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Modelling dynamic pantograph loads with combined numerical analysis

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Railway Engineering Science 2024年第1期32卷 81-94页

作者： F.F.Jackson R.Mishra J.M.Rebelo J.Santos P.Antunes J.Pombo H.Magalhaes L.Wills M.Askill School of Computing and Engineering University of HuddersfieldHuddersfieldUK School of Computing and Engineering Institute of Railway ResearchUniversity of HuddersfieldHuddersfieldUK IDMEC Instituto Superior TecnicoUniversidade de LisboaLisbonPortugal ISEL Instituto Politecnico de LisboaLisbonPortugal Hitachi Rail Newton AycliffeUK Wabtec/Brecknell Willis ChardUK

Appropriate interaction between pantograph and catenary is imperative for smooth operation of electric trains.Changing heights of overhead lines to accommodate level crossings,overbridges,and tunnels pose significant challenges in maintaining consistent current collection performance as the pantograph aerodynamic profile,and thus aerodynamic load changes significantly with operational height.This research aims to analyse the global flow characteristics and aerodynamic forces acting on individual components of an HSX pantograph operating in different configurations and orientations,such that the results can be combined with multibody simulations to obtain accurate dynamic insight into contact forces.Specifically,computational fluid dynamics simulations are used to investigate the pantograph component loads in a representative setting,such as that of the recessed cavity on a Class 800 train.From an aerodynamic perspective,this study indicates that the total drag force acting on non-fixed components of the pantograph is larger for the knuckle-leading orientation rather than the knuckle-trailing,although the difference between the two is found to reduce with increasing pantograph extension.Combining the aerodynamic loads acting on individual components with multibody tools allows for realistic dynamic insight into the pantograph behaviour.The results obtained show how considering aerodynamic forces enhance the realism of the models,leading to behaviour of the pantograph-catenary contact forces closely matching that seen in experimental tests.

关键词： Pantograph-catenary interaction Pantograph aerodynamics Computational fluid dynamics Pantograph loads Current collection performance

ntegrated approach to winery waste： waste generation and data consolidation

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Frontiers of Environmental Science & Engineering 2016年第1期10卷 168-176页

作者： Margarida OLIVEIRA Elizabeth DUARTE instituto Superior de Agronomia (ISA) University of Lisbon 1349-017 Lisboa Portugal Escola Superior Agrairia de santarem (ESAS) Instituto Superior Politecnico de Santarem 2001-904 Santarem Portugal

The winemaking process involves the genera- tion of a significant amount of waste and wastewater. These residues should be addressed for recycling or treatment before being returned to environment. As each winery is unique in waste generation and disposal, plans for environmentally friendly waste management are not universal and should be tested for their effectiveness. In this study, a diagnostic was made during three years, in different wineries, throughout Portugal, in order to quantify and characterize the waste and the wastewater produced. The results showed that solid waste and wastewater are mainly produced during the harvest period, corresponding to 74% and 87%, respectively. One ton of processed grape approximately produce 0.13 t marc, 0.06 t lees, 0.03 t of stalks and 1.65 m3 of wastewater. No significant differences （P≤0.05） were observed for grape marc, lees and wastewater ratios, between years or wineries. With respect to the stalk ratio, there was no effect of year but the winery significantly affected this ratio （P ≤ 0.05）. During the study period the treated wastewater, since diluted, revealed suitable characteristics for irrigation representing an additional source of water. In this regard, the data acquisition and consolidation ensure the transfer of information and experience which constitute an essential step in a support decision tool design.

关键词： waste management wastewater reuse winerywastewater

Asthma, bronchiectasis, and chronic obstructive pulmonary disease: the Bermuda Triangle of the airways

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Chinese Medical Journal 2022年第12期135卷 1390-1393页

作者： Miguel Angel Martinez Garcia Joan B.Soriano Pneumology department Hospital Universitario y Politecnico la Fe de ValenciaSpain CIBERES de enfermedades respiratorias Instituto de salud Carlos IIIMadridSpain Servicio de Neumologia Hospital Universitario de la PrincesaMadridSpain Facultad de Medicina Universidad Autonoma de MadridMadridSpain

Also known as the devil's Triangle or Hurricane Alley,the Bermuda Triangle is an area of the Atlantic Ocean with vertices in Miami,San Juan de Puerto Rico,and Bermuda,which has been credited for causing mass disappear... 详细信息

关键词： airway obstructive Atlantic

The neuroprotective effect of traditional Chinese medicinal plants--A critical review

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Acta Pharmaceutica Sinica B 2023年第8期13卷 3208-3237页

作者： Joao Moreira Mariana Machado Monica Dias-Teixeira Ricardo Ferraz Cristina delerue-Matos Clara Grosso REQUIMTE/LAQV Instituto Superior de Engenharia do PortoInstituto Politecnico do PortoPorto 4249-015Portugal Ciencias Químicas e das Biomoleculas/CISA Escola Superior de SaudedInstituto Politecnico do PortoPorto 4200-072Portugal NICiTeS-Nucleo de Investigacao em Ciencias e Tecnologias da Saude Escola Superior de Saude Ribeiro SanchesLisboa 1950-396Portugal REQUIMTE/LAQV Departamento de Química e Bioquímica Faculdade de CienciasUniversidade do PortoPorto 4169-007Portugal

Neurodegenerative and neuropsychiatric diseases are increasingly affecting individuals’quality of life,thus increasing their cost to social and health systems.These diseases have overlapping mechanisms,such as oxidative stress,protein aggregation,neuroinflammation,neurotransmission impairment,mitochondrial dysfunction,and excitotoxicity.Currently,there is no cure for neurodegenerative diseases,and the available therapies have adverse effects and low efficacy.For neuropsychiatric disorders,such as depression,the current therapies are not adequate to one-third of the patients,the so-called treatmentresistant patients.So,searching for new treatments is fundamental.Medicinal plants appear as a strong alternative and complement towards new treatment protocols,as they have been used for health purposes for thousands of years.Thus,the main goal of this review is to revisit the neuroprotective potential of some of the most predominant medicinal plants(and one fungus)used in traditional Chinese medicine(TCM),focusing on their proven mechanisms of action and their chemical compositions,to give clues on how they can be useful against neurodegeneration progression.

关键词： Neurodegeneration Alzheimer's disease Parkinson's disease depression Medicinal plants Oxidative stress Toxicology Clinicaltrials

Explicit Relations of Physical Potentials Through Generalized Hypervirial and Kramers' Recurrence Relations

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Communications in Theoretical Physics 2015年第6期63卷 682-686页

作者：孙国华董世海 Catedra CONACyT Centro de Investigacion en ComputacionInstituto Politecnico Nacional departamento de Fisica Escuela Superior de Ffsica y MatematicasInstituto Politecnico Nacional

Based on a Hamiltonian identity,we study one-dimensional generalized hypervirial theorem,Blanchardlike(non-diagonal case) and Kramers'(diagonal case) recurrence relations for arbitrary x~κ which is independent of the central potential V(x).Some significant results in diagonal case are obtained for special κ in x~κ(κ≥ 2).In particular,we find the orthogonal relation(n_1|n_2) = δ_(n_1n_2)(κ = 0),(n_1|V'(x)\n_2) =(E_(n_1)-E_(n_2))~2〈n_1x|n_2)(κ = 1),E_n =(n/V'(x)x/2|n) +(n|V(x)|n)(κ = 2) and-4E_n(n|x|n) +(n|V'(x)x^2\n〉 +4〈n|V(x)x|n〉 = 0(κ = 3).The latter two formulas can be used directly to calculate the energy levels.We present useful explicit relations for some well known physical potentials without requiring the energy spectra of quantum system.

关键词：广义力显式物理复发递推关系正交关系能量水平量子系统

Optimal distribution of active piezoelectric elements for noise attenuation in sandwich panels

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International Journal of Smart and Nano Materials 2020年第4期11卷 400-416页

作者： J.F.A.Madeira A.L.Araujo IDMEC Instituto Superior TecnicoUniversidade de LisboaLisboaPortugal ADM ISELInstituto Politecnico de LisboaLisboaPortugal

In this paper,a multiobjective optimization approach for obtaining the optimal distribution of surface-bonded piezoelectric sensors and actua-tors for noise attenuation in sandwich panels is presented.The noise attenuation is achieved by using negative velocity feedback control with co-located sensors and actuators.The control gains are also optimized in order to obtain the most efficient noise attenuation in a given frequency band.An in-house implementation of a viscoelastic soft core sandwich plate finite element,including surface-bonded piezoelectric sensors and actuators with active control capabilities,is used for obtaining the frequency response of the panels.The sound transmission capability of the panels is evaluated using the radiated sound power,along with the Rayleigh integral approach,which is suitable for lightly coupled structural/acoustic problems.The Direct MultiSearch(DMS)optimization algorithm is used to minimize the added weight due to the piezoelectric material,minimizing also the number of required controllers and maximizing the noise attenuation.The total length of the radiated sound power curve is shown to be an effective measure of noise attenuation in a given frequency band.Trade-off Pareto fronts and the obtained optimal configurations are presented and discussed.

关键词： Sandwich structures piezoelectricity viscoelasticity active damping multiobjective optimization

design and Implementation of a Rehabilitation Upper-limb Exoskeleton Robot Controlled by Cognitive and Physical Interfaces

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Journal of Bionic Engineering 2022年第5期19卷 1374-1391页

作者： Arturo Gonzalez‑Mendoza Ivett Quinones‑Uriostegui Sergio Salazar‑Cruz Alberto‑Isaac Perez‑Sanpablo Ricardo Lopez‑Gutierrez Rogelio Lozano LAFMIA UMI Center for Research and AdvancedStudies of National Polytechnic InstituteAv.Instituto Politecnico Nacional No.250807360 Mexico CityMexico Motion Analysis Lab National Institute of Rehabilitation Luis Guillermo Ibarra IbarraCalz.Mexico Xochimilco No.28914389 Mexico CityMexico CONACYT-CINVESTAV Av.Instituto Politecnico Nacional 250807360 Mexico CityMexico UTC-CNRS UMR Sorbonne UniversitesUTC-CNRS UMR7253 HeudiasycCompiegneFrance

This paper presents an upper limb exoskeleton that allows cognitive(through electromyography signals)and physical user interaction(through load cells sensors)for passive and active exercises that can activate neuroplasticity in the rehabilitation process of people who suffer from a neurological injury.For the exoskeleton to be easily accepted by patients who suffer from a neurological injury,we used the ISO9241-210:2010 as a methodology design process.As the first steps of the design process,design requirements were collected from previous usability tests and literature.Then,as a second step,a technological solution is proposed,and as a third step,the system was evaluated through performance and user testing.As part of the technological solution and to allow patient participation during the rehabilitation process,we have proposed a hybrid admittance control whose input is load cell or electromyography signals.The hybrid admittance control is intended for active therapy exercises,is easily implemented,and does not need musculoskeletal modeling to work.Furthermore,electromyography signals classification models and features were evaluated to identify the best settings for the cognitive human–robot interaction.

关键词： Human Robot interaction Hybrid admittance control Surface electromyography Upper-limb exoskeletal robot

Tetrapartite entanglem ent features of W-C lass state in uniform acceleration

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Frontiers of physics 2020年第1期15卷 1-8页

作者： Qian Dong Ariadna J.Torres-Arenas Guo-Hua Sun Shi-Hai Dong Laboratorio de Informacion Cuantica CIDETECInstituto Politecnico NacionalUPALMCDMX 07700Mexico Catedratica CONACyT Centro de Investigacion en ComputacionInstituto Politecnico NacionalUPALMCDMX 07738Mexico

Using the single-mode approximatiou,we first calculate entanglement measures such as negativity(1-3 and 11 tangles)and von Neumann entropy for a tetrapartite W-Class system in noninertial fiarne and then anal^e the whole entanglement measures,the residualπ4 and geometricП4 average of tangles.Notice that the difference betweenπ4 andП4 is very small or disappears with the increasing accelerated observers.The entanglement properties are compared among the different cases from oue accelerated observer to four accelerated observers.The results show that there still exists entanglement for the complete system even when accelemtion r tends to infinity.The degree of entanglement is disappeared for the 1-1 tangle case when the acceleration r>0.472473.We reexamine the Unriih effect in noninertiai frames.It is shown that the entanglement system in which only one qubit is accelerated is more robust than those eutangled systems in whicli two or three or four qubits are accelerated.It is also found that the von Neumann entropy S of the total system always increases with the increasing accelerated observers,but the Sκξand Sκζδwith two and three involved noniuertial qubits first increases and then decreases with the acceleration parameter r,but they are equal to constants 1 and 0.811278 respectively for zero involved iioniiiertial qubit.

关键词： tetrapartite W-Class state entanglement Dirac field noninertiai frames

Foaming supramolecular surfactants for gas mobility control in naturally fractured carbonate reservoirs at high temperature,salinity,and hardness

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Petroleum Science 2022年第6期19卷 3134-3148页

作者： Enrique Soto-Castruita Raúl Hern andez-Altamirano Eduardo Buenrostro-González Erick-Emanuel Luna-Rojero Sung Jae Ko-Kim Violeta-Yasmín Mena-Cervantes Mirna Pons-Jiménez Jorge-Francisco Ramírez-Pérez David-Aaσn Nieto-Alvarez Ricardo Cerón-Camacho Jos e-Ernesto Parra Raúl Oviedo-Roa Jos e-Manuel Martínez-Magadán Rodolfo Cisneros-Dévora Luis-S.Zamudio-Rivera instituto Mexicano del Petr oleo Eje Central Lazaro Cardenas Norte 152Col.San Bartolo AtepehuacanCiudad de Mexico07730Mexico CONACy T-instituto Mexicano del Petroleo Eje Central Lazaro Cardenas Norte 152Col.San Bartolo AtepehuacanCiudad de Mexico07730Mexico Centro Mexicano para la Produccion mas Limpia Instituto Politecnico NacionalAvenida Acueducto s/nCol.La Laguna TicomanCiudad de Mexico07340Mexico Centro de Tecnologías para Exploracion y Produccion Camino de Terracería 800Col.San Jose NovilleroBoca delRíoVeracruz94286Mexico

Oil production and mainte nance are essential issues in naturally fractured reservoirs because they are the largest and most productive on earth.However,they present early water and gas channeling but could be remediated by using foaming agents to control these phenomena through blocking channeling areas.In Mexico these reservoirs have pressure up to 5,500 psi,high temperature up to 200℃,salinity up to400,000 ppm,and hardness up to 250,000 ppm;due to these thermodynamic conditions,there has been no available technology to form stable enough foams.In this work,a foaming supramolecular surfactant with the capability to chelate Ca^(2+)ions is examined.As a result,surfactant monomers are bridged by captured Ca^(2+)cations leading to the formation of high-molecular-weight oligomers,which significantly increment the viscosity of the solution improving the foam stability,and since at this manner the Ca2+cations are no longer available to precipitate as components of solid salts,the foaming supramolecular surfactant also performs as antiscalant.These observations are explained through quantum theoretical modeling.The foam is stable,effectively blocking the gas channels,whereas in presence of oil the foam is broken leading the oil to pass into the wellbore.The characteristic rheological properties of the foam allow its injection into the formation at a range of flow rates,foam qualities,and shear stress to achieve the flooding and the blocking of a variety of fractured carbonate formations,and the change of the wettability of the matrix,which is a desirable behavior in a huff and puff process,as reported in a previous publication about a successful pilot test of this foam.

关键词： Calcium chelation Foaming composition Supramolecular surfactant Molecular design Gas mobility control Flow assurance Improved oil recovery Conformance control