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

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International Journal of coal Science & 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 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 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

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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 Sciences 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 chiral bands in the same nucleus,the coexistence of octupole correlations and nuclear chirality,and the coexistence 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 calculations showed that nuclear chirality can persist.

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

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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

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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 nuclei *** the ZOrA-ccSD(T)/QZP-ZOrA theoretical model,atomic ionization energies and bond lengths,harmonic vibrational frequencies,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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combining video and GPS-tracking to study the spatial foraging distribution of a single-prey loading seabird

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Avian research 2024年第3期15卷 316-325页

作者： ruben c.Fijn Wouter courtens Bas W.r.engels emiel e.van Loon Judy Shamoun-Baranes Waardenburg ecology Deparonent of Bird EcologyCulemborgthe Netherlands University of Amsterdam Insnitute for Biodiversity and Ecoasystem DymaomicsAmsterdamthe Netherlands research Insitute for Nature and Forest(INBO) BrusselsBcgium

Seabirds are valuable indicators of marine ecosystem processes and studying seabird diets can shed light on natural or human-induced variability in food-web *** single-prey loading seabird species such as terns have the potential to act as visual sentinels of prey availability ***,obtaining diet information from remote bird colonies is often challenging and time *** this pilot study we present a novel approach to combine two established methods to study seabird foraging ecology,providing a powerful and cost-effective tool to study the distribution of prey items available to *** combined GPS tracking data of Sandwich Terns(Thalasseus sandvicensis)with prey-observations from a hide in 2012 and 2013,and from semicontinuously recorded camera footage in *** doing so,we identified 115 approximate catch locations of prey(86 herring/sprat clupeidae,29 sandeel Ammodytidae).combining GPS-data and prey observations yielded detailed knowledge on the movements and chick diets of tracked birds as well as the spatial origin and lengths of captured prey *** catch distances of both clupeidae and Ammodytidae resulted in deliveries of larger prey items and thus higher energy yield per trip,but also a higher energy expenditure per *** discuss the limitations and potential of our methodological approach to study foraging energetics during chick-provisioning of seabirds that carry prey items visible in their beaks.

关键词： Diet Digitalfilm Geo-referencing Non-invasive monitoring Provisioning Sandwich Tern Thalasseus sandvicensis

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Decision and coordination of an e-commerce Supply chain considering returns and Network externalities

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Journal of Systems Science 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.cheng Dexia Wang School of Public Finance and Taxation Shandong University of Finance and Economicsjinan 250014China bschool of Management Science 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-commerce 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“commission 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 can improve ecSc’s profitability,while a high return rate hurts its economic performance.

关键词： e-commerce supply chain coordination mechanism network externalities return products

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convergent plate boundary environments for formation of≥3800 Ma mafic-ultramafic assemblages(Isua area,Greenland):Implications for early global geodynamics

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Geoscience Frontiers 2024年第3期15卷 119-136页

作者： Allen P.Nutman clark r.L.Friend Vickie c.Bennett School of earth Atmospheric and Life SciencesUniversity of WollongongWollongongNSW 2522Australia Glendale TiddingtonOxon OX92LQUK research School of earth Sciences Australian National UniversityCanberraACT 2601Australia

In the gneiss terrane on the south side of the eoarchean Isua supracrustal belt,ultramafic rocks with relict abyssal peridotite mineralogy(Bennett et al.,2002;Friend et al.,2002;Nutman et al.,2007;rollinson,2007;van de Löcht et al.,2020),layered gabbros with cumulate ultramafic rocks,basalts and associated siliceous sedimentary rocks were tectonically-imbricated,prior to and during intrusion of ca.3800 Ma *** with3800 Ma basalts in the Outer Arc Group of the nearby Isua supracrustal belt,the composition of all these mafic rocks(e.g.,Th-Hf-Nb systematics,high Th/Yb,Ba/Nb,Ba/Yb ratios and negative Nb and Ti anomalies)shows affinity with modern suprasubduction rocks whose genesis involved fluid fluxing of the upper ***,the majority of these samples have Ba/Nb and Ba/Yb values less than in modern island arc magmas,but similar to many backarc basin magmas(e.g.,Pearce and Stern,2006).It is unknown whether these ca.3800 Ma mafic rocks are,(i)arc rocks where the Ba/Nb and Ba/Yb signatures reflect lower surficial Ba in eoarchean oceanic settings,or(ii)in direct comparison with Phanerozoic suites,these signatures reflect a back-arc setting with interplay between fluid fluxing and decompressional *** tectonic intercalation of upper mantle with lower and upper crustal rocks,combined with the fluid-fluxing influences seen in chemistry of all the mafic rocks is best accommodated in a compressional eoarchean convergent plate boundary setting within a mobile-lid *** stagnant lid scenarios of crust formation,if operative,must have co-existed or alternated with mobile-lid regimes by 3800 Ma.

关键词： eoarchean Fluid-fluxing Plate tectonics Suprasubduction crustal evolution

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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 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 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 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 reaches a critical level of 10%e40%of the total height;it then increases 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

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comparison of methods for deriving phenotypes from incomplete observation data with an application to age at puberty in dairy cattle

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Journal of Animal Science and Biotechnology 2024年第2期15卷 535-545页

作者： Melissa A.Stephen chris r.Burke Jennie e.Pryce Nicole M.Steele Peter r.Amer Susanne Meier claire V.c.Phyn Dorian J.Garrick DairyNZ Ltd 605 Ruakura RoadHamilton 3240New Zealand AL rae centre for Genetics and Breeding-Massey University RuakuraHamilton 3214New Zealand Agriculture Victoria research AgriBioCentre for AgriBioscienceBundooraVictoria 3083Australia School of Applied Systems Biology La Trobe UniversityBundooraVictoria 3083Australia AbacusBio DunedinNew Zealand

Background Many phenotypes in animal breeding are derived from incomplete measures,especially if they are challenging or expensive to measure *** include time-dependent traits such as reproductive status,or *** measures for these traits result in phenotypes that are subject to left-,interval-and rightcensoring,where phenotypes are only known to fall below an upper bound,between a lower and upper bound,or above a lower bound *** we compare three methods for deriving phenotypes from incomplete data using age at first elevation(>1 ng/mL)in blood plasma progesterone(AGeP4),which generally coincides with onset of puberty,as an example *** We produced AGeP4 phenotypes from three blood samples collected at about 30-day intervals from approximately 5,000 Holstein–Friesian or Holstein–Friesian×Jersey cross-bred dairy heifers managed in 54 seasonal-calving,pasture-based herds in New *** used these actual data to simulate 7 different visit scenarios,increasing the extent of censoring by disregarding data from one or two of the three *** methods for deriving phenotypes from these data were explored:1)ordinal categorical variables which were analysed using categorical threshold analysis;2)continuous variables,with a penalty of 31 d assigned to right-censored phenotypes;and 3)continuous variables,sampled from within a lower and upper bound using a data augmentation *** credibility intervals for heritability estimations overlapped across all methods and visit scenarios,but estimated heritabilities tended to be higher when left censoring was *** sires with at least 5 daughters,the correlations between estimated breeding values(eBVs)from our three-visit scenario and each reduced data scenario varied by method,ranging from 0.65 to *** estimated breed effects also varied by method,but breed differences were smaller as phenotype censoring *** Our results indicate that using

关键词： cattle Gibbs sampler Markov-chain Monte carlo(McMc) Puberty

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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 Science

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 ring the post-carp period as reflected 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 depicted 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 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-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 increased 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 species Fish assemblage Oxbow lake Large river

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