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A numerical assessment of two geometries for reducing elbow erosion

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Particuology 2020年第2期18卷 117-133页

作者： carlos antonio Ribeiro Duarte Francisco Joséde Souza Diego Nei Venturi Martin Sommerfeld Department of Engineering Federal University of Goiás-Regional Catal(a)oAv.Dr.Lamartine Pinto de Avelar1120Catal(a)oGoiásBrazil School of Mechanical Engineering Federal University of Uberl(a)ndiaAv.Joāo Naves de(A)vila2121 Bloco 5PUberl(a)ndiaMinas GeraisBrazil Multiphase Flow Systems(MPS) Otto-von-Guericke-University MagdeburgZeppelinstraβe 1D-06130 Halle(Saale)Germany

Elbows in pneumatic conveying systems are normally prone to the erosive effects of conveyed *** are a number of solutions available to reduce such damage.A widely used geometric alternative for replacing the 90°elbow and reducing erosive wear is the plugged *** option,although less commonly used,is the vortex-chamber *** both cases,the effective reduction in erosion brought about is unclear,as it strongly depends on the operating *** present study assesses relative erosion among the plugged tee,vortex-chamber elbow,and standard elbow for a dilute gas-solid multiphase flow.A numerical model is employed to predict the penetration ratio and validated using experimental data for the plugged *** are run for the standard and vortex-chamber elbows and plugged tee under the same conditions to compare the mechanics involved and the relative erosion *** analysis uses variables relating to particle-wall interactions(impact angle,impact velocity,impact frequency)to illustrate the nature of the erosive process in each pipe *** general,the geometric configurations of both the plugged tee and vortex-chamber elbow promote changes in particle dynamics that reduce the rate of *** the basis of the relative erosion of the standard elbow,the plugged tee proves to be an interesting option in cases of a low mass loading,while the vortex-chamber elbow demonstrates its erosion reduction potential for higher mass loading ***,the advantages and disadvantages of each fitting are highlighted.

关键词： Relative erosion Plugged tee Erosion reduction Pipe fitting Computational fluid dynamics

Brent *** Texas Intermediate in the US petro derivatives price formation

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Petroleum Science 2024年第1期21卷 729-739页

作者： Alejandro Almeida antonio A.Golpe Juan Manuel Martín-Alvarez Jose carlos Vides Universidad Internacional de La Rioja Department of Quantitative Methods for Economics and BusinessLa RiojaSpain University of Huelva Department of Economics and Centro de Estudios Avanzados en FisicaMatematicas y Computacion and ICEIHuelvaSpain Complutense University of Madrid Department of Applied and Structural Economics and History and ICEIMadridSpain

In this paper,we apply the spatial panel model to explore the relationship between the dynamic of two types of crude oil prices(WTI and Brent crude oil)and their refined products over *** the turbulent months of 2011,when Cushing Oklahoma had reached capacity and the crude oil export ban removal in 2015 as breakpoints,we apply this method both in the full sample and the three resultant ***,results suggest our results show that both WTI and Brent display very similar behaviour with the refined ***,when attending to each regime,results derived from the first and third regimes are quite similar to the full sample ***,during the second regime,Brent crude oil became the benchmark in the petrol market,and it influenced the distillate ***,our model can let us determine the price-setters and price-followers in the price formation mechanism through refined *** results possess important considerations to policymakers and the market participants and the price formation.

关键词： Crude oil prices Spatial panel model Refined products Price formation

The long-COVID-19 in older adults: facts and conjectures

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Neural Regeneration Research 2022年第12期17卷 2679-2681页

作者： Tino Emanuele Poloni Valentina Medici antonio Zito Arenn Faye carlos Department of Neurology-Neuropathology and Abbiategrasso Brain Bank Golgi-Cenci Foundation&Department of RehabilitationASP Golgi-Redaelli-AbbiategrassoMilanItaly Department of Neurology-Neuropathology and Abbiategrasso Brain Bank Golgi-Cenci Foundation-AbbiategrassoMilanItaly Department of Brain and Behavioral Disorders University of Pavia&IRCCS Mondino FoundationPaviaItaly

The coronavirus disease-19(COVID-19)has greatly affected the overall health of the elderly population through direct biological(infection-related)and indirect psychosocial(quarantine-and isolation-related)*** the severe form of COVID-19 most frequently targets this population,the prevalence of long-term sequelae is expected to rise consequentially in people≥65 years *** prominent neuropsychiatric consequences of COVID-19 and the cognitive frailty seen in older adults can both have a negative impact on their mental *** explore the behavioral,neurological,and psychosocial consequences of COVID-19,we conducted separate studies on different populations of older adult people residing in Lombardy-the Italian epicenter of the first pandemic wave in spring 2020.

关键词： consequences Italian COV

A quadratic linear-parabolic model-based EEG classification to detect epileptic seizures

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The Journal of Biomedical Research 2020年第3期34卷 205-212页

作者： antonio Quintero-Rincon carlos DGiano Hadj Batatia Epilepsy and Telemetry Integral Center Foundation for the Fight against Pediatric Neurological DiseaseMontaneses 2325Buenos Aires C1428AQKArgentina Computer Science Research Institute of Toulouse-National Polytechnic Institute of Toulouse University of ToulouseToulouseCedex 7 B.P.7122-31071France

The two-point central difference is a common algorithm in biological signal processing and is particularly useful in analyzing physiological *** this paper,we develop a model-based classification method to detect epileptic seizures that relies on this algorithm to filter electroencephalogram(EEG) *** underlying idea was to design an EEG filter that enhances the waveform of epileptic *** filtered signal was fitted to a quadratic linear-parabolic model using the curve fitting *** model fitting was assessed using four statistical parameters,which were used as classification features with a random forest algorithm to discriminate seizure and non-seizure *** proposed method was applied to 66 epochs from the Children Hospital Boston *** showed that the method achieved fast and accurate detection of epileptic seizures,with a92% sensitivity,96% specificity,and 94.1% accuracy.

关键词： two-point central difference curve fitting parabolic curves epilepsy electroencephalogram random forest

The coppice-with-standards silvicultural system as applied to Eucalyptus plantations-a review

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Journal of Forestry Research 2014年第2期25卷 237-248页

作者： antonio carlos FERRAZ FILHO José Roberto Soares SCOLFORO Blas MOLA-YUDEGO Departamento de Ciências Florestais Universidade Federal de Lavras (UFLA) School of Forest Sciences University of Eastern Finland (UEF)

We review the management of Eucalyptus species under a coppice-with-standards （CWS） silvicultural system. CWS management results in product diversification, permitting production of small and large scale timber from the same stand. Eucalyptus species are suitable candidates for CWS management because： there are large worldwide plantation areas, sprouting capacity is high, and eucalypts are multipur- pose species. We discuss （1） short rotation Eucalyptus coppice manage- ment for energy and pulping and （2） Eucalyptus seedling management for solid wood products. We review the literature and discuss experi- ences with Eucalyptus managed under the CWS system. We also assess projects dealing with Eucalyptus coppice management, stand density regulation, pruning, and stand and wood quality. The growth environ- ment of the standard trees （heavy competition up to the first harvest, free growth afterwards） coupled with long rotations （〉20 years） results in high quality logs for solid wood products. Early pruning should be ap- plied to enhance wood quality. We propose a system for the silvicultural management of Eucalyptus under the CWS system, elaborating on the consequences of initial planting density, site productivity, and standard tree densities as well as timing of basic silvicultural applications.

关键词： stand density regulation coppice management pruning silvicultural system stand production diversification CWS

Effect of Noisy Fitness in Real-Time Strategy Games Player Behaviour Optimisation Using Evolutionary Algorithms

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Journal of Computer Science & Technology 2012年第5期27卷 1007-1023页

作者： antonio M. Mora antonio Fernndez-Ares Juan J. Merelo Pablo García-Snchez carlos M. Fernandes Computer Architecture and Technology Department University of Granada Institute for Systems and Robotics Technical University of Lisbon

This paper investigates the performance and the results of an evolutionary algorithm （EA） specifically designed for evolving the decision engine of a program （which, in this context, is called bot） that plays Planet Wars. This game, which was chosen for the Google Artificial Intelligence Challenge in 2010, requires the bot to deal with multiple target planets, while achieving a certain degree of adaptability in order to defeat different opponents in different scenarios. The decision engine of the bot is initially based on a set of rules that have been defined after an empirical study, and a genetic algorithm （GA） is used for tuning the set of constants, weights and probabilities that those rules include, and therefore, the general behaviour of the bot. Then, the bot is supplied with the evolved decision engine and the results obtained when competing with other bots （a bot offered by Google as a sparring partner, and a scripted bot with a pre-established behaviour） are thoroughly analysed. The evaluation of the candidate solutions is based on the result of non-deterministic battles （and environmental interactions） against other bots, whose outcome depends on random draws as well as on the opponents＇ actions. Therefore, the proposed GA is dealing with a noisy fitness function. After analysing the effects of the noisy fitness, we conclude that tackling randomness via repeated combats and reevaluations reduces this effect and makes the GA a highly valuable approach for solving this problem.

关键词： real-time strategy game genetic algorithm noisy fitness player behaviour optimisation parameter adaptation

The effect of older population on public health spending:Evidence from Spain

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Health Care Science

Health Care Science 2023年第5期2卷 306-316页

作者： carlos Navarro-García antonio Sarria-Santamera Facultad de Medicina Alfonso X UniversityMadridSpain Medicine&Global Health Nazarbayev University School of MedicineAstanaKazakhstan

ackground:The gradual ageing of the population,and its effect on public spending,constitutes an urgent challenge for advanced *** this study,we analyse the effect of older people,and their health and individual characteristics,on public health ***:Using logistic regression methods,we have analysed the use of different health services and health technologies by older people in Spain,controlled for several health,socioeconomic,and other individual ***:The main factors that explain the consumption of both health services and health technology,above age,are related to the so-called need factors:self-reported health status,presence of chronic diseases,and ***:Knowing the main factors that imply greater public health spending is a topic of special interest for designing efficient health policies,in a context of growth in public health *** this way,preventive attention on the so-called need factors may be an important driver to improve the effectiveness of spending.

关键词： ageing health technology older population public health spending Spain use of health services

巴西Paraná和Bahia地区滑石矿床的地质特征与成因模式(英文)

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岩石学报 2004年第4期20卷 829-836页

作者： antonio carlos GONDIM 蒋少涌 Federal University of Parana Marechal Mallet 185/401 80540-230 Curitiba Brazil State key Laboratory for Mineral Deposits Research Department of Earth Sciences Nanjing University Nanjing 210093 China

本文总结了巴西两个最重要的滑石产地,Parana和Bahia区中滑石矿床的地质特征,并探讨了这些矿床的可能成因。巴西的滑石在世界滑石储量与产量中占有十分重要的地位。巴西Parana和Bahia区的滑石矿主要产于前寒武纪地体中。尽管该区的滑石... 详细信息

本文总结了巴西两个最重要的滑石产地,Parana和Bahia区中滑石矿床的地质特征,并探讨了这些矿床的可能成因。巴西的滑石在世界滑石储量与产量中占有十分重要的地位。巴西Parana和Bahia区的滑石矿主要产于前寒武纪地体中。尽管该区的滑石具有不同的地质产状,与变质火山岩和变质沉积岩共生的滑石最为重要。其他类型的滑石,如与镁铁质-超镁铁质岩共生的、在花岗岩与白云质大理岩接触带的、在花岗岩体中呈包体或顶垂体状的、则相对不重要。在巴西与岩浆活动有关的滑石矿化主要发生在前寒武纪(Bahia区)和白垩纪(Parana区)。滑石的成因模式主要有两类:一为与岩浆热液有关的热液交代成矿模式,另一是起源于盆地热卤水的变质流体交代成矿模式。其中后一种成因模式可用来解释巴西的大多数大型滑石矿床,同时也适用于其他地区,如中国辽宁和乌拉尔南部的滑石成矿。

关键词：滑石矿床地质特征成因模式巴西Paraná和Bahia区

Abiotic and biotic drivers of struvite solubilization in contrasting soils

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Pedosphere 2023年第6期33卷 828-837页

作者： antonio RUIZ-NAVARRO Manuel DELGADO-BAQUERIZO Concha CANO-DíAZ carlos GARCíA Felipe BASTIDA Centro de Edafologia y Biologia Aplicada del Segura Consejo Superior de Investigaciones Cientificas(CEBAS-CSIC)Department of Soil and Water ConservationEspinardoMurcia E-30100Spain ICL Specialty Fertilizers Iberia TotanaMurcia E-30850Spain Laboratorio de Biodiversidad y Funcionamiento Ecosistemico Instituto de Recursos Naturales y Agrobiologia de Sevilla(IRNAS)CSICAv.Reina Mercedes 10Sevilla E-41012Spain IRNAS-CSIC Unidad Asociada Universidad Pablo de OlavideUniversidad Pablo de Olavide(UPO)Sevilla 41013Spain Centre for Research and Development in Agrifood Systems and Sustainability(CISAS) Instituto Politecnico de Viana do Castelo(IPVC)Rua Escola Industrial e Comercial Nun'Alvares 34Viana do Castelo 4900-347Portugal

Phosphorus(P) limitation in the coming decades calls for the utilization of alternative fertilizers in agriculture. Struvite is a promising P source, but its potential role as a fertilizer is dependent on different physical, chemical, and biological properties, which are very heterogeneous in soil, complicating the prediction of the best soil conditions for its application. Here, we evaluated the solubility of struvite in soil, its redistribution into P fractions, and its potential abiotic and biotic drivers in 62 globally distributed soils with contrasting properties through an incubation assay. We found that after 40 d, about 35% of struvite P was redistributed into soil fractions more accessible to plants and microbes. Phosphorus redistribution from struvite was driven by a complex suite of soil physical, chemical, and microbial properties as well as environmental factors that varied across soils. Soil texture played a critical role in determining the redistribution of P in struvite-amended soils in soluble(H2O extraction), labile(NaHCO3 extraction), and moderately labile(NaOH extraction) *** addition, the soil solution cation concentration was one of the most important drivers of available struvite-derived P fractions. The great importance of texture and cations in determining struvite-derived P fractions in soil was contrasted with the relatively minor role of pH. At the microbial level, the number of bacterial operational taxonomic units(OTUs) from the unfertilized soils that correlated with struvite-derived P fractions was higher than that of fungi. The number of OTUs that correlated with the struvite-derived soluble P fraction was dominated by fungi, whereas the number of OTUs that correlated with the struvite-derived labile P fraction was dominated by bacteria. Overall, this study provided a predictive framework for the potential use of struvite as a P fertilizer in contrasting soils.

关键词： bacteria fungi environmental factor operational taxonomic unit phosphorus fertilizer phosphorus fraction phosphorus solubilization soil fertility soil property