2,722 research outputs found
Aerodynamic investigations of ventilated brake discs.
The heat dissipation and performance of a ventilated brake disc strongly depends
on the aerodynamic characteristics of the flow through the rotor passages. The
aim of this investigation was to provide an improved understanding of ventilated
brake rotor flow phenomena, with a view to improving heat dissipation, as well
as providing a measurement data set for validation of computational fluid
dynamics methods. The flow fields at the exit of four different brake rotor
geometries, rotated in free air, were measured using a five-hole pressure probe
and a hot-wire anemometry system. The principal measurements were taken using
two-component hot-wire techniques and were used to determine mean and unsteady
flow characteristics at the exit of the brake rotors. Using phase-locked data
processing, it was possible to reveal the spatial and temporal flow variation
within individual rotor passages. The effects of disc geometry and rotational
speed on the mean flow, passage turbulence intensity, and mass flow were
determined. The rotor exit jet and wake flow were clearly observed as
characterized by the passage geometry as well as definite regions of high and
low turbulence. The aerodynamic flow characteristics were found to be reasonably
independent of rotational speed but highly dependent upon rotor geometry
Density-wave phases of dipolar fermions in a bilayer
We investigate the phase diagram of dipolar fermions with aligned dipole
moments in a two-dimensional (2D) bilayer. Using a version of the
Singwi-Tosi-Land-Sjolander scheme recently adapted to dipolar fermions in a
single layer [M. M. Parish and F. M. Marchetti, Phys. Rev. Lett. 108, 145304
(2012)], we determine the density-wave instabilities of the bilayer system
within linear response theory. We find that the bilayer geometry can stabilize
the collapse of the 2D dipolar Fermi gas with intralayer attraction to form a
new density wave phase that has an orientation perpendicular to the density
wave expected for strong intralayer repulsion. We thus obtain a quantum phase
transition between stripe phases that is driven by the interplay between strong
correlations and the architecture of the low dimensional system.Comment: 5 pages, 3 figure
Effect of students\u27 expectations
This research suggests that public disclosure of evaluations best be curtailed
Rapid construction of mycobacterial mutagenesis vectors using ligation-independent cloning
Targeted mutagenesis is one of the major tools for determining the function of a given gene and its involvement in bacterial pathogenesis. In mycobacteria, gene deletion is often accomplished by using allelic exchange techniques that commonly utilise a suicide delivery vector. We have adapted a widely-used suicide delivery vector (p1NIL) for cloning two flanking regions of a gene using ligation independent cloning (LIC). The pNILRB plasmid series produced allow a faster, more efficient and less laborious cloning procedure. In this paper we describe the making of pNILRB5, a modified version of p1NIL that contains two pairs of LIC sites flanking either a sacB or a lacZ gene. We demonstrate the success of this technique by generating 3 mycobacterial mutant strains. These vectors will contribute to more high-throughput methods of mutagenesis
Bound states in a quasi-two-dimensional Fermi gas
We consider the problem of N identical fermions of mass M and one
distinguishable particle of mass m interacting via short-range interactions in
a confined quasi-two-dimensional (quasi-2D) geometry. For N=2 and mass ratios
M/m<13.6, we find non-Efimov trimers that smoothly evolve from 2D to 3D. In the
limit of strong 2D confinement, we show that the energy of the N+1 system can
be approximated by an effective two-channel model. We use this approximation to
solve the 3+1 problem and we find that a bound tetramer can exist for mass
ratios M/m as low as 5 for strong confinement, thus providing the first example
of a universal, non-Efimov tetramer involving three identical fermions.Comment: 5 pages, 4 figure
Wheat quality surveys in Western Australia
SINCE 1956 a number of collaborative wheat quality surveys have been carried out in Western Australia by Co-operative Bulk Handling Co. Ltd. and the Department of Agriculture.
The work was undertaken to provide facts which may be used to determine the possible advantages to this State\u27s wheat industry of alterations in the receival and marketing arrangements.
The various surveys are described in this article
What Are We Goin\u27 To Do? : When There\u27s Nothing To Do On Sunday
https://digitalcommons.library.umaine.edu/mmb-vp/5602/thumbnail.jp
Grain moisture problems on the south coast
In most West Australian grain growing districts high temperatures and dry weather at grain maturation are ideal for harvesting and enable delivery of grain with acceptable moisture levels. Grain from W.A. is known in world markets as a good quality dry product which is unlikely to deteriorate in storage. However, growers in coastal areas and particularly those south of Narrogin sometimes have trouble harvesting grain below the receival limit of 12 per cent moisture
Grow barley for malt or feed
MALTING barley can be grown in certain areas receiving more than 13 inches annual rainfall, and farmers have to make a choice between growing barley for malt or feed in these areas
A Data Fusion Technique to Detect Wireless Network Virtual Jamming Attacks
The file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.Wireless communications are potentially exposed to jamming due to the openness of the medium and, in particular, to virtual jamming, which allows more energy-efficient attacks. In this paper we tackle the problem of virtual jamming attacks on IEEE 802.11 networks and present a data fusion solution for the detection of a type of virtual jamming attack (namely, NAV attacks), based on the real-time monitoring of a set of metrics. The detection performance is evaluated in a number of real scenarios
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