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Assessment of compressive strength of jet grouting by machine learning

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第1期16卷 102-111页

作者： Esteban Diaz Edgar Leonardo Salamanca-Medina Roberto Tomas departamento de ingeniería Civil Escuela Politécnica SuperiorUniversidad de AlicanteP.O.Box 99E-03080AlicanteSpain

Jet grouting is one of the most popular soil improvement techniques,but its design usually involves great uncertainties that can lead to economic cost overruns in construction *** high dispersion in the properties of the improved material leads to designers assuming a conservative,arbitrary and unjustified strength,which is even sometimes subjected to the results of the test *** present paper presents an approach for prediction of the uniaxial compressive strength(UCS)of jet grouting columns based on the analysis of several machine learning algorithms on a database of 854 results mainly collected from different research *** selected machine learning model(extremely randomized trees)relates the soil type and various parameters of the technique to the value of the compressive *** the complex mechanism that surrounds the jet grouting process,evidenced by the high dispersion and low correlation of the variables studied,the trained model allows to optimally predict the values of compressive strength with a significant improvement with respect to the existing ***,this work proposes for the first time a reliable and easily applicable approach for estimation of the compressive strength of jet grouting columns.

关键词： Jet grouting Ground improvement Compressive strength Machine learning

Discretized Miller approach to assess effects on boundary layer ingestion induced distortion

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Chinese Journal of Aeronautics 2017年第1期30卷 235-248页

作者： Esteban Valencia Víctor Hidalgo devaiah Nalianda Laskaridis Panagiotis Riti Singh departamento de ingeniería Mecánica Facultad de Ingeniería Mecánica Escuela Politécnica Nacional Ladron de Guevara E11-253 Quito 17-01-2759 Ecuador School of Engineering Cranfield University Bedford MK430AL United Kingdom

The performance of propulsion configurations with boundary layer ingestion（BLI） is affected to a large extent by the level of distortion in the inlet flow field. Through flow methods and parallel compressor have been used in the past to calculate the effects of this aerodynamic integration issue on the fan performance; however high-fidelity through flow methods are computationally expensive, which limits their use at preliminary design stage. On the other hand, parallel compressor has been developed to assess only circumferential distortion. This paper introduces a discretized semi-empirical performance method, which uses empirical correlations for blade and performance calculations. This tool discretizes the inlet region in radial and circumferential directions enabling the assessment of deterioration in fan performance caused by the combined effect of both distortion patterns. This paper initially studies the accuracy and suitability of the semiempirical discretized method by comparing its predictions with CFD and experimental data for a baseline case working under distorted and undistorted conditions. Then a test case is examined,which corresponds to the propulsor fan of a distributed propulsion system with BLI. The results obtained from the validation study show a good agreement with the experimental and CFD results under design point conditions.

关键词： BLI Correlations Distortion Embedded propulsors Empirical Mean-line analysis Turbomachinery

Endophytes versus biotrophic and necrotrophic pathogens—are fungal lifestyles evolutionarily stable traits?

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Fungal Diversity 2013年第3期60卷 125-135页

作者： Luis delaye Graciela García-Guzmán Martin Heil departamento de ingeniería Genética Centro de Investigación y de Estudios Avanzados(CINVESTAV)IrapuatoGuanajuatoMexico departamento de Ecología Evolutiva Instituto de EcologíaUNAMMéxico CityMexico

Endophytes infect living plant tissues without causing symptoms of ***,many of them contribute to the resistance phenotype of their ***,fungal endophytes are generally closely related to plant pathogens,fungi that either develop within living host tissue(biotrophic fungi)or that kill the host cells and then live in the dead tissue(necrotrophic fungi).We adopted a phylogenetic approach to investigate whether these strategies represent evolutionarily stable lifestyles and to elucidate their general phylogenetic *** analysed 163 fungal strains for which we found information on the sequence of the 5.8S rRNA gene and the flanking internal transcribed spacer regions,the identity of the host plant and the concrete phenotypic outcome of the infection.A Maximum-Likelihood analysis combined with ancestral character mapping by maximum parsimony revealed that some fungal lineages had switched multiple times between a necrotrophic and an endophytic *** character mapping indicated a minimum of four changes from an endophytic to a necrotrophic lifestyle,four changes in the opposite direction and eight changes among these lifestyles for which the direction could not be determined *** contrast,biotrophs formed five clusters that did not contain necrotrophs or *** biotrophy evolves there is apparently no regression to one of the other two *** conclude that biotrophy usually represents a derived and evolutionarily stable trait,whereas fungi easily can switch between an endophytic and necrotrophic lifestyle at the evolutionary and even the ecological *** experimental studies should focus on the environmental or genetic changes that cause the rapid switches between these two phenotypically different lifestyles.

关键词： Disease expression Fungi Plant pathogens Phylogenetic effects

Monoclonal antibodies and aptamers:The future therapeutics for Alzheimer’s disease

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Acta Pharmaceutica Sinica B 2024年第7期14卷 2795-2814页

作者： Alvaro Barrera-Ocampo Facultad de ingenierıa Diseno y Ciencias AplicadasDepartamento de Ciencias Farmaceuticas y QuimicasGrupo NaturaUniversidad IcesiCali 760031Colombia

Alzheimer’s disease(AD)is considered the most common and prevalent form of dementia of adult-onset with characteristic progressive impairment in cognition and *** cure for AD has not been found yet and the treatments available until recently were only *** of multidisciplinary approaches and efforts made by pharmaceutical companies,it was only in the past two years that new drugs were approved for the treatment of the *** beta(Aβ)immunotherapy is at the core of this therapy,which is one of the most innovative approaches looking to change the course of *** technology is based on synthetic peptides or monoclonal antibodies(mAb)to reduce Ab levels in the brain and slow down the advance of ***,this article reviews the state of the art about AD neuropathogenesis,the traditional pharmacologic treatment,as well as the modern active and passive immunization describing approved drugs,and drug prototypes currently under investigation in different clinical *** addition,future perspectives on immunotherapeutic strategies for AD and the rise of the aptamer technology as a non-immunogenic alternative to curb the disease progression are discussed.

关键词： Aβ Monoclonal antibody DNA aptamers Cognitive impairment Alzheimer’s disease Clinical trials Immunotherapy Machine learning

Dynamics of mediterranean pine forests reforested after fires

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Journal of Forestry Research 2023年第2期34卷 345-354页

作者： Álvaro Enríquez-de-Salamanca departamento de Biodiversidad Ecología y EvoluciónFacultad de Ciencias BiológicasUniversidad Complutense de MadridMadridSpain Draba ingeniería y Consultoría Medioambiental San Lorenzo de El EscorialSpain

Forest fires are frequent under a Mediterranean climate and have shaped the landscape of the region but are currently altered by human action and climate *** have historically conditioned the presence of pine forests,depending on severity and forest *** of Mediterranean pine forests is not always successful,and a transition to shrublands or stands of resprouting species can occur,even after *** study analyses vegetation changes in two Mediterranean pine forests after severe fires and both *** pines had difficulty to regenerate,even despite post-fire *** problem is the difficulty of young seedlings to survive,possibly due to increased summer *** are greater in pine species at the limit of their ecological tolerance:Pinus pinea had a much better recovery success while *** and *** virtually *** pinaster had intermediate results but recovery was generally poor.A transition has taken place in many burnt areas to scrubland or to thickets of the resprouting Quercus rotundifolia,although it is not possible to know whether they will evolve into forests or remain in a sub climatic *** species may increase fire severity but facilitates post-fire ***-fire recovery difficulties are closely linked to issues of natural *** could initiate the disappearance of pine forests,but even in the absence of fire they may disappear in the long-term due to the lack of *** is needed to increase the resilience of these forests,ensuring natural regeneration,and incorporating resprouting species in the understorey.

关键词： Mediterranean region Pine forests Post-fi re recovery Vegetation dynamics Wildfi re transitions

Modelling the impacts of cover crop management strategies on the water use,carbon exchange and yield of olive orchards

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Journal of Forestry Research 2023年第1期34卷 283-295页

作者： Alvaro López-Bernal Omar García-Tejera Luca Testi Francisco J.Villalobos departamento de Agronomía Universidad de CórdobaCampus de RabanalesEdifi cio C414071 CórdobaSpain departamento de ingeniería Agraria Y del Medio Natural Universidad de La LagunaCarretera General de Geneto 238200 San Cristóbal de La LagunaSpain Instituto de Agricultura Sostenible(IAS) Consejo Superior de Investigaciones Científi cas(CSIC)Av.Menéndez Pidal S/N14080 CórdobaSpain

Cover crops have long been proposed as an alternative soil management for minimizing erosion rates in olive stands while providing additional ecosystem ***,the trade-off between these benefits and the competition for water with the trees makes the definition of optimal management practices a challenging task in semiarid *** work presents an improved version of OliveCan,a process-based simulation model of olive orchards that now can simulate the main impacts of cover crops on the water and carbon balances of olive *** simple in its formulation,the new model components were developed to deal with different cover crop management *** are presented for simulation runs of a traditional olive orchard in the conditions of southern Spain,evaluating the effects of different widths for the strip occupied by the cover crop(Fcc)and two contrasting mowing *** revealed that high Fccresulted in lower olive yields,but only when mowing was applied at the end of *** this regard,late mowing and high Fccwas associated with lower soil water content from spring to summer,coinciding with olive flowering and the earlier stages of fruit *** also negatively correlated with surface runoff irrespective of the mowing *** the other hand,net ecosystem productivity(NEP)was substantially affected by both Fccand mowing *** simulations under future climate scenarios comparing the same management alternatives are also presented,showing substantial yield reductions by the end of the century and minor or negligible changes in NEP and seasonal runoff.

关键词： Carbon exchange Cover crops Crop modelling Evapotranspiration Olea europaea L

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Biocomposites Based on Thermoplastic Starch and Granite Sand Quarry Waste

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Journal of Renewable Materials 2019年第4期7卷 393-402页

作者： María G.Passaretti Mario D.Ninago Cecilia I.Paulo Horacio A.Petit Edgardo F.Irassarc Daniel A.Vega Marcelo A.Villar Olivia V.López Planta Piloto de ingeniería Química PLAPIQUI(UNS-CONICET)Camino"La Carrindanga"Km 7Bahía Blanca8000Buenos AiresArgentina departamento de ingeniería Química Universidad Nacional del Sur(UNS)Bahía Blanca8000Buenos AiresArgentina Facultad de Ciencias Aplicadas a la Industria(FCAI) Universidad Nacional de Cuyo(UNCuyo)Bernardo de Irigoyen 375San Rafael5600MendozaArgentina Consejo Nacional de Investigaciones Científicas y Técnicas(CONICET) Godoy Cruz 2290Ciudad Autónoma de Buenos AiresC1425FQBBuenos AiresArgentina Facultad de ingeniería Universidad Nacional del Centro de la Provincia de Buenos Aires(UNCPBA).Centro de Investigaciones en Física e IngenieríaCIFICEN(UNCPBA-CICPBA-CONICET)7400OlavarríaArgentina Instituto de Física del Sur IFISUR(UNS-CONICET)Bahía Blanca8000Argentina

Granite stone is a by-product of the rock crushing *** industrial waste in powder form that causes health problems and environmental *** particles fraction can be used as a partial replacement of sand in concrete *** this work,an alternative exploitation of this waste fraction is *** sand(GS)with particles mean size of ~1μm was employed as thermoplastic starch(TPS)filler at different *** were obtained by melt-mixing and thermo-compression,achieving translucent and easy to handle films.A good GS dispersion within the matrix was evidenced by *** presence induced a shift of starch’s melting point to higher values and a better thermal *** UV absorption capacity was increased ~90% by GS *** increment in TPS Young’s modulus and maximum tensile stress of 5 and 3 times,respectively was observed by adding 5%w/w GS.

关键词： Thermoplastic starch granite sand melt processing final properties

Kinetic behaviour of commercial catalysts for methane reforming in ethanol steam reforming process

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Journal of Energy Chemistry 2014年第5期23卷 639-644页

作者： Jorge Vicente Javier Erea Martin Olazar Pedro L.Benito Javier Bilbao Ana G.Gayubo departamento de ingeniería Química Universidad del País Vasco UPV/EHU Apartado 644 48080 Bilbao Spain departamento de ingeniería Minera y Metalúrgica y Ciencia de los Materiales Universidad del País Vasco UPV/EHUNieves Cano 12 01006 Vitoria-Gasteiz Spain

Ethanol steam reforming has been studied in a fluidized bed （in order to ensure bed isothermicity） on commercial catalysts for methane reforming. The results allow analyzing the effect of temperature （in 300-700℃ range）, and both metal and support nature on the reaction indices （ethanol conversion, yields and selectivities to H2 and byproducts （CO2, CO, CH4 and C2H4O））. Special attention has been paid to catalysts＇ stability by comparing the evolution of the reaction indices with time on stream at 500°C （minimum CO formation） and 700℃ （minimum deactivation by coke deposition）. Although they provide a slightly lower H2 yield, the results evidence a good behaviour of Ni based catalysts, indicating that they are an interesting alternative of more expensive Rh based ones.

关键词： ethanol steam reforming hydrogen commercial catalyst selectivity deactivation

Application of the extended Fourier amplitude sensitivity testing(FAST)method to inflated,axial stretched,and residually stressed cylinders

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Applied Mathematics and Mechanics(English Edition) 2023年第12期44卷 2139-2162页

作者： H.ASGHARI H.TOPOL B.MARKERT J.MERODIO departamento de Matemática Aplicada a las TIC ETS de Ingenier a de Sistemas InformáticosUniversidad Politécnica de MadridMadrid 28031Spain Institute of General Mechanics RWTH Aachen UniversityAachen 52062Germany

This paper is dedicated to applying the Fourier amplitude sensitivity test(FAST)method to the problem of mixed extension and inflation of a circular cylindrical tube in the presence of residual *** metafunctions and the Ishigami function are considered in the sensitivity analysis(SA).The effects of the input variables on the output variables are investigated,and the most important parameters of the system under the applied pressure and axial force such as the axial stretch and the azimuthal stretch are determined.

关键词： sensitivity analysis(SA) Fourier amplitude sensitivity test(FAST)method cylindrical inflation nonlinear elasticity