1,567 research outputs found

    The contribution of conveyed coal to mine heat problems

    Get PDF
    As coal mines get deeper, more mechanised and more productive the heat load on the ventilation system increases. In certain cases to the point where serious environmental problems may arise. To continue mining in these demanding conditions the sources of heat must be identified and evaluated so ameliorative measures may be taken. Due to the trend towards mining at greater rates and further from the shaft, mined coal on the conveyors is being recognised as a heat source of growing importance. This thesis describes its investigation. Reviews of heat sources, psychrometry,heat stress indices and heat transfer are included to provide a background framework. The evaluation of the heat released by conveyed coal itself consists of theoretical treatment and laboratory investigations of heat transfer through broken coal. A model conveyor and its instrumentation constructed in a duct are described along with underground measurements at mines. The information obtained from theoretical, laboratory and on site investigations is analysed and summarised to provide a basis for future prediction

    The contribution of conveyed coal to mine heat problems

    Get PDF
    As coal mines get deeper, more mechanised and more productive the heat load on the ventilation system increases. In certain cases to the point where serious environmental problems may arise. To continue mining in these demanding conditions the sources of heat must be identified and evaluated so ameliorative measures may be taken. Due to the trend towards mining at greater rates and further from the shaft, mined coal on the conveyors is being recognised as a heat source of growing importance. This thesis describes its investigation. Reviews of heat sources, psychrometry,heat stress indices and heat transfer are included to provide a background framework. The evaluation of the heat released by conveyed coal itself consists of theoretical treatment and laboratory investigations of heat transfer through broken coal. A model conveyor and its instrumentation constructed in a duct are described along with underground measurements at mines. The information obtained from theoretical, laboratory and on site investigations is analysed and summarised to provide a basis for future prediction

    Monitoring Frog Communities: An Application of Machine Learning

    Get PDF
    Automatic recognition of animal vocalisations would be a valuable tool for a variety of biological research and environmental monitoring applications . We report the development of a software system which can recognise the vocalisations of 22 species of frogs which occur in an area of Northern Australia. This software system will be used in unattended operation to monitor the effect on frog populations of the introduced Cane Toad. The system is based around classification of local peaks in the spectrogram of the audio signal using Quinlan's machine learning system, C4.5 (Quinlan 1993). Unreliable identifications of peaks are aggregated together using a hierarchical structure of segments based on the typical temporal vocalisation species' patterns. This produces robust system performance

    Risk assessment and implementation of risk reduction measures is not associated with increased transmission of SARS-CoV-2 compared with standard isolation at professional golf events.

    Get PDF
    Objectives The purpose of this prospective study was to report incidence and transmission of SARS-CoV-2, among professional golfers and essential support staff undergoing risk assessment and enhanced risk reduction measures when considered a close contact as opposed to standard isolation while competing on the DP World Tour during the 2021 season. Methods This prospective cohort study included all players and essential support staff participating in 26 DP World Tour events from 18 April 2021 to 21 November 2021. High-risk contacts were isolated for 10 days. Moderate-risk contacts received education regarding enhanced medical surveillance, had daily rapid antigen testing for 5 days, with reverse transcriptase-polymerase chain reaction (RT-PCR) tesing on day 5, mandated mask use and access to outside space for work purposes only. Low-risk contacts typically received rapid antigen testing every 48 hours and RT-PCR testing on day 5. Results The total study cohort compromised 13 394 person-weeks of exposure. There were a total of 30 positive cases over the study period. Eleven contacts were stratified as 'high risk'. Two of these subsequently tested positive for SARS-CoV-2. There were 79 moderate-risk contact and 73 low-risk contacts. One moderate-risk contact subsequently tested positive for SARS-CoV-2 but did not transmit the virus. All other contacts, remained negative and asymptomatic to the end of the tournament week. Conclusions A risk assessment and risk reduction-based approach to contact tracing was safe in this professional golf event setting when Alpha and Delta were the predominant variants. It enabled professional golfers and essential support staff to work

    Renewing the Exploration Approach for Mid-Enthalpy Systems: Examples from Northern England and Scotland

    Get PDF
    After a promising start in the 1970s and 80s, the UK rather fell behind other countries in the search for viable mid-enthalpy geothermal resources. This situation began to turn around in 2004, when the first of three deep geothermal exploration boreholes were drilled in northern England. What distinguished these from earlier drilling in Cornwall was the deliberate search for naturallyhigh permeability associated with major faults, especially those that have undergone strike-slip reactivation during the Cenozoic. Boreholes at Eastgate in the North Pennines targeted buried radiothermal granite, whereas the 1,821m-deep Science Central Borehole in Newcastle upon Tyne targeted a postulated deep sedimentary aquifer (the Fell Sandstones), which were inferred to be connected laterally to the granitic heat source by a major fault (the reactivation of the Iapetus geo-suture). The drilling was in both cases rewarded with impressive heat flows, and in the case of Eastgate with what is believed to be the highest permeability yet found in a deep granite batholith anywhere in the world. In parallel with these developments, a re-assessment was made of the preexisting geothermal heat flow database for the UK, applying newly-standardised correction protocols for palaeoclimatic and topographic distortions, which were found to be particularly marked in Scotland (where only shallow boreholes had been used to establish geothermal gradients in the original 1980s analysis), Similar prospects in northern England (similar to that drilled at Science Central) are now the focus of commercial exploration efforts. Appraisal of fault dispositions relative to the present-day maximum compressive stress azimuth are being used to identify the most promising areas for intersecting fault-related permeability at depth. New geophysical tools – most notably atomic dielectric resonance scanning – are also being appraised for their ability to directly detect features (such as hot brines) which are indicative of localised convection in target fault zones and aquifers

    Accelerometery and Heart Rate Responses of Professional Fast-Medium Bowlers in One-Day and Multi-Day Cricket

    Get PDF
    The physical demands of fast-medium bowling are increasingly being recognised, yet comparative exploration of the differing demands between competitive formats (i.e. one-day [OD] versus multi-day [MD] matches) remain minimal. The aim of this study was to describe in-match physiological profiles of professional fast-medium bowlers from England across different versions of competitive matches using a multivariable wearable monitoring device. Seven professional cricket fast-medium bowlers wore the BioharnessTM monitoring device during matches, over three sea-sons (>80 hours in-match). Heart Rate (HR) and Acceleromety (ACC) was compared across match types (OD, MD) and differ-ent in-match activity states (Bowling, Between over bowling, Fielding). Peak acceleration during OD bowling was significantly higher in comparison to MD cricket ([OD vs. MD] 234.1 ± 57.9 vs 226.6 ± 32.9 ct·episode-1, p < 0.05, ES = 0.11-0.30). Data for ACC were also higher during OD than MD fielding activities (p < 0.01, ES = 0.11-.30). OD bowling stimulated higher mean HR responses (143 ± 14 vs 137 ± 16 beats·min-1, p < 0.05, ES = 0.21) when compared to MD matches. This increase in OD crick-et was evident for both between over (129 ± 9 vs 120 ± 13 beats·min-1,p < 0.01, ES = 0.11-0.50) and during fielding (115 ± 12 vs 106 ± 12 beats·min-1, p < 0.01, ES = 0.36) activity. The increased HR and ACC evident in OD matches suggest greater acute physical loads than MD formats. Therefore, use of wearable technology and the findings provided give a valuable appreciation of the differences in match loads, and thus required physiological preparation and recovery in fast-medium bowlers

    In the dedicated pursuit of dedicated capital: restoring an indigenous investment ethic to British capitalism

    Get PDF
    Tony Blair’s landslide electoral victory on May 1 (New Labour Day?) presents the party in power with a rare, perhaps even unprecedented, opportunity to revitalise and modernise Britain’s ailing and antiquated manufacturing economy.* If it is to do so, it must remain true to its long-standing (indeed, historic) commitment to restore an indigenous investment ethic to British capitalism. In this paper we argue that this in turn requires that the party reject the very neo-liberal orthodoxies which it offered to the electorate as evidence of its competence, moderation and ‘modernisation’, which is has internalised, and which it apparently now views as circumscribing the parameters of the politically and economically possible

    Measuring Program Outcome

    Full text link
    The Progress Evaluation Scales (PES) provide an efficient measuring devicefor evaluating current functioning, setting treatment goals, and assessing change over time in clinically relevant aspects of personal, social, and community adjustment. The PES can be completed by patients, significant others, and therapists, making it possible to obtain various points of view of the outcome of mental health services. This article describes the seven domains measured by the PES and the underlying dimensions they were designed to tap, and presents the generalizability, validity, and usefulness of the scales as applied to an adult mental health center population.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/67322/2/10.1177_0193841X8100500402.pd

    Carbon dynamics of the Weddell Gyre, Southern Ocean

    Get PDF
    The accumulation of carbon within the Weddell Gyre and its exchanges across the gyre boundaries are investigated with three recent full-depth oceanographic sections enclosing this climatically important region. The combination of carbonmeasurements with ocean circulation transport estimates from a box inverse analysis reveals that deepwater transports associated with Warm Deep Water (WDW) and Weddell Sea Deep Water dominate the gyre’s carbon budget, while a dual-cell vertical overturning circulation leads to both upwelling and the delivery of large quantities of carbon to the deep ocean. Historical sea surface pCO2 observations, interpolated using a neural network technique, confirm the net summertime sink of 0.044 to 0.058 ± 0.010 Pg C / yr derived from the inversion. However, a wintertime outgassing signal similar in size results in a statistically insignificant annual air-to-sea CO2 flux of 0.002± 0.007 Pg C / yr (mean 1998–2011) to 0.012 ± 0.024 Pg C/ yr (mean 2008–2010) to be diagnosed for the Weddell Gyre. A surface layer carbon balance, independently derived fromin situ biogeochemical measurements, reveals that freshwater inputs and biological drawdown decrease surface ocean inorganic carbon levels more than they are increased by WDW entrainment, resulting in an estimated annual carbon sink of 0.033 ± 0.021 Pg C / yr. Although relatively less efficient for carbon uptake than the global oceans, the summertime Weddell Gyre suppresses the winter outgassing signal, while its biological pump and deepwater formation act as key conduits for transporting natural and anthropogenic carbon to the deep ocean where they can reside for long time scales
    • …
    corecore