Illustrative components of the geological environment

In this chapter we provide an account of the contribution made by the Geosphere, in particular bedrock geological materials (part of the lithosphere), groundwater and hydrochemistry to the development of a GDF. In order to put this in context we provide a brief account of the general requirements of these attributes, particularly in respect of the post closure safety and, to a lesser extent, the construction phase of the GDF. We also provide a brief summary of the international approach to using bedrock geological materials and go on to describe the summary properties from a range of bedrock geological materials (lithologies and formations) in England, Wales and Northern Ireland, illustrated from well-documented examples

AIR multigrid with GMRES polynomials (AIRG) and additive preconditioners for Boltzmann transport

We develop a reduction multigrid based on approximate ideal restriction (AIR) for use with asymmetric linear systems. We use fixed-order GMRES polynomials to approximate $A_\textrm{ff}^{-1}$ and we use these polynomials to build grid transfer operators and perform F-point smoothing. We can also apply a fixed sparsity to these polynomials to prevent fill-in. When applied in the streaming limit of the Boltzmann Transport Equation (BTE), with a P$^0$ angular discretisation and a low-memory spatial discretisation on unstructured grids, this "AIRG" multigrid used as a preconditioner to an outer GMRES iteration outperforms the lAIR implementation in hypre, with two to three times less work. AIRG is very close to scalable; we find either fixed work in the solve with slight growth in the setup, or slight growth in the solve with fixed work in the setup when using fixed sparsity. Using fixed sparsity we see less than 20% growth in the work of the solve with either 6 levels of spatial refinement or 3 levels of angular refinement. In problems with scattering AIRG performs as well as lAIR, but using the full matrix with scattering is not scalable. We then present an iterative method designed for use with scattering which uses the additive combination of two fixed-sparsity preconditioners applied to the angular flux; a single AIRG V-cycle on the streaming/removal operator and a DSA method with a CG FEM. We find with space or angle refinement our iterative method is very close to scalable with fixed memory use

Implications of the Patient Protection and Affordable Care Act for Health Inequities

To assess implications , opportunities, and challenges of health care reform for improving the health and health care of racially and ethnically diverse populations

Application of a diode array spectroradiometer to measuring the spectral scattering properties of cloud types in a laboratory

International audienceIn the last few years diode array spectroradiometers have become useful complements to traditional scanning instruments when measuring visible and ultraviolet solar radiation incident on the ground. This study describes the application of such an instrument to the problem of measuring the radiation scattered by different cloud-types in a laboratory environment. Details of how the instrument is incorporated into the experimental set-up are given together with the development of the system as a whole. The capability to measure a full spectrum for each scattering angle is an undoubted advantage, although the limited sensitivity impacts on the usefulness for optically thin clouds. Nevertheless example results are presented: (1) scattering phase functions at a range of wavelengths recorded simultaneously for water clouds, showing spectral deviation at the rainbow angle and verification of Mie theory; (2) likewise for mixed phase clouds, with evidence of both halo and rainbow features in a single scattering function; and, (3) detail of the forward scattering region in a glaciated cloud showing a barely perceptible halo feature, with implications for the small-scale structure of the ice crystals produced

AAO Starbugs: software control and associated algorithms

The Australian Astronomical Observatory's TAIPAN instrument deploys 150 Starbug robots to position optical fibres to accuracies of 0.3 arcsec, on a 32 cm glass field plate on the focal plane of the 1.2 m UK-Schmidt telescope. This paper describes the software system developed to control and monitor the Starbugs, with particular emphasis on the automated path-finding algorithms, and the metrology software which keeps track of the position and motion of individual Starbugs as they independently move in a crowded field. The software employs a tiered approach to find a collision-free path for every Starbug, from its current position to its target location. This consists of three path-finding stages of increasing complexity and computational cost. For each Starbug a path is attempted using a simple method. If unsuccessful, subsequently more complex (and expensive) methods are tried until a valid path is found or the target is flagged as unreachable.Comment: 10 pages, to be published in Proc. SPIE 9913, Software and Cyberinfrastructure for Astronomy IV; 201

Age and quality stratification of groundwater in the Triassic Sherwood Sandstone aquifer of South Yorkshire and the East Midlands, UK

Groundwater from the Triassic Sherwood Sandstone aquifer of the English East Midlands shows a well-documented evolution in chemistry and residence time as it flows downgradient from shallow unconfined conditions to greater depths, confined by Mercia Mudstone. The flow path covers a lateral distance of some 40 km and depths approaching 800 m. The presence of fresh groundwater (Cl = 15 mg/L, Na = 17 mg/L, SO4 = 144 mg/L, TDS = 500 mg/L) of likely Pleistocene age can be demonstrated down to about 500 m depth in the aquifer, some 10 km downgradient of its confined/unconfined interface. This is amongst the deepest fresh groundwater identified in the UK. Beyond that zone, salinity increases in response to dissolution of gypsum or anhydrite, giving Ca-SO4 groundwater. Further downgradient still, saline groundwater (TDS = 10 g/L) is encountered in the deepest part of the confined aquifer. Downgradient geochemical evolution and increasing residence time are also observed in the South Yorkshire section of the aquifer, to the north of the East Midlands flow path. Here, analogous sequential geochemical changes are observed, controlled by carbonate and sulphate mineral reactions, redox changes and silicate hydrolysis, with evidence of increased inputs of e.g. Na, Cl and SO4 from modern pollution at shallow depths in the unconfined aquifer. Redox conditions are more variable in the western part of the South Yorkshire aquifer, due to local confinement or semi-confinement by fine-grained Quaternary deposits overlying the Sherwood Sandstone. Ratios of δ13C in this section of aquifer increase from −14‰ at outcrop to −11‰ in Mercia-Mudstone-confined conditions as a result of gradual equilibration with aquifer carbonate under closed-system conditions. Ratios of δ18O and δ2H become more depleted, reaching −9‰ and −61‰ respectively, suggesting recharge under climatic conditions significantly cooler than the modern era. Increasing residence time is also indicated by increasing concentrations of a number of trace elements (e.g. Li, Rb, Sr, Mo). These transitions are also observed vertically within investigated boreholes in unconfined and semi-confined sections of the aquifer. Deep groundwater (160–170 m depth) from a borehole within the unconfined aquifer of South Yorkshire has δ18O and δ2H ratios as depleted as −9.2‰ and −67‰ respectively. Such depth stratification indicates that good-quality palaeowater, likely of Pleistocene age, can exist at depth even in the unconfined Sherwood Sandstone aquifer, and that vertical hydraulic conductivity is much lower than lateral. A paucity of boreholes in the Mercia-Mudstone-confined section of the South Yorkshire aquifer makes estimation of the lateral extent of fresh groundwater there more problematic, though brackish groundwater (Cl = 1300 mg/L, TDS = 5.5 g/L) has been identified 12 km east of the aquifer's confined margin

Sustainable farming with native rocks: the transition without revolution.

The development process which humanity passed through favored a series of conquests, reflected in the better quality of life and longevity, however, it also provoked upsets and severe transformation in the environment and in the human food security. Such process is driving the ecosystems to be homogeneous, and, therefore,the nutrients� supply, via nourishment. To change this panorama, the present work discusses the gains of incorporating the stonemeal technique as a strategic alternative to give back the essential fertile characteristics to the soils. This technology has the function of facilitating the rejuvenation of the soils and increasing the availability of the necessary nutrients to the full development of the plants which is a basic input for the proliferation of life in all its dimensions