bluuebunny/crossref_metadata_2025_split huggingface dataset:
Discrete fiber skeleton strengthened magnetorheological grease and a novel H–B model based on fiber parameters
Authors: Wang Yingjian , Wang Meng , Gao Peixin , Yu Tao , Xi Jun 
Published: March 2024

Magnetorheological fluid (MRF) porous fabric composite has been demonstrated to improve the shear properties of MRF. Non-woven fabric is manufactured from a multitude of fibers through spinning or melt-blown processing methods. As the fundamental unit of non-woven fabric, fibers without spinning or melt-blown directly influence the shear properties of magnetorheological (MR) materials. However, the effect of unprocessed fiber on the shear properties of MR grease remains uncertain. This study introduces a novel MR grease with fiber threads (MRG-FT) by incorporating fiber threads into MRG. The effects of fiber thread length, mass fraction, and material type on MRG shear stress are investigated. Compared to conventional MRG, the maximum shear stress of MRG-FT is increased by 31.8% under the magnetic field of 0.64 T. A novel Herschel–Bulkley–Fiber (H-B-F) model that considers fiber parameters (tenacity, mass fraction, etc.) is proposed based on the H–B model. To validate the enhancement of MRG by fiber threads, a linear damper based on shear mode has been designed and tested. The results demonstrate a 23.8% increase in the maximum damping force of MRG-FT compared to conventional MRG under an excitation current of 1.6 A. This study reveals the influence of fiber threads, which directly influences the shear properties of MRG upon the application of the magnetic field. The maximum damping force of the MRG can be increased by 23.8% by only 1.5% mass fraction of fibers.
Experimental upper bounds for resonance-enhanced entangled two-photon absorption cross section of indocyanine green
Authors: He Manni , Hickam Bryce P. , Harper Nathan , Cushing Scott K. 
Published: March 2024

Resonant intermediate states have been proposed to increase the efficiency of entangled two-photon absorption (ETPA). Although resonance-enhanced ETPA (r-ETPA) has been demonstrated in atomic systems using bright squeezed vacuum, it has not been studied in organic molecules. We investigate for the first time r-ETPA in an organic molecular dye, indocyanine green (ICG), when excited by broadband entangled photons in near-IR. Similar to many reported virtual state mediated ETPA (v-ETPA) measurements, no r-ETPA signals are measured, with an experimental upper bound for the cross section placed at 6(±2) × 10−23 cm2. In addition, the classical resonance-enhanced two-photon absorption (r-TPA) cross section of ICG at 800 nm is measured for the first time to be 20(±13) GM, where 1 GM equals 10−50 cm4 s, suggesting that having a resonant intermediate state does not significantly enhance two-photon processes in ICG. The spectrotemporally resolved emission signatures of ICG excited by entangled photons are also presented to support this conclusion.
Analysis of active screen low temperature plasma-assisted deposition of iron nitride thin films on silicon (100) substrate
Authors: Asghar Muhammad , Bashir Muhammad Imran , Tayyab Muhammad , Shafiq Muhammad , Naz Muhammad Yasin , Ibrahim Ahmed Ahmed , Shoaib Muhammad 
Published: March 2024

Thin film technology has gained significant attention in the industry due to its superior properties in comparison to bulk materials. Specifically, iron nitride-based thin films are a fascinating area of research in semiconductor technologies. The crystal structure and optical properties of these films are highly dependent on the growth method, deposition technique, gas flow, pressure, and several other factors. In this work, we prepared polycrystalline thin films of iron nitride on silicon (100) substrates by using the active screen low temperature plasma-assisted method. These films are deposited under the varying atmosphere of nitrogen and hydrogen in four proportions: 80% N2 + 15% H2; 60% N2 + 35% H2; 40% N2 + 55% H2; and 20% N2 + 75% H2, along with 5% argon to investigate its influence on the structural, morphological, and optical properties. The structural properties are determined by x-ray diffraction and revealed a mixture of ζ-Fe2N, ε-Fe3N, and γ′-Fe4N phases. Surface morphology is analyzed by scanning electron microscopy, which confirms the formation of a thin layer on the substrate. In addition, UV–Vis spectrophotometry is used to assess the optical response and bandgap energy of the samples. The result of UV–Vis optical diffuse reflectance spectra shows a decrease in the bandgap from 3.17 to 3.06 eV of substrate. For the S4 sample, we obtained a pure Fe4N phase, showing a significant decrease in the energy bandgap.
First-principles study of high-pressure structural phase transition and superconductivity of YBeH8
Authors: Du Jianhui , Jiang Qiwen , Zhang Zihan , Zhao Wendi , Chen Ling , Huo ZiHao , Song Hao , Tian Fubo , Duan Defang , Cui Tian 
Published: March 2024

The theory-led prediction of LaBeH8, which has a high superconducting critical temperature (Tc) above liquid nitrogen under a pressure level below 1 Mbar, has been experimentally confirmed. YBeH8, which has a structural configuration similar to that of LaBeH8, has also been predicted to be a high-temperature superconductor at high pressure. In this study, we focus on the structural phase transition and superconductivity of YBeH8 under pressure by using first-principles calculations. Except for the known face-centered cubic phase of Fm3̄m, we found a monoclinic phase with P1̄ symmetry. Moreover, the P1̄ phase transforms to the Fm3̄m phase at ∼200 GPa with zero-point energy corrections. Interestingly, the P1̄ phase undergoes a complex electronic phase transition from semiconductor to metal and then to superconducting states with a low Tc of 40 K at 200 GPa. The Fm3̄m phase exhibits a high Tc of 201 K at 200 GPa, and its Tc does not change significantly with pressure. When we combine the method using two coupling constants, λopt and λac, with first-principles calculations, λopt is mainly supplied by the Be–H alloy backbone, which accounts for about 85% of total λ and makes the greatest contribution to the high Tc. These insights not only contribute to a deeper understanding of the superconducting behavior of this ternary hydride but may also guide the experimental synthesis of hydrogen-rich compounds.
An approximate application of quantum gravity to the rotation problem
Authors: Jones R Michael 
Published: March 2024

Abstract
Arbitrary initial conditions allow solutions of Einstein’s field equations for General Relativity to have arbitrarily large relative rotation of matter and inertial frames. The ‘Rotation Problem’ is to explain why the measured relative rotation rate is so small. As it turns out, nearly any reasonable theory of quantum gravity can solve the rotation problem by phase interference. Even as early as about a quarter of a second after the initial simgularity, quantum cosmology would limit the cosmologies that contribute significantly to a path integral calculation to have relative rms rotation rates less than about 10−51 radians per year. Those calculations are based on using 50 e-foldings during inflation. For 55 or 60 e-foldings, the cosmologies contributing significantly to the path integral would have even smaller relative rotation rates. In addition, although inflation dominates the calculation, even if there had been no inflation, the cosmologies contributing significantly to the path integral would have relative rotation rates less than about 10−32 radians per year at about a quarter of a second after the initial singularity. These calculations are insensitive to the details of the theory of quantum gravity because the main factor depends only on the size of the visible Universe, the Planck time, the free-space speed of light, the Hubble parameter, and the number of e-foldings during inflation. These calculations use the Einstein–Hilbert action in quantum gravity, including large-scale relative rotation of inertial frames and the matter distribution, in which each ‘path’ is a cosmology with a different rms relative rotation rate. The calculations include inflation for 50, 55, and 60 e-foldings, and for values of the dependence of relative rotation rate on cosmological scale factor a as a
−m
for various values of m. The calculation shows that the action is an extremum at zero rms relative rotation rate.
Uniqueness results for inverse source problems for semilinear elliptic equations
Authors: Liimatainen Tony , Lin Yi-Hsuan 
Published: March 2024

Abstract
We study inverse source problems associated to semilinear elliptic equations of the form

Δ
u

x

+
a

x
,
u

=
F

x

on a bounded domain

Ω
⊂

R

n

,

n
⩾
2

. We show that it is possible to use nonlinearity to recover both the source F and the nonlinearity

a
(
x
,
u
)

simultaneously and uniquely for a class of nonlinearities. This is in contrast to inverse source problems for linear equations, which always have a natural (gauge) symmetry that obstructs the unique recovery of the source. The class of nonlinearities for which we can uniquely recover the source and nonlinearity, includes a class of polynomials, which we characterize, and exponential nonlinearities.
For general nonlinearities

a
(
x
,
u
)

, we recover the source F(x) and the Taylor coefficients

∂
u
k

a
(
x
,
u
)

up to a gauge symmetry. We recover general polynomial nonlinearities up to the gauge symmetry. Our results also generalize results of Feizmohammadi and Oksanen (2020 J. Differ. Equ.
269 4683–719), Lassas et al (2020 Rev. Mat. Iberoam.
37 1553–80) by removing the assumption that

u
≡
0

is a solution. To prove our results, we consider linearizations around possibly large solutions.
Our results can lead to new practical applications, because we show that many practical models do not have the obstruction for unique recovery that has restricted the applicability of inverse source problems for linear models.
Consistency of the Bayes method for the inverse scattering problem
Authors: Furuya Takashi , Kow Pu-Zhao , Wang Jenn-Nan 
Published: March 2024

AbstractIn this work, we consider the inverse scattering problem of determining an unknown refractive index from the far-field measurements using the nonparametric Bayesian approach. We use a collection of large ‘samples’, which are noisy discrete measurements taking from the scattering amplitude. We will study the frequentist property of the posterior distribution as the sample size tends to infinity. Our aim is to establish the consistency of the posterior distribution with an explicit contraction rate in terms of the sample size. We will consider two different priors on the space of parameters. The proof relies on the stability estimates of the forward and inverse problems. Due to the ill-posedness of the inverse scattering problem, the contraction rate is of a logarithmic type. We also show that such contraction rate is optimal in the statistical minimax sense.
Installation angle calibration between the star sensor and gyro unit using the equivalent rotation vector transformation
Authors: Ma Liheng , Li Qiyao , Chen Yanfeng , Luo Xiao , Kai Li , Zhang Su 
Published: March 2024

Abstract
To improve the dynamic performance of the star sensor, different star image frames are correlated using the attitude-correlated frame (ACF) approach, and the attitude changes among these star image frames are measured by the strapdown gyro unit (GU). The GU consists of three orthogonally assembled gyros, while the accelerometer is excluded. Accurate calibration of the installation angles between the star sensor and the GU is essential for the ACF approach. An installation angle calibration method using the equivalent rotation vector transformation between the star sensor and the GU is proposed in this work. Through three to five maneuverings of the star sensor/GU system, the equivalent rotation vector transformation of the observed vector is performed by the installation matrix, and the optimal values of the installation angles are estimated. Simulations and experiments are designed and conducted, and both verify the proposed calibration method. The calibration results in the experiment show that the standard deviation of the installation angles in each measurement data group is less than 5 arcseconds and the difference between different data sets is less than 14 arcseconds, both for the three axes, which are accurate enough for the ACF approach and other applications.
Rolling bearing fault diagnosis based on the fusion of sparse filtering and discriminative domain adaptation method under multi-channel data-driven
Authors: Jiao Zonghao , Zhang Zhongwei , Li Youjia , Wu Yuting , Liu Lu , Shao Sujuan 
Published: March 2024

Abstract
Currently, the diagnostic performance of many deep learning algorithms may drop dramatically when the distribution of training data is significantly different from that of the test data. Moreover, the fault diagnosis approaches based on single-channel data may suffer problems such as large precision fluctuation, low reliability, and incomplete expression of fault features. To overcome the above deficiencies, a novel multi-channel data-driven fault recognition method based on the fusion of sparse filtering (SF) and discriminative domain adaptation (MSFDDA) is proposed in this article. Firstly, inspired by attention mechanisms and information fusion methods, a spectrum-based weighted multi-channel data fusion strategy is designed to fully utilize the data collected by sensors to obtain a more comprehensive representation of fault features. Then, the joint probability-based discriminative maximum mean discrepancy algorithm is introduced into the SF method to strengthen the capability of extracting the domain invariant features. Finally, two bearing datasets are employed to verify the validity of the MSFDDA method, which proved to be superior to other current domain adaptation methods.
Statistical analysis of magnetic divertor configuration influence on H-mode transitions
Authors: Andrew Y , Dunsmore J , Ashton-Key T , Farre Kaga H , Kim E , Rhodes T L , Schmitz L , Yan Z 
Published: March 2024

Abstract
DIII-D plasmas are compared for two upper divertor configurations: with the outer strike point on the small angle slot (SAS) divertor target and with the outer strike point on the horizontal divertor target (HT). Scanning the vertical distance between the magnetic null point and the divertor target over a range 0.10–0.16 m is shown to increase the threshold power,

P

th

, and edge plasma power,

P

Loss

, for the low-to-high confinement (L–H) and H–L transitions respectively, by up to a factor of 1.4. The X-point height scans were performed at three L-mode core plasma line average electron densities,

n
¯

e

=

1.2, 2.2 and 3.6

×

10

19

m

−
3

, to investigate the density dependence of divertor magnetic configuration influence on

P

th

. The X-point height,

Z
x-pt

, was further extended across the range 0.16–0.22 m with the more open HT divertor configuration, for which a clear decrease in

P

th

with increasing

Z
x-pt

is observed. The dependence of

P
th

on divertor magnetic geometry is further investigated using a time-dependent probability density function (PDF) model and information geometry to elucidate the roles played by pedestal plasma turbulence and perpendicular velocity flows. The degree of stochasticity of the plasma turbulence is observed to be sensitive to the plasma heating rate. The calculated square of the information rate shows changes in the relative density fluctuations and perpendicular velocity PDFs begin 2–5 ms prior to the L–H transition for three plasmas; providing a crucial measurement of the dynamic timescale of external transport barrier formation. Additionally, both information length and rate provide potential predictors of the L–H transition for these plasmas.
Variational learning algorithms for quantum query complexity
Authors: Wu Zipeng , Hou Shi-Yao , Zhang Chao , Li Lvzhou , Zeng Bei 
Published: March 2024

Abstract
Quantum query complexity is pivotal in the analysis of quantum algorithms, encompassing well-known examples like search and period-finding algorithms. These algorithms typically involve a sequence of unitary operations and oracle calls dependent on an input variable. In this study, we introduce a variational learning approach to explore quantum query complexity. Our method employs an efficient parameterization of the unitary operations and utilizes a loss function derived from the algorithm’s error probability. We apply this technique to various quantum query complexities, notably devising a new algorithm that resolves the 5-bit Hamming modulo problem with four queries, addressing an open question from Cornelissen et al (2021 arXiv:2112.14682). This finding is corroborated by a semidefinite programming (SDP) approach. Our numerical method exhibits superior memory efficiency compared to SDP and can identify quantum query algorithms (QQAs) that require a smaller workspace register dimension, an aspect not optimized by SDP. These advancements present a significant step forward in the practical application and understanding of QQAs.
A noise-robust quantum dynamics learning protocol based on Choi–Jamiolkowski isomorphism: theory and experiment
Authors: Chen Xin-Yu , Gao Pan , Qiu Chu-Dan , Lu Ya-Nan , Yang Fan , Zhao Yuanyuan , Li Hang , Zhang Jiang , Wei Shijie , Xing Tonghao , Pan Xin-Yu , Ruan Dong , Zhang Feihao , Li Keren , Long Guilu 
Published: March 2024

Abstract
With the rapid development of quantum technology, the growing manipulated Hilbert space makes learning the dynamics of the quantum system a significant challenge. Machine learning technique has brought apparent advantages in some learning strategies, therefore, we introduce it to indirect learning in this paper. Based on Choi–Jamiolkowski isomorphism, we propose a protocol that learns the dynamics of an inaccessible quantum system using a quantum device at hand. For an n-qubit system, the learning task can be done iteratively, with operational complexity

O

(
poly
(
n
,
L
)

/

ϵ
2

)

in each iteration, where L is the circuit depth and ε is the measurement error. Then we theoretically prove its noise resilience to global depolarization, state preparation and measurement noise, and unitary noise in gates implementation, where we find the learned dynamics stay invariant. Finally, we investigate the protocol experimentally on a nitrogen-vacancy center system with a natural noise source. The results show that the behavior of a relatively intractable nuclear spin can be learned through an easily accessible electron spin under different noise models, demonstrating the protocol’s feasibility.
Effects of Al and V on deformation behavior and microscopic mechanism of titanium alloy at ultra-low temperature using molecular dynamics
Authors: Zhang Long , Liu Gaoyang , Li Jiayi , He Dong 
Published: March 2024

Abstract
A uniaxial tensile was executed with the molecular dynamics method, while the interaction between Ti, Al and V was described by hybrid potential. The influences of Al and V elements on the plastic deformation behavior and microscopic deformation mechanism of Ti-Al-V alloy were studied under ultra-low temperatures. The results show that the high content of Al and V elements leads to a sudden decrease of plasticity at 300 K. The plasticity is slightly reduced with increasing Al content when the content of V is 3.3~6.2 wt.% at 77 K. However, with the temperature reduced to 50 K, Al promotes the activation of dislocation when the content of V is high (6.2 wt.%) and hinders the activation of dislocation when V content is low (0.4 wt.%). At high V content (6.2 wt.%), the increase in plasticity with increasing Al content is more pronounced. Therefore, the strength and plasticity of Ti6.5Al6.2V increase with decreasing temperature.
A new strategy for insulators to improve the ability of semiconductors to reduce Cr (VI)
Authors: Ye Junchen , Wang Dianhui , Zhong Yan , Liu Hao , Wang Wenyi , Wei Nini 
Published: March 2024

Abstract
Insulators have always been a kind of material that has not been valued in the field of catalysis. In order to expand its application in the field of photocatalytic treatment of heavy metal ions, a series of CdS/SrCO3 catalysts are prepared. XRD proves the successful synthesis of the composite catalyst, and TEM reveals the tight connection between CdS and SrCO3. Transient photocurrent and electrochemical impedance spectroscopy show that the composite catalyst has a better electron-hole pair separation effect and electron transport rate than the two single-phase materials. The catalyst has excellent photocatalytic properties and good stability. Finally, the reaction kinetics in the process of photocatalytic reduction of composite catalyst is discussed.
Front-End Board for large area SiPM detector
Authors: Venettacci C. , Fabbri A. , Petrucci F. , Mari S.M. ,   the JUNO collaboration
Published: March 2024

Abstract
Silicon PhotoMultipliers (SiPMs) are widely employed for several applications, such as High Energy Physics experiments, as well as other research and industrial fields. SiPMs operating at low temperature, in particular, are the most interesting application for the new large particle detectors for neutrinos and dark matter experiments. In this work we present a low-noise, high-speed front-end electronics (Front-End Boards, FEBs) for large area SiPMs to be employed in the JUNO-TAO experiment for rare event searching. The FEBs are able to manage the signals coming from a 25 cm2 SiPM tile, showing single photoelectron resolution better than 13% and dynamic range up to 250 photoelectrons. A careful approach to the front-end electronics design has shown to be critical in order to fully keep the exceptional performances of the SiPMs in terms of single photon detection, dynamic range, and fast timing properties. The sub-nanosecond timing properties make them suitable to work with the typical mixtures of liquid scintillators currently being used in particle and astroparticle physics experiments. The JUNO-TAO detector will achieve an energy resolution better than 2% at 1 MeV by the use of state-of-the-art SiPMs operating at -50°C. A dedicated readout system has been developed in order to collect and digitize the ∼8,000 channels needed to ensure the requested performances. A complete test report about the performance of the pre-production FEBs batch will be presented, showing the solution taken to ensure a high stability and reproducibility of the results.
Design and implementation of neural network based conditions for the CMS Level-1 Global Trigger upgrade for the HL-LHC
Authors: Bortolato G. , Cepeda M. , Heikkilä J. , Huber B. , Leutgeb E. , Rabady D. , Sakulin H. ,   the CMS collaboration
Published: March 2024

Abstract
The CMS detector will be upgraded to maintain, or even improve, the physics acceptance under the harsh data taking conditions foreseen during the High-Luminosity LHC operations. In particular, the trigger system (Level-1 and High Level Triggers) will be completely redesigned to utilize detailed information from sub-detectors at the bunch crossing rate: the upgraded Global Trigger will use high-precision trigger objects to provide the Level-1 decision. Besides cut-based algorithms, novel machine-learning-based algorithms will also be included in the Global Trigger to achieve a higher selection efficiency and detect unexpected signals. Implementation of these novel algorithms is presented, focusing on how the neural network models can be optimized to ensure a feasible hardware implementation. The performance and resource usage of the optimized neural network models are discussed in detail.