40,340 research outputs found
The development of the secondary vocational curriculum in a northern local authority in England
This paper reports on the findings from the evaluation of two projects directed at improving the vocational provision in a Northern Local Authority in England during 2006. The two projects are: Pathways to Success - partly funded by the European Social Fund and Rotherham Ready - with the evaluation funded by the Regional Development Agency, Yorkshire Forward. The evaluation of the two projects had different but overlapping intentions that reflect each project's contribution to the development of the vocational curriculum 14-16 in the local authority. Rotherham Ready has been characterised as a Learning-oriented evaluation whereas Pathways to Success has followed a more traditional evaluation model with more attention given to outputs and the achievements of pupils. However ultimately both investigate the change in culture within schools as they promote a more vocational curriculum for 14-16 year old students</p
Birefringent Electroweak Textures
The behaviour of electromagnetic waves propagating through an electroweak
homilia string network is examined. This string network is topologically stable
as a cosmic texture, and is characterized by the spatial variation of the
isospin rotation of the Higgs field. As a consequence the photon field couples
to the intermediate vector bosons, producing a finite range electromagnetic
field. It is found that the propagation speed of the photon depends on its
polarization vector, whence an homilia string network acts as a birefringent
medium. We estimate the birefringent scale for this texture and show that it
depends on the frequency of the electromagnetic wave and the length scale of
the homilia string network.Comment: 10 page
SVM-based texture classification in optical coherence tomography
This paper describes a new method for automated texture classification for glaucoma detection using high resolution retinal Optical Coherence Tomography (OCT). OCT is a non-invasive technique that produces cross-sectional imagery of ocular tissue. Here, we exploit information from OCT im-ages, specifically the inner retinal layer thickness and speckle patterns, to detect glaucoma. The proposed method relies on support vector machines (SVM), while principal component analysis (PCA) is also employed to improve classification performance. Results show that texture features can improve classification accuracy over what is achieved using only layer thickness as existing methods currently do. Index Terms — classification, support vector machine, optical coherence tomography, texture 1
Motion of a condensate in a shaken and vibrating harmonic trap
The dynamics of a Bose-Einstein condensate (BEC) in a time-dependent harmonic
trapping potential is determined for arbitrary variations of the position of
the center of the trap and its frequencies. The dynamics of the BEC wavepacket
is soliton-like. The motion of the center of the wavepacket, and the spatially
and temporally dependent phase (which affects the coherence properties of the
BEC) multiplying the soliton-like part of the wavepacket, are analytically
determined.Comment: Accepted for publication in J. Phys. B: At Mol Opt Phy
Pathways to "opportunity and excellence": collaborative curriculum innovation in South Yorkshire
This paper reports on two aspects of a large-scale curriculum project currently taking place in four LEAs in South Yorkshire. The first of these is concerned with the positive and negative influences on effective curriculum innovation and is addressed from the perspective of the LEA project managers who are managing the delivery of the project in the region's schools. The second aspect considers what the pupils (Year 10, age 14-15) think about the new learning opportunities. The project is set in the context of regional regeneration. The paper concludes that the extremely positive responses from the sample of pupils in all three strands of the programme indicate that the greater emphasis on vocational work and work experience in schools is having a strong motivational effect on pupils who are responding with improved attendance, behaviour and achievement.</p
Star formation rates and chemical abundances of emission line galaxies in intermediate-redshift clusters
We examine the evolutionary status of luminous, star-forming galaxies in
intermediate-redshift clusters by considering their star formation rates and
the chemical and ionsiation properties of their interstellar emitting gas. Our
sample consists of 17 massive, star-forming, mostly disk galaxies with
M_{B}<-20, in clusters with redshifts in the range 0.31< z <0.59, with a median
of =0.42. We compare these galaxies with the identically selected and
analysed intermediate-redshift field sample of Mouhcine et al. (2006), and with
local galaxies from the Nearby Field Galaxy Survey of Jansen et al. (2000).
From our optical spectra we measure the equivalent widths of OII, Hbeta and
OIII emission lines to determine diagnostic line ratios, oxygen abundances, and
extinction-corrected star formation rates. The star-forming galaxies in
intermediate-redshift clusters display emission line equivalent widths which
are, on average, significantly smaller than measured for field galaxies at
comparable redshifts. However, a contrasting fraction of our cluster galaxies
have equivalent widths similar to the highest observed in the field. This
tentatively suggests a bimodality in the star-formation rates per unit
luminosity for galaxies in distant clusters. We find no evidence for further
bimodalities, or differences between our cluster and field samples, when
examining additional diagnostics and the oxygen abundances of our galaxies.
This maybe because no such differences exist, perhaps because the cluster
galaxies which still display signs of star-formation have recently arrived from
the field. In order to examine this topic with more certainty, and to further
investigate the way in which any disparity varies as a function of cluster
properties, larger spectroscopic samples are needed.Comment: 10 pages, 6 figures, MNRAS in pres
Implementation of a local principal curves algorithm for neutrino interaction reconstruction in a liquid argon volume
A local principal curve algorithm has been implemented in three dimensions
for automated track and shower reconstruction of neutrino interactions in a
liquid argon time projection chamber. We present details of the algorithm and
characterise its performance on simulated data sets.Comment: 14 pages, 17 figures; typing correction to Eq 5, the definition of
the local covariance matri
Microlensing of the Lensed Quasar SDSS0924+0219
We analyze V, I and H band HST images and two seasons of R-band monitoring
data for the gravitationally lensed quasar SDSS0924+0219. We clearly see that
image D is a point-source image of the quasar at the center of its host galaxy.
We can easily track the host galaxy of the quasar close to image D because
microlensing has provided a natural coronograph that suppresses the flux of the
quasar image by roughly an order of magnitude. We observe low amplitude,
uncorrelated variability between the four quasar images due to microlensing,
but no correlated variations that could be used to measure a time delay. Monte
Carlo models of the microlensing variability provide estimates of the mean
stellar mass in the lens galaxy (0.02 Msun < M < 1.0 Msun), the accretion disk
size (the disk temperature is 5 x 10^4 K at 3.0 x 10^14 cm < rs < 1.4 x 10^15
cm), and the black hole mass (2.0 x 10^7 Msun < MBH \eta_{0.1}^{-1/2}
(L/LE)^{1/2} < 3.3 x 10^8 Msun), all at 68% confidence. The black hole mass
estimate based on microlensing is consistent with an estimate of MBH = 7.3 +-
2.4 x 10^7 Msun from the MgII emission line width. If we extrapolate the
best-fitting light curve models into the future, we expect the the flux of
images A and B to remain relatively stable and images C and D to brighten. In
particular, we estimate that image D has a roughly 12% probability of
brightening by a factor of two during the next year and a 45% probability of
brightening by an order of magnitude over the next decade.Comment: v.2 incorporates referee's comments and corrects two errors in the
original manuscript. 28 pages, 10 figures, published in Ap
Soft Phase Lags of Pulsed Emission from the Millisecond X-ray Pulsar SAX J1808.4-3658
We report the discovery of phase shifts between X-ray pulses at different
energies in the newly discovered millisecond (ms) X-ray pulsar SAX
J1808.4-3658. The results show that low-energy pulses lag high-energy pulses by
as much as 0.2 ms (or 8% of the pulse period). The measurements
were made in two different ways: (1) computing cross power spectra between
different energy bands, and (2) cross-correlating the folded pulse profiles in
different energy bands; consistent results were obtained. We speculate that the
observed soft lags might be related to the lateral expansion and subsequent
cooling of a ``hot spot'' on the neutron star surface in which the pulsed X-ray
emission originates. Also presented is the possibility of producing soft lags
via Compton down scattering of hard X-ray photons from the hot spot in the cool
surrounding atmosphere. We will discuss possible X-ray production mechanisms
for SAX J1808.4-3658 and constraints on the emission environment, based on the
observed soft lags, pulse profiles, and energy spectrum.Comment: 11 pages, including four figures. To appear in ApJ Letter
ADOPTION OF DIGITAL TWIN WITHIN THE DEPARTMENT OF THE NAVY
Digital twins have the potential to support the decision-makers that design, build, operate, and maintain the platforms that the Department of the Navy (DON) relies upon to conduct naval operations. However, the thin body of knowledge on digital twins presents a challenge for the DON as the range of applications and risks associated with onboarding digital twins are still unclear. This thesis conducts a qualitative technology assessment to determine the effects that adopting digital twins has on the DON’s enterprise architecture. Analysis of an enterprise-wide adoption identifies opportunities and risks of digital twins within the context of the DON’s strategy, processes, people, technology, cyber security, and risk management. The business value provided by digital twins is principally dependent upon the aggregate risk value of the physical platform and the fidelity and frequency of the digital twin’s synchronizations.Captain, United States Marine CorpsCaptain, United States Marine CorpsApproved for public release. Distribution is unlimited
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