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Journal of modern Power Systems and Clean Energy 2021年第6期9卷 I0001-I0002页

作者： juan m.Gers A.P.Sakis meliopoulos GERS WestonFLUSA Georgia Tech AtlantaGA.USA

ELECTRICAL system characteristics are changing substantially as the penetration levels of renewable generation and in general converter interfaced generation resources(CIGRs)*** operation of these systems constitutes a challenge for the engineering in protection and control *** of the importance of CIGRs for the modern power systems lies in the integration of renewable energy sources into the conventional distribution system,reducing the environmental impact and emissions.

关键词： Smart Converter system

multi-EAP: Extended EAP for multi-estimate extraction for SmC-PHD filter

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Chinese Journal of Aeronautics 2017年第1期30卷 368-379页

作者： Li Tiancheng juan m.Corchado Sun Shudong Fan Hongqi School of Science University of Salamanca School of mechanical Engineering Northwestern Polytechnical University ATR Key Laboratory National University of Defense Technology

The ability to extract state-estimates for each target of a multi-target posterior, referred to as multi-estimate extraction（mEE）, is an essential requirement for a multi-target filter, whose key performance assessments are based on accuracy, computational efficiency and reliability. The probability hypothesis density（PHD） filter, implemented by the sequential monte Carlo approach,affords a computationally efficient solution to general multi-target filtering for a time-varying number of targets, but leaves no clue for optimal mEE. In this paper, new data association techniques are proposed to distinguish real measurements of targets from clutter, as well as to associate particles with measurements. The mEE problem is then formulated as a family of parallel singleestimate extraction problems, facilitating the use of the classic expected a posteriori（EAP） estimator, namely the multi-EAP（mEAP） estimator. The resulting mEAP estimator is free of iterative clustering computation, computes quickly and yields accurate and reliable estimates. Typical simulation scenarios are employed to demonstrate the superiority of the mEAP estimator over existing methods in terms of faster processing speed and better estimation accuracy.

关键词： Data association EAP estimator multi-target tracking PHD filter Particle filter

Diterpenes and the crosstalk with the arachidonic acid pathways, relevance in neurodegeneration

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Neural Regeneration Research 2019年第10期14卷 1705-1706页

作者： juan m. Zolezzi Nibaldo C. Inestrosa Centro de Envejecimiento y Regeneración (CARE UC) Department de Biología Celular y MolecularFacultad de Ciencias BiológicasPontificia Universidad Católica de ChileSantiagoChileCentro de Excelencia en Biomedicina de MagallanesUniversidad de MagallanesPunta ArenasChile Centre for Healthy Brain Ageing School of PsychiatryFaculty of MedicineUniversity of New South WalesSydneyAustralia

Dementia has emerged as one of the main threats to human health in the modern civilization. Increased aging of world population and unhealthy lifestyle habits have been identified as critical factors able to facilitate dementia establishment. In this context, according to the Alzheimer’s Research International, Alzheimer’s disease (AD) constitutes the primary cause of dementia worldwide and its numbers are expected to grow during the following years. Clinically, AD is characterized by the progressive decline in the cognitive performance as well as by an altered social behavior. Initially affecting the short-term memory, the long-term memory becomes compromised as the pathology progresses.

关键词： Dementia human health in the modern

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

Collapse of the endemic lizard Podarcis pityusensis on the island of Ibiza mediated by an invasive snake

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Current Zoology 2022年第3期68卷 295-303页

作者： Elba mONTES Fred KRAUS Brahim CHERGUI juan m.PLEGUEZUELOS Department of Zoology Faculty of Biological SciencesUniversity of Valenciac/Dr.Moliner50BurjassotE-46100 ValenciaSpain Department of Ecology and Evolutionary Biology University of MichiganAnn ArborMI 48109USA Laboratoire Ecologie SystématiqueConservation de la BiodiversitéFacultédes Sciences de TétouanUniversitéAbdelmalek EssaâdiBP 2121 El M’HannechTétouanMorocco Department of Zoology Faculty of SciencesGranada UniversityGranada E-18071Spain

The invasive snake Hemorrhois hippocrepis colonized the island of Ibiza(Balearic Islands)in 2003 as stowaways inside trunks of olive trees imported for *** has quickly spread since 2010,posing a threat to the island’s only remaining endemic vertebrate,the Ibiza wall lizard Podarcis *** map the yearly expansion rate of the snake and estimate via transect surveys how severely it affects the distribution and abundance of the endemic *** well,we surveyed 9 of 30 small lizard populations on islets surrounding Ibiza that have been isolated since the Last Glacial *** had invaded 49%of Ibiza’s land area by 2018,and censuses show a critical contrast in lizard abundance between areas with and without snakes;almost all censuses in areas without snakes show lizard presence whereas nearly all censuses in areas with *** lack lizard ***,at least one subspecies previously thriving on one of the offshore islets has become extinct,and there have been several snakes recorded swimming between Ibiza and the surrounding ***,lizard populations have been dramatically reduced or have vanished within the range of the snake,and our results quantitatively support upgrading this species’threat level for *** study can inform to programs to manage invasive snake populations and to conservation actions to recover the endemic lizard.

关键词： Balearic Islands conservation extinction Hemorrhois hippocrepis lizard census

Towards full repair of defects in reduced graphene oxide films by two-step graphitization

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Nano Research 2013年第3期6卷 216-233页

作者： Ruben Rozada juan I, Paredes Silvia Villar-Rodil Amelia marlinez-Alonso juan m. D. Tascon Instituto Nacional del Carbon INCAR-CSIC Apartado 73 33080 Oviedo Spain

The complete restoration of a perfect carbon lattice has been a central issue in the research on graphene derived from graphite oxide since this preparation route was first proposed several years ago, but such a goal has so far remained elusive. Here, we demonstrate that the highly defective structure of reduced graphene oxide sheets assembled into free-standing, paper-like films can be fully repaired by means of high temperature annealing （graphitization）. Characterization of the films by X-ray photoelectron and Raman spectroscopy, X-ray diffraction and scanning tunneling microscopy indicated that the main stages in the transformation of the films were （i） complete removal of oxygen functional groups and generation of atomic vacancies （up to 1,500 ~C）, and （ii） vacancy annihilation and coalescence of adjacent overlapping sheets to yield continuous polycrystalline layers （1,800-2,700 ~C） similar to those of highly oriented graphites. The prevailing type of defect in the polycrystalline layers were the grain boundaries separating neighboring domains, which were typically a few hundred nanometers in lateral size, exhibited long-range graphitic order and were virtually free of even atomic-sized defects. The electrical conductivity of the annealed films was as high as 577,000 S-m-1, which is by far the largest value reported to date for any material derived from graphene oxide, and strategies for further improvement without the need to resort to higher annealing temperatures are suggested. Overall, this work opens the prospect of truly achieving a complete restoration of the carbon lattice in graphene oxide materials.

关键词： graphene graphene oxide films annealing defect

A kinetic model for horizontal transfer and bacterial antibiotic resistance

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International Journal of Biomathematics 2017年第4期10卷 131-151页

作者： Damian A. Knopoff juan m. Sanchez Sanso Centro de Investigacion y Estudios de matemdtica CONICET -- FamAF Universidad Nacional de Cordoba Medina AUende s/n Cordoba 5000 Argentina Department of General Surgery Hospital misericordia Nuevo Siglo Cordoba 5000 Argentina

This paper presents a mathematical model for bacterial growth, mutations, horizontal transfer and development of antibiotic resistance. The model is based on the so-called kinetic theory for active particles that is able to capture the main complexity features of the system. Bacterial and immune cells are viewed as active particles whose microscopic state is described by a scalar variable. Particles interact among them and the temporal evolution of the system is described by a generalized distribution function over the microscopic state. The model is derived and tested in a couple of case studies in order to confirm its ability to describe one of the most fundamental problems of modern medicine, namely bacterial resistance to antibiotics.

关键词： Kinetic theory active particles antibiotic resistance horizontal gene transfer

multiscale Finite Elementmethods for Flows on Rough Surfaces

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Communications in Computational Physics 2013年第9期14卷 979-1000页

作者： Yalchin Efendiev juan Galvis m.Sebastian Pauletti Department of mathematics TAMUCollege StationTX 77843-3368USA Departamento de matematicas Universidad Nacional de ColombiaBogotaColombia

In this paper,we present the multiscale Finite Element method(msFEm)for problems on rough heterogeneous *** consider the diffusion equation on oscillatory *** objective is to represent small-scale features of the solution via multiscale basis functions described on a coarse *** problem arises in many applications where processes occur on surfaces or thin *** present a unified multiscale finite element framework that entails the use of transformations that map the reference surface to the deformed *** main ingredients of msFEm are(1)the construction of multiscale basis functions and(2)a global coupling of these basis *** the construction of multiscale basis functions,our approach uses the transformation of the reference surface to a deformed *** the deformed surface,multiscale basis functions are defined where reduced(1D)problems are solved along the edges of coarse-grid blocks to calculate nodalmultiscale basis ***,these basis functions are transformed back to the reference *** discuss the use of appropriate transformation operators that improve the accuracy of the *** method has an optimal convergence if the transformed surface is smooth and the image of the coarse partition in the reference configuration forms a quasiuniform *** this paper,we consider such transformations based on harmonic coordinates(following *** and ***[*** and Applied math.,LX(2007),pp.675-723])and discuss gridding issues in the reference *** results are presented where we compare the msFEm when two types of deformations are used formultiscale basis *** first deformation employs local information and the second deformation employs a global *** numerical results showthat one can improve the accuracy of the simulations when a global information is used.

关键词： multiscale finite elements on surfaces Laplace Beltrami resonance error harmonic maps

Carbonaceous residues from biomass gasification as catalysts for biodiesel production

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Journal of Natural Gas Chemistry 2012年第3期21卷 246-250页

作者： Rafael Luque Antonio Pineda juan C. Colmenares juan m. Campelo Antonio A. Romero juan Carlos Serrano-Ruiz Luisa F. Cabeza Jaime Cot-Gores Departamento de Quimica Organica Universidad de Cardoba Campus de Rabanales Edif icio Marie Curie E-14014 Cardoba Spain Universitat de Lleida GREA lnnovacio Concurrent Lleida Spain Universitat de Lleida GREA lnnovacio Concurrent Lleida Spain

Tars and alkali ashes from biomass gasification processes currently constitute one of the major problems in biomass valorisation, generating clogging of filters and issues related with the purity of syngas production. To date, these waste residues find no useful applications and they are generally disposed upon generation in the gasification process. A detailed analysis of these residues pointed out the presence of high quantities of Ca （〉30 wt%）. TG experiments indicated that a treatment under air at moderate temperatures （400-800 ~C） decomposed the majority of carbon species, while XRD indicated the presence of a crystalline CaO phase. CaO enriched valorized materials turned out to be good heterogeneous catalysts for biodiesel production from vegetable oils, providing moderate to good activities （50%-70% after 12 h） to fatty acid methyl esters in the transesterification of sunflower oil with methanol.

关键词： biomass gasification residues biodiesel catalyst calcium oxide

Collaborative learning via social computing

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Frontiers of Information Technology & Electronic Engineering 2019年第2期20卷 265-282页

作者： Ricardo S.ALONSO Javier PRIETO óscar GARCíA juan m.CORCHADO BISITE Research Group University of Salamanca

Educational innovation is a field that has been greatly enriched by using technology in its processes, resulting in a learning model where information comes from numerous sources and collaboration takes place among multiple students. One attractive challenge within educational innovation is the design of collaborative learning activities from the social computing point of view, where collaboration is not limited to student-to-student relationships, but includes student-to-machine interactions. At the same time, there is a great lack of tools that give support to the whole learning process and are not restricted to specific aspects of the educational task. In this paper, we present and evaluate context-aware framework for collaborative learning applications(CAFCLA) as a solution to these problems. CAFCLA is a flexible framework that covers the entire process of developing collaborative learning activities, taking advantage of contextual information and social interactions. Its application in the experimental case study of a collaborative WebQuest within a museum has shown that, among other benefits, the use of social computing improves the learning process, fosters collaboration, enhances relationships, and increases engagement.

关键词： Context-awareness Collaborative learning Social computing Virtual organizations Wireless sensor networks Real time location system