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Schemes and estimates for the long-time numerical solution of Maxwell’s equations for Lorentz metamaterials
We consider time domain formulations of Maxwell's equations for the Lorentz model for metamaterials. The field equations are considered in two different forms which have either six or four unknown vector fields. In each case we use arguments tuned to the physical laws to derive data-stability estimates which do not require Gronwall's inequality. The resulting estimates are, in this sense, sharp. We also give fully discrete formulations for each case and extend the sharp data-stability to these. Since the physical problem is linear it follows (and we show this with examples) that this stability property is also reflected in the constants appearing in the a priori error bounds. By removing the exponential growth in time from these estimates we conclude that these schemes can be used with confidence for the long-time numerical simulation of Lorentz metamaterials.This work was supported in part by NSFC Project 11271310, NSF grant DMS-1416742, and a grant from
the Simons Foundation (#281296 to Li), in part by scheme 4 London Mathematical Society funding and in part
by the Engineering and Physical Sciences Research Council (EP/H011072/1 to Shaw)
Analysis of carbon dioxide bands near 2.2 micrometers
Carbon dioxide is one of the more important atmospheric infrared-absorbing gases due to its relatively high, and increasing, concentration. The spectral parameters of its bands are required for understanding radiative heat transfer in the atmosphere. The line intensities, positions, line half-widths, rotational constants, and band centers of three overlapping bands of CO2 near 2.2 microns are presented. Non-linear least squares (NLLS) regression procedures were employed to determine these parameters
Celebrity capital in the political field: Russell Brand's migration from stand-up comedy to Newsnight
Our case study of charismatic celebrity comedian Russell Brand’s turn to political activism uses Bourdieu’s field theory to understand the process of celebrity migration across social fields. We investigate how Brand’s capital as a celebrity performer, storyteller and self-publicist translated from comedy to politics. To judge how this worked in practice, we analysed the comedic strategies used in his stand up show Messiah Complex and a Conversational Analysis of his notorious interview with Jeremy Paxman on the BBC’s flagship current affairs programme Newsnight . We argue that Brand was able to secure political legitimacy by creatively constituting himself as an authentic anti-austerity spokesperson for the disenfranchised left in UK. In order to do so he repurposed his celebrity capital to political ends and successfully deployed the cultural and social capital he had developed as a celebrity comedian to secure widespread engagement with his media performances
Device and method for frictionally testing materials for ignitability
Test apparatus for determining ignition characteristics of various metal in oxidizer environments simulating operating conditions for materials is invented. The test apparatus has a chamber through which the oxidizing agent flows, and means for mounting a stationary test sample therein, a powered, rotating shaft in the chamber rigidly mounts a second test sample. The shaft is axially movable to bring the samples into frictional engagement and heated to the ignition point. Instrumentation connected to the apparatus provides for observation of temperatures, pressures, loads on and speeds of the rotating shaft, and torques whereby components of stressed oxygen systems can be selected which will avoid accidental fires under working conditions
The Value of the Cosmological Constant
We make the cosmological constant, {\Lambda}, into a field and restrict the
variations of the action with respect to it by causality. This creates an
additional Einstein constraint equation. It restricts the solutions of the
standard Einstein equations and is the requirement that the cosmological wave
function possess a classical limit. When applied to the Friedmann metric it
requires that the cosmological constant measured today, t_{U}, be {\Lambda} ~
t_{U}^(-2) ~ 10^(-122), as observed. This is the classical value of {\Lambda}
that dominates the wave function of the universe. Our new field equation
determines {\Lambda} in terms of other astronomically measurable quantities.
Specifically, it predicts that the spatial curvature parameter of the universe
is {\Omega}_{k0} \equiv -k/a_(0)^(2)H^2= -0.0055, which will be tested by
Planck Satellite data. Our theory also creates a new picture of self-consistent
quantum cosmological history.Comment: 6 pages. This article received Third Prize in the 2011 Gravity
Research Foundation Awards for Essays on Gravitatio
The limitations of speech control: perceptions of provision of speech-driven environmental controls
This study set out to collect data from assistive technology professionals about their provision of speech-driven environmental control systems. This study is part of a larger study looking at developing a new speech-driven environmental control system
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