2,902 research outputs found

    Lubrication at physiological pressures by polyzwitterionic brushes

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    The very low sliding friction at natural synovial joints, which have friction coefficients of mu < 0.002 at pressures up to 5 megapascals or more, has to date not been attained in any human-made joints or between model surfaces in aqueous environments. We found that surfaces in water bearing polyzwitterionic brushes that were polymerized directly from the surface can have m values as low as 0.0004 at pressures as high as 7.5 megapascals. This extreme lubrication is attributed primarily to the strong hydration of the phosphorylcholine-like monomers that make up the robustly attached brushes, and may have relevance to a wide range of human-made aqueous lubrication situations

    Evaluation of the gn-->pi-p differential cross sections in the Delta-isobar region

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    Differential cross sections for the process gn-->pi-p have been extracted from MAMI-B measurements of gd-->pi-pp, accounting for final-state interaction effects, using a diagrammatic technique taking into account the NN and piN final-state interaction amplitudes. Results are compared to previous measurements of the inverse process, pi-p--> ng, and recent multipole analyses.Comment: 6 pages, 4 figures. v2: Further clarifications and minor changes. A new figure inserte

    Resistance to Digitisation: Curated Memory Cards Artefact

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    date-added: 2015-03-24 04:16:59 +0000 date-modified: 2015-03-24 04:16:59 +0000date-added: 2015-03-24 04:16:59 +0000 date-modified: 2015-03-24 04:16:59 +0000The act of networking in any context has some element of ceremonial performance attached to it. In an analogue world these performances have historically included the act of exchanging business cards. This ‘ceremony of networking’ has the potential to be altered by the emergence of new media, especially digital technology, displacing the old ceremony of business card exchanges and disrupting what can traditional be seen as networking. The history of business cards have shown that, despite several digital alternatives, they are still resistant to digitisation and so predominantly still physical and tangible. So, we sought to explore the ceremony around giving business cards as the sharing of ‘curated memory’, to better understand how and why we share and co-create curated memories with others. Including the sharing curated memories more generally, and the changing nature of networking, arising from the ever-increasing connectivity and digital embeddedness associated with the information age. Therefore, exploring the ceremony around needing, creating, sharing and using business cards, within different contexts and cultures. Also, identifying the tasks that people are trying to perform and optimise at different stages (before, during, and after) in a range of scenarios. Also, to explore how the ceremonies of networking might be significantly altered as a result of digital media and tools. The approach of using sets of cards around Who, How, Why and Where emerged from the need for a tool that could build narratives around the considerable diversity of the disjointed scenarios of networking we observed. So, the cards provide a reference by which to share general understanding in an entertaining and easily accessible manner. Second, provides a tool to summarise narratives from the scenarios we observed, and that we could then use to create new scenarios to explore insights such as post-meeting curation of ‘shared memories’ when networking. Third, define a number of ‘games’ to help anyone explore how to better understand and utilise aspects of networking in their current approaches, and challenge them to develop new approaches. Therefore, generating debate and self-reflection on the ways players use business cards themselves

    London Creative and Digital Fusion

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    date-added: 2015-03-24 04:16:59 +0000 date-modified: 2015-03-24 04:16:59 +0000date-added: 2015-03-24 04:16:59 +0000 date-modified: 2015-03-24 04:16:59 +0000The London Creative and Digital Fusion programme of interactive, tailored and in-depth support was designed to support the UK capital’s creative and digital companies to collaborate, innovate and grow. London is a globally recognised hub for technology, design and creative genius. While many cities around the world can claim to be hubs for technology entrepreneurship, London’s distinctive potential lies in the successful fusion of world-leading technology with world-leading design and creativity. As innovation thrives at the edge, where better to innovate than across the boundaries of these two clusters and cultures? This booklet tells the story of Fusion’s innovation journey, its partners and its unique business support. Most importantly of all it tells stories of companies that, having worked with London Fusion, have innovated and grown. We hope that it will inspire others to follow and build on our beginnings.European Regional Development Fund 2007-13

    Extended Partial-Wave Analysis of piN Scattering Data

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    We present results from a comprehensive partial-wave analysis of pi+-p elastic scattering and charge-exchange data, covering the region from threshold to 2.6 GeV in the lab pion kinetic energy, employing a coupled-channel formalism to simultaneously fit pi-p-->eta n data to 0.8 GeV. Our main result, solution SP06, utilizes a complete set of forward and fixed-t dispersion relation constraints applied to the piN elastic amplitude. The results of these analyses are compared with previous solutions in terms of their resonance spectra and preferred values for couplings and low-energy parameters.Comment: 21 pages, 11 figure

    η\eta-meson in nuclear matter

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    The η\eta-nucleon (η\etaN) interactions are deduced from the heavy baryon chiral perturbation theory up to the next-to-leading-order terms. Combining the relativistic mean-field theory for nucleon system, we have studied the in-medium properties of η\eta-meson. We find that all the elastic scattering η\etaN interactions come from the next-to-leading-order terms. The η\eta N sigma term is found to be about 280±\pm130 MeV. The off-shell terms are also important to the in-medium properties of η\eta-meson. On application of the latest determination of the η\etaN scattering length, the ratio of η\eta-meson effective mass to its vacuum value is near 0.84±0.0150.84\pm0.015, while the optical potential is about (83±5)-(83\pm5) MeV, at the normal nuclear density.Comment: 8 pages, 3 figures, to appear in PRC, many modification

    Self-adhesive electrode applied to ZnO nanorod-based piezoelectric nanogenerators

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    ZnO nanorod-based piezoelectric devices have gained wide attention in energy harvesting systems as they can be processed at low temperatures onto flexible plastic substrates, giving a good potential for low cost. However, the vacuum-evaporated, precious metal contacts remain a high-cost element of the devices. This paper discusses the use of transparent conductive adhesives (TCAs) as an alternative top contact that is free from both vacuum-evaporation and precious metals. TCA films of various thicknesses were tape-cast onto nickel microgrid on PET substrates and adhered using low-pressure cold-lamination to bond the adhesive component of the TCA to piezoelectric generators with the final device structure of PET/ITO/ZnO-seed/ZnO-nanorods/CuSCN/PEDOT:PSS/TCA. The piezoelectric performances of the devices were compared by measuring output voltage in open-circuit and maximum power output across a range of resistive loads. The voltage output was observed to rise with increasing TCA thickness, reaching a maximum value of 0.72 V generated with 110 µm of TCA as top contact. However, the higher resistance due to increased TCA thickness led to decreased power output; a maximum calculated power of 0.25 μW was obtained from the device with the thinnest TCA layer of 22 µm. Finally, the performance of piezoelectric nanogenerators with TCA contacts were compared to a control device with an evaporated gold contact

    Overview of Pre-Congestion Notification Encoding

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    The objective of Pre-Congestion Notification (PCN) is to protect the quality of service (QoS) of inelastic flows within a Diffserv domain. On every link in the PCN-domain, the overall rate of PCN-traffic is metered, and PCN-packets are appropriately marked when certain configured rates are exceeded. Egress nodes provide decision points with information about the PCN-marks of PCN-packets that allows them to take decisions about whether to admit or block a new flow request, and to terminate some already admitted flows during serious pre-congestion. The PCN working group explored a number of approaches for encoding this pre-congestion information into the IP header. This document provides details of those approaches along with an explanation of the constraints that apply to any solution
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