On the role of the chaotic velocity in relativistic kinetic theory

In this paper we revisit the concept of chaotic velocity within the context of relativistic kinetic theory. Its importance as the key ingredient which allows to clearly distinguish convective and dissipative effects is discussed to some detail. Also, by addressing the case of the two component mixture, the relevance of the barycentric comoving frame is established and thus the convenience for the introduction of peculiar velocities for each species. The fact that the decomposition of molecular velocity in systematic and peculiar components does not alter the covariance of the theory is emphasized. Moreover, we show that within an equivalent decomposition into space-like and time-like tensors, based on a generalization of the relative velocity concept, the Lorentz factor for the chaotic velocity can be expressed explicitly as an invariant quantity. This idea, based on Ellis' theorem, allows to foresee a natural generalization to the general relativistic case.Comment: 12 pages, 2 figure

Relaxation time for the temperature in a dilute binary mixture from classical kinetic theory

The system of our interest is a dilute binary mixture, in which we consider that the species have different temperatures as an initial condition. To study their time evolution, we use the full version of the Boltzmann equation, under the hypothesis of partial local equilibrium for both species. Neither a diffusion force nor mass diffusion appears in the system. We also estimate the time in which the temperatures of the components reach the full local equilibrium. In solving the Boltzmann equation, we imposed no assumptions on the collision term. We work out its solution by using the well known Chapman-Enskog method to first order in the gradients. The time in which the temperatures relax is obtained following Landau's original idea. The result is that the relaxation time for the temperatures is much smaller than the characteristic hydrodynamical times but greater than a collisional time. The main conclusion is that there is no need to study binary mixtures with different temperatures when hydrodynamical properties are sought

A Preliminary Review of Eye Tracking Research in Interpreting Studies: Retrospect and Prospects

The field of Interpreting Studies (IS) has witnessed an exponential increase in the development of new data-gathering techniques aimed at investigating some of the underlying cognitive and psychological processes.The present article provides a preliminary look into research studies applying eye tracking technology in the field of IS over the past few decades. The present study also aims at exploring the theoretical basis for different applications of eye tracking equipment in the investigation of the cognitive processes underlying interpreting by analyzing empirical research studies related to cognitive aspects of translation. The sampled studies are analyzed in terms of the contribution they provide for the joint development of eye tracking research in IS, in terms of the methodology used and the way data are processed and presented.Finally, the present article concludes with a discussion on future research focusing on possible developments and applications of eye tracking to authentic interpreting situational contexts. The final section presents new challenges and opportunities for unexplored applications of eye tracking in the field of IS. It is argued that interdisciplinary approaches can show the full range of possibilities of eye tracking research in the field of IS

A Preliminary Review of Neurolinguistics Research in Simultaneous Interpreting (SI)

The present review article, with no pretense of being exhaustive, aims at shedding light on some of the major empirical studies conducted in recent years in Simultaneous Interpreting (SI) from a neurolinguistics point of view.Some of the issues that will be covered include the definition and development of expertise in SI, neuronal adaptation and the cognitive complexity of SI. The present preliminary review will end with some questions that future research could focus on and, hopefully, provide some answers to

Entropy Production in Relativistic Binary Mixtures

In this paper we calculate the entropy production of a relativistic binary mixture of inert dilute gases using kinetic theory. For this purpose we use the covariant form of Boltzmann's equation which, when suitably transformed, yields a formal expression for such quantity. Its physical meaning is extracted when the distribution function is expanded in the gradients using the well-known Chapman-Enskog method. Retaining the terms to first order, consistently with Linear Irreversible Thermodynamics we show that indeed, the entropy production can be expressed as a bilinear form of products between the fluxes and their corresponding forces. The implications of this result are thoroughly discussed

Ucraina: alla ricerca di una nuova identità condivisa?

UCRAINA: ALLA RICERCA DI UNA NUOVA IDENTITA’ CONDIVISA? In questo elaborato viene trattato il tema della crisi ucraina, non limitando però l’analisi alle sole vicende intercorse tra la fine del 2013 e tutto il 2014, comunque ben consapevoli che gli scontri siano ancora in corso nelle regioni orientali, ma adottando una prospettiva di più ampio spettro per cercare di comprendere le cause che hanno portato alla situazione attuale di impasse. Il risultato è quindi una raccolta di approfondimenti di diverse tematiche, legate fra loro da un filo comune, quello dell’identità nazionale, attraverso il quale si cerca inoltre di fornire una prospettiva di pace per il futuro. Nel primo capitolo, che funge da introduzione e, a seconda del punto di vista, da punto di partenza o di arrivo delle successive analisi, vengono descritte le diverse fasi delle manifestazioni e degli scontri avvenuti in Ucraina, mentre in quelli successivi viene utilizzato di volta in volta un diverso approccio: storico, politico, economico, sociale, culturale. Nel riportare gli avvenimenti salienti sono stati analizzati inoltre i diversi attori in gioco, cercando di stabilirne l’identità, gli scopi nel breve e medio-lungo periodo e, seppur con notevole difficoltà, l’appoggio che essi ricevettero dalla popolazione scesa in piazza. Le riflessioni di carattere generale combinano i diversi singoli aspetti analizzati e collegati tra loro dalla chiave di lettura dell’identità, vista come possibile spiegazione di fondo delle vicende della crisi scoppiata nel 2014 e come elemento decisivo nella costruzione di un futuro migliore per l’Ucraina e la sua popolazione. Il limite principale di questa prospettiva riguarda però l’effettiva volontà delle parti in causa: risulta infatti che l’idea di una (nuova) identità ucraina comune non sia condivisa da tutte le fasce della popolazione

El principio de proporcionalidad en las restricciones al descubrimiento probatorio ante la CPI. Estado del arte, críticas y alternativas

This paper shows the role and development of the principle of pro­portionality in authorizing disclosure restrictions at the icc. The concept and normative basis of these figures in this High Court is studied with the aim to achieve this objective. Subsequently, the contact points between these institu­tions are analyzed in order to get a more complete understanding of them, so that a critical analysis of the Court’s discourse is possible. After that, the state of the art about this particular use of the principle of proportionality in the Court’s jurisprudence will be indicated. Finally, some issues of this develop­ment are presented, and a series of solutions are proposed.Este texto muestra la función y el desarrollo del principio de propor­cionalidad en el establecimiento o autorización de las restricciones al descubri­miento probatorio en la cpi. Para alcanzar este objetivo se estudia el concepto y fundamento normativo de estas figuras en el alto tribunal. Posteriormente, se analizan los puntos de contacto entre las instituciones que aquí convergen con la finalidad de lograr un entendimiento más completo de ellas, de manera que sea posible un análisis crítico del discurso de la Corte. Acto seguido se procede a señalar el estado del arte de este particular uso del principio de pro­porcionalidad en la jurisprudencia de este tribunal. Finalmente, se presentan algunas problemáticas de las que adolece este desarrollo y se propone una serie de soluciones a ellas