bluuebunny/crossref_metadata_2025_split huggingface dataset:
An adaptive reduction method for viscoelastic structures without approximation on viscoelasticity
Authors: Zhang Shuyang , Belle Lucas Van , Devriendt Hendrik , Desmet Wim 
Published: December 2024

Abstract
Viscoelastic materials are often encountered in engineering applications, such as bonded assemblies, polymer structures, or structures with damping treatments. To simulate the dynamic behavior of large mechanical systems with viscoelastic materials, finite element (FE) models are commonly employed. However, the large size of these models can lead to significant computational costs, making model order reduction (MOR) often a necessary step for improving the computational efficiency. Recently, an adaptive Taylor-based second-order Arnoldi (AT-SOAR) algorithm was introduced, which addresses the frequency-dependency of viscoelastic materials. However, due to the Taylor-based approximation used in the viscoelastic behavior modelling, the resulting reduced order models (ROMs) may leave room for improvement, both from an accuracy as well as from an efficiency point of view. Hence, this work proposes a two-layer Krylov subspace (TLK) method that circumvents the viscoelastic model approximation. Additionally, a sequenced collection approach is used to augment the reduction basis from these two layers of Krylov subspaces. For automating ROM generation in line with specific error criteria, the TLK method is integrated with the adaptive algorithm in AT-SOAR (A-TLK). The proposed method is demonstrated through an adhesive single-lap model example, showing that A-TLK can generate smaller, more efficient ROMs compared to AT-SOAR under the same error tolerance.
The contribution of higher order modes to shock response spectra
Authors: Dubber Kyle , Ferguson Neil , Waters Timothy 
Published: December 2024

Abstract
The shock response spectrum is a widely used design tool that engineers use when assessing the severity of transient excitation on a structure. The shock response spectrum is typically defined as the peak response of a series of single degree-of-freedom (DOF) oscillators each with a different natural frequency. For structures representable by a single DOF system, such is the case when only a single mode dominates the response, the shock response spectrum can be used to evaluate this response directly and a brief review of the existing accepted metrics is presented. In general, the response of many structures may comprise contributions from higher order modes leading to inadequate predictions from the shock response spectrum, especially for acceleration responses. In such cases a form of shock response spectrum can be obtained that accounts for all modes of vibration but as a function of shock duration. However, a multi-modal model of the structure is then required and its shock response obtained numerically over a range of shock durations which can be computationally expensive and less amenable to physical interpretation.
This paper adopts a previously proposed modal approach to obtaining the shock response of systems with contributions from higher order modes, in which the transient response is calculated for each mode in turn which are then superposed. A key question that arises is the number of modes that need to be retained in the summation. Two numerical case studies are presented which explore modal convergence for displacement, velocity and acceleration shock response spectra. Results suggest that a priori mode selection is not generally possible although inspection of the mode shapes can offer guidance. However, the benefit of the modal approach to interpretability of the results is illustrated.
Vibration-Based Crack Detection in Plates Using Natural Frequency Degradation.
Authors: Satpute A A , Kennedy D , Featherston C A , Kundu A 
Published: December 2024

Abstract
Structural cracks reduce the performance and service life of buildings, bridges, and aircraft structures, leading to catastrophic failures resulting in economic losses and fatalities. To avoid such consequences, regular health monitoring and maintenance is required, especially for critical structures that carry high levels of dynamic and fatigue loading and whose failure would be catastrophic. Many techniques are available for structural health monitoring, including visual inspection, ultrasonic testing, acoustic emission, magnetic field, and vibrational-based methods. Any damage causes degradation in the natural frequencies and vibration modes of a structure, which are considered in vibration-based methods to characterize the damage. The focus of this research is to develop a more efficient method for the detection and characterisation of arbitrarily oriented surface cracks in isotropic plates, in terms of five parameters, namely the longitudinal and transverse location, length, depth and orientation. To achieve this objective, an analytical solution based on strain energy is used to generate synthetic data that quantifies changes in the natural frequencies for different crack locations and intensities based on noise-free simulation. The inverse problem, i.e. the determination of the crack parameters based on measured changes in natural frequencies can then be solved based on the use of synthetic data with a gradient based optimisation technique.
Modelling and Simulating the Primary Vertical Hydraulic Railway Dampers DISPEN
Authors: Mwakitabu Simon , Ichchou Mohamed , Bareille Olivier , Nechak Lyes , Trabelsi Amin , Valette Lionel 
Published: December 2024

Abstract
The train’s bogie consists of suspension systems and mechanical links. The hydraulic damper is a crucial part of the suspension system to ensure safety and comfort. The primary vertical damper mostly linear is responsible for reducing vibrations transmitted from the rails to the wheels of a High Speed Train. During the damper design, certain geometric parameters such as the diameter of the valves, spring constant, preload force and valve orifice diameter are adjusted to achieve the desired force-velocity characteristic by DISPEN. This process can be both cumbersome and costly in terms of time and money. A non-linear physical model is developed solving stiff ordinary differential equations predicting the dynamic pressure variations inside the damper and the dynamics of the piston valves caused by external excitation. New methods of tangling numerical discontinuities have been discussed and pressure losses have been deployed to predict the opening of the valves. The model is then validated against stringent criteria with the test-bench results and used for optimising values to obtain suitable force-velocity characteristics for integrated dynamic calculations.
Nonlinear Dynamics of Atomic Force Microscopy with Viscoelastic Term and Casimir force interactions: An Overview
Authors: Ribeiro Mauricio A. , Balthazar José Manoel , Tusset Angelo M. , Hilson  , Daum H. , Kurina Galina A. , Kirrou Ilham 
Published: December 2024

Abstract
Atomic force microscopy (AFM) is an important tool for analyzing the atomic surface of synthetic or biological samples. The atomic force microscopy device consists of a built-in microcantilever that contains a nano tip at its free end. This nano tip finds the surface of the sample which is scanned for data collection. Vibrations caused by irregularities on the sample surface are collected using a laser that reflects from the microcantilever to a photodiode. In this work, we explore the nonlinear dynamics of the mathematical model, which describes the one-dimensional torsional behavior of the microcantilever motion. The term viscoelasticity and the Casimir force were considered, and we established the set of parameters that present chaotic behavior and thus, proposed control techniques to suppress chaos. However, we explored the nonlinear dynamics behavior of a one-dimensional nonlinear AFM model with the twist of the tip of the microbeam containing the analysis tip. And so, we analyze the contribution of the Casimir Force and the viscoelasticity term in the model considered. The aim of this work was to analyze the regions in which the system is in a chaotic and periodic regime, choosing the initial conditions, using classical tools (Lyapunov Exponent, Bifurcation Diagram, Poincare Map, etc.). Determining such regions supports improvements and proposals for future control projects to suppress chaos. Such suppression allows irregularities in the movement of the microcantilever to be periodic, which can reduce noise in sample analyses.
Improving the frequency stability of capacitive ring-based Coriolis Vibrating Gyroscopes
Authors: Arifin D. , McWilliam S. 
Published: December 2024

Abstract
MEMS capacitively operated ring-based Coriolis vibratory gyroscopes are used to measure angular rate. Under standard operating conditions the ring is driven into resonance and Coriolis coupling generates a response that is proportional to the applied angular rate. In practice capacitive devices are susceptible to electrostatic nonlinearities due to narrow capacitive gaps which potentially degrades the quality of the measurement. One issue is that large amplitude drive responses yield multi-harmonic response which distorts the sense output causing the rate output to vary periodically (i.e. frequency instability). In this research it is shown that this frequency instability can be negated relatively easily by incorporating additional harmonics in the drive force. To implement such an approach it is necessary to use a voltage distribution to generate the appropriate electrostatic forces to eliminate or reduce the multi-frequency mechanical response of the ring. A mathematical model is used to quantify the effects of the implementation of the voltage distribution in terms of discrete Fourier transform of the ring response and the calculated Allan deviation. It is shown that the proposed implementation approximates linear behaviour by reducing the multi-harmonic response by orders of magnitude.
Design and characteristic analysis of quasi-zero stiffness inertial actuator
Authors: Ji Zhiyuan , Yang Tiejun , Wu Lei , Xu Yang , Li Xinhui , Zhu Minggang 
Published: December 2024

Abstract
In order to solve the problem of low frequency vibration control more effectively, a new type of inertial actuator is proposed in this paper, which is different from the conventional type in that the linear stiffness is replaced by the quasi-zero stiffness. In this design, the structure mainly consisting of a horizontal spring and connecting rod provides negative stiffness to offset the positive stiffness of the vertical spring, which not only ensures sufficient static load capacity, but also reduces the dynamic stiffness of the mass near the equilibrium position. In this study, a restoring force characteristic of the actuator (i.e., the influence of the quasi-zero stiffness structure on the mapping relationship between the restoring force and displacement) is investigated. Then the nonlinear differential equations of the quasi-zero stiffness actuator are derived. The dynamic characteristic of the actuator is discussed based on the harmonic balance method, and the accuracy is proved by numerical verification. The dynamic simulation results show that the quasi-zero stiffness structure can effectively reduce the natural frequency of the actuator, and its performance in low frequency band is better than that of the corresponding linear actuator.
An inclined beam-based vibration isolator design to attain quasi-zero-stiffness characteristics
Authors: Yadav Vinod , Jena Dibya Prakash , Pandey Sharat 
Published: December 2024

Abstract
A linear spring element combined with a nonlinear spring element has low dynamic stiffness and high static stiffness. In this work, a quasi-zero stiffness (QZS) vibration isolator based on positive stiffness and negative stiffness characteristic is explored. Using finite element simulation, the nonlinear stiffness of the inclined beam caused by the buckling effect and the linear positive stiffness of the circular arc beam is examined. The combination of these two beams delivered high static and low dynamic stiffness. The static characteristic is performed to obtain the operational displacement range. The parametric study illustrates the effect on force displacement characteristics due to variation in thickness of circular arc beam. The dynamic characteristic of the QZS isolator is studied under different damping ratio and excitation. Additionally, a stability study is carried out to identify the frequency response curve’s unstable area. Combination of inclined and circular arc beam may be a good candidate to fulfil desired requirement to achieve a wide frequency range of isolation.
The use of geometrical nonlinear local resonators to enhance the vibration control performance of metamaterial structures
Authors: Santo D R , Claeys C , Deckers E , de Oliveira L P R 
Published: December 2024

Abstract
Metamaterials has become an exciting solution for structural noise and vibration reduction in many engineering applications. Acoustic metamaterials are structures built using repetitive assemblies of identical elements to explore either Bragg-scattering or localized resonance to control mechanical waves. They present frequency bands in which waves do not freely propagate, named bandgaps, allowing acoustic and vibration attenuation at one or multiple targeted frequency ranges. If properly designed and implemented, the inclusion of a nonlinear stiffness can result in resonance frequency shifts that broaden the attenuation frequency band. This work investigates the influence of an array of lightweight nonlinear local resonators (NLR) realized via additive manufacturing on the low-frequency bandgap formation of a metamaterial beam. The NLR uses the high-static-low-dynamic stiffness (HSLDS) concept, which introduces geometric nonlinearity. The proposed model is validated through simulation and experimental analysis. The NLR results in a broadened and shifted attenuation band to lower frequencies without the necessity of adding extra mass to the resonator. This investigation contributes to understanding improvements provided by nonlinear elements for vibration control in metastructures.
Passive earthquake vibration mitigation of a steel tower crane by joint dampers
Authors: Solazzi L , Rustighi E 
Published: December 2024

Abstract
This research presents numerical findings on the seismic response of a tower crane employing anti-seismic joint dampers at its base. The study demonstrates that these damping elements effectively mitigate dynamic actions induced by seismic forces, reducing stress magnitudes by approximately 10%-15% without increasing overall displacement. Moreover, static loading configurations reveal minimal differences in mechanical behavior between cranes with and without damping elements, indicating negligible displacement increases when utilizing damping mechanisms. The research highlights the potential of damping elements to mitigate seismic effects without significantly altering the crane’s natural frequencies. Overall, the results underscore the importance of implementing damping systems to enhance seismic resilience in crane structures, promising advancements in construction safety and efficiency.
Utilising computational fluid dynamics to investigate damping effects in fluid inerter-based vibration control devices
Authors: Dogan Hakan , Tamer Aykut , Enes Salman H. , Deastra Predaricka 
Published: December 2024

Abstract
Over the past two decades, inerters have attracted significant attention in structural control. Numerous applications in engineering fields have proposed employing inerter-based control devices to mitigate structural vibrations. While theoretical studies have demonstrated performance enhancements, practical implementation and experimental validation have remained limited primarily due to cost and technical challenges. Studies conducted with the physically built inerters have showed discrepancies between theoretical model of the inerter and its actual performance because of factors such as nonlinearities and damping effects. Computational Fluid Dynamics (CFD) can provide a more accurate model of the inerter without the need for costly experimental setups. This paper presents a CFD analysis aimed at evaluating the actual performance of a fluid inerter-based control device for vibration mitigation of single degree of freedom (SDOF) structure. The accurate modeling of the inerter obtained through CFD is used to evaluate the performance of the inerter-based control device. The results reveal an important difference between vibration mitigation performance when comparing the ideal theoretical model and the CFD model.
The effect of joint uncertainty on scattering properties using a hybrid methodology
Authors: Kara M , Ferguson N S 
Published: December 2024

Abstract
Joint uncertainty is a subject of much interest in structural dynamics’ research, as joint behaviour potentially becomes more significant at higher frequencies. Therefore, an accurate determination of the scattering properties of uncertain joint elements for wave-based methods becomes more important on the subsequent prediction sensitivity. For this reason, this study examines the resulting scattering properties (reflection and transmission efficiencies) due to uncertain joints using a hybrid methodology. The scattering is calculated for a beam-to-beam joint via a combined hybrid Wave Finite Element and Finite Element (abbreviated as hybrid WFE) model, while Polynomial Chaos Expansion is utilized for the uncertainty modelling. It is assumed that the joint has a uniformly distributed uncertain thickness and loss factor. The results are compared to analytical transmission efficiencies and Monte Carlo simulations. The results show that the uncertainty in the joint does not become more evident as the frequency increases as expected, and the proposed methodology successfully models the joint uncertainty problem.
Physics-Enhanced Machine Learning: a position paper for dynamical systems investigations
Authors: Cicirello Alice 
Published: December 2024

Abstract
This position paper takes a broad look at Physics-Enhanced Machine Learning (PEML) - also known as Scientific Machine Learning - with particular focus to those PEML strategies developed to tackle dynamical systems’ challenges. The need to go beyond Machine Learning (ML) strategies is driven by: (i) limited volume of informative data, (ii) avoiding accurate-but-wrong predictions; (iii) dealing with uncertainties; (iv) providing Explainable and Interpretable inferences. A general definition of PEML is provided by considering four physics and domain knowledge biases, and three broad groups of PEML approaches are discussed: physics-guided, physics-encoded and physics-informed. The advantages and challenges in developing PEML strategies for guiding high-consequence decision making in engineering applications involving complex dynamical systems, are presented.
Vibroacoustic response of a heavy fluid loaded plate with ABH stiffeners
Authors: Martins Daniel , Karimi Mahmoud , Maxit Laurent 
Published: December 2024

Abstract
Stiffened structures are essential for a wide range of engineering applications including aeronautics, marine and rail systems. Adding stiffeners to a host structure leads to generation of Bloch-Floquet waves, which are induced by the interaction between the flexural waves in the host structure and the flexural/torsional waves in the stiffeners. These waves could generate unwanted noise and vibrations which should be mitigated. Acoustic black holes (ABHs) are widely used as a passive-control approach to mitigate vibrations of elastic structures. This study aims to use ABHs integrated as stiffeners for a fluid-loaded plate. Hence, the host structure is not modified, and its structural integrity is maintained. A heavy fluid-loaded infinite plate with periodic ABH stiffeners under a line force excitation is considered (i.e., a two-dimensional model). To obtain the vibrocoustic response, the system is modelled using the COMSOL Multiphysics®. The effectiveness of the ABH stiffeners in mitigating the vibration and noise from the fluid loaded plate is examined.
Modelling the una-corda effect in pianos
Authors: Valiente Pablo Miranda , Squicciarini Giacomo , Thompson David , Norris David O. , Hernandez Cesar 
Published: December 2024

Abstract
Most notes of a piano are fitted with two or three strings that, in normal playing conditions, are simultaneously struck by the hammer. In grand pianos, the una corda pedal offers alternative musical effects, notably a softer and duller tonal quality. This pedal’s operation is linked to a lever system that displaces the action to one side causing the hammer to hit only one-out-of-two or two-out-of-three strings, thereby altering the sound. Meanwhile, the other strings of the same note undergo sympathetic vibration, owing to their structural connection through the bridge. This paper introduces a dynamic model that replicates the effects of the una corda pedal. It consists of a state-space scheme, serving as a framework to couple the dynamic behaviour of the various components. Stiff-string models describe the strings’ vibration in three dimensions while a reduced modal model captures the dynamics of the soundboard. Results show how the string vibration and the force transmitted to the soundboard are affected by applying hammer excitation to individual or multiple strings. When all strings are struck, the transverse vibration shows beating. This effect is audible and evidenced in the spectrograms, where the amplitude of partials oscillates over time. In the una corda case, the force exerted on the bridge by the passive string increases initially with time, and its contribution to the overall transmitted force is smaller. However, there is no beating, the decay is more even, and the spectrograms do not show irregularities over time.
Numerical analysis of an omnidirectional and polarization-insensitive broadband metamaterial absorber based on a quadcopter-shaped structure
Authors: Rahman M , Soliman M M , Mansor M F , Misran N , Alam T , Sahar N B M , Islam M T 
Published: December 2024

Abstract
A broadband metamaterial absorber with a unique symmetrical quadcopter-shaped resonator, operating in the visible spectrum between 400 and 800 nm is proposed in this work for effective solar energy harvesting. A SiO2 substrate, which is likewise reinforced by a tungsten ground plane, is utilized to print this centrally symmetrical structure. Across the whole visible band, the numerical findings show an extraordinary absorption exceeding 90% while having an average absorption of 97.2%. Furthermore, the structure shows a high photothermal conversion efficiency (PTCE) across a broad temperature range in solar thermophotovoltaic (STPV) systems. Notably, strong functionality and polarization independency across a large range of incident angles, indicates its promise as an adaptable solution for developing broadband optical applications and solar cell technologies.
A broadband substrate integrated waveguide fed dielectric resonator antenna with U-slot for 5G-NR Band
Authors: Nasir Nida , Jamaluddin Mohd Haizal , Shahadan Nor Hidayu 
Published: December 2024

Abstract
In the proposed design, a Substrate Integrated Waveguide (SIW) feeding mechanism is utilized in conjunction with a higher-order mode Dielectric Resonator Antenna (DRA), which is excited by a U-slot aperture on the top side of the ground plane. This structure is aimed for 5G millimeter-wave bands, N257, and N258. Both sides of SIW are clad with 0.035mm copper with a permittivity of 2.2, Rogers 5880 is used as substrate. In contrast, DRA has a permittivity of 10. The design achieves a notable impedance bandwidth of 25-31.12 GHz (6.12 GHz or 21.8%) due to the excitation of multiple resonances of DRA modes. It delivers high gain values of 8.5 dBi at 25.8 GHz, 8.9 dBi at 27.5 GHz, and 7.2 dBi at 30 GHz, with radiation efficiency exceeding 98% within the resonance band. The radiation patterns demonstrate good co-polarized performance, validating the broadside transmission. All simulations were conducted using Ansys HFSS version 2023.