39 research outputs found

    Failure Analysis And Repair Techniques For Turbomachinery Gears

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    LectureThis paper covers the use of gears in turbomachinery applications. It reviews the contents of the American Gear Manufacturers Association (AGMA) and American Petroleum Institute (API) standards. During the course of an engineer's career, he is called upon to examine gear failures. He must have a basic knowledge of gear failure modes and how they can be prevented. Sufficient background is necessary to detect early stages of gear damage so that they can be arrested before a complete outage occurs. When gears do fail or are damaged, there are various proven repair techniques available. These methods can save much downtime. Through the reuse of salvageable parts, substantial cost savings can be realized

    Thin Internal Wall Insulation, Measuring Energy Performance Improvements in Dwellings using Thin Internal Wall Insulation. Summary Report - BEIS

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    The benefits and risks associated with installing internal wall insulation (IWI) and thin internal wall insulation (TIWI) retrofits into solid wall homes are researched and evaluated for BEIS. In order to deliver this, a holistic approach was adopted and the project was split into four main sections, each of which has an accompanying Annex to this summary report: Annex A: Review of existing literature as well as primary investigations using house surveys, householder questionnaires and installer focus groups into the sociotechnical barriers to IWI and TIWI. Annex B: Technical evaluation of the performance of IWI and six novel TIWI retrofits installed in field trial solid wall Test Houses using before and after building performance evaluations. Annex C: Modelling of the impact on annual energy consumption, EPC rating, overheating risk, condensation risk and moisture accumulation made by IWI and TIWI retrofits in a range of UK house archetypes. Annex D: Laboratory testing of test walls using hygrothermal chambers to quantify the change in moisture and thermal performance of solid brick walls when they are insulated with IWI and TIWI to determine how weathe

    Capacity shortfalls hinder the performance of marine protected areas globally

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    Marine protected areas (MPAs) are increasingly being used globally to conserve marine resources. However, whether many MPAs are being effectively and equitably managed, and how MPA management influences substantive outcomes remain unknown. We developed a global database of management and fish population data (433 and 218 MPAs, respectively) to assess: MPA management processes; the effects of MPAs on fish populations; and relationships between management processes and ecological effects. Here we report that many MPAs failed to meet thresholds for effective and equitable management processes, with widespread shortfalls in staff and financial resources. Although 71% of MPAs positively influenced fish populations, these conservation impacts were highly variable. Staff and budget capacity were the strongest predictors of conservation impact: MPAs with adequate staff capacity had ecological effects 2.9 times greater than MPAs with inadequate capacity. Thus, continued global expansion of MPAs without adequate investment in human and financial capacity is likely to lead to sub-optimal conservation outcomes

    Genomic epidemiology of SARS-CoV-2 in a UK university identifies dynamics of transmission

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    AbstractUnderstanding SARS-CoV-2 transmission in higher education settings is important to limit spread between students, and into at-risk populations. In this study, we sequenced 482 SARS-CoV-2 isolates from the University of Cambridge from 5 October to 6 December 2020. We perform a detailed phylogenetic comparison with 972 isolates from the surrounding community, complemented with epidemiological and contact tracing data, to determine transmission dynamics. We observe limited viral introductions into the university; the majority of student cases were linked to a single genetic cluster, likely following social gatherings at a venue outside the university. We identify considerable onward transmission associated with student accommodation and courses; this was effectively contained using local infection control measures and following a national lockdown. Transmission clusters were largely segregated within the university or the community. Our study highlights key determinants of SARS-CoV-2 transmission and effective interventions in a higher education setting that will inform public health policy during pandemics.</jats:p
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