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The relationship between poverty and childhood well-being in Great Britain
Kangaroo disease
In March, 1954, a survey of part of the Murchison area was undertaken by Messrs Gooding and Harrison, Research Officers of the Agricultural Protection Board to investigate a reported outbreak of disease among kangaroos—predominantly Marloos, also known as Red or Plain Kangaroos (Macropus rufus)—which inhabit those areas. At the time the disease was not known by any special name so the name of Lumpy Jaw was officially adopted. Upon their return to Perth, these officers sent out a questionnaire to 67 pastoralists in the area, asking for information on the disease. Only 20 replies have been received but, from these, a lot of useful information has been obtained
On the tail of the dingo
A successful motorised expedition to collect information on the breeding areas and migratory movements of wild dogs was completed in March of this year. This was the second expedition of this nature organised by the Agriculture Protection Board and much valuable information was obtained which should simplify the work of the Board\u27s doggers in the guarding of the sheep-breeding areas
Computational Simulation and 3D Virtual Reality Engineering Tools for Dynamical Modeling and Imaging of Composite Nanomaterials
An adventure at engineering design and modeling is possible with a Virtual
Reality Environment (VRE) that uses multiple computer-generated media to let a
user experience situations that are temporally and spatially prohibiting. In
this paper, an approach to developing some advanced architecture and modeling
tools is presented to allow multiple frameworks work together while being
shielded from the application program. This architecture is being developed in
a framework of workbench interactive tools for next generation
nanoparticle-reinforced damping/dynamic systems. Through the use of system, an
engineer/programmer can respectively concentrate on tailoring an engineering
design concept of novel system and the application software design while using
existing databases/software outputs.Comment: Submitted on behalf of TIMA Editions
(http://irevues.inist.fr/tima-editions
Design, fabrication, and delivery of a charge injection device as a stellar tracking device
Six 128 x 128 CID imagers fabricated on bulk silicon and with thin polysilicon upper-level electrodes were tested in a star tracking mode. Noise and spectral response were measured as a function of temperature over the range of +25 C to -40 C. Noise at 0 C and below was less than 40 rms carriers/pixel for all devices at an effective noise bandwidth of 150 Hz. Quantum yield for all devices averaged 40% from 0.4 to 1.0 microns with no measurable temperature dependence. Extrapolating from these performance parameters to those of a large (400 x 400) array and accounting for design and processing improvements, indicates that the larger array would show a further improvement in noise performance -- on the order of 25 carriers. A preliminary evaluation of the projected performance of the 400 x 400 array and a representative set of star sensor requirements indicates that the CID has excellent potential as a stellar tracking device
Dynamics of Phononic Dissipation at the Atomic Scale: Dependence on Internal Degrees of Freedom
Dynamics of dissipation of a local phonon distribution to the substrate is a
key issue in friction between sliding surfaces as well as in boundary
lubrication. We consider a model system consisting of an excited nano-particle
which is weakly coupled with a substrate. Using three different methods we
solve the dynamics of energy dissipation for different types of coupling
between the nano-particle and the substrate, where different types of
dimensionality and phonon densities of states were also considered for the
substrate. In this paper, we present our analysis of transient properties of
energy dissipation via phonon discharge in the microscopic level towards the
substrate. Our theoretical analysis can be extended to treat realistic
lubricant molecules or asperities, and also substrates with more complex
densities of states. We found that the decay rate of the nano-particle phonons
increases as the square of the interaction constant in the harmonic
approximation.Comment: 10 pages, 6 figures, submitted to Phys. Rev.
Optical Conductivity in a Two-Band Superconductor: Pb
We demonstrate the effect of bandstructure on the superconducting properties
of Pb by calculating the strong-coupling features in the optical conductivity,
, due to the electron-phonon interaction. The importance of
momentum dependence in the calculation of the properties of superconductors has
previously been raised for MgB. Pb resembles MgB in that it is a two
band superconductor in which the bands' contributions to the Fermi surface have
very different topologies. We calculate by calculating a
memory function which has been recently used to analyze of
BiSrCaCuO. In our calculations the two components of
the Fermi surface are described by parameterizations of de Haas--van Alphen
data. We use a phonon spectrum which is a fit to neutron scattering data. By
including the momentum dependence of the Fermi surface good agreement is found
with the experimentally determined strong-coupling features which can be
described by a broad peak at around 4.5 meV and a narrower higher peak around 8
meV of equal height. The calculated features are found to be dominated by
scattering between states within the third band. By contrast scattering between
states in the second band leads to strong-coupling features in which the height
of the high energy peak is reduced by compared to that of the low
energy peak. This result is similar to that in the conventional isotropic
(momentum independent) treatment of superconductivity. Our results show that it
is important to use realistic models of the bandstructure and phonons, and to
avoid using momentum averaged quantities, in calculations in order to get
quantitatively accurate results
Evaluation of Vehicle Ride Height Adjustments Using a Driving Simulator
Testing of vehicle design properties by car manufacturers is primarily performed on-road and is resource-intensive, involving costly physical prototypes and large time durations between evaluations of alternative designs. In this paper, the applicability of driving simulators for the virtual assessment of ride, steering and handling qualities was studied by manipulating vehicle air suspension ride height (RH) (ground clearance) and simulator motion platform (MP) workspace size. The evaluation was carried out on a high-friction normal road, routinely used for testing vehicle prototypes, modelled in a driving simulator, and using professional drivers. The results showed the differences between the RHs were subjectively distinguishable by the drivers in many of the vehicle attributes. Drivers found standard and low RHs more appropriate for the vehicle in terms of the steering and handling qualities, where their performance was deteriorated, such that the steering control effort was the highest in low RH. This indicated inconsistency between subjective preferences and objective performance and the need for alternative performance metrics to be defined for expert drivers. Moreover, an improvement in drivers’ performance was observed, with a reduction of steering control effort, in larger MP configurations
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