1,363 research outputs found

    Study of conceptual deep space monitor communications systems using a single earth satellite. Volume III - Appendix Final report

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    Condensed technical survey for deep space monitor communications system using earth satellit

    Practising innovation: the power of the artist

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    Superpressure balloon flights from Christchurch, New Zealand, July 1968 - December 1969

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    Strain gages on superpressure balloon flights from Christchurch, New Zealand - Jul. 1968 to Dec. 196

    Cultural planning and chaos theory in cyberspace: some notes on a digital cultural atlas project for Western Sydney

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    A perennial issue for digital politics has been the debate between those who claim a liberatory role for digital technologies and those who see them as instruments for a more effective oppression. We prefer to avoid such abstract oppositions and ask more specific questions: what kind of digital technology, used in what way by whom, for what purposes in what contexts, may support the efforts of those who work for a better, more open society? To focus our enquiry we look at the intersection of digital systems and planning. Planning in a general sense is a fundamental human activity in all societies exercising the rationality that has come to define humanity since the ancient Greeks. Yet the dominant form of planning in western societies today employs a specific form of `rationality which has emerged only recently, labelled `Occidental rationalism by Weber (1930:26), which insists on crisp, clear categories and a linear, reductive logic. Starting with Weber himself there has been a continuous tradition of critique of this form of reason, which we will categorize as linear reasoning

    A researcher's perspective on electronic scholarly communication

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    New information and communications technologies are transforming scholarly communication. Presents a humanities and social sciences researcher’s perspective on these changes. Argues that researchers and research intermediaries need to find new ways of working together in order to understand and take full advantage of the emerging forms and media for scholarly communication. Keywords: Electronic publishing, Communications, Researc

    Three-Axis Distributed Fiber Optic Strain Measurement in 3D Woven Composite Structures

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    Recent advancements in composite materials technologies have broken further from traditional designs and require advanced instrumentation and analysis capabilities. Success or failure is highly dependent on design analysis and manufacturing processes. By monitoring smart structures throughout manufacturing and service life, residual and operational stresses can be assessed and structural integrity maintained. Composite smart structures can be manufactured by integrating fiber optic sensors into existing composite materials processes such as ply layup, filament winding and three-dimensional weaving. In this work optical fiber was integrated into 3D woven composite parts at a commercial woven products manufacturing facility. The fiber was then used to monitor the structures during a VARTM manufacturing process, and subsequent static and dynamic testing. Low cost telecommunications-grade optical fiber acts as the sensor using a high resolution commercial Optical Frequency Domain Reflectometer (OFDR) system providing distributed strain measurement at spatial resolutions as low as 2mm. Strain measurements using the optical fiber sensors are correlated to resistive strain gage measurements during static structural loading. Keywords: fiber optic, distributed strain sensing, Rayleigh scatter, optical frequency domain reflectometr

    Functional map of arrestin binding to phosphorylated opsin, with and without agonist

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    Arrestins desensitize G protein-coupled receptors (GPCRs) and act as mediators of signalling. Here we investigated the interactions of arrestin-1 with two functionally distinct forms of the dim-light photoreceptor rhodopsin. Using unbiased scanning mutagenesis we probed the individual contribution of each arrestin residue to the interaction with the phosphorylated apo-receptor (Ops-P) and the agonist-bound form (Meta II-P). Disruption of the polar core or displacement of the C-tail strengthened binding to both receptor forms. In contrast, mutations of phosphate-binding residues (phosphosensors) suggest the phosphorylated receptor C-terminus binds arrestin differently for Meta II-P and Ops-P. Likewise, mutations within the inter-domain interface, variations in the receptor-binding loops and the C-edge of arrestin reveal different binding modes. In summary, our results indicate that arrestin-1 binding to Meta II-P and Ops-P is similarly dependent on arrestin activation, although the complexes formed with these two receptor forms are structurally distinct

    The impact of cattle access on ecological water quality in streams: Examples from agricultural catchments within Ireland

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    Unrestricted cattle access to rivers and streams represent a potentially significant localised pressure on freshwater systems. However there is no consensus in the literature on the occurrence and extent of impact and limited research has examined the effects on aquatic biota in the humid temperate environment examined in the present study. Furthermore, this is one of the first times that research consider the potential for cattle access impacts in streams of varying water quality in Northern Europe. We investigated the effects of cattle access on macroinvertebrate communities and deposited fine sediment levels, in four rivers of high/good and four rivers of moderate water quality status which drain, low gradient, calcareous grassland catchments in Ireland. We assessed the temporal variability in macroinvertebrates communities across two seasons, spring and autumn. Site specific impacts were evident which appeared to be influenced by water quality status and season. All four high/good water status rivers revealed significant downstream changes in community structure and at least two univariate metrics (total richness and EPT richness together with taxon, E and EPT abundance). Two of the four moderate water status rivers showed significant changes in community structure, abundance and richness metrics and functional feeding groups driven in the main by downstream increases in collectors/gatherers, shredders and burrowing taxa. These two moderate water status rivers had high or prolonged livestock activity. In view of these findings, the potential for some of these sites to achieve at least high/good water quality status, as set out in the EU Water Framework Directive, may be compromised. The results presented highlight the need for additional research to further define the site specific factors and livestock management practices, under different discharge conditions, that increase the risk of impact on aquatic ecology due to these cattle-river interactions.<br/
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