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Influence of railway wheel tread damage on wheel-rail impact loads and the durability of wheelsets

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Railway Engineering science 2024年第1期32卷 20-35页

作者： Michele Maglio Tore Vernersson Jens C.o.Nielsen Anders Ekberg Elena Kabo CHARMEC Department of Mechanical and Maritime SciencesChalmers University of TechnologySE‑41296 GothenburgSweden

Dynamic wheel-rail contact forces induced by a severe form of wheel tread damage have been measured by a wheel impact load detector during full-scale field tests at different vehicle *** on laser scanning,the measured three-dimensional damage geometry is employed in simulations of dynamic vehicle-track interaction to calibrate and verify a simulation *** relation between the magnitude of the impact load and various operational parameters,such as vehicle speed,lateral position of wheel-rail contact,track stiffness and position of impact within a sleeper bay,is *** calibrated model is later employed in simulations featuring other forms of tread damage;their effects on impact load and subsequent fatigue impact on bearings,wheel webs and subsurface initiated rolling contact fatigue of the wheel tread are *** results quantify the effects of wheel tread defects and are valuable in a shift towards condition-based maintenance of running gear,and for general assessment of the severity of different types of railway wheel tread damage.

关键词： Wheel tread damage Rolling contact fatigue cluster Field measurements Dynamic vehicle-track interaction Wheel-rail impact load Wheelset durability

Are dogs not susceptible to retroviral infections?

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动物疾病（英文） 2024年第3期4卷 217-223页

作者： Jorge Casseb João Henrique Campos Luciano Rodrigo Lopes Laboratory of Investigation in Dermatology and Immunodeficiencies Department of DermatologyUniversity of São Paulo Medical SchoolSão PauloSPBrazil Igen-Institute of Immunogenetics São PauloSPBrazil Bioinformatics and Biomedical Data science Division Health Informatics DepartmentUniversidade Federal de São Paulo-UNIFESP.Rua Botucatu 862Prédio Leal Pradotérreo Vila Clementino CEP 04023-062 São PauloSPBrazil

Retroviruses have been proven to cause infections and diseases in a series of mammalian hosts but not in ***,this letter discussed the dog susceptibility to retrovirus infection,encompassing arguments to understand why dogs may have not been infected by retroviruses thus *** potential resistance of retrovirus in dogs enables this provocative short communication to discuss this question,looking at some evolutive *** lineage of canids has shown,throughout its evolutionary history,a smaller accumulation of retroviruses in canid genomes,classified as endogenous *** this context,the genomes of canids seem to offer obstacles,which have been evolu-tionarily conserved,in the face of retroviral infection.

关键词： Retrovirus dogs Endogenous retrovirus

Tensor force impact on shell evolution in neutron-rich si and Ni isotopes

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Chinese Physics C 2024年第4期48卷 95-106页

作者： s.V.sidorov A.s.Kornilova T.Yu.Tretyakova Faculty of Physics Lomonosov Moscow State UniversityMoscow 119991Russia skobeltsyn Institute of Nuclear Physics Lomonosov Moscow State UniversityMoscow 119991Russia

The influence of the tensor interaction of nucleons on the characteristics of neutron-rich silicon and nickel isotopes was studied in this *** forces are considered within the framework of the Hartree-Fock approach with the skyrme *** addition of a tensor component of interaction is shown to improve the description of the splittings between different single-particle states and decrease nucleon-nucleon pairing correlations in silicon and nickel *** attention was directed toward the role of isovector tensor forces relevant to the interaction of like nucleons.

关键词： nuclear shell model tensor interaction silicon isotopes nickel isotopes

A Review on the Recent Trends of Image steganography for VANET Applications

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Computers, Materials & Continua 2024年第3期78卷 2865-2892页

作者： Arshiya s.Ansari Department of Information Technology College of Computer and Information SciencesMajmaah UniversityAl-Majmaah11952Saudi Arabia

Image steganography is a technique of concealing confidential information within an image without dramatically changing its outside *** vehicular ad hoc networks(VANETs),which enable vehicles to communicate with one another and with roadside infrastructure to enhance safety and traffic flow provide a range of value-added services,as they are an essential component of modern smart transportation *** steganography has been suggested by many authors for secure,reliable message transfer between terminal/hope to terminal/hope and also to secure it from attack for privacy *** paper aims to determine whether using steganography is possible to improve data security and secrecy in VANET applications and to analyze effective steganography techniques for incorporating data into images while minimizing visual quality *** to simulations in literature and real-world studies,Image steganography proved to be an effectivemethod for secure communication on VANETs,even in difficult network *** this research,we also explore a variety of steganography approaches for vehicular ad-hoc network transportation systems like vector embedding,statistics,spatial domain(sD),transform domain(TD),distortion,masking,and *** study possibly shall help researchers to improve vehicle networks’ability to communicate securely and lay the door for innovative steganography methods.

关键词： steganography image steganography image steganography techniques information exchange data embedding and extracting vehicular ad hoc network(VANET) transportation system

The emerging role of exercise as a cancer treatment

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Journal of sport and Health science 2024年第4期13卷 443-444页

作者： Kerry s.Courneya Faculty of Kinesiology Sportand RecreationCollege of Health SciencesUniversity of AlbertaEdmontonAlbertaT6G 2H9Canada

over the past few decades,exercise oncology has emerged as an important subfield within exercise *** that time,substantial progress has been made in understanding the role of exercise in people newly diagnosed with ca... 详细信息

关键词： cancer treatment exercise

4He monolayer on graphene: a quantum Monte Carlo study

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Communications in Theoretical Physics 2024年第9期76卷 151-159页

作者： s Yu M Boninsegni Department of Physics University of Alberta

We revisit the problem of adsorption of a single4He layer on graphene, focusing on the commensurate(C1/3) crystalline phase, specifically on whether it may possess a nonzero superfluid response, and on the existence of superfluid phases, either（metastable） liquid or vacancy-doped crystalline. We make use of canonical quantum Monte Carlo simulations at zero and finite temperature, based on a realistic microscopic model of the system. our results confirm the absence of any superfluid response in the commensurate crystal, and that no thermodynamically stable uniform phase exists at lower coverage. No evidence of a possibly long-lived, metastable superfluid phase at C1/3coverage is found. Altogether, the results of ground-state projection methods and finite-temperature simulations are entirely consistent.

关键词： helium low-dimensional systems quantum Monte Carlo superfluidity supersolids

FEA-based Geometrical Modification of switched Reluctance Motor for Radial Force Reduction

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Chinese Journal of Electrical Engineering 2024年第1期10卷 124-135页

作者： Rani s Jayapragash R school of Electrical Engineering Vellore Institute of TechnologyChennai 600127India

switched reluctance motors(sRMs)are becoming increasingly popular in the automotive sector owing to their robust ***,sRMs are preferred particularly for EV applications owing to their fault tolerance,magnet-free structure,and high power/torque *** main concerns of sRM compared to other machines include torque ripple and *** primary cause of vibration is the radial force created by the sRM.A geometry-based modification of the sRM to reduce the radial force without significantly changing the average torque produced is *** primary goal is to design a 4-phase,8/6 sRM with a lower radial *** possible geometrical alterations are proposed:one with square windows and the other with circular holes on the rotor *** windows are sized and positioned to avoid flux *** criteria are developed for the optimal window size and *** element analysis(FEA)modelling of the sRM is used to validate its *** FEA results are compared with the performance parameters obtained using the analytical *** the multiphysics design tool ANsYs to obtain the natural frequencies and associated deformations through modal *** to the conventional geometry,the radial force is significantly reduced by providing windows.

关键词： 8/6 sRM radial force modal analysis FEA analysis natural frequencies sRM with windows

Chiral forces in longitudinally invariant dielectric photonic waveguides

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Photonics Research 2024年第3期12卷 431-443页

作者： JosEP MARTÍNEZ-RoMEU IAGo DIEZ sEBAsTIAN GoLAT FRANCIsCo J.RoDRÍGUEZ-FoRTUÑo ALEJANDRo MARTÍNEZ Nanophotonics Technology Center Universitat Politècnica de ValènciaValencia 46022Spain Department of Physics King’s College LondonLondon WC2R 2LSUK

We calculate numerically the optical chiral forces in rectangular cross-section dielectric waveguides for potential enantiomer *** study considers force strength and time needed for separating chiral nanoparticles,mainly via quasi-TE guided modes at short wavelengths(405 nm)and the 90°-phase-shifted combination of quasi-TE and quasi-TM modes at longer wavelengths(1310 nm).Particle tracking simulations show successful enantiomer separation within two *** results suggest the feasibility of enantiomeric separation of nanoparticles displaying sufficient chirality using simple silicon photonic integrated circuits,with wavelength selection based on the nanoparticle size.

关键词： dielectric forces quasi

A decomposition of light’s spin angular momentum density

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Light(science & Applications) 2024年第8期13卷 1578-1589页

作者： Alex J.Vernon sebastian Golat Claire Rigouzzo Eugene A.Lim Francisco J.Rodríguez-Fortuño Department of Physics King’s College LondonStrandLondon WC2R 2LSUK London Centre for Nanotechnology LondonUK

Light carries intrinsic spin angular momentum(sAM)when the electric or magnetic field vector rotates over time.A familiar vector equation calculates the direction of light’s sAM density using the right-hand rule with reference to the electric and magnetic polarisation *** Maxwell’s equations,this vector equation can be decomposed into a sum of two distinct terms,akin to the well-known Poynting vector decomposition into orbital and spin *** present the first general study of this spin decomposition,showing that the two terms,which we call canonical and Poynting spin,are chiral analogies to the canonical and spin momenta of light in its interaction with *** canonical momentum,canonical spin is directly *** canonical and Poynting spin incorporate spatial variation of the electric and magnetic fields and are influenced by optical *** decomposition allows us to show that a linearly polarised vortex beam,which has no total sAM,can nevertheless exert longitudinal chiral pressure due to equal and opposite canonical and Poynting spins.

关键词： canonical momentum angular