5,469 research outputs found
Possibility of Turbulence from a Post-Navier-Stokes Equation
We introduce corrections to the Navier-Stokes equation arising from the
transitions between molecular states and the injection of external energy. In
the simplest application of the proposed post Navier-Stokes equation, we find a
multi-valued velocity field and the immediate possibility of velocity reversal,
both features of turbulence
Living standards during previous recessions
The current recession is the first that the UK has experienced since the early 1990s. Much has changed since then, and society's collective memory of who fared worst during previous recessions seems likely to have faded. Many workers in their 20s or early 30s have not experienced a recession during their working lives - including both authors of this report, one of whom had just started secondary school at the end of the last recession and the other of whom had just started junior school. This Briefing Note thus aims to document the course of average living standards, and those of particular subgroups in society, during the previous three UK recessions. It will also show what happened to measures of poverty and inequality during these periods
Poverty and inequality in the UK: 2007
This Briefing Note provides an update on trends in living standards, income inequality and poverty. It uses the same approach to measuring income and poverty as the government employs in its Households Below Average Income (HBAI) publication. The analysis is based on the latest HBAI figures (published on 27 March 2007), providing information about incomes up to the year 2005-06. The measure of income used is net household weekly income, which has been adjusted to take account of family size ('equivalised'). The income amounts provided below are expressed as the equivalent for a couple with no children, and all changes given are in real terms (i.e. after adjusting for inflation). For the first time in recent years, data are available for the whole of the United Kingdom, not just Great Britain, but data for Northern Ireland are only available from 2002-03. Some comparisons over time are provided for Great Britain only, but others will compare statistics for GB before 2002-03 with those for the UK afterwards.
PLEASE NOTE: On 23 April 2007, the Department for Work and Pensions announced that an error had occurred when producing the latest Households Below Average Income publication. This Briefing Note was based on the same dataset and therefore suffers from similar errors. In response to revisions announced by the DWP in May 2007, we have now updated our findings in a revised press release and have produced a revised summary
On Educational Performance Measures
Quantitative school performance measures (QPMs) are playing an ever larger role in education systems on both sides of the Atlantic. In this paper we outline the rationale for the use of such measures in education, review the literature relating to several important problems associated with their use, and argue that they nonetheless have a positive role to play in improving the educational quality. We delineate several institutional reforms which would help schools to respond "positively" to QPMs, emphasizing the importance of agents' flexibility to change the way they work, and the importance of a sound knowledge base regarding "what works" in raising attainment. We suggest that the present institutional setups in both England and the US too often hold schools accountable for outcomes over which they have little control â but that such problems are far from insurmountable.performance measures, education incentives, school quality
The BL-Lac gamma-ray blazar PKS 0447-439 as a probable member of a group of galaxies at z=0.343
The BL-Lac blazar PKS 0447-439 is one of the brightest HE gamma-ray sources
that were first detected by Fermi-LAT. It was also detected by H.E.S.S. at VHE
gamma-rays, which allowed constraining the redshift of PKS 0447-439 by
considering the attenuation caused by gamma-ray interactions with ambient
photons in the extragalactic background light (EBL). This constraint agreed
with color-magnitude and spectroscopic redshift constraints (0.179 < z < 0.56),
Recently, however, a much higher redshift was proposed for this blazar (z >
1.2). This value was debated because if true, it would imply either that the
relevant absorption processes of gamma-rays are not well understood or that the
EBL is dramatically different from what is believed today. This high redshift
was not confirmed by three independent new spectroscopic observations at high
signal-to-noise ratios.
Given that BL-Lac are typically hosted by elliptical galaxies, which in turn
are associated with groups, we aim to find the host group of galaxies of PKS
0447-439. The ultimate goal is to estimate a redshift for this blazar.
Spectra of twenty-one objects in the field of view of PKS 0447-439 were
obtained with the Gemini Multi-Object Spectrograph. Based on the redshifts and
coordinates of these galaxies, we searched for groups of galaxies. Using a deep
catalog of groups, we studied the probability of finding by chance a group of
galaxies in the line of sight of PKS 0447-439.
We identified a group of galaxies that was not previously cataloged at z =
0.343 with seven members, a virial radius of 0.42 Mpc, and a velocity
dispersion of 622 km s^-1. We found that the probability of the host galaxy of
PKS 0447-439 to be a member of the new group is >= 97%. Therefore, we propose
to adopt z = 0.343 +- 0.002 as the most likely redshift for PKS 0447-439.Comment: Accepted for publication in A&
Poverty and Inequality in the UK: 2008
In this Commentary, we assess the changes to average incomes, inequality and poverty that have occurred under the first 10 years of the Labour government, with a particular focus on the changes that have occurred in the latest year of data. This analysis is based upon the latest figures from the DWP's Households Below Average Income (HBAI) series, published on 10 June 2008 (Department for Work and Pensions, 2008c). The HBAI series takes household income as its measure of living standards and is derived from the Family Resources Survey, a survey of around 28,000 households in the United Kingdom that asks detailed questions about income from a range of sources
Poverty and inequality in the UK: 2009
In this Commentary, we assess the changes to average incomes, inequality and poverty that have occurred since Labour came to power in 1997, with a particular focus on the changes that have occurred in the latest year of data. This analysis is based upon the latest figures from the DWP's Households Below Average Income (HBAI) series, published on 7 May 2009 (Department for Work and Pensions, 2009). The HBAI series takes household income as its measure of living standards, and is derived from the Family Resources Survey, a survey of around 25,000 households in the United Kingdom that asks detailed questions about income from a range of sources
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