paid to two-time quantities. We find that the system shares many features in common with glass forming liquids. In particular, the model exhibits: (i) a very long-lived metastable state, (ii) autocorrelation functions that show stretched exponential relaxation, (iii) a non-equilibrium timescale that appears to diverge at a well defined temperature, and (iv) low temperature aging behaviour characteristic of glasses.Comment: 6 pages, 5 figure

Growing Correlation Length on Cooling Below the Onset of Caging in a Simulated Glass-Forming Liquid

We present a calculation of a fourth-order, time-dependent density correlation function that measures higher-order spatiotemporall correlations of the density of a liquid. From molecular dynamics simulations of a glass-forming Lennard-Jones liquid, we find that the characteristic length scale of this function has a maximum as a function of time which increases steadily beyond the characteristic length of the static pair correlation function $g(r)$ in the temperature range approaching the mode coupling temperature from above

Diffusion and viscosity in a supercooled polydisperse system

We have carried out extensive molecular dynamics simulations of a supercooled polydisperse Lennard-Jones liquid with large variations in temperature at a fixed pressure. The particles in the system are considered to be polydisperse both in size and mass. The temperature dependence of the dynamical properties such as the viscosity ($\eta$) and the self-diffusion coefficients ($D_i$) of different size particles is studied. Both viscosity and diffusion coefficients show super-Arrhenius temperature dependence and fit well to the well-known Vogel-Fulcher-Tammann (VFT) equation. Within the temperature range investigated, the value of the Angell's fragility parameter (D $\approx 1.4$) classifies the present system into a strongly fragile liquid. The critical temperature for diffusion ($T_o^{D_i}$) increases with the size of the particles. The critical temperature for viscosity ($T_o^{\eta}$) is larger than that for the diffusion and a sizeable deviations appear for the smaller size particles implying a decoupling of translational diffusion from viscosity in deeply supercooled liquid. Indeed, the diffusion shows markedly non-Stokesian behavior at low temperatures where a highly nonlinear dependence on size is observed. An inspection of the trajectories of the particles shows that at low temperatures the motions of both the smallest and largest size particles are discontinuous (jump-type). However, the crossover from continuous Brownian to large length hopping motion takes place at shorter time scales for the smaller size particles.Comment: Revtex4, 7 pages, 8 figure

The acquisition of grammatical gender in L1 bilingual Spanish

Producción CientíficaWe analyze the emergence of grammatical gender in the spontaneous longitudinal Spanish production of a set of Spanish/English bilingual twins from the FerFuLice corpus (Fernández Fuertes & Liceras, 2009). We take as a point of departure theoretical accounts on gender assignment and gender concord and previous empirical work on the acquisition of gender by monolinguals and bilinguals. Our study deals with how gender incorporates in the case of L1 Spanish bilinguals; how concord within the determiner phrase (DP) operates; and how monolingual and bilingual Spanish pattern in the same way in this respect. We conclude that DP syntax and the gender concord valuation mechanism are in place from very early stages and that morphology and semantics are not determinant factors in this process.Ministerio de Ciencia e Innovación - FEDER (HUM2007-62213 and BFF2002-00442)Junta de Castilla y León (UV30/02 and VA046A06

Representing Knowledge About Words

Most on-line lexicons contain only semantic information. Semantic information is usually stored elsewhere, in a form consistent with representation of the syntactic information. This paper reports on research toward developing a large on-line lexicon from machine-readable dictionaries, which contains both syntactic and semantic information in uniform style. The fundamental theory is that of one of the relational lexicon; we describe relational lexicons, discuss our extensions to the usual theory of relational lexicons, rehearse very quickly some of the relations we are dealing with, and show how information for some simple entries is stored