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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 Fora Department of computational Modeling Polytechnic Institute Rio de Janeiro State University Petrobras Department of Stratigraphy and Paleontology Rio de Janeiro State University

Rock samples' TOc content is the best indicator of the organic matter in source rocks. The origin rock samples' analysis is used to calculate it manually by specialists. This method requires time and resources because it relies on samples from many well intervals in source rocks. Therefore, research has been done to aid this effort. Machine learning algorithms can estimate total organic carbon instead of well logs and stratigraphic studies. In light of these efforts, the current work present a study on automating the total organic carbon estimation using machine learning approac.es improved by an evolutionary methodology to give the model flexibility and precision. Genetic algorithms, differential evolution, partic.e swarm optimization, grey wolf optimization, artificial bee colony, and evolution strategies were used to improve machine learning models to predict TOc. The six metaheuristics were integrated into four machine learning methods: extreme learning machine, elastic net linear model, linear support vector regression, and multivariate adaptive regression splines. core samples from the YuDong-Nan shale gas field, located in the Sichuan basin, were used to evaluate the hybrid strategy. The findings show that combining machine learning models with an evolutionary algorithms in a hybrid fashion produce flexible models that accurately predict TOc. The 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 metrics. Such 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

effects of dust controls on respirable coal mine dust composition and partic.e sizes:case studies on auxiliary scrubbers and canopy air curtain

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International Journal of coal Sc.ence & Technology 2024年第3期11卷 86-101页

作者： F.Animah c.Keles W.R.Reed e.Sarver Department of Mining and Minerals engineering Virginia Polytechnic Institute&State UniversityBlacksburgVAUSA National Institute of Occupational Safety and Health(NIOSH) PittsburghPAUSA

control of dust in underground coal mines is critical for mitigating both safety and health *** decades,the National Institute of Occupational Safety and Health(NIOSH)has led research to evaluate the effectiveness of various dust control technologies in coal *** studies have included the evaluation of auxiliary scrubbers to reduce respirable dust downstream of active mining and the use of canopy air curtains(cAcs)to reduce respirable dust in key operator *** detailed dust charac.erization was not a focus of such studies,this is a growing area of *** preserved filter samples from three previous NIOSH studies,the current work aims to explore the effect of two different scrubbers(one wet and one dry)and a roof bolter cAc on respirable dust composition and partic.e size *** this,the preserved filter samples were analyzed by thermogravimetric analysis and/or scanning electron microscopy with energy dispersive *** indicate that dust composition was not appreciably affec.ed by either scrubber or the ***,the wet scrubber and cAc appeared to dec.ease the overall partic.e size *** an effect of the dry scrubber was not consistently observed,but this is probably related to the particular sampling location downstream of the scrubber which allowed for significant mixing of the scrubber exhaust and other return *** from the insights gained with respect to the three specific dust control case studies revisited here,this work demonstrates the value of preserved dust samples for follow-up investigation more broadly.

关键词： Respirable dust Dust control SeM–eDX Scrubber canopy air curtain Silica

Investigations of nuc.ear chirality at iThemba LABS

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Frontiers of physics 2024年第2期19卷 7-38页

作者： R.A.Bark e.A.Lawrie c.Liu S.Y.Wang iThemba Laboratory for Ac.elerator Based Sc.ences National Research FoundationP.O.Box 722Somerset-West 7129South Africa Department of Physics University of the Western CapePrivate Bag X177535BellvilleSouth Africa Shandong Provincial Key Laboratory of Optical Astronomy and Solar-Terrestrial environment Institute of Space SciencesShandong UniversityWeihai 264209China

Progress in the studies of chirality in atomic nuc.ei at iThemba LABS is *** regions of chirality,around mass 80 and 190 have been discovered using the AFRODITe array,specifically in the nuc.ei^(74)As,^(78,80,82)Br,^(81)Kr,and^(193,194,198)*** phenomena have been observed,including multiple chiral bands in the same nuc.eus,the c.existence of octupole correlations and nuc.ear chirality,and the c.existence of pseudo spin and nuc.ear *** best example of chiral degeneracy to date was found in ^(194)*** level sc.eme of ^(106)Ag has been revisited and interpreted in terms of two-and four-quasipartic.e *** using the partic.e-rotor model have shown that the fingerprints of chirality in the two-quasipartic.e system only can occur in an idealised model *** systems with a higher number of quasipartic.es,the calculations showed that nuc.ear chirality can persist.

关键词： chirality high-spin states partic.e-rotor model

All-electron basis sets for H to Xe specific for ZORA calculations:Applications in atoms and molecules

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chinese Physics B 2024年第8期33卷 238-246页

作者： c.S.Gomes F.e.Jorge A.canal Neto Departamento de Fisica Universidade Federal do Espirito Santo29075-910 VitoriaESBrazil Departamento de Fisica Instituto de Ciencias Exatas e BiologicasUniversidade Federal de Ouro Preto Campus Universitario Morro do Cruzeiro35402-136 Ouro PretoMGBrazil

A segmented basis set of quadruple zeta valence quality plus polarization functions(QZP)for H through Xe was developed to be used in conjunction with the ZORA *** set was augmented with diffuse functions to describe electrons farther away from the nuc.ei *** the ZORA-ccSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequenc.es,and atomization energies of some molecules were *** addition of core-valence corrections has been shown to improve the agreement between theoretical and experimental results for molecular *** atomization energies,a similar observation emerges when considering spin-orbit *** the augmented QZP-ZORA set,static mean dipole polarizabilities of a set of atoms were calculated and compared with previously published recommended and experimental *** evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for each property studied.

关键词： QZP-ZORA and AQZP-ZORA basis sets elements from H to Xe ccSD(T)method atomic and molecular properties

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Slope stability of reclaimed coal mines through a new water filling index

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Journal of Rock Mechanics and Geotechnical engineering 2024年第3期16卷 828-839页

作者： Antonios Mikroutsikos Alexandros I.Theocharis Nikolaos c.Koukouzas Ioannis e.Zevgolis c.emical Process&energy Resources Institute Centre for Research&Technology HellasAthensGreece School of Mining and Metallurgical engineering National Technical University of AthensAthensGreece

A common reclamation practice for closed coal surface mines is filling them with water to form pit *** c.eation and sustainability of these lakes are significantly affec.ed by the stability of the corresponding *** present study provides a general framework for analyzing the water filling’s effect on slope stability based on a new water filling index,which can indirectly consider the factors affecting the process and effic.ently quantify the filling speed’s *** assumptions of the proposed approach are thoroughly discussed,and the range of the water filling index is ***,the safety factor is calculated using the finite element method with the shear strength reduction technique during the filling process for various conditions(soil properties,slope geometry,hydraulic conditions,and water filling speed).Results are presented as normalized stability charts for practical *** the water filling,the stability gradually dec.eases until the reservoir reac.es a critical level of 10%e40%of the total height;it then inc.eases to even more stable conditions than the initial ***,the present analysis allows for the preliminary stability evaluation of a coal mine during the formation of a pit lake and the appropriate quantification of the water filling’s effect.

关键词： Post-coal era Open-pit flooding Stability charts critical level

comparisons of oxbow lake fish assemblages in relation to bigheaded carp establishment in the lower White River, Arkansas

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ecological Processes 2024年第1期13卷 188-205页

作者： Michael A.eggleton cody J.Salzmann Joseph e.Kaiser Shannon c.F.Smith Department of Aquaculture and Fisheries University of Arkansas at Pine Bluff Arkansas Game and Fish commission Virginia Institute of Marine Sc.ence

Background Since the late 1990s, bigheaded carps(largely silver carp [Hypophthalmichthys molitrix] but also bighead carp [H. nobilis]) have established throughout the lower Mississippi River basin. Using previously studied oxbow lakes in the lower White River basin, Arkansas, we compared current(2017, “post-carp” establishment) fish assemblages to historical(2002, “pre-carp” establishment) fish assemblages. Fish assemblages were comprehensively assessed using multiple gears, including boat electrofishing, mini-fyke nets, and experimental small-mesh gill *** T-tests suggested that fish assemblage indices of richness, diversity, evenness, and dominance were often greater(P e post-carp period as reflec.ed by boat electrofishing and experimental gill nets. However, all indices were generally similar(P > 0.05) between the pre-carp and post-carp period with fish assemblages depic.ed using mini-fyke nets. Nonmetric multidimensional scaling analyses indicated that fish assemblages differed structurally between pre-carp and post-carp periods. Assemblage differences were linked to both small and large abundance changes for more than 20 spec.es. Abundances of gizzard shad(Dorosoma cepedianum), emerald shiner(Notropis atherinoides), pugnose minnow(Opsopoeodus emiliae), crappies(Pomoxis spp.), bluegill(Lepomis macrochirus), orangespotted sunfish(L. humilis), and yellow bass(Morone mississippiensis) declined between the pre-carp and postcarp periods. conversely, abundances of weed shiner(N. texanus), pallid shiner(Hybopsis amnis), longear sunfish(L. megalotis), buffalofishes(Ictiobus spp.), and gars(Lepisosteus spp.) generally inc.eased during the same *** Although not possible to conclude assemblage shifts were entirely related to bigheaded carps due to the absence of an appropriate reference system where carps did not establish, the wide establishment of these carps is one of the most pervasive changes to have occurred in the lower White

关键词： Bigheaded carp Silver carp Aquatic nuisance spec.es Fish assemblage Oxbow lake Large river

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

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c.ee 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 Ic.eA 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 sc.emes have become essential for reliable and secure operation of networked *** protection sc.emes that allow correct operation of microgrids have been proposed for individual systems in different topologies and ***,protection sc.emes for networked microgrids are still in devel-opment,and further research is required to design and operate advanced protection in interconnec.ed *** of these microgrids in different nodes with various intercon-nection technologies inc.eases 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 artic.e 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 sc.emes 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

cellulose synthesis in land plants

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Molecular Plant 2024年第2期17卷 359-361页

作者： Gustav B.Pedersen Leonard Blasc.ek Kristian e.H.Frandsen Lise c.Noack Staffan Persson 不详

After the original publication of the above artic.e,we and/or attentive readers identified several instances of unc.ear or erroneous writing that needed correcting,as *** are added for emphasis.

关键词： synthesis instance identif

Barosinusitis due to routine weather changes:A cross-sectional analysis of public websites

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World Journal of Otorhinolaryngology-Head and Neck Surgery 2024年第1期10卷 18-23页

作者： James c.campbell Julia e.canick Philip G.c.en Ralph Abi Hac.em David W.Jang Department of Head and Neck Surgery&communication Sc.ences Duke University School of MedicineDurhamNorth CarolinaUSA Duke University School of Medicine DurhamNorth CarolinaUSA Department of Otolaryngology-Head and Neck Surgery University of Texas Health Science Center San AntonioSan AntonioTexasUSA

Background:Sinusitis is a common diagnosis that can be erroneously associated with routine weather‐related barometric pressure *** actuality,these pressure changes likely exacerbate migraine headac.es,which can cause facial pain and pressure rather than true sinus ***:The present study sought to charac.erize the representation of both sinusitis and migraine in association with barometric pressure changes across websites on the ***:An Internet search for relevant terms was conduc.ed,and content of the resulting pages was assessed for associations between weather‐related pressure changes and either sinusitis or *** in reported results across different subtypes of Internet sources were *** primary outcomes measured were(1)whether a given media source associated barometric weather changes with sinusitis,(2)whether that source associated barometric weather changes with migraine,and(3)treatment options offered by that ***:Of the 116 included webpages,36(31.03%)associated sinusitis and routine barometric pressure *** these,10(27.77%)were otolaryngology practice ***‐seven webpages(57.76%)associated migraine and routine barometric pressure *** these,nonotolaryngology webpages were more likely to report this ***:Otolaryngology practice sites were observed to be the most frequent professional medical resource reporting the unsubstantiated claim that routine barometric pressure changes are associated with *** sources were more likely to link weather‐related pressure changes to *** results suggest that opportunities exist for otolaryngology practice sites to educate patients about nonrhinogenic headac.e etiologies.

关键词： acute rhinosinusitis balloon sinus dilation headac.e migraine sinusitis

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