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Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： r.A.JAFArI-TALOOKOLAEI h.GhANDVAr E.JUMAEV S.KhATIr T.CUONG-LE School of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and Science Center for Engineering Application and Technology Solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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Emerging analytical methods to characterize zeolite-based materials

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National Science review 2022年第9期9卷 47-66页

作者： Sophie h.van Vreeswijk bert M.Weckhuysen Inorganic Chemistry and Catalysis Debye Institute for NanomaterialsUtrecht University

Zeolites and zeolitic materials are,through their use in numerous conventional and sustainable applications,very important to our daily lives,including to foster the necessary transition to a more circular *** characterization of zeolite-based materials has a tremendous history and a great number of applications and properties of these materials have been discovered in the past *** review focuses on recently developed novel as well as more conventional techniques applied with the aim of better understanding zeolite-based *** explored analytical methods,*** probe tomography,scanning transmission X-ray microscopy,confocal fluorescence microscopy and photo-induced force microscopy,are discussed on their important contributions to the better understanding of zeolites as they mainly focus on the micro-to nanoscale chemical imaging and the revelation of structure-composition-performance *** other techniques have a long and established history,*** magnetic resonance,infrared,neutron scattering,electron microscopy and X-ray diffraction techniques,and have gone through increasing developments allowing the techniques to discover new and important features in zeolite-based *** to the increasing application of these methods,multiple techniques are nowadays used to study zeolites under working conditions(*** in situ/operando mode of analysis) providing new insights in reaction and deactivation mechanisms.

关键词： catalysis zeolites spectroscopy microscopy structure–composition–performance relationships

Machine Learning Techniques in Predicting hot Deformation Behavior of Metallic Materials

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 713-732页

作者： Petr Opela Josef Walek Jaromír Kopecek Department of Metallurgical Technologies Faculty of Materials Science and TechnologyVSB–Technical University of OstravaOstrava70800Czech Republic FZU—Institute of Physics of the Czech Academy of Sciences Prague18200Czech Republic

In engineering practice,it is often necessary to determine functional relationships between dependent and independent *** relationships can be highly nonlinear,and classical regression approaches cannot always provide sufficiently reliable ***,Machine Learning(ML)techniques,which offer advanced regression tools to address complicated engineering issues,have been developed and widely *** study investigates the selected ML techniques to evaluate their suitability for application in the hot deformation behavior of metallic *** ML-based regression methods of Artificial Neural Networks(ANNs),Support Vector Machine(SVM),Decision Tree regression(DTr),and Gaussian Process regression(GPr)are applied to mathematically describe hot flow stress curve datasets acquired experimentally for a medium-carbon *** the GPr method has not been used for such a regression task before,the results showed that its performance is the most favorable and practically unrivaled;neither the ANN method nor the other studied ML techniques provide such precise results of the solved regression analysis.

关键词： Machine learning Gaussian process regression artificial neural networks support vector machine hot deformation behavior

Metabolic and performance responses of male runners wearing 3 types of footwear: Nike Vaporfly 4%, Saucony Endorphin racing flats, and their own shoes

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Journal of Sport and health Science 2022年第3期11卷 275-284页

作者： Kim hébert-Losier Steven J.Finlayson Matthew W.Driller Blaise Dubois jean-François Esculier Christopher Martyn Beaven Division of health EngineeringComputing and ScienceTe Huataki Waiora School of HealthUniversity of WaikatoMount MaunganuiTauranga 3116New Zealand Sport and Exercise Science School of Allied HealthHuman Services and SportLa Trobe UniversityMelbourneVIC 3086Australia research&Development the Running ClinicLac-BeauportQC G3B 2J8Canada

Purpose We compared running economy(rE)and 3-km time-trial(TT)variables of runners wearing Nike Vaporfly 4%(VP4),Saucony Endorphin lightweight racing flats(FLAT),and their habitual running(OWN)*** Eighteen male recreational runners(age=33.5±11.9 year(mean±SD),peak oxygen uptake(VO_(2peak))=55.8±4.4 mL/kg·min)attended 4 sessions approximately 7 days *** first session consisted of a VO_(2peak) test to inform subsequent rE speeds set at 60%,70%,and 80%of the speed eliciting *** subsequent sessions,treadmill rE and 3-km TTs were assessed in the 3 footwear conditions in a randomized,counterbalanced crossover *** Oxygen consumption(mL/kg·min)was less in VP4(from 4.3%to 4.4%,p≤0.002)and FLAT(from 2.7%to 3.4%,p≤0.092)*** across intensities,with a non-significant difference between VP4 and FLAT(1.0%-1.7%,p≥0.292).Findings related to energy cost(W/kg)and energetics cost of transport(J/kg·m)were ***43-km TT performance(11:07.6±0:56.6 mm:ss)was enhanced *** by 16.6 s(2.4%,p=0.005)and *** by 13.0 s(1.8%,p=0.032).The 3-km times between OWN and FLAT(0.5%,p=0.747)were *** runners(n=11,61%)ran their fastest TT in *** Overall,VP4 improved laboratory-based rE measures in male recreational runners at relative speeds compared to OWN,but the rE improvements in VP4 were not significant *** runners exhibited better treadmill TT performances in VP4(61%)***(22%)and OWN(17%).The variability in rE(-10.3%to 13.3%)and TT(-4.7%to 9.3%)improvements suggests that responses to different types of shoes are individualized and warrant further investigation.

关键词： Footwear Individual responses Minimalist Physiology running

Dynamic stress concentration in an infinitely long cylindrical cavity due to a point spherical source embedded within a fluid-saturated poroelastic formation of infinite extent

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 139-156页

作者： h.hOSSEINI O.BALILAShAKI Department of Mechanical Engineering Faculty of EngineeringGolestan University

The effects of a harmonically exciting monopole source on an infinitely long cylindrical cavity embedded entirely within a fluid-saturated poroelastic formation of infinite extent are examined theoretically. It is assumed that the source is located outside the cavity at a specified distance from the borehole axis. The magnitudes of the hoop and radial stresses beside the pore pressures exerted on the interface and inside the porous medium surrounding the borehole are calculated and discussed. Biot's poroelastic modeling along with three types of boundary conditions for the cylindrical interface including the ideal fluid, empty borehole, and rigid inclusion with a hard boundary is employed for the analysis. Utilizing a proper translational addition theorem for expressing the incident spherical wave in terms of cylindrical wave expansions, the proposed boundary conditions at the interface are satisfied. Stresses are formulated by means of wave potential functions in a three-dimensional(3D) manner. The effects of the frequency and the radial distance between the source and borehole on the induced stresses are examined for the first cylindrical modes over frequency spectra. Two permeability conditions for the interface and three types of soils for the porous formation are considered throughout the analysis. To give an overall outline of the study, a numerical example is presented. The results clearly indicate that the distance is a key parameter and has considerable effects on the induced stress values. In addition, the interface permeability condition and soil characteristics play an important role in determining the dynamic response of the borehole. Finally,the obtained results are compared with the relevant analyses existing in the literature for some limit cases, and good agreement is achieved.

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XPZLIB:an hDF5-format multi-group cross-section library

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Nuclear Science and Techniques 2024年第11期35卷 46-60页

作者： Bin Fu Le-rui Zhang Ding She Chun-Lin Wei Alain hébert Institute of Nuclear and New Energy Technology Key Laboratory of Advanced Reactor Engineering and Safety of the Ministry of EducationTsinghua UniversityBeijing 100084China National Key Laboratory of Nuclear reactor Technology Nuclear Power Institute of ChinaChengdu 610041China Polytechnique Montreal MontrealCanada

A multi-group cross-section library is fundamental for deterministic lattice physics *** existing multi-group cross-section libraries are customized for particular computer codes,as well as for particular types of nuclear *** paper presents an hDF5-format multi-group cross-section library named *** was produced using a selfdeveloped XPZr module integrated into the NJOY2016 code,and an in-house PyNjoy2022 system was developed for *** contains detailed data content and well-organized data structures that are user-and *** typical XPZLIBs with different numbers of energy groups,nuclides,and depletion reaction types were released via the Tsinghua cloud ***,the applicability of the released XPZLIBs was investigated using hTGr and PWr lattice calculations,which can provide guidance for applying XPZLIB under different scenarios.

关键词： XPZLIB Multi-group library hDF5 format hTGr PWr

Neuroinflammation as a therapeutic target in huntington's disease

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Neural regeneration research 2025年第3期20卷 817-818页

作者： Andrea Kwakowsky Thulani h.Palpagama Center for Brain research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CentreUniversity of GalwayGalwayIreland

In 1872, George huntington presented his essay “On Chorea” to the Meigs and Mason Academy of Medicine and, in doing so, detailed a disease that would later bear his name. huntington's disease(hD) is a genetic, neurodegenerative disease that manifests as the loss of motor control,cognitive impairment,and mood and psychiatric changes in paents.

关键词： huntington inflammation Medicine

Glial response in the midcingulate cortex in huntington’s disease

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Neural regeneration research 2025年第1期20卷 207-208页

作者： Thulani h.Palpagama Andrea Kwakowsky Center for Brain research and Department of Anatomy and Medical Imaging Faculty of Medical and Health SciencesUniversity of AucklandAucklandNew Zealand Pharmacology and Therapeutics School of MedicineGalway Neuroscience CenterUniversity of GalwayGalwayIreland

huntington’s disease(hD)is a genetic disease characterized by the progressive degeneration of the striatum and *** can present with a variety of symptoms that can broadly be classified into motor symptoms,inclusive of choreatic movements and rigidity,mood and psychiatric symptoms,such as depression and apathy,and cognitive symptoms,such as cognitive *** causal mutation underlying hD results from an expansion of a CAG repeat sequence on the IT15 gene,resulting in the formation and accumulation of a mutant huntingtin protein.

关键词： huntington degeneration cortex

A new modeling approach of pressure waves at the inlet of internal combustion engines

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Journal of Thermal Science 2011年第2期20卷 181-188页

作者： David Chalet Alexandre Mahé jean-Franois hétet Jérme Migaud Internal Combustion Engine Team Laboratory of Fluid Mechanics UMR CNRS 6598 Ecole Centrale de Nantes Advanced development Mann+Hummel France

This paper presents a new model used to describe the propagation of pressure waves at the inlet systems of internal combustion engine. In the first part, an analogy is made between the compressible air in a pipe and a mechanical ideal mass damper spring system. A new model is then presented and the parameters of this model are determined by the use of an experimental setup (shock tube test bench). With this model, a transfer function is defined in order to link directly the pressure and the air mass flow rate. In the second part, the model is included into an internal combustion engine simulation code. The results obtained with this code are compared to experimental ones which are measured on a one-cylinder engine test bench. This last one is driven by an electric motor in order to study only the effect of the pressure waves on the engine behavior. A good agreement is obtained between the experimental results and the numerical ones and the new approach is an alternative method for modeling the pressure wave phenomena in an internal combustion engine manifold.

关键词： gas dynamics pressure wave compressible flow frequency analysis transfer function internal combustion engine