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nonlinear dynamics of the reversed shear Alfvén eigenmode in burning plasmas

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Plasma Science and Technology 2024年第5期26卷 1-16页

作者：王涛魏士朝 sergio BRIGUGLIO Gregorio VLAD Fulvio ZOnCA 仇志勇 Institute for Fusion Theory and Simulation and School of Physics Zhejiang UniversityHangzhou 310027People’s Republic of China Center for nonlinear Plasma Science ENEA C.R.FrascatiFrascati 00044Italy Fusion and nuclear Safety Department ENEA C.R.FrascatiFrascati 00044Italy

In a tokamak fusion reactor operated at steady state,the equilibrium magnetic field is likely to have reversed shear in the core region,as the noninductive bootstrap current profile generally peaks *** reversed shear Alfvén eigenmode(RSAE)as a unique branch of the shear Alfvén wave in this equilibrium,can exist with a broad spectrum in wavenumber and frequency,and be resonantly driven unstable by energetic particles(EP).After briefly discussing the RSAE linear properties in burning plasma condition,we review several key topics of the nonlinear dynamics for the RSAE through both wave-EP resonance and wave-wave coupling channels,and illustrate their potentially important role in reactor-scale fusion *** means of simplified hybrid MHD-kinetic simulations,the RSAEs are shown to have typically broad phase space resonance structure with both circulating and trapped EP,as results of weak/vanishing magnetic shear and relatively low *** the route of wave-EP nonlinearity,the dominant saturation mechanism is mainly due to the transported resonant EP radially decoupling with the localized RSAE mode structure,and the resultant EP transport generally has a convective *** saturated RSAEs also undergo various nonlinear couplings with other collective *** typical routes as parametric decay and modulational instability are studied using nonlinear gyrokinetic theory,and applied to the scenario of spontaneous excitation by a finite amplitude pump *** RSAEs could naturally couple and induce the spectral energy cascade into a low frequency Alfvénic mode,which may effectively transfer the EP energy to fuel ions via collisionless Landau ***,zero frequency zonal field structure could be spontaneously excited by modulation of the pump RSAE envelope,and may also lead to saturation of the pump RSAE by both scattering into stable domain and local distortion of the continuum structure.

关键词： reversed shear Alfvén eigenmode energetic particle nonlinear gyrokinetic theory saturation burning plasma

Fast prediction of rain erosion in wind turbine blades using a data-based computational tool

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Journal of Hydrodynamics 2024年第3期36卷 504-518页

作者： Juan M.Gimenez sergio R.Idelsohn Eugenio Oñate Centre Internacional de Mètodes numèrics en Enginyeria(CIMnE) Edifici C1 Campus Nord UPC C/Gran CapitàS/NBarcelonaSpain

Wind turbines(WTs)face a high risk of failure due to environmental factors like erosion,particularly in high-precipitation areas and offshore *** this paper we introduce a novel computational tool for the fast prediction of rain erosion damage on WT blades that is useful in operation and maintenance decision making *** approach is as follows:Pseudo-Direct numerical Simulation(P-DnS)simulations of the droplet-laden flow around the blade section profile are employed to build a high-fidelity data set of impact statistics for potential operating *** this database as training data,a machine learning-based surrogate model provides the feature of the impact pattern over the 2-D section for given wind and rain *** this information,a fatigue-based model estimates the remaining lifetime and erosion damage for both homogeneous and coating-substrate blade *** prediction is done by quantifying the accumulated droplet impact energy and evaluating operative conditions over time periods for which the weather at the installation site is *** this work,we describe the modules that compose the prediction method,namely the database creation,the training of the surrogate model and their coupling to build the prediction ***,the method is applied to predict the remaining lifetime and erosion damage to the blade sections of a reference *** evaluate the reliability of the tool,several site locations(offshore,coastal,and inland),the coating material and the coating thickness of the blade are *** few minutes we are able to estimate erosion after many years of *** results are in good agreement with field observations,showing the promise of the new rain erosion prediction approach.

关键词： Wind turbine blades leading edge erosion fatigue Pseudo-Direct numerical Simulation(P-DnS) machine learning eblader

Semiosic Translation:a Bayesian-heuristic theory of translation and translating

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Language and Semiotic Studies 2024年第2期10卷 167-202页

作者： sergio Torres-Martínez Universidad de Antioquia Cll.67#53–108MedellínAntioquiaColombia

In the context of Semiosic Translation,two elements are essential for a translation to emerge:the body–brain–context interface(extended mind)and the sign systems making up a translation *** this paper,I explain how a renewed view of the body as a Bayesian-heuristic Semiotic Prior helps to understand in a more holistic manner the motivations and agentive character of translation,defined herein as a phenomenological grasp of the *** to the present proposal is the idea that bodily self-stabilization(homeostasis)and brain-driven correction(allostasis)provide translator-agents with maps of action upon the world that are semiotic in *** this occurs thanks to information weighing(Bayesian)and cue-driven(heuristic)types of inference whereby exteroceptive(exogenous)and interoceptive(inner-body)signals converge to create a sense of bodily awareness responsible for the construction of the symbolic persona(the translator-agent).

关键词： embodiment Bayesian semiosis heuristic semiosis semiotics Semiosic Translation translator-agents

A new approach to pedestal differentiation for soil loss estimation-a case study from a burnt area in north-central Portugal

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Journal of Forestry Research 2024年第3期35卷 45-54页

作者： Frank G.A.Verheijen Martinho A.S.Martins sergio A.Prats Jan J.Keizer Centre for Environmental and Marine Studies(CESAM) Department Environment and PlanningUniversity of Aveiro3810-193 AveiroPortugal Mediterranean Institute for Agriculture Environment and Development(MED-CHANGE)Institute for Advanced Studies and ResearchUniversity of EvoraPolo da MitraAp.947006-554 EvoraPortugal GeoBiociencias Geotecnologias E Geoengenharias(GEOBIOTEC)Department Environment and PlanningUniversity of Aveiro3810-193 AveiroPortugal

Soil pedestals have long been used as qualitative indicators of soil splash *** rangelands,plant-capped pedestals,generally grass tussocks,have also been used to quantitatively estimate soil loss since the first half of the twentieth *** agricultural lands,forests,and bad-lands,stone-capped pedestals have been used as qualitative and semi-quantitative indicators of active,'extreme'*** work has been reported on using capstone pedestal data for quantifying soil *** postulate that three distinct capstone pedestal types may be present in any given location and that a detailed analysis of a pedestal height histogram may be used to recognize their *** analysis can subsequently inform if soil loss can be reliably estimated and if so,which of the existing methods using pedestal height data will provide more accurate *** three proposed capstone pedestal types are:(1)neo-pedestals formed underneath surface stones exposed by(partial)removal of the soil surface cover;(2)endo-pedestals formed underneath stones that were buried in the soil but have been exposed by erosion;and(3)phoenix-pedestals formed underneath stones from collapsed *** the pedestal height histogram of any given location,a skew to smaller heights may indicate the existence of endo-and/or phoenix-pedestals,which may be revealed as a bi-(or tri)modal distribution when using a smaller bin *** concept was applied to a case study where soil loss had been monitored for control plots and mulched plots during a 5-year period following wildfire in a eucalypt *** measured pedestal heights and used methods to quantitatively assess soil loss from soil pedestal data in the available *** pedestal data at the end of the 5-year period under or overestimated soil loss in the control treatment,with results ranging from 60 to 115%of measured soil loss,depending on the *** is postulated that phoenix-and endo-pedestals may be a driving fact

关键词： Soil pedestals Mulch Wildfire Soil erosion Char

Reproductive patterns in Araucaria araucana forests in the Andean range, Chile

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Ecological Processes 2024年第01期13卷 252-261页

作者： sergio Donoso Karen Pe?a-Rojas Claudia Espinoza Carolain Badaracco Rómulo Santelices-Moya Antonio Cabrera-Ariza Mediterranean Forests Laboratory Faculty of Forestry and Nature Conservation Centro Secano Faculty of Agricultural and Forestry Sciences Universidad Católica del Maule Maule Advanced Studies Research Center Vice-Rector's Office for Research and Postgraduate Studies Catholic University of Maule

Background Araucaria araucana is a mast species that presents a high variability in annual cone production. Researchers have recorded synchronization events in cone production in different populations, which allows the seed production to be concentrated, reducing the percentage of seeds consumed by different animal *** We sampled three populations located in the Andes Mountains, Araucanía Region, Chile. In 2004 we began the collection of data on cone production, for which we installed permanent plots（1200 m2each） at each location. We identified and labeled each female tree in each plot to monitor its cone production. In 2012 we selected a total of 30 trees near the plots to evaluate the number of seeds per cone. In each February from 2012 to 2014 we selected two mature cones and covered them with a porous mesh for subsequent collection and storage in March. At the beginning of June, we counted and weighed the seeds, determining the average weight, the number of seeds per cone, the germination capacity（GC）, and the germination speed（GS）.Results Cone production was synchronous across the three locations. We observed significant differences among the locations and years evaluated. The cones had fewer seeds in 2013（high production） compared to those in 2012（low production）, but their weights were similar. In 2014 the cones produced smaller seeds in fewer quantities. The difference between the years 2013 and 2014 resulted from the high-energy expenditure in 2013. Regarding GC and GS, there were significant differences among the three locations（GC: F = 45.41, p n *** Both GC and GS are related to seed weight but not to the number of cones produced in a given year. These annual fluctuations in seed production are determining factors in the population dynamics of forest species. Our results allow a better understanding of the reproductive phenology of A. araucana and could hel

关键词： Seed weight Germination potential Masting species Sustainable use Dioecious species

Free-electron crystals for enhanced X-ray radiation

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Light(Science & Applications) 2024年第7期13卷 1299-1309页

作者： Lee Wei Wesley Wong Xihang Shi Aviv Karnieli Jeremy Lim Suraj Kumar sergio Carbajo Ido Kaminer Liang Jie Wong School of Electrical and Electronic Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore. Solid State Institute and Faculty of Electrical and Computer Engineering Technion–Israel Institute of TechnologyHaifa 3200003Israel. School of Electrical Engineering Fleischman Faculty of EngineeringTel Aviv UniversityTel Aviv 69978Israel Department of Applied Physics Stanford UniversityStanfordCA 94305USA. Science Mathematics and TechnologySingapore University of Technology and Design8 Somapah RoadSingapore 487372Singapore. Electrical and Computer Engineering Department UCLA420 WestwoodLos AngelesCA 90095USA. Physics and Astronomy Department UCLA475 Portola PlazaLos AngelesCA 90095USA. SLAC national Accelerator Laboratory Stanford University2575 Sand Hill RoadMenlo ParkCA 94025USA

Bremsstrahlung—the spontaneous emission of broadband radiation from free electrons that are deflected by atomic nuclei—contributes to the majority of X-rays emitted from X-ray tubes and used in applications ranging from medical imaging to semiconductor chip ***,we show that the bremsstrahlung intensity can be enhanced significantly—by more than three orders of magnitude—through shaping the electron wavefunction to periodically overlap with atoms in crystalline ***,we show how to shape the bremsstrahlung X-ray emission pattern into arbitrary angular emission profiles for purposes such as unidirectionality and ***,we find that these enhancements and shaped emission profiles cannot be attributed solely to the spatial overlap between the electron probability distribution and the atomic centers,as predicted by the paraxial and nonrecoil theory for free electron light *** work highlights an unprecedented regime of free electron light emission where electron waveshaping provides multi-dimensional control over practical radiation processes like *** results pave the way towards greater versatility in table-top X-ray sources and improved fundamental understanding of quantum electron-light interactions.

关键词： overlap attributed arbitrary

A new look at the first dinosaur discovered in Antarctica:reappraisal of Antarctopelta oliveroi(Ankylosauria:Parankylosauria)

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Advances in Polar Science 2024年第1期35卷 78-107页

作者： sergio SOTO ACUÑA Alexander OVARGAS Jonatan KALUZA Red Paleontológica U-Chile Departamento de BiologíaFacultad de CienciasUniversidad de ChileÑuñoa 7800003Chile Escuela de Geología Facultad de CienciasIngeniería y TecnologíaUniversidad MayorProvidenciaSantiago 7500994Chile Fundación de Historia natural Félix de Azara Universidad MaimónidesBuenos Aires C1405Argentina Consejo nacional de Investigaciones Científicas y Técnicas(COnICET) Buenos Aires C1425FQBArgentina

The first dinosaur discovered in the Antarctic continent was the ankylosaur Antarctopelta oliveroi in the ***,since then several hypotheses of phylogenetical relationships have been proposed because these have been depended on how the skeletal remains have been *** main obstacle for clarifying its phylogenetic position is that many portions of the skeleton remain unknown,in addition to the presence of unknown characters in typical *** an ankylosaurid,nodosaurid,or even a chimaera,a recent proposal based on mostly complete material of a new ankylosaur from Chilean Patagonia provided support for a novel phylogenetic hypothesis:Antarctopelta and other southern ankylosaurs are an early branching clade,the Parankylosauria,whose origin probably dates to the Late *** the light of this new view,a redescription of the available skeletal remains is provided together with a new reconstruction of the first Antarctic dinosaur known to the science community.

关键词： Antarctic Peninsula Biogeographic Weddellian Province Parankylosauria Antarctopelta

Stress tensors and quantification of fracture patterns to analyze connectivity and potential fluid flow in a mesa landform of the northern Andes

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Journal of Mountain Science 2024年第1期21卷 271-291页

作者： GARCÍA-ARIAS sergio VELAnDIA Francisco ALVAREZ Angélica SAnABRIA-GÓMEZ JoséD TARAZOnA Yessenia VARGAS María Camila Escuela de Geología Universidad Industrial de SantanderCra.27 Calle 9BucaramangaColombia Escuela de Física Universidad Industrial de SantanderCra.27 Calle 9BucaramangaColombia

This work applies stress tensors inversions and quantification of fracture patterns along the Mesa de Los Santos, in the Eastern Cordillera of Colombia, to better understand the potential fluid flow. It thus contributes to the conceptual hydrogeological model. The area was subdivided into three blocks, separated by the nW Potreros and the Los Santos faults, having minor inner faults of different orientations. This separation facilitates the analysis of the fractures measured in the field, which in general show high dip angles and a conjugate geometry in the northern block, tension fractures(Mode I) in the central block, and a random distribution in the southwestern block. WinTensor treatment of slickensides yielded a maximum horizontal stress(SHmax) of 111o, which coincides with the WnW-ESE tensor observed from the conjugate and tension joints. We then used Frac Pa Q to generate interpolation maps of fracture intensity and density. The maps show the highest values in the central block and the lowest in the northern block,where the precipitation is higher, causing intensive rock weathering and homogenization of the fracture planes. Although the highest values of connectivity by line are found to the south of the mesa, we suggest the possibility of greater flow from the recharge zone(nE) along bedding planes and open nW-SE fractures.

关键词： Mesa de Los Santos Colombia Win-Tensor FracPaQ Strike-slip faults Fractured aquifers

Greening the Belt and Road Initiative: Evidence from emergy evaluation of China’s provincial trade with ASEAn countries

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Fundamental Research 2024年第2期4卷 379-393页

作者： Xu Tian Joseph Sarkis Wei Chen Yong Geng Haozhi Pan Zuoxi Liu sergio Ulgiati SJTU-UnIDO Joint Institute of Inclusive and Sustainable Industrial Development School of International and Public AffairsShanghai Jiao Tong UniversityShanghai 200030China Worcester Polytechnic Institute Worcester MA 01609-2280USA School of Geography and Environment Shandong Normal UniversityJinan 250358China School of International and Public Affairs Shanghai Jiao Tong UniversityShanghai 200030China Key Laboratory of Clean Energy of Liaoning School of Energy and EnvironmentShenyang Aerospace UniversityShenyang 110136China Department of Science and Technology Parthenope University of NapoliNaples 80143Italy School of Environment Beijing Normal UniversityBeijing 100875China

The Belt and Road Initiative(BRI)is a central policy within China’s regional development and foreign trade *** trade has typically depended on economic valuation of resources,while the embedded environmental value is rarely *** situation exists in most BRI trade *** address BRI environmental sustainability issues,we consider the role of pivotal Chinese provinces and their key trade partners(ASEAn countries)as an illustration for the environmental value of resource *** accounting is used as the valuation tool for a sample period of seventeen *** results include:(1)Emergy valuations show sustainability of sample provinces decreased over time;(2)ASEAn countries such as Indonesia,Malaysia,Singapore,Thailand,and Vietnam play significant resource roles for provincial economic systems;(3)Diverse trends in trade between pivotal provinces and ASEAn countries resulted in an unbalanced trade structure from *** implications are proposed to promote a more globally sustainable and fair trade using BRI as an established trade policy.

关键词： International trade Emergy Belt and road initiative Environmental sustainability Province