bluuebunny/crossref_metadata_2025 huggingface dataset:
Drawing the line: public attitudes towards warranted and unwarranted government surveillance in European countries
Authors: Školník Milan , Haman Michael
Published: April 2024

This article investigates public attitudes towards government surveillance for law enforcement and national security in different European countries, considering the broader context of citizens' security concerns. These concerns encompass crime within individual countries, potential terrorist attacks, activities of foreign agents, and even inter-state conflicts, such as the Russian Federation's military aggression against Ukraine. Using data from the International Social Survey Programme, we examine opinions about various types of government surveillance. Regression analysis is employed to determine which variables influence these opinions. Notably, there is a tangible hesitation among citizens regarding such surveillance, stemming from fears of privacy invasion and potential misuse of collected data. Our findings indicate greater support for government surveillance in Western and Nordic countries compared to post-Communist countries. Respondents with a comprehensive understanding of political issues and those advocating for government spending on security generally held a more positive view of government surveillance rights. On the other hand, perceptions of higher corruption were linked to negative views on surveillance.
Computational and experimental microfluidics: Total analysis system for mixing, sorting, and concentrating particles and cells
Authors: Coral David , Attard Matthew , Pedrol Eric , Solé Rosa Maria , Díaz Francesc , Aguiló Magdalena , Mateos Xavier
Published: April 2024

Body fluids can potentially indicate the presence of non-small cancer cells. Studying these fluids is an emerging field that could be crucial for cancer detection and monitoring treatment effectiveness. Meanwhile, the examination of fluids on a microscopic level is part of the field of microfluidics. This study focuses on the development of a total analysis system that consists of various interconnected structures that are designed to mix, classify, concentrate, and isolate particles in fluids that mimic the behavior of cancer and normal cells. Using the COMSOL Multiphysics software, the device's performance was optimized to use a pressure input of 35 kPa for water or serum and 29.4 kPa for a mixture of liquid and serum samples, which are the optimal pressure inputs. The numerical models were validated by experiments using two types of polystyrene particles, with diameters of 5 and 20 μm. Moreover, the developed system was applied to monitor the behavior of red blood cells. The microfluidic chip is capable of addressing several challenges through visual detections, including mixing tests of two fluids with similar densities, proper particle size classification using Dean flow fractionation, and single-step recovery of large, labeled particles. Finally, the collected particles were examined using an environmental scanning electron microscope to determine their size, and the results demonstrated that successful size separation was achieved, with particles around 20 μm completely separated from the smaller ones.
An experimental platform for investigation of the Zeeman effect in strong magnetic fields
Authors: Huerta N. A. , Minaker Z. J. , Ivanov V. V. , Mancini R. C. , Swanson K. J. , Hariharan H. K.
Published: April 2024

An experimental platform is developed for the investigation of the Zeeman effect in strong magnetic fields. Mega-Gauss magnetic fields are generated by a 1 MA Zebra pulsed power machine using metal rod loads. A gas jet or CH oil on the load is the source of hydrogen. Excited hydrogen atoms are backlit by black body radiation from the rod load. Hydrogen absorption spectra are recorded with a grating spectrometer and intensified gated CCD camera. The experimental platform enables the observation of the quadratic Zeeman effect in hydrogen gas jets using the spectral shift of the central line in the Zeeman triplet. Other gases can be studied using the gas jet method.
Self-adjoint momentum operator for a particle confined in a multi-dimensional cavity
Authors: Mariani A. , Wiese U.-J.
Published: April 2024

Based on the recent construction of a self-adjoint momentum operator for a particle confined in a one-dimensional interval, we extend the construction to arbitrarily shaped regions in any number of dimensions. Different components of the momentum vector do not commute with each other unless very special conditions are met. As such, momentum measurements should be considered one direction at a time. We also extend other results, such as the Ehrenfest theorem and the interpretation of the Heisenberg uncertainty relation to higher dimensions.
New spinorial mass-quasilocal angular momentum inequality for initial data with marginally future trapped surface
Authors: Kopiński Jarosław , Soria Alberto , Valiente Kroon Juan A.
Published: April 2024

We prove a new geometric inequality that relates the Arnowitt–Deser–Misner mass of initial data to a quasilocal angular momentum of a marginally outer trapped surface (MOTS) inner boundary. The inequality is expressed in terms of a 1-spinor, which satisfies an intrinsic first-order Dirac-type equation. Furthermore, we show that if the initial data is axisymmetric, then the divergence-free vector used to define the quasilocal angular momentum cannot be a Killing field of the generic boundary.
Design and application research of portable reversible thermochromic patches in grid power supply systems
Authors: Liu He , Jiao Lixin , Lin Haidan , Li Lina
Published: April 2024

This study aims to develop a novel portable reversible thermochromic patch and evaluate its potential applications in temperature monitoring and indication. The film is based on the concept of electronic charge transfer thermochromic coatings, enabling accurate detection of high temperatures. Experimental results demonstrate that when the temperature of the monitored device’s circuit reaches 70 °C or above, the color of the film changes from deep blue to colorless, indicating potential overheating in the power grid. Using salt spray corrosion testing and cycle performance testing, we validate the film’s excellent corrosion resistance in harsh natural environments and its provision of reliable color indication. The film possesses portability and ease of attachment to various electrical devices and circuits requiring temperature sensing. By connecting the color information of the film to a computer system, we can achieve digital temperature monitoring, providing potential applications in future smart grid development.
Design and verification of a new non-contact piezoelectric energy harvester based on a sinusoidal exciting mechanism
Authors: Li Jie , Qi Ji , Wang Liang
Published: April 2024

In this paper, a new non-contact rotary piezoelectric energy harvester based on a sinusoidal exciting mechanism has been proposed. The energy transformation is realized in a non-contact form. The sinusoidal orbital rotor can act as a sinusoidal excitation to the contacts, and it can avoid damage to piezoelectric ceramics from direct strikes while bending piezoelectric cantilever beams. After a series of experiments, the prototype demonstrated an excellent output performance. Having explored the influence of the rotation speed on the output voltage, it reaches the peak when the rotation speed is 180 rpm and the maximum voltage is 18.6 V. The relationship between power and voltage was validated with the rise of resistance at the optimum speed. When the resistance is 10 kΩ, the power that arrives at the peak is 1.35 mW, and the maximum voltage is 12.1 V when the resistance is 200 kΩ. Some application experiments have been designed and verify the feasibility of the prototype; it can light up 18 LEDs and power some microelectronic equipment.
Particle topology-regulated relaxation dynamics in cluster-ordering
Authors: Xue Binghui , Liufu Wei , Yin Jiafu , Yang Junsheng , Yin Panchao
Published: April 2024

The granular materials of soft particles (SPs) demonstrate unique viscoelasticity distinct from general colloidal and polymer systems. Exploiting dynamic light scattering measurements, together with molecular dynamics simulations, we study the diffusive dynamics of soft particle clusters (SPCs) with spherical and cylindrical brush topologies, respectively, in the melts of SPs. A topologically constrained relaxation theory is proposed by quantitatively correlating the relaxation time to the topologies of the SPCs, through the mean free space (Va) of tethered SPs in the cluster. The tethered SPs in SPCs are crowded by SPs of the melts to form the cage zones, and the cooperative diffusion of the tether SPs in the zones is required for the diffusive motion of SPCs. The cage zone serves as an entropic barrier for the diffusion of SP clusters, while its strength is determined by Va. Three characteristic modes can be confirmed: localized non-diffusive mode around critical Va, diffusive mode with Va deviating far from the critical value, and a sub-diffusive mode as an interlude between two limits. Our studies raise attention to the emergent physical properties of materials based on SPs via a topological design while opening new avenues for the design of soft structural materials.
Modeling transient edge plasma transport with dynamic recycling
Authors: Smirnov R. D. , Umansky M. V. , Krasheninnikov S. I.
Published: April 2024

The work presents numerical simulation studies of the role that dynamic plasma recycling on the main wall and divertor target surfaces plays in transient edge plasma transport phenomena, such as edge localized modes (ELMs). The studies are performed by coupling the edge plasma transport code UEDGE [Rognlien et al., J. Nucl. Mater. 196–198, 347 (1992)] and the wall reaction–diffusion transport code FACE [Smirnov et al., Fusion Sci. Technol. 71, 75 (2017)]. The two-dimensional, time-dependent, two-way coupling of the codes, in a realistic tokamak geometry, is accomplished using the Integrated Plasma Simulator framework [Elwasif et al., in 18th Euromicro Conference on Parallel, Distributed and Network-Based Processing (PDP 2010), Pisa, Italy (IEEE, 2010), pp. 419–427] for all modeled material plasma boundaries. The simulations show that dynamic plasma recycling has substantially different characteristics on the main wall and on the divertor plates. It is demonstrated that during an ELM cycle the outer wall can dynamically absorb and release a number of particles comparable to that expelled by the ELM from the core plasma, by far exceeding the dynamic retention capacity of the divertor surfaces. The resulting evolution of the edge and divertor plasma conditions during an ELM cycle is analyzed.
Defect control strategies for Al1−xGdxN alloys
Authors: Lee Cheng-Wei , Din Naseem Ud , Yazawa Keisuke , Nemeth William , Smaha Rebecca W. , Haegel Nancy M. , Gorai Prashun
Published: April 2024

Tetrahedrally bonded III-N and related alloys are useful for a wide range of applications from optoelectronics to dielectric electromechanics. Heterostructural AlN-based alloys offer unique properties for piezoelectrics, ferroelectrics, and other emerging applications. Atomic-scale point defects and impurities can strongly affect the functional properties of materials, and therefore, it is crucial to understand the nature of these defects and the mechanisms through which their concentrations may be controlled in AlN-based alloys. In this study, we employ density functional theory with alloy modeling and point defect calculations to investigate native point defects and unintentional impurities in Al1−xGdxN alloys. Among the native defects that introduce deep midgap states, nitrogen vacancies (VN) are predicted to be in the highest concentration, especially under N-poor growth conditions. We predict and experimentally demonstrate that VN formation can be suppressed in thin films through growth in N-rich environments. We also find that Al1−xGdxN alloys are prone to high levels of unintentional O incorporation, which indirectly leads to even higher concentrations of deep defects. Growth under N-rich/reducing conditions is predicted to minimize and partially alleviate the effects of O incorporation. The results of this study provide valuable insights into the defect behavior in wurtzite nitride-based alloys, which can guide their design and optimization for various applications.
Plasmon–emitter coupling in cytosine-rich hairpin DNA-templated silver nanoclusters: Thermal reversibility, white light emission, and dynamics inside live cells
Authors: Chakraborty Subhajit , Pramanik Srikrishna , Shekhar Shashi , Mukherjee Saptarshi
Published: April 2024

Bio-templated luminescent noble metal nanoclusters (NCs) have attracted great attention for their intriguing physicochemical properties. Continuous efforts are being made to prepare NCs with high fluorescence quantum yield (QY), good biocompatibility, and tunable emission properties for their widespread practical applications as new-generation environment-friendly photoluminescent materials in materials chemistry and biological systems. Herein, we explored the unique photophysical properties of silver nanoclusters (AgNCs) templated by cytosine-rich customized hairpin DNA. Our results indicate that a 36-nucleotide containing hairpin DNA with 20 cytosine (C20) in the loop can encapsulate photostable red-emitting AgNCs with an absolute QY of ∼24%. The luminescent properties in these DNA-templated AgNCs were found to be linked to the coupling between the surface plasmon and the emitter. These AgNCs exhibited excellent thermal sensitivity and were employed to produce high-quality white light emission with an impressive color rendering index of 90 in the presence of dansyl chloride. In addition, the as-prepared luminescent AgNCs possessing excellent biocompatibility can effectively mark the nuclear region of HeLa cells and can be employed as a luminescent probe to monitor the cellular dynamics at a single molecular resolution.
A review on flow instability in hydro-viscous drive
Authors: Cui Jianzhong , Tang Hui
Published: April 2024

Hydro-viscous drive (HVD) plays a significant role in smoothly transferring torque and flexibly regulating the velocity of the disks. By hydro-viscous drive, we mean that the viscous shear stress of the thin oil film between a multi-layer assembly of rotating parallel disks is generated to transmit torque and power. The laminar-to-turbulent transition is an extremely complicated issue due to the combined effects of squeeze and shear on the oil film within the microscale friction pair system. Hence, a comprehensive and thorough analysis of flow instability in fluid-thermal-solid interaction of tribodynamic behavior is highly desirable. Following a brief introduction of fundamentals of HVD, this paper provides an overall review on the instability mechanisms for three types of canonical flow dynamic models, i.e., plane squeeze flow, plane shear flow, and rotating-disk flow. The effects of various aspects of wall conditions and working media, such as surface microstructure, and temperature-dependent viscosity, on flow instability are then summarized, which can serve as a reference and guidance for optimizing the design of friction pair systems. Based on the review of the former progress, this paper not only explores the in-depth mechanisms regarding the laminar-to-turbulent transition in microchannel flow, but also provides the possibility of bridging the gap between flow instability and tribodynamic behavior.
Enhanced thermal conductivity of epoxy resin by incorporating three-dimensional boron nitride thermally conductive network
Authors: Wang Xubin , Zhang Changhai , Zhang Tiandong , Tang Chao , Chi Qingguo
Published: April 2024

Packaging insulation materials with high thermal conductivity and excellent dielectric properties are favorable to meet the high demand and rapid development of third generation power semiconductors. In this study, we propose to improve the thermal conductivity of epoxy resin (EP) by incorporating a three-dimensional boron nitride thermally conductive network. Detailedly, polyurethane foam (PU) was used as a supporter, and boron nitride nanosheets (BNNSs) were loaded onto the PU supporter through chemical bonding (BNNS@PU). After immersing BNNS@PU into the EP resin, EP-based thermally conductive composites were prepared by vacuum-assisted impregnation. Fourier transform infrared spectrometer and scanning electron microscope were used to characterize the chemical bonding and morphological structure of BNNS@PU, respectively. The content of BNNS in BNNS@PU/EP composites was quantitatively analyzed by TGA. The results show that the thermal conductivity of the BNNS@PU/EP composites reaches 0.521 W/m K with an enhancement rate η of 30.89 at an ultra-low BNNS filler content (5.93 wt. %). Additionally, the BNNS@PU/EP composites have excellent dielectric properties with the frequency range from 101 to 106 Hz. This paper provides an interesting idea for developing high thermal conductivity insulating materials used for power semiconductor packaging.
Optical and electronic properties of BCN films deposited by magnetron sputtering
Authors: Liu Caiyun , Chen Le , Yin Hong
Published: April 2024

Boron carbonitride (BCN) films containing hybridized bonds involving B, C, and N over wide compositional ranges enable an abundant variety of new materials, properties, and applications; however, their electronic performance is still limited by the presence of structural and electronic defects, yielding sluggish mobility and electrical conductivity. This work reports on mechanically stable BCN films and their corresponding optical and electronic properties. The ternary BCN films consisting of hybridized B–C–N bonds have been achieved by varying N2 flow by the radio frequency magnetron sputtering method. The BCN films show a bandgap value ranging from 3.32 to 3.82 eV. Hall effect measurements reveal an n-type conductivity with an improved hall mobility of 226 cm2/V s at room temperature for the optimal film. The n-BCN/p-Si heterojunctions exhibit a nonlinear rectifying characteristic, where the tunneling behavior dominates the injection regimes due to the density of defects, i.e., structural disorder and impurities. Our work demonstrates the tunable electrical properties of BCN/Si p–n diodes and, thus, is beneficial for the potential application in the fields of optics, optoelectronics, and electrics.
Observing heroic behavior and its influencing factors in immersive virtual environments
Authors: Jin Kelou , Wu Jie , Zhang Ran , Zhang Shen , Wu Xiaoyan , Wu Tingting , Gu Ruolei , Liu Chao
Published: April 2024

Studying heroism in controlled settings presents challenges and ethical controversies due to its association with physical risk. Leveraging virtual reality (VR) technology, we conducted a three-study series with 397 participants from China to investigate heroic actions. Participants unexpectedly witnessed a criminal event in a simulated scenario, allowing observation of their tendency to physically intercept a thief. We examined situational factors (voluntariness, authority, and risk) and personal variables [gender, impulsivity, empathy, and social value orientation (SVO)] that may influence heroism. Also, the potential association between heroism and social conformity was explored. In terms of situational variables, voluntariness modulated participants’ tendency to intercept the escaping thief, while perceived risk demonstrated its impact by interacting with gender. That is, in study 3 where the perceived risk was expected to be higher (as supported by an online study 5), males exhibited a greater inclination toward heroic behavior compared to females. Regarding other personal variables, the tendency to engage in heroic behavior decreased as empathy levels rose among males, whereas the opposite trend was observed for females. SVO influenced heroic behavior but without a gender interaction. Finally, an inverse relationship between heroism and social conformity was observed. The robustness of these findings was partly supported by the Chinese sample (but not the international sample) of an online study 4 that provided written descriptions of VR scenarios, indicating cultural variations. These results advance insights into motivational factors influencing heroism in the context of restoring order and highlight the power of VR technology in examining social psychological hypotheses beyond ethical constraints.
Bmal1 integrates circadian function and temperature sensing in the suprachiasmatic nucleus
Authors: Hoekstra Marieke M. B. , Ness Natalie , Badia-Soteras Aina , Brancaccio Marco
Published: April 2024

Circadian regulation and temperature dependency are important orchestrators of molecular pathways. How the integration between these two drivers is achieved, is not understood. We monitored circadian- and temperature-dependent effects on transcription dynamics of cold-response protein RNA Binding Motif 3 (Rbm3). Temperature changes in the mammalian master circadian pacemaker, the suprachiasmatic nucleus (SCN), induced Rbm3 transcription and regulated its circadian periodicity, whereas the core clock gene Per2 was unaffected. Rbm3 induction depended on a full Brain And Muscle ARNT-Like Protein 1 (Bmal1) complement: reduced Bmal1 erased Rbm3 responses and weakened SCN circuit resilience to temperature changes. By focusing on circadian and temperature dependency, we highlight weakened transmission between core clock and downstream pathways as a potential route for reduced circadian resilience.
Structural insights into the regulation of protein-arginine kinase McsB by McsA
Authors: Arifuzzaman Md , Kwon Eunju , Kim Dong Young
Published: April 2024

In gram-positive bacteria, phosphorylated arginine functions as a protein degradation signal in a similar manner as ubiquitin in eukaryotes. The protein-arginine phosphorylation is mediated by the McsAB complex, where McsB possesses kinase activity and McsA modulates McsB activity. Although
mcsA
and
mcsB
are regulated within the same operon, the role of McsA in kinase activity has not yet been clarified. In this study, we determined the molecular mechanism by which McsA regulates kinase activity. The crystal structure of the McsAB complex shows that McsA binds to the McsB kinase domain through a second zinc-coordination domain and the subsequent loop region. This binding activates McsB kinase activity by rearranging the catalytic site, preventing McsB self-assembly, and enhancing stoichiometric substrate binding. The first zinc-coordination and coiled-coil domains of McsA further activate McsB by reassembling the McsAB oligomer. These results demonstrate that McsA is the regulatory subunit for the reconstitution of the protein-arginine kinase holoenzyme. This study provides structural insight into how protein-arginine kinase directs the cellular protein degradation system.
Tight-packing of large pilin subunits provides distinct structural and mechanical properties for the
Myxococcus xanthus
type IVa pilus
Authors: Treuner-Lange Anke , Zheng Weili , Viljoen Albertus , Lindow Steffi , Herfurth Marco , Dufrêne Yves F. , Søgaard-Andersen Lotte , Egelman Edward H.
Published: April 2024

Type IVa pili (T4aP) are ubiquitous cell surface filaments important for surface motility, adhesion to surfaces, DNA uptake, biofilm formation, and virulence. T4aP are built from thousands of copies of the major pilin subunit and tipped by a complex composed of minor pilins and in some systems also the PilY1 adhesin. While major pilins of structurally characterized T4aP have lengths of <165 residues, the major pilin PilA of
Myxococcus xanthus
is unusually large with 208 residues. All major pilins have a conserved N-terminal domain and a variable C-terminal domain, and the additional residues of PilA are due to a larger C-terminal domain. We solved the structure of the
M. xanthus
T4aP (T4aP
Mx
) at a resolution of 3.0 Å using cryo-EM. The T4aP
Mx
follows the structural blueprint of other T4aP with the pilus core comprised of the interacting N-terminal α1-helices, while the globular domains decorate the T4aP surface. The atomic model of PilA built into this map shows that the large C-terminal domain has more extensive intersubunit contacts than major pilins in other T4aP. As expected from these greater contacts, the bending and axial stiffness of the T4aP
Mx
is significantly higher than that of other T4aP and supports T4aP-dependent motility on surfaces of different stiffnesses. Notably, T4aP
Mx
variants with interrupted intersubunit interfaces had decreased bending stiffness, pilus length, and strongly reduced motility. These observations support an evolutionary scenario whereby the large major pilin enables the formation of a rigid T4aP that expands the environmental conditions in which the T4aP system functions.
Divergence-time estimation in Indo-European
Authors: Goldstein David
Published: April 2024

Divergence-time estimation is one of the most important endeavors in historical linguistics. Its importance is
matched only by its difficulty. As Bayesian methods of divergence-time estimation have become more common over the past two
decades, a number of critical issues have come to the fore, including model sensitivity, the dependence of root-age estimates on
uncertain interior-node ages, and the relationship between ancient languages and their modern counterparts. This study addresses
these issues in an investigation of a particularly fraught case within Indo-European: the diversification of Latin into the
Romance languages. The results of this study support a gradualist account of their formation that most likely began after 300
 CE. They also bolster the view that Classical Latin is a sampled ancestor of the Romance languages (i.e., it lies
along the branch leading to the Romance languages).
Polarisation in Venezuelan presidential tweets
Authors: Peterssen Silvia
Published: April 2024

The Venezuelan Presidential Crisis emerged as a unique polarising political scenario in January 2019, when Juan
Guaidó, president of the National Assembly, proclaimed himself interim president of the country, despite the victory obtained by
Nicolás Maduro in the May 2018 presidential elections. Considering this context and the role of social media in the spread of
polarisation, the present manuscript examines how metaphors and social actor representations act as divisive discursive tools in
the tweets of Maduro and Guaidó. To do so, a corpus of tweets posted by these politicians during the first year of the conflict
(2019–2020) is analysed, adopting a target-based approach (Stefanowitsch and Gries
2006) to identify the polarising metaphors and a socio-cognitive framework (Darics and
Koller 2019; van Leeuwen 2008) to study the social actor representations.
The results reveal that these discursive devices help both leaders to construct their social identities, legitimise themselves,
delegitimise the other and reproduce their polarising ideological schemas.
Microwave spin-pumping from an antiferromagnet FeBO3
Authors: Gabrielyan D A , Volkov D A , Kozlova E E , Safin A R , Kalyabin D V , Klimov A A , Preobrazhensky V L , Strugatsky M B , Yagupov S V , Moskal I E , Ovsyannikov G A , Nikitov S A
Published: April 2024

Canted antiferromagnets offer great potential in fundamental research and for use in applications due to their unique properties. The presence of the Dzyaloshinskii–Moriya interaction (DMI) leads to the existence of a weak ferromagnetic moment at room temperature. We study both theoretically and experimentally microwave spin pumping by a quasi-ferromagnetic mode from a canted easy plane antiferromagnet with weak ferromagnetism FeBO3. The conversion of a microwave signal into a constant voltage is realized using the inverse spin Hall effect in an iron borate/heavy metal heterostructure. We use an additional bias magnetic field to selectively tune the resonance frequency of such a microwave detector over a wide range up to 43.5 GHz with a potential sensitivity near 2.5 µV W−1. We confirm the pure spin current nature by changing the polarity of the detected via inverse spin Hall effect voltage by switching the direction of the bias magnetic field. We believe that our results will be useful for the development of highly tunable, portable and sensitive microwave antiferromagnet-based functional devices.
Study on the sensitivity of the Higgs boson couplings in photon–photon collision at CLIC and muon collider
Authors: Spor S
Published: April 2024

In a model-independent way, we explore the potential of photon-induced interactions with the process γ*γ* → ZZ to investigate CP-conserving and CP-violating dimension-six operators of Higgs-gauge boson couplings using the standard model effective field theory. The existence of anomalous H
γ
γ and HZZ couplings is discussed at 3 TeV compact linear collider (CLIC) and 10 TeV muon collider (MuC) with integrated luminosities of 5 and 10 ab−1, respectively. All signal and relevant background events are generated in MadGraph and passed through PYTHIA for parton showering and hadronization. The detector effects are evaluated using CLIC and MuC detector cards tuned in Delphes. We report the 95% confidence level limits on the Wilson coefficients

c

¯

γ

,

c

¯

HB

,

c

¯

HW

,

c

̃

γ

,

c

̃

HB

, and

c

̃

HW

and compare them with the experimental and phenomenological limits.
Optimization of tunnel grouting detection technology based on ultrasonic phased array
Authors: Wang You , Li Guowei , Zhou Lu , Wang Rui
Published: April 2024

Due to the lack of a perfect and convenient method to detect the grouting quality of shield tunnels, an optimized ultrasonic phased array tunnel grouting detection technology is proposed. The particle swarm genetic algorithm is optimized to be used for phased array sparse, and the GA-VMD-SG algorithm is proposed to be used for noise reduction of ultrasonic detection signals, and numerical simulation and experimental methods are used to validate the optimized detection effect of the ultrasonic phased array. The results show that: the GA-PSO algorithm can better simplify the array and reduce the maximum sidelobe value; the GA-VMD-SG algorithm can well reduce the noise of ultrasonic signals; numerical simulation and experiments verify the feasibility of the ultrasonic phased array to detect the quality of grouting and the optimization effect of the two algorithms.
A multi-output fault diagnosis framework for hydraulic system using a CNN-SVM hierarchical learning strategy
Authors: Liang Na , Yuan Zhaohui , Kang Jian , Jiang Ruosong , Zhang Jianrui , Yu Xiaojun
Published: April 2024

Achieving asymptotic and concurrent fault diagnosis in hydraulic system remains a challenging endeavor due to the inherent attributes of the hidden occurrence, simultaneous manifestation, coupling, and limited sample size. To address the above issues, this paper proposes a hierarchical multi-output fault detection and diagnosis framework, namely, HMDF, based on a hierarchical learning strategy to leverage an improved convolutional neural network (CNN) and support vector machine (SVM). Both a multi-channel CNN and a multi-branch CNN are employed to extract and downscale features collected by the sensors at diverse sampling frequencies first, and then, such features are subsequently subjected to classification using SVM. The hierarchical learning strategy enables the identification of different fault states, both at the component and the intra-component level. Additionally, a modified whale optimization algorithm is also utilized to optimize the classification process of SVM. Extensive experiments are conducted to test the proposed HMDF with the hydraulic system datasets. Results show that HMDF achieves a diagnostic accuracy of up to 98.9% for the dataset, surpassing traditional methods reliant on manual extraction of time–frequency features, and it also exhibits superior classification performances with a small sample size. The HMDF is expected to offer a generalized framework for the multi-output fault detection and diagnosis in hydraulic systems and other complex components.
Asymptotically quasiperiodic solutions for time-dependent Hamiltonians
Authors: Scarcella Donato
Published: April 2024

Dynamical systems subject to perturbations that decay over time are relevant in describing many physical models, e.g. when considering the effect of a laser pulse on a molecule, in epidemiological studies, and celestial mechanics. For this purpose, we consider time-dependent Hamiltonian vector fields that are the sum of two components. The first has an invariant torus supporting quasiperiodic solutions, and the second decays as time tends to infinity. The time decay is modelled by functions satisfying suitable conditions verified by a proper polynomial decay in time. We prove the existence of orbits converging as time tends to infinity to the quasiperiodic solutions associated with the unperturbed system. The proof of this result relies on a new strategy based on a refined analysis of the Banach spaces and the functionals involved in the resolution of suitable nonlinear invariant equations. This result is proved for finite differentiable and real-analytic Hamiltonians. Analogous statements for time-dependent vector fields on the torus are also obtained as a corollary. These results extend a previous work of Canadell and de la Llave, where only exponential decay in time is considered. The relaxation of the decay in time makes the results in the present paper suited for applications in many physical problems, such as celestial dynamics.
Sensitivity volume as figure-of-merit for maximizing data importance in electrical impedance tomography
Authors: Onsager Claire C , Wang Chulin , Costakis Charles , Aygen Can C , Lang Lauren , van der Lee Suzan , Grayson Matthew A
Published: April 2024

Objective. Electrical impedance tomography (EIT) is a noninvasive imaging method whereby electrical measurements on the periphery of a heterogeneous conductor are inverted to map its internal conductivity. The EIT method proposed here aims to improve computational speed and noise tolerance by introducing sensitivity volume as a figure-of-merit for comparing EIT measurement protocols. Approach. Each measurement is shown to correspond to a sensitivity vector in model space, such that the set of measurements, in turn, corresponds to a set of vectors that subtend a sensitivity volume in model space. A maximal sensitivity volume identifies the measurement protocol with the greatest sensitivity and greatest mutual orthogonality. A distinguishability criterion is generalized to quantify the increased noise tolerance of high sensitivity measurements. Main result. The sensitivity volume method allows the model space dimension to be minimized to match that of the data space, and the data importance to be increased within an expanded space of measurements defined by an increased number of contacts. Significance. The reduction in model space dimension is shown to increase computational efficiency, accelerating tomographic inversion by several orders of magnitude, while the enhanced sensitivity tolerates higher noise levels up to several orders of magnitude larger than standard methods.
Electrical and mechanical limits of ex situ MgB2 wires for cabling
Authors: Kováč P , Búran M , Kováč J , Melišek T , Hušek I , Berek D , Mauceri P , Spina T , Bruzek Ch-E
Published: April 2024

One of the objectives of the SCARLET project is to develop and industrially manufacture superconducting MgB2 cables cooled by liquid hydrogen. The ex situ powder-in-tube MgB2 wires manufactured by ASG are considered for the cable design that can carry DC current of 20 kA. These braided superconducting wires, containing brittle filaments, require high current. Thus, the study of the electro-mechanical properties of MgB2 wires is crucial for the cable design and its functional use. Superconducting wires have to withstand all the stresses applied during the cabling process, installation, and operations at the temperature of around 20 K. Hence, several configurations of MgB2/Ni/Monel composite wires have been subjected to detailed electrical and mechanical characterizations, which allow the estimation of the stress limits during the manufacturing of the designed cable. These experiments demonstrated that the maximal tensile stress applied to the wire at room temperature should be below 180–200 MPa, and safety bending observed for the outer filament strains was below 0.3%–0.35%. It is also revealed that the limit of acceptable torsion (expressed by the twist pitch to wire diameter L
t/d
w) is affected by the filament architecture and wire diameter. This limit should be above 100 for 1 mm wire and above 150 for 1.53 mm wire.
Quantum G-coherence factorization law under fully and strictly incoherent operations
Authors: Zhao Xinzhi , Shao Jianwei , Zheng Yi , Zhang Wen-Zhao , Zhang Chengjie
Published: April 2024

Quantum coherence plays an important role in quantum resource theory, which is strongly related with entanglement. In order to quantify the full coherence of qudit states, we define G-coherence and convex roof of G-coherence, and prove that the G-coherence is a strong coherence monotone and the convex roof of G-coherence is a coherence measure under fully and strictly incoherent operation (FSIO), respectively. Similar to the entanglement factorization law, we prove a coherence factorization law for arbitraryd-dimensional quantum pure and mixed states under FSIO channels, which generalizes the entanglement factorization law for bipartite pure states. Our results will play an important role in the simplification of dynamical coherence measure.
Verifiable blind quantum computation over collective-noise
Authors: Luo Yuan-Mao , Yang Zhen , Wu Guang-Yang , Yan Yu-Zhan , Bai Ming-Qiang
Published: April 2024

Blind quantum computation(BQC) is a new type of secure quantum computation. In the natural environment, the qubits used in BQC will inevitably be affected by the noise, and the client cannot guarantee the correctness of computational results when the server is dishonest. This paper proposes a verifiable BQC over collective-noise based on quantum error correction to solve these two problems. Furthermore, the proposed protocol needs to expand Alice’s quantum capabilities. The client makes single-qubit measurements on the qubits, encoded and transmitted by the server. As a result, they protect qubits used to compute and utilize single-qubits to verify.
First-principles study of structural and electronic properties of multiferroic oxide Mn3TeO6 under high pressure
Authors: Pan 潘 Xiao-Long 小龙 , Wang 王 Hao 豪 , Liu 柳 Lei 雷 , Chen 陈 Xiang-Rong 向荣 , Geng 耿 Hua-Yun 华运
Published: April 2024

Mn3TeO6 (MTO) has been experimentally found to adopt a P21/n structure under high pressure, which exhibits a significantly smaller band gap compared to the atmospheric

R

3
¯

phase. In this study, we systematically investigate the magnetism, structural phase transition, and electronic properties of MTO under high pressure through first-principles calculations. Both

R

3
¯

and P21/n phases of MTO are antiferromagnetic at zero temperature. The

R

3
¯

phase transforms to the P21/n phase at 7.58 GPa, accompanied by a considerable volume collapse of about 6.47%. Employing the accurate method that combines DFT+U and GW, the calculated band gap of

R

3
¯

phase at zero pressure is very close to the experimental values, while that of the P21/n phase is significantly overestimated. The main reason for this difference is that the experimental study incorrectly used the Kubelka–Munk plot for the indirect band gap to obtain the band gap of the P21/n phase instead of the Kubelka–Munk plot for the direct band gap. Furthermore, our study reveals that the transition from the

R

3
¯

phase to the P21/n phase is accompanied by a slight reduction in the band gap.
A color image encryption scheme based on a 2D coupled chaotic system and diagonal scrambling algorithm
Authors: Su 苏 Jingming 静明 , Fang 方 Shihui 士辉 , Hong 洪 Yan 炎 , Wen 温 Yan 言
Published: April 2024

A novel color image encryption scheme is developed to enhance the security of encryption without increasing the complexity. Firstly, the plain color image is decomposed into three grayscale plain images, which are converted into the frequency domain coefficient matrices (FDCM) with discrete cosine transform (DCT) operation. After that, a two-dimensional (2D) coupled chaotic system is developed and used to generate one group of embedded matrices and another group of encryption matrices, respectively. The embedded matrices are integrated with the FDCM to fulfill the frequency domain encryption, and then the inverse DCT processing is implemented to recover the spatial domain signal. Eventually, under the function of the encryption matrices and the proposed diagonal scrambling algorithm, the final color ciphertext is obtained. The experimental results show that the proposed method can not only ensure efficient encryption but also satisfy various sizes of image encryption. Besides, it has better performance than other similar techniques in statistical feature analysis, such as key space, key sensitivity, anti-differential attack, information entropy, noise attack, etc.
Corrigendum to “Absolute partial and total ionization cross sections of carbon monoxide with electron collision from 350 eV to 8000 eV”
Authors: Khan Taj Wali , Huang 黄 Weizhe 伟哲 , Wang 王 Enliang 恩亮 , Shan 单 Xu 旭 , Chen 陈 Xiangjun 向军
Published: April 2024

The numbers of longitudinal axis in Fig. 1(a) of the paper [Chin. Phys. B
33 043401 (2024)] have been corrected. This modification does not affect the result presented in the paper.
Universal test system for boards hosting bPOL12V DC-DC converters
Authors: Stachon K. , Dissertori G. , Gadek T. , Lustermann W. ,   the CMS collaboration
Published: April 2024

The ECAL Barrel and MTD Barrel Timing Layer subdetectors of CMS are approaching series production of electronic boards, including voltage conditioning PCBs: LVRs and PCCs respectively. 2448 LVRs and 864 PCCs will be installed during LS3 of the LHC. These boards are hosting radiation-tolerant bPOL12V ASICs which convert a broad input voltage range into required voltage levels for microelectronics between 1.2–2.5 V. Each card must be tested multiple times at various production stages to ensure its conformity. This contribution describes a methodology of testing bPOL12V conversion quality including the detection of instability regions at certain load levels.
NAPA-p1: monolithic nanosecond timing pixel for large area sensors, designed for future e
+
e
- colliders
Authors: Habib A. , Bakalis C. , Brau J.E. , Breidenbach M. , Rota L. , Vernieri C. , Dragone A.
Published: April 2024

NAPA-p1 is a prototype Monolithic Active Pixel Sensor 'MAPS' developed as a first iteration towards meeting the detectors general requirements for future e
+
e
- colliders. Long-term objective is to develop a wafer-scale sensor in MAPS with an area ∼ 10 cm × 10 cm. This article presents the motivations for the design choices of NAPA-p1, translating the physics requirement into circuit specifications. Simulations show a pixel jitter of < 400 ps-rms and an equivalent noise charge of 13 e
-rms with an average power consumption of 1.15 mW/cm2 assuming a 1% duty cycle, meeting the target specifications. The prototype is designed in 65 nm CMOS imaging technology, with dimensions of 1.5 mm × 1.5 mm and a pixel pitch of 25 μm. The prototype chip has been fabricated and characterization results will be available soon.
Two HVCMOS active pixel ASIC designs for the Measurement of GCR and SEP with a combined dynamic range of >80 dB
Authors: Papadomanolaki E. , Papangelis A. , Torris M. , Theodoratos G. , Glikiotis I. , Lambropoulos C.
Published: April 2024

The design of HVCMOS detectors for measuring Galactic Cosmic Rays (GCR) and Solar Energetic Particles (SEP) is presented, with the goal of covering a very wide dynamic range (from ∼0.5 fC to pC). Two different pixel designs are shown, one with low gain tailored to high energy depositions and one with high gain for low energy depositions. Both designs utilize a sensing diode consisting of a fully-depleted, high resistivity substrate and a segmented deep n-well on top. LFoundry 0.15 μm technology is used. The design choices are backed by simulation results and preliminary measurements.
The effects of keratin-coated titanium on osteoblast function and bone regeneration
Authors: Ranjit Eliza , Hamlet Stephen , Shelper Todd , Sharma Ajay , Love Robert
Published: April 2024

Wool derived keratin, due to its demonstrated ability to promote bone formation, has been suggested as a potential bioactive material for implant surfaces. The aim of this study was to assess the effects of keratin-coated titanium on osteoblast function in vitro and bone healing in vivo. Keratin-coated titanium surfaces were fabricated via solvent casting and molecular grafting. The effect of these surfaces on the attachment, osteogenic gene, and osteogenic protein expression of MG-63 osteoblast-like cells were quantified in vitro. The effect of these keratin-modified surfaces on bone healing over three weeks using an intraosseous calvaria defect was assessed in rodents. Keratin coating did not affect MG-63 proliferation or viability, but enhanced osteopontin, osteocalcin and bone morphogenetic expression in vitro. Histological analysis of recovered calvaria specimens showed osseous defects covered with keratin-coated titanium had a higher percentage of new bone area two weeks after implantation compared to that in defects covered with titanium alone. The keratin-coated surfaces were biocompatible and stimulated osteogenic expression in adherent MG-63 osteoblasts. Furthermore, a pilot preclinical study in rodents suggested keratin may stimulate earlier intraosseous calvaria bone healing.
3D printing of an artificial intelligence-generated patient-specific coronary artery segmentation in a support bath
Authors: Sokmen Serkan , Cakmak Soner , Oksuz Ilkay
Published: April 2024

Accurate segmentation of coronary artery tree and personalized 3D printing from medical images is essential for CAD diagnosis and treatment. The current literature on 3D printing relies solely on generic models created with different software or 3D coronary artery models manually segmented from medical images. Moreover, there are not many studies examining the bioprintability of a 3D model generated by artificial intelligence (AI) segmentation for complex and branched structures. In this study, deep learning algorithms with transfer learning have been employed for accurate segmentation of the coronary artery tree from medical images to generate printable segmentations. We propose a combination of deep learning and 3D printing, which accurately segments and prints complex vascular patterns in coronary arteries. Then, we performed the 3D printing of the AI-generated coronary artery segmentation for the fabrication of bifurcated hollow vascular structure. Our results indicate improved performance of segmentation with the aid of transfer learning with a Dice overlap score of 0.86 on a test set of 10 coronary tomography angiography images. Then, bifurcated regions from 3D models were printed into the Pluronic F-127 support bath using alginate + glucomannan hydrogel. We successfully fabricated the bifurcated coronary artery structures with high length and wall thickness accuracy, however, the outer diameters of the vessels and length of the bifurcation point differ from the 3D models. The extrusion of unnecessary material, primarily observed when the nozzle moves from left to the right vessel during 3D printing, can be mitigated by adjusting the nozzle speed. Moreover, the shape accuracy can also be improved by designing a multi-axis printhead that can change the printing angle in three dimensions. Thus, this study demonstrates the potential of the use of AI-segmented 3D models in the 3D printing of coronary artery structures and, when further improved, can be used for the fabrication of patient-specific vascular implants.