53 research outputs found

    The effects of oblique waves and currents on the loadings and performance of tidal turbines

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    Tidal energy exploitation is at an early deployment stage and costs need to be reduced to improve the long term economic viability of the sector. High costs of tidal turbines are, in part, the result of load uncertainties, which lead to the use of high factors of safety in the design to ensure survival. One of the most important causes of uncertainty is hydrodynamic loadings. To date, most of the scaled model experiments with horizontal axis turbines investigating this issue have been carried out with collinear wave and current directions. To the authors’ knowledge, the work presented herein is the first experimental investigation of a horizontal axis turbine model subjected to combined oblique waves and current. Turbine performance and loading are measured for a 1:15 scale model tested in the FloWave circular, combined wave and current basin at the University of Edinburgh (UK). Three different flow directions were tested and each of them were also combined with regular waves in three different directions non-collinear with the flow. Fifteen physical quantities were measured including flow velocity, rotor and foundation loads and turbine speed. Characterisation of loads and turbine performance in those oblique current and wave conditions are presented. Waves affect means and standard deviation of rotor power and thrust, but off-axis waves are associated with lower thrust loads than head-on waves. Compared to current only, rotor torque and thrust standard deviations are higher in the presence of waves and almost twice as high when the wave crest is parallel to the rotor plan

    Fundamental issues in systems biology.

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    types: Journal Article; Research Support, Non-U.S. Gov'tIn the context of scientists' reflections on genomics, we examine some fundamental issues in the emerging postgenomic discipline of systems biology. Systems biology is best understood as consisting of two streams. One, which we shall call 'pragmatic systems biology', emphasises large-scale molecular interactions; the other, which we shall refer to as 'systems-theoretic biology', emphasises system principles. Both are committed to mathematical modelling, and both lack a clear account of what biological systems are. We discuss the underlying issues in identifying systems and how causality operates at different levels of organisation. We suggest that resolving such basic problems is a key task for successful systems biology, and that philosophers could contribute to its realisation. We conclude with an argument for more sociologically informed collaboration between scientists and philosophers.Funding received from the Economic and Social Research Council (ESRC), UK, and Overseas Conference Funding from the British Academy

    Integrating Human Health into Environmental Impact Assessment: An Unrealized Opportunity for Environmental Health and Justice

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    The National Environmental Policy Act and related state laws require many public agencies to analyze and disclose potentially significant environmental effects of agency actions, including effects on human health. In this paper we review the purpose and procedures of environmental impact assessment (EIA), existing regulatory requirements for health effects analysis, and potential barriers to and opportunities for improving integration of human health concerns within the EIA process. We use statutes, regulations, guidelines, court opinions, and empirical research on EIA along with recent case examples of integrated health impact assessment (HIA)/EIA at both the state and federal level. We extract lessons and recommendations for integrated HIA/EIA practice from both existing practices as well as case studies. The case studies demonstrate the adequacy, scope, and power of existing statutory requirements for health analysis within EIA. The following support the success of integrated HIA/EIA: a proponent recognizing EIA as an available regulatory strategy for public health; the openness of the agency conducting the EIA; involvement of public health institutions; and complementary objectives among community stakeholders and health practitioners. We recommend greater collaboration among institutions responsible for EIA, public health institutions, and affected stakeholders along with guidance, resources, and training for integrated HIA/EIA practice

    The state of the art in monitoring and verification—Ten years on

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    Resource mapping of agricultural wastes and residues Part 1: England and Wales

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    SIGLEAvailable from British Library Lending Division - LD:3816.465(ETSU-B--1055A) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

    Resource mapping of agricultural wastes and residues Appendices

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    Available from British Library Lending Division - LD:3816.465(ETSU-B--1055E) / BLDSC - British Library Document Supply CentreSIGLEGBUnited Kingdo

    Resource mapping of agricultural wastes and residues Annex to part 1: regional tables of results and maps of residue and waste distribution in England and Wales (continued)

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    SIGLEAvailable from British Library Lending Division - LD:3816.465(ETSU-B--1055C) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

    Resource mapping of agricultural wastes and residues Part 2: Scotland and Northern Ireland

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    SIGLEAvailable from British Library Lending Division - LD:3816.465(ETSU-B--1055D) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

    Environmental parameters on the United Kingdom continental shelf

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    20.00; incl. 8 mapsSIGLEAvailable from British Library Lending Division - LD:6244.38(OTH--84-201) / BLDSC - British Library Document Supply CentreGBUnited Kingdo

    Risk analysis of mooring failure Phase 1; bench-marking study

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    SIGLEAvailable from British Library Document Supply Centre- DSC:6244.2239(OTO--90-017) / BLDSC - British Library Document Supply CentreGBUnited Kingdo
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