1,049 research outputs found

    Just Following Instructions? The representation of parents in care proceedings

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    Pathways from pilot to demonstration : how can research advance CO2 geological storage deployment?

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    An international workshop was hosted by the British Geological Survey (BGS), supported by the United Kingdom’s Foreign and Commonwealth Office (FCO), from the 1st to the 3rd of March 2016 at the BGS offices in Keyworth, Nottingham, United Kingdom. The workshop objectives were to: Examine how pilot, field laboratory and laboratory projects can inform and advance large-scale CO2 storage and low-carbon geo-energy resources. Reinforce the importance of advancing CCS through practical experience at varied relevant scales: pilots/field labs (testing concepts) and demonstrations (deploy technologies and identify new technical questions for pilots to examine) Strengthening international links between field lab, pilot, demonstration and large scale project operators to make it easier to share lessons learned Exchange research learning between CCS and other geo-energy disciplines The workshop outcomes were intended to identify of opportunities for collaboration and development of outline proposals to advance CCS and geo-energy research through practical experience and demonstrations. Workshop invitees included policy makers, demonstration project representatives, academics and pilot project operators. A total of 75 delegates attended, who represented 46 organisations including research institutions, industry (national, multinational and suppliers), global and national CCS networks and trade associations (see attached delegate list – Appendix 1), and a government representative from UK DECC. Delegates were from 13 countries worldwide

    An experimental and analogue study of iron release from red sandstones

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    The Jurassic Entrada sandstone at Salt Wash Graben, Utah, USA, a red sandstone contains significant rock bleaching. The cause of the bleaching has been thought to be associated with the modern day CO2-rich fluids in the area which present on the surface by utalising the local fractures, some of which are filled with calcite and iron rich minerals (e.g. Jarosite). An experimental study was conducted to determine the cause of the bleaching. CO2 was found not to cause sandstone bleaching. However, the CO2 was found to mobilize significant amounts of iron from the fracture minerals suggesting that this is a possible source of the iron in the modern pore fluids

    Evaluation of barriers to national CO2 geological storage assessments

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    A survey to evaluate the main perceived barriers to national CO2 storage assessments was carried out in 2015, targeting countries where some Carbon dioxide Capture and Storage (CCS) activity was known or where CCS could potentially be implemented in the future. All the questionnaire respondents indicated that some level of national assessment had been achieved. In most cases, these assessments had been sufficient to allow policy makers to make informed decisions about priorities for follow-up actions. Where national storage assessments had been carried out, the major barriers had been mainly overcome through strong political and regulatory support for CCS and policies enabling access to relevant data

    Towards low-cost microchannel heat exchangers: vehicle heat recovery ventilator prototype

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    Paper presented to the 10th International Conference on Heat Transfer, Fluid Mechanics and Thermodynamics, Florida, 14-16 July 2014.Vehicles could save ~110 million gallons of gasoline per year in the U.S. with heat exchangers acting as heat recovery ventilators in the air conditioning systems. Even more energy could be saved with in-vehicle heat exchangers by reducing heating energy in plug-in vehicles. Currently, vehicles do not have heat recovery ventilators because of the high cost of conventional metal heat exchangers. To overcome this challenge, low-cost expanded polymer microchannel heat exchangers were studied. Forward conduction laser welding was used to join 25-micron thick linear low-density polyethylene sheets, which were then fixed into shape and expanded. The microchannel polymer heat exchangers were tested at various air flow rates. At the maximum flow rate, the effectiveness was ~70% and the implications of this expanded heat exchanger in other applications are discussed.cf201

    Stochastic processes and conformal invariance

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    We discuss a one-dimensional model of a fluctuating interface with a dynamic exponent z=1z=1. The events that occur are adsorption, which is local, and desorption which is non-local and may take place over regions of the order of the system size. In the thermodynamic limit, the time dependence of the system is given by characters of the c=0c=0 conformal field theory of percolation. This implies in a rigorous way a connection between CFT and stochastic processes. The finite-size scaling behavior of the average height, interface width and other observables are obtained. The avalanches produced during desorption are analyzed and we show that the probability distribution of the avalanche sizes obeys finite-size scaling with new critical exponents.Comment: 4 pages, 6 figures, revtex4. v2: change of title and minor correction

    The Effect of Hybrid Photovoltaic Thermal Device Operating Conditions on Intrinsic Layer Thickness Optimization of Hydrogenated Amorphous Silicon Solar Cells

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    Historically, the design of hybrid solar photovoltaic thermal (PVT) systems has focused on cooling crystalline silicon (c-Si)-based photovoltaic (PV) devices to avoid temperature-related losses. This approach neglects the associated performance losses in the thermal system and leads to a decrease in the overall exergy of the system. Consequently, this paper explores the use of hydrogenated amorphous silicon (a-Si:H) as an absorber material for PVT in an effort to maintain higher and more favourable operating temperatures for the thermal system. Amorphous silicon not only has a smaller temperature coefficient than c-Si, but also can display improved PV performance over extended periods of higher temperatures by annealing out defect states from the Staebler-Wronski effect. In order to determine the potential improvements in a-Si:H PV performance associated with increased thicknesses of the i-layers made possible by higher operating temperatures, a-Si:H PV cells were tested under 1 sun illumination (AM1.5) at temperatures of 25oC (STC), 50oC (representative PV operating conditions), and 90 oC (representative PVT operating conditions). PV cells with an i-layer thicknesses of 420, 630 and 840 nm were evaluated at each temperature. Results show that operating a-Si:H-based PV at 90 oC, with thicker i-layers than the cells currently used in commercial production, provided a greater power output compared to the thinner cells operating at either PV or PVT operating temperatures. These results indicate that incorporating a-Si:H as the absorber material in a PVT system can improve the thermal performance, while simultaneously improving the electrical performance of a-Si:H-based PV

    A semantical approach to equilibria and rationality

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    Game theoretic equilibria are mathematical expressions of rationality. Rational agents are used to model not only humans and their software representatives, but also organisms, populations, species and genes, interacting with each other and with the environment. Rational behaviors are achieved not only through conscious reasoning, but also through spontaneous stabilization at equilibrium points. Formal theories of rationality are usually guided by informal intuitions, which are acquired by observing some concrete economic, biological, or network processes. Treating such processes as instances of computation, we reconstruct and refine some basic notions of equilibrium and rationality from the some basic structures of computation. It is, of course, well known that equilibria arise as fixed points; the point is that semantics of computation of fixed points seems to be providing novel methods, algebraic and coalgebraic, for reasoning about them.Comment: 18 pages; Proceedings of CALCO 200

    Systematic review of economic evaluations and cost analyses of guideline implementation strategies

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    Objectives To appraise the quality of economic studies undertaken as part of evaluations of guideline implementation strategies; determine their resources use; and recommend methods to improve future studies. Methods Systematic review of economic studies undertaken alongside robust study designs of clinical guideline implementation strategies published (1966-1998). Studies assessed against the BMJ economic evaluations guidelines for each stage of the guideline process (guideline development, implementation and treatment). Results 235 studies were identified, 63 reported some information on cost. Only 3 studies provided evidence that their guideline was effective and efficient. 38 reported the treatment costs only, 12 implementation and treatment costs, 11 implementation costs alone, and two guideline development, implementation and treatment costs. No study gave reasonably complete information on costs. Conclusions Very few satisfactory economic evaluations of guideline implementation strategies have been performed. Current evaluations have numerous methodological defects and rarely consider all relevant costs and benefits. Future evaluations should focus on evaluating the implementation of evidence based guidelines. Keywords: Cost-effectiveness analysis, physician (or health care professional) behaviour, practice guidelines, quality improvement, systematic review.Peer reviewedAuthor versio
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