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Effect of radiative l.s. mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite gl.s.es

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Journal of Rare Earths 2024年第7期42卷 1250-1257,I0002页

作者： C.Y.Morassuti A.P.l.s.lva l.A.O.Nunes s.M.lima l.H.C.Andrade Optical and Photothermal.s.ectroscopy Group(GEOF) Center for Studies in Natural Resources(CERNA)State University of Mato Grosso do Sul(UEMS)C.P.351DouradosMSBrazil Renato Archer Information Technology Center Dom Pedro I Highway(SP-65)Km 1436-Chácaras Campos dos AmaraisCampinasSPBrazil Institute of Physics of são Carlos University of São PauloSão CarlosSPBrazil

Nd^(3+)-doped tellurite gl.s.es are promising materials for thermometers based on the fluorescence intensity ratio(FIR)***,at high Nd^(3+)concentrations,energy transfer(ET)processes such as optical reabsorption and cross-relaxation can affect the Nd^(3+)emission,which has been little explored in the ***,the present work investigated the use of Nd^(3+)-doped tellurite gl.s.(sampl.s.doped with Nd^(3+)at 0.2 mol%,0.5 mol%,2.0 mol%,and 4.0 mol%)in fluorescence thermometers,in the temperature range from 299 to 371 *** resul.s.indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profil.s.caused by optical reabsorption of the Nd^(3+)emissions and cross-relaxation processes.A decrease of the relative sensitivity of the ratio^(4)F_(5/2)→^(4)I_(9/2)/^(4)F_(3/2)→^(4)I_(9/2)is observed for sampl.s.doped with higher amounts of Nd^(3+).The maximum relative sensitivity at 299 K is 3.00%/K,which is the highest value among the reported Nd^(3+)ions.

关键词： Nd^(3+)-doped tellurite gl.s. Fluorescence intensity ratio Optical thermometry Judd-Ofelt Rare earths

Weighted Probability Density Estimator with Updated Bandwidths

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Journal of systems science & Complexity 2024年第2期37卷 886-906页

作者： WU Yi YU Wei WANG Xuejun PRAKAsA RAO B l s school of Big Data and Artificial Intelligence Chizhou UniversityChizhou 247000China school of Big Data and statistics Anhui UniversityHefei 230601China CR Rao Advanced Institute of Mathematics Statistics and Computer ScienceHyderabad 500046India

In this paper,the authors study a cl.s. of weighted version of probability density *** is shown that the weighted estimator contains some existing estimators of probability density,no matter they are recursive or *** statistical resul.s.including weak consistency,strong consistency,rate of strong consistency,and asymptotic normality are establ.s.ed under some mild ***,the random weighted estimator is also *** numerical.s.mulations and a real data anal.s.s are presented to study the numerical performances of the estimators.

关键词： Asymptotic normality consistency numerical.s.mulation probability density real data anal.s.s updated bandwidths weighted estimator

Model Change Active learning in Graph-Based semi-supervised learning

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Communications on Applied Mathematics and Computation 2024年第2期6卷 1270-1298页

作者： Kevin s.Miller Andrea l.Bertozzi Department of Mathematics University of CaliforniaLos Angeles520 Portola PlazaLos AngelesCA 90095USA

Active learning in semi-supervised cl.s.ification involves introducing additional labels for unlabelled data to improve the accuracy of the underlying cl.s.ifier.A challenge is to identify which points to label to best improve performance while limiting the number of new labels."Model Change"active learning quantifies the resulting change incurred in the cl.s.ifier by introducing the additional label.s..We pair this idea with graph-based semi-supervised learning(ssl)methods,that use the spectrum of the graph laplacian matrix,which can be truncated to avoid prohibitively large computational and storage *** consider a family of convex l.s. functions for which the acquisition function can be efficiently approximated using the laplace approximation of the posterior *** show a variety of multicl.s. exampl.s.that ill.s.rate improved performance over prior state-of-art.

关键词： Active learning Graph-based methods semi-supervised learning(ssl) Graph laplacian

Resource management at the network edge for federated learning

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Digital Communications and Networks 2024年第3期10卷 765-782页

作者： silvana Trindade luiz F.Bittencourt Nelson l.s.da Fonseca Institute of Computing State University of CampinasCampinasBrazil

Federated learning has been explored as a promising solution for training machine learning models at the network edge,without sharing private user *** limited resources at the edge,new solutions must be developed to leverage the software and hardware resources as the existing solutions did not focus on resource management for network edge,specially for federated *** this paper,we describe the recent work on resource manage-ment at the edge and explore the challenges and future directions to allow the execution of federated learning at the *** such as the discovery of resources,deployment,load balancing,migration,and energy effi-ciency are discussed in the paper.

关键词： Resource management Edge computing Federated learning Machine learning

Mechanical Behavior of Panels Reinforced with Orthogonal Plant Fabrics: Experimental and Numerical Assessment

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Journal of Renewable Materials 2024年第10期12卷 1791-1810页

作者： Martha l.s.nchez G.Capote Universidad Militar Nueva Granada Programa de Ingeniería CivilBogotá110111Colombia Facultad de Ciencias Departamento de FísicaUniversidad Nacional de ColombiaBogotá111321Colombia

The construction sector is one of the main sources of pollution,due to high energy consumption and the toxic substances generated during the processing and use of traditional *** production of cement,steel,and other conventional materials impacts both ecosystems and human health,increasing the demand for ecological and biodegradable *** this paper,we analyze the properties of panels made from a combination of plant fibers and castor oil resin,analyzing the viability of their use as construction *** the research,orthogonal fabrics made with waste plant fibers supplied by a company that deals with the manufacture of furniture and craft products were *** fabrics were made with strips of plant fibers of the Calamus rotang,Bambusa vulgaris,Heteropsis flexuosa,and salix viminal.s.*** improve their compatibility with the castor oil resin,a cold argon pl.s.a treatment was *** effect of the treatment on the properties of the fibers and the panels was *** density,water absorption capacity,and swelling percentage were ***,compression,static bending,and linear buckling tests were carried *** study found that panels made with treated fiber fabrics exhibited a reduction of approximately 10%in absorption capacity and up to 35%in swelling percentage *** made with Bambusa vulgaris fabrics exhibited the highest strength and stiffness *** models were constructed using commercial finite element *** comparing the numerical resul.s.with the experimental ones,differences of l.s. than 15%were seen,demonstrating that the models allow adequately predicting the analyzed *** comparing the values obtained with the characteristic values of oriented strand board,the resul.s.suggest that panels made with unconventional materials could replace commercial panels traditionally made with wood-based fibers and particl.s.and other composite materials in several applications in th

关键词： Unconventional materials nonstructural panels plantﬁbers surface treatment physical properties mechanical properties

Four late-type Galaxies with Double Radio lobes and Properties of such Galaxies

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Research in Astronomy and Astrophysics 2024年第4期24卷 84-90页

作者： Z.s.Yuan X.Y.Gao Z.l.Wen J.l.Han National Astronomical Observatories Chinese Academy of SciencesBeijing 100101China CAs Key laboratory of FAsT National Astronomical ObservatoriesChinese Academy of SciencesBeijing 100101China school of Astronomy and space sciences University of Chinese Academy of SciencesBeijing 100049China

The triggering mechanism for radio lobes from late-type galaxies is not fully *** sampl.s.are desired for a thorough investigation and *** utilizing the optical data from the newly released Dark Energy spectroscopic Instrument imaging surveys and the radio sources from the NRAO VlA sky survey and the Faint Images of the Radio sky at Twenty-centimeter,we identify four late-type Galaxies with double Radio lobes(la GRls):J0217-3645,J0947+6220,J1412+3723 and J1736+*** previously known la GRls,we confirm the correlation between radio power P_(1.4GHz)and stellar mass M_(*)of host ***(25/35)la GRls belong to the blue cloud galaxies,while the newly identified cases in this work are located within the region of the red *** find a clear correlation between the differential radio power,i.e.,the offset from the P_(1.4GHz)-M_(*)relation,and the galaxy color,indicating that bluer galaxies at a fixed M_(*)tend to host more powerful radio ***,the majority(31/36)of la GRls are either located in a galaxy group or displaying a disturbed *** suggest that all of the galaxy mass,color and surrounding environment could play important rol.s.in triggering radio lobes in late-type galaxies.

关键词： galaxies:active galaxies:jets galaxies:spiral radio continuum:galaxies

In search of a pan-coronavirus vaccine:next-generation vaccine design and immune mechanisms

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Cellular & Molecular Immunology 2024年第2期21卷 103-118页

作者： s.Cankat M.U.Demael l.s.adling Division of Infection and Immunity Institute of Immunity and TransplantationUniversity College LondonPears BuildingLondon NW32PPUK

Members of the coronaviridae family are endemic to human populations and have caused several epidemics and pandemics in recent *** this review,we will discuss the feasibility of and progress toward the ultimate goal of creating a pan-coronavirus vaccine that can protect against infection and disease by all members of the coronavirus *** will detail the unmet clinical need associated with the continued transmission of sARs-CoV-2,MERs-CoV and the four seasonal coronaviruses(HCoV-OC43,Nl63,HKU1 and 229E)in humans and the potential for future zoonotic *** will highlight how first-generation sARs-CoV-2 vaccines and natural history studies have greatly increased our understanding of effective antiviral immunity to coronaviruses and have informed next-generation vaccine *** will then consider the ideal properties of a pan-coronavirus vaccine and propose a blueprint for the type of immunity that may offer ***,we will describe a subset of the diverse technologies and novel approaches being pursued with the goal of developing broadly or universally protective vaccines for coronaviruses.

关键词： Vaccine Coronavirus Cross-reactive immunity Cross-protection Universal

Impact on soil Organic C and Total.s.il N from Cool- and Warm-season legumes Used in a Green Manure-Forage Cropping system

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Agricultural.s.iences 2024年第3期15卷 333-357页

作者： Clark B. Neely Francis M. Rouquette Jr. Cristine l.s. Morgan Frank M. Hons William l. Rooney Gerald R. smith Department of soil and Crop science Washington State University Pullman WA USA Texas A&M Agrilife Research Overton TX USA Chief scientific Officer Soil Health Institute Morrisville NC USA Department of soil and Crop science Texas A&M University College Station TX USA

Annual forage legumes are important components of livestock production systems in East Texas and the southeastern Us. Forage legumes contribute nitrogen (N) to cropping systems through biological N fixation, and their seasonal biomass production can be managed to complement forage grasses. Our research objectives were to evaluate both warm- and cool.s.ason annual forage legumes as green manure for biomass, N content, ability to enhance soil organic carbon (sOC) and soil N, and impact on post season forage grass crops. Nine warm-season forage legumes (Wsl) were spring planted and incorporated as green manure in the fall. Forage rye (secale cereale l.) was planted following the incorporation of Wsl treatments. Eight cool.s.ason forage legumes (Csl) were fall planted in previously fallow plots and incorporated as green manure in late spring. sorghum-sudangrass (sorghum bicolor x sorghum bicolor var. sudanense) was planted over all treatments in early summer after forage rye harvest and incorporation of Csl treatments. sorghum-sudangrass was harvested in June, August and september, and treatments were evaluated for dry matter and N concentration. soil cores were taken from each plot, split into depths of 0 to 15, 15 to 30 and 30 to 60 cm, and soil C and N were measured using combustion anal.s.s. Nylon mesh bags containing plant sampl.s.were buried at 15 cm and used to evaluate decomposition rate of above ground legume biomass, including change in C and N concentrations. Mungbean (Vigna radiata l. [Wilczek]) had the highest shoot biomass yield (6.24 t DM hasup>-1sup>) and contributed the most total N (167 kg∙hasup>-1sup>) and total C (3043 kg∙hasup>-1sup>) of the Wsl tested. Decomposition rate of Wsl biomass was rapid in the first 10 weeks and very slow afterward. Winter pea (Pisum sativum l. spp. sativum), arrow leaf clover (Trifolium vesicul.s.m savi.), and crimson clover (Trifolium incarnatum l.) were the most productive Csl in this trial. Austrian winter pea

关键词： Annual legumes soil N soil Organic C Green Manure Deer Browse Forage Cropping systems

Adsorption of yttrium(Y^(3+)) and concentration of rare earth elements from phosphogypsum using chitin and chitin aerogel

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Journal of Rare Earths 2024年第4期42卷 775-782页

作者： Glaydson s.dos Reis Diana Pinto sabrina F.lütke Eder C.lima luis F.O.silva Irineu A.s.De Brum Guilherme l.Dotto Department of Forest Biomaterials and Technology Biomass Technology Centre Swedish University of Agricultural SciencesUmeaE13Swedn Universidad De la Costa Calle 58#55-66080002BarranquillaAtlanticoColombia Research Group on Adsorptive and Catalytic Process Engineering(ENGEPAC) Federal University of Santa MariaAv.Roraima100079705900Santa MariaRSBrazil Institute of Chemistry Federal University of Rio Grande do Sul90040060Porto AlegreBrazil

Chitin powder and chitin-aerogel were prepared from shrimp wastes and used to uptake Y^(3+)from aqueous solutions and concentrate this rare earth element from phosphogypsum(PG).Chitin aerogel displays a specific surface area of 945 m^(2)/g,while chitin powder is 3.6 m^(2)/g,which largely influences its adsorption *** the adsorption in synthetic solutions,the effect of pH on Y^(3+)removal is strong for chitin powder *** contrast,no big pH influence was detected for chitin *** interactions and chelation can highlight the proposed mechanism of Y^(3+)on chitin adsorbents for the powder and ***,in addition to these interactions,pore filling/pore diffusion is the main mechanism of Y^(3+)removal in the chitin *** aerogel is efficient in concentrating 8 times the Y^(3+)from PG,a very complex *** complex chitin aerogel-Y^(3+)can be a secondary source of rare earth elements for other applications.

关键词： Rare earths sustainable material Chitin powder Chitin porous aerogel Yttrium adsorption and recovery