16,994 research outputs found

    Education and Skill Development through the Reconfiguration of Discarded Hardware: Turning Base Metal into intellectual Capital

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    This paper examines an intervention in Europe which enables untypical individuals to acquire skills and competences in order to enter IT related employment. To do this they need to acquire a threshold level of intellectual capital so that they are considered sufficiently competent to gain employment. This can therefore provide the industry with a solid foundation of the necessary support staff, capable of providing services to the local community supporting such educational initiatives. This initiative can then release the more conventionally educated to work at the cutting edge of industry. As a driver for wealth generation in India, the IT industry is remarkable. It demands a wide spectrum of intellectual capital. As diffusion of IT technology is predicted to pervade throughout the subcontinent, the demand for all levels of competence would seem to be buoyant. The training environment covered in this case study complements the traditional educational system and could furnish alternative career opportunities to certain sections of the community. This paper takes a strategic view throughout. The fallacy of composition has to be taken seriously. What is true for a part is not true of the whole. To place this in the context of this paper; whilst a workshop to help unemployed people build computers in Sheffield may work, it is not necessarily appropriate to draw the conclusions that it will be effective when implemented over the whole of the Indian Subcontinent

    Evaluation of shear mounted elastomeric damper

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    Viton-70 elastomeric shear mounted damper was built and tested on a T-55 power turbine spool in the rotor's high speed balancing rig. This application of a shear mounted elastomeric damper demonstrated for the first time, the feasibility of using elastomers as the primary rotor damping source in production turbine engine hardware. The shear damper design was selected because it was compatible with actual gas turbine engine radial space constraints, could accommodate both the radial and axial thrust loads present in gas turbine engines, and was capable of controlled axial preload. The shear damper was interchangeable with the production T-55 power turbine roller bearing support so that a direct comparison between the shear damper and the production support structure could be made. Test results show that the Viton-70 elastomer damper operated successfully and provided excellent control of both synchronous and nonsynchronous vibrations through all phases of testing up to the maximum rotor speed of 16,000 rpm. Excellent correlation between the predicted and experienced critical speeds, mode shapes and log decrements for the power turbine rotor and elastomer damper assembly was also achieved

    Parallizable manifolds and the fundamental group

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    ntroduction. Low-dimensional topology is dominated by the fundamental group. However, since every finitely presented group is the fundamental group of some closed 4-manifold, it is often stated that the effective influence of π1 ends in dimension three. This is not quite true, however, and there are some interesting border disputes. In this paper, we show that, by imposing the extra condition of parallelizability on the tangent bundle, the dominion of π1 is extended by an extra dimension

    Introduction: Religious plurality, interreligious pluralism, and spatialities of religious difference

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    The introduction to this special section foregrounds the key distinction between ‘religious plurality’ and ‘interreligious pluralism’. Building from the example of a recent controversy over an exhibition on shared religious sites in Thessaloniki, Greece, we analyze the ways in which advocates and adversaries of pluralism alternately place minority religions at the center or attempt to relegate them to the margins of visual, spatial, and political fields. To establish the conceptual scaffolding that supports this special section, we engage the complex relations that govern the operations of state and civil society, sacrality and secularity, as well as spectacular acts of disavowal that simultaneously coincide with everyday multiplicities in the shared use of space. We conclude with brief summaries of the four articles that site religious plurality and interreligious pluralism in the diverse contexts of Brazil, Russia, Sri Lanka, and the Balkans

    An Intrinsic Approach to Forces in Magnetoelectric Media

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    This paper offers a conceptually straightforward method for the calculation of stresses in polarisable media based on the notion of a drive form and its property of being closed in spacetimes with symmetry. After an outline of the notation required to exploit the powerful exterior calculus of differential forms, a discussion of the relation between Killing isometries and conservation laws for smooth and distributional drive forms is given. Instantaneous forces on isolated spacetime domains and regions with interfaces are defined, based on manifestly covariant equations of motion. The remaining sections apply these notions to media that sustain electromagnetic stresses, with emphasis on homogeneous magnetoelectric material. An explicit calculation of the average pressure exerted by a monochromatic wave normally incident on a homogeneous, magnetoelectric slab in vacuo is presented and the concluding section summarizes how this pressure depends on the parameters in the magnetoelectric tensors for the medium.Comment: 25 pages, 3 figures, to appear in Il Nuovo Cimento B, proceedings of GCM8, Catania (Oct 2008) - References added, minor corrections mad

    The foaming of lavas

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    Foaming is of great practical and theoretical significance for volcanic processes on the earth, the moon, and perhaps the meteorite parent bodies. The theory of foams agrees with steelmaking experience to indicate that their presence depends on the existence of solutes in the lavas which reduce the surface tension, and are not saturated. These solutes concentrate at the surface, and are called surfactants. The surfactant responsible for the formation of volcanic ash was not identified; it appears to be related to the oxygen partial pressure above the lava. This fact may explain why lunar and meteoritic melts are not observed to foam. Experimental studies are needed to clarify the process

    High Speed Balancing Applied to the T700 Engine

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    The work performed under Contracts NAS3-23929 and NAS3-24633 is presented. MTI evaluated the feasibility of high-speed balancing for both the T700 power turbine rotor and the compressor rotor. Modifications were designed for the existing Corpus Christi Army Depot (CCAD) T53/T55 high-speed balancing system for balancing T700 power turbine rotors. Tests conducted under these contracts included a high-speed balancing evaluation for T700 power turbines in the Army/NASA drivetrain facility at MTI. The high-speed balancing tests demonstrated the reduction of vibration amplitudes at operating speed for both low-speed balanced and non-low-speed balanced T700 power turbines. In addition, vibration data from acceptance tests of T53, T55, and T700 engines were analyzed and a vibration diagnostic procedure developed

    An imaging and spectroscopic study of the planetary nebulae in NGC 5128 (Centaurus A): Planetary nebulae catalogues

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    Imaging and spectroscopic observations of planetary nebulae (PNe) in the nearest large elliptical galaxy NGC 5128 (Centaurus A), were obtained to find more PNe and measure their radial velocities. NTT imaging was obtained in 15 fields in NGC 5128 over an area of about 1 square degree with EMMI using [O III] and off-band filters. Newly detected sources, combined with literature PNe, were used as input for VLT FLAMES multi-fibre spectroscopy in MEDUSA mode. Spectra of the 4600-5100A region were analysed and velocities measured based on emission lines of [O III]4959,5007A and often H-beta. The chief results are catalogues of 1118 PN candidates and 1267 spectroscopically confirmed PNe in NGC 5128. The catalogue of PN candidates contains 1060 PNe discovered with EMMI imaging and 58 from literature surveys. The spectroscopic PN catalogue has FLAMES radial velocity and emission line measurements for 1135 PNe, of which 486 are new. Another 132 PN radial velocities are available from the literature. For 629 PNe observed with FLAMES, H-beta was measured in addition to [O III]. Nine targets show double-lined or more complex profiles, and their possible origin is discussed. FLAMES spectra of 48 globular clusters were also targetted: 11 had emission lines detected (two with multiple components), but only 3 are PNe likely to belong to the host globular. The total of 1267 confirmed PNe in NGC 5128 with radial velocity measurements (1135 with small velocity errors) is the largest collection of individual kinematic probes in an early-type galaxy. This PN dataset, as well as the catalogue of PN candidates, are valuable resources for detailed investigation of the stellar population of NGC 5128. [Abridged]Comment: 19 pages, 11 figures. Accepted for publication in Astronomy and Astrophysics. Tables 7 - 11 available in electronic form at CDS. Replaced with a few typos fixe
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