bluuebunny/crossref_metadata_2025 huggingface dataset:
Wave drag and wave patterns by ships moving in a single-file formation
Authors: Zhu Fengshen , Yuan Zhi-ming
Published: June 2024

To minimize energy expenditure for each individual, animals adopt distinctive formations, such as fish schooling, “V” formation by flying birds, and single-file formation by waterfowls. The phenomenon of ducklings following their mothers in a single-file configuration has been revealed by the mechanisms of wave-riding and wave-passing. Drawing inspiration from this phenomenon, an investigation is undertaken on ships moving in a single-file formation. The objective is to quantify how much energy can be saved in different configurations. In this study, a three-dimensional boundary element method incorporating linear free-surface boundary conditions is used to obtain the wave drag and wave patterns. It is found that when constructive wave interference occurs in a two-ship formation, the wave resistance of the trailing ship increases and the leading ship experiences a decrease in its wave drags, especially when the two ships are in close proximity. Mutual benefit arises when destructive wave interference occurs between two ships. In addition, increasing the size of the trailing vessel facilitates the effect of wave-riding by the leading ship, but this effect becomes less pronounced as the speed increases. In a multi-ship formation configuration, changing the size of the leading ship will have a localized effect on the wave-passing, but the fleet will eventually tend to a dynamic equilibrium. When the position of the first trailing vessel is changed, there is similarly a localized effect on the wave-passing. Adjusting the first trailing ship to the position of the constructive wave interference is not favorable to reducing its own drag but enhances the wave-riding effect of its close follower. Finally, to achieve wave-passing, the trailing ship does not necessarily have to occupy an optimum position. This can still be accomplished if the trailing ship moves backward by an integer multiple of wavelength.
Formation of high-power microwave dissipative soliton combs based on reactive electron–wave interaction
Authors: Yurovskiy Lev A. , Ginzburg Naum S. , Zotova Irina V. , Filchenkov Sergey E.
Published: June 2024

We theoretically demonstrate the possibility of implementing high-power repetitively pulsed microwave radiation sources based on an analogy with the formation of optical dissipative soliton combs in microresonators with Kerr nonlinearity pumped by laser radiation. A similar mechanism can arise due to electron–wave interaction in a microwave-pumped high-Q resonator when, with near-zero synchronism, detuning, amplification, and absorption are negligible, and the driving electron beam primarily acts as a medium with reactive nonlinearity. The required physical parameters are estimated for observing Ka-band dissipative soliton combs based on an undulator mechanism of electron–wave interaction in a gyrotron-pumped resonator.
Vortex-induced noise suppression of a cylinder with blowing through porous media
Authors: Maryami Reza , Guo Jing , Naseer Muhammad Rehan , Liu Yu
Published: June 2024

To mitigate vortex shedding for flow and noise control of a circular cylinder, an experimental approach combining air blowing and porous coating was implemented simultaneously as a hybrid method. Localized air blowing was symmetrically applied through structured porous media at four angles, corresponding to different regions of the flow field: boundary layers, shear layers on the cylinder, separated shear layers, and the cylinder's base. The study involved synchronizing near-field pressure fluctuation and far-field noise measurements with flow field measurements obtained via particle image velocimetry. Near-field pressure measurements were taken around the cylinder's circumference using a remote sensing method. This comprehensive investigation revealed that vortex shedding primarily induced pressure fluctuations at the cylinder's shoulders, resulting in the propagation of acoustic waves to the far field. The hybrid method, alongside the separate application of porous coating and local blowing, showcased substantial efficacy in mitigating near-field pressure, consequently leading to a reduction in far-field noise. These techniques achieved this by strategically shifting the vortex formation region further downstream and expanding the wake region compared to the baseline. Notably, the hybrid method, particularly when local blowing was applied at the base of the porous coated cylinder, exhibited a significantly enhanced impact in this regard, resembling the behavior observed with the individual application of porous coating.
A physics-informed deep learning model to reconstruct turbulent wake from random sparse data
Authors: Xie Peixing , Li Rui , Chen Yaoran , Song Baiyang , Chen Wen-Li , Zhou Dai , Cao Yong
Published: June 2024

This study develops a flexible deep learning framework aimed at reconstructing the global turbulent wakes from the randomly distributed sparse data. The framework is based on a Generative Adversarial Networks where the generator utilizes U-Net architecture and a constraint module is integrated into the training process. It is designed to overcome challenges posed by the chaotic behavior of turbulent fields, randomness in sensor layouts, and sparse sensor numbers. The efficacy of the model is validated across three high-fidelity datasets, including laminar wake behind a circular cylinder, turbulent wake behind a circular cylinder, and turbulent wake behind a square cylinder. The proposed model demonstrates the ability to accurately reconstruct flow patterns of both turbulent and laminar wakes, even utilizing merely 0.043% of the data from the target flow field. The proposed model exhibits significant generalization capability, which means that the model has a nearly independence from the distributions of sensors and a robust adaptation across the inputs with unseen sensor numbers. Ablation studies elucidate the distinct and complementary roles of each module within the model. Additionally, the behavior of the bottleneck tensor is analyzed through visualization, including comparisons with the lift coefficient, quantitative analyses and dimensionality reduction. These visualizations confirm the ability of the model to extract distinctive phase information reliably from sparse data, thereby guiding the reconstruction of global flow patterns. These findings highlight the potential of the model for applications in fluid dynamics where data is collected in a variable manner.
Numerical investigation of the influence of different barrel lengths on the interior ballistic process within an underwater submerged launch
Authors: Sun Zhiqun , Li Qiang , Qu Pu , Lu Lin
Published: June 2024

Although underwater submerged launching has been rigorously investigated for decades, there remains a dearth of comprehensive understanding regarding the underwater interior ballistic characteristics for varying barrel lengths. To address this knowledge gap, the present study aims to explore, via numerical simulations, the initial velocity of interior ballistics, projectile drag, and the mechanism of initial flow field formation at the muzzle under various barrel lengths, thereby considering the influence of differing barrel lengths. The five distinct lengths of barrels are expressed as dimensionless ratios of the weight of water column in front of the projectile to the weight of the projectile in order to be more general. Five different ratios of water-to-projectile weight are investigated: 1.0, 1.2, 1.5, 1.8, and 2.0, all possessing identical diameters and evaluated under equivalent launch conditions. Different ratios significantly impact muzzle velocity, with shorter barrels yielding higher muzzle velocities, while ensuring complete propellant combustion. Further investigations indicate that variations in drag constitute the fundamental cause of initial velocity changes. Furthermore, it is observed that barrels of different lengths exhibit identical characteristics at the point of maximum drag. The initial flow field at the muzzle exhibits considerable variations in terms of length, profile dimensions, and intensity. The findings of this study offer valuable insights into exploring the mechanism of submerged launching and will be utilized to investigate the optimal barrel length.
An approach for multiscale two-phase flow simulation in the direct simulation Monte Carlo framework
Authors: Shin Yeongho , Kim Sanghun , Jun Eunji
Published: June 2024

To simulate multiscale gas flow with solid particles, Burt's model, based on the Direct Simulation Monte Carlo (DSMC) framework, is widely used to predict gas–solid interactions under the assumption of a negligibly small solid particle diameter compared to the local gas mean free path. However, Burt's model could become inaccurate when the solid particle is large relative to the local gas mean free path. This study introduces the Gas–Solid Synchronous (GSS) model, which predicts gas–solid interactions in continuum gas regions without assuming the local gas flow regime around a solid particle. Similar to Burt's model, the GSS model includes gas-to-solid and solid-to-gas interaction models to consider bidirectional interaction between two phases. The GSS gas-to-solid model is established by selecting accurate semi-empirical force and heat transfer models in comparison with DSMC simulation results. The GSS solid-to-gas model is developed based on the principles of momentum and energy conservation and validated against Burt's solid-to-gas model. The results show that Burt's model could overestimate the interphase force and heat transfer rates when its assumption on solid particle diameter does not hold, but it can reproduce non-equilibrium characteristics of two-phase flows where gas velocity distribution functions do not follow the Maxwell–Boltzmann distribution. By contrast, the GSS model can accurately predict gas–solid interaction in continuum gas flows, while it cannot capture the non-equilibrium nature of two-phase flows. The characteristics and limitations of the two models indicate that using a valid model for each gas–solid interaction could be crucial for accurate simulation of multiscale two-phase flows.
Effects of temperature and CO2 concentration on the early stage nucleation of calcium carbonate by reactive molecular dynamics simulations
Authors: Qin Ling , Yang Junyi , Bao Jiuwen , Sant Gaurav , Wang Sheng , Zhang Peng , Gao Xiaojian , Wang Hui , Yu Qi , Niu Ditao , Bauchy Mathieu
Published: June 2024

It is significant to investigate the calcium carbonate (CaCO3) precipitation mechanism during the carbon capture process; nevertheless, CaCO3 precipitation is not clearly understood yet. Understanding the carbonation mechanism at the atomic level can contribute to the mineralization capture and utilization of carbon dioxide, as well as the development of new cementitious materials with high-performance. There are many factors, such as temperature and CO2 concentration, that can influence the carbonation reaction. In order to achieve better carbonation efficiency, the reaction conditions of carbonation should be fully verified. Therefore, based on molecular dynamics simulations, this paper investigates the atomic-scale mechanism of carbonation. We investigate the effect of carbonation factors, including temperature and concentration, on the kinetics of carbonation (polymerization rate and activation energy), the early nucleation of calcium carbonate, etc. Then, we analyze the local stresses of atoms to reveal the driving force of early stage carbonate nucleation and the reasons for the evolution of polymerization rate and activation energy. Results show that the higher the calcium concentration or temperature, the higher the polymerization rate of calcium carbonate. In addition, the activation energies of the carbonation reaction increase with the decrease in calcium concentrations.
Experimental study on the hypersonic double incident shock wave/boundary layer interaction regulated by plasma actuation array
Authors: Yang Hesen , Liang Hua , Yang Bo , Zong Haohua , Li Jinping , Zhang Dongsheng , Xiong Youde , Wu Yun , Li Yinghong
Published: June 2024

In the inlet passage of a hypersonic vehicle, multi-channel shock waves inevitably interact with the boundary layer, producing complex multi-channel shock wave/boundary layer interactions (SWBLIs). The flow separation caused by these interactions significantly decreases the intake efficiency and may prevent the intake from starting. The typical interaction mode of multi-channel interactions is through double incident SWBLIs. Therefore, it is necessary to study the characteristics of double incident SWBLIs and identify relevant flow control techniques. In this paper, the characteristics of hypersonic double incident SWBLIs are first examined, and then the results of an experimental study on regulation using a plasma actuation array are reported. We find that plasma actuation can positively regulate the hypersonic double incident SWBLI, and the optimal control effect reduces the area of the separation bubble by 38.62%. The main regulation mechanism involves suppressing the low-frequency instability of SWBLIs through a high-frequency shock effect. The regional scale of the separation bubble can be controlled by regulating the shock wave oscillation range. Correlative results provide technical and method support for the application of plasma actuation in hypersonic double incident SWBLI regulation and present a new idea for the selection of flow control methods for advanced intake systems.
Full factorial analysis of gradual switching in thermally oxidized memristive devices
Authors: Stasner P. , Hennen T. , Gorbunova E. , Garcia Munoz A. , Waser R. , Wouters D. J.
Published: June 2024

Memristive devices are promising candidates for synaptic memories in neuromorphic computing systems, but the insufficient reliability of the analog behavior has been a challenge. Lateral oxide scaling with bottom-up technologies such as thermal oxidation, coupled with new device architectures, can improve the reliability. However, the effect of thermal oxide growth on analog device behavior remains unclear. In this study, we fabricate a variety of resistive switching thermal oxides on tantalum electrode surfaces and develop a method for rapid full factorial electrical analysis. The analysis uses 2500 unique control parameter combinations of current limits and RESET-stop-voltages to compare device behavior across millions of modulated current–voltage sweeps. We clarify the mechanisms that shift the device behavior from abrupt towards gradual SET transitions, a desirable characteristic for emulating analog plasticity. We found that a mildly negative differential resistance and an increased internal series resistance at the metal–oxide interface contribute to the stabilization of the gradual SET transitions. These findings highlight the importance of fine-tuning the bottom-up oxide growth for improving switching performance.
The development of the QM/MM interface and its application for the on-the-fly QM/MM nonadiabatic dynamics in JADE package: Theory, implementation, and applications
Authors: Huang Haiyi , Peng Jiawei , Zhang Yulin , Gu Feng Long , Lan Zhenggang , Xu Chao
Published: June 2024

Understanding the nonadiabatic dynamics of complex systems is a challenging task in computational photochemistry. Herein, we present an efficient and user-friendly quantum mechanics/molecular mechanics (QM/MM) interface to run on-the-fly nonadiabatic dynamics. Currently, this interface consists of an independent set of codes designed for general-purpose use. Herein, we demonstrate the ability and feasibility of the QM/MM interface by integrating it with our long-term developed JADE package. Tailored to handle nonadiabatic processes in various complex systems, especially condensed phases and protein environments, we delve into the theories, implementations, and applications of on-the-fly QM/MM nonadiabatic dynamics. The QM/MM approach is established within the framework of the additive QM/MM scheme, employing electrostatic embedding, link-atom inclusion, and charge-redistribution schemes to treat the QM/MM boundary. Trajectory surface-hopping dynamics are facilitated using the fewest switches algorithm, encompassing classical and quantum treatments for nuclear and electronic motions, respectively. Finally, we report simulations of nonadiabatic dynamics for two typical systems: azomethane in water and the retinal chromophore PSB3 in a protein environment. Our results not only illustrate the power of the QM/MM program but also reveal the important roles of environmental factors in nonadiabatic processes.
Taxonomic reassessment of Scabies (Bivalvia: Unionidae) species in China based on multilocus and mitogenomic phylogenetic analyses
Authors: Dai Yu-Ting , Chen Zhong-Guang , Hu Cheng-Lin , Ning Peng-Fei , Ouyang Shan , Huang Xiao-Chen , Wu Xiao-Ping
Published: June 2024

Effective species conservation necessitates the ability to accurately differentiate among species, a challenge compounded by taxonomic uncertainties in freshwater mussels due to substantial intraspecific variation and pronounced phenotypic plasticity in shell morphology. The taxonomic status and species validity of Scabies longata and S. chinensis, two species endemic in China, have been under continuous debate since establishment. The lack of essential molecular data required for a comprehensive systematic study has resulted in the unresolved taxonomic status of these two species. This study presents molecular data, including COI barcoding, COI + 28S rRNA, and mitogenomic data combined with morphological characteristics to assess the validity of S. longata and S. chinensis. Both morphological and COI barcoding data support the conclusion that S. longata and S. chinensis are junior synonyms of Nodularia douglasiae and N. nuxpersicae respectively. Our findings suggest the absence of Scabies species in China. Mitochondrial phylogenetic analyses were used to further elucidate intrageneric relationships within the genus Nodularia, revealing the following relationships: (N. breviconcha (Nodularia sp. 1 (N. douglasiae (N. nuxpersicae, N. nipponensis)))). We underscore the significance of employing an integrated taxonomic approach for species identification, especially given the considerable morphological disparities between larvae and adult freshwater mussels. Proper morphological identification of adult specimens is essential for extracting meaningful taxonomic characters. Furthermore, our findings suggest a notable resemblance between the freshwater bivalve fauna in southern China and those east of the Mekong River. ZooBank: urn:lsid:zoobank.org:pub:DA87D330-5E23-4F4B-8CC2-CBA3CD191BE8
Expression of transforming growth factor β signalling molecules and their correlations with genes in loci linked to polycystic ovary syndrome in human foetal and adult tissues
Authors: Azumah Rafiatu , Hummitzsch Katja , Anderson Richard A. , Rodgers Raymond J.
Published: June 2024

Context Altered signalling of androgens, anti-Müllerian hormone or transforming growth factor beta (TGFβ) during foetal development have been implicated in the predisposition to polycystic ovary syndrome (PCOS) in later life, aside from its genetic predisposition. In foetal ovarian fibroblasts, TGFβ1 has been shown to regulate androgen signalling and seven genes located in loci associated with PCOS. Since PCOS exhibits a myriad of symptoms, it likely involves many different organs. Aims To identify the relationships between TGFβ signalling molecules and PCOS candidate genes in different tissues associated with PCOS. Methods Using RNA sequencing data, we examined the expression patterns of TGFβ signalling molecules in the human ovary, testis, heart, liver, kidney, brain tissue, and cerebellum from 4 to 20 weeks of gestation and postnatally. We also examined the correlations between gene expression of TGFβ signalling molecules and PCOS candidate genes. Key results TGFβ signalling molecules were dynamically expressed in most tissues prenatally and/or postnatally. FBN3, a PCOS candidate gene involved in TGFβ signalling, was expressed during foetal development in all tissues. The PCOS candidate genes HMGA2, YAP1, and RAD50 correlated significantly (P < 0.01) with most TGFβ signalling molecules in at least four foetal tissues, and specifically with TGFBR1 in six out of the seven tissues examined. Conclusions This study suggests that possible crosstalk occurs between genes in loci associated with PCOS and TGFβ signalling molecules in multiple tissues, particularly during foetal development. Implications Thus, alteration in TGFβ signalling during foetal development could affect many tissues contributing to the multiple phenotypes of PCOS in later life.
Americans harbor much less favorable explicit sentiments toward young adults than toward older adults
Authors: Francioli Stéphane P. , Shakeri Angela , North Michael S.
Published: June 2024

Public and academic discourse on ageism focuses primarily on prejudices targeting older adults, implicitly assuming that this age group experiences the most age bias. We test this assumption in a large, preregistered study surveying Americans’ explicit sentiments toward young, middle-aged, and older adults. Contrary to certain expectations about the scope and nature of ageism, responses from two crowdsourced online samples matched to the US adult population (
N
= 1,820) revealed that older adults garner the most favorable sentiments and young adults, the least favorable ones. This pattern held across a wide range of participant demographics and outcome variables, in both samples. Signaling derogation of young adults more than benign liking of older adults, participants high on SDO (i.e., a key antecedent of group prejudice) expressed even less favorable sentiments toward young adults—and more favorable ones toward older adults. In two follow-up, preregistered, forecasting surveys, lay participants (
N
= 500) were generally quite accurate at predicting these results; in contrast, social scientists (
N
= 241) underestimated how unfavorably respondents viewed young adults and how favorably they viewed older adults. In fact, the more expertise in ageism scientists had, the more biased their forecasts. In a rapidly aging world with exacerbated concerns over older adults’ welfare, young adults also face increasing economic, social, political, and ecological hardship. Our findings highlight the need for policymakers and social scientists to broaden their understanding of age biases and develop theory and policies that ponder discriminations targeting all age groups.
Path-dependence of the Plio–Pleistocene glacial/interglacial cycles
Authors: Carrillo Judit , Mann Michael E. , Larson Christopher J. , Christiansen Shannon , Willeit Matteo , Ganopolski Andrey , Li Xueke , Murphy Jack G.
Published: June 2024

We find strong path dependence in the evolution of the Plio–Pleistocene glaciations using CLIMBER-2 Earth System Model simulations from the mid-Pliocene to modern preindustrial (3 My-0 My BP) driven by a gradual decrease in volcanic carbon dioxide outgassing and regolith removal from basal ice interaction. Path dependence and hysteresis are investigated by alternatively driving the model forward and backward in time. Initiating the model with preindustrial conditions and driving the model backward using time-reversed forcings, the increase in volcanic outgassing back-in-time (BIT) does not generate the high CO2 levels and relatively ice-free conditions of the late Pliocene seen in forward-in-time (FIT) simulations of the same model. This behavior appears to originate from nonlinearities and initial state dependence in the carbon cycle. A transition from low-amplitude sinusoidal obliquity (~41 ky) and precession (~23 ky) driven glacial/interglacial cycles to high-amplitude ~100 ky likely eccentricity-related sawtooth cycles seen between −1.25 My and −0.75 My BP (the Mid-Pleistocene transition or “MPT”) in FIT simulations disappears in BIT integrations depending on the details of how the regolith removal process is treated. A transition toward depleted regolith and lowered atmospheric CO2 levels are both required to reproduce the MPT.
Successful use of anti-CD19 CAR T cells in severe treatment-refractory stiff-person syndrome
Authors: Faissner Simon , Motte Jeremias , Sgodzai Melissa , Geis Christian , Haghikia Aiden , Mougiakakos Dimitrios , Borie Dominic , Schroers Roland , Gold Ralf
Published: June 2024

Treatment with autologous chimeric antigen receptor (CAR) T cells has emerged as a highly effective approach in neuroimmunological disorders such as myasthenia gravis. We report a case of successful anti-CD19 CAR T cell use in treatment-refractory stiff-person syndrome (SPS). To investigate clinical and immunological effects of anti-CD19 CAR T cell use in treatment-refractory SPS, a 69-y-old female with a 9-y history of treatment-refractory SPS with deteriorating episodes of stiffness received an infusion of autologous anti-CD19 CAR T cells (KYV-101) and was monitored clinically and immunologically for more than 6 mo. CAR T cell infusion resulted in reduced leg stiffness, drastic improvement in gait, walking speed increase over 100%, and daily walking distance improvement from less than 50 m to over 6 km within 3 mo. GABAergic medication (benzodiazepines) was reduced by 40%. KYV-101 CAR T cells were well tolerated with only low-grade cytokine release syndrome. This report of successful use of anti-CD19 CAR T cells in treatment-refractory SPS supports continued exploration of this approach in SPS and other B cell–related autoimmune disorders.
Examining the role of distributional information and structural types
in multiword sequence processing by Chinese preschool children
Authors: Wang Lu , Yu Wenbo , Peng Yiran , Liang Dandan
Published: June 2024

Multiword sequences (MWSs) are units between words and
sentences, which can help people to achieve native-like proficiency in a
language. However, the extent to which Chinese native (L1) speakers, especially preschool
children in the midst of language development, comprehend and process MWSs
remains uncertain. While previous research has primarily focused on the
distributional properties of MWSs, whether Chinese preschool children exhibit
sensitivity to the distributional information of MWSs requires further
examination. In addition, the potential influence of structural types on such
sensitivity has received limited attention. This study examined Chinese
preschool children’s sensitivity to distributional information and structural
types of MWSs when processing Mandarin MWSs. Participants performed an
imitating-production task. Linear mixed-effects models revealed that children
were sensitive to two types of distributional information of MWSs: MWS frequency
and MWS contingency. Intriguingly, no evidence was found to suggest sensitivity
to the structural types of MWSs. Furthermore, the findings demonstrated not only
the continuous effects of MWS frequency and contingency but also an interaction
between these two factors. This study thus indicates that during the processing
of MWSs, the performance of Chinese preschool children is influenced by the
distributional information of MWSs while remaining unaffected by structural
types.
Edge smoothness enhancement of digital lithography based on the DMDs collaborative modulation
Authors: Zhang Jingya , Luo Ningning , Chen Deyuan
Published: June 2024

The rough saw-tooth edge caused by the inherent microstructures of digital micromirror device (DMD) will reduce the quality of the lithography pattern. Comprehensively considering the manufacturing efficiency, precision and cost, we propose a DMDs collaborative modulation lithography method to improve the smoothness of the lithography pattern edge. Through combining two misaligned DMDs to collaboratively modulate exposure dose, the better edge smoothness can be achieved. Collaborative exposure with 1/2 DMD pixel misalignment and 1/4 DMD pixel misalignment are both implemented to form the step-shape lithography patterns. The experimental results show that the saw-tooth edge can approximate to a straight line when increasing the number of times of the collaborative exposure. Further error analysis indicates it is effective to improve the edge smoothness while ensuring the lithography quality by using the collaborative modulation lithography. These results indicate that the DMDs collaborative modulation lithography is a promising technique for fabrication of microstructures, which may be a solution for balancing the fabrication precision, efficiency and cost.
Boson bloom
Authors: Baskaran G , May A R
Published: June 2024

The year 2024 marks the 100th anniversary of the first article on Bose statistics. Bose breathed life into the Planck distribution of radiation by a microscopic derivation (Bose 1924Z. Phys.26178), adding a new insight, namelyindistinguishabilityinto the then evolving quantum theory. Einstein recognized the importance of this article and got it published. Using Bose statistics Einstein wrote an article on the theory (Einstein 1924Sutzungsber. Preuss. Akad. Wiss Phys.-Math Kl.261) of an ideal Bose gas and Bose–Einstein condensation. The groundbreaking discovery of Bose, an unveiling of a secret of quantum mechanics, continues to reverberate after a century. Bose’s paper is considered the fourth important paper in old quantum theory, following Planck’s (1900) article (Planck 1900Verh. Disch Phys. Ges.2202), Einstein’s (1905) photoelectric effect (Einstein 1905Ann. Phys., Lpz.17132) and Bohr’s model (1913) of the atom (Bohr 1913London, Edinburgh Dublin Phil. Mag. J. Sci.261). Dirac (1926Proc. R. Soc.A112661) coined the namebosonfor one of the two families of indistinguishable particles, the other family being fermion. The edifice of modern quantum field theory, many-body quantum theory, quantum-information and quantum-computing are built on bosons, fermions and anyons. The ever-blooming quantum garden of bosons has photons, gluons, W-bosons, mesons, Higgs-bosons, gravitons, phonons, magnons, excitons, plasmons, polaritons and so on. We present a brief historical account of Bose’s life and his discovery, followed by a bird’s eye view of the impacts of bosons in modern science and technology: from Bose’s distribution of 3-degree background radiation reaching us in the form of cosmic microwave background from the big bang era toboson sampling, a novel quantum computing method.

Bosogenesis before Baryogenesis?: And God said, Let there be light: and there was light (Genesis, 1:4)
Enhanced cation ordering, electron-spin-phonon interactions and Fano resonance in half-metallic Sr2FeMoO6 thin films
Authors: Yadav Ekta , Sahoo Jayaprakash , Mavani Krushna R
Published: June 2024

We report the presence of electron-spin-phonon interactions in half-metallic ferromagnetic Sr2FeMoO6 (SFMO) double perovskite thin films using temperature-dependent Raman spectroscopy. A series of SFMO thin films have been prepared on LaAlO3 (001) single-crystal substrate using the Pulsed Laser Deposition technique. These depositions have been made in different gas-conditions such as in vacuum, and under nitrogen and oxygen gas pressures. At room temperature, Raman spectra manifest a Fano feature which indicates the presence of electron-phonon coupling in the films. The electron-phonon coupling strength further changes with a change in deposition conditions. Magnetization results show that the SFMO film grown in vacuum has the highest saturation magnetization which suggests better cation ordering as compared to the other films. For enhanced understanding, Raman spectra were recorded at varied temperatures and the data were analyzed by theoretical model fittings. A parameter quantifying temperature-dependent anharmonic nature of phonons has been derived using Balkanski model fits. This parameter shows a drastic deviation in the vicinity of Curie temperatures, manifesting a spin-phonon coupling in SFMO films. We further show that the spin-phonon coupling strengthens with improved Fe–Mo ordering. Any experimental observation of spin-phonon coupling has not been reported for SFMO systems till date. The magnetization data corroborate well with these observations made by Raman measurements. Our results of Raman spectroscopy, magnetization and resistivity collectively suggest that the SFMO films exhibit electron-spin-phonon interactions, which are influenced by the cation ordering. We also devised out the method of relating the anharmonic nature of Raman modes with the degree of Fe–Mo ordering and spin-phonon coupling in double-perovskite materials.
Modelling laser modified secondary electron yield response of surfaces
Authors: Din Amin A , Uren Robin , Wackerow Stefan , Fontenla Ana T P , Pfeiffer Stephan , Tabares Elisa G , Zolotovskaya Svetlana , Abdolvand Amin
Published: June 2024

Electron clouds hinder the operation of particle accelerators. In the Large Hadron Collider (LHC), the copper beam screens are located within close proximity to the beam path, resulting in beam-induced electron multipacting, which is the main source of electron cloud formation. Conditions for multipacting are encountered when such surfaces have a secondary electron yield (SEY) greater than unity. Roughening the surface through laser processing offers an effective solution for reducing secondary electrons. Laser ablation leaves behind a complex rough, multi-scale geometrical surface with an altered chemical composition. Current models often over-simplify the geometry, do not have sufficient experimental data to derive input parameters, and exclude SEY-reducing mechanisms such as the surface chemistry. Leading to electron-matter interactions which do not resemble that of a real surface. Here, this complex surface is studied on copper used in the LHC, and the influence of microgeometry, inhomogeneous nanostructure and complex surface chemistry on the SEY is investigated. A novel, improved model is proposed that characterises these sophisticated structures, enabling the efficient design of surfaces to reduce SEY. To validate the model, samples were made using a variety of laser parameters. Modelling insights revealed that secondary electron suppression is not only caused by the microgeometry but also the nanostructure and chemical modification play a role. Contrary to the conventional theory, high aspect ratio structures are not necessarily required for effective SEY reduction. Currently, the model is applicable to a variety of surface morphologies and could be employed for other materials.
The effect of bending angle on a flexible electrode DBD plasma under sinusoidal excitation
Authors: Li Jiayin , Zhou Desheng , Rebrov Evgeny , Tang Xin , Kim Minkwan
Published: June 2024

There is a critical demand for sophisticated surface disinfection and sterilization devices accessible to the public by using cold atmospheric pressure air plasmas. A flexible printed circuit design of a dielectric barrier discharge reactor under non-bending and two bending configurations with an angle of 120° and 180° was studied. The characteristics of power consumption, the optical emission spectrum, dynamic process, electrode temperature and ozone concentration are evaluated. The non-bending configuration produces more O3, as compared to the bending configuration at the same applied voltage. The 180° configuration has a maximum concentration of excited species at the expense of higher electrode temperature. Both bending configurations demonstrated the propagation of filaments to bending axis where the continues luminescence is observed due to the high electrical field. The energy efficiency for plasma-generated reactive species reaches to 40% for non-bending configuration and decreases with the increase of bending angle. This research provides a new strategy for perspective into the plasma generated reactive species in biomedical and environmental applications.
Search for charged lepton flavor violation of vector mesons in the U(1)
X
SSM
Authors: Dong Xing-Xing , Zhao Shu-Min , Dong Bo-Wei , Huo Jia-Peng , Guo Cai , Feng Tai-Fu
Published: June 2024

Charged lepton flavor violation (CLFV) represents a clear new physics (NP) signal beyond the standard model (SM). In this work, we investigate the CLFV decays of vector mesons

V
→

l

i

±

l

j

∓

with V ∈ {ϕ, J/Ψ, ϒ(1S), ϒ(2S), ϒ(3S)} in the U(1)
X
SSM. Considering the SM-like Higgs boson mass within 3σ region and the experimental upper bounds of Br(l

j
→ l

i

γ), we discuss the corresponding constraints on the relevant parameter space of the model. From the numerical analyses, the CLFV sources originated from the non-diagonal elements correspond to the initial and final generations of the leptons. And the branching ratios to these CLFV processes can easily reach the present experimental upper bounds, which indicate that this model can produce significant contributions to such CLFV decays. Therefore, searching for CLFV processes of vector mesons may be an effective channel to study NP.
Research on features and localization of AE signals from the mechanical body of industrial robots based on WD-EMD
Authors: Dong Shishang , You Jun , Li Ming , Gong Shi , Zhang Hao , Qiao Shuai , Zhang Xin , Guo Li , Yuan Xuechao
Published: June 2024

In order to reveal the propagation characteristics of acoustic emission (AE) signals in the body of industrial machinery, the characteristic frequencies and wave speeds of AE signals propagated on the interior and exterior surfaces (IS and ES) of the body were extracted. Subsequently, an algorithm utilizing characteristic frequency and time difference of arrival (TDOA) is proposed for the identification and localization of AE sources. Initially, an AE source is induced on the IS and ES of the body using the pencil-lead break method in accordance to ASTM standards, and the AE signal is captured by two piezoelectric sensors at a sampling frequency of 3 MHz. Then, to avoid the limitations of wavelet decomposition using self-selected wavelet scale and the problem that a single indicator cannot properly evaluate the correlation between independent mode functions (IMFs) with the original signal, this paper will conduct 4-layer wavelet decomposition of the original signal according to the response frequency range of the sensor, and select the wavelet details within the stable range of the response frequency of the sensor for preliminary reconstruction,and then the empirical mode decomposition (EMD) method is used to decompose the de-noised AE signal into 7 IMFs, and the AE waveform is reconstructed by the combined information of correlation coefficient and variance accounted for. Secondly, the reconstruction method combined with EMD analysis and a single index is compared with the proposed method in this paper to verify the reliability of the proposed method. In addition, the frequency domain characteristics of AE signal propagation process on the IS and ES of the body are extracted. Finally, based on the TDOA principle, the propagation speed of AE signal on the IS and ES of the body is calculated. Based on the geometric relationship between the AE source and two sensors, an algorithm for the location of the AE source is proposed. The results show that the proposed signal reconstruction method can effectively extract the features of AE signals, and the average positioning accuracy of the localization algorithm based on characteristic frequency and TDOA reaches 0.86%.
A high sensitivity digital giant magneto-impedance (GMI) sensor for magnetic communication
Authors: Xu Miao , Traore Papa Silly , Asfour Aktham
Published: June 2024

A high sensitivity Magneto-Impedance (GMI) sensor for magnetic communication systems in harsh environments is presented. In this system, the receiving coil of a conventional magnetic communication system is replaced by a high sensitivity GMI sensor and its digital electronic conditioning as well as digital signal processing. The whole architecture of the sensor is described in detail. It achieves two digital amplitude demodulations to recover, in real time, the binary sequence of the message sent by the transmitter. The demonstration and the validation of the reliable functioning of the system are illustrated through the transmission of messages using On-Off-Keying modulation method. The measured equivalent magnetic noise of the sensor was about noise

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at 60 kHz, which is largely lower than the noise of other potential types of magnetic sensors such as Anisotropic Magneto-Resistive sensors for this application. This noise level suggests a potential higher communication range. When compared with an inductive coil, the developed sensor also presented an almost flat and sufficiently wide bandwidth compatible with magnetic communication. This bandwidth could potentially be extended according to the application.
DRLSTM-DA: a novel aeroengine remaining useful life prediction method based on deep optimization of multiple sensors information
Authors: Suo Shiwei , Fu Song , Lin Lin , Zhang Sihao , Liu Yikun , Hu Guolei , Hu Changsheng
Published: June 2024

One of the crucial tasks in Remaining useful life prediction is to effectively extract key sensor information from numerous sensor signals. In this article, a novel dual-attention enhanced deep residual LSTM (DRLSTM-DA) is developed to deeply optimize multidimensional sensor signals. First, two LSTM layers are designed to compress and reconstruct representative degradation information from input multidimensional time series data, to generate a new feature space. Second, a novel channel adaptive soft threshold module is designed to assign different weights according to the importance of different sensor information, and simultaneously eliminate the noise information in the signal. Thirdly, a temporal attention mechanism is designed to automatically highlight moments containing important decay information while suppressing unimportant moments. Finally, compared with other SOTA methods, our architecture achieves RMSE of 11.55, 13.74, 11.25, and 14.19 on four sub-datasets of the C-MAPSS dataset, with scores of 234.24, 465.49, 202.23, and 537.66, respectively. Meanwhile, in real aeroengine operation dataset, our architecture achieved the smallest RMSE (8.62). These results all validate the good predictive performance of our model.
Iterative Laplace of Gaussian filter and improved Teager energy operator for bearing fault detection in gearboxes
Authors: Yang Na , Liu Yie , Wei Yu , Feng Kezhu
Published: June 2024

The presence of cyclic impulses is considered to be a significant indicator of bearing defects. The extraction of fault-related information from gearboxes, however, poses a significant challenge due to the complex working conditions in gear transmission systems. These conditions often lead to fault-related impulse features being masked by inevitable background noise and vibration components. To address this issue, a novel iterative Laplace of Gaussian (LoG) filtering technique is proposed for the fault diagnosis field of bearings in gearboxes. An objective function incorporating Kurtosis statistics is used to iteratively update LoG coefficients instead of relying on fixed coefficients as in the original version, making the iterative LoG filtering technique better suited for handling fault-induced impact signals. Furthermore, an improved Teager energy operator (TEO) is developed to reduce the susceptibility of the original TEO to noise. The improvement involves incorporating a multi-resolution symmetric difference sequence into the discrete expression of TEO. This symmetric difference acts as a translation-invariant, sliding-window filter that, when combined with an energy operator, enables both energy detection and frequency filtering. The robustness against noise and sensitivity to frequency can be further improved by adjusting the multi-resolution parameter. The results of the experiments confirm the effectiveness of the proposed approach in identifying weak bearing fault features for gearboxes. Besides, the proposed method is also compared with the original LoG filter-based method and some competing methods, demonstrating its superior performance.
Deformation mechanism of the dual thermo-sensitive hydrogel bilayer structure
Authors: Jiang Huilong , Lei Jincheng , Liu Zishun
Published: June 2024

Thermo-sensitive hydrogel is a smart soft material that undergoes significant volume deformation in response to temperature changes, making it highly applicable in soft smart actuators. However, traditional thermo-sensitive hydrogel bilayer structures are often characterized by slow response rates and limited unidirectional bending capabilities. To overcome these limitations, a new thermo-sensitive hydrogel bilayer structure with faster response and bidirectional deformation is proposed in this work. This structure consists of two active thermo-sensitive hydrogel layers with different thermo-sensitive effect, in which one shrinks and the other swells when the temperature changes. The hydrogels with the fastest temperature response are identified by optimizing the monomer fraction and used to create the bilayer structure. The deformation states of the dual thermo-sensitive hydrogel bilayer structure are controlled by regulating the phase state of the both layers, resulting in different deformation patterns under varied temperature in experiments. We have established a model to describe the deformation of the bilayer structure. Finally, the capability of the bilayer structure to mimic human body movements and the blooming and wilting of flowers is demonstrated. This work reveals the deformation mechanism for a novel dual thermo-sensitive hydrogel bilayer structure, which holds great significance for the advancement of soft smart actuators.
Influence of the preparation method (thermal quench, ball-milling, dehydration and freeze-drying) on the dynamical properties of glassy trehalose
Authors: Decressain R , Carpentier L
Published: June 2024

Dielectric relaxation measurements have been performed on the glassy states of trehalose reached using different routes of amorphisation: thermal quench of the liquid state, milling of the anhydrous crystalline form, freeze-drying and dehydration of the dihydrate crystalline form. This study has revealed that all the glassy states are characterized by two relaxation processes respectively attributed to the slow Johari-Goldstein mode and to fast secondary intramolecular relaxations. These sub-Tg secondary relaxations are however strikingly different in the four glassy states revealing different energy landscape topologies.