bluuebunny/crossref_metadata_2025_split huggingface dataset:
Influence of company secretary characteristics on information disclosure violations: evidence from China
Authors: Xiuli Zhu , Semba Hu Dan , Fang Fang 
Published: October 2024

AbstractThis study analyzed data from 1999 to 2015 on Chinese listed companies to examine the impact of the Company Law of the People’s Republic of China (2006) on company secretary characteristics and information violations. A cross-sectional estimation was used to explore the impact of the Company Law (2006) on the status and expertise of Chinese company secretaries and information disclosure violations. Propensity score matching addressed the endogeneity problem caused by sample selection bias. The results showed that the Company Law (2006) significantly enhanced the status and expertise of company secretaries, mitigating information disclosure violations among those with higher status or professional ability. However, the interaction of higher status and professional ability adversely increased information disclosure violations. Improvements in the status and expertise of company secretaries also led to increased internal replacements and reduced external punishment for errant company secretaries. These findings have implications for enhancing the quality of information disclosure and controlling future violations. They are valuable to regulators, boards of directors, and investors.
Cryogenic sapphire optical reference cavity with crystalline coatings at 1 × 10−16 fractional frequency instability
Authors: Valencia Jose , Iskander George , Nardelli Nicholas V. , Leibrandt David R. , Hume David B. 
Published: October 2024

The frequency stability of a laser locked to an optical reference cavity is fundamentally limited by thermal noise in the cavity length. These fluctuations are linked to material dissipation, which depends on both the temperature of the optical components and the material properties. Here, the design and experimental characterization of a sapphire optical cavity operated at 10 K with crystalline coatings at 1069 nm is presented. Theoretical estimates of the thermo-mechanical noise indicate a thermal noise floor below 4.5 × 10−18. Major technical noise contributions including vibrations, temperature fluctuations, and residual amplitude modulation are characterized in detail. The short-term performance is measured via a three-cornered hat analysis with two other cavity-stabilized lasers, yielding a noise floor of 1 × 10−16. The long-term performance is measured against an optical lattice clock, indicating cavity stability at the level of 2 × 10−15 for averaging times up to 10 000 s.
Monte Carlo simulation of an ammonia adsorption refrigeration system based on calcium chloride impregnated nanoporous carbon
Authors: Afify Nasser D. , Sweatman Martin B. 
Published: October 2024

We use Monte Carlo simulations to investigate the effect of incorporating calcium chloride salt into nanoporous carbon on the performance of an ammonia–carbon adsorption refrigeration system. Simulations of ideal carbon slit-pores with pore sizes of 1, 2, and 3 nm, each containing calcium chloride with ion densities of 0.0, 0.25, and 0.5 nm−3, were carried out at temperatures between 0 and 30 °C and ammonia pressures up to 15.0 bar. The results reveal that ideal 1 nm pores are able to achieve a good refrigeration performance using waste heat below 100 °C to drive the process, but adding salt to these pores increases the waste heat temperature required beyond 100 °C. However, ideal 2 nm pores require the addition of 0.25 nm−3 salt to achieve a similar performance, while the 3 nm pores were unable to achieve a satisfactory refrigeration performance. Considering that real nanoporous carbons usually feature a variety of specific adsorption sites and non-ideal geometries that should have a similar impact to adding salt, these results indicate that nanoporous carbons with pores in the range of 1–2 nm are likely to hold the most promise for adsorption refrigeration applications and that the addition of salt may not always be helpful.
Electric dipole polarizabilities and tune-out wavelengths for 23S1 and 33S1 states of Be2+
Authors: Wu Fang-Fei , Qi Xiao-Qiu , Chen Ai-Xi 
Published: October 2024

The electric dipole polarizabilities and the tune-out wavelengths for the n3S1 (n = 2, 3) states of Be2+ are determined through the application of the relativistic full-configuration-interaction approach. Our calculations directly integrate the mass shift operator into the Dirac–Coulomb–Breit Hamiltonian and further assess the quantum electrodynamics (QED) correction to the dynamic dipole polarizabilities using perturbation theory. The results reveal that the static electric dipole polarizability of the 23S1 and 33S1 states, as well as the 93 nm tune-out wavelength of the 23S1 state and the 238 nm tune-out wavelength of the 33S1 state, exhibits a high sensitivity to QED correction, which exceeds 80 ppm, providing a sensitive test for atomic structure theory.
Evaluating non-photochemical quenching (NPQ) kinetics and photosynthetic efficiency in cassava (Manihot esculenta) subjected to variable high light conditions
Authors: Nair Raji Sadasivan , Raju Saravanan , More Sanket Jijabrao , Puthur Jos Thomas , Makasana Jayanti , Ravi Velumani 
Published: October 2024

Light intensity is a critical environmental factor influencing plant growth and development. To survive high light conditions, plants have evolved various protective mechanisms, including non-photochemical quenching (NPQ). However, NPQ can limit effective photosynthetic yield when transitioning to low light conditions. This phenomenon is underexplored in cassava (Manihot esculenta), a starchy storage root crop known for its high biological efficiency and climate resilience. To address this knowledge gap, we assessed the photoprotective abilities and growth responses of six cassava varieties under natural environmental light conditions (control) and intermittent high light (IHL) conditions by adding 900 μmol m−2 s−1 using full-spectrum LED lights, on top of the natural ambient daylight. Our results demonstrated a significant impact of light treatment on aboveground biomass, total crop biomass, chlorophyll a and b content, photosynthetic rate, and NPQ values during transitions from low to high light and vice versa. Notably, cassava variety ‘Sree Suvarna’ exhibited the highest yield under both control and IHL conditions. These findings suggest that screening cassava varieties for their ability to postpone photoinhibition and recover quickly from photoinhibition may enhance photosynthetic performance. Such strategies have important implications for improving the efficiency and resilience of cassava crops, ultimately contributing to sustainable agricultural productivity.
Response of white-tailed deer to removal of invasive wild pigs
Authors: McDonough Matthew T. , Gitzen Robert A. , Zenas Stephen J. , Smith Mark D. , VerCauteren Kurt C. , Ditchkoff Stephen S. 
Published: October 2024

Context With the range expansion of invasive wild pigs (Sus scrofa) in North America during the past decades, there has been an increasing concern with how wild pigs affect native species. An abundance of research on their impacts has been through the lens of damage to anthropogenic resources and plant communities. However, quantitative research on how wild pigs affect populations of native animal species is an understudied topic. Aims Our goal was to assess how wild pigs affect white-tailed deer (Odocoileus virginianus) at a population level by measuring changes in deer abundance as wild pigs are removed. White-tailed deer are an economically valuable game species in North America, and negative impacts of wild pigs on their populations could have trickle-down impacts on conservation funding for all wildlife. Methods On three treatment areas (34.07–55.31 km2) and one control area (25.10 km2), we used N-mixture models to compare data from camera-trap surveys of white-tailed deer before and after wild pigs were removed from treatment areas. Key results We removed 1851 pigs from the treatment sites between May 2019 and March 2021. We found that wild pigs did not significantly affect white-tailed deer abundance, but that white-tailed deer were 1.12 (1.02–1.23; 95% CL) times as likely to be detected when the number of pigs removed was equal to our baseline population estimates compared with when no pigs were removed. Although results from similar analyses on separate age and sex classes of white-tailed deer exhibited similar results, analyses of impacts on immature males differed. Conclusions Our overall results are congruent with those of other research that suggest that wild pigs affect white-tailed deer behaviour at a local scale, although eliminating pigs from an area does not appear to quickly lead to increased abundance of deer. Implications Although the interspecific interactions between white-tailed deer and wild pigs are unlikely to lead to a decline in the population of white-tailed deer, removing wild pigs may decrease the behavioural implications of these interactions.
Self-gravitating matter in stationary and axisymmetric black hole spacetimes
Authors: Kocherlakota Prashant , Narayan Ramesh 
Published: October 2024

AbstractAll black holes (BHs) in nature are expected to be described by the Kerr vacuum solution of general relativity. However, the Kerr BH interior contains several problematic features such as a Cauchy horizon, a curvature singularity, and a causality-violating region. Non-Kerr BH models, which are used to examine the genericity of these features, typically contain nontrivial matter content. When such self-gravitating matter is minimally-coupled to Einstein–Hilbert gravity, the Einstein equations can be directly used to investigate its physical properties. We examine here the properties of matter in a broad class of stationary and axisymmetric, geodesically-integrable BH spacetimes, and how they are linked to various features of the spacetime geometry. In these spacetimes, we find the matter to typically flow along timelike Killing orbits in the BH exterior, usually exhibiting differential rotation but sometimes additionally also non-rigid rotation. At a horizon, the matter rest-frame energy density,ε, and principal normal pressure,pn, are shown to necessarily satisfypn=−ϵ, implying that only specifictypesof matter can thread stationary event horizons (e.g. electromagnetic fields but not massless real scalar fields). Furthermore, we introduce Boyer–Lindquist-like coordinates for the nonstationary regions in the BH interior, which show the matter to be comoving with the interior cosmology. We also obtain simple expressions for the expansions of the ingoing and outgoing zero angular momentum null congruences and comment on the light-focussing behavior of the cosmology. Finally, we verify above results explicitly by working with a representative set of well-known BH spacetimes which contain various types of matter—scalar fields, electromagnetic fields, anisotropic fluids. Some spacetimes have singularities while others have regular interiors. In the exterior, the matter satisfies the weak energy condition. The framework developed here can be extended to cover more general spacetimes.
Non-linear charged dS spacetime and its thermodynamics and Schottky Anomaly
Authors: Zhen Hai-Long , Du Yun-Zhi , Li Huai-Fan , Zhang Li-Chun , Ma Yu-Bo 
Published: October 2024

Abstract
In this paper, firstly, the conditions and existence region for the coexistence of the black hole and cosmological horizons in Non-linear charged dS (NLC-dS) spacetime are discussed, subsequently, the thermodynamic quantities for which the boundary conditions are satisfied in spacetime in the coexistence region of the two horizons are discussed, and the effective thermodynamic quantities in the NLC-dS spacetime in the coexistence region with two horizons are presented. Based on these, the heat capacity in the coexistence region with two horizons is addressed, the behavior of the heat capacity in the NLC-dS spacetime in the aforementioned region is found to exhibit the characteristics of Schottky specific heat. In order to investigate the intrinsic reason of the heat capacity in spacetime, we regard the two horizons in the NLC-dS spacetime as two distinct energy levels, consequently, the microscopic particles at different horizons exhibit disparate energies. Using the heat capacity relationship between the two-energy levels in an ordinary thermodynamic system, the heat capacity in dS spacetime is discussed, it is observed that the behavior of the heat capacity is analogous to that of the two-energy levels in an ordinary thermodynamic system. The number of microscopic particles in the two-energy-level system are approximated by comparing the maximum value of the heat capacity of the system with the maximum value obtained by treating the two horizons in the NLC-dS spacetime as a two-energy-level system of two distinct energies. This conclusion reflects the quantum properties of the coexistence region with two horizons in the NLC-dS spacetime. It provides a new avenue for further study of the thermodynamic properties of black holes and the quantum properties of de Sitter spacetime.
Flattenicity as centrality estimator in p–Pb collisions simulated with PYTHIA/Angantyr
Authors: Ortiz Antonio , Bencédi Gyula , Fan Feng 
Published: October 2024

Abstract
In this paper, a centrality estimator based on flattenicity is studied using PYTHIA 8.312 Angantyr, whose existing implementation is enough to study the particle production in p–Pb collisions in the absence of medium effects. The number of binary nucleon–nucleon collisions for different centrality estimators are compared. The studies include forward multiplicity, forward flattenicity and midrapidity multiplicity. The results using flattenicity show the smallest deviations (<8%) with respect to the results which use impact parameter for centrality classes. On the other hand, the multiplicity-based estimators exhibit huge deviations (up to a factor 2) with respect to the results using impact parameter. The particle ratios (proton-to-pion and kaon-to-pion ratios) and nuclear modification factors as a function of p
T are also studied for the different centrality estimators. The studies presented here are relevant to help in the investigation of the plethora of effects, which have been reported by experiments at the Large Hadron Collider.
Smart dimensional quality assessment of embedded steel plates based on images and laser data fusion
Authors: Li Hangyu , Jiang Shang , Zhang Jian 
Published: October 2024

Abstract
Accurate and efficient positioning is critical to ensuring the dimensional quality assessment of embedded steel plates. However, traditional manual measurement methods struggle to efficiently measure and evaluate these plates. Vision-based measurement methods offer advantages such as high resolution, fast data acquisition, and processing speed, allowing accurate measurement of 2D coordinates. Light Detection and Ranging (LiDAR) can capture highly accurate point clouds, due to the unordered nature of point clouds, processing and analysis require significant computational resources. This paper proposes a method for smart 3D localization of embedded steel plates using image and laser data. (1) We introduce an improved rectangular diagonal constraint Harris corner detection method and achieve subpixel 2D corner detection of embedded plates based on deep learning:(2) given a calibrated camera-LiDAR, we develop a smart detection algorithm guided by 2D image bounding boxes, achieving 3D corner localization. In indoor testing and engineering applications, this method effectively ensures the dimensional quality of embedded steel plates. Compared to traditional manual inspection, the measurement efficiency reaches 10 min per station, with an accuracy of 2.12 mm.
In-situ measurement methods for microscale surface impurities in powder bed fusion: a review
Authors: Koca Ahmet , Hooshmand Helia , Leach Richard , Liu Mingyu 
Published: October 2024

Abstract
Despite ongoing improvements and optimisation efforts, the powder bed fusion (PBF) process continues to face challenges related to repeatability, robustness, and stability. These challenges can lead to the formation of microscale surface impurities on each layer, such as balling, spatter and surface pores, which can adversely affect the overall quality of the final part. The layer-by-layer fabrication approach in PBF offers an opportunity to assess fabrication quality in real-time by detecting these impurities at each layer during the manufacturing process through in-situ sensing methods. With advancements in sensing and computing technologies, there has been a significant increase in studies focused on developing in-situ methods for the real-time detection of surface impurities and feedback mechanisms. However, it is necessary to understand the effectiveness and capability of these in-situ methods in detecting microscale surface impurities, as well as to evaluate their potential advantages, drawbacks, and the existing gaps in the literature. This study first summarises the common microscale surface impurities and their potential impacts on part quality, including mechanical properties and surface finish. It then reviews the existing in-situ methods capable of detecting these microscale impurities, providing insights into the strengths and limitations of current techniques, and identifying gaps in the literature while suggesting directions for future research.
Adaptive IMU error correction algorithm for dual-antenna GNSS/IMU integrated vehicle attitude determination
Authors: Jiang Lei , Sun Rui , Cheng Qi , Yin Tong , Mao Yi 
Published: October 2024

Abstract
In land–based applications, the attitude of a vehicle can be accurately estimated by integrating data from global navigation satellite system (GNSS) and inertial measurement unit (IMU). However, traditional dual-antenna GNSS/IMU integrated systems are susceptible to signal reflection, diffraction, and interruption, leading to reduced accuracy and reliability in GNSS challenging environments. To address these issues, this study introduces an adaptive IMU error correction algorithm for dual-antenna GNSS/IMU integrated vehicle attitude determination. Initially, an IMU-aided baseline length constraint model is developed to enhance the ambiguity resolution performance of the integrated system in signal-degraded areas by incorporating precise prior information from the IMU. Furthermore, an adaptive IMU error correction mechanism based on long short-term memory and particle swarm optimization is proposed to predict the vehicle attitude during GNSS outages and to constrain the attitude error drift measured by lMU. Field test results demonstrate that, compared to two other candidate algorithms, the proposed algorithm improves accuracy in roll, pitch, and yaw by 19.23%, 30.56%, and 67.12%, respectively, and by 12.50%, 10.71%, and 38.39% respectively. Moreover, in two distinct scenarios where GNSS is blocked for 120 s, it was able to consistently deliver accurate and stable vehicle attitude information, maintaining roll, pitch, and yaw accuracy within 0.08 degrees.
Improving PPP timing and time transfer based on signal distortion biases calibration
Authors: Zang Minghui , Gong Xiaopeng , Chen Qusen , Gu Shengfeng , Guo Wenfei , Zhang Weixing 
Published: October 2024

Abstract
Precise point positioning (PPP) technology has been widely used for more than a decade in timing and time transfer. Pseudorange bias caused by signal distortion will reach up ±3 ns, which cannot be neglected in sub-nanosecond level PPP timing and time transfer. We propose to improve the performance of PPP timing and time transfer by considering signal distortion bias (SDB). In principle, SDB will affect PPP timing and time transfer by influencing the initial clock offset. Then, it is verified by theoretical and experimental analyses. The theoretical results show that the impact of SDB on PPP timing can reach up 1.8 ns in different regions. Also, the impact of SDB on time transfer can reach up 0.8 ns in different regions even if the baseline length and receiver types are the same. For experimental results, the accuracy of PPP timing and time transfer improves with SDB correction. For time transfer, the RMSs are reduced by 54.8%, 61.1% and 17.6% for GPS, BDS3 and Galileo in all links, respectively. The clock frequency consistency obtained from different systems has been improved. And the frequency stability of time link with Hydrogen clocks is improved by 53.0% at 10000s interval with SDB correction.
Evaluation of rotating components by combining individual classification with adaptive updating searching method in aero engine
Authors: Yang Runze , Huang Jingzhi , Lian Dongshan , Gao Shouru , Tonghan Lin , Zheng Yixuan , Liu Yongmeng , Tan Jiubin 
Published: October 2024

Abstract
In order to evaluate the roundness error of rotating components in aero engine with increased speed and more accurate estimation, this paper presents an enhanced method that integrates individual classification with adaptive updating searching (ICAUS) strategy. The individual classification method simulates the renewal regulations of various candidate points as iterations increase, subsequently generating new solutions for the next iteration. Additionally, an adaptive updating search zone method that varies in accordance with the increment of iterations is incorporated. These newly generated solutions are distributed within the updated search zone to ensure that the global optimal solution is not overlooked and the search zone is constrained to prevent excessive divergence, thereby enhancing computational efficiency. To validate the efficacy and accuracy of the proposed method, we utilized datasets and conducted comparative experiments using experimental methods previously studied by predecessors. The experimental results and comparisons demonstrate that the proposed ICAUS method exhibits superior convergence characteristics compared to previous studies. Across five distinct datasets, the average computation time satisfying the terminal conditions ranged from 0.0013 s to 0.0018 s, the standard deviation of the roundness was less than 6.2051 × 10–9 mm and the optimal solutions were obtained within 10–20 iterations, achieving the solution accuracy of ϵ= 10–8 mm.