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Time-first approach for land cover mapping using big Earth observation data time-series in a data cube-a case study from the Lake Geneva region(Switzerland)

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Big Earth Data 2024年第3期8卷 435-466页

作者： gregory Giuliani Institute for Environmental Sciences EnviroSPACE labUniversity of GenevaGenevaSwitzerland United nations Environment Programme Division of Early Warning and AssessmentGenevaSwitzerland

Accurate,consistent,and high-resolution Land Use&Cover(LUC)information is fundamental for effectively monitoring landscape dynamics and better apprehending drivers,pressures,state,and impacts on land ***,the availability of such national products with high thematic accuracy is still limited and consequently researchers and policymakers are constrained to work with data that do not necessarily reflect on-the-ground realities impending to correctly capture details of landscape features as well as limiting the identification and quantification of drivers and rate of ***,we took advantage of the Switzerland’s official LUC statistical sampling survey and dense time-series of Sentinel-2 data,combining them with Machine and Deep Learning methods to produce an accurate and high spatial resolution land cover map over the Lake Geneva *** suggest that time-first approach is a valuable alternative to space-first approaches,accounting for the intra-annual variability of classes,hence improving classification *** demonstrate that Deep Learning methods outperform more traditional Machine Learning ones such as Random Forest,providing more accurate predictions with lower *** produced land cover map has a high accuracy,an improved spatial resolution,while at the same time preserving the statistical significance(*** proportion)of the official national *** work paves the way towards the objective to produce a yearly high resolution land cover map of Switzerland and potentially implement a continuous land change monitoring *** further work is required to properly address challenges such as the need for increased temporal resolution for LUC information or the quality of training samples.

关键词： Land cover Sentinel-2 timeseries SITS Arealstatistik

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Global weirding at mass extinction horizons

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national Science Review 2024年第1期11卷 10-12页

作者： gregory J.Retallack Department of Earth Sciences University of Oregon

A strong motivation for studying mass extinctions is understanding how current climatic and biodiversity crises will affect creatures living on land such as ourselves. Perhaps the question is: how bad can it get? In that case, terrestrial Permian-Triassic mass extinctions are an irresistible worst-case scenario [1].

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Change in observed long-term greening across Switzerlandevidence from a three decades nDVI time-series and its relationship with climate and land cover factors

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Big Earth Data 2024年第1期8卷 1-32页

作者： Claire Obuchowicz Charlotte Poussin gregory Giuliani Institute for Environmental Sciences EnviroSPACE labUniversity of GenevaGenevaSwitzerland Institute for Environmental Sciences University of GenevaGenevaSwitzerland

Environmental changes are significantly modifying terrestrial vegetation dynamics,with serious consequences on Earth system functioning and provision of ecosystem *** conditions are an essential element underpinning global sustainability frameworks,such as the Sustainable Development Goals(SDGs),requiring effective solutions to assess the impacts of changing land conditions induced by various driving *** the global scale,long-term increase of vegetation greening has been widely reported notably in seasonally snow-covered ecosystems as a response to warming ***,greening trends at the national scale have received less attention,although countries like Switzerland are prone to important changing climate ***,we used a 35-year satellite-derived annual and seasonal time-series of normalized Difference Vegetation Index(nDVI)to assess vegetation greenness evolution at different spatial and temporal scales across Switzerland and related them to temperature,precipitation,and land cover to investigate possible responses of changing climatic *** indicate that there is a statistically significant greening trend at the national scale with an nDVI mean increasing slope of 0.6%/year for the 61%significant pixels across *** particular,the seasonal mean nDVI shows an important break for winter,autumn and spring seasons starting from 2010,potentially indicating a critical point of changing land *** biogeographical scale,we observed an apparent clustering(Jura-Plateau;northern-Southern Alps;Eastern-Western Alps)related to landscape characteristics,while forested land cover classes are more responsive to nDVI ***,the nDVI values are mostly a function of temperature at elevations below the tree line rather than *** findings suggest that multi-annual and seasonal nDVI can be a valuable indicator to monitor vegetation conditions at different scales and can provide complementary observati

关键词： Landsat climate land cover nDVI anomaly

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A numerical model to simulate the transient frictional viscoelastic sliding contact

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Friction 2024年第2期12卷 319-339页

作者： Dongze WAnG gregory de BOER Anne nEVILLE Ali GHAnBARZADEH School of Mechanical Engineering University of LeedsLeeds LS29JTUK

Sliding motion has always been one of the major concerns when it comes to the analysis of viscoelastic contact problems.A new model simulating the transient sliding contact of smooth viscoelastic surfaces is developed in this *** taking the dry contact friction and the coupling between shear tractions and normal pressure into account,the effect of the early partial slip period,which is often neglected in the study of viscoelastic sliding contact problems,is investigated *** with solutions based on the frictionless assumption,the steady-state pressure profile is found to be slightly different under the effect of the partial slip regime,including a lower peak pressure and the shift of the contacting region in the direction opposite to the sliding ***,the time required for the viscoelastic contact to reach its steady state is delayed owing to the partial slip period preceding the global sliding motion.

关键词： contact mechanics frictional sliding viscoelasticity viscoelastic friction

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Trends in oxycodone and oxycodone-containing analgesics administration for back pain in emergency departments in the USA(2007–2018)

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World Journal of Emergency Medicine 2024年第3期15卷 169-174页

作者： Jonathan Chabon Jemer Garrido Deanna Schreiber-gregory Jefferson Drapkin Sergey Motov Department of Emergency Medicine Maimonides Medical CenterBrooklyn 11219USA

BACKGROUnD:To describe trends in oxycodone and oxycodone-containing analgesic prescribing for the treatment of back pain among adults in emergency departments(EDs) in the USA from 2007 to ***:Data were gathered from the national Hospital Ambulatory Medical Care Survey(nHAMCS) from 2007 to *** study population included individuals of all ages presenting to USA *** nHAMCS reasons for visit and oxycodone drug ID codes were used to isolate patients with back *** main outcome was the proportion of oxycodone and oxycodone-containing analgesics prescribed for back pain in the EDs over the specified time ***:There was a relative decrease in the overall administration of oxycodone for back pain in the EDs by 62.3% from 2007(244,000 visits) to 2018(92,000 visits).The proportion of ED patients prescribed with oxycodone-containing analgesics for back pain increased among patients aged 45 years and older(from 43.8% to 57.6%),female patients(from 54.5% to 62.0%),black patients(from 22.5% to 30.4%),and Hispanic/Latino patients(from 9.4% to 19.6%).Oxycodone/acetaminophen was most prescribed and accounted for 90.2% of all oxycodone-containing analgesics in 2007,with a decrease to 68.5% in *** oxycodone was the second most prescribed medication,accounting for 6.1% in 2007 and 31.5% in ***:The overall number of oxycodone-containing analgesics decreased significantly from 2007 to ***,that number trended upward in 45-year-old and older,female,black,or Hispanic/Latino patients from 2007 to *** total amount of pure oxycodone increased significantly from 2007 to 2008.

关键词： Oxycodone Back pain Emergency department

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Is salmonid migration at risk from chemical information disruption?

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Aquaculture and Fisheries 2024年第3期9卷 378-387页

作者： Keith B.Tierney gregory G.Pyle Biological Sciences College of Natural and Applied SciencesEdmontonABT6G 2E9Canada School of Public Health College of Health SciencesEdmontonABT6G 1C9Canada Department of Biological Sciences University of LethbridgeLethbridgeABT1K 3M4Canada

Good information is the basis for good *** many invaluable salmon species,chemical information is necessary to guide and fine-tune their migrations to and from freshwater mating grounds.A problem is that salmon of the current world are running a gauntlet of toxic chemicals arising from diverse anthropogenic inputs and these chemicals are known to disrupt *** is sufficient evidence that effluents from cities,mines,agriculture and industry contain chemicals that can rapidly,and sometimes irreversibly,impair the olfactory sense that salmon use to gather *** toxic inputs may not only be strong enough to impair migration,but be strong enough to redirect salmon away from their *** is also evidence that some synthetic chemicals may serve as the basis for ‘new’ information and be useful in making correct migratory *** the plus side,there are examples of new regulations that limit the input of chemicals of known olfactory toxicity,but on the minus side,increased urbanization and global climate change will likely increase the number and/or severity of some neurotoxic *** we identify the specific avenues of chemical risks to information disruption and in so doing prioritize and rank the risks to migrating *** data collected here can be used to lay the foundation for modelling the effects of anthropogenic inputs on information disruption in diverse salmonid species from around the world and therefore help secure their longevity in a changing chemical environment.

关键词： Salmon migration Ocean ranching Chemical information disruption Homing disruption Olfactory toxicity

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Diagnosing health in composite battery electrodes with explainable deep learning and partial charging data

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Energy and AI 2024年第2期16卷 256-268页

作者： Haijun Ruan niall Kirkaldy gregory J.Offer Billy Wu Dyson School of Design Engineering Imperial College LondonSW72AZLondonUK Centre for E-Mobility and Clean Growth Research Coventry UniversityCoventryCV15FBUK Department of Mechanical Engineering Imperial College LondonSW72AZLondonUK The Faraday Institution Harwell Science and Innovation CampusOX110RADidcotUK

Lithium-ion batteries with composite anodes of graphite and silicon are increasingly being used. However, their degradation pathways are complicated due to the blended nature of the electrodes, with graphite and silicon degrading at different rates. Here, we develop a deep learning health diagnostic framework to rapidly quantify and separate the different degradation rates of graphite and silicon in composite anodes using partial charging data. The convolutional neural network (Cnn), trained with synthetic data, uses experimental partial charging data to diagnose electrode-level health of tested batteries, with errors of less than 3.1% (corresponding to the loss of active material reaching ∼75%). Sensitivity analysis of the capacity-voltage curve under different degradation modes is performed to provide a physically informed voltage window for diagnostics with partial charging data. By using the gradient-weighted class activation mapping approach, we provide explainable insights into how these Cnns work;highlighting regions of the voltage-curve to which they are most sensitive. Robustness is validated by introducing noise to the data, with no significant negative impact on the diagnostic accuracy for noise levels below 10 mV, thus highlighting the potential for deep learning approaches in the diagnostics of lithium-ion battery performance under real-world conditions. The framework presented here can be generalised to other cell formats and chemistries, providing robust and explainable battery diagnostics for both conventional single material electrodes, but also the more challenging composite electrodes.

关键词： Lithium-ion battery Composite electrode Silicon Degradation diagnostic Explainable deep learning Partial charging

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High Temperature Iron Ethylene Polymerization Catalysts Bearing n,n,n'-2-(1-(2,4-Dibenzhydryl-6-fluorophenylimino)ethyl)-6-(1-(arylphenylimino)ethyl)pyridines

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Chinese Journal of Polymer Science 2024年第2期42卷 188-201,I0007页

作者： Chantsalnyam Bariashir Qiu-Yue Zhang Bayasgalan Ulambayar gregory A.Solan Tong-Ling Liang Wen-Hua Sun Institute of Chemistry and Chemical Technology Mongolian Academy of SciencesUlaanbaatar13330Mongolia Key Laboratory of Engineering Plastics and Beijing national Laboratory for Molecular Science Institute of ChemistryChinese Academy of SciencesBeijing100190China Department of Chemistry University of LeicesterUniversity RoadLeicesterLE17RHUK State Key Laboratory for Oxo Synthesis and Selective Oxidation Lanzhou Institute of Chemical PhysicsChinese Academy of SciencesLanzhou730000China

The n,n,n'-ferrous chloride complexes,[2-{CMen(2,4-(CHPh)_(2)-6-FC_(6)H_(2))}-6-(CMenAr)C_(5)H_(3)n]FeCl_(2)(Ar=2,6-Me_(2)C_(6)H_(3) Fe1,2,6-Et_(2)C_(6)H_(3)Fe2,2,6-^(i)Pr_(2)C_(6)H_(3) Fe3,2,4,6-Me_(3)C_(6)H_(2) Fe4 and 2,6-Et_(2)-4-MeC_(6)H_(2) Fe5),each possessing one n-2,4-dibenzhydryl-6-fluorophenyl group,were readily synthesized from their respective unsymmetrical bis(imino)pyridines,*** identification of Fe2 highlighted the variation in the steric properties provided by the dissimilar n-aryl *** pre-treatment with either MAO or MMAO,complexes Fe1-Fe5 all displayed,at an operating temperature of 80℃,high activities for ethylene polymerization with levels falling in the order:Fe4> Fe1> Fe5> Fe2> ***,Fe4/MAO displayed the highest activity of 1.94×10^(7) g_(PE)·mol_(Fe)^(-1)·h^(-1) of the study with only a modest loss in performance at 90℃.Generally,the resulting polyethylenes were highly linear(T_(m) range:122-132℃),narrowly disperse and of low molecular weight(M_(w) range:6.73-46.04kg·mol^(-1)),with the most sterically hindered Fe3 forming the highest molecular weight polymer of the ***-group analysis by ^(1)H-and ^(13)CnMR spectroscopy revealed saturated alkyl(n-propyl and i-propyl) and unsaturated vinyl chain ends indicative of the role of both β-H elimination and chain transfer to aluminum as termination *** comparison with previou sly reported iron precatalysts with similar tridentate ligand skeletons,it is evident that the introduction of a large benzhydryl group in combination with a fluorine as the ortho-substituents of one n-aryl group has the effect of enhancing thermal stability of the iron polymerization catalyst whilst maintaining appreciable polymer molecular weight.

关键词： Iron catalyst Ethylene polymerization Linear polyethylene Fluoride effect Thermal stability

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Impact damage testing based on high-speed continuous water jet aircraft coatings

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Chinese Journal of Aeronautics 2024年第10期37卷 249-264页

作者： Minggong SHA Ying SUn Yutong LI Yiming LIU gregory FEDOTEnKOV Lev RABInSKIY Arseniy BABAYTSEV Yulong LI School of Civil Aviation Northwestern Polytechnical UniversityXi’an 710072China Joint International Research Laboratory of Impact Dynamics and Engineering Application Xi’an 710072China Shaanxi Impact Dynamics and Engineering Application Laboratory Xi’an 710072China nPU Yangzi River Delta Research Institute Suzhou 215400China Moscow Aviation Institute(national Research University) Moscow 125993Russia

When an aircraft passes through a rainy area at high speed,the coating on the front edge of the fuselage will be continuously eroded by raindrops,causing the coating to wear,crack or even peel *** paper uses carbon fiber T300 material as the base material,and at the different impact speeds and impact numbers,water cutting equipment was used to simulate the erosion of the coating caused by the continuous impact of water *** damage morphology of samples at different damage stages was observed by digital microscope and Scanning Electron Microscope(SEM),and the damage evolution curve was established to analyze and reveal the damage behavior and damage mechanism of rain *** results show that the degree of damage experienced an increasing trend with the increase of impact numbers and speed,until circular peel damage was formed;no damage occurred during the incubation period,and the curvature of the damage evolution curve increased significantly after the expansion period and eventually showed a stable expansion *** mechanical properties of the coating material were the main influencing factors of its rain corrosion ***,the axially symmetric unsteady contact problem of droplets impacting the surface of a solid deformable body was *** the contact area was determined based on the iterative algorithm boundary positioning method.A mathematical model and closed mathematical formula describing the unsteady interaction between a droplet and a solid deformable obstacle were proposed.

关键词： Rain erosion damage Liquid-solid impact Multiple jets Composite materials Impact dynamics

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A remarkable class of elliptic surfaces of amplitude 1 in weighted projective spaces

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Science China Mathematics 2024年

作者： gregory Pearlstein Chris Peters Wim nijgh Department of Mathematics University of Pisa Department of Mathematics & Computer Science Technical University of Eindhoven Department of Mathematics University of Leiden

Surfaces of amplitude 1 in the ordinary projective space are of the general type, but this need not be the case in weighted projective spaces. Indeed, there are 4 classes of quasi-smooth weighted hypersurfaces in P（1, 2, a, b） of amplitude 1 with an elliptic pencil cut out by hyperplanes. Their moduli spaces are constructed,and the monodromy of their universal families is determined as well as their period maps which turn out to be generally immersive. For those that are not, a mixed Torelli theorem holds. We added an application to certain compactifications of moduli spaces of surfaces of the general type with K2= 1, pg= 2 and q = 0 as a follow up of Gallardo et al.（2022）, as well as detailed SageMath-calculations. The appendix written by Wim nijgh shows that the general member of the types 1 and 2 elliptic family has a “trivial” Picard lattice, i.e., is spanned by fiber components and a multisection.

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