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Performance of evolutionary optimized machine learning for modeling total organic carbon in core samples of shale gas fields

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Petroleum 2024年第1期10卷 150-164页

作者： leonardo Goliatt C.M.Saporetti l.C.oliveira E.pereira Department of Computational and Applied Mechanics Federal University of Juiz de ForaJuiz de ForaBrazil Department of Computational Modeling Polytechnic InstituteRio de Janeiro State UniversityNova FriburgoBrazil Petrobras Rio de JaneiroBrazil Department of Stratigraphy and Paleontology Rio de Janeiro State UniversityRio de JaneiroBrazil

Rock samples'ToC content is the best indicator of the organic matter in source *** origin rock samples’analysis is used to calculate it manually by *** method requires time and resources because it relies on samples from many well intervals in source ***,research has been done to aid this *** learning algorithms can estimate total organic carbon instead of well logs and stratigraphic *** light of these efforts,the current work present a study on automating the total organic carbon estimation using machine learning approaches improved by an evolutionary methodology to give the model flexibility and *** algorithms,differential evolution,particle swarm optimization,grey wolf optimization,artificial bee colony,and evolution strategies were used to improve machine learning models to predict *** six metaheuristics were integrated into four machine learning methods:extreme learning machine,elastic net linear model,linear support vector regression,and multivariate adaptive regression *** samples from the YuDong-Nan shale gas field,located in the Sichuan basin,were used to evaluate the hybrid *** findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict *** results show that,independent of the metaheuristic used to guide the model selection,optimized extreme learning machines attained the best performance scores according to six *** hybrid models can be used in exploratory geological research,particularly for unconventional oil and gas resources.

关键词： Total organic carbon Hybrid models Automated machine learning Evolutionary algorithms Geology

Investigation of the effects of radial clearance on the screw conveyor performances for different inclinations

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Particuology 2024年第9期92卷 72-80页

作者： Berna Bolat Birgül Aşçıoğlu Temiztaş Enes Sezer Department of Mechanical Engineering Yıldız Technical University34349BeşiktaşİstanbulTurkey

Screw conveyors are widely used for bulk material *** study investigates the critical role of radial clearance,the gap between the screw and the conveyor body,on performance across various inclination *** Discrete Element Method(DEM)is employed to analyze the effects of different radial clearances on conveyor performance for concrete aggregate and sand as bulk *** efficiencies and capacity losses serve as key performance indicators,quantitatively assessed for each radial clearance and inclination *** validation is conducted to corroborate the *** the study,the optimal radial clearance was identified as 1.5 to 3 times of the particle *** optimal clearance minimizes the material jamming and increases the performance for screw conveyors with different inclinations and bulk material types as a result.

关键词： Screw conveyors Radial clearance Discrete element method(DEM) Volumetric efficiency Conveyor performance

Bresse Beam with Damping and logarithmic Source

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Chinese Annals of Mathematics,Series B 2024年第5期45卷 685-702页

作者： Sebasti?o CoRDEIRo Carlos BAlDEZ Carlos RAPoSo Ducival pereira octavio VERA Department of Mathematics Federal University of Pará Department of Mathematics State University of Pará Department of Mathematics University of Tarapacá

This paper investigates the stabilization of a Bresse system with internal damping and logarithmic source. The authors use the potential well theory. For initial data in the stability set created by the Nehari surface, the existence of a global solution is proved by using Faedo-Galerkin's approximation. The Nakao theorem gives the exponential decay.A numerical approach is presented to illustrate the results obtained.

关键词： 35A01 35B40 35l70 74H40 93D15 Bresse beam Exponential decay Global solution logarithmic source Numerical approach

Black hole shadows in Einstein-Bel-Robinson gravity

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Chinese Physics C 2024年第5期48卷 272-283页

作者： B.Hamil B.C.lütfüoğlu laboratoire de Physique Mathématique et Subatomique Facultédes Sciences ExactesUniversitéConstantine 1ConstantineAlgeria Department of Physics University of Hradec KrálovéRokitanského 6250003 Hradec KrálovéCzechia

Gravity models given by higher-order scalar curvature corrections are believed to bear important consequences. Einstein-Bel-Robinson (EBR) gravity with quartic curvature modification motivated Sajadi et al. to explore static spherically symmetric black hole solutions using perturbative methods. In this study, inspired by their work, we investigate AdS black hole shadows in EBR gravity and demonstrate how the gravity parameter alters the energy emission rate. Finally, we address the same problem in the presence of plasma, because the black holes are thought to be surrounded by a medium that changes the geodesic of photons.

关键词： black hole shadows Einstein-Bel-Robinson gravity plasma

Development and assessment of artificial neural network models for direct normal solar irradiance forecasting using operational numerical weather prediction data

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Energy and AI 2024年第1期15卷 88-101页

作者： Sara pereira Paulo Canhoto Rui Salgado Institute of Earth Sciences University ofÉvoraRua Romãao Ramalho 597000-671ÉvoraPortugal Department of Mechatronics Engineering University of´EvoraRua Romãao Ramalho 597000-671ÉvoraPortugal Physics Department University of´EvoraRua Romãao Ramalho 597000-671ÉvoraPortugal

Accurate operational solar irradiance forecasts are crucial for better decision making by solar energy system operators due to the variability of resource and energy *** numerical weather prediction(NWP)models can forecast solar radiation variables,they often have significant errors,particularly in the direct normal irradiance(DNI),which is especially affected by the type and concentration of aerosols and *** paper presents a method based on artificial neural networks(ANN)for generating operational DNI forecasts using weather and aerosol forecasts from the European Center for Medium-range Weather Forecasts(ECMWF)and the Copernicus Atmospheric Monitoring Service(CAMS),*** ANN models were designed:one uses as input the predicted weather and aerosol variables for a given instant,while the other uses a period of the improved DNI forecasts before the forecasted *** models were developed using observations for the location of´Evora,Portugal,resulting in 10 min DNI forecasts that for day 1 of forecast horizon showed an improvement over the downscaled original forecasts regarding R2,MAE and RMSE of 0.0646,21.1 W/m^(2)and 27.9 W/m^(2),*** model was also evaluated for different timesteps and locations in southern Portugal,providing good agreement with experimental data.

关键词： Solar radiation Solar energy Numerical weather prediction Artificial neural network operational forecasting

Effect of radiative loss mechanisms on FIR thermometric parameters of Nd^(3+)-doped lithium tellurite glasses

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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 Silva l.A.o.Nunes S.M.lima l.H.C.Andrade optical and Photothermal Spectroscopy 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 glasses 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 glass(samples 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 *** results indicate a strong dependence of the FIR parameters on the Nd^(3+)concentration,due to changes in the emission band profiles 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 samples 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 glass Fluorescence intensity ratio optical thermometry Judd-ofelt Rare earths

The Integration of Circular Economy and Impact Assessment: A Bibliometric Analysis

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Journal of Environmental Science and Engineering(A) 2024年第4期13卷 136-150页

作者： Marina Morhy pereira Marcelo Montaño São Carlos School of Engineering University of São PauloSão Carlos-SP 13563-120Brazil

In spite of the proximity between“CE(Circular Economy)”and“sustainability”,it is relevant to consider that a circular strategy is not inherently sustainable or free from significant environmental and social ***,assessing the impacts of CE initiatives and the promotion of circularity in development projects submitted to IA(Impact Assessment)processes are crucial,though the relationship between both fields has not been yet systematically ***,the present paper is focused on the identification of the links between IA and CE,based on the application of bibliometric techniques and Content *** outcomes revealed three thematic clusters in which significant overlaps were found:the 1st revealed lCA(life Cycle Assessments)as the most used IA technique to assess the impacts of CE strategies,the 2nd encompasses climate change and environmental issues,and the 3rd cluster revealed that the integration of sustainability is the most frequent objective linking IA and CE,though characterized by different *** findings allow concluding that IA fosters the transition to CE by assessing the impacts of circular initiatives and CE strategies can improve IA practice by making it more effective.

关键词： IA CE sustainability bibliometric analysis

Influence of preterm birth on the association between gestational diabetes mellitus and childhood developmental vulnerability:a causal mediation analysis

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World Journal of Pediatrics 2024年第1期20卷 54-63页

作者： Bereket Duko Amanuel Tesfay Gebremedhin Gizachew Assefa Tessema Gavin pereira Australian Centre for Precision Health UniSA Clinical and Health SciencesUniversity of South AustraliaNorth TerraceAdelaideSA5000Australia Curtin School of Population Health Faculty of Health SciencesCurtin UniversityKent StreetBentleyWA 6102Australia enAble Institute Curtin UniversityKent StreetBentleyWA6102Australia Centre for Fertility and Health(CeFH) Norwegian Institute of Public HealthOsloNorway

Background Epidemiological studies examining the direct and indirect effects of gestational diabetes mellitus(GDM)on offspring early childhood developmental vulnerability are ***,the aims of this study were to estimate the direct and indirect effects of GDM(through preterm birth)on early childhood developmental *** We conducted a retrospective population-based cohort study on the association between gestational diabetes mellitus and early childhood developmental vulnerability in children born in Western Australia(WA)using maternal,infant and birth records from the Midwives Notification,Hospitalizations,Developmental Anomalies,and the Australian Early Development Census(AEDC)*** used two aggregated outcome measures:developmentally vulnerable on at least one AEDC domain(DV1)and developmentally vulnerable on at least two AEDC domains(DV2).Causal mediation analysis was applied to estimate the natural direct(NDE),indirect(NIE),and total(TE)effects as relative risks(RR).Results In the whole cohort(n=64,356),approximately 22%were classified as DV1 and 11%as DV2 on AEDC *** of the natural direct effect suggested that children exposed to GDM were more likely to be classified as DV1(RR=1.20,95%CI:1.10-1.31)and DV2(RR=1.34,95%CI:1.19-1.50)after adjusting for potential *** 6%and 4%of the effect of GDM on early childhood developmental vulnerability was mediated by preterm birth for DV1 and DV2,*** Children exposed to gestational diabetes mellitus were more likely to be developmentally vulnerable in one or more AEDC *** biological mechanism for these associations is not well explained by mediation through preterm birth.

关键词： Child development Causal mediation analysis Gestational diabetes mellitus offspring

litter production and leaf nutrient concentration and remobilization in response to climate seasonality in the central Amazon

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Journal of Forestry Research 2024年第3期35卷 131-141页

作者： Ricardo Antonio Marenco Saul Alfredo Antezana-Vera Daniela pereira Dias luiz Antonio Candido Instituto Nacional de Pesquisas da Amazonia Coordenagao de Uso da Terra e Mudanca ClimaticaAv.Andre Araujo 2936ManausAM69067-375Brazil Programa de pos-Graduagao em Agricultura no Tropico Umido Instituto Nacional de Pesquisas da Amazonia-INPAManausAMBrazil Unidade Academica de Ciencias Agrarias Universidade Federal de JataiBR 364km 195JataiGO 75801-615Brazil

litterfall is the largest source of nutrients to for-est soils of tropical ***,variability in lit-terfall production,nutrient remobilization,and changes in leaf nutrient concentration with climate seasonality remain largely unknown for the central *** study meas-ured litterfall production,leaf nutrient remobilization,and leaf area index on a forest plateau in the central *** was measured at monthly intervals during 2014,while nitrogen,phosphorus,potassium,calcium and mag-nesium concentrations of leaf litter and canopy leaves were measured in the dry and rainy seasons,and remobilization rates *** area index was also recorded in the dry and rainy *** litterfall varied from 33.2(in the rainy season)to 87.6 g m^(-2) in the dry season,while leaf area index increased slightly in the rainy *** seasonality had no effect on concentrations of nitrogen,calcium,and magnesium,whereas phosphorous and potassium responded to rainfall seasonality *** phosphorous increased,potassium decreased during the dry *** seasons,nitrogen,potassium,and phosphorous decreased in leaf litter;calcium increased in leaf litter,while magnesium remained unaffected with leaf ***,the five nutrients had similar remobilization rates over the *** absence of climate seasonality on nutrient remobilization suggests that the current length of the dry season does not alter nutrient remobilization rates but this may change as dry periods become more prolonged in the future due to climate change.

关键词： Throughfall Nutrient cycling Climatic seasonality leaf mass per area