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High Voltage 2021年第1期6卷 82-94页

作者： Johnatan M.Rodríguez‐serna ricardo albarracín‐sánchez Department of Electrical and Electronic Engineering Automatic Controland Applied PhysicsSchool of Industrial Design and Engineering(ETSIDI)Universidad Politécnica de Madrid(UPM)MadridSpain Department of Electrical Engineering Universidad de AntioquiaMedellínColombia

Electrical trees are defects originated and driven by partial discharges(PD)activity and this is the reason why their modelling and simulation are fundamental for the ageing mechanisms comprehension and diagnosis analyses of insulation systems compound by solid *** study presents a brief review of the different models implemented to simulate PD in electrical trees inside solid *** addition,an improved deterministic model as well as a stochastic model are presented,which allow predicting adequately the PD pulses distribution,in magnitudes and phase,for non‐conducting electrical trees of different shape and *** case studies were simulated and their results exhibit good agreement when compared with measurements presented in the *** is concluded that the main parameters that state the PD behaviour in trees are the inception and extinction voltage mag-nitudes,including their probability distributions,and the tree *** models can be used for prognosis analysis based on on‐line measurements.

关键词： solid conducting electrical

Finite-element-analysis models for numerical simulation of partial discharges in spherical cavities within solid dielectrics:a review and a novel method

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High Voltage 2020年第5期5卷 556-568页

作者： Johnatan M.Rodríguez-serna ricardo albarracín-sánchez Abdullahi A.Mas'ud Department of Electrical and Electronic Engineering Automatic Controland Applied PhysicsSchool of Industrial Design and Engineering(ETSIDI)Universidad Politécnica de Madrid(UPM)Ronda de Valencia 328012MadridSpain 2Department of Electrical EngineeringUniversidad de AntioquiaCalle 67 No.53-108MedellínColombia 3Department of Electrical and Electronic Engineering TechnologyJubail Industrial College31961JubailSaudi Arabia

During the last two decades,partial discharges(PDs)modelling methods have been used as a complement of insulation diagnosis systems of electrical ***-element-analysis models for simulating PDs in cavities within solid dielectric materials are reviewed and a novel model is presented,which combines the main advantages of electrostatic and electric current *** theoretical background is presented and some limitations and restrictions are discussed.A case of study was implemented for three different ageing conditions and simulation results exhibit good agreement with reported values by other authors in the *** analysis of variations of PD behaviour with ageing as a function of temperature and pressure is briefly *** is concluded that more research is needed to include physical and chemical interactions on the void surface and that the cavity surface conductivity plays a fundamental role in the PD simulations at advanced ageing conditions.

关键词： element analysis solid

Propagation and localisation of partial discharge in transformer bushing based on ultra-high frequency technique

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High Voltage 2021年第4期6卷 684-692页

作者： Jun Jiang Judong Chen Jiansheng Li Xiaoping Yang ricardo albarracín-sánchez Prem Ranjan Chaohai Zhang Jiangsu Key Laboratory of new Energy Generation and Power Conversion Nanjing University of Aeronautics and AstronauticsNanjingChina Department of Electrical&Electronic Engineering School of EngineeringThe University of ManchesterManchesterUK state Grid Jiangsu Electric Power Co.Ltd.Research Institute NanjingChina state Grid Jiangsu Electric Power Co.Ltd. NanjingChina Department of Electrical Electronic and Automation Engineering and Applied PhysicsUniversidad Politécnica de Madrid(UPM)MadridSpain

As an essential component of power transformers,the detection and diagnosis of incipient partial discharge(PD)activities of bushings are of great significance.A 35-kV oil-impregnated paper(OIP)bushing is *** bushing is modelled by coaxial theory and electromagnetic(EM)*** the paths of PD-induced ultra-high frequency(UHF)signal propagating in the bushing are OIPs and oil gap,small attenuation during signal propagation is *** OIP is composed of het-erogeneous media compared with pure oil,there will be relatively less UHF signal leakage from OIPs,whereas more leakage from the oil *** leakage provides the possibility of non-contact detection outside the bushing by UHF *** mea-surements with UHF method are carried out on the ***,the minimum energy method is used to extract time-difference-of-arrival(TDOA),and Chan al-gorithm is adopted to locate points of UHF signal *** accuracy locating with a small error of 15 cm has been *** contactless UHF method-based tests have demonstrated the effectiveness of online monitoring and locating of bushing PD.

关键词： locating high outside

Assessing the energy saving potential of using adaptive setpoint temperatures:The case study of a regional adaptive comfort model for Brazil in both the present and the future

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Building simulation 2024年第3期17卷 459-482页

作者： Daniel sánchez-García David Bienvenido-Huertas Carlos Rubio-Bellido ricardo Forgiarini Rupp Department of Electrical Engineering University Carlos III of MadridMadridSpain Department of Building simulation ZEROCEM SLSevilleSpain Department of Building Constructions University of GranadaGranadaSpain Department of Building Constructions II University of SevilleSevilleSpain section of Design for sustainability Department of Civil and Mechanical EngineeringTechnical University of DenmarkKgs.LyngbyDenmark

It has been found in recent years that using setpoint temperatures based on adaptive thermal comfort models is a successful method of energy *** studies using adaptive setpoint temperatures incorporate international models from AsHRAE standard 55 and *** study,however,has instead considered a regional Brazilian adaptive comfort *** study investigates the energy demand arising from the use of a local Brazilian comfort model in order to assess the energy implications from the use of the worldwide AsHRAE standard 55 adaptive model and various fixed setpoint *** of Brazil’s climate zones,full air-conditioning,mixed-mode building operating modes,present-day climate change scenarios,and future scenarios—specifically Representative Concentration Pathways(RCP)2.6,4.5,and 8.5 for the years 2050 and 2100—have all been taken into account in building energy *** use of adaptive setpoint temperatures based on the Brazilian local model considering mixed-mode has been found to significantly reduce energy consumption when compared to static setpoint temperatures(average energy-saving values ranging from 52%to 58%)and the AsHRAE 55 adaptive model(average values ranging from 15%to 21%).Considering climate change and the mixed-mode Brazilian model,the overall energy demand for the three groups of climatic zones(annual average outdoor temperatures≤21℃,>21 and≤25℃and>25℃)ranged between 2%decrease and 5%increase,4%and 27%increase,and 13%and 45%increase,*** is concluded as a consequence that setting setpoint temperatures based on the Brazilian local adaptive comfort model is a very efficient energy-saving method.

关键词： adaptive thermal comfort building energy simulation energy efficiency climate change adaptive setpoint temperatures local comfort mode

Morphometry and Mineral Content in the seeds and soil of Two species of Argemone L.(Papaveraceae)in the Central Part of the Chihuahuan Desert

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Phyton-International Journal of Experimental Botany 2024年第2期93卷 371-386页

作者： Perla Patricia Ochoa-García Jaime sánchez-salas ricardo Trejo-Calzada Jesús JosafathQuezada-Rivera Fabián García-González Unidad Regional Universitaria de ZonasÁridas BermejilloUniversidad Autónoma ChapingoDurango35230México Facultad de Ciencias Biológicas Universidad Juárez del Estado de DurangoGómez PalacioDurango35010México

The genus Argemone L.(Papaveraceae)is found widely distributed in Mexico’s Chihuahuan Desert(CD).some species of this genus are of phytochemical or ethnobotanical *** are inedible plants considered as *** date they have not been broadly studied;thus,their ecology is,to our knowledge,*** present work was centered around carrying out a morphometric analysis and the determination of minerals in the soil and seeds of the wild populations of Argemone at sites belonging to two ecoregions of the CD in *** April 2021 and April 2022,seeds of Argemone spp.,and soil samples were collected at 10 sites of the *** seeds were selected under a randomized design,and weight,length,diameter,thickness,buoyancy,and mineral content were *** soil samples were obtained under the Mexican regulation nOM-021-RECnAT-2000,and determinations of mineral content,electrical conductivity,apparent density,and soluble anions were *** information obtained was grouped by variable,species,and place of *** statistical tests consisted of an AnOVA,Tukey means tests considering p≤0.05,and a Principal Components *** pleiacantha exhibited differences in terms of weight(F=54.79,p=0.001),length(F=90.83,p=0.001),thickness(F=104.89,p=0.001),and diameter(F=155.82,p=0.001),and the differences in Argemone mexicana were in weight(F=46.71,p=0.001),thickness(F=187.49,p=0.001),length(F=191.56,p=0.001),and diameter(F=215.83,p=0.001).The evaluated seeds reached their maximal imbibition velocity at 24 h of *** content of the micro-and macro-nutrients analyzed in the seeds and soil suggest a tight relation with the morphometric characteristics of the seeds.

关键词： Micronutrients agricultural area semiarid zone ecoregion buoyancy

Influence of biomass burning on ozone levels in the Megalopolis of Central Mexico during the COVID-19 lockdown

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Journal of Environmental sciences 2024年第9期143卷 99-115页

作者： Victor Almanza Luis Gerardo Ruiz-suárez ricardo Torres-Jardón Agustín García-Reynoso Iván Y.Hernández-Paniagua Institute for Atmospheric sciences and Climate Change National Autonomous University of MexicoCoyoacan 04510Mexico CityMexico

The massive reductions in anthropogenic emissions resulting from the COVID-19 lockdown provided a unique opportunity to evaluate the effect of mitigation measures aiming to abate air *** Mexico,the total lockdown period took place during the dry-hot season when biomass burning activity is ***,we investigate the role of biomass burning emissions on regional ozone levels in the Megalopolis of Central *** studied period covers the lockdown phases 2 and 3,and the first month of the new *** applied a factor separation technique and process analysis to estimate the pure and synergistic contributions of emission reductions under lockdown and that from biomass burning to daily ozone maximum concentrations in 7 metropolitan areas of different states in the *** results revealed that biomass burning plumes likely masked the effect of massive reductions from mobile emissions,impacted the PBL development during phase 3 and favored transition and mixed nO_(x)-limited and VOC-limited regional *** contributed to increased ozone production in the middle to lower PBL by changing the regional background levels which potentially could bias high ozone production efficiency *** the Megalopolis contribution to economic and societal development at national scale,our study suggests that ozone mitigation measures during the dry-hot season targeting mainly mobile emissions will likely be offset by biomass burning plumes.A regional and synergic policy aiming to control biomass burning would help to reduce the occurrence of high ozone levels in Central Mexico with the co-benefit of tackling short-lived climate pollutants.

关键词： COVID-19 Mexico Megalopolis Ozone Factor separation Process Analysis

Comprehensive Euler/Lagrange modelling including particle erosion for confined gas-solid flows

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Particuology 2024年第1期84卷 209-235页

作者： Guiherme A.novelletto ricardo Martin sommerfeld Multiphase Flow systems Institute of Process EngineeringOtto-von-Guericke-University MagdeburgHoher Weg 7b06120Halle(Saale)Germany

The present research aims to assess the capability of a comprehensive Euler/Lagrange approach for predicting gas-solid flows and the associated solid particle *** open-source code OpenFOAM®4.1 was used to carry out the numerical simulations,where the standard Lagrangian libraries were substantially extended to account for all necessary *** are tracked considering both translational and rotational motion as well as all relevant forces,such as gravity/buoyancy,drag and transverse lift due to shear and particle *** tracking time step was dynamically adapted ac-cording to the locally relevant time scales,which drastically reduces computational *** approaches are adopted to model particle turbulent dispersion,particle collisions with rough walls and particle-particle *** solid particle erosion models,available in the literature,were considered to estimate pipe bend *** study cases are provided to validate the adopted nu-merical approach and erosion models *** first case intends to evaluate the ability of the extended CFD code to predict the behaviour of gas-solid flows in pneumatic conveying *** goal is achieved by comparing the numerical results with the experimental data obtained by Huber(1997)and Huber and sommerfeld(1994,1998)in a pneumatic conveying ***,the importance of considering inter-particle collisions and surface roughness for predicting particle velocity,mass flux and mean diameter distributions in gas-solid flows is *** second and third case intend to evaluate the ability of the erosion models in estimating bend erosion in diluted gas-solid *** erosion data obtained experimentally by Mazumder et al.(2008)and solnordal et al.(2015)in very dilut pneumatic conveying systems is used for validating the numerical results,neglecting now inter-particle collisions and two-way *** a comprehensive analysis of the different influential properti

关键词： Pneumatic conveying Pipe bend numerical calculation(CFD) Euler/Lagrange approach Erosion models Wall roughness

Habitat and food preferences of European rabbits in core and edge populations along the invasion front PatagoniaMonte,Argentina

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Current Zoology 2024年第3期70卷 310-319页

作者： sabrina Yasmin Bobadilla María A.Dacar Fabián M.Jaksic ricardo A.Ojeda María Fernanda Cuevas Ecología de Mamíferos de Tierras secas IADIZACCT-Mendoza CONICETAv.Ruiz Leal s/nParque General San MartínMendoza 5500MendozaArgentina Laboratorio de Filogeografía Taxonomía Integrativa y Ecología(LFTIE)IADIZACCT-Mendoza CONICETAv.Ruiz Leal s/nParque General San MartínMendoza 5500MendozaArgentina Center of Applied Ecology and sustainability(CAPEs) Pontifcia Universidad Católica de ChileAv.Libertador Bernardo O'Higgins 340Santiago 8320000Región MetropolitanaChile

The European rabbit Oryctolagus cuniculus is an exotic herbivorous mammal undergoing an active phase of geographical expansion in the arid ecosystems of *** Adaptive Flexibility Hypothesis states that populations at the range edge(new populations)will exhibit greater fexibility in the use of resources compared with populations located in the range core(older populations).The objective of this work was to compare the rabbit’s use of spatial and trophic resources in relation to the establishment time of their *** sampling was carried out for 2 years(2017 and 2018)in sites with different establishment times for rabbit *** sampling stratifed by type of habitat was applied using 115 fxed strip transects of 1,000 m^(2) laid out across the study *** rabbit signs were recorded in each transect,and environmental and anthropic variables were *** results show that the individuals from the range edge are more selective in the use of habitat than those from the range *** the microhabitat level,we observed a pattern in the particular components of habitat use by rabbits mainly linked to food availability and proximity to *** a trophic perspective,rabbits could show fexible adjustment to novel conditions and environments in the range *** variability in resource use by the European rabbit confrms its ecological fexibility,pivotal for their advance toward new environments in Argentina.

关键词： Arid ecosystems invasive species novel environments range invasion spatial use trophic use

Testicular prostheses-impact on quality of life and sexual function

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Asian Journal of Andrology 2024年第2期26卷 160-164页

作者： Ana sofia Araujo sara Anacleto ricardo Rodrigues Catarina Tinoco Andreia Cardoso Carlos Oliveira ricardo Leao Department of Urology Braga's HospitalBraga 4710Portugal Faculty of Medicine Coimbra UniversityCoimbra 3000Portugal

Orchiectomy is the recommended treatment for many testicular ***,testicular prosthesis placement is not always performed for different *** this study,we aimed to evaluate patients'opinions and the impact on sexual function and quality of *** retrospective observational single-center study included patients who underwent orchiectomy between January 2014 and December 2020 at the Department of Urology,Braga's Hospital(Braga,Portugal),where testicular implants were always available and the decision to undergo the procedure was made fully independent of *** completed four questionnaires that assessed demographic data,satisfaction,self-esteem,and sexual *** the 96 patients who underwent orchidectomy,59 replied to the questionnaires,and of these patients,86.4%decided to undergo silicone-based testicular prostheses *** remaining 13.6%refused the implant based on concerns about complications(37.5%),because they felt that it was unnecessary(37.5%),or because it was not offered by the doctor(25.0%).Overall,96.1%of these patients were satisfied with the implant;however,25.5%classified it as"too firm".no statistically significant differences were found in sexual function(all P>0.05).However,it can be observed that there are more patients with prostheses presenting normal sexual activity compared to patients without prostheses(74.0%vs 50.0%),and none of them reported severe erectile dysfunction(0 vs 16.7%).Regarding self-esteem,both patients with and without prostheses present very similar average scores with no statistically significant *** present study highlights the highest level of satisfaction among patients who received testicular *** prostheses implantation is a safe procedure that does not hamper sexual function after orchiectomy.

关键词： orchiectomy patient satisfaction quality of life sexual dysfunction sexual health testicular prostheses

new pharmacological tools:the use of diterpenes to promote adult hippocampal neurogenesis

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neural Regeneration Research 2024年第8期19卷 1629-1630页

作者： ricardo Gomez-Oliva Pedro nunez-Abades Carmen Castro Department of Biomedicine Biotechnology and Public HealthDivision of PhysiologyUniversity of CadizCadizSpain Biomedical Research and Innovation Institute of Cadiz(IniBICA) CadizSpain Department of Physiology University of SevilleSevilleSpain

Tissue regeneration maintains homeostasis and preserves the functional features of each ***,not all tissues show a strong repairing *** is the case of the central nervous *** is now well established that the generation of new functional neurons from stem cells in the adult brain occurs in specific regions of the brain of different species such as rodents,birds,primates,and humans(Eriksson et al.,1998).

关键词： capacity maintain preserve