arXiv subjects

Stephen Barnett

Publications and source records attributed to Stephen Barnett.

3 recordsLinked to original sources

arXiv2016

Analysing health professionals' learning interactions in online social networks: A social network analysis approach

Online Social Networking may be a way to support health professionals' need for continuous learning through interaction with peers and experts. Understanding and evaluating such learning is important but difficult, and Social Network Analysis (SNA) offers a solution. This paper demonstrates how SNA can be used to study levels of participation as well as the patterns of interactions that take place among health professionals in a large online professional learning network. Our analysis has shown that their learning network is highly centralised and loosely connected. The level of participation is low in general, and most interactions are structured around a small set of users consisting of moderators and core members. The structural patterns of interaction indicates there is a chance of small group learning occurring and requires further investigation to identify those potential learning groups. This first stage of analysis, to be followed by longitudinal study of the dynamics of interaction and complemented by content analysis of their discussion, may contribute to greater sophistication in the analysis and utilisation of new environments for health professional learning.

cs.SI↗

arXiv2016

Comment on "Catalytic Coherence"

Aberg has claimed in a recent Letter," Phys. Rev. Lett. 113, 150402 (2014)", that the coherence of a reservoir can be used repeatedly to perform coherent operations without ever diminishing in power to do so. The claim has particular relevance for quantum thermodynamics because, as shown in "Phys. Rev. Lett. 113, 150402 (2014)", latent energy that is locked by coherence may be extractable without incurring any additional cost. We show here, however, that repeated use of the reservoir gives an overall coherent operation of diminished accuracy and is necessarily accompanied by an increased thermodynamic cost.

quant-ph↗

arXiv2006

Fourier relationship between angular position and optical orbital angular momentum

We demonstrate the Fourier relationship between angular position and angular momentum for a light mode. In particular we measure the distribution of orbital angular momentum states of light that has passed through an aperture and verify that the orbital angular momentum distribution is given by the complex Fourier-transform of the aperture function. We use spatial light modulators, configured as diffractive optical components, to define the initial orbital angular momentum state of the beam, set the defining aperture, and measure the angular momentum spread of the resulting beam. These measurements clearly confirm the Fourier relationship between angular momentum and angular position, even at light intensities corresponding to the single photon level.

physics.optics↗