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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.c.rrent 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 precision. Genetic algorithms, differential evolution, particle swarm optimization, grey wolf optimization, artificial bee.c.lony, 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

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 vale.c. 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 de.c.ibe electrons farther away from the nuclei *** the ZORA-ccSD(T)/QZP-ZORA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational freque.c.es,and atomization energies of some molecules were *** addition of core-vale.c. 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.c.lculated and compared with previously published recommended and experimental *** evaluations of the ZORA and Douglas–Kroll–Hess Hamiltonians were made for e.c. property studied.

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

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

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Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon c.Dae.c.ler Katelyn J.W.So Konstantin feinberg Marina Manoraj Jenny cheung Jennifer Zhang Kaveh Mirmoeini JPaul Santerre Tessa Gordon Gregory HBorschel SickKids Research Institute Neuroscience and Mental Health ProgramTorontoONCanada Institute of Biomaterials and Biomedical engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA Division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong ***,there are no FDA-approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve *** authors de.c.ibe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug *** is e.c.psulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large.c.liber nerves,and the wrap degrades within 120 days into biocompatible *** released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegradable local drug delivery nerve injury nerve regeneration nerve wrap tacrolimus

Investigations of nuclear 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 Accelerator Based Scie.c.s 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 nuclei at iThemba LABS is *** regions of chirality,around mass 80 and 190 have been discovered using the AFRODITe array,specifically in the nuclei^(74)As,^(78,80,82)Br,^(81)Kr,and^(193,194,198)*** phenomena have been observed,including multiple.c.iral bands in the same nucleus,the.c.existe.c. of octupole.c.rrelations and nuclear chirality,and the.c.existe.c. of pseudo spin and nuclear *** best example of chiral degeneracy to date was found in ^(194)*** level scheme of ^(106)Ag has been revisited and interpreted in terms of two-and four-quasiparticle *** using the particle-rotor model have shown that the fingerprints of chirality in the two-quasiparticle system only can occur in an idealised model *** systems with a higher number of quasiparticles,the.c.lculations showed that nuclear chirality can persist.

关键词： chirality high-spin states particle-rotor model

effects of dust controls on respirable.c.al mine dust composition and particle sizes:case studies on auxiliary scrubbers and canopy air curtain

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International Journal of coal Scie.c. & 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 characterization was not a focus of such studies,this is a growing area of *** preserved filter samples from three previous NIOSH studies,the.c.rrent 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 particle 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 affected by either scrubber or the ***,the wet scrubber and cAc appeared to decrease the overall particle 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

Decision and coordination of an e.c.mme.c. Supply chain considering Returns and Network externalities

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Journal of Systems Scie.c. and Systems engineering 2024年第5期33卷 552-575页

作者： Liang Shen Fei Lin Yuyan Wang Luping Ding T.c.e.c.eng Dexia Wang School of Public Finance and Taxation Shandong University of Finance and Economicsjinan 250014China bschool of Management Scie.c. and engineering Shandong University of Finance and EconomicsJinan 250014China PolyU Business School The Hong Kong Polytechnic UniversityHung HomKowloonHong Kong 999077China

considering the large number of returns in online sales and the network externalities of e-platforms,we develop a decentralized model and a centralized model to explore the impacts of returns and network externalities on e.c.mme.c. supply chain(ecSc)*** show that in the decentralized model,the service level,price,market demand,and ecSc members’profits increase with the network externality ***,the service level and price increase,while the market demand and ecSc members’profits decrease with the product return *** centralized model is the optimal operating mode when it is properly *** design the.c.mmission and return cost-sharing”contract to optimize ecSc,in which the proportion of the e-platform’s sharing of the return handling cost is exactly equal to the proportion of the system profit after *** on the decentralized model,we develop two extended models in which we endogenize the impacts of the service level and return rate on the network externality *** comparisons between the extended and decentralized models,we show that high-quality service.c.n improve ecSc’s profitability,while a high return rate hurts its economic performance.

关键词： e.c.mme.c. supply chain coordination mechanism network externalities return products

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.The.c.aris Nikolaos c.Koukouzas Ioannis e.Zevgolis chemical 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 *** creation and sustainability of these lakes are significantly affected by the stability of the.c.rresponding *** 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 efficiently 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 decreases until the reservoir re.c.es a critical level of 10%e40%of the total height;it then increases to even more stable.c.nditions 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 Scie.c.

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.c.mpared current(2017, “post-carp” establishment) fish assemblages to historical(2002, “pre.c.rp” establishment) fish assemblages. Fish assemblages were.c.mprehensively 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 reflected by boat electrofishing and experimental gill nets. However, all indices were generally similar(P > 0.05) between the pre.c.rp and post-carp period with fish assemblages depicted using mini-fyke nets. Nonmetric multidimensional scaling analyses indicated that fish assemblages differed structurally between pre.c.rp and post-carp periods. Assemblage differe.c.s were linked to both small and large abundance.c.anges for more than 20 species. 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.c.rp 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 increased during the same *** Although not possible to conclude assemblage shifts were entirely related to bigheaded carps due to the abse.c. of an appropriate refere.c. system where.c.rps did not establish, the wide establishment of these.c.rps is one of the most pervasive.c.anges to have occurred in the lower White

关键词： Bigheaded carp Silver carp Aquatic nuisance species Fish assemblage Oxbow lake Large river

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.c.ndelo-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 inte.c.nnected *** of these microgrids in different nodes with various inte.c.n-nection technologies increases fault occurre.c. 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.c.nclusions 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