Beyond locutionary denotations: exploring trust between practitioners and policy

This study reports the findings of a research on the trust relationship between practitioners in the Skills for Life (SfL) area and the policy that informs their practice. The exploration of this relationship was premised on an extended notion of trust relationship which draws from the Speech Act theory of Austin (1962; Searle 1969; Kissine 2008), leading to the claim that the existence of different layers of imports in textual analysis makes it possible for a trust relationship to exist between the human/physical and the non human/non physical. The study found that the majority of practitioners in the SfL field trust policy to deliver its inherent policy only to a limited extent. Amongst others, the study identified the impact of the perlocutionary import of policy text on practitioners as a viable reason for this limited level of trust. Such perlocutionary imports, it also found, have adverse impact on practitioners who are considered to have drawn from previous experience to mediate the import of contemporary policies

Pumping in quantum dots and non-Abelian matrix Berry phases

We have investigated pumping in quantum dots from the perspective of non-Abelian (matrix) Berry phases by solving the time dependent Schr{\"o}dinger equation exactly for adiabatic changes. Our results demonstrate that a pumped charge is related to the presence of a finite matrix Berry phase. When consecutive adiabatic cycles are performed the pumped charge of each cycle is different from the previous ones

‘Oh you don’t want asylum seekers, oh you’re just racist’: A discursive analysis of discussions about whether it’s racist to oppose asylum seeking

ABSTRACT In this article, we explore how speakers discuss whether or not it is racist to oppose asylum seekers. A discourse analysis is conducted on the parts of a corpus of data collected from focus groups with undergraduate students talking about asylum seeking in which they were asked if it is racist to oppose asylum. It is shown that speakers use the word ‘just’ as part of a contrast structure which is used to present a topic as self-evidently unreasonable. While some participants orient to the taboo against prejudice, it is shown that there is also an orientation to the idea that accusations of racism are unreasonable and that opposition to asylum is usually based on practical and economic reasons rather than racism. These findings are discussed in light of the growing literature surrounding the changing nature of race talk and new taboos on accusations of racism

Boundaries and Prototypes in Categorizing Direction

Projective terms such as left, right, front, back are conceptually interesting due to their flexibility of contextual usage and their central relevance to human spatial cognition. Their default acceptability areas are well known, with prototypical axes representing their most central usage and decreasing acceptability away from the axes. Previous research has shown these axes to be boundaries in certain non-linguistic tasks, indicating an inverse relationship between linguistic and non-linguistic direction concepts under specific circumstances. Given this striking mismatch, our study asks how such inverse non-linguistic concepts are represented in language, as well as how people describe their categorization. Our findings highlight two distinct grouping strategies reminiscent of theories of human categorization: prototype based or boundary based. These lead to different linguistic as well as non-linguistic patterns

Gamma-Ray Bursts: The Underlying Model

A pedagogical derivation is presented of the ``fireball'' model of gamma-ray bursts, according to which the observable effects are due to the dissipation of the kinetic energy of a relativistically expanding wind, a ``fireball.'' The main open questions are emphasized, and key afterglow observations, that provide support for this model, are briefly discussed. The relativistic outflow is, most likely, driven by the accretion of a fraction of a solar mass onto a newly born (few) solar mass black hole. The observed radiation is produced once the plasma has expanded to a scale much larger than that of the underlying ``engine,'' and is therefore largely independent of the details of the progenitor, whose gravitational collapse leads to fireball formation. Several progenitor scenarios, and the prospects for discrimination among them using future observations, are discussed. The production in gamma- ray burst fireballs of high energy protons and neutrinos, and the implications of burst neutrino detection by kilometer-scale telescopes under construction, are briefly discussed.Comment: In "Supernovae and Gamma Ray Bursters", ed. K. W. Weiler, Lecture Notes in Physics, Springer-Verlag (in press); 26 pages, 2 figure

MCMC implementation for Bayesian hidden semi-Markov models with illustrative applications

Copyright © Springer 2013. The final publication is available at Springer via http://dx.doi.org/10.1007/s11222-013-9399-zHidden Markov models (HMMs) are flexible, well established models useful in a diverse range of applications. However, one potential limitation of such models lies in their inability to explicitly structure the holding times of each hidden state. Hidden semi-Markov models (HSMMs) are more useful in the latter respect as they incorporate additional temporal structure by explicit modelling of the holding times. However, HSMMs have generally received less attention in the literature, mainly due to their intensive computational requirements. Here a Bayesian implementation of HSMMs is presented. Recursive algorithms are proposed in conjunction with Metropolis-Hastings in such a way as to avoid sampling from the distribution of the hidden state sequence in the MCMC sampler. This provides a computationally tractable estimation framework for HSMMs avoiding the limitations associated with the conventional EM algorithm regarding model flexibility. Performance of the proposed implementation is demonstrated through simulation experiments as well as an illustrative application relating to recurrent failures in a network of underground water pipes where random effects are also included into the HSMM to allow for pipe heterogeneity