65,238 research outputs found

    Promoting green issues and sustainability in UK higher education libraries

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    Climate change affects us all. Individually and collectively, we must reduce our carbon footprint to protect the future of the planet. But how can higher education libraries contribute? In April of 2007, a request was made to SCONUL libraries – via LIS-SCONUL – for information on library green initiatives that they were taking forward. The responses highlighted that there is growing interest in the issue and that sustainability issues are beginning to be taken very seriously. This is partially driven by the greater awareness of the need to reduce carbon emissions throughout society. Specifically within higher education, it is also a result of encouragement by funding bodies, such as the Higher Education Funding Council for England (HEFCE) (see http://www.hefce. ac.uk/lgm/sustain/), through pressure from groups such as People and Planet and their ‘green league’ of higher education institutions (http:// peopleandplanet.org/gogreen/greenleague2007), and through rewards for excellence such as the Times Higher Education and Higher Education Academy Awards for an outstanding contribution by a higher education institution to sustainable development. Library staff are often active in wider institutional sustainability initiatives and can act as ‘champions’ for environmental issues and initiatives. Most of the libraries that responded to the request for information have aligned their green initiatives/ policies with those of their host organisation. Some libraries have participated in a wider institutional initiative to apply for the environmental management standard, ISO 14001. However, there are many specific ways that libraries can become more environmentally friendly and can make a difference

    Stability of large horizontal-axis axisymmetric wind turbines

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    The stability of large horizontal axis, axi-symmetric, power producing wind turbines was examined. The analytical model used included the dynamic coupling of the rotor, tower and power generating system. The aerodynamic loading was derived from blade element theory. Each rotor blade was permitted tow principal elastic bending degrees of freedom, one degree of freedom in torsion and controlled pitch as a rigid body. The rotor hub was mounted in a rigid nacelle which may yaw freely or in a controlled manner. The tower can bend in two principal directions and may twist. Also, the rotor speed can vary and may induce perturbation reactions within the power generating equipment. Stability was determined by the eigenvalues of a set of linearized constant coefficient differential equations. All results presented are based on a 3 bladed, 300 ft. diameter, 2.5 megawatt wind turbine. Some of the parameters varied were; wind speed, rotor speed structural stiffness and damping, the effective stiffness and damping of the power generating system and the principal bending directions of the rotor blades. Unstable or weakly stable behavior can be caused by aerodynamic forces due to motion of the rotor blades and tower in the plane of rotation or by mechanical coupling between the rotor system and the tower

    Causal Baryon Diffusion and Colored Noise

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    We construct a model of baryon diffusion which has the desired properties of causality and analyticity. The model also has the desired property of colored noise, meaning that the noise correlation function is not a Dirac delta function in space and time; rather, it depends on multiple time and length constants. The model can readily be incorporated in 3+1 dimensional second order viscous hydro-dynamical models of heavy ion collisions, which is particularly important at beam energies where the baryon density is large.Comment: 20 pages, 5 figure

    Neutrino nuclear response and photo nuclear reaction

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    Photo nuclear reactions are shown to be used for studying neutrino/weak nuclear responses involved in astro-neutrino nuclear interactions and double beta decays. Charged current weak responses for ground and excited states are studied by using photo nuclear reactions through isobaric analog states of those states, while neutral current weak responses for excited states are studied by using photo nuclear reactions through the excited states. The weak interaction strengths are studied by measuring the cross sections of the photo nuclear reactions, and the spin and parity of the state are studied by measuring angular correlations of particles emitted from the photo nuclear reactions. Medium-energy polarized photons obtained from laser photons scattered off GeV electrons are very useful. Nuclear responses studied by photo nuclear reactions are used to evaluate neutrino/weak nuclear responses, i.e. nuclear beta and double beta matrix elements and neutrino nuclear interactions, and to verify theoretical calculations for them.Comment: 8 pages, 6 figure

    Robustness of d-Density Wave Order to Nonmagnetic Impurities

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    Effect of finite density of nonmagnetic impurities on a coexisting phase of d-density wave (DDW) order and d-wave superconducting (DSC) order is studied using Bogoliubov-de Gennes (BdG) method. The spatial variation of the inhomogeneous DDW order due to impurities has a strong correlation with that of density, which is very different from that of DSC order. The length scale associated with DDW is found to be of the order of a lattice spacing. The nontrivial inhomogeneities are shown to make DDW order much more robust to the impurities, while DSC order becomes very sensitive to them. The effect of disorder on the density of states is also discussed.Comment: 4 pages, 3 PostScript figure
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