bluuebunny/crossref_metadata_2025_split huggingface dataset:
Validation of MAPS: a novel 6-degree-of-freedom position sensor for nanopositioning
Authors: Aras Richard , Dallas James , Heaps Edward , Varga László , Yacoot Andrew 
Published: June 2024

Abstract
Anemos’ multi-dimensional absolute position sensors (MAPS) consists of a photolithographically defined reference scale, a camera, and computer image processing that decodes the relative position of a camera to the scale. A series of experiments tested the novel opto-electronic sensor against traceable National Physical Laboratory optical interferometers (OI) with motion provided by nanopositioning stages. Initially, MAPS to OI agreement was verified to be within 5 nm in the lateral (XY) axes across 100 μm travel. However, when MAPS, OI, and stage position were correlated across much finer steps, MAPS demonstrated repeatability and noise below 100 pm, indicating that the larger discrepancies seen previously were due to Abbe effects, servo-mechanical, and other OI/MAPS-extrinsic factors. In a third experiment, the outputs of four orthogonally placed MAPS 6-degree-of-freedom (6DoF) sensors were correlated against each other, OI, and feedback from a single-axis stage. Here, MAPS displayed sub-nanometre agreement with other sensors, and consistency across independent MAPS sensors. A fourth experiment collected millions of MAPS sample points during repetitive 1 nm circular motion. Spectral analysis of these large datasets, correlations between noise in multiple axes and repeatability indicate MAPS may resolve single digit picometre movements. These results corroborate simulations and supports the feasibly of million-to-one position interpolation from the MAPS 5 μm-grid reference scale. This equates to an unprecedented 40-bit dynamic range since MAPS can sustain measurement resolution over metres of travel. Overall, the experimental series highlight the challenges of nanoscale calibration and benefit of full 6DoF sensing in real-world nano-positioning systems.
Joint moments of higher order derivatives of CUE characteristic polynomials II: structures, recursive relations, and applications
Authors: Keating Jonathan P , Wei Fei 
Published: June 2024

Abstract
In a companion paper (Keating and Wei 2023 Int. Math. Res. Not.
2024 9607–32), we established asymptotic formulae for the joint moments of higher order derivatives of the characteristic polynomials of CUE random matrices. The leading order coefficients of these asymptotic formulae are expressed as partition sums of derivatives of determinants of Hankel matrices involving I-Bessel functions, with column indices shifted by Young diagrams. In this paper, we continue the study of these joint moments and establish more properties for their leading order coefficients, including structure theorems and recursive relations. We also build a connection to a solution of the σ-Painlevé III

′

equation. In the process, we give recursive formulae for the Taylor coefficients of the Hankel determinants formed from I-Bessel functions that appear at zero and find some differential equations these determinants satisfy. The approach we establish is applicable to determinants of general Hankel matrices whose columns are shifted by Young diagrams.
Transport characteristic evaluation of runaway electrons in an ITER disruption simulation
Authors: Liu Shi-Jie , Wang Feng , Hu Di , Wang Zheng-Xiong ,   the JOREK team
Published: June 2024

Abstract
In previous studies, it has been observed that the transport of energetic electrons decreases with increasing energy. This observation is a global and long-time-scale result, attributed to the space-averaged perturbations. In this work, we focus on the local and instantaneous transport characteristics of runaway electrons (REs) during the phase of tokamak disruption, with REs speeds close to the speed of light. To simulate the dynamics of REs, we utilize a particle tracing code called PTC. By coupling PTC with the MHD code JOREK, we are able to study the energy and spatial dependence of RE transport. Our investigations reveal that the finite orbit width (FOW) effect plays an important role in RE transport. This effect is influenced by the relative direction of the electron drift and the magnetic field line. Specifically, the FOW effect strengthens the transport when the drift direction aligns with the deflecting direction of the field line. And we compare the transport profiles among three time slices: at the beginning of the thermal quench, during the thermal quench, and at the beginning of the current quench. In this ITER disruption simulation, the perturbation scale is strong and

δ
B

/

B

is up to 0.05 at developed thermal quench stage. It is reasonable that the influence of FOW effect on transport is less than that of magnetic perturbation even if the energy of REs is about hundreds MeV and the orbit width is equal to or greater than the perturbation length. These analyses provide insights into the mechanisms of RE transport based on magnetic perturbations.
Turbulence generation in the solar corona through nonlinear interaction between 3D kinetic Alfvén wave and magnetic islands
Authors: Patel Garima , Uma R , Sharma R P 
Published: June 2024

Abstract
This study investigates the interaction between kinetic Alfvén waves (KAWs) and magnetic islands in solar corona region. KAWs and magnetic islands are believed to be one of the key players in the heating of the coronal plasma and particle acceleration. We have used the dynamical model for KAWs to simulate its propagation through magnetic islands. The equation is solved numerically by using the finite difference and pseudospectral technique for spatial and temporal variations. The simulation results have been studied and signatures of turbulent structures evolving with time have been observed. Turbulence plays a considerable role in tapping out magnetic energy to thermal energy. The plot of the energy spectrum as a function of wavenumber exhibits a power law behavior in the inertial range, characterized with an exponent around

−
5

/

3

. Beyond this range, the spectrum becomes steeper. In order to gain a more thorough knowledge of the physical processes that underlie the development of localized structures and to estimate the current sheet scale sizes, a semi-analytically model is also performed. The results indicate that the size of localized structures are comparable to ion gyro-radius, and different intensities of KAW further modify this length scale formed at different times. The purpose of the study is to acquire an understanding of the KAW propagation in magnetic islands and the way it contributes to the formation of turbulence and energy release in the solar corona. A comparative aspect of the non-linear interaction of 3D KAW with magnetic island and null point is also presented which shows that non-linear interaction of 3D KAW with null point, leads to rapid disorganization of the magnetic field and the creation of localized structures.
Online meta-learning approach for sensor fault diagnosis using limited data
Authors: Wang Lei , Huang Dukang , Huang Ke , Civera Marco 
Published: June 2024

Abstract
The accurate and timely diagnosis of sensor faults plays a critical role in ensuring the reliability and performance of structural health monitoring (SHM) systems. However, the challenge is detecting, locating, and estimating sensor faults in an online manner using limited training data. To resolve this problem, a novel approach for online sensor fault diagnosis is proposed for SHM. The proposed approach is based on meta-learning, which enables superior model generalization capabilities using limited data. The detection, localization, and estimation of typical sensor faults in an online manner can be achieved efficiently by the proposed approach. First, a one-dimensional convolutional neural network (1D CNN) is designed to detect and locate faulty sensors. The initial model parameters of the 1D CNN are optimized using a model-agnostic meta-learning training strategy. This strategy allows the acquisition of transferable prior knowledge, which can speed up the learning process on new sensor fault detection and localization tasks. The meta-learning strategy also enables efficient and accurate detection and localization of potential faulty sensors with limited data. After detecting and locating the faulty sensors, an online updating algorithm based on a dual Kalman filter is used to estimate the severity of sensor faults and structural states simultaneously. The proposed approach is demonstrated with simulated sensor faults that cover a numerical example and field measurements from the Canton Tower. The results show that the proposed approach is applicable for online sensor fault diagnosis in SHM.
A piezoelectric pump with composite chamber: using bluff body to improve its anti-clogging ability
Authors: Chen Song , Fang Xuan , Xie Yilei , Huang Zijian , Zhan Weijun , Kan Junwu , Zhang Zhonghua , Li Jianping 
Published: June 2024

Abstract
Piezoelectric pumps are widely used in biomedicine, chip cooling, fuel cells and so on. However, existing valve-based piezoelectric pumps suffer from the problem of easy clogging. In order to solve the problem, a piezoelectric pump with composite chamber (PPCC) is proposed. The composite chamber, consisting of drive chamber and flow chamber, which provides the PPCC with excellent output performance by amplifying the compression ratio. Meanwhile, a bluff body is set in the drive chamber, and the vortex flow around the bluff body is able to adsorb air bubbles and other impurities, preventing impurities from entering the drive chamber, the bluff body provides the PPCC with strong anti-clogging ability. Multi-physics field simulation is established, which verifies the PPCC is feasible. The fluid inside the pump chamber is simulated, and it is concluded that the 90-arc bluff body is optimal, favoring the formation of high-speed vortices. Furthermore, a prototype is fabricated and experimentally investigated. The experimental results show that the PPCC has excellent performance in pumping liquid and gas. At 300Vpp, the PPCC delivered a maximum flow rate of 235.9 ml min−1 for air and 24.07 ml min−1 for water. The anti-clogging ability of PPCC is verified through bubble resistance experiments, which demonstrates the composite chamber and bluff body effectively prevent foreign impurities from entering the drive chamber. The PPCC provides a new approach to microfluidic pumping devices.
Collimated beam formation in 3D acoustic sonic crystals
Authors: Vanel A L , Dubois M , Tronche C , Fu S , Wang Y-T , Dupont G , Rakić A D , Bertling K , Abdeddaim R , Enoch S , Craster R V , Li G , Guenneau S , Perchoux J 
Published: June 2024

Abstract
We demonstrate strongly collimated beam formation, at audible frequencies, in a three-dimensional acoustic phononic crystal where the wavelength is commensurate with the crystal elements; the crystal is a seemingly simple rectangular cuboid constructed from closely-spaced spheres, and yet demonstrates rich wave phenomena acting as a canonical three-dimensional metamaterial. We employ theory, numerical simulation and experiments to design and interpret this collimated beam phenomenon and use a crystal consisting of a finite rectangular cuboid array of

4
×
10
×
10

polymer spheres 1.38 cm in diameter in air, arranged in a primitive cubic cell with the centre-to-centre spacing of the spheres, i.e. the pitch, as 1.5 cm. Collimation effects are observed in the time domain for chirps with central frequencies at 14.2 kHz and 18 kHz, and we deployed a laser feedback interferometer or Self-Mixing Interferometer – a recently proposed technique to observe complex acoustic fields—that enables experimental visualisation of the pressure field both within the crystal and outside of the crystal. Numerical exploration using a higher-order multi-scale finite element method designed for the rapid and detailed simulation of 3D wave physics further confirms these collimation effects and cross-validates with the experiments. Interpretation follows using High Frequency Homogenization and Bloch analysis whereby the different origin of the collimation at these two frequencies is revealed by markedly different isofrequency surfaces of the sonic crystal.
Monogamy of quantum correlations shared in a cavity-freeoptomechanical system
Authors: Hmouch Jamila , Amazioug Mohamed , Nassik Mostafa 
Published: June 2024

Abstract
In this work, we discuss the monogamy property of quantum correlations (entanglement and steering) distributed in a cavity-free optomechanical system. In a tripartite pure Gaussian state, we verify the hierarchy of the studied quantum correlations. We investigate in detail the CKW-type monogamy inequalities, based on Gaussian Rényi-2 entropy entanglement, as well as, Gaussian steering. We quantify genuine tripartite entanglement by using the minimum residual Gaussian entanglement. In addition, we consider the minimum residual Gaussian steering as a quantifier of genuine tripartite steering. Our results indicate that, in the one-mode versus two-mode Gaussian state, the correlations hierarchy was respected; in the considered pure state, the monogamy of entanglement and steering distribution was proven and the studied genuine tripartite correlations have similar time evolution under the same conditions.
Optical intensity figures of merit of insulator-metal-insulator and metal-insulator-metal thin-film stacks
Authors: Raşeev Georges 
Published: June 2024

Abstract
This paper discusses the quality factors Q and the intensity figures of merit (IFoM) evaluating the intensity and leakage of modes of the reflection flux and of the plane-wave and locally excited transmitted fluxes of insulator-metal-insulator (IMI) and metal-insulator-metal (MIM) 2D planar thin-film stacks, here air-Au-glass and air-Au-SiO2-Au-glass stacks respectively. These thin film stacks sustain a single surface plasmon polariton (SPP) and multiple planar waveguide (PWG) modes. The Q and IFoM of the 3D dispersion graph (in-plane wave vector k

ρ
/k
0 ∈ [0, 1.52]/frequency ω ∈ [0.5, 2.7] eV/observable dispersion) are calculated and analyzed along 2D cuts where either the in-plane wave vector k

ρ
/k
0 or the frequency ω are varied the other independent variable being kept fixed. Here these two cuts are called spatial (ω fixed) and frequency (k

ρ
/k
0 fixed) domains. Due to a lower leakage, the Q and IFoM of the IMI and MIM thin film stack modes are significantly larger in the spatial domain than in the frequency domain. In the spatial domain the IMI and MIM stack modes dominate at low and high frequencies respectively. In the frequency domain, the Q and IFoM of a MIM stack mode is always larger than that of an IMI stack. Our results span a large domain of frequencies in the SPP and RPP region and of the in-plane wave vector whereas the results in the literature presented above concern only particular laser frequencies and limited in-plane wave vector values. Our Q and IFoM of the 2D planar thin film stack modes, obtained with optimized independent variables, are larger than those of other planar thin film stacks but smaller than some 2D/3D nano scale samples with an involved geometry. The simplicity of producing these simple IMI and MIM stacks permit their use in the applications.
Design and development of a first order reversal curve measurement enabled variable temperature vibrating sample magnetometer
Authors: Pratheek  , Badiger Hanamanta , Sah Nutan Kumari , Joshi Rajeev S , Bhat Subray V , Hegde Balachandra G 
Published: June 2024

Abstract
In this paper we present the design, construction and calibration of a sensitive vibrating sample magnetometer (VSM) and temperature variable setup with a capability to measure magnetization of magnetic materials from 100 K to 400 K with First Order Reversal Curve (FORC) measurement facility. It uses a bipolar power supply to energize an electromagnet capable of attaining ±1 Tesla field, subwoofer speaker for vibrating the sample and the induced voltage in four coil setup is measured by a lock-in amplifier. All hardware is controlled by a customized LabView program. The cryostat is designed such that the temperature can be varied continuously from 100 K to 400 K using liquid nitrogen up to room temperature and forced nitrogen gas/air for high temperatures study. We report here the VSM sensitivity of up to 10−2 emu/gm and can measure much weaker signals. The FORC protocol in this system is implemented via a dedicated virtual instrument in LabView capable of magnetic field reversal and termination at appropriate point to study domain nucleation field. The detailed analysis of the data is done using the open-source resources. We present the FORC measurement for Co0.5Zn0.5Fe2O4, a ferrimagnet. To establish the sensitivity of the instrument we present the results of magnetization measurement with temperature and phase transition study of La0.4Ca0.6MnO3 and La0.75Sr0.25MnO3.
Extended rubber-elasticity model for non-Gaussian isotropic hyperelasticity of polyelectrolyte hydrogels undergoing curl-to-stretch transition
Authors: Shi Weilin , Lu Haibao , Fu Yong-Qing 
Published: June 2024

Abstract
The nature of extremely high stretchability in hydrogels with a non-Gaussian elasticity has been extensively investigated. However, there are few studies on curl-to-stretch transitions of condensed polymer networks in polyelectrolyte hydrogels and their non-Gaussian hyperelasticity. In this study, an extended rubber-elasticity model was developed to investigate different mechanical behaviors, e.g., S-shaped and J-shaped stress-elongation ratio curves, where the condensed polymer networks in polyelectrolyte hydrogels undergo a curl-to-stretch transition and present a non-Gaussian isotropic hyperelasticity. A free-energy equation was formulated to describe the curl-to-stretch transitions and their thermomechanical conformations of condensed polymer networks, based on the free energy functions of elasticity, electrostatics and hydrophobicity. A constitutive relationship between stress and elongation ratio was then proposed to describe the non-Gaussian isotropic hyperelasticity in polyelectrolyte hydrogels, and effects of segment number, charged segment fraction and salt concentration on the mechanical behaviors were studied. Moreover, a segmental length criterion of condensed polymer networks was proposed to distinguish the S-shaped and J-shaped stress-elongation ratio curves. Finally, experimental data reported in literature were applied to verify the effectiveness of the proposed theoretical models. This study aims to provide a new thermomechanical criterion for non-Gaussian isotropic hyperelasticity in polyelectrolyte hydrogels undergoing the curl-to-stretch transition.
Analytical and numerical calculation of the effect of edge states of the Kane-Mele model on the RKKY interaction
Authors: Alsayyid Y , Ahmadi J , Soltani M , Rashedi G 
Published: June 2024

Abstract
In this paper, we investigate the Kane-Mele model and endeavor to demonstrate, through analytical calculations, how the presence of topological edge states influences the RKKY interaction. We illustrate that the effect diminishes as one moves away from the edges. To facilitate our analytical approach, we initially utilize a one-dimensional wire exhibiting linear dispersion for each spin as an approximation to the Kane-Mele model. We examine its impact on the RKKY interaction. Subsequently, we establish a correspondence between the edge states of the Kane-Mele model and a one-dimensional quantum wire model, wherein the coupling strength diminishes with increasing distance from the edges. Finally, we compare the analytical results with numerical findings obtained using the Landauer-Buttiker formulation.
Influence of temperature-dependent density inhomogeneity on the stability of atmospheric stratified fluids
Authors: Kaladze T D , Misra A P 
Published: June 2024

Abstract
The stability of atmospheric stratified fluids is revisited to study the influence of the temperature-dependent density inhomogeneity due to thermal expansion in the Earth’s lower atmosphere (with heights 0 to 50 km) under the action of gravity. Previous theory in the literature [Phys. Lett. A 480 (2023) 128 990] is modified and advanced. It is found that the Brunt-Väisälä frequency associated with internal gravity waves is modified, leading to new instability conditions of vertically stratified fluids. The possibility of the onset of Rayleigh-Bénard convective instability is also discussed, and the influences of the modified Brunt-Väisälä frequency and the density and temperature gradients on the instability growth rates are studied.
Bose–Einstein distribution temperature features of quasiparticles around magnetopolaron in Gaussian quantum wells of alkali halogen ions
Authors: Zhang 张 Xin 鑫 , Sarengaowa 萨 仁高娃 , Han 韩 Shuang 爽 , An 安 Ran 然 , Zhang 张 Xin-Xue 新雪 , Ji 纪 Xin-Ying 新颖 , Jiang 江 Hong-Xu 红旭 , Ma 马 Xin-Jun 新军 , Li 李 Pei-Fang 培芳 , Sun 孙 Yong 勇 
Published: June 2024

Abstract
We have applied strong coupling unitary transformation method combined with Bose–Einstein statistical law to investigate magnetopolaron energy level temperature effects in halogen ion crystal quantum wells. The obtained results showed that under magnetic field effect, magnetopolaron quasiparticle was formed through the interaction of electrons and surrounding phonons. At the same time, magnetopolaron was influenced by phonon temperature statistical law and important energy level shifts down and binding energy increases. This revealed that lattice temperature and magnetic field could easily affect magnetopolaron and the above results could play key roles in exploring thermoelectric conversion and conductivity of crystal materials.
Towards electrophysiological measurement of presence in virtual reality through auditory oddball stimuli
Authors: Savalle Emile , Pillette Léa , Won Kyungho , Argelaguet Ferran , Lécuyer Anatole , J-M Macé Marc 
Published: June 2024

Abstract

Objective. Presence is an important aspect of user experience in virtual reality (VR). It corresponds to the illusion of being physically located in a virtual environment (VE). This feeling is usually measured through questionnaires that disrupt presence, are subjective and do not allow for real-time measurement. Electroencephalography (EEG), which measures brain activity, is increasingly used to monitor the state of users, especially while immersed in VR. Approach. In this paper, we present a way of evaluating presence, through the measure of the attention dedicated to the real environment via an EEG oddball paradigm. Using breaks in presence, this experimental protocol constitutes an ecological method for the study of presence, as different levels of presence are experienced in an identical VE. Main results. Through analysing the EEG data of 18 participants, a significant increase in the neurophysiological reaction to the oddball, i.e. the P300 amplitude, was found in low presence condition compared to high presence condition. This amplitude was significantly correlated with the self-reported measure of presence. Using Riemannian geometry to perform single-trial classification, we present a classification algorithm with 79% accuracy in detecting between two presence conditions. Significance. Taken together our results promote the use of EEG and oddball stimuli to monitor presence offline or in real-time without interrupting the user in the VE.