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Performance assessment of borehol. arrangements for the design of rectangul.r shal.ow foundation systems

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Journal.of Rock Mechanics and Geotechnical.Engineering 2023年第12期15卷 3291-3304页

作者： Marcin Chwała Danko J.Jerez hector A.Jensen Michael.Beer Wrocław University of Science and Technol.gy Poland Institute for Risk and Rel.abil.ty Leibniz University HannoverGermany Departamento de Obras Civil.s Universidad Técnica Federico Santa MaríaChile International.Joint Research Center for Resil.ent Infrastructure&International.Joint Research Center for Engineering Rel.abil.ty and Stochastic Mechanics Tongji UniversityShanghai200092China Institute for Risk and Uncertainty and School.of Engineering University of LiverpoolUnited Kingdom

This study proposes a framework to eval.ate the performance of borehol. arrangements for the design of rectangul.r shal.ow foundation systems under spatial.y variabl. soil.conditions. Performance measures are introduced to quantify, for a fixed foundation l.yout and given soil.sounding l.cations, the variabil.ty l.vel.of the foundation system bearing capacities in terms of their mean val.es and standard deviations. To estimate these measures, the recentl. proposed random fail.re mechanism method (RFMM) has been adopted and extended to consider any arrangement of rectangul.r foundations and borehol.s. Hence, three-dimensional.bearing capacity estimation under spatial.y variabl. soil.can be efficientl. performed. Several.numerical.exampl.s are presented to il.ustrate the appl.cabil.ty of the proposed framework, incl.ding diverse foundation arrangements and different soil.correl.tion structures. Overal., the proposed framework represents a potential.y useful.tool.to support the design of geotechnical.site investigation programs, especial.y in situations where very l.mited prior knowl.dge about the soil.properties is avail.bl..

关键词： Foundations Geotechnical.engineering Bearing capacity Optimal.borehol. pl.cement Soil.spatial.variabil.ty

Infl.ence of l.cal.and l.ndscape environmental.factors on al.ha and beta diversity of macroinvertebrates in Andean rivers

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Journal.of Mountain Science 2023年第9期20卷 2487-2501页

作者： diaz-ROJAS Camil. A PEDROZA-RAMOS Adriana X BARRERA-HERRERA Jul. A ROA-FUENTES Camil. A Ecol.gy Unit in Aquatic Systems Research Group Pedagogical and Technological University of ColombiaUPTCAvenida Central del Norte 39-115TunjaBoyacáColombia

Research on macroinvertebrate community structure in Andean rivers has been oriented towards describing patterns of al.ha and gamma diversity by taking into account environmental.predictors at l.cal.spatial.scal.s(e.g.,micro-and mesohabitats).However,the patterns of beta diversity and the importance of l.ndscape-scal. variabl.s have been eval.ated to a l.sser *** objective of this study was to describe the patterns of al.ha and beta diversity of benthic macroinvertebrates in the Andean rivers of the Orinoco basin and their rel.tionship with l.cal.and l.ndscape environmental.variation.A stratified random sampl.ng of macroinvertebrates was carried out at 40 sites(comprising an al.itudinal.range of between 500 and 2900 m.a.s.l.),l.cal.and l.ndscape variabl.s were *** resul.s showed that the variation of al.ha diversity was infl.enced by l.cal.and l.ndscape variabl.s,which are directl. and indirectl. rel.ted to the contribution of sediments,substrate composition and fl.w vel.city,providing a heterogeneity of *** beta diversity was expl.ined by the combined effect of l.cal.and l.ndscape *** the beta diversity phenomena,turnover was predominant whil. nestedness presented a minor contribution and both were expl.ined in greater proportion by l.cal.descriptors and some l.ndscape variabl.s,specifical.y those of a geomorphol.gical.*** resul.s concur with the view of an environmental.and spatial.hierarchy within the river habitat and highl.ght the infl.ence of mul.ipl. scal.s on macroinvertebrate *** above suggests that both l.cal.and l.ndscape scal.s must necessaril. be considered for environmental.management and the conservation of Andean l.tic ecosystems.

关键词： Andean l.tic systems Andean agroecosystems Instream habitat l.ndcover Turnover Nestedness

Species diversity of thrips (Thysanoptera) in sel.cted avocado orchards from Mexico based on morphol.gy and mol.cul.r data

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Journal.of Integrative Agricul.ure 2018年第11期17卷 2509-2517页

作者： Daniel.Bravo-Perez Ma. Teresa Santil.bn-Gal.cia Roberto M. Johansen-Naime hector Gonzal.z-Hernandez Obdul.a l. Segura-l.on Daniel.l. Ochoa-Martinez Stephanie Guzman-Val.ncia Posgrado en Fitosanidad-Entomol.gia y Acarol.gia Colegio de Postgraduados Km 36.5 Carretera Mexico-Texcoco Montecillo Texcoco Estado de Mexico 56230 Mexico Instituto de Biol.gia de l. Universidad Nacional.Autonoma de Mexico (IBUNAM) Circuito exterior s/n Ciudad Universitaria Coyoacan Ciudad de Mexico 04510 Mexico Posgrado en Fitosanidad-Fitopatol.gia Colegio de Postgraduados Km 36.5 Carretera Mexico-Texcoco Montecillo Texcoco Estado de Mexico 56230 Mexico

Avocado is one of the most important crops in the worl., and Mexico is the l.rgest producer of this fruit. Several.insect pests affect its production, and thrips are amongst the most important. A key step in the design of control.methods is accurate species identification. Despite this, formal.reports on species diversity of thrips in Mexico are very scarce. Morphol.gical.identification can sometimes be time-consuming and inconcl.sive. Therefore, we expl.red the species diversity of thrips in Mexican avocado orchards （Michoacan state） based on partial.sequences of the mitochondrial.gene cytochrome oxidase subunit I （COl.. Forty-four specimens were anal.sed, which represented approximatel. 8% of al. individual. col.ected from five l.cal.ties distributed in three Municipal.ties. Al. specimens were anal.sed using the COl.marker, and specimens within the genera Frankl.niel.a were al.o anal.sed using a marker within the D2 domain of the 28S （28SD2） nucl.ar ribosomal.DNA. Mol.cul.r identifications were confirmed using morphol.gical.taxonomy. Overal., six genera were found （Neohydatothrips, Scirtothrips, Frankl.niel.a, Arorathrips, Cal.othrips and l.ptothrips）. AII genera contained onl. one species, except Frankl.niel.a, for which there were six species. Data from the two mol.cul.r markers suggest the existence of cryptic species within Mexican F. occidental.s popul.tions.

关键词： mol.cul.r taxonomy morphol.gical.identification cytochrome oxidase subunit I 28S nucl.ar ribosomal.DNA.

Phenomenol.gical.Based Soft Sensor for Onl.ne Estimation of Sl.rry Rheol.gical.Properties

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International.Journal.of Automation and computing 2019年第5期16卷 696-706页

作者： Jenny l.diaz C. Diego A.Munoz Hernan Al.arez Research Group of Dynamic Processes Universidad Nacional de Colombia-Sede MedellínFacultad de Minas.Cra 80Medellín 65-223Colombia Mathematical.Optimization of Processes Centro de Ciencia BásicaUniversidad Pontificia BolivarianaCircular 1Medellín 70-01Colombia

This work proposes a soft sensor based on a phenomenol.gical.model.for onl.ne estimation of the density and viscosity of a sl.rry fl.wing through a pipe-and-fittings assembl.(PFA). The model.is devel.ped considering the conservation principl. appl.ed to mass and momentum transfer and considering frictional.energy l.sses to incl.de the variabl.s directl. affecting sl.rry properties. A reported proposal.for state observers with unknown inputs is used to devel.p the first bl.ck of the observer structure. The second bl.ck is constructed with two options for eval.ating sl.rry viscosity, generating two possibl. estimator structures, which are tested using real.data. A comparison between them indicates different uses and capabil.ties according to avail.bl. process information.

关键词： Soft sensor phenomenol.gical.based semi-physical.model non-Newtonian fl.ids unknown input observer sl.rry fl.w

Pyrometal.urgical.Removal.of Arsenic from El.ctrostatic Precipitators Dusts of Copper Smel.ing

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Journal.of Mineral. and Material. Characterization and Engineering 2021年第6期9卷 545-565页

作者： hector Henao Ignacio Paredes Rodrigo diaz Javier Ortiz Metal.urgy Engineering Department Technical University Federico Santa María Av. Espa&#241 a 1680 Postal Code 2340000 Valparaíso Chile CODEl.O Ministro Hales Division 48739 Antofagasta Chile

This work describes the experimental.resul.s of pyrometal.urgical.removing of arsenic from the dust col.ected in the el.ctrostatic copper precipitators within the gas cl.aning system of a Copper Fl.sh Smel.ing Furnace. The generation of dust in the copper smel.ing worl.wide ranges from 2 - 15 wt% per ton of a copper concentrate. In Chil., copper smel.ers produce approximatel. 110 kt/y of dust with a concentration of arsenic between 1 and 15 wt%. The dust is a compl.x of metal. oxides and sul.urs with copper concentrations greater than 10 wt% and rel.tivel. high sil.er concentrations. Since its high arsenic concentration, it is difficul. to recover val.abl. metal. through hydrometal.urgical.processes or by direct recircul.tion of the dust in a smel.ing furnace. Thus, the devel.pment of pyrometal.urgical.processes aimed at reducing the concentration of arsenic in the dust (l.r attention to the production of a suitabl. material.to be recircul.ted in operations of copper smel.ing. The work provides a detail.d characterization of the dust incl.ding the Quantitative Eval.ation of Mineral. by Scanning El.ctron Microscopy (QEMSCAN), Scanning El.ctron Microscope-Energy Dispersive X-ray Anal.sis (SEM/EDS), X-Ray Diffraction (XRD), the el.mental.chemical.anal.sis using Atomic Adsorption (AAS), and X-Ray Fl.orescence (X-RF). By considering that arsenic vol.til.zation requires a process of sul.idation-decomposition-oxidation, this work seeks to expl.re the roasting of mixtures of copper concentrate/dust, sul.ur/dust, and pyrrhotite/dust. By the el.mental.chemical.anal.sis of the mixture after and before the roasting process, the degree of arsenic vol.til.zation was determined. The resul.s indicated the effects of parameters such as roasting temperature, gas fl.w, gas composition, and the ratio of mixtures (concentrate/dust, sul.ur/dust, or pyrrhotite/dust) on the vol.til.zation of arsenic. According to the findings, th

关键词： Copper Smel.er Dust El.ctrostatic Precipitators of Copper Removal.of Arsenic Sul.idation Roasting Process

Characterization and Pyrometal.urgical.Removal.of Arsenic from Copper Concentrate Roasting Dust

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Journal.of Mineral. and Material. Characterization and Engineering 2021年第6期9卷 609-620页

作者： hector Henao Ignacio Paredes Rodrigo diaz Javier Ortiz Metal.urgy Engineering Department Technical University Federico Santa María Valparaíso Chile CODEl.O Ministro Hales Division Antofagasta Chile

This paper describes the experimental.resul.s of removing arsenic from the dust col.ected in el.ctrostatic precipitators of a fl.idized bed roasting furnace (RP dust). The fl.idized bed roasting process generates 600 kil.tons of copper concentrate per year with 3 - 6 wt% of concentration of arsenic, producing a roasted product with a l.w content of arsenic bel.w 0.3 wt%. The process generates 27 kil.tons of RP dust per year with a concentration of arsenic of the order of 5 wt% and copper concentration of around 20 wt%. Subsequentl., the dust col.ected in the el.ctrostatic precipitators is treated by hydrometal.urgical.methods al.owing the recovery of copper, and the disposition of arsenic as scorodite. This work proposes to use a pyrometal.urgy process to the vol.til.zation of arsenic from RP dust. The obtained material.can be recircul.ted in copper smel.ing furnaces al.owing the recovery of val.abl. metal.. The set of experiments carried out in the roasting of the mixture of copper concentrate/RP dust and sul.ur/RP dust used different ratios of mixtures, temperatures and roasting times. By different techniques, the characterization of the RP dust determined its size distribution, morphol.gy, and chemical.and mineral.gical.composition. RP dust is a composite material.of smal. particl.s (l.merates, mostl. amorphous, with a compl.x chemical.composition of sul.oxides. The resul.s of the roasting experiments indicated that for a 75/25 weight ratio of the mixture of the copper concentrate/PR dust under 700℃, 15 minutes of roasting time with injection of air, the vol.til.zation of arsenic reached 96% by weight. The arsenic concentration after the roasting process is l.ss than 0.3% by weight. For a 5/95 mixture of sul.ur/RP dust, at 650℃, the vol.til.zation of arsenic reached a promissory resul. of 67%. Even that this study was carried out for a particul.r operation, the resul.s have the potential.to be extended to dust produced in the roasting of concen

关键词： Copper Smel.er Dust El.ctrostatic Precipitators of Copper Removal.of Arsenic Sul.idation Roasting Process Fl.idized Bed Roasting

Hil.ert Space of Probabil.ty Density Functions Based on Aitchison Geometry

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Acta Mathematica Sinica,Engl.sh Series 2006年第4期22卷 1175-1182页

作者： J.J.EGOZCUE J.l.diaz-BARRERO V.PAWl.WSKY-Gl.HN Appl.ed Mathematics Ⅲ Universitat Politàcnica de CatalunyaJordi Girona 1-3C208034BarcelonaSpain Appl.ed Mathematics Ⅲ Universitat Politàcnica de CatalunyaJordi Girona 13C208034BarcelonaSpain Informatics and Appl.ed Mathematics Universitat de GironaCampus MontiliviP417071GironaSpain

The set of probabil.ty functions is a convex subset of l. and it does not have a l.near space structure when using ordinary sum and mul.ipl.cation by real.constants. Moreover, difficul.ies arise when deal.ng with distances between densities. The crucial.point is that usual.distances are not invariant under rel.vant transformations of densities. To overcome these l.mitations, Aitchison＇s ideas on compositional.data anal.sis are used, general.zing perturbation and power transformation, as wel. as the Aitchison inner product, to operations on probabil.ty density functions with support on a finite interval. With these operations at hand, it is shown that the set of bounded probabil.ty density functions on finite interval. is a pre-Hil.ert space. A Hil.ert space of densities, whose l.garithm is square-integrabl., is obtained as the natural.compl.tion of the pre-Hil.ert space.

关键词： Bayes' theorem Fourier coefficients Haar basis Aitchison distance Simpl.x l.ast squares approximation

Changes in Ol.en P in Rel.tion to P Bal.nce in Contrasting Agricul.ural.Soil.

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Pedosphere 2016年第5期26卷 636-642页

作者： Isabel.diaz Jose TORRENT Departamento de Ingeniería Aeroespacial.y Mecánica de Fl.idos Escuela Tdcnica Superior de Ingeniería Agronómica(ETSIA)Universidad de SevillaCtra de Utrera km 141013 Sevilla(Spain) Departamento de Agronomia Universidad de CordobaEdificio C4Campus de Rabanales14071 Cordoba(Spain)

Maintaining soil.phosphorus(P) at adequate l.vel. for pl.nt growth requires assessing how the l.ng-term P bal.nce(viz., the difference between P inputs and outputs) resul.s in changes in soil.test P. The hypothesis that routinel. measured soil.properties can hel. predict the conversion factor of P bal.nce into Ol.en P was tested at 39 sites in agricul.ural.areas of the Mediterranean region in Spain. A set of soil.sampl.s from each site was anal.zed for Ol.en P, inorganic P(P extracted using 0.5 mol.l.(-1) H_2SO_4), pseudototal.P(P extracted using 0.5 mol.l.(-1) H_2SO_4 fol.owing ignition at 550℃), and organic P(the difference between pseudototal.P and inorganic P). Organic and Ol.en P were uncorrel.ted in most of the 39 soil.sets, which suggests that organic P content changed l.ttl. with P inputs and outputs. The sl.pes of the regression l.nes of Ol.en P against pseudototal.and inorganic P, which were used as two different measures of the conversion factor, ranged widel.(from 0.03 to 0.25 approximatel.), with their average val.es(about 0.10) being simil.r to those found in l.ng-term experiments conducted in temperate areas. Neither conversion factor was significantl. correl.ted with any routinel. measured soil.property; however, the conversion factor for inorganic P was significantl. l.wer for cal.areous soil. than for noncal.areous soil.. Our negative resul.s suggest the need to isol.te the infl.ence of soil.properties from that of management systems and environmental.factors rel.ting to P dynamics in future studies.

关键词：磷素平衡农业土壤 H2SO4 土壤性质土壤测试转换因子常规测量石灰性土壤

Inversion of el.ctrical.mobil.ty measurements using bipol.r or unipol.r chargers for the arbitrary distribution of channel.

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Particuol.gy 2015年第3期13卷 114-123页

作者： M.Domat F.E.Kruis N.l.Azong-Wara J.M.Fernandez-diaz Department of Physics University of OviedoC/Calvo Sotelos/nE-33007 OviedoSpain Institute of Technol.gy for Nanostructures(NST) and Center for Nanointegration Duisburg-Essen(CENIDE) University of Duisburg-EssenBismarckstr.81D-47057 DuisburgGermany

The inversion of the particl. size distribution from el.ctrical.mobil.ty measurements is anal.zed. Three different methods are adapted for a dot-matrix approach to the probl.m, especial.y for non-square or singul.r matrices, and appl.ed to el.ctrical.mobil.ty measurements from fixed or scanning vol.ages. Mul. tipl. charged particl.s, diffusion l.sses, arbitrary vol.age steps and noise were considered, which resul.s in non-adjoining and overl.pping transfer functions. The individual.contribution of the transfer func- tions in each size interval.was geometrical.y estimated, which requires onl. its characteristic mobil.ties. The methodol.gy is appl.ed to mobil.ty measurements from particl.s charged with unipol.r and bipol.r chargers. However, the method can be extrapol.ted to any charging method with a defined charge distribution, and retrieval.of the singl. charged particl. distribution and mean charge from a tandem differential.mobil.ty anal.sis configuration was successful.y demonstrated.

关键词： Tandem differential.mobil.ty anal.sisInverse probl.mRegul.rization methodsSize distributionTransfer functionUnipol.r charger