33 resultados para Fishman, Steve


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Two evacuation trials were conducted within Brazilian library facilities by FSEG staff in January 2005. These trials represent one of the first such trials conducted in Brazil. The purpose of these evacuation trials was to collect pre-evacuation time data from a population with a cultural background different to that found in western Europe. In total some 34 pre-evacuation times were collected from the experiments and these ranged from 5 to 98 seconds with a mean pre-evacuation time of 46.7 seconds

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Bulk and interdendritic flow during solidification alters the microstructure development, potentially leading to the formation of defects. In this paper, a 3D numerical model is presented for the simulation of dendritic growth in the presence of fluid flow in both liquid and semi-solid zones during solidification. The dendritic growth was solved by the combination of a stochastic nucleation approach with a finite difference solution of the solute diffusion equation and. a projection method solution of the Navier-Stokes equations. The technique was applied first to simulate the growth of a single dendrite in 2D and 3D in an isothermal environment with forced fluid flow. Significant differences were found in the evolution of dendritic morphology when comparing the 2D and 3D results. In 3D the upstream arm has a faster growth velocity due to easier flow around the perpendicular arms. This also promotes secondary arm formation on the upstream arm. The effect of fluid flow on columnar dendritic growth and micro-segregation in constrained solidification conditions is then simulated. For constrained growth, 2D simulations lead to even greater inaccuracies as compared to 3D.

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Thermoelectric currents in the presence of a magnetic field generate Lorentz forces which can drive fluid flow. In the case of dendritic growth a naturally occurring thermoelectric current exists and in the presence of a high magnetic field micro convections are generated. Experimental evidence has attributed changes in microstructure to this effect. A numerical model has been developed to study the flow field around an unconstricted equiaxed dendrite growing under these conditions. The growth is modeled in 2D and 3D by an enthalpy based method and a complex flow structure has been predicted. Using a pseudo-3D approximation for economy, realistic 2D simulations are obtained where a fully coupled transient scheme reveals significant changes to the dendrite morphology reflecting experimental evidence. There is a rotation of the preferred direction of growth and increased secondary branching.

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The tilt-casting method is used to achieve tranquil filling of gamma-TiAl turbine blades. The reactive alloy is melted in a cold crucible using an induction coil and then the complete crucible-mould- running system assembly is rotated through 180degrees to transfer the metal into the mould. The induction current is ramped down gradually as the rotation starts and the mould is preheated to maintain superheat. The liquid metal then enters the mould and the gas within it (argon) escapes through the inlet aperture and through auxiliary vents. Solidification starts as soon the metal enters the mould and it is important to account for this effect to predict and prevent misruns. The rotation rate has to be controlled carefully to allow sufficient time for gas evacuation, but at the same time preserve superheat. This 3-phase system is modelled using the FV method, with a fast implicit numerical scheme used to capture the transient liquid free surface. The enthalpy method is used to model solidification and predict defects such as trapped bubbles, macro-porosity or surface connected porosity. Modeling is used to support an experimental program for the development of a production method for gamma-TiAl blades, with a target length of 40cm. The experiments provide validation for the model and the model in turn optimizes the tilt-casting process. The work is part of the EU project IMPRESS.

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This paper explores the extent to which film can be viewed as a discursive practice and as such the extent to which it can be seen as an element central to the essence of technology more universally defined. Our analysis of recurring visual and narrative motifs and metaphors around the representation of technology in specific films will consider how these representations are part of wider discursive practices around conceptualising technology.

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'To Tremble the Zero: Art in the Age of Algorithmic Reproduction' is a philosophic, political and sensuous journey playing with (and against) Benjamin's 'Art in the Age of Mechanical Reproduction'. In an age inundated by the 'post-': postmodernity, posthuman, post art, postsexual, post-feminist, post-society, post-nation, etc, 'To Tremble the Zero' sets out to re/present the nature of what it means to do or make 'art', as well as what it means to be or have 'human/ity' when the ground is nothing other than the fractal, and algorithmically infinite, combinations of zero and one. The work will address also the unfortunate way in which modern forms of metaphysics continue to creep 'unsuspectingly' into our understanding of contemporary media/electronic arts, despite (or perhaps even because of) the attempts by Latour, Badiou, or Agamben especially when addressing the zero/one as if a contradictory 'binary' rather than as a kind of 'slice' or (to use Deleuze and Guattari) an immanent plane of immanence. This work argues that by retrieving Benjamin, Einstein, Gödel, and Haraway, a rather different story of art can be told.

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In this book, expert energy economists assess the energy policy of thirty-one countries and the role of nuclear power. For many years the shock of Chernobyl took nuclear power off the agenda in most countries. Intense public relations activities by the industry, increasing evidence of climate change and failures to effectively reduce greenhouse gas emissions, have brought nuclear power issues back to the forefront of policy discussion in the nuclear renaissance countries. But some countries are just not prepared to go in that direction and, indeed, are still divesting themselves of their nuclear legacy, the nuclear phase-out countries. And how are nuclear issues being approached in the industrializing countries? An in-depth country-by-country analysis is presented within this framework. Out of such an analysis emerge thematic discussions on, among others, strategy in energy policy; nuclear plant safety, the impacts of nuclear accidents; the adequacy of nuclear power expertise. [Source: publisher's product description].

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In this book, the top specialists in each aspect of reward focus on the issues of the moment, they also identify the most significant areas of change incorporating the latest research and challenge conventional thinking, providing a truly critical perspective. An invaluable addition for both practitioners and sophisticated students.

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This is about politics and protest, or rather about a politics of protest, and of rebellion. But it is also about creativity and the way in which theory and practice combine within the context of the ‘productive/creative’ process. In this case the combination is explicit and can be traced along a clear trajectory. The following will set out the way in which the accompanying piece of music – a cover of the 1969 protest song Leaving on a Jet Plane by Peter, Paul & Mary - came into being. In doing so it will make reference to a number of theoretical ideas/concepts that fed into the productive process and/or appeared relevant postproduction. It will draw on various aspects of thought from Heidegger (Standing reserve, Enframing and Authenticity), Camus (The Rebel), Foucault (Luminosity), and Deleuze (Immanence, Difference and Repetition and The Fold). [From the Author].

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This guide has been written for support staff, working with people with learning disabilities, who are new to challenging behaviour or facing it for the first time. It is a self-help guide and provides practical and realistic information on how direct care staff can develop strageties to support people whose behaviour is challenging and develop their skills in this area.

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Pneumatic conveying of powder and granular material involve the mixed flow of solid particles in air. Characterisation of solid/gas flow regimes is important for the design, operation and control of plants involving such two-phase processes. This paper describes preliminary studies directed at identifying flow regimes in solid/gas flows by analysis of the process `noise' signals from a flow transmitter which has a relatively wide frequency response.

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Granular air-borne particles generally carry very small amounts of electric charge as a consequence of charging by the triboelectric effect. The presence of such particles induces charge of opposite polarity on a stationary conducting electrode. The amount of charge carried by the particles and the trajectories of the particles have significant random components and the signals produced are of very low level. The signal processing is further complicated by the random variation in the concentration of particles, i.e. the solid/gas ratio. This paper compares the results obtained from the electrostatic modelling of such sensors with those obtained from experiments.

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Rule testing in transport scheduling is a complex and potentially costly business problem. This paper proposes an automated method for the rule-based testing of business rules using the extensible Markup Language for rule representation and transportation. A compiled approach to rule execution is also proposed for performance-critical scheduling systems.

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Gas-solids two phase systems are widely employed within process plant in the form of pneumatic conveyors, dust extraction systems and solid fuel injection systems. The measurement of solids phase velocity therefore has wide potential application in flow monitoring and, in conjunction with density measurement instrumentation, solids mass flow rate measurement. Historically, a number of authors have detailed possible measurement techniques, and some have published limited test results. It is, however, apparent that none of these technologies have found wide application in industry. Solids phase velocity measurements were undertaken using real time cross correlation of signals from two electrostatic sensors spaced axially along a pipeline conveying pulverised coal (PF). Details of the measurement equipment, the pilot scale test rig and the test results are presented.