1,318 research outputs found
Results of a UK industrial tribological survey
During the summer of 2012, the National Centre for Advanced Tribology at Southampton (nCATS) undertook a UK-wide industrial tribological survey in order to assess the explicit need for tribological testing within the UK. The survey was designed and implemented by a summer intern student, Mr Simon King, under the supervision of Drs John Walker and Terry Harvey and supported by the director of nCATS, Professor Robert Wood. The survey built upon on two previous tribological surveys conducted through the National Physical Laboratory (NPL) during the 1990’s. The aim was to capture a snapshot of the current use of tribological testing within UK industry and its perceived reliability in terms of the test data generated. The survey also invited participants to speculate about how UK tribology could improve its approach to testing. The survey was distributed through the nCATS industrial contact list, which comprises of over 400 contacts from a broad spectrum of commercial industries. The Institute of Physics (IOP) tribology group also assisted by distributing the survey to its membership list. A total of 60 responses were received for the survey, out of which 39 had fully completed the questionnaire. Participants came from a broad spread of industrial backgrounds, with the energy sector having the highest representation. Only 40% of respondents were dedicated tribologists/surface engineers, again reflecting the multi-disciplinary nature of the field. It was found that the companies that had the highest annual turnover also appeared to expend the most on tribology. The majority of respondents indicated that as a percentage of turnover tribology accounted for less than 1%, however the lack of hard figures only for tribology make this a conservative estimate. The greatest concern in relation to tribology of those who responded was the cost; however the influence of legislation and product reliability were also driving factors. Abrasive wear was still considered the number one tribological wear mechanism, with sliding contacts ranking as the most common type of wear interface. Metallic and hard coated surfaces were the most commonly encountered type of material suffering from tribological wear phenomena. Laboratory scale testing was a significant part of introducing a new tribological component, however component specific testing was considered the most reliable form of testing a new component over standardised test geometries. Overall there appeared to be much potential for improving the reliability of tribological test data, with most respondents indicating that simply more testing was not the best perceived approach to improving tribological data but rather more reliable, representative tests with improved knowledge capture. Most companies possessed an internal database to assist them with tribological information; however, many also expressed a strong desire for the use of a commercial or national database, although the format this might take was less clear. Opinions appeared split as to whether there would be a collective willingness to contribute to a centralised database, presumably on the grounds on the sensitivity of data
Ensemble Concerts: Symphonic Band and Symphonic Winds, October 5, 2023
Center for the Performing ArtsOctober 5, 2023Thursday Evening8:00 p.m
Infection dynamics: from organ to host population
A symposium discussing collaborative research work on infectious diseases dynamics was held at Queens' College, University of Cambridge on 25 October 2006
Ensemble Concerts: Symphonic Band and Symphonic Winds, November 30, 2023
Center for the Performing ArtsNovember 30, 2023Thursday Evening8:00 p.m
Diamond like carbon coatings for potential application in biological implants – a review
Production of wear debris has been linked to the failure of numerous hip implants. With the current focus on increasing the implant longevity, thus wear and corrosion resistance is important. Hard coatings have the potential to reduce the wear and corrosion. Diamond like Carbon (DLC) coatings exhibit properties that could make them viable for implants. This paper critically reviews previously published research into usage of DLC coatings for implants. Overall DLCs seem to be an effective coating for implants but with the variance in results, further testing is required for clarification of us
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Particulate matter chemistry and dynamics in the Twilight Zone at VERTIGO ALOHA and K2 Sites
Understanding particle dynamics in the 'Twilight Zone' is critical to prediction of the ocean's carbon cycle. As part of the VERTIGO (VERtical Transformations In the Global Ocean) project, this rarely sampled regime extending from the base of the euphotic layer to 1000 m, was characterized by double-paired day/night Multiple Unit Large Volume in-situ Filtration System (MULVFS) deployments and by {approx}100 high-frequency CTD/transmissometer/turbidity sensor profiles. VERTIGO studies lasting three weeks, contrasted oligotrophic station ALOHA (22.75{sup o}N 158{sup o}W), sampled in June-July 2004, with a biologically productive location (47{sup o}N 161{sup o}E) near station K2 in the Oyashio, occupied July-August 2005. Profiles of major and minor particulate components (C{sub org}, N, P, Ca, Si, Sr, Ba, Mn) in <1, 1-51, and >51 {micro}m size fractions, in-water optics, neutrally buoyant sediment trap (NBST) fluxes, and zooplankton data were intercompared. MULVFS total C{sub org} and C-Star particle beam attenuation coefficient (C{sub P}) were consistently related at both sites with a 27 {micro}M m{sup -1} conversion factor. 26 At K2, C{sub P} profiles further showed a multitude of transient spikes throughout the water column and spike abundance profiles closely paralleled the double peaked abundance profiles of zooplankton. Also at K2, copepods contributed {approx}40% and 10%, night and day, respectively to >51 {micro}m C{sub org} of MULVFS samples in the mixed layer, but few copepods were collected in deeper waters; however, non-swimming radiolarians were quantitatively sampled. A recent hypothesis regarding POC differences between pumps and bottles is examined in light of these results. Particulate >51 {micro}m C{sub org}, N, and P at both ALOHA and K2 showed strong attenuation with depth at both sites. Notable at ALOHA were unusually high levels of >51 {micro}m Sr (up to 4 nM) in the mixed layer, a reflection of high abundances of SrSO{sub 4} precipitating Acantharia. Notable at K2 were major changes in water column inventories of many particulate components to 700 m over 10 days. Carbon mass balance, with the consideration of particle inventory changes included, indicated that over 98% and 96% of primary produced C{sub org} was remineralized shallower than 500 m at ALOHA and K2, respectively. Production of CaCO3 was estimated to be {approx}0.06, 0.89 and 0.02 mmols m{sup -2} d{sup -1} at ALOHA and at K2 during two separate week long study periods, respectively. Similarly, Si production was estimated to be {approx}0.08, 10.7, and 4.2 mols m{sup -2} d{sup -1}. An estimated 50% and 65% of produced Si was remineralized by 500m at ALOHA and K2, respectively. Little carbonate dissolution was seen in the upper 500 m at ALOHA, a reflection of 400% super saturation of surface waters and the 700 m deep saturation horizon. Over 92% of produced CaCO{sub 3} was dissolved shallower than 500 m at K2 and biological enhancement of dissolution was readily apparent in waters above the 200 m calcite saturation horizon
An agent-based traffic simulation framework to model intelligent virtual driver behaviour
This paper presents an agent-based traffic simulation framework that supports intelligent virtual driver behaviour. The framework exploits concepts used in Artificial Life (ALife), Artificial Intelligence (AI) and Agent technology to model the inherent unpredictability and autonomous behaviour of drivers within traffic simulation models. Each driver agent in our system contains knowledge and a decision-making mechanism, both of which are based on heuristics. This approach replaces some of the prescriptive nature of driving simulation models by allowing behaviours to emerge as a result of individual driver agent interactions. The framework also contributes to accident analysis by improving current limitations in which accident investigation methods concentrate on the events themselves, rather than pre-crash influences. Within this context, the framework provides an opportunity to increase the understanding of accident causation factors, to examine alternative traffic scenarios (what if analyses) and methodology to obtain quantitative estimates of accident risk. Current implementation results show that driver agents within the integrated simulation are able to perceive other drivers’ speeds and distances, avoid collisions, perform realistic vehicle following, and demonstrate emergent traffic flow. A major application area for this framework includes the evaluation of vehicle, highway and road user factors that precede a collision, or near misses
Ensemble Concerts: Symphonic Band and Symphonic Winds, October 6, 2022
Center for the Performing ArtsOctober 6th, 2022Thursday Evening8:00 p.m
University Band, Symphonic Band, Symphonic Winds, November 16, 2021
Center for the Performing Arts
November 16, 2021
Tuesday Evening
7:00 p.m
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