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Synchronization of Weighted Essentially Non-Oscillatory methods

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Communications in Computational Physics 2008年第6期4卷 56-71页

作者： Ellen m.taylor m.Pino martin Department of mechanical and Aerospace Engineering Princeton UniversityPrincetonNJ 08544USA

Weighted essentially non-oscillatory(WENO)methods have been developed to simultaneously provide robust shock-capturing in compressible fluid flow and avoid excessive damping of fine-scale flow features such as *** certain conditions in compressible turbulence,however,numerical dissipation remains unacceptably high even after optimization of the linear component that dominates in smooth *** the nonlinear error that remains,we demonstrate that a large fraction is generated by a“synchronization deficiency”that interferes with the expression of theoretically predicted numerical performance characteristics when the WENO adaptation mechanism is *** deficiency is illustrated numerically in simulations of a linearly advected sinusoidal wave and the Shu-Osher problem[***.,83(1989),pp.32-78].It is shown that attempting to correct this deficiency through forcible synchronization results in violation of *** conclude that,for the given choice of candidate stencils,the synchronization deficiency cannot be adequately resolved under the current WENO smoothness measurement technique.

关键词： Direct numerical simulation large eddy simulation compressible turbulence shock capturing.

Strategies towards statistically robust interpretations of in situ U-Pb zircon geochronology

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Geoscience Frontiers 2016年第4期7卷 581-589页

作者： Christopher J.Spencer Christopher L.Kirkland Richard J.m.taylor The Institute of Geoscience Research(TIGeR) Department of Applied GeologyWestern Australian School of MinesCurtin UniversityWA 6102Australia Centre for Exploration Targeting-Curtin Node Department of Applied GeologyWestern Australian School of MinesCurtin UniversityWA 6102Australia Australian Research Council Centre of Excellence for Core to Crust Fluid SystemsPerthWA 6102Australia

Zircon U-Pb geochronology has become a keystone tool across Earth science, arguably providing the gold standard in resolving deep geological time. The development of rapid in situ analysis of zircon （via laser ablation and secondary ionization mass spectrometry） has allowed for large amounts of data to be generated in a relatively short amount of time and such large volume datasets offer the ability to address a range of geological questions that would otherwise remain intractable （e.g. detrital zircons as a sedi- ment fingerprinting method）. The ease of acquisition, while bringing benefit to the Earth science com- munity, has also led to diverse interpretations of geochronological data. In this work we seek to refocus U -Pb zircon geochronology toward best practice by providing a robust statistically coherent workflow. We discuss a range of data filtering approaches and their inherent limitations （e.g. discordance and the reduced chi-squared; mSWD）. We evaluate appropriate mechanisms to calculate the most geologically appropriate age from both 238U/206pb and 207pb/206pb ratios and demonstrate the cross over position when chronometric power swaps between these ratios. As our in situ analytical techniques become progressively more precise, appropriate statistical handing of U-Pb datasets will become increasingly pertinent.

关键词： Zircon Geochronology U-Pb Geostatistics mSWD

The Representation of Soil moisture−Atmosphere Feedbacks across the Tibetan Plateau in CmIP6

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Advances in Atmospheric Sciences 2023年第11期40卷 2063-2081页

作者： Joshua TALIB Omar V.mÜLLER Emma J.BARTON Christopher m.taylor Pier Luigi VIDALE U.K.Centre of Ecology and Hydrology WallingfordOX108BBU.K. National Centre for Atmospheric Science ReadingRG66BBU.K. Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Centro de Estudios de Variabilidad y Cambio Climático(CEVARCAM)Facultad de Ingeniería y Ciencias HídricasUniversidad Nacional del LitoralSanta FeArgentina National Centre for Earth Observation WallingfordOX108BBU.K. Department of meteorology University of ReadingReadingRG66BBU.K.

Thermal processes on the Tibetan Plateau(TP)influence atmospheric conditions on regional and global *** this,previous work has shown that soil moisture−driven surface flux variations feed back onto the *** soil moisture is a source of atmospheric predictability,no study has evaluated soil moisture−atmosphere coupling on the TP in general circulation models(GCms).In this study,we use several analysis techniques to assess soil moisture−atmosphere coupling in CmIP6 simulations including:instantaneous coupling indices;analysis of flux and atmospheric behaviour during dry spells;and a quantification of the preference for convection over drier *** these metrics we partition feedbacks into their atmospheric and terrestrial *** with previous global studies,we conclude substantial inter-model differences in the representation of soil moisture−atmosphere coupling,and that most models underestimate such *** on dry spell analysis,most models underestimate increased sensible heat during periods of rainfall *** example,the model-mean bias in anomalous sensible heat flux is 10 W m−2(≈25%)smaller compared to *** dry-spell sensible heat fluxes lead to a weaker atmospheric *** also find that most GCms fail to capture the negative feedback between soil moisture and deep *** poor simulation of feedbacks in CmIP6 experiments suggests that forecast models also struggle to exploit soil moisture−driven *** improve the representation of land−atmosphere feedbacks requires developments in not only atmospheric modelling,but also surface processes,as we find weak relationships between rainfall biases and coupling indexes.

关键词： model evaluation land-atmosphere feedbacks Tibetan Plateau precipitation surface energy balance

Prograde and retrograde growth of monazite in migmatites:An example from the Nagercoil Block,southern India

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Geoscience Frontiers 2015年第3期6卷 373-387页

作者： Tim E.Johnson Chris Clark Richard J.m.taylor m.Santosh Alan S.Collins Department of Applied Geology The Institute for Geoscience Research(TIGeR)Curtin University School of the Earth Sciences and Resources China University of Geosciences(Beijing) Tectonics Resources and Exploration(TRaX)Department of Earth SciencesUniversity of Adelaide

Data from a migmatised metapelite raft enclosed within charnockite provide quantitative constraints on the pressure-temperature-time （P-T-t） evolution of the Nagercoil Block at the southernmost tip of peninsular India. An inferred peak metamorphic assemblage of garnet, K-feldspar, sillimanite, plagioclase, magnetite, ilmenite, spinel and melt is consistent with peak metamorphic pressures of 6-8 kbar and temperatures in excess of 900 ℃. Subsequent growth of cordierite and biotite record high-temperature retrograde decompression to around 5 kbar and 800 ℃. SHRImP U-Pb dating of magmatic zircon cores suggests that the sedimentary protoliths were in part derived from felsic igneous rocks with Palae- oproterozoic crystallisation ages. New growth of metamorphic zircon on the rims of detrital grains constrains the onset of melt crystallisation, and the minimum age of the metamorphic peak, to around 560 ma. The data suggest two stages of monazite growth. The first generation of REE-enriched monazite grew during partial melting along the prograde path at around 570 ma via the incongruent breakdown of apatite. Relatively REE-depleted rims, which have a pronounced negative europium anomaly, grew during melt crystallisation along the retrograde path at around 535 ma. Our data show the rocks remained at suprasolidus temperatures for at least 35 million years and probably much longer, supporting a long-lived high-grade metamorphic history. The metamorphic conditions, timing and duration of the implied clockwise P-T-t path are similar to that previously established for other regions in peninsular India during the Ediacaran to Cambrian assembly of that part of the Gondwanan supercontinent.

关键词： monazire migmatite Zircon Geochronology Phase equilibria modelling Gondwana

Clinical Cardiac mRI 2005

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温度及压力对滑动轴承气蚀磨损影响的实验研究

丛书名： medical Radiology

2005年

作者： Jan Bogaert Steven Dymarkowski Andrew m. taylor

来源：畅想之星图书光盘版（南... 评论

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机械科学与技术 2001年第4期20卷 565-566页

作者：安琦 C.m.taylor 华东理工大学机械学院上海200237 SchoolofmechanicalEngineering UniversityofLeedsLS29JTUK

采用超声振动原理建立了滑动轴承模拟气蚀实验装置 ,研究了温度及压力变化对滑动轴承气蚀磨损的影响。发现温度及压力的升高都会使滑动轴承的气蚀磨损增加。

关键词：滑动轴承气蚀温度压力磨损

Reappraising the P-T evolution of the Rogaland-Vest Agder Sector,southwestern Norway

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Geoscience Frontiers 2017年第1期8卷 1-14页

作者： Eleanore Blereau Tim E.Johnson Chris Clark Richard J.m.taylor Peter D.Kinny martin Hand Department of Applied Geology The Institute for Geoscience Research(TIGeR)Curtin University Centre for Tectonics Resources and Exploration(TRaX)School of Earth and Environmental SciencesUniversity of Adelaide

The Rogaland-Vest Agder Sector of southwestern Norway comprises high-grade metamorphic rocks intruded by voluminous plutonic bodies that include the ~1000 km^2 Rogaland Igneous Complex（RIC）.New petrographic observations and thermodynamic phase equilibria modelling of three metapelitic samples collected at various distances（30 km,10 km and ~ 10 m） from one of the main bodies of RIC anorthosite were undertaken to assess two alternative P-T-t models for the metamorphic evolution of the *** results are consistent with a revised two-phase *** metamorphism followed a clockwise P-T path reaching peak conditions of ~ 850-950 ℃ and ~7-8 kbar at ~1035 ma followed by high-temperature decompression to ~5 kbar at ~950 ma,and resulted in extensive anatexis and melt loss to produce highly residual *** emplacement of the RIC at ~930 ma caused regional-scale contact metamorphism that affected country rocks 10 km or more from their contact with the *** thermal overprint is expressed in the sample proximal to the anorthosite by replacement of sillimanite by coarse intergrowths of cordierite plus spinel and growth of a second generation of garnet,and in the intermediate（10 km） sample by replacement of sapphirine by coarse intergrowths of cordierite,spinel and *** formation of late biotite in the intermediate sample may suggest the rocks retained small quantities of melt produced by regional metamorphism and remained at temperatures above the solidus for up to 100 *** results are more consistent with an accretionary rather than a collisional model for the Sveconorwegian Orogen.

关键词： UHTPhase equilibria modellingRogaland Igneous ComplexTHERmOCALCSveconorwegian Orogen

STUDY ON THE INFLUENCES OF BUBBLY OIL ON THE CAVITATION EROSION IN JOURNAL BEARINGS OF ENGINES

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Chinese Journal of mechanical Engineering 2001年第4期14卷 378-380,384页

作者： An Qi (mechanical Engineering Department,East China University of Science and Technology) Priest m, taylor C m (The University of Leeds,LS2 9JT,UK) 华东理工大学上海 The University of Leeds 英国

A simulating experimental device for journal bearings of engines is established by use of the mechanism of ultrasonic vibration This device can make the pressure inside the oil film changed at ultrasonic frequency,which enable the specimen surface to be damaged by cavitation erosion in a comparatively short time Connecting with the bubbly oil producing device,this rig can investigate the influence of bubbly oil on the cavitation erosion Through detailed experimental research it is found that the bubbly oil decreases the cavitation erosion in journal bearings of engines This result is analyzed reasonably from mechanism of cavitation erosion.

关键词： Cavitation erosion Bubbly oil Journal bearing Engine

Healthcare staff well-being and use of support services during COVID-19:a UK perspective

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General Psychiatry 2021年第3期34卷 143-153页

作者： Anika R Petrella Luke Hughes Lorna A Fern Lisa monaghan Benjamin Hannon Adam Waters Rachel m taylor Cancer Division University College London Hospitals NHS Foundation TrustLondonUK Staff Psychological and Welfare Service University College London Hospitals NHS Foundation TrustLondonUK Centre for Nurse Midwife and AHP Led Research(CNMAR)University College London Hospitals NHS Foundation TrustLondonUK

Background The COVID-19 pandemic has drastically increased demands on healthcare workers(HCWs)leaving them vulnerable to acute psychological distress,burnout and post-traumatic *** response,supportive services in a central London hospital mobilised mental health support specifically for *** This rapid evaluation assessed HCW psychological welfare during the acute phase of the COVID-19 pandemic and their use of supportive services made *** During the acute phase of COVID-19(April to may 2020)all staff working for the hospital were invited to complete an online survey assessing well-being(self-rated health,moral distress exposure,symptoms of burnout and psychological distress)and use of available supportive services(awareness of,use and perceived helpfulness).Associations among personal characteristics and psychological well-being were explored using correlations and linear *** A total of 1127 staff participated in the rapid *** average,psychological distress was high(mean(SD):22(7.57))regardless of role,with 84%of this sample scoring above the general population mean(14.5).Nearly half of the sample reported feeling emotionally drained and a profile emerged displaying higher levels of psychological distress and burnout in those who were younger and exposed to morally distressing situations,with this group also exhibiting greater support service *** levels of burnout were associated with increased psychological distress when controlling for personal *** this acute phase of the pandemic,majority of staff used at least one service and rated it as *** HCWs experienced high levels of psychological distress requiring continued support as the COVID-19 pandemic *** HCWs were aware of supportive services,uptake *** order to mitigate the risk of burnout and post-traumatic stress,long-term,effective strategies that facilitate staff accessing support are urgently required.

关键词： distress younger staff