8,378 research outputs found
Recommended from our members
Review of equality statistics
The Equality and Human Rights Commission (EHRC) commissioned this review as part of its remit to map the equalities landscape across England, Scotland and Wales. The report examines the extent to which data are available for the following equality strands: sex; ethnicity / race; disability; religion or belief; age; sexual orientation; and also for socio-economic status (social class). The extent to which statistics are available at different levels of geographic classification (UK, GB, England, Scotland and Wales and regional and local areas within this) is investigated. The report addresses the ten domains of equality identified in the equality measurement framework in the Equalities Review.1 These are: Longevity Physical security Health Education Standard of living Productive and valued activities Individual, family and social life Participation, influence and voice Identity, expression and self-respect Legal securit
Recommended from our members
A Technique for Determining the Carrier Phase Differences between Independent GPS Receivers during Scintillation
A method for recovering the carrier phase differences between
pairs of independent GPS receivers has been developed
and demonstrated in truth-model simulations. This
effort is in support of a project that intends to image the disturbed
ionosphere with diffraction tomography techniques
using GPS measurements from large arrays of receivers.
Carrier phase differential GPS techniques, common in surveying
and relative navigation, are employed to determine
the phase relationships between the receivers in the imaging array. Strategies for estimating the absolute carrier phase
disturbances at each receiver are discussed. Simulation results
demonstrate that the system can rapidly detect the onset
of scintillation, identify one non-scintillating reference
signal, and recover the carrier phase differences accurate to
0.1 cycles.Aerospace Engineering and Engineering Mechanic
Thermal fatigue and oxidation data for directionally solidified MAR-M 246 turbine blades
Thermal fatigue and oxidation data were obtained for 11 plasma spray coated and 13 uncoated directionally solidified and single crystal MAR-M 246 blades. Blade coatings on the airfoil included several metal-oxide thermal barrier layers based on Al2O3, Cr2O3, or ZrO2. The 24 turbine blades were tested simultaneously for 3000 cycles in fluidized beds maintained at 950 and 25 C using a symmetrical 360 set thermal cycle. In 3000 cycles, only uncoated turbine blades exhibited cracking on the trailing edge near the platform; 3 of the 13 uncoated blades did not crack. Cracking occurred over the range 400 to 2750 cycles, with single crystal blades indicating the poorest thermal fatigue resistance. Oxidation of the uncoated blades was limited in 3000 cycles. All coatings indicated microscopically visible spalling at the trailing edge radius after 3000 cycles. Severe general spalling on the airfoil was observed for two multilayered coatings
Web 2.0 Projects at Warwick University Library
About 2 years ago at Warwick our senior managers encouraged Academic Support staff to really explore web 2.0 technologies and find out if anything particularly lent itself to supporting library work or marketing. We were given free reign to find out what worked and what suited the library, and what didnât. The following brief overviews cover only four of the projects that have been running since then. We have also investigated much more, including Twitter, Google Documents, wiki reading lists, You-Tube and more, but we couldnât possibly fit it all in here. The brief articles below are just to give a taste of the kind of projects we have worked on. There are many more members of staff involved and many more web 2.0 adventures underway..
GPS Carrier Tracking Loop Performance in the presence of Ionospheric Scintillations
The performance of several GPS carrier tracking loops
is evaluated using wideband GPS data recorded during
strong ionospheric scintillations. The aim of this study is
to determine the loop structures and parameters that enable
good phase tracking during the power fades and phase
dynamics induced by scintillations. Constant-bandwidth
and variable-bandwidth loops are studied using theoretical
models, simulation, and tests with actual GPS signals.
Constant-bandwidth loops with loop bandwidths near 15
Hz are shown to lose phase lock during scintillations. Use
of the decision-directed discriminator reduces the carrier
lock threshold by âŒ1 dB relative to the arctangent and conventional Costas discriminators. A proposed variablebandwidth
loop based on a Kalman filter reduces the carrier
lock threshold by more than 7 dB compared to a 15-Hz
constant-bandwidth loop. The Kalman filter-based strategy
employs a soft-decision discriminator, explicitly models
the effects of receiver clock noise, and optimally adapts
the loop bandwidth to the carrier-to-noise ratio. In extensive
simulation and in tests using actual wideband GPS
data, the Kalman filter PLL demonstrates improved cycle
slip immunity relative to constant bandwidth PLLs.Aerospace Engineering and Engineering Mechanic
Employing dynamic fuzzy membership functions to assess environmental performance in the supplier selection process
The proposed system illustrates that logic fuzzy can be used to aid management in assessing a supplier's environmental performance in the supplier selection process. A user-centred hierarchical system employing scalable fuzzy membership functions implement human priorities in the supplier selection process, with particular focus on a supplier's environmental performance. Traditionally, when evaluating supplier performance, companies have considered criteria such as price, quality, flexibility, etc. These criteria are of varying importance to individual companies pertaining to their own specific objectives. However, with environmental pressures increasing, many companies have begun to give more attention to environmental issues and, in particular, to their suppliersâ environmental performance. The framework presented here was developed to introduce efficiently environmental criteria into the existing supplier selection process and to reflect on its relevant importance to individual companies. The system presented attempts to simulate the human preference given to particular supplier selection criteria with particular focus on environmental issues when considering supplier selection. The system considers environmental data from multiple aspects of a suppliers business, and based on the relevant impact this will have on a Buying Organization, a decision is reached on the suitability of the supplier. This enables a particular supplier's strengths and weaknesses to be considered as well as considering their significance and relevance to the Buying OrganizationPeer reviewe
Unveiling Sources of Heating in the Vicinity of the Orion BN/KL Hot Core as Traced by Highly Excited Inversion Transitions of Ammonia
Using the Expanded Very Large Array, we have mapped the vicinity of the Orion
BN/KL Hot Core with sub-arcsecond angular resolution in seven metastable
inversion transitions of ammonia: (J,K)=(6,6) to (12,12). This emission comes
from levels up to 1500 K above the ground state, enabling identification of
source(s) responsible for heating the region. We used this multi-transition
dataset to produce images of the rotational/kinetic temperature and the column
density of ammonia for ortho and para species separately and on a
position-by-position basis. We find rotational temperature and column density
in the range 160-490 K and (1-4)x10^17 cm^-2, respectively. Our
spatially-resolved images show that the highest (column) density and hottest
gas is found in a northeast-southwest elongated ridge to the southeast of
Source I. We have also measured the ortho-para ratio of ammonia, estimated to
vary in the range 0.9-1.6. Enhancement of ortho with respect to para and the
offset of hot ammonia emission peaks from known (proto)stellar sources provide
evidence that the ammonia molecules have been released from dust grains into
the gas-phase through the passage of shocks and not by stellar radiation. We
propose that the combined effect of Source I's proper motion and its
low-velocity outflow impinging on a pre-existing dense medium is responsible
for the excitation of ammonia and the Orion Hot Core. Finally, we found for the
first time evidence of a slow (5 km/s) and compact (1000 AU) outflow towards
IRc7.Comment: To appear in Astrophysical Journal Letters Special Issue on the EVLA.
8 pages, 4 figure
- âŠ