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Review of Networked Microgrid Protection:Architectures,Challenges,Solutions,and Future Trends

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CSee Journal of Power and energy Systems 2024年第2期10卷 448-467页

作者： Jorge de la Cruz Ying Wu John e.Candelo-Becerra juan C.Vasquez Josep M.Guerrero Center for Research on Microgrids(CROM) Department of Energy TechnologyAalborg University9220 AalborgDenmark Facultad de Minas Departamento de Energia Eléctrica y AutomaticaUniversidad Nacional de ColombiaSede MedellinCarrera 80 No.65-223RobledoMedellin 050041Colombia. Center for Research on Microgrids at UPC(UPC CROM) Department of Electronic EngineeringTechnical University of Catalonia(UPC)08019 Barcelona Spain ICReA Pg.Lluis Companys 2308010 BarcelonaSpain Center for Research on Microgrids at AAU(AAU CROM) AAU EnergyAalborg University(AAU)9220 Aalborg EastDenmark

Design and selection of advanced protection schemes have become essential for reliable and secure operation of networked *** protection schemes that allow correct operation of microgrids have been proposed for individual systems in different topologies and ***,protection schemes for networked microgrids are still in devel-opment,and further research is required to design and operate advanced protection in interconnected *** of these microgrids in different nodes with various intercon-nection technologies increases fault occurrence and complicates protection *** paper aims to point out challenges in developing protection for networked microgrids,potential solutions,and research areas that need to be addressed for their ***,this article presents a systematic analysis of different microgrid clusters proposed since 2016,including several architectures of networked microgrids,operation modes,components,and utilization of renewable sources,which have not been widely explored in previous review ***,the paper presents a discussion on protection systems currently available for microgrid clusters,current challenges,and solutions that have been proposed for these ***,it discusses the trend of protection schemes in networked microgrids and presents some conclusions related to ***—Adaptive eprotection,microgrid cluster,microgrid,multiple microgrid,networked microgrid,real-time simulation,smart grid.

关键词： Adaptive eprotection microgrid cluster microgrid multiple microgrid networked microgrid real-time simulation smart grid

Temporal stability and directional change in a color cline of a marine snail from NW Spain

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Current Zoology 2024年第2期70卷 163-173页

作者： juan Gefaell Ramon Vigo A.Honorato Gonzalez-Vazquez juan Galindo emilio Rolan-Alvarez Centro de Investigacion Marina Universidade de VigoDepartamento de BioquimicaGenetica e Inmunologia36310 VigoSpain

The evolution and maintenance of color clines is a classic topic of research in evolutionary ***,studies analyzing the temporal dynamics of such clines are much less frequent,due to the difficulty of obtaining reliable data about past color distributions along environmen-tal *** this article,we describe a case of decades-long temporal stability and directional change in a color cline of the marine snail Littorina saxatilis along the coastal inlet of the Ria de Vigo(NW Spain).*** from this area shows a clear color cline with 3 distinct areas from the innermost to the more wave-exposed localities of the Ria:the inner,protected localities show an abundance of fawn-like individuals;the intermediate localities show a high diversity of colors;and the outer,wave-exposed localities show populations with a high frequency of a black and lineated *** compare data from the 1970s and 2022 in the same localities,showing that the cline has kept relatively stable for at least over half a century,ex.ept for some directional change and local variability in the frequency of certain *** regression analyses and biodiversity measures are presented to provide clues into the selective pressures that might be involved in the maintenance of this color *** research avenues to properly test the explanatory power of these selective agents as well as the possible origins of the cline are discussed.

关键词： clinal variation color polymorphism ecological gradient Littorina saxatilis natural selection wave exposure.

Added Benefit of the early-Morning-Orbit Satellite Fengyun-3e on the Global Microwave Sounding of the Three-Orbit Constellation

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Advances in Atmospheric Sciences 2024年第1期41卷 39-52页

作者： juan LI Zhengkun QIN Guiqing LIU Jing HUANG CMA earth System Modeling and Prediction Centre Beijing 100081China State Key Laboratory of Severe Weather Chinese Academy of Meteorological SciencesBeijing 100081China Joint Center for Data Assimilation Research and Applications School of Atmospheric SciencesNanjing University of Information Science&TechnologyNanjing 210044China

The three-orbit constellation can comprehensively increase the spatial coverage of polar-orbiting satellites,but the polar-orbiting satellites currently in operation are only mid-morning-orbit and afternoon-orbit ***-3e(FY-3e)was launched successfully on 5 July 2021 in *** an early-morning-orbit satellite,FY-3e can help form a complete three-orbit observation system together with the mid-morning and afternoon satellites in the current mainstream operational *** this study,we investigate the added benefit of FY-3e microwave sounding observations to the midmorning-orbit Meteorological Operational satellite-B(Met Op-B)and afternoon-orbit Fengyun-3D(FY-3D)microwave observations in the Chinese Meteorological Administration global forecast system(CMA-GFS).The results show that the additional FY-3e microwave temperature sounder-3(MWTS-3)and microwave humidity sounder-2(MWHS-2)data can increase the global coverage of microwave temperature and humidity sounding data by 14.8% and 10.6%,*** enables the CMA-GFS to achieve nearly 100% global coverage of microwave-sounding observations at each analysis ***,after effective quality control and bias correction,the global biases and standard deviations of the differences between observations and model simulations are also *** on the Advanced Microwave Sounding Unit A and the Microwave Humidity Sounder onboard Met Op-B,and the MWTS-2 and MWHS-2 onboard FY-3D,adding the microwave sounding data of FY-3e can further reduce the errors of analysis results and improve the global prediction skills of CMA-GFS,especially for the southern-hemisphere forecasts within 96 hours,all of which are significant at the 95% confidence level.

关键词： data assimilation microwave temperature sounder MWTS-3

Quality evaluation of Nothofagus pumilio seeds linked to forest management and climatic events

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ecological Processes 2024年第1期13卷 98-107页

作者： Julian Rodríguez-Souilla Jimena e.Chaves María Vanessa Lencinas juan Manuel Cellini Fidel A.Roig Pablo L.Peri Guillermo Martinez Pastur Laboratorio de Recursos Agroforestales Centro Austral de Investigaciones Científicas (CADIC) Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET ) Laboratorio de Investigaciones en Maderas (LIMAD) Universidad Nacional de la Plata (UNLP) Instituto Argentino de Nivología Glaciología y Ciencias Ambientales (IAN-IGLA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET ) Instituto Nacional de Tecnología Agropecuaria (INTA) Universidad Nacional de la Patagonia Austral (UNPA) Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET )

Background Forest ecosystems undergo significant transformations due to harvesting and climate fluctuations, emphasizing the critical role of seeding in natural regeneration and long-term structural preservation. Climate change further amplifies these dynamics, affecting phenology across species and regions. In Tierra del Fuego(Argentina), Nothofagus pumilio(lenga) forests represent the most important timber resource, and it is managed through different silvicultural strategies. This species demonstrates notable post-disturbance regeneration, yet seed fall exhibits signifi-cant variability, leading to variations in seed quality(e.g., viability). This study aims to assess fluctuations in N. pumilio seed quality, determine how it varies concerning forest management strategies, annual productivity, and the co-occurrence of climatic phenomena including el Ni?o-Southern Oscillation(eNSO) and the Southern Annular Mode(SAM).Results Viable seeds represented 18.4% of the total, notably higher in unharvested than in managed areas. Con-versely, empty seeds were more prevalent in harvested areas(> 75%). Seed quality exhibited significant differences across silvicultural treatments, ex.ept for insect-predated seeds, which had similar proportions across all areas, though dispersed retention showed higher predation. When considering years with varying production levels, high-production years favoured full and viable seeds, particularly in unharvested forests and aggregated retention, while low-production years saw reduced viability across all treatments. Quadratic models revealed that viability increased with seed production, where unharvested forests achieved the highest values. Climate variability influenced seed proportions, where eNSO+/SAM+ promoting more full and viable seeds, while eNSO–/SAM+ favoured non-predated seeds, especially in unharvested *** Seed quality varies among treatments and years with different levels of seeding. Variations in seed qual-ity, l

关键词： Forest management Seeding Climate change extreme event Patagonia

Metal-metal bonds in Zintl clusters:Synthesis,structure and bonding in[Fe_(2)Sn_(4)Bi_(8)]^(3-)and[Cr_(2)Sb_(12)]^(3-)

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Chinese Chemical Letters 2024年第8期35卷 558-566页

作者： Ya-Nan Yang Zi-Sheng Li Sourav Mondal Lei Qiao Cui-Cui Wang Wen-juan Tian Zhong-Ming Sun John e.McGrady State Key Laboratory of element-Organic Chemistry Tianjin Key Lab for Rare Earth Materials and ApplicationsSchool of Materials Science and EngineeringNankai UniversityTianjin 300350China Department of Chemistry University of OxfordInorganic Chemistry LaboratoryOxfordOX13QRUnited Kingdom

We report here the synthesis and characterization of two new members of the M2 e 12 family of endohe-dral Zintl clusters,[Fe_(2)Sn_(4)Bi_(8)]^(3-)and[Cr_(2)Sb_(12)]^(3-),both of which contain open-shell metal dimers encap-sulated inside a triple-decker cluster of main-group *** 75-electron[Fe_(2)Sn_(4)Bi_(8)]^(3-)cluster has a D4h-symmetric structure,while[Cr_(2)Sb_(12)]^(3-),despite having the same 75-electron count,is strongly dis-torted to a geometry that resembles a CrSb_(8)crown capped by a CrSb_(4)*** structural differences between the two are driven by the increasing availability of 3d electron density in the earlier transi-tion metal,which leads,ultimately,to different electronic configurations in the two *** trends precisely mirror those observed in the Me_(10)and Me_(12)families containing a single transition metal ion.

关键词： Zintl anions endohedral clusters Metal-metal bond Second-order Jahn-Teller effect DFT calculation

A Stable Fe-FD Method for Anisotropic Parabolic PDes with Moving Interfaces

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Communications on Applied Mathematics and Computation 2024年第2期6卷 992-1012页

作者： Baiying Dong Zhilin Li juan Ruiz-Alvarez School of Civil and Hydraulic engineering NingXia UniversityYinchuan 750021NingxiaChina School of Mathematics and Computer Science NingXia Normal UniversityGuyuan 756000NingxiaChina Department of Mathematics North Carolina State UniversityRaleighNC 27695-8205USA Departamento de Matematica Aplicada y estadistica Universidad Politecnica de CartagenaCartagenaSpain

In this paper,a new finite element and finite difference(Fe-FD)method has been developed for anisotropic parabolic interface problems with a known moving interface using Cartesian *** the spatial discretization,the standard P,Fe discretization is applied so that the part of the coefficient matrix is symmetric positive definite,while near the interface,the maximum principle preserving immersed interface discretization is *** the time discretization,a modified Crank-Nicolson discretization is employed so that the hybrid Fe-FD is stable and second order *** terms are needed when the interface crosses grid *** moving interface is represented by the zero level set of a Lipschitz continuous *** ex.eriments presented in this paper confirm second orderconvergence.

关键词： Anisotropic parabolic interface problem Hybrid finite element and finite difference(Fe-FD)discretization Modified Crank Nicolson scheme

e2e-MFeRC:AMulti-Face expression Recognition Model for Group emotion Assessment

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Computers, Materials & Continua 2024年第4期79卷 1105-1135页

作者： Lin Wang juan Zhao Hu Song xiaolong xu Jiangsu Key Laboratory of Big Data Security&Intelligent Processing Nanjing University of Posts and TelecommunicationsNanjing210042China School of Network Security Jinling Institute of TechnologyNanjing211169China State Grid Jiangsu electric Power Company Limited Nanjing210000China School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing210042China

In smart classrooms, conducting multi-face expression recognition based on existing hardware devices to assessstudents’ group emotions can provide educators with more comprehensive and intuitive classroom effect analysis,thereby continuouslypromotingthe improvementof teaching ***,most existingmulti-face expressionrecognition methods adopt a multi-stage approach, with an overall complex process, poor real-time performance,and insufficient generalization ability. In addition, the existing facial expression datasets are mostly single faceimages, which are of low quality and lack specificity, also restricting the development of this research. This paperaims to propose an end-to-end high-performance multi-face expression recognition algorithm model suitable forsmart classrooms, construct a high-quality multi-face expression dataset to support algorithm research, and applythe model to group emotion assessment to expand its application value. To this end, we propose an end-to-endmulti-face expression recognition algorithm model for smart classrooms (e2e-MFeRC). In order to provide highqualityand highly targeted data support for model research, we constructed a multi-face expression dataset inreal classrooms (MFeD), containing 2,385 images and a total of 18,712 expression labels, collected from smartclassrooms. In constructing e2e-MFeRC, by introducing Re-parameterization visual geometry group (RepVGG)block and symmetric positive definite convolution (SPD-Conv) modules to enhance representational capability;combined with the cross stage partial network fusion module optimized by attention mechanism (C2f_Attention),it strengthens the ability to extract key information;adopts asymptotic feature pyramid network (AFPN) featurefusion tailored to classroomscenes and optimizes the head prediction output size;achieves high-performance endto-end multi-face expression detection. Finally, we apply the model to smart classroom group emotion assessmentand provide design refe

关键词： Multi-face expression recognition smart classroom end-to-end detection group emotion assessment

Sudden openings and gradual closures in canopy cover modulate acclimation,survival,and growth of a shade-tolerant rainforest tree species

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Journal of Forestry Research 2024年第5期35卷 78-90页

作者： Ana Paula Moretti Flavia Yesica Olguin juan Marcelo Gauna Corina Graciano INFIVe(CONICeT-Universidad Nacional de La Plata) Diagonal 113 N°4951900 La PlataProvincia de Buenos AiresArgentina CONICeT Godoy Cruz 2290C1425FQB Buenos AiresArgentina Facultad de Ciencias Agrariasy Forestales Universidad Nacional de La PlataCalle 60y 1181900 La PlataProvincia de Buenos AiresArgentina Facultad de Ciencias Forestales Universidad Nacional de MisionesBertoni 124 km 33380 EldoradoProvincia de MisionesArgentina

Forest disturbances at gap levels are one of the most important events for the regeneration and establishment of intermediate tree *** canopy openings expose plants to high light intensity and high evaporative demands that stress shade-acclimated ***,the slow closure of gaps reduces light availability to plants established when the incident irradiation was *** work evaluated the morphological and physiological acclimation of Cabralea canjerana(Vell)*** to sudden and to gradual changes in canopy cover.A pot ex.eriment was carried out with plants exposed to a sudden opening.A few days after the light shock,plants rapidly increased photosynthetic rates and decreased leaf water *** two months,plants activated physiological responses at leaf and whole plant levels to high light and water stresses,e.g.,increased stoma-tal conductance,stomatal index and reduction of leaf:fine roots ratio and *** seven months,hydraulic conductivity of petioles and the whole leaf increased,and growth was much higher than plants that remained under the *** a field ex.eriment in gaps in the rainforest,plants acclimated to all canopy *** years after planting,growth was maximum in open environments within the gaps,even if the canopy closed during the first 20 months after *** conclusion,if this species is planted to enrich the rainforest,positions within gaps with lower canopy cover should be chosen and gap closure will not affect *** manage *** natural regeneration,the opening of gaps and removal of understory will increase survival and growth without the risk that the stress caused by these sudden openings could lead to the death of ***-bining pot and field ex.eriments helps to understand the autecology of trees with particular ecological interest,and to build sound restoration practices.

关键词： Cabralea canjerana Atlantic forest Abiotic stress Regeneration Seedling

Simultaneous removal of 1,2-dichlorobenzene and furan over Mn-Ce-Fe oxide catalyst:Catalytic activity and product analysis

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Journal of Rare earths 2024年第5期42卷 972-979,I0006页

作者： juan Qiu Minghui Tang Yaqi Peng xuanhao Guo Shengyong Lu Jianhua Yan Taizhou Institute of Zhejiang University Taizhou 318000China State Key Laboratory for Clean energy Utilization Institute for Thermal Power EngineeringZhejiang UniversityHangzhou 310027China

The Mn-Ce-Fe mixed oxide(MCFe)was prepared by co-precipitation and the catalytic performance was tested by using 1,2-dichlorobenzene(1,2-DCB)and furan as model molecules of PCDD/*** effect of O_(2)concentration,SO_(2) and NO on the catalytic activity was *** 270℃,the MCFe oxide catalyst presents significant simultaneous removal efficiency of 75.25%and 100%for 1,2-DCB and furan,***-emmett-Teller(BeT)method(BeT),x-ray diffraction(xRD),scanning electron microscopy(SeM),x-ray photoelectron spectroscopy(xPS),Fourier transform infrared spectroscopy(FTIR),H_2-temperature programmed reduction(H_(2)-TPR),NH_(3)-temperature programmed desorption(NH_3-TPD)and O_(2)-TPD were used to characterize the catalysts before and after the *** tests suggest that the oxidation behavior of furan occurred prior to that of 1,*** to the intermediate products detected by gas chromatography-mass spectrometry(GC-MS),the by-products include chlorinated hydrocarbons,long-chain hydrocarbons,ketone,*** catalytic oxidation reaction paths are proposed.

关键词： 1 2-dichlorobenzene Furan Catalytic oxidation Product analysis Rare earths