bluuebunny/crossref_metadata_2025_split huggingface dataset:
An alternative recommendation for design eccentricity by consideration of uncoupled frequency ratio
Authors: Akyürek Osman , Ulutaş Hakan 
Published: December 2024

AbstractCivil structures are prone to dynamic loadings such as strong winds or ground excitations where torsion becomes an ongoing issue. This arises from a lack of coincidence of the center of mass (CM) and rigidity (CR), known as eccentricity. Seismic design codes often introduce two types of eccentricity: inherent (geometric) and accidental. To account for structural or ground motion uncertainties, an assumption-based solution is provided by many code provisions, which considers the accidental eccentricity as a percentage (5% or 10%) of the building length perpendicular to the direction of exposed ground motion. In this study, as an alternative way to the code design parameters, a new design eccentricity formula that considers the frequency ratio (torsional frequency/translation frequency) and an effective radius of gyration to account for torsional irregularity is considered. For the extended validation of the proposed method, eighteen model buildings with six different floor plans were chosen, representing low, medium-height, and high-rise buildings. Each floor plan had model buildings with three, seven, and twelve stories. The buildings were subjected to selected bidirectional earthquake ground motions and had time history analyses performed. The results of the proposed method were compared to code provision methods, obtained using equivalent lateral force procedures, and also to those obtained utilizing the time history analysis results. It was shown that the proposed method was more effective in estimating the impact of torsional eccentricity and provided a better understanding of its impact on structural dynamic characteristics.
Revealing exchange bias in spin compensated systems for spintronics applications
Authors: Pal Koustav , Dey Suman , Alam Aftab , Das I. 
Published: December 2024

AbstractAntiferromagnetic materials offer potential for spintronic applications due to their resilience to magnetic field perturbations and lack of stray fields. Achieving exchange bias in these materials is crucial for certain applications; however, discovering such materials remains challenging due to their compensated spin structure. The quest for antiferromagnetic materials with exchange bias became a reality through our experimental study and theoretical simulation on $$\hbox {Sr}_2 \hbox {FeIrO}_6$$

Sr
2

FeIrO
6

and $$\hbox {Sr}_2 \hbox {CoIrO}_6$$

Sr
2

CoIrO
6

. This study also unveils the impact of ionic disorder and lattice distortion on magnetic properties. The presence of exchange bias in both materials, given their antiferromagnetic nature, is intriguing. This study opens up new avenues for achieving exchange bias in spin-compensated systems, offering potential for low power and ultra fast antiferromagnetic spintronic applications in future research endeavors.
Design and investigation of a transparent and actively tunable broadband electromagnetic wave-absorbing metamaterial
Authors: Li Ruilong , Lin Weijiong , Leng Shaoyong , Xu Zhibiao , Wang Ying , Wang Tao 
Published: December 2024

Abstract
With the development of electronic information technology, the demand for electromagnetic wave-absorbing materials with special characteristics such as transparency and tunability has surged. Here, a transparent and actively tunable broadband electromagnetic wave-absorbing metamaterial combined with diodes and indium tin oxide is designed and experimentally realized, achieving a transmittance of 71.9% and an effective absorption (reflection loss (RL) < −10 dB) bandwidth of 10.1 GHz (7.9–18 GHz). The RL of the sample changes from −35.95 dB to −11.53 dB at 9.69 GHz and from −11.11 dB to −42.29 dB at 15.83 GHz when the applied voltage is varied from 10 V to 20 V. In addition, the modulatory mechanisms of the absorption performance are investigated. The tunable RL is attributed to variations in the reflection, transmission and absorption of the metasurface and to the presence of multiple reflection mechanisms, which are essentially related to the electromagnetic coupling effect on the metasurface. This work lays the foundation for the preparation of wave-absorbing materials applicable to special scenarios and provides guidance for the modulation of the absorptive properties of metamaterials.
Research on micro-arc oxidation discharge spark detection technology based on MO-DETR
Authors: Li Fangqiang , Lu Hailin , Zhi Shuangshuang , Zhao Ziyue , Zhou Li , Bai Xiutao , Xu Guangshen , Chen Yongdang 
Published: December 2024

Abstract
During microarc oxidation (MAO), the unique characteristics of the discharge spark have a profound effect on the morphology, structure and surface properties of the oxide film. However, due to the high-pressure environment and the complexity of the spark characteristics, it is difficult to accurately observe and analyze these features by conventional detection methods. To this end, we propose a novel target detection model, MO-DETR, which combines the improved CSPDarknet53 as a backbone and a new lightweight encoder, DEEDP (DASi-enhanced feature diffusion pyramid), to systematically process and fuse multiscale features, reduce model complexity and increase processing speed. MO-DETR uses DETR’s multilayer decoder architecture to achieve real-time detection in multiple scenarios and without retraining. On our homegrown MAO dataset MO-Dataset, MO-DETR achieves an average precision of 92.1% and 135.9 FPS on 1080ti GPUs, which outperforms the Yolo series detectors overall. Compared to RT-DETR, MO-DETR achieves a 1.2% improvement in accuracy (from 90.9% to 92.1%), an 82% reduction in parameter volume (from 31 987 850 to 5 728 600), a 91.6% reduction in arithmetic requirements (from 103.4 GFLOPs to 11.8 GFLOPs), and a 71% speedup on the same task (from 39.6 FPS to 135.9 FPS). These improvements significantly increase performance and reduce hardware requirements, making it more practical for real-world applications.
A meta transfer learning fault diagnosis method for gearbox with few-shot data
Authors: Yang Zhichao , Duan Yudan , She Daoming , Pecht Michael G 
Published: December 2024

Abstract
The gearbox of large-scale mechanical equipment operates under complex working conditions, and its operation and maintenance are crucial to ensure safe production. This paper proposes a fault diagnosis method for gearboxes under variable operating conditions with few-shot data to address the scarcity of data for specific fault types. Firstly, several fault diagnosis tasks are constructed under variable operating conditions. These deep features of different tasks are extracted by a deep convolutional neural network. In the training process, the model adaptively adjusts its parameters and inner loop learning rate, enabling it to acquire domain invariant features. The Batch Spectral Shrinkage is presented to reduce the impact of negative transfer and catastrophic forgetting on model optimization during knowledge transfer. The loss function is reconstructed using the weight balance strategy to mitigate the distribution discrepancy between the source and target domains. Consequently, the Meta-SGD transfer neural network framework enables a fault diagnosis model for gearboxes under variable operating conditions with few-shot data. The experimental datasets of the gearbox verify the effectiveness of the proposed fault diagnosis framework.
Advances in nanomaterials for radiation protection in the aerospace industry: a systematic review
Authors: Sales Antonio Said Webbe , Pereira Vinicius de Queiros , Dias Airton Natanael Coelho 
Published: December 2024

Abstract
Nanomaterials stand out for their exceptional properties and innovative potential, especially in applications that protect against space radiation. They offer an innovative approach to this challenge, demonstrating notable properties of radiation absorption and scattering, as well as flexibility and lightness for the development of protective clothing and equipment. This review details the use of polymeric materials, such as polyimides (PIs), which are efficient at attenuating ultraviolet (UV) radiation and atomic oxygen. For example, PIs show a decrease in elongation at break by 10% after exposure to VUV radiation of 2000 equivalent solar hours. The thermal stability under vacuum UV (VUV) irradiation shows that colorless PIs like colorless aluminized polyimide (CPI)-T/Al exhibit an onset degradation temperature (Tonset) of 451 °C, while CPI-L/Al shows a degradation onset of 439 °C. Additionally, advancements in composite materials for gamma and neutron radiation shielding are covered. Materials such as fluorinated hyperbranched PIs display a decomposition temperature of approximately 450 °C, which ensures structural integrity during space missions involving radiation. Radiation absorption and scattering properties of these composites are assessed, with materials such as W-Bi2O3 demonstrating a high linear attenuation coefficient of 2.5 MeV, enhancing their efficiency in protecting against gamma radiation. Mechanical and optical changes, such as a 15% increase in solar absorbance after exposure to VUV, are critical for prolonged space missions. Moreover, the integration of nanoparticles like graphene and carbon nanotubes into polymers has proven to be an efficient strategy for improving the shielding properties and stability of materials. Nanocomposites like BNTT-Ti display a neutron transmission reduction of 20%, further validating their potential for space applications. Future investigations will focus on optimizing the functionality, manufacturing, and compatibility of composite materials, as well as validating their performance under actual space mission conditions. Collaboration among material scientists, aerospace engineers, and space agencies is vital to transforming laboratory discoveries into viable solutions for radiation protection in space.
Design and simulation of magnetic field sensor based on dual-core photonic crystal fiber filled ferrofluid at different ambient temperatures
Authors: Amiri Tayobeh , Kadivar Erfan , Ghajarpour-Nobandegani Sajad 
Published: December 2024

Abstract
Dual-core photonic crystal fiber (DC-PCF) based on ferrofluid-filled core holes is proposed to detect and measure magnetic field. The suggested magnetic field sensor contains two core holes. The two core holes of photonic crystal fiber are filled by nanoparticle ferrosoferric oxide (Fe
3
O
4) magnetic fluid. The magnetic sensor mode distribution and mode coupling under different values of magnetic field strength and ambient temperatures are studied. Finally, the transmission spectrum and magnetic field sensitivity of the DC-PCF magnetic field sensor are calculated at different ambient temperatures. Our numerical results depict that the present magnetic field sensor could detect magnetic field in the range of 89-271 (Oe), has a good FOM of 450.7 RIU
−1, and shows high sensitivity to 21.9 (μm/RIU) and 35.1 (μm/RIU) for x − and y − polarizations at the room temperature, respectively. It was also found that the magnetic field sensitivity decreases with increasing the ambient temperature.
Features of magnetically induced exceptional points in cholesteric liquid crystals
Authors: Gevorgyan A H , Bulanov A V , Oganesyan K B 
Published: December 2024

Abstract
In this work, the photonic properties of cholesteric liquid crystals (CLCs) in an external magnetic field parallel to the helix axis are investigated for the first time in the short-wavelength band of the spectrum, where exceptional points (EPs) are found. It was shown that at EP the real parts of two of four wave numbers touch each over, and their imaginary parts intersect. Here the reflection, transmission and absorption show the same values for two eigenmodes of CLC layer. At anisotropic absorption near the EP there appear points where the magnetically induced transmittance and absorption are observed. The light localization peculiarities as well as photonic density of states (PDOS) peculiarities near these points were also investigated. Near EPs, PDOS for two eigenmodes shows significant changes, especially with different magneto-optical activity parameters.
Research and Development on a 334 kJ Pulse Power Module for Electromagnetic Launch
Authors: Zhang Y Z , Gao Y , Shi Y L , Zou H B , Li Y M , Qiu X Y 
Published: December 2024

Abstract
As electromagnetic launch technology continues to evolve, the demands on pulse power supply are becoming increasingly stringent. Megajoule-level capacitive energy storage pulse power supply(PPS) are generally composed of several hundred-kilojoule pulse power modules (PPMs) connected in parallel, with the performance of these modules determining the capabilities of the entire PSS. PPMs need to have higher energy storage density, higher peak currents, and the ability to operate continuously to enhance compactness, launch efficiency, and launch frequency. Continuous operation requires improved cooling capabilities in the PPMs. This paper presents the design of an actively cooled pulse power module (PPM) with an energy storage capacity of 334 kJ, a rated operating voltage of 6.67 kV, and an output peak current of approximately 100 kA, achieving an energy density of 1.13 MJ/m3. The module utilizes water cooling, with designed structures for main power components and simulated cooling capabilities under continuous operation. The design discharge frequency can reach up to 10 shots per minute. Ultimately, the module underwent discharge performance tests using a simulated railgun load. The tests confirmed that this actively cooled PPM meets the design specifications, with a compact structure and reliable operation.
Fixed-Time Adaptive Neural Network Compensation Control for Electric Cylinder Erection Systems
Authors: Wang Yancheng , Ma Jiahua , Deng Wenxiang , Yu Xiaochuan 
Published: December 2024

Abstract
This paper proposed a fixed-time adaptive neural network compensation control (FTANN) strategy for electric cylinder erection systems with unknown system dynamics and external time-varying disturbances. This method fully leveraged the estimation capabilities of neural networks and the rapid convergence of fixed-time control. Compared to traditional adaptive fixed-time neural network control methods, the proposed controller exploited the neural network’s ability to approximate arbitrary nonlinear functions, maximizing the neural network’s potential while avoiding the high gain issues that traditional controllers might have encountered. The Lyapunov stability theory was used to prove that the closed-loop system was fixed-time stable, and simulations verified the effectiveness of the proposed method.
The Influence of Magnetic Fields on the Operational State and Velocity of Smart Projectiles
Authors: Guo Zhangxia , Chen Jiahao , Zou Libo 
Published: December 2024

Abstract
The electromagnetic railgun, as a novel launching technology, held great potential for development. However, due to the strong magnetic interference during the launch process, most of the electromagnetic railguns that were being researched at that time could only launch kinetic projectiles. By incorporating magnetic shielding materials within the projectile to mitigate the impact of external magnetic fields on the internal circuitry, it became feasible to launch guided missiles and range-determining projectiles. This advancement could have significantly enhanced the versatility of electromagnetic railguns. The paper established a multi-physical field coupling model between the projectile and the magnetic field using the COMSOL software. First, the shielding efficiency of the shielding body inside the projectile as it passed through a uniform magnetic field was calculated. At the same time, when the projectile moved in the magnetic field, it was subjected to an action force exerted by the magnetic field. The paper studied the force relationship between the projectile and the magnetic field and the deceleration of the projectile, and found that the magnetic field had a role of accelerating the projectile first and then decelerating it. The acceleration stage was much smaller than the deceleration stage. The projectile also generated eddy currents in the magnetic field, causing the temperature of the projectile to rise. The experimental results obtained were basically consistent with the numerical calculation results. Under the shielding effect, the internal circuits of the projectile were greatly reduced by the interference of the magnetic field, and the speed and temperature of the projectile remained within a reasonable range. This also provided certain reference for the design of electromagnetic coil gun muzzle velocity measurement devices and proximity fuse signal transmission devices.
Sensitivity analysis of key parameters of tank stabilization system actuators for muzzle stabilization accuracy
Authors: Lin Darui , Yang Guolai , Yuan Shusen , Wang Yimin 
Published: December 2024

Abstract
This paper proposes a novel global sensitivity analysis method that combines deep neural networks with saltelli estimation, significantly enhancing the efficiency and reliability of sensitivity analysis in complex mechanical systems. Given that sensitivity analysis often requires a large amount of sample data, and the high-precision multi-body dynamics simulation model of tanks inevitably leads to increased computational costs. To address this, based on electromechanical integrated dynamics model of tank stabilization system, a deep neural network surrogate model for muzzle stability accuracy was established. Subsequently, further integrating saltelli estimation, a global sensitivity analysis targeting muzzle stabilization accuracy was conducted by selecting 18 key parameters of the actuator electric cylinder as the object. Finally, a key parameter system of the actuator electric cylinder influencing muzzle stabilization accuracy was established, providing theoretical support for the design optimization of the next generation tank stabilization system.
Clamping and buffering mechanism for large-caliber rocket projectiles based on bistable shells
Authors: Li Zhuangzhuang , Li Xuelin , Guo Zhuoyu , Zhou Yue , Lin JiaHui , Han Shuo , Mo Zonglai , Li Jun 
Published: December 2024

Abstract
Long-range large-caliber rocket projectiles are prone to impact with the rail on the launch box due to overload during transportation. In order to hold the rocket tightly during transportation and quickly separate it during launch, this paper proposes a novel clamping mechanism based on the bistable shells, which can not only provide transportation protection for the rocket projectile but also quickly detach from the rocket projectile. Through numerical study, the force-displacement curve of a single clamping mechanism under instantaneous compression load and the opening process under pneumatic load were analyzed. Based on this, a finite element model simulating the overload during transportation was established to compare the effects with and without the clamping mechanism. The results show that the designed clamping mechanism meets the design expectations, providing excellent protection for the rocket projectile, and allowing for quick opening. This mechanism also has broad application prospects in other fields such as packaging Engineering and soft clamping mechanisms.
Analysis of interval uncertainty response for the ramming coordination mechanism of artillery automatic loading system
Authors: Luo Guiyuan , Chen Guangsong , Li Ang 
Published: December 2024

Abstract
The ramming coordination mechanism is a critical component of the artillery automatic loading system. Its primary function is to receive projectiles from the manipulator and align them parallel to the bore axis, facilitating subsequent chambering of the projectiles. The reliability of the ramming coordination mechanism directly influences the subsequent precision of chambering. Therefore, analysing the boundary response of this mechanism is crucial for subsequent reliability assessments. In response to the issue of interval uncertainty response for the ramming coordination mechanism, this paper proposes a method that combines sequential simulation strategy with rigid-flexible coupled dynamic analysis. First, a ramming coordination mechanism rigid-flexible coupled controlled dynamic model considering clearances is constructed based on its motion principle. Subsequently, the sequential method is employed to solve the boundary response, resulting in the boundary response curve of angular displacement for the ramming coordination mechanism. The results indicate that the method combining sequential simulation with rigid-flexible coupled dynamic analysis can more efficiently solve the boundary response of the mechanism. Moreover, the uncertainty factors present during the initial coordination and velocity mutation moments significantly impact the motion precision of the mechanism, potentially leading to motion failure in severe cases. This provides a reference for the subsequent reliability analysis of the mechanism.
Test on the linear induction launcher with energy storage capacitor and propulsion winding integrated construction
Authors: Wang H Sh , Wang J Ch , Ma B D , Zheng Ch , Bai J , Wen N J , Chen X R , Xue J D , Jin P Y 
Published: December 2024

Abstract
Different from traditional EM coil launcher, a new type of primary construction was brought forward in this paper. The energy storage capacitor and primary winding were integrated into one component. The relevant basic equations of mathematical physics were deduced, the finite element simulation was carried out, and the experimental principle prototype was set up for experimental verification, which proves that the new structure is expected to enable the development of more compact and more efficiency EM coil launcher.
Research on present situation and development of fire strike equipment for mountain operations
Authors: Li Yuxi , Feng Zhanbo , Li Zhengyu , Song Zhenhua 
Published: December 2024

Abstract
Mountainous areas account for a large proportion in China’s border regions. In view of the special terrain and complex meteorological conditions of mountain warfare, mountain firepower strike equipment has become the core key for our military to deal with border conflicts. In order to adapt to the changes in future mountain warfare and lead its development, this paper summarizes and analyzes the performance characteristics and development history of mountain warfare equipment at home and abroad. Combined with the influence of future mountain warfare forms and battlefield environments, characteristics of active equipment and the application of high and new technologies on mountain warfare, the future development goals of mountain firepower strike equipment are prospected, and the technical research directions of mountain firepower strike equipment are proposed in stages according to the strike equipment system structure.
Research on automatic shotgun recoil reduction method and recoil force test
Authors: Zhang Zhenhui , Zhang Huihui , Wang Yong 
Published: December 2024

Abstract
Aiming at the requirement of a 30% reduction in the recoil of the automatic shotgun, the researchers investigated the various thicknesses of the stock rubber, the different hardness of the stock rubber, and the floating buffer mechanism of the gun body. Researchers also conducted the recoil test and comparison to determine the structural scheme for recoil reduction. The test results indicate that the recoil force of the automatic shotgun is reduced by 51.9% compared with that of a fixed shotgun when using NBR (nitrile rubber buna) with a thickness of 20 mm and a hardness of 20 Shore hardness. The technical measures adopted are effective and can meet the requirements of the specified technical indicators.