14,977 research outputs found
Digital exclusion: potential implications for social work education
QAA Subject Benchmark 5.9 requires social work students to demonstrate the ability to have a critical understanding of the social impact of ICT, including an awareness of the impact of the 'digital divide'. In the twenty-first century, the implications of digital exclusion may become increasingly relevant for the social work profession with its values of empowerment and anti-oppressive practices. As governments and organisations move closer to the provision of online services, the social worker may find themselves addressing the disempowerment of service users and carers disconnected from a virtual welfare state. The concern is that Benchmark 5.9 does not go far enough, that the full significance of this requirement may not be sufficiently realised and a greater awareness urgently called for
Dynamical Systems On Three Manifolds Part II: 3-Manifolds,Heegaard Splittings and Three-Dimensional Systems
The global behaviour of nonlinear systems is extremely important in control
and systems theory since the usual local theories will only give information
about a system in some neighbourhood of an operating point. Away from that
point, the system may have totally different behaviour and so the theory
developed for the local system will be useless for the global one.
In this paper we shall consider the analytical and topological structure of
systems on 2- and 3- manifolds and show that it is possible to obtain systems
with 'arbitrarily strange' behaviour, i.e., arbitrary numbers of chaotic
regimes which are knotted and linked in arbitrary ways. We shall do this by
considering Heegaard Splittings of these manifolds and the resulting systems
defined on the boundaries.Comment: 15 pages with 9 pictures. Accepted by Int. J. of Bifurcation and
Chao
Simultaneous ion sputter polishing and deposition
Results of experiments to study ion beam sputter polishing in conjunction with simultaneous deposition as a mean of polishing copper surfaces are presented. Two types of simultaneous ion sputter polishing and deposition were used in these experiments. The first type utilized sputter polishing simultaneous with vapor deposition, and the second type utilized sputter polishing simultaneous with sputter deposition. The etch and deposition rates of both techniques were studied, as well as the surface morphology and surface roughness
Apparatus for producing oxidation protection coatings for polymers
A polymeric substrate is coated with a metal oxide film to provide oxidation protection in low Earth orbital environments. The film contains about 4 volume percent polymer to provide flexibility. A coil of polymer materials moves through an ion beam as it is fed between reels. The ion beam first cleans the polymer material surface and then sputters the film material from a target onto this surface
Vertex Operators in 2K Dimensions
A formula is proposed which expresses free fermion fields in 2K dimensions in
terms of the Cartan currents of the free fermion current algebra. This leads,
in an obvious manner, to a vertex operator construction of nonabelian free
fermion current algebras in arbitrary even dimension. It is conjectured that
these ideas may generalize to a wide class of conformal field theories.Comment: Minor change in notation. Change in references
A Pyramid Scheme for Particle Physics
We introduce a new model, the Pyramid Scheme, of direct mediation of SUSY
breaking, which is compatible with the idea of Cosmological SUSY Breaking
(CSB). It uses the trinification scheme of grand unification and avoids
problems with Landau poles in standard model gauge couplings. It also avoids
problems, which have recently come to light, associated with rapid stellar
cooling due to emission of the pseudo Nambu-Goldstone Boson (PNGB) of
spontaneously broken hidden sector baryon number. With a certain pattern of
R-symmetry breaking masses, a pattern more or less required by CSB, the Pyramid
Scheme leads to a dark matter candidate that decays predominantly into leptons,
with cross sections compatible with a variety of recent observations. The dark
matter particle is not a thermal WIMP but a particle with new strong
interactions, produced in the late decay of some other scalar, perhaps the
superpartner of the QCD axion, with a reheat temperature in the TeV range. This
is compatible with a variety of scenarios for baryogenesis, including some
novel ones which exploit specific features of the Pyramid Scheme.Comment: JHEP Latex, 32 pages, 1 figur
Deposition of diamondlike carbon films
A diamondlike carbon film is deposited in the surface of a substrate by exposing the surface to an argon ion beam containing a hydrocarbon. The current density in the ion beam is low during initial deposition of the film. Subsequent to this initial low current condition, the ion beam is increased to full power. At the same time, a second argon ion beam is directed toward the surface of the substrate. The second ion beam has an energy level much greater than that of the ion beam containing the hydrocarbon. This addition of energy to the system increases mobility of the condensing atoms and serves to remove lesser bound atoms
Model validation for a noninvasive arterial stenosis detection problem
Copyright @ 2013 American Institute of Mathematical SciencesA current thrust in medical research is the development of a non-invasive method for detection, localization, and characterization of an arterial stenosis (a blockage or partial blockage in an artery). A method has been proposed to detect shear waves in the chest cavity which have been generated by disturbances in the blood flow resulting from a stenosis. In order to develop this methodology further, we use both one-dimensional pressure and shear wave experimental data from novel acoustic phantoms to validate corresponding viscoelastic mathematical models, which were developed in a concept paper [8] and refined herein. We estimate model parameters which give a good fit (in a sense to be precisely defined) to the experimental data, and use asymptotic error theory to provide confidence intervals for parameter estimates. Finally, since a robust error model is necessary for accurate parameter estimates and confidence analysis, we include a comparison of absolute and relative models for measurement error.The National Institute of Allergy and Infectious Diseases, the Air Force Office of Scientific Research, the Deopartment of Education and the Engineering and Physical Sciences Research Council (EPSRC)
Surface texturing of fluoropolymers
A method is disclosed for improving surface texture for adhesive bonding, metal bonding, substrate plating, decal substrate preparation, and biomedical implant applications. The surface to be bonded is dusted in a controlled fashion to produce a disbursed layer of fine mesh particles which serve as masks. The surface texture is produced by impinging gas ions on the masked surface. The textured surface takes the form of pillars or cones. The bonding material, such as a liquid epoxy, flows between the pillars which results in a bond having increased strength. For bonding metals a thin film of metal is vapor or sputter deposited onto the textured surface. Electroplating or electroless plating is then used to increase the metal thickness in the desired amount
Oxidation protection coatings for polymers
A polymeric substrate is coated with a metal oxide film to provide oxidation protection in low Earth orbital environments. The film contains about 4 volume percent polymer to provide flexibility. A coil of polymer material moves through an ion beam as it is fed between reels. The ion beam first cleans the polymer material surface and then sputters the film material from a target onto this surface
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