5,074 research outputs found

    An innovation integrated approach to testing motorcycle drive chain lubricants

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    An innovative integrated approach to the testing and comparison of motorcycle drive chain lubricants is presented. This is a novel way of testing the lubrication by using loaded operating chains and sprockets. A test rig has been designed to operate chains and sprockets in a clean environment and allow direct comparison between different lubricants. The advantage of this method over previous techniques is that it allows the differentiation of lubricants in a more controlled operating environment and evaluates the overall lubricant performance as opposed to individual properties. The lubricants tested were a wax spray, PTFE spray and drip fed light oil. The test rig allowed measurement of the power saved by the lubricant in running the chains and sprockets. Chain length and component masses were also taken before and after running the chains and sprockets under load on the test rig. The results clearly show that any lubricant is preferable to none. The drip fed oil provided the greatest power saving and wear protection between the chain rollers and pins and the spray lubricants provided the highest level of protection between rollers and sprocket

    Influence of gasoline engine lubricant on tribological performance, fuel economy and emissions

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    The requirement for increased performance, improved fuel economy and reduced emissions is constantly sustaining the demand for research into combustion, fuels and lubricants. Due to the nature of the operation of an engine and the current market climate the lubricant not only has to respond to these requirements, but also to changes in engine design, fuelling methods and fuel types, increased power densities and developments in emissions formation and after-treatment. This paper will describe advances made at the authors’ institution to elucidate the influence of gasoline engine lubricant on tribological performance, fuel economy and emissions, giving examples of work undertaken and then look to future possible lubricant demands

    Integrated Serologic Surveillance of Population Immunity and Disease Transmission.

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    Antibodies are unique among biomarkers in their ability to identify persons with protective immunity to vaccine-preventable diseases and to measure past exposure to diverse pathogens. Most infectious disease surveillance maintains a single-disease focus, but broader testing of existing serologic surveys with multiplex antibody assays would create new opportunities for integrated surveillance. In this perspective, we highlight multiple areas for potential synergy where integrated surveillance could add more value to public health efforts than the current trend of independent disease monitoring through vertical programs. We describe innovations in laboratory and data science that should accelerate integration and identify remaining challenges with respect to specimen collection, testing, and analysis. Throughout, we illustrate how information generated through integrated surveillance platforms can create new opportunities to more quickly and precisely identify global health program gaps that range from undervaccination to emerging pathogens to multilayered health disparities that span diverse communicable diseases

    Towards Large-scale Inconsistency Measurement

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    We investigate the problem of inconsistency measurement on large knowledge bases by considering stream-based inconsistency measurement, i.e., we investigate inconsistency measures that cannot consider a knowledge base as a whole but process it within a stream. For that, we present, first, a novel inconsistency measure that is apt to be applied to the streaming case and, second, stream-based approximations for the new and some existing inconsistency measures. We conduct an extensive empirical analysis on the behavior of these inconsistency measures on large knowledge bases, in terms of runtime, accuracy, and scalability. We conclude that for two of these measures, the approximation of the new inconsistency measure and an approximation of the contension inconsistency measure, large-scale inconsistency measurement is feasible.Comment: International Workshop on Reactive Concepts in Knowledge Representation (ReactKnow 2014), co-located with the 21st European Conference on Artificial Intelligence (ECAI 2014). Proceedings of the International Workshop on Reactive Concepts in Knowledge Representation (ReactKnow 2014), pages 63-70, technical report, ISSN 1430-3701, Leipzig University, 2014. http://nbn-resolving.de/urn:nbn:de:bsz:15-qucosa-15056

    Extraction and tribological investigation of top piston ring zone oil from a gasoline engine

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    With tightening emission regulations, increased expected fuel economy, and longer drain intervals impacting on lubricant formulation, greater understanding of how oil degrades in an automotive engine is becoming ever more important. Equally significant is the effect that this degraded lubricant has on the tribological operation of the engine, particularly its overall internal friction and component wear. In a previous paper, four tests to degrade oil in a single cylinder engine were reported [1]. These tests were set up such that the lubricating oil was degraded in the ring pack before returning to the sump, where it was sampled and chemical and rheological analysis undertaken. This paper reports the extension of this work using the same Hydra engine and describes how oil has additionally been extracted from the rear of the top piston ring during engine operation. This extracted oil has then been subjected to similar analysis as the sump oil samples in the previous tests, along with additional analysis to look at the tribological properties of the oil using tribometers. The results clearly show significant differences in the rheological, tribological, and chemical properties of the fresh oil and used sump oil samples when compared with the top ring zone (TRZ) oil samples, particularly the effect of load on the levels of volatiles present in the TRZ samples and their effect on traction and friction coefficient values during tribological testing

    Sensation Seeking and Perceived Need for Structure Moderate Soldiers’ Well-Being Before and After Operational Deployment

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    This study examined associations between sensation seeking and perceived need for structure, and changes in reported well-being among deployed soldiers. Participants (n = 167) were assessed before and after a six-month deployment to south Afghanistan. Results indicated that although well-being declined in the soldier sample as a whole following deployment, the degree of decrease was significantly different among soldiers with different personality profiles. Differences were moderated by soldiers’ level of sensation seeking and perceived need for structure. Results are discussed in terms of a person-environment fit theory in the context of preparation and rehabilitation of deployed military personnel

    A Heavenly Example of Scale Free Networks and Self-Organized Criticality

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    The sun provides an explosive, heavenly example of self-organized criticality. Sudden bursts of intense radiation emanate from rapid rearrangements of the magnetic field network in the corona. Avalanches are triggered by loops of flux that reconnect or snap into lower energy configurations when they are overly stressed. Our recent analysis of observational data reveals that the loops (links) and footpoints (nodes), where they attach on the photosphere, embody a scale free network. The statistics of the avalanches and of the network structure are unified through a simple dynamical model where the avalanches and network co-generate each other into a complex, critical state. This particular example points toward a general dynamical mechanism for self-generation of complex networks.Comment: Submitted to proceedings for the Latin American Workshop on Nonlinear Phenomena, Salvador, Brazil (2003

    Flux and field line conservation in 3--D nonideal MHD flows: Remarks about criteria for 3--D reconnection without magnetic neutral points

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    We make some remarks on reconnection in plasmas and want to present some calculations related to the problem of finding velocity fields which conserve magnetic flux or at least magnetic field lines. Hereby we start from views and definitions of ideal and non-ideal flows on one hand, and of reconnective and non-reconnective plasma dynamics on the other hand. Our considerations give additional insights into the discussion on violations of the frozen--in field concept which started recently with the papers by Baranov & Fahr (2003a; 2003b). We find a correlation between the nonidealness which is given by a generalized form of the Ohm's law and a general transporting velocity, which is field line conserving.Comment: 9 pages, 2 figures, submitted to Solar Physic

    Since 1843: in the making, 8 January - 7 February 2014

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    Catalogue published to accompany the exhibition of the same name held at Nottingham Trent University (Newton, Bonington and Waverley buildings) from 8 January-7 February 2014. The exhibition commenced a series of events to celebrate the 170th anniversary of what in 1843 was named the Nottingham School of Design, and is now the School of Art & Design at Nottingham Trent University

    Lubricant degradation, transport and the effect of extended oil drain intervals on piston assembly tribology

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    There are ever increasing demands on lubricant manufacturers to meet governmental legislation and customer needs by improving fuel economy, engine durability and exhaust system compatibility as shown by the introduction of GF4 and move towards GF5 specification oils. This has created an ever increasing need to understand how oil degrades in an engine and how this degraded oil affects piston assembly tribology. This review conference paper will give an overview of a collaborative project that has been undertaken to further enhance the understanding of how lubricant degrades in an operating engine, its transport through the engine and effect upon piston assembly tribology
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