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Exploring the links between skills and productivity
An assessment of the direct and indirect link between skills and productivity in the context of the Treasury's '5 drivers' of growth. Based on a literature review covering the debate around the extent and nature of the contribution of skills to economic performance, tested through an analysis of labour market data for the East Midlands region
Gravity as elasticity of spacetime: a paradigm to understand horizon thermodynamics and cosmological constant
It is very likely that the quantum description of spacetime is quite
different from what we perceive at large scales, . The
long wave length description of spacetime, based on Einstein's equations, is
similar to the description of a continuum solid made of a large number of
microscopic degrees of freedom. This paradigm provides a novel interpretation
of coordinate transformations as deformations of "spacetime solid" and allows
one to obtain Einstein's equations as a consistency condition in the long
wavelength limit. The entropy contributed by the microscopic degrees of freedom
reduces to a pure surface contribution when Einstein's equations are satisfied.
The horizons arises as "defects" in the "spacetime solid" (in the sense of well
defined singular points) and contributes an entropy which is one quarter of the
horizon area. Finally, the response of the microstructure to vacuum energy
leads to a near cancellation of the cosmological constant, leaving behind a
tiny fluctuation which matches with the observed value.Comment: This essay received an ``honorable mention'' in the 2004 Essay
Competition of the Gravity Research Foundation; accepted for publication in
IJMP
Deconvolution and analysis of wide-angle longwave radiation data from Nimbus 6 Earth radiation budget experiment for the first year
One year of longwave radiation data from July 1975 through June 1976 from the Nimbus 6 satellite Earth radiation budget experiment is analyzed by representing the radiation field by a spherical harmonic expansion. The data are from the wide field of view instrument. Contour maps of the longwave radiation field and spherical harmonic coefficients to degree 12 and order 12 are presented for a 12 month data period
The proposed flatland radar
A flexible very high frequency (VHF) stratosphere-troposphere (ST) radar configured for meteorological research is to be constructed near Urbana, Illinois. Measurement of small vertical velocities associated with synoptic-scale meteorology can be performed. A large Doppler microwave radar (CHILL) is located a few km from the site of the proposed ST radar. Since the microwave radar can measure the location and velocity of hydrometeors and the VHF ST radar can measure clear (or cloudy) air velocities, simultaneous observations by these two radars of stratiform or convective weather systems would provide valuable meteorological information
IV-VI resonant cavity enhanced photodetectors for the midinfrared
A resonant-cavity enhanced detector operating in the mid-infrared at a
wavelength around 3.6 micron is demonstrated. The device is based on a
narrow-gap lead salt heterostructure grown by molecular beam epitaxy. Below 140
K, the photovoltage clearly shows a single narrow cavity resonance, with a
relative line width of only 2 % at 80 K.Comment: 2 figure
MAGMO: Coherent magnetic fields in the star forming regions of the Carina-Sagittarius spiral arm tangent
We present the pilot results of the `MAGMO' project, targeted observations of
ground-state hydroxyl masers towards sites of 6.7-GHz methanol maser emission
in the Carina-Sagittarius spiral arm tangent, Galactic longitudes 280 degrees
to 295 degrees. The `MAGMO' project aims to determine if Galactic magnetic
fields can be traced with Zeeman splitting of masers associated with star
formation. Pilot observations of 23 sites of methanol maser emission were made,
with the detection of ground-state hydroxyl masers towards 11 of these and six
additional offset sites. Of these 17 sites, nine are new detections of sites of
1665-MHz maser emission, three of them accompanied by 1667-MHz emission. More
than 70% of the maser features have significant circular polarization, whilst
only ~10% have significant linear polarization (although some features with up
to 100% linear polarization are found). We find 11 Zeeman pairs across six
sites of high-mass star formation with implied magnetic field strengths between
-1.5 mG and +3.8 mG and a median field strength of +1.6 mG. Our measurements of
Zeeman splitting imply that a coherent field orientation is experienced by the
maser sites across a distance of 5.3+/-2.0 kpc within the Carina-Sagittarius
spiral arm tangent.Comment: 19 pages, 13 figures, accepted for publication in MNRA
Regenerable adsorbent study
Thin film solid regenerable adsorbent for use with sorber plate to determine gase
Cooperative Chiral Order in Copolymers of Chiral and Achiral Units
Polyisocyanates can be synthesized with chiral and achiral pendant groups
distributed randomly along the chains. The overall chiral order, measured by
optical activity, is strongly cooperative and depends sensitively on the
concentration of chiral pendant groups. To explain this cooperative chiral
order theoretically, we map the random copolymer onto the one-dimensional
random-field Ising model. We show that the optical activity as a function of
composition is well-described by the predictions of this theory.Comment: 13 pages, including 3 postscript figures, uses REVTeX 3.0 and
epsf.st
A robust pseudo-inverse spectral filter applied to the Earth Radiation Budget Experiment (ERBE) scanning channels
Computer simulations of a least squares estimator operating on the ERBE scanning channels are discussed. The estimator is designed to minimize the errors produced by nonideal spectral response to spectrally varying and uncertain radiant input. The three ERBE scanning channels cover a shortwave band a longwave band and a ""total'' band from which the pseudo inverse spectral filter estimates the radiance components in the shortwave band and a longwave band. The radiance estimator draws on instantaneous field of view (IFOV) scene type information supplied by another algorithm of the ERBE software, and on a priori probabilistic models of the responses of the scanning channels to the IFOV scene types for given Sun scene spacecraft geometry. It is found that the pseudoinverse spectral filter is stable, tolerant of errors in scene identification and in channel response modeling, and, in the absence of such errors, yields minimum variance and essentially unbiased radiance estimates
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