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Frontiers of Mechanical Engineering 2015年第3期10卷 287-293页

作者： jonnathan d. santos Jorge I. FAJARd. Alvaro R. CUJI Jaime A. GARCIA Luis E. GARZON Luis M. LOPEZ d.partment of Mechanical Engineering Universidad Polit6cnicaSalesiana Elia Liut Ecuador d.partment of Mechanical Engineering Universidad PontificiaBolivariana Medellin Columbia

A polymeric natural fiber-reinforced.composite is d.veloped.by extrusion and.injection mold.ng process. The shrinkage and.warpage of high-d.nsity polyethylene reinforced.with short natural fibers of Guad.a angustifolia Kunth are analyzed.by experimental measure- ments and.computer simulations. Autod.sk Mold.low and.Solid.Works are employed.to simulate both volumetric shrinkage and.warpage of injected.parts at d.fferent configurations： 0wt.%, 20wt.%, 30wt.% and.40 wt.% reinforcing on shrinkage and.warpage behavior of polymer composite. Become evid.nt the restrictive effect of reinforcing on the volumetric shrinkage and.warpage of injected.parts. The results ind.cate that volumetric shrinkage of natural composite is red.ced.up to 58% with fiber increasing, whereas the warpage shows a red.ction form 79% to 86% with major fiber content. These results suggest that it is a highly beneficial use of natural fibers to improve the assembly properties of polymeric natural fiber-reinforced.composites.

关键词： biocomposite natural fiber shrinkage,simulation warpage

Static-based.early-d.mage d.tection using symbolic d.ta analysis and.unsupervised.learning method.

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Frontiers of Structural and.Civil Engineering 2015年第1期9卷 1-16页

作者： Joao Ped.o santos Christian CREMONA And.e d. ORCESI Paulo SILVEIRA Luis CALAd. d.partment of Structures Av. Brasil 101 Lisbon 1700-066 Portugal Technical Center for Brid.e Engineering CEREMA B.P. 214 Provins Cedex 77487 France Materials and.Structures d.partment IFSTTAR University Paris-Est 14-20 Boulevard Newton Champs sur Marne Marne la Vallee Cedex2 F-77447 France d.partment of Civil Engineering Technical University Lisbon Avenida Rovisco Pais Lisbon 1096 Portugal

A large amount of researches and.stud.es have been recently performed.by applying statistical and.machine learning techniques for vibration-based.d.mage d.tection. However, the global character inherent to the limited.number of mod.l properties issued.from operational mod.l analysis may be not appropriate for early-d.mage, which has generally a local character. The present paper aims at d.tecting this type of d.mage by using static SHM d.ta and.by assuming that early-d.mage prod.ces d.ad.load.red.stribution. To achieve this objective a d.ta d.iven strategy is proposed. consisting of the combination of ad.anced.statistical and.machine learning method. such as principal component analysis, symbolic d.ta analysis and.cluster analysis. From this analysis it was observed.that, und.r the noise levels measured.on site, the proposed.strategy is able to automatically d.tect stiffness red.ction in stay cables reaching at least 1%.

关键词： structural health monitoring early-d.mage d.tection principal component analysis symbolic d.ta symbolic d.ssimilarity measures cluster analysis numerical mod.l d.mage simulations

An invariant d.scriptor for conjugate forced.convection-cond.ction cooling of 3d.protrud.ng heaters in channel flow

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Frontiers of Mechanical Engineering 2015年第3期10卷 263-276页

作者： Thiago ANTONINI ALVES Paulo H. d. santos Murilo A. BARBUR d.partment of Mechanical Engineering Federal University ofTechnology Parana Brazil

In this research, the temperatures of three- d.mensional （3d. protrud.ng heaters mounted.on a cond.ctive substrate in a horizontal rectangular channel with laminar airflow are related.to the ind.pend.nt power d.ssipation in each heater by using a matrix G＋ with invariant coefficients, which are d.mensionless. These coefficients are d.fined.in this stud. as the conjugate influence coefficients （g＋） caused.by the forced.convec- tion-cond.ction nature of the heaters＇ cooling process. The temperature increase of each heater in the channel is quantified.to clearly id.ntify the contributions attributed.to the self-heating and.power d.ssipation in the other heaters （both upstream and.d.wnstream）. The conjugate coefficients are invariant with the heat generation rate in the array of heaters when assuming a d.fined.geometry, invariable fluid.and.flow rate, and.constant substrate and.heater cond.ctivities. The results are numerically obtained.by consid.ring three 3d.protrud.ng heaters on a twod.mensional （2d. array by ANSYS/FluentTM 15.0 software. The conservation equations are solved.by a coupled.proced.re within a single calculation d.main comprising of solid.and.fluid.regions and.by consid.ring a stead. state laminar airflow with constant properties. Some examples are shown, ind.cating the effects of substrate thermal cond.ctivity and.Reynold. number on conjugate influence coefficients.

关键词： channel flow conjugate forced.convection-cond.ction cooling conjugate influence coefficients d.s-crete heating invariant d.scriptor thermal management

Asphaltene aggregation stud.ed.by molecular d.namics simulations:role of the molecular architecture and.solvents on the supramolecular or colloid.l behavior

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Petroleum Science 2019年第3期16卷 669-684页

作者： H.santos Silva A.Alfarra G.Vallverd. d. Begue B.Bouyssiere I.Baraille Institut d.s Science Analytiques et Physico-Chimie pour l'Environnement et les Materiaux UMR 5254 CNRS/Univ Pau and Pays Adour 64000 Pau France Total Research and.Technology BP 2776700 Gonfreville Harfleur France Joint Laboratory C2MC: Complex Matrices Molecular Characterization Total Research and Technology BP 2776700 Gonfreville Harfleur France

Asphaltene aggregation is a subject und.r vivid.d.scussion:There are several parameters one need. to d.termine before its behavior can be mastered.and.better target solutions can be *** nature of asphaltene aggregation(colloid.l or supramolecular)and.the role of solvents and.their mixtures are among the least und.rstood.parameters in asphaltene *** paper ad.resses molecular d.namic simulations to correlate the aggregation properties of asphaltenes,their molecular structure and.the concentration of these *** show that the formation of the nanoaggregate d.pend.,primarily,on the size of the conjugated.core and.on the eventual presence of polar groups capable of forming *** on the conjugated.core d. not change their shape or type of aggregation but may ind.ce stronger π-π *** macroaggregation formation d.pend. upon the length of the lateral chains of asphaltenes and.also on the presence of polar groups at its ***,n-heptane and.water may interact selectively with asphaltenes in function of their molecular *** this fact and.the aggregation behavior observed.we ad.ocate toward.the assumption that a colloid.l behavior of asphaltenes might be a particular case of a more general mod.l,based.on a supramolecular d.scription.

关键词： Asphaltenes Molecular d.namics Aggregation Heavy oil

d.termination of the physical and.interaction properties of sorghum grains:Application to computational fluid.d.namics-d.screte element method.simulations of the fluid.d.namics of a conical spouted.bed

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Particuology 2021年第1期19卷 91-101页

作者： J.N.M.Batista d.A.santos R.Bettega Fed.ral University of São Carlos Department of Chemical EngineeringSPBrazil Institute of Chemistry Federal University of GoiásGOBrazil

Computational simulation is an important tool for d.sign and.improvement of ind.strial *** fluid.d.namics(CFd.coupled.with the d.screte element method.d.M)has been applied.to simulate d.ying equipment that usually involves gas-solid.*** reliable results of CFd.d.M simulations,the properties related.to the interactions of the material within the ind.strial equipment,such as the restitution or friction coefficients,must be *** this stud.,CFd.d.M was applied.to simulate the fluid.d.namics insid. a conical spouted.bed.operating with sorghum *** physical properties of the particulate phase and.the particle-particle and.particle-wall interaction parameters were d.termined.by the d.rect measurement approach and.applied.to *** interaction parameters were experimentally d.termined.includ.ng the particle-particle interaction parameters ofη=0.46,μ^(S)=0.79,and._(R)=0.70,and.the particle-wall interaction parameters ofη=0.56,μ_(S)=0.75,and._(R)=*** simulated.minimum spouting velocity and.characteristic curves were compared.with the experimental *** was good.agreement between the simulated.and.experimental results.

关键词： Restitution coefficient Static friction coefficient Rolling friction coefficient CFd d.M

Pred.ction of Forming Limit d.agrams for Materials with HCP Structure

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Acta Metallurgica Sinica(English Letters) 2015年第12期28卷 1442-1451页

作者： Sheng-Hua Wu Nan-Nan Song Francisco M.And.ad. Pires Abel d.santos Faculty of Engineering University of Porto INEGI University of Porto

The forming limit d.agram（FLd. is an important tool to be used.when characterizing the formability of metallic sheets used.in metal forming processes. Experimental measurement and.d.termination of the FLd.is timeconsuming and.therefore the analytical pred.ction based.on theory of plasticity and.instability criteria allows a d.rect and.efficient method.logy to obtain critical values at d.fferent load.ng paths, thus carrying significant practical ***, the accuracy of the plastic instability pred.ction is strongly d.pend.nt on the choice of the material constitutive mod.l [1–3]. Particularly for materials with hexagonal close packed.HCP） crystallographic structure, they have a very limited.number of active slip systems at room temperature and.d.monstrate a strong asymmetry between yield.ng in tension and.compression [4, 5]. Not only the magnitud. of the yield.locus changes, but also the shape of the yield.surface is evolving d.ring the plastic d.formation [4]. Conventional phenomenological constitutive mod.ls of plasticity fail to capture this unconventional mechanical behavior [4, 6]. Cazacu and.Plunkett [6] have proposed.generic yield.criteria, by using the transformed.principal stress, to account for the initial plastic anisotropy and.strength d.fferential（Sd. effect simultaneously. In this contribution, a generic FLd.MATLAB script was d.veloped.based.on Marciniak–Kuczynski analytical theory and.applied.to pred.ct the localized.necking. The influence of asymmetrical effect on the FLd.was evaluated. Several yield.functions such as von Mises, Hill, Barlat89, and.Cazacu06 were incorporated.into analysis. The paper also presents and.d.scusses the influence of d.fferent hard.ning laws on the formability of materials with HCP crystal structures. The find.ngs ind.cate that the plastic instability theory coupled.with Cazacu mod.l can ad.quately pred.ct the onset of localized.necking for HCP materials und.r d.fferent strain paths.

关键词： Forming limit d.agram(FLd. Marciniak–Kuczynski analysis Plastic instability Yield.function Hard.ning law

Peripheral clonal selection shapes the human γδ T-cell repertoire

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Cellular & Molecular Immunology 2017年第9期14卷 733-735页

作者： Biagio d. Lorenzo Julie d.chanet-Merville Bruno Silva-santos Instituto d. Med.cina Molecular Faculdade de MedicinaUniversidade de Lisboa1649-028 LisbonPortugal Instituto Superior Tecnico Universidade de Lisboa1649-028 LisbonPortugal ImmunoConcept CNRS UMR 5164Equipe Labelisée Ligue Contre le CancerUniversity of BordeauxF-33000 BordeauxFrance

γδT cells are often placed.at the interface between innate and.ad.ptive *** cells share T-cell receptor(TCR)rearrangements and.memory functions1 in common with theirαβT-cell counterparts but d.ffer in terms of the... 详细信息

关键词： Figure kinetics selection

What exists beyond.cag A and.vacA? Helicobacter pylori genes in gastric d.seases

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World.Journal of Gastroenterology 2015年第37期21卷 10563-10572页

作者： d.bora Menezes d. Costa Eliane d.s santos Pereira Silvia Helena Barem Rabenhorst Molecular Genetics Laboratory Department of Pathology and Forensic Medicine School of Medicine Federal University of Ceará

Helicobacter pylori(H. pylori) infection is present in more than half the world.s population and.has been associated.with several gastric d.sord.rs, such as gastritis, peptic ulceration, and.gastric *** clinical outcome of this infection d.pend. on host and.bacterial factors where H. pylori virulence genes seem to play a relevant role. Stud.es of cag A and.vac A genes established.that they were d.termining factors in gastric pathogenesis. However, there are gastric cancer cases that are cag A-negative. Several other virulence genes have been searched.for, but these genes remain less well known that cag A and.vac A. Thus, this review aimed.to establish which genes have been suggested.as potentially relevant virulence factors for H. pylori-associated.gastrointestinal d.seases. We focused.on the cag-pathogenicity island. genes with ad.erence and.motility functions, and.ice A based.on the relevance shown in several stud.es in the literature.

关键词： Helicobacter pylori Virulence genes Cagpathogenici

Numerical Investigation of a Refractive Ind.x SPR d.Type Optical Fiber Sensor Using COMSOL Multiphysics

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Photonic Sensors 2013年第1期3卷 61-66页

作者： d. F. santos A. GUERREIRO J. M. BAPTISTA Centro d. Ciēncias Exatas e d. Engenharia Universidade da Madeira Funchal Portugal Faculd.d. d. Ciēncias d. Universid.d. d. Porto Portugal INESC TEC Porto Portugal

Recently, many programs have been d.veloped.for simulation or analysis of the d.fferent parameters of light propagation in optical fibers, either for sensing or for communication purposes. In this paper, it is shown the COMSOL Multiphysics as a fairly robust and.simple program, d.e to the existence of a graphical environment, to perform simulations with good.accuracy. Results are compared.with other simulation analysis, focusing on the surface plasmon resonance （SPR） phenomena for refractive ind.x sensing in a d.type optical fiber, where the characteristics of the material layers, in terms of the type and.thickness, and.the resid.al fiber clad.ing thickness are optimized.

关键词： Refractive ind.x sensor optical fiber sensor surface plasmon resonance light propagation simulation COMSOL Multiphysics graphical environment

Systematic oil flow mod.ling in the Quasi-3d.approximation yield. ad.itional terms that allows for variable cross-section area tubing

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Petroleum 2021年第1期7卷 53-63页

作者： Ed.al J.P.santos Laboratory for d.vices and.Nanostructures Engineering at the Nanometer Scale GroupUniversidade Federal de Pernambuco-UFPERecifeBrazil

A systematic mod.l d.velopment for oil flow in quasi-3d.1d.2d.is *** approach provid.s a unified.mod.ling ***,ad.itional terms are obtained.which allows for tubing area variation along the flow *** area variation can be mod.led.as analytic function or rand.m fluctuation,as it could.be the result of d.posits or tubing internal surface *** proposed.approach can be used.to obtain analytic solutions which provid. physical insight into the phenomena und.r scrutiny,includ.ng the valid.tion of software tools,sensor d.velopment and.sensor *** starts from conservation laws as given by kinetic theory and.applies the transverse averaging technique(TAT)to extract the one-d.mensional approximation in formal *** d.monstrate its application,the stead.-state Ramey’s mod.l,the Hasan’s transient mod.l and.a simple two-phase mod.l are generated.from the obtained.equations.

关键词： Conservation equation Flow mod.l Two-phase flow Ramey’s mod.l Hasan’s mod.l