bluuebunny/crossref_metadata_2025 huggingface dataset:
Testamentary manumission and emotional bonds in eighteenth-century Saint-Domingue
Authors: Palmer Jennifer L.
Published: November 2024

Plantation slavery brought whites and people of color into constant intimate contact in a system
of intense forcible domination and subordination. This generated powerful emotions on the part of both enslavers and
the enslaved. A close reading of one testament from eighteenth-century French Saint-Domingue suggests that systems of
enslavement prompted a range of emotions on the part of white slave owners. While the emotional responses of the
enslaved are much more difficult to identify, this example suggests that emotions played a key role in leading to or
discouraging manumission. Why else would the wealthy, childless widow Marie-Magdeleine Rossignol manumit nine enslaved
people in her will?
Lectures on language theory 1942–1943
Authors: Hjelmslev Louis
Published: November 2024

The present book is the English translation of Louis Hjelmslev’s lectures on glossematics, the theory of language developed in the forties by him and Hans Jørgen Uldall, and taught at the University of Copenhagen in 1942-43, thoroughly taken down in shorthand by his student Harry Wett Frederiksen. The document, unpublished so far, is one-of-a-kind in its pedagogical dimension, as it aims to introduce students, and now readers, to the glossematician’s workshop, informally discussing its theoretical framework, the operations employed in description and the reasons why such operations were devised via a concrete analysis of Hans Christian Andersen’s fairy-tale “The Sweethearts”. Overall, the document offers a unique glimpse into the machinery of one of the most epistemologically aware and rigorous theories of language developed in the 20th century.
High precision measurement of shear modulus based on Michelson equal thickness interference
Authors: Chen Tairan , Zheng Yang , Hong Ruiyang , Fu Pang , Liao Peng , Jia Xinyan , Fan Daihe
Published: November 2024

A high-precision measurement device for shear modulus was designed by combining the ideas of the torsion balance and the principle of Michelson equal thickness interference. Detailed measurement methods were provided, making this device suitable for use in university physics experimental courses. Utilizing the newly developed experimental setup, a practical measurement of the shear modulus of 6061-aluminum alloy rectangular cross-section rod sample was performed, yielding a result of

G
exp

=
26.0
±
1.7

GPa

at a level of confidence of 68%. The relative error in comparison to the theoretical value G
theo = 25.9 GPa was only η = 0.39%. The process and method outlined in this paper can enhance undergraduate students’ practical skills in creating new experimental measurement devices using the techniques they have learned. It also offers a novel approach for conducting high-precision measurements of shear modulus in laboratory. Additionally, the device incorporates a wealth of physical concepts and content, thereby enriching the material covered in college physics experiment courses.
Direct prediction of saturated neoclassical tearing modes in slab using an equilibrium approach
Authors: Balkovic E , Loizu J , Graves J P , Huang Y-M , Smiet C
Published: November 2024

We demonstrate for the first time that the nonlinear saturation of neoclassical tearing modes (NTMs) can be found directly using a variational principle based on Taylor relaxation, without needing to simulate the intermediate, resistivity-dependent dynamics. As in previous investigations of classical tearing mode saturation (Loizu et al 2020 Phys. Plasmas
27 070701; Loizu and Bonfiglio 2023 J. Plasma Phys.
89 905890507), we make use of Stepped Pressure Equilibrium Code (SPEC) (Hudson et al 2012 Phys. Plasmas
19 112502), an equilibrium solver based on the variational principle of the multi-region relaxed magnetohydrodynamics (MHDs), featuring stepped pressure profiles and arbitrary magnetic topology. We work in slab geometry and employ a simple bootstrap current model

J

bs

=
C

∇
p

to study the bootstrap-driven tearing modes, scanning over the asymptotic matching parameter

Δ

′

and bootstrap current strength. Saturated island widths produced by SPEC agree well with the predictions of an initial value resistive MHDs code (Huang and Bhattacharjee 2016 Astrophys. J.
818 20) while being orders of magnitude faster to calculate. Additionally, we observe good agreement with a simple analytical modified Rutherford equation, without requiring any fitting coefficients. The match is obtained for both linearly unstable classical tearing modes in the presence of bootstrap current, and NTMs, which are linearly stable but nonlinear-unstable due to the effects of the bootstrap current.
Negative stiffness mechanical metamaterials: a review
Authors: Tan Xiaojun , Cao Bo , Liu Xin , Zhu Shaowei , Chen Shuai , Kadic Muamer , Wang Bing
Published: November 2024

Metamaterials have thrived in recent years, with negative stiffness mechanical metamaterials (NSMMS) emerging as an essential branch. Extensive research in the past decade has yielded fruitful results in this field. This work encompasses an in-depth exploration of the origin of negative stiffness behavior, along with detailed demonstrations of the implementation mechanism and construction methods used in NSMMS. Furthermore, the paper highlights the diverse range of applications for these metamaterials, including energy absorption, advanced actuators, deployable and morphing structures, vibration control, and more. Lastly, a brief glimpse into the future development direction of this metamaterial is proposed.
Magnetoelectric effects in a heterostructure of magnetostrictive fiber composite and piezopolymer film
Authors: Savelev D V , Musatov V I , Fedulov F A , Fetisov L Y , Burdin D A , Alekhina Y A , Chashin D V , Shakhurin E S , Fetisov Y K
Published: November 2024

Magnetoelectric (ME) effects in composite heterostructures comprising ferromagnetic (FM) and piezoelectric (PE) layers realize mutual transformation of magnetic and electric fields and form the basis for the development of highly sensitive magnetic field sensors, electrically tuned electronic components, and energy harvesting devices. ME effects result from a combination of magnetostriction of the FM layer and piezoelectricity in the PE layer due to mechanical coupling between the layers. In this work ME effects are studied in a flexible heterostructure containing a magnetostrictive fiber composite (MFC) and a piezopolymer layer. MFC is a set of microwires made of amorphous FeCoSiB alloy with high magnetostriction and arranged in a plane parallel to each other in a polymer matrix. MFC exhibits strong in-plane anisotropy of magnetization and magnetostriction resulting from demagnetization effects in microwires. Anisotropy leads to the dependence of the linear and nonlinear ME effects characteristics on the orientation of dc magnetic field in the plane of the heterostructure. For the fabricated heterostructure at the resonance frequency of bending vibrations, a linear ME coefficient of 24 V (Oe∙cm)−1 was obtained, and the efficiency of nonlinear generation of the second voltage harmonic reached 1.6 V (Oe2∙cm)−1. ME effects in MFC heterostructures can be used to create magnetic field sensors and electronic devices that are sensitive to the field orientation.
Insights of anisotropic compact stellar structures in f(R, T) theory
Authors: Naseer Tayyab , Sharif M , Chand Fatima
Published: November 2024

This study formulates two distinct non-singular interior solutions that characterize anisotropic spherical structures in the context of f(R, T) theory. We formulate the modified Einstein field equations alongside the corresponding anisotropic factor associated with a static interior spacetime. The field equations are then addressed by implementing two unique constraints that facilitate to solve a system. By adopting specific forms of pressure anisotropy, we derive two different solutions. In both scenarios, we encounter differential equations whose solutions incorporate integration constants which are determined by equating the metric functions of an interior metric with those of the Schwarzschild exterior metric at the boundary of the sphere. The condition of zero radial pressure at the hypersurface also plays a crucial role in this regard. Subsequently, we explore specific conditions that, when met, yield physically feasible compact models. To graphically assess them, we take into account the estimated data of a star, namely SAX J 1808.4-3658 along with different values of the model parameter. Our findings indicate that both stellar solutions align well with the physically existence criteria under certain parametric values.
Mass transport in brain cells: integer-order and fractional-order modeling
Authors: Shit Abhijit , Bora Swaroop Nandan
Published: November 2024

This work successfully elucidates the process of mass transport to brain tissues in a mathematical framework by considering two concepts of porosity and tortuosity in terms of both integer-order and fractional-order models. Henceforth, the analytical solutions to the mass transport model are also obtained to find the response functions by means of which the transport process becomes quite explicit. For better insight into the transport process, a graphical analysis is taken into account. The newly-developed fractional version not only presents better-suited analytical solutions to the model but additionally the graphs also show the matching of the solutions for both integer-order and fractional models. Based on the approximation for four sets of experimental data made by the analytical solution through the means of graphical and numerical results, the fractional model also leads to the selection of the best possible values of the fractional order. We also establish the credibility of the fractional-order model in approximating a wide class of experimental data taken from the laboratory. All the observations clearly establish the superiority of fractional model over the integer-order one.
Effect of interstitial nitrogen on physical and mechanical properties of Al0.5CoCrNi high-entropy alloys: a first-principles study
Authors: Jin Hao , Chen Yanru , Fang Qihong , Li Jia
Published: November 2024

The N-doped high entropy alloys (HEAs) have recently garnered significant interest for their outstanding mechanical properties, making them valuable structural materials within the industry, aerospace, and biomedical science. In this work, the impact of interstitial N atom on various properties of Al0.5CoCrNi HEA is investigated through first-principle calculations. Specifically, the changes in lattice constant, formation energy, elastic modulus, density of states, Vickers hardness, Debye temperature, energy factor, and charge density caused by the presence of interstitial N atom are analyzed. The results show that the interstitial N atoms lead to a decrease of the sample stability due to an increasing formation energy of the N-doped HEA. As the interstitial N content increases, the elastic module decreases, and an apparent anisotropy appears in N-doped HEA. Moreover, Vickers hardness decreases, suggesting the change of the stiffness and deformation characteristics. Compared to the N-doped tetrahedrons, the N-doped octahedrons exhibit high ductility due to an increasing Poisson’s ratio, a decreasing G/B ratio, and an increasing Cauchy pressure. The significant decreasing Debye temperature and average sound velocity reduces the thermal stability. The change of the electronic structure suggests the possibility for customizing electronic and optical properties. Additionally, the low energy factors for screw and edge dislocations promote dislocation nucleation in N-doped HEA. Charge density analysis reveals strong bonding characteristics, potentially affecting the chemical stability and reactivity. This work provides a unique perspective on the N-doped mechanical mechanism, and offers important insights for the advancement of advanced N-doped HEA.
Tomography of flavoured leptogenesis with primordial blue gravitational waves
Authors: Chianese Marco , Datta Satyabrata , Samanta Rome , Saviano Ninetta
Published: November 2024

We explore a scenario where an early epoch of matter domination is driven by the mass scale MN
of the right-handed neutrinos, which also characterizes the different flavour regimes of leptogenesis. Such a matter-domination epoch gives rise to peculiar spectral imprints on primordial Gravitational Waves (GWs) produced during inflation. We point out that the characteristic spectral features are detectable in multiple frequency bands with current and future GW experiments in case of Blue GWs (BGWs) described by a power-law with a positive spectral index (nT
> 0) and an amplitude compatible with Cosmic Microwave Background (CMB) measurements at the CMB scale. We find that the three-flavour leptogenesis regime with MN
≲ 109 GeV imprints BGWs more prominently than the two-flavour and one-flavour regimes characterized by a higher right-handed neutrino mass. In particular, a two-flavour (three-flavour) leptogenesis regime is expected to leave distinct imprints in the mHz–Hz (μHz–mHz) band. Moreover, we translate the current Big Bang Nucleosynthesis (BBN) and LIGO limits on the GW energy density into constraints on the flavour leptogenesis parameter space for different GW spectral indices nT
. We provide a rigorous statistical analysis of how the future GW detectors would be conjointly able to distinguish the flavour regimes. Interestingly, the scenario also offers unique GW signals testable in the next LIGO run with a correlated signature in the PTA frequency band with an amplitude comparable to the one expected from supermassive black holes.
Unmanned unexploded ordnance detection system based on magnetic method
Authors: Xu Y L , Zhou Y J , Ding K , Lv R Q , Wu M W , Wang Z
Published: November 2024

Magnetic method is one of the main methods of UXO detection. This paper uses cesium optical pump magnetic detection module combined with UAV to build an unmanned UXO detection system, and introduces the detection principle and composition of the system. At the same time, the system is used to detect four kinds of UXO targets. The test results show that the system can detect ferromagnetic UXO targets, and can locate the position of UXO targets through magnetic anomaly images. Finally, the limit detection range of four kinds of targets is tested, and the limit detection range of 155 projectiles can reach 4.5m, which meets the actual detection requirements
Ground-penetrating radar dual-parameter full waveform inversion based on finite domain method
Authors: Li B , Fang Z , Feng D , Wang X
Published: November 2024

Ground penetrating radar (GPR) is a crucial method for shallow geophysical exploration method. GPR full waveform inversion (FWI) utilizes all available information including dynamics and kinematics, and theoretically achieving the highest imaging accuracy. However, a significant challenge for FWI is its low computational efficiency, which fails to meet the real-time requirements in actual exploration. To address this issue, we propose a finite domain method (FDM) based on the attenuation characteristic of high frequency GPR electromagnetic waves. This approach limits the calculation to a finite domain, thereby mitigating the excessive computational burden. We determine the size of the finite domain from absorption attenuation, wavefront diffusion, and scattering loss. Numerical experiments demonstrate that compared with traditional FWI, FWI based on FDM reduces the calculation time by more than 5 times.
A compact air-coupled SFCW ground penetrating radar and its application in the earthen sites
Authors: Ye Shengbo , Li Xu , Li Xinhui , Liu Xiaojun , Fang Guangyou , Jiang Hejun , Lyu Rongqi
Published: November 2024

As a non-destructive testing technology, ground-penetrating radar (GPR) has been widely used in archaeological investigations of the earthen sites. Traditionally, a GPR antenna is ground-couple. It is attached to the measured object and thus may cause damage to the earthen sites. This paper develops a lightweight and compact air-coupled stepped frequency continuous waveform (SFCW) GPR system with frequency range from 1GHz up to 6GHz. We suppress the nonlinear variables of the radar system by calibration. And we perform tests on different weathering samples from the earthen sites. Our system is verified that can discriminate layered structures in samples and the results of tests are consistent with the simulations of the gprMax model. In general, this radar system can assess the weathering degree and provide technical support for the preservation of the earthen sites.
Characterization of GPR radiation pattern in the upper and lower hemisphere (theory and experiment)
Authors: Morozov P , Prokopovich I , Lazarev M , Popov A , Sakhterov V , Edemsky D
Published: November 2024

The directivity pattern of a powerful GPR has been studied in archeological works. The methods used: return pulse measurements by passing a compact underground object, multiple passages with changing antennas azimuth for estimating the horizontal directivity, use of a prolonged overhead object in order to estimate spurious radiation into the upper hemisphere.
An intelligent power management system design of ground penetrating radar
Authors: Geng Hongyan , Gengv Yijun , Che Huiying , Chen Qiuyuan , Huang Shanshan , Ding Minggang , Liu Yun
Published: November 2024

A method for the design of an intelligent power management system for Ground Penetrating Radar (GPR) is presented in this article. For the mobile devices which are dependent on their battery power supply, the power management system is vital. The circuit design adopts a voltage stabilizer chip with low-loss and high-efficiency, greatly improving the equipment’s continuous operating time. The power management system also provides the functions as follows: battery charging and discharging automatically switching; providing stable, intelligent and controllable power supply to subsequent circuits; the power differential mode, common mode filtering and π filtering significantly decrease the power noise and enhance the stability of the devices; the power supply circuit is designed with anti-reverse insertion and overheat protection functions, which can prevent the equipment from working within the fault and abnormal temperature range and reduce the risk of equipment failure.
Numerical simulation and dispersion inversion of ground penetrating radar waveguide
Authors: Zhang Kaiwen , Li Jing , Sun Ruizhe , Liu Tieyu , Bai Lige
Published: November 2024

Ground penetrating radar (GPR) is widely used in near-surface detection due to its non-destructive and high-efficiency advantages. Radar waves are continuously reflected in the waveguide structure, and dispersion will be formed. In order to find out the propagation regularity and characteristics of radar waves in waveguides, we use the simulation and field GPR waveguide data to test the radar wave dispersion characteristic. Then, the Dix-type inversion method is used to estimate the permittivity from the radar wave dispersion curve. The synthetic and field data tests show that the GPR waveguide dispersion inversion can accurately estimate the permittivity result.
Lunar surface permittivity distribution along route of Yutu-2 rover
Authors: Du W , Su Y , Dai S , Ding C Y
Published: November 2024

On January 3, 2019, Chang’E-4 (CE-4) landed in the Von Kármán crater within the South pole-Aitken Basin on the Moon’s farside. The lunar penetrating radar (LPR) onboard the Yutu-2 rover is the same as the Chang ‘E-3 mission, which can obtain information about the thickness and strutures of lunar regolith as well as upper crust along the excursion path. The permittivity of lunar material is one of the important parameters for interpreting radar data and can also be obtained by LPR. In this paper, we use the metal plate reflection method based on LPR data and panoramic camera (PC) data to estimate the relative permittivity distribution of 1373m route during the first 53 lunar days. We estimated an average relative permittivity of ~2.78, which is less than ~2.9 of Chang’E-3 (CE-3).
A quantitative method for hesitant linguistic terms based on the grey confidence degree
Authors: Zou Xin , Hao Jingjing , Liu Yuan , Yang Zhuozhuo
Published: November 2024

The study proposes a quantitative method that combines linguistic preferences and confidence levels from different experts by utilizing the concepts of grey information and hesitant fuzzy linguistic information. The developed model transforms hesitant fuzzy linguistic terms into crisp numerical values, enhancing the accuracy of evaluations.
Investigation of early warning of EMG on human G-LOC under centrifuge high G load
Authors: Li Yifeng , Yang Jinghui , Li Baohui , Jin Zhao , Zhang Lihui , Yang Minghao
Published: November 2024

This paper first briefly introduces the early warning indicators and techniques of G-induced human loss of consciousness that is G-LOC under G load action,and puts forward the necessity of exploring and studying EMG signal under G load. EMG signals of the human body are obtained from the human centrifuge, and EMG under G load is analyzed by using the two-condition analysis method in foreign literature. Different from the research in foreign literature, in addition to studying the EMG characteristics under centrifuge G load, the change characteristics of EMG at other muscles are also investigated. The effectiveness of EMG for early warning of G-LOC is explored. The result verifies the efficiency of the two-condition analysis method, suggesting that the specific parameters at the particular parts show characteristic change, which is valuable for early warning of G-LOC under high G load. At the same time, it further proves that the EMG change of gastrocnemius is more effective than that of tibialis anterior. The study lays a foundation for the follow-up research on monitoring and early warning technology of G-LOC by EMG and has important reference value.
Effect of the septal dissection on the distribution of the residual oil
Authors: Liu Zhenyu , Tang Yong , Yang Yan , Yang Zhao , Qu Changyue
Published: November 2024

In order to explore the influence of the interlayer on residual oil, the LZ block in Songliao Basin was selected as the target, and the influence of macroscopic and interlayer location on the distribution of residual oil was studied through a streamlined method and numerical simulation. Among them, the distribution models of 9 types were established according to the position of the interlayer. The study shows that the interlayer greatly influences the enrichment degree of residual oil. Large interlayer plays an obvious role in layered water injection in the medium and low water content stages. In the high water content stage, the higher the position is, the more obvious the effect is. At the same reservoir thickness, the larger the interlayer size is, the stronger the retention effect of the 2PV interlayer on the remaining oil is. At different reservoir thickness, the greater the reservoir thickness is, the lower the integrated water content of the interlayer under 2PV is, and the higher the degree of extraction is, the weaker the residual oil retention effect is.
The H1-error analysis of the reduced-order extrapolated method for parabolic equation
Authors: Liu Guoliang , Xu Wenwen , Li Xindong , Liu Jiacheng
Published: November 2024

In this study, we focus on the proper orthogonal decomposition reduced-order extrapolated technique in the backward Euler finite element (BEFE) method applied to parabolic equation to improve the solving efficiency. We begin by presenting the BEFE method for our given problem, including the existential stability and the H
1-error estimates about the BEFE numerical approximation. Next, we construct the reduced-order extrapolated finite element (ROEFE) matrix model based on the proper orthogonal decomposition reduced-order extrapolated technique. We then prove the existential stability and H
1-norm error estimates for the ROEFE model solutions using norm theory. Our results demonstrate that the precision of the ROEFE model matches that of the BEFE method in the same order, while significantly reducing CPU time under the same time step. Lastly, the numerical case verifies the feasibility and superiority of the ROEFE matrix model over traditional methods.
Research on multi-submersible positioning prediction based on Kalman filter and LSTM neural network
Authors: Miao Yajie , Li Boyi , Guo Xinjing
Published: November 2024

Accurately predicting submarine positions is critical to ensure safe underwater navigation, especially in complex and dynamic marine environments. Traditional methods, such as the Kalman Filter, have been widely used in this area because of their ability to provide optimal state estimates by integrating dynamic models with sensor measurements. However, the Kalman Filter’s effectiveness diminishes in the face of the diverse and non-linear conditions present in underwater environments. This research proposes an enhanced prediction model that combines the Kalman Filter with Long Short-Term Memory (LSTM) neural networks to address these limitations. The proposed model leverages the strengths of both approaches: the recursive, real-time estimation capabilities of the Kalman Filter and the temporal dependency handling of LSTM networks. Through extensive simulations, the model performs better in predicting the three-dimensional trajectories of submersibles, accounting for uncertainties such as ocean currents and varying environmental conditions. The results indicate that this hybrid approach improves prediction accuracy and enhances adaptability and robustness in challenging marine scenarios. This study contributes to developing more reliable submersible positioning systems with potential applications in deep-sea exploration, underwater archaeology, and search and rescue operations.
Multi-agent cooperative encirclement based on improved MADDPG algorithm
Authors: Ai Ling , Tang Shaozhen , Yu Jie
Published: November 2024

In this paper, we propose an improved Multi-agent Deep Deterministic Policy Gradient algorithm with a Priority Experience Replay mechanism (PER-MADDPG) to address the baseline algorithm’s high-dimensional state space challenges in multi-agent encirclement scenarios. The PER mechanism effectively mitigates the issue of non-stationary experience data distribution. By incorporating the Apollonian circle theory, we design an effective encirclement reward function that enables the multi-agent system to complete encirclement tasks in environments with static obstacles. Comparative simulation results show that the improved algorithm achieves faster reward value growth and higher average rewards.
A network clustering algorithm based on the directionality characterization of network dissimilarity
Authors: Jiang Yuanxiang , Ding Nan , Shen Yanli , Zou Yanni , Li Meng
Published: November 2024

Each network or a class of networks often presents specific topological structures. These features describe the relationship between nodes or edges, which directly affects the functionality of the network. Network clustering, as one of the most classical analyses of networks, is highly dependent on the characterization of topological structures and the quantification of network dissimilarity. Given that the existing methods describing the network dissimilarities only consider the difference values but ignore the direction, this paper first proposes a network characterization method based on P-vector for revealing the directionality of network distance. Further, we propose a layout algorithm for multiple networks in a two-dimensional plane and put forward a new network clustering algorithm. The experiments and results indicate the availability and effectiveness of the new proposed methods.
ASO-S orbit evolution and its safety analyses
Authors: Jiang Hu , Zhu Cheng , Deng Lei , Cao Caixia , Bao Haichao , Chen Binglong , Zhang Ye , Li Xinyu , Yang Zhongguang , Yang Yong
Published: November 2024

Advanced space-based solar observatory (short for ASO-S) is one of the space projects sponsored by the Chinese Academy of Sciences; its main scientific goals are to monitor the solar activities during the solar maximal years and to aim at some discoveries of such solar activities as coronal mass ejection, solar flares, and sun spots. The main orbit element variations were simulated based on the online available data set of orbit elements for the satellite ASO-S. Furthermore, based on SOCRATES Plus software, the close approaching objects in space were simulated for satellite ASO-S. These objects are the focused points that might threaten the integrity of satellite ASO-S.
Assessing fire danger classes and extreme thresholds of the Canadian Fire Weather Index across global environmental zones: a review
Authors: Kudláčková Lucie , Bartošová Lenka , Linda Rostislav , Bláhová Monika , Poděbradská Markéta , Fischer Milan , Balek Jan , Žalud Zdeněk , Trnka Miroslav
Published: November 2024

Fire weather indices are one of the basic components of any fire danger early warning system. The Canadian Fire Weather Index (FWI) was developed to indicate the danger due to wildfires in boreal and temperate forests in Canada in the second half of the 20th century. Over time, the FWI has been adapted all over the world and is considered the most widely used fire weather index. This study provides a comprehensive review and meta-analysis of 750 research papers, generalizing the adoption of the FWI across 18 global environmental zones. The objective was to determine FWI values for various fire danger classes worldwide, from very low to extreme. The values of FWI and hydrometeorological variables were compared with wildfire occurrence. Key findings indicate that in drier and warmer climates, higher FWI values (around 50) correspond to high fire danger, whereas in cooler and moister climates, lower FWI values (around 25) signify extreme danger. The analysis of hydrometeorological variables reveals that relative humidity, aridity index, and vapor pressure deficit are significant factors influencing extreme minimum FWI, while average solar radiation has minimal impact. These insights have critical implications for developing effective wildfire prevention and management strategies tailored to specific environmental conditions. By establishing new fire danger classes reflective of regional meteorological and hydroclimatic characteristics, this study enhances the global applicability of the FWI. The ability to quickly adapt the FWI for fire danger forecasting in new areas is particularly beneficial for regions with previously low study coverage. The results underscore the importance of integrating regional climate variables into fire danger assessment frameworks to improve early warning systems and mitigate wildfire risks. The conclusions highlights the effectiveness of the FWI in diverse geographic contexts and its potential to enhance fire danger forecasting globally, thereby aiding in the prevention and management of wildfires.
Warming of newly-subducted subtropical mode water in the North Pacific was suppressed from 1999 to 2017
Authors: Zhang Xueyang , Xu Fanghua
Published: November 2024

Subtropical mode waters are important water masses influencing the regional and global climate. By tracing water masses from the mixed layer into the deeper ocean in late winter, we identified the newly-subducted North Pacific Subtropical Mode Water (NPSTMW) and therefore investigated its temperature changes. The temperature of newly-subducted NPSTMW showed significant warming during 1981–1999, but the warming was suppressed during 1999–2017. The newly-subducted NPSTMW temperature generally agreed with the March–April mixed layer temperature in the subduction region, but was half a degree lower. A mixed layer heat budget analysis indicates that the suppressed warming was caused by the combination of reduced warming effects of shortwave radiation due to the deepened mixed layer, strengthening of sea surface latent heat loss due to the warmer sea surface and enhanced cooling effects of vertical entrainment due to the strengthened subsurface stratification in the subduction region. Our results imply that the oceanic response to global warming can exert a cooling effect on the newly-subducted NPSTMW through these three mechanisms. The shift in trends of the newly-subducted NPSTMW temperature has important implications for the climate variabilities and the marine ecosystem in the North Pacific.
Nonstationary linkage between summer warmth index and NDVI at high latitudes in Eurasia
Authors: Ji Liuqing , Fan Ke , Tian Yuqing
Published: November 2024

The global increase in vegetation photosynthetic activity under the warming climate, commonly referred to as ‘greening’, has been a hot topic, especially in the high latitudes. However, in this study, it was found that, within the region of 60°–70°N and 110°–150° E, the interannual relationship between summer normalized difference vegetation index (NDVI) and summer warmth index (SWI) changes from being statistically positive in P1 (1982–2010) to statistically negative in P2 (2011–2021). Also, the interannual relationship between summer NDVI and summer soil moisture changes from being negative in P1 to positive in P2. The reason and possible mechanisms were investigated. On the one hand, the atmospheric vapor pressure deficit (VPD) has increased significantly in P2 corresponding to the increasing SWI, and the interannual relationship between the VPD and NDVI transforms into a significantly negative one. This is because, when the atmospheric VPD increases, leaf and canopy photosynthetic rates decline owing to stomatal closure, to protect vegetation from losing too much water. Therefore, the interannual relationship between the NDVI and VPD, and in turn the SWI, transforms into a significantly negative one in P2. On the other hand, it was found that the surface evapotranspiration is energy-limited in P1, but then with the decreasing soil moisture content it becomes soil-moisture-limited in P2. As one of the most important components of surface evapotranspiration, vegetation evapotranspiration is also limited by soil moisture. Therefore, the interannual relationship between soil moisture and NDVI becomes significantly positive in P2.
Nonlocality of the energy density of a spontaneously emitted single-photon from a Hydrogen atom
Authors: Federico M , Jauslin H R
Published: November 2024

We analyze through the expectation value of the energy density the spatial nonlocality of single photons emitted by the spontaneous decay of a Hydrogen atom. By using a minimal coupling between the quantized electromagnetic field and the atom, we compute the state of the photon under the assumption that only a single-photon is produced. The calculations are thus performed in the subspace of single-photon states which is essentially equivalent to the rotating wave approximation. We obtain a characterization of the spatial decay of the energy density. We compute the asymptotic limit of large distances from the atom at each given time, and find an algebraic behavior of

1

/

r
6

. This result confirms that the energy density of single-photon states is nonlocal and the algebraic decay is far from the maximal quasiexponential localization predicted by the theory.
Bifurcation analysis of figure-eight choreography in the three-body problem based on crystallographic point groups
Authors: Fukuda Hiroshi , Ozaki Hiroshi
Published: November 2024

The bifurcation of figure-eight choreography is analyzed by its symmetry group based on the variational principle of the action. The irreducible representations determine the symmetry and the dimension of the Lyapunov–Schmidt reduced action, which yields four types of bifurcations in the sequence of the bifurcation cascade. Type 1 bifurcation, represented by trivial representation, bifurcates two solutions. Type 2, by non-trivial one-dimensional representation, bifurcates two congruent solutions. Type 3 and 4, by two-dimensional irreducible representations, bifurcate two sets of three and six congruent solutions, respectively. We analyze numerical bifurcation solutions previously published and four new ones: non-symmetric choreographic solution of type 2, non-planar solution of type 2, y-axis symmetric solution of type 3, and non-symmetric solution of type 4.
The rise of intelligent adaptive metasurfaces
Authors: Qian Chao , Chen Hongsheng
Published: November 2024

Modern-day data science, together with physical science, is reshaping the landscape of artificial electromagnetic media—metasurfaces—on a scale not seen before. Such interaction excels in computationally intensive tasks and real-world applications, such as inverse design, spectral analysis, autonomous devices, and neuromorphic computing. Here, we foreground the rise of intelligent adaptive metasurfaces that are renovating our understanding and utilization of metasurfaces, moving away from human-based control toward automatic control for real-time updates of application requirements. To make the most of these emerging opportunities, we also comment on the perspectives of intelligent adaptive metasurfaces.
Chemical synthesis and analytical profiling of NTSH: a versatile probe for hydrogen sulfide sensing and cellular imaging
Authors: M Ranjana , Kashyap Namita N , Mitra Prajoy Kumar , Sunil Dhanya , Y N Sudhakar , Vennapusa Sivaranjana Reddy , Raju Ramesh , Tittonen Ilkka , Upadhya Dinesh
Published: November 2024

The development of novel probes featuring diverse structural motifs, with promising applications in H2S detection and cellular imaging remains a central focus of scientific research. This study details the synthesis of 4-methyl-N-(6-nitro-1,3-dioxo-1H-benzo[de]isoquinolin-2(3H)-yl)benzenesulfonamide (NTSH), which involves a condensation reaction between commercially available 4-nitro-1,8-naphthalic anhydride and p-toluenesulfonyl hydrazide in glacial acetic acid. The H2S probe exhibits detection limits of 166 μM in fluorometric, 15.08 mM in absorbance, 2.48 mM in colorimetric, and 29 nM in electrochemical studies. The versatility of NTSH in sensing endogenous H2S and bioimaging of HEK 293T cells highlights its potential applicability in chemical biology research. The tendency of NTSH to undergo chemical changes in the presence of H2S to induce noticeable optical and electrochemical responses could lay the groundwork for creating sensitive and selective sensing platforms.
Assessment of surface quality and damages induced during dry helical milling of hybrid composite fiber metal laminates
Authors: Baloor Satish Shenoy , Cagan Suleyman Cinar , Bolar Gururaj , Balkundhi Madhusudhan , Dinesh Anoop Aroor
Published: November 2024

The present work investigates the effectiveness of helical milling for making holes with excellent surface quality in carbon fiber aluminum laminates (CARALL) under dry cutting conditions. The impact of cutting speed and axial pitch on hole surface quality was analyzed. The findings show that axial pitch and cutting speed have a major impact on surface roughness. Utilization of lower cutting speed (30 m min−1) and axial pitch (0.1 mm rev−1) results in material adhesion and feed marks, thus lowering the surface roughness. Nevertheless, the surface finish was enhanced by using higher levels of process variables. Surface defects like chip adhesions, deformation marks, and material smearing were observed. The orientation of the cutting edge with the fibers greatly influenced the surface morphology. Exposed fibers with varying lengths were noted when machining fiber layers oriented at 135°, thus creating an irregular surface. Scanning Electron Microscopic observation of the carbon fiber layers displayed a cleanly cut surface without fiber pullout and crack or interlayer burrs. Moreover, the holes in the CARALL were devoid of delamination/debonding for all the combinations of process variables. In general, results demonstrate the suitability of helical milling for processing holes with superior surface quality and satisfying the stringent requirements of the aircraft industries.
Synthesis of naringenin schiff base loaded CMC/PVA scaffold as biodegradable wound care materials
Authors: Rajesh R Udaya , K S Sachin , Gopakumar Anagha Bijili , Koshy Jijo Thomas , Sangeetha D
Published: November 2024

The complex formula of wound care therapy includes effective treatment tactics, infection prevention, wound preconditioning, and germ therapy. By creating ideal circumstances for wound healing, wound dressings are a major factor in lowering the rate at which infections worsen. The persistence of chronic wounds as a significant healthcare challenge necessitates the creation of innovative wound-dressing techniques. This work describes a novel method for creating ternary biodegradable polymers from polyvinyl alcohol (PVA) and carboxymethylcellulose (CMC). With the addition of naringenin Schiff base, the aqueous mixture of CMC and PVA creates an ideal wound dressing material. The naringenin-derived Schiff base demonstrates strong antibacterial and antioxidant activities. The goal of this work is to create, polymer based on polyvinyl alcohol (PVA) and carboxymethylcellulose (CMC) loaded with Naringenin Schiff base for efficient wound care therapy. The 1H, 13C NMR, FT-IR, and mass spectrometry were used to characterize the Schiff base. The Schiff Base loaded CMC/PVA film was characterized by FT-IR, AFM. Studies such as biodegradability, antimicrobial studies, water absorption capabilities, water vapour transmission rate and dressing pH of the films were also conducted. The promise of biopolymers as better wound dressing material will be highlighted in this work, allowing more efficient wound care.
Overview of the physics design of the EHL-2 spherical torus
Authors: LIANG 梁 Yunfeng 云峰 , XIE 谢 Huasheng 华生 , SHI 石 Yuejiang 跃江 , GU 顾 Xiang 翔 , JIANG 姜 Xinchen 欣辰 , DONG 董 Lili 力立 , WANG 王 Xueyun 雪韵 , YANG 杨 Danke 丹可 , LIU 刘 Wenjun 文军 , SUN 孙 Tiantian 恬恬 , WANG 王 Yumin 嵎民 , LI 李 Zhi 直 , CAI 蔡 Jianqing 剑青 , SONG 宋 Xianming 显明 , TAN 谭 Muzhi 沐芝 , YANG 杨 Guang 光 , ZHAO 赵 Hanyue 寒月 , DONG 董 Jiaqi 家齐 , PENG 彭 Yueng-Kay Martin 元凯 , SONG 宋 Shaodong 绍栋 , CHEN 陈 Zhengyuan 正元 , LI 李 Yingying 颖颖 , LIU 刘 Bing 兵 , LUO 罗 Di 迪 , YANG 杨 Yuanming 圆明 , LIU 刘 Minsheng 敏胜 , Team the EHL-2
Published: November 2024

ENN is planning the next generation experimental device EHL-2 with the goal to verify the thermal reaction rates of p-11B fusion, establish spherical torus/tokamak experimental scaling laws at 10’s keV ion temperature, and provide a design basis for subsequent experiments to test and realize the p-11B fusion burning plasma. Based on 0-dimensional (0-D) system design and 1.5-dimensional transport modelling analyses, the main target parameters of EHL-2 have been basically determined, including the plasma major radius, R
0, of 1.05 m, the aspect ratio, A, of 1.85, the maximum central toroidal magnetic field strength, B
0, of 3 T, and the plasma toroidal current, I
p, of 3 MA. The main heating system will be the neutral beam injection at a total power of 17 MW. In addition, 6 MW of electron cyclotron resonance heating will serve as the main means of local current drive and MHD instabilities control. The physics design of EHL-2 is focused on addressing three main operating scenarios, i.e., (1) high ion temperature scenario, (2) high-performance steady-state scenario and (3) high triple product scenario. Each scenario will integrate solutions to different important issues, including equilibrium configuration, heating and current drive, confinement and transport, MHD instability, p-11B fusion reaction, plasma-wall interactions, etc. Beyond that, there are several unique and significant challenges to address, including

establish a plasma with extremely high core ion temperature (T
i,0 > 30 keV), and ensure a large ion-to-electron temperature ratio (T
i,0/T
e,0 > 2), and a boron concentration of 10%‒15% at the plasma core;

realize the start-up by non-inductive current drive and the rise of MA-level plasma toroidal current. This is because the volt-seconds that the central solenoid of the ST can provide are very limited;

achieve divertor heat and particle fluxes control including complete detachment under high P/R (> 20 MW/m) at relatively low electron densities.

This overview will introduce the advanced progress in the physics design of EHL-2.
Post-measurement pairing quantum key distribution with local optical frequency standard
Authors: Ge Chengfang , Zhou Lai , Lin Jinping , Yin Hua-Lei , Zeng Qiang , Yuan Zhiliang
Published: November 2024

The idea of post-measurement coincidence pairing simplifies substantially long-distance, repeater-like quantum key distribution (QKD) by eliminating the need for tracking the differential phase of the users’ lasers. However, optical frequency tracking remains necessary and can become a severe burden in future deployment of multi-node quantum networks. Here, we resolve this problem by referencing each user’s laser to an absolute frequency standard and demonstrate a practical post-measurement pairing QKD with excellent long-term stability. We confirm the setup’s repeater-like behavior and achieve a finite-size secure key rate (SKR) of 15.94 bit s−1 over 504 km fiber, which overcomes the absolute repeaterless bound by 1.28 times. Over a fiber length 100 km, the setup delivers an impressive SKR of 285.68 kbit s−1. Our work paves the way towards an efficient muti-user quantum network with the local frequency standard.
Increases in vegetation cover increase response more to climate change than to human activities in the Baiyangdian watershed
Authors: Gao Jiashan , Yang Jianying
Published: November 2024

Baiyangdian watershed is located in the upstream of Xiongan New Area, and as an important ecological source of the new area, its vegetation cover status has an important impact on the environmental quality and ecological health of the new area. By analysing the spatial and temporal characteristics of vegetation cover in the Baiyangdian watershed, we investigated the response of climate change and human activities to vegetation cover, and revealed the evolution patterns and driving mechanisms of vegetation cover under changing environments. Utilizing the Google Earth Engine (GEE) and Landsat remote sensing images, the normalized difference vegetation index (NDVI) of the Baiyangdian watershed from 1992 to 2022 was extracted. The temporal and spatial characteristics of vegetation cover were determined using Theil-Sen Median and Mann-Kendall analysis, while factors influencing the spatiotemporal changes in vegetation cover in Baiyangdian were explored through correlation and residual analyses reveal the following: (1) Vegetation cover in the study area showed an increasing trend over time, with a spatial increase from northwest to southeast, revealing the recovery of the ecological environment; (2) Vegetation cover was positively correlated with precipitation and temperature, and the effect of temperature on Baiyangdian was greater than that of precipitation; (3) Residual analyses showed that human activities and climate change had an increasing role in contributing to vegetation cover, and that the dominant factor had changed from human activities to climate changes. The residual analysis shows that human activities and climate change are increasing the vegetation cover, and the dominant factor is changing from human activities to climate change. This study provides a scientific basis for the ecological management of Baiyangdian and the construction of forestry engineering.