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Developing knn forest data imputation for Catalonia

Journal of forestry Research 2024年第4期35卷 142-155页

作者： Timo Pukkala núria Aquilué Ariadna Just Jordi Corbera Antoni Trasobares forest Science and Technology Centre of Catalonia(CTfC) Crta.de St.Llorençde MorunysKm 225280 SolsonaSpain Cartographic and Geological Institute of Catalonia(ICGC) 08038 BarcelonaSpain

The combined use of LiDAR(Light Detection And Ranging)scanning and field inventories can provide spatially continuous wall-to-wall information on forest *** information can be used in many ways in forest mapping,scenario analyses,and forest manage-ment *** study aimed to find the optimal way to obtain continuous forest data for Catalonia when using knn imputation(knn stands for“k nearest neighbors”).In this method,data are imputed to a certain location from k field-measured sample plots,which are the most similar to the location in terms of LiDAR metrics and topographic *** multidimensional Euclidean distance was used as the similarity *** study tested two different methods to optimize the distance *** first method optimized,in the first step,the set of LiDAR and topographic variables used in the measure,as well as the transformations of these *** weights of the selected variables were optimized in the second *** other method optimized the variable set as well as their transformations and weights in one single *** two-step method that first finds the variables and their transfor-mations and subsequently optimizes their weights resulted in the best imputation *** the study area,the use of three to five nearest neighbors was *** and latitude turned out to be the most important variables when assessing the similarity of two locations of Catalan forests in the context of knn data *** optimal distance measure always included both LiDAR metrics and topographic *** study showed that the optimal similarity measure may be different for different ***,it was suggested that knn data imputation should always be started with the optimization of the measure that is used to select the k nearest neighbors.

关键词： forest inventory Differential evolution Simulated annealing LiDAR

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Two-Stream Approximation to the Radiative Transfer Equation:A new Improvement and Comparative Accuracy with Existing Methods

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Advances in Atmospheric Sciences 2024年第2期41卷 278-292页

作者： f.Momo TEMGOUA L.Akana nGUIMDO DnJOMO Environmental Energy Technologies Laboratory(EETL) Faculty of SciencesUniversity of YaoundéPO Box 812 YaoundéCameroon Department of Electrical and Electronic Engineering Faculty of Engineering and TechnologyUniversity of BueaPO Box 63 BueaCameroon

Mathematical modeling of the interaction between solar radiation and the Earth's atmosphere is formalized by the radiative transfer equation(RTE), whose resolution calls for two-stream approximations among other methods. This paper proposes a new two-stream approximation of the RTE with the development of the phase function and the intensity into a third-order series of Legendre polynomials. This new approach, which adds one more term in the expression of the intensity and the phase function, allows in the conditions of a plane parallel atmosphere a new mathematical formulation of γparameters. It is then compared to the Eddington, Hemispheric Constant, Quadrature, Combined Delta function and Modified Eddington, and second-order approximation methods with reference to the Discrete Ordinate(Disort) method(δ –128 streams), considered as the most precise. This work also determines the conversion function of the proposed new Method using the fundamental definition of two-stream approximation(f-TSA) developed in a previous work. notably,new Method has generally better precision compared to the second-order approximation and Hemispheric Constant methods. Compared to the Quadrature and Eddington methods, new Method shows very good precision for wide domains of the zenith angle μ 0, but tends to deviate from the Disort method with the zenith angle, especially for high values of optical thickness. In spite of this divergence in reflectance for high values of optical thickness, very strong correlation with the Disort method(R ≈ 1) was obtained for most cases of optical thickness in this study. An analysis of the Legendre polynomial series for simple functions shows that the high precision is due to the fact that the approximated functions ameliorate the accuracy when the order of approximation increases, although it has been proven that there is a limit order depending on the function from which the precision is lost. This observation indicates that increasing the order of app

关键词： Radiative Transfer Equation two-stream method Legendre polynomial optical thickness moments of specific intensity conversion function transmittance reflectance

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Measurement of yields and angular distributions ofγ-quanta from the interaction of 14.1 MeV neutrons with oxygen,phosphorus,and sulfur

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Chinese Physics C 2024年第3期48卷 79-92页

作者： D.n.Grozdanov n.A.fedorov S.B.Dabylova Yu.n.Kopatch I.n.Ruskov V.R.Skoy T.Yu.Tretyakova C.Hramco P.I.Kharlamov G.V.Pampushik P.G.filonchik A.V.Andreev Joint Institute for nuclear Research(JInR) DubnaRussia Institute for nuclear Research and nuclear Energy Bulgarian Academy of SciencesSofiaBulgaria faculty of Physics Lomonosov Moscow State UniversityMoscowRussia L.n.Gumilyov Eurasian national University AstanaKazakhstan Skobeltsyn Institute of nuclear Physics Moscow State UniversityMoscowRussia Institute of Chemistry of Moldova ChisinauRepublic of Moldova Moscow Institute of Physics and Technology MoscowRussia

A study of the inelastic scattering of neutrons with an energy of 14.1 MeV on the nuclei of oxygen,phosphorus,and sulfur was performed at the TAnGRA facility at JInR(Dubna).The experiment aimed to refine existing data and obtain new data on the yields and angular distributions ofγ-quanta emitted by the studied nuclei due to neutron-induced nuclear reactions using the tagged neutron *** types of detector systems were used to registerγ-***γ-ray yields were measured using a high-purity germanium(HPGe)*** angular distributions ofγ-rays were obtained using a system of 18 scintillation detectors based on bismuth germanite Bi_(4)Ge_(3)O_(12)(BGO)located around the *** performed experiments measured the yields of two transitions for the reaction of tagged neutrons with 16O,nine transitions for the reaction with ^(31)P,and nine transitions for the reaction with ^(32)S for the first *** angular anisotropy of theγ-radiation accompanying the inelastic scattering of neutrons with an energy of 14.1 MeV on ^(31)P nuclei was also measured for the first time.

关键词： tagged neutron method yields of gamma-quanta high-resolution gamma-spectrometry neutron-nuclear reactions neutron scattering

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Hard life for sons in the nest?Sex-dependent offspring mortality in Great Tits in urban and forest areas

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Avian Research 2024年第1期15卷 91-97页

作者： nora Agh Henriett Anna Dalvári Krisztián Szabó Ivett Pipoly András Liker HUn-REn-PE Evolutionary Ecology Research Group University of PannoniaH-8200VeszpremPf.1158.Hungary Behavioral Ecology Research Group Center for Natural SciencesUniversity of PannoniaH-8200Pf.1158.VeszpremHungary Molecular Ecology Research Group Department of EcologyUniversity of Veterinary Medicine BudapestH-1400Pf.2.BudapestHungary Synlab Hungary Ltd. H-1211Weiss Manfr´ed Str.5-7BudapestHungary

Sex-biased mortality can occur in birds during development,for example due to sexual differences in energy requirement and/or environmental sensitivity,or the effects of sex hormones or sex differences in the expression of mutations linked to sex *** extent of sex-bias in mortality may also be related to environmental conditions that influence offspring development and *** areas often provide poorer conditions for nestling development resulting in higher offspring mortality compared to natural areas,which may accelerate sex differences in offspring mortality in *** test this hypothesis,we examined the sex ratio of dead offspring in Great Tits(Parus major),using 427 samples of unhatched eggs and dead nestlings collected in two urban and two forest sites between 2013 and *** ratio of males in the whole sample of dead offspring(56.9%)was significantly higher than expected by an 1:1 ratio,and the strongest sex biases were detected in urban areas(57.6%males)and in young nestlings(f dead offspring did not differ significantly among study sites and between offspring developmental stages.29.3%of unhatched eggs contained a visible embryo,and the proportion of embryo-containing unhatched eggs did not differ significantly between urban and forest study *** results suggest male-biased offspring mortality in Great Tits,and highlight the need of large datasets to detect subtle differences between habitats and developmental stages.

关键词： Great Tit Urbanization nestling mortality Sex related differences

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Effectiveness of external prestressing in enhancing the non-ductile hanger failure mechanism in reinforced concrete inverted T-beams

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frontiers of Structural and Civil Engineering 2024年第7期18卷 1050-1065页

作者： Ahmed M.ATTA Reda n.BEHIRY Mohammed I.HARAZ Structural Engineering Department Faculty of EngineeringTanta UniversityTanta 33511Egypt nile Higher Institute for Engineering and Technology Mansoura 11001Egypt

Recently,inverted T-beams have been used in reinforced concrete(RC)bridges to support transverse precast *** T-beams,contrary to practice with conventional beams,are loaded on the flanges upper *** loading configuration causes hanger failure due to the generation of vertical tensile stresses near the bottom of the *** key purpose of this study is to investigate the efficiency of vertical external prestressing stainless-steel bars in mitigating non-ductile hanger failure in reinforced concrete inverted *** experimental study on six inverted-T beams,including two un-strengthened specimens,was carried *** study showed that the value of the prestressing level had a considerable impact on the performance of hanger mechanism in relation to crack pattern,ultimate loads,cracking behavior,load-deflection,strains,and *** experimental results indicated that the suggested method for strengthening inverted T-beams had efficacy in reducing the seriousness of the non-ductile hanger failure and resulted in a strength increase of up to 53% when compared to that of the un-strengthened ***,two analytical models for estimating the hanger capacity and the average crack width of the strengthened RC inverted T-beams were *** models that were proposed exhibited a high degree of agreement with the experimental results.

关键词： RC bridges inverted T-beams strengthening hanger failure external prestressing

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In-situ study of the microstructure evolution during tension of a Mg-Y-Zn-Al alloy processed by rapidly solidified ribbon consolidation technique

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Journal of Magnesium and Alloys 2024年第5期12卷 2024-2040页

作者： Jeno Gubicza Kristián Máthis Péter nagy Péter Jenei Zoltán Hegedus Andrea farkas Jozef Vesely Shin-ichi Inoue Daria Drozdenko Yoshihito Kawamura Department of Materials Physics Faculty of ScienceEotvos Loránd UniversityPázmány P.sétány 1/ABudapest H-1117Hungary Department of Physics of Materials Faculty of Mathematics and PhysicsCharles UniversityKe Karlovu 512116 Praha 2Czech Republic Deutsches Elektronen-Synchrotron DESY Notkestr.85Hamburg 22603Germany Magnesium Research Center Kumamoto University2-39-1 KurokamiChuo-kuKumamoto 860-8555Japan

Mg-Y-Zn-Al alloys processed by rapidly solidified ribbon consolidation(RSRC)technique exhibit an exceptional mechanical performance indicating promising application *** material has a bimodal microstructure consisting of fine recrystallized and coarse non-recrystallized grains with solute-rich stacking faults forming cluster arranged layers(CALs)and nanoplates(CAnaPs),or complete long period stacking ordered(LPSO)*** order to reveal the deformation mechanisms,in-situ synchrotron X-ray diffraction line profile analysis was employed for a detailed study of the dislocation arrangement created during tension in Mg-0.9%Zn-2.05%Y-0.15%Al(at%)*** uncovering the effect of the initial microstructure on the mechanical performance,additional samples were obtained by annealing of the as-consolidated specimen at 300 and 400℃ for 2 *** heat treatment at 300℃ had no significant effect on the initial microstructure,its evolution during tension and,thus,the overall deformation behavior under tensile *** the other hand,annealing at 400℃ resulted in a significant increase of the recrystallized grains fraction and a decrease of the dislocation density,leading to only minor degradation of the mechanical *** maximum dislocation density at the failure of the samples corresponding to the plastic strain of 10-25% was estimated to be about 16-20×10^(14)m^(-2).The diffraction profile analysis indicated that most dislocations formed during tension were of non-basal and pyramidal types,what was also in agreement with the Schmid factor values revealed independently from orientation *** was also shown that the dislocation-induced Taylor hardening was much lower below the plastic strain of 3% than above this value,which was explained by a model of the interaction between prismatic dislocations and CAnaPs/LPSO plates.

关键词： Mg-Zn-Y-Al alloy Long period stacking ordered(LPSO)phase Cluster arranged nanoplates(CAnaPs) Annealing Tension Dislocation density Hardening

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new evidence for the epigenetic regulation of skeletal stem cells

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Science Bulletin 2024年第13期69卷 2004-2006页

作者： Liming Zhao Jun Xiao Charles K.f.Chan Institute for Stem Cell Biology and Regenerative Medicine Stanford University School of MedicineStanford CA 94305USA Department of Surgery Division of Plastic and Reconstructive SurgeryStanford University School of MedicineStanford CA 94305USA Department of Orthopaedic Surgery Tongji HospitalTongji Medical CollegeHuazhong University of Science and TechnologyWuhan 430030China

Skeletal stem cells(SSCs)are crucial for skeletal development and regeneration,yet the epigenetic regulation of these cells remains poorly *** studies have delineated the epigenetic landscape across the developmental trajectory of SSCs,highlighting the involvement of Ptip in regulating SSC *** skeletal system undergoes dynamic remodeling throughout *** stem cells(SSCs),residing within the skeleton and lineage-restricted,serve as a cellular reserve to foster development and maintain skeletal *** categorized within the broader mesenchymal stromal/stem cells(MSCs).

关键词： skeletal involvement maintain

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Artificial ground freezing of underground mines in cold regions using thermosyphons with air insulation

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International Journal of Mining Science and Technology 2024年第5期34卷 643-654页

作者： Ahmad f.Zueter Mohammad Zolfagharroshan navid Bahrani Agus P.Sasmito Department of Civil and Resource Engineering Dalhousie UniversityHalifax B3H4R2Canada Department of Mining Engineering McGill UniversityMontreal H3A0E8Canada

Current practice of underground artificial ground freezing(AGf)typically involves huge refrigeration systems of large economic and environmental *** this study,a novel AGf technique is proposed deploying available cold wind in cold *** is achieved by a static heat transfer device called thermosyphon equipped with an air insulation layer.A refrigeration unit can be optionally integrated to meet additional cooling *** introduction of air insulation isolates the thermosyphon from ground zones where freezing is not needed,resulting in:(1)steering the cooling resources(cold wind or refrigeration)towards zones of interest;and(2)minimizing refrigeration *** design is demonstrated using well-validated mathematical models from our previous work based on two-phase enthalpy method of the ground coupled with a thermal resistance network for the *** Canadian mines are considered:the Cigar Lake Mine and the Giant *** results show that our proposed design can speed the freezing time by 30%at the Giant Mine and by two months at the Cigar Lake ***,a cooling load of 2.4 GWh can be saved at the Cigar Lake ***,this study provides mining practitioners with sustainable solutions of underground AGf.

关键词： Artificial ground freezing Underground mining Sustainable mining Thermosyphon Air insulation Cold regions

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Glyphosate as a direct or indirect activator of pro-inflammatory signaling and cognitive impairment

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neural Regeneration Research 2024年第10期19卷 2212-2218页

作者： Yukitoshi Izumi Kazuko A.O'Dell Charles f.Zorumski Department of Psychiatry Washington University School of MedicineSt.LouisMOUSA Taylor family Institute for Innovative Psychiatric Research Washington University School of MedicineSt.LouisMOUSA

Glyphosate-based herbicides are widely used around the world, making it likely that most humans have significant exposure. Because of habitual exposure, there are concerns about toxicity including neurotoxicity that could result in neurological, psychiatric, or cognitive impairment. We recently found that a single injection of glyphosate inhibits long-term potentiation, a cellular model of learning and memory, in rat hippocampal slices dissected 1 day after injection, indicating that glyphosate-based herbicides can alter cognitive function. Glyphosate-based herbicides could adversely affect cognitive function either indirectly and/or directly. Indirectly, glyphosate could affect gut microbiota, and if dysbiosis results in endotoxemia(leaky gut), infiltrated bacterial by-products such as lipopolysaccharides could activate pro-inflammatory cascades. Glyphosate can also directly trigger pro-inflammatory cascades. Indeed, we observed that acute glyphosate exposure inhibits long-term potentiation in rat hippocampal slices. Interestingly, direct inhibition of long-term potentiation by glyphosate appears to be similar to that of lipopolysaccharides. There are several possible measures to control dysbiosis and neuroinflammation caused by glyphosate. Dietary intake of polyphenols, such as quercetin, which overcome the inhibitory effect of glyphosate on long-term potentiation, could be one effective strategy. The aim of this narrative review is to discuss possible mechanisms underlying neurotoxicity following glyphosate exposure as a means to identify potential treatments.

关键词： cognitive impairment glyphosate microglia neuroinflammation roundup toll-like receptor 4 zinc chelation

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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

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