bluuebunny/crossref_metadata_2025_split huggingface dataset:
Co-Existence of Compressive and Rarefactive Dust Acoustic Solitary Structures in Saturn’s Rings with Non-Maxwellian Ions and Electrons
Authors: Zaidi Syed Ahmad Muzammil , Qureshi M. N. S. , Khalid Saba 
Published: December 2024

Abstract
In the present study, we investigated the existence of arbitrary amplitude dust acoustic (DA) solitons by considering the Cairns distributed ions, negatively charged streaming dust grains along with (r,q) distributed electrons in an un-magnetized dusty plasma. We used the pseudopotential technique to obtain the solitary wave solution. It is seen that the coexistence of rarefactive and compressive solitons is possible when ions and electrons are nonthermally distributed. We found that the soliton characteristics are strongly dependent on the choice of velocity distribution function through the nonthermal spectral indices r,q, α as well as on the ion and dust temperatures. For (r,q) distributed electrons, we found that the soliton amplitude increases (decreases) with smaller (higher) values of negative (positive) r. For Cairns distributed ions, we found a transition from negative to positive polarity solitary structures with the coexistence in between as the nonthermal parameter α increases. Our results gave a better explanation for the formation of dust acoustic solitary structures (DASS) and their dependence on high and low energy particles in nonthermal distribution profiles in space environments.
Bremsstrahlung emission from nucleon-nucleus reactions in dense medium of compact stars
Authors: Maydanyuk Sergei P. , Xie 谢 Ju-Jun 聚军 , Shaulskyi Kostiantyn A. 
Published: December 2024

Abstract
Bremsstrahlung photons emitted during nucleon-nucleus reactions in compact stars are investigated. The influence of stellar medium density on emission intensity is studied from a quantum perspective for the first time. A bremsstrahlung model is generalized, where a new term describing the influence of the stellar medium is added to interactions between nucleons and nuclei (in the framework of a nuclear model of deformed oscillatoric shells). Polytropic EOS, Chandrasekar EOS, and Harrison-Wheeler EOS are employed for calculation. Haensel and Potekhin's unified EOS of neutron-star matter based on FPS and SLy EOSs are used for tests. Bremsstrahlung calculations are tested on existing measurements of bremsstrahlung in the scattering of protons off 197Au nuclei at a proton beam energy of

MeV. Many properties of bremsstrahlung emitted from nuclear processes in the stellar medium of compact stars are studied for the first time. In particular, the spectra of photons in the scattering of protons and neutrons off 4He, 8Be, 12C, 16O, 24Mg, 40Ca, 56Fe are estimated based on stellar medium density. The medium of white dwarfs has a small influence on the bremsstrahlung emission from nuclear processes, while bremsstrahlung emission is intensive in neutron stars and it is changed in dependence on stellar medium and structure.
Searching Radio Signals from Two Magnetars and a High-magnetic Field Pulsar and the Serendipitous Discovery of a New Radio Pulsar PSR J1935+2200
Authors: Xie Lang , Han J. L. , Yang Z. L. , Jing W. C. , Zhou D. J. , Su W. Q. , Yan Yi , Wang Tao , Cai Nan-Nan , Wang P. F. , Wang Chen 
Published: December 2024

Abstract
Magnetars are slowly rotating, highly magnetized young neutron stars that can show transient radio phenomena for radio pulses and fast radio bursts. We conducted radio observations from two magnetars SGR J1935+2154 and 3XMM J185246.6+003317 and a high-magnetic field pulsar PSR J1846–0258 using the Five-hundred-meter Aperture Spherical radio Telescope (FAST). We performed single pulse and periodicity searches and did not detect radio signals from them. From the piggyback data recorded by other FAST telescope beams when we observed the magnetar SGR 1935+2154, we serendipitously discovered a new radio pulsar, PSR J1935+2200. We carried out the follow-up observations and obtained the timing solution based on these new observations and the archive FAST data. PSR J1935+2200 is an isolated old pulsar, with a spin period of 0.91 s, a spin-period derivative of 9.19 × 10−15 s s−1, and a characteristic age of 1.57 Myr. It is a weak pulsar with a flux density of 9.8 μJy at 1.25 GHz. Discovery of a new pulsar from the long FAST observations of 30 minutes implies that there may be more weak older pulsars in the Galactic disk to be discovered.
Implementing deep learning-based disruption prediction in a drifting data environment of new tokamak: HL-3
Authors: Yang Zongyu , Zhong Wulyu , Xia Fan , Gao Zhe , Zhu Xiaobo , Li Jiyuan , Hu Liwen , Xu Zhaohe , Li Da , Zheng Guohui , Chen Yihang , Zhang Junzhao , Li Bo , Zhang Xiaolong , Zhu Yiren , Tong Ruihai , Dong Yunbo , Zhang Yipo , Yuan Boda , Yu Xin , He Zongyuhui , Tian Wenjing , Gong Xinwen , Xu Min 
Published: December 2024

Abstract
A deep learning-based disruption prediction algorithm has been implemented on a new tokamak, HL-3. An Area Under receiver-operator characteristic Curve of 0.940 has been realized offline over a test campaign involving 72 disruptive and 240 non-disruptive shots, despite the limited training data available from the initial two campaigns. In addition to the well-documented challenge of insufficient training data, a previously unanticipated issue is addressed that the data distribution of a new device is continuously drifting. The plasma scans across a broad parameter space, bringing a drifting distribution of disruption causes and diagnostic data. This problem is often overlooked in previous implementations on steadily operating tokamaks, necessitating greater attention in future tokamaks like ITER. To address these challenges, innovative modules including predict-first neural network, data augmentation, and pseudo data placeholders are developed and implemented, which promotes the accuracy by up to 20%. A series of advantages are also brought by the modules, including the robustness in handling missing input channels, and the interpretability to identify which parameter of plasma is under abnormal condition. The results demonstrate that, with dedicated data collection and algorithm implementation, the issues of limited data and drifting distribution can be overcome, and further, the deep learning-based algorithm can reliably provide disruption alarms on a new tokamak.
Research on Control Technology of Variable Load Gun Pitch Servo System
Authors: Dai Pu , Du Manli , Yang Bo , Cao Yan 
Published: December 2024

Abstract
The artillery pitch servo system has a significant unbalanced torque within its pitch range, which varies greatly with the change of pitch angle. The conventional control method is designed based on the control model of the controlled object. Due to load changes, the control model of the controlled object in the system changes, resulting in poor consistency of control characteristics in different pitch intervals, and even exceeding the dynamic and static performance and system instability in large unbalanced torque pitch intervals. On the basis of analyzing the composition, working principle, and torque variation of the pitch servo system, this article analyzes the problems of conventional control methods and proposes a control method for artillery pitch servo system based on SMVC control. Through MATLAB simulation and experiments, it is shown that this control method can effectively overcome the impact of variable loads on the pitch servo system, significantly improve the dynamic and static performance of the system, and improve the control effect of the system.
Modeling and Simulation Method of Coordinated Manipulator Based on Robotic Toolbox and ADAMS
Authors: Shenggang Wei , Fengjuan Xie , Liguo Hou , Guangning Li 
Published: December 2024

Abstract
The coordinator was an important component of the automatic ammunition loading system of large-caliber artillery. In this paper, kinematics and dynamics of a coordination manipulator with five degrees of freedom were carried out. The forward and inverse kinematics analysis and motion trajectory planning of the simplified coordination manipulator under different firing angles were carried out with Robotic Toolbox to obtain the motion parameters of angular displacement, angular velocity and angular acceleration at each driving joint of the manipulator. Using the motion parameters obtained from the trajectory planning, the inverse dynamics of the manipulator was analyzed by ADAMS, and the driving torque curves of each joint were calculated, which provided a reference for the subsequent prototype development and simulation control of the manipulator.
Optimization design of a dual 5-phase flux-switching permanent-magnet machine for a direct-drive manipulator in artillery automatic loading applications
Authors: Wang Zhe , Tong Minghao , Zhu Jianlong , Chen Longmiao , Xu Zhiyuan , Huangfu Bingbin 
Published: December 2024

Abstract
Due to the increasing demand for high firing speeds in large-caliber artillery, automatic loading systems have become increasingly important. To enhance the reliability of the automatic loading system, a direct-drive rotary manipulator based on a multi-phase outer-rotor flux-switching permanent-magnet machine is proposed. First, the machine topology is designed, including the type, size, rated parameters, and the stator-tooth/rotor-pole combination. Then, aiming to minimize torque ripple and maximize output torque, the optimization procedure is implemented for the proposed machine. The FEA results compare the original and optimized machines. Finally, the structural design of the entire rotary manipulator is presented.
Enhancing Target Tracking Capability in Weapon Systems Using Target Detection and Sensor Network Mechanisms
Authors: Liu Jiancheng , Qi Wanlong , Hou Gang , Lv Mengen , Wang Zhenming 
Published: December 2024

Abstract
The ability to track targets in weapon systems profoundly impacts the precision and potency of target engagement. Stable and accurate target tracking is pivotal for bolstering military capabilities. This study proposes a framework that integrates a target detection probability model with a wireless sensor network mechanism to address challenges in enhancing the reliability of multi-target tracking in weapon systems. We introduce a closed-loop target tracking framework called MTT-SNM, which integrates multiple-source target tracking modules to improve the system’s capability to capture crucial information for target acquisition. Additionally, we devise a position estimation module and a node collaboration module to achieve smooth, continuous future position estimation with higher precision and reduced uncertainty based on current position estimates. This capability aids in guiding coordinated target tracking within the system and enhancing collaborative tracking capabilities. Furthermore, a target recovery module with a four-phase recovery strategy is introduced to swiftly locate targets after loss, thereby enhancing the stability of target tracking in the system. Extensive experimentation validates the outstanding performance of the MTT-SNM framework in system target tracking.
Research on Cooperative Guidance Technology of Small Tactical Air-to-ground Missile
Authors: Yang K , Wang G P , He Y , Peng Y L 
Published: December 2024

Abstract
To explore the feasibility of collaborative guidance for small tactical air-to-ground missiles and enhance their ability to cope with future complex battlefield systems, this article first elaborated on the principle of multi missile collaborative guidance. Then, based on the operational mission of air-to-ground missiles, several collaborative guidance combat modes were proposed. For specific combat modes, time and angle collaborative guidance laws suitable for air-to-ground missiles were designed and developed. Overcoming the problems of short flight time, fast speed and inability to adjust of air-to-ground missiles, and completing mathematical simulation calculations, the results show that this method can effectively solve the problem of coordinated guidance of air-to-ground missiles, achieve simultaneous attack, rapid attack, and multi target attack, and improve the penetration ability, battlefield survival ability, and strike ability of air-to-ground missiles against targets.
Near-Field Target Detection Method for Vortex Electromagnetic Wave Radar based on Modal Baseline
Authors: Sun Jiayue , Liu Junhao , Chen Qian , Fu Chaowei , Zheng Chengxin 
Published: December 2024

Abstract
Vortex electromagnetic (EM) waves can provide more target information, which is orbital angular momentum (OAM), than traditional plane waves in the field of radar detection. By emitting multiple different OAM modes of vortex EM waves to the same target, the azimuth information of the target can be obtained. The Linear Frequency Modulated (LFM) radar is often used in current OAM radar design. At present, researches on vortex EM wave imaging usually requires the emission of a large number of OAM modes to irradiate the target. Although many achievements have been made to significantly reduce this number, it is often accompanied by problems such as loss of azimuth imaging accuracy or poor real-time performance in practical applications. In response to this issue, this paper proposes a near-field target detection method based on modal baseline using vortex EM waves. By alternately emitting vortex EM waves with least OAM mode difference of 1, the method achieves range-velocity imaging while the OAM mode phase information is not blurred. The target detection task is carried out in the range-Doppler dimension, avoiding the problem of azimuth imaging. Through signal processing, our method achieves 3d point cloud detection of target velocity, range, and azimuth. Simulation results compared with traditional phase comparison azimuth measurement method proved the superiority of our method. The work and results provide suggestions to the development of vortex EM wave target detection.
Analysis of the load distribution law and influencing factors of large-load three-stage synchronous ball screw
Authors: Wen Haoxiang , Wang Jinyuan , Zhao Gaoyang , Yao Jianyong , He Xiansong , Yu Xiaochuan 
Published: December 2024

Abstract
Based on the Hertz contact theory, the contact relationship between adjacent balls and lead screw, and the nut raceways is established for a three-stage synchronous ball screw. A model of axial stiffness for the three-stage synchronous ball screw under large load is established. Considering both the axial stiffness of the screw and the deformation of the screw and nut, the distribution of working contact angles and loads of all balls in the three-stage ball screw is established. Taking a three-hinge-point erection mathematical model as an example, a transmission model of the three-stage synchronous ball screw is established, plan the erection trajectory, and analyze and calculate the deformation and force of the balls in the three-stage synchronous ball screw under different load conditions and the force of a single ball in the erection process. The calculation results show that, during the erection process, the load distribution, the radial clearance, the normal deformation between balls and screw and between balls and nut of different balls in each stage of the ball screw are different.
Research on Structural Parameter Design of High Voltage Plane Switch
Authors: Zhou Mi , Li Jiao , Meng Qingying , Wang Yin , Enyi Chu , Lei Jie , Tong Honghai , Diwu Minjie , Yin Guofu 
Published: December 2024

Abstract
In order to determine the structural parameters of the three electrodes of the high-voltage plane switch, the effects of the main electrode gap distance, trigger electrode width, main electrode radius, electrode thickness and other structural parameters on the static breakdown voltage (SBV) of the high-voltage plane switch were obtained by simulation calculation. The optimized structure parameters of the planar switch are obtained, including primary electrode gap 2.0mm, trigger electrode width 1.2mm, trigger electrode in the center of the two main electrodes, and electrode thickness 4 μ m. The performance of the designed high-voltage planar switch is basically consistent with that of the spark gap switch.
Study on Static Explosion Shock Wave Test and Numerical Simulation of Warhead
Authors: Wang Changli , Qian Bingwen , Ke Ming , Zhang Xin , Wu Zhenghao , Li Kang , Zhang Yusong 
Published: December 2024

Abstract
In order to study the distribution law of free field and ground reflection shock wave overpressure in the static explosion test of warhead, based on high-speed photography and image processing technology, the free field shock wave overpressure test at different blast center distance was carried out, and the ground shock wave overpressure test at different blast center distance was carried out with ground shock wave measuring device. The static value simulation of the battle department was performed through the limited element analysis software. The results show that the measurement value of shock wave overpressure will be disturbed by the ballistic wave produced by the fragment passing over the sensor sensitive surface and the vibration of the measuring device. In the free field and ground shock wave tests, the absolute values of the average relative errors of theoretical and measured data are less than 25% and 20% respectively. In the numerical simulation, the absolute values of the average relative errors of the theoretical data of free field and ground shock wave overpressure and the simulation data are less than 16% and 34% respectively, and the absolute values of the average relative errors of the theoretical data of ground shock wave overpressure and the simulation data are less than 25% and 18% respectively. The shock wave overpressure values obtained by test and numerical simulation show that at the same detonation center distance, the ground and free field shock wave overpressure values increase with the increase of the warhead loading ratio, and the closer the distance to the detonation center, the more obvious the increase of shock wave overpressure value with the increase of the loading ratio.
Experimental and simulation of polyurea/CFRP composite structures were studied under high speed impact of projectile
Authors: Liu Q , Chen P W , Zhai H B , Xiao Y 
Published: December 2024

Abstract
With the development of composite structures, polyurea materials can be used to improve the protective performance of multilayer composite structures subjected to explosion or impact. In order to study the penetration resistance of polyurea sprayed CFRP composites, the fragment penetration loading test was carried out with a 14.5mm ballistic gun. The influence of polyurea coating position on the dynamic response of polyurea/CFRP composite structures were analyzed and discussed by test and numerical simulation. The results showed that polyurea coating on the back surface of CFRP can reduce the damage of CFRP and reduce the residual velocity of fragments compared with bare CFRP. The numerical simulation results were in good agreement with the experimental results, which showed that the numerical method can accurately simulate the penetration of fragment into polyurea/CFRP composites structure. The simulation results showed that the energy absorption of polyurea was increased as polyurea was sprayed on the back of CFRP. The lower the fragment initial velocity, the greater the contribution of polyurea for improving the penetration resistance of structure. The large tensile deformation and damage of fiber under the process of penetration can be seen by numerical simulation, revealing that the anti-ballistic mechanism of polyurea.
Study on the Influence of Composite Charge Structure Parameters on Detonation Wavefront
Authors: Lichen Zhao , Jianping Yin , Xudong Li , Jianya Yi 
Published: December 2024

Abstract
In order to study the detonation wave propagation process of the composite charge, the wavefront type, and the relationship between the characteristic parameter α of the composite charge wavefront and the detonation velocity difference of the inner and outer layer explosive. The finite element software was used to numerically simulate and calculate six structural schemes that changed the detonation velocity of the inner and outer layers explosive of the composite charge and the diameter ratio of the inner and outer explosives. The test results show that the composite charge structure with different inner and outer explosive detonation velocities and the diameter ratio of inner and outer explosives has different wavefront propagation processes and wavefront types. When the diameter ratio of the inner and outer explosives in the composite charge structure is the same, the detonation velocity difference between the inner and outer layers of explosives is changed, and the influence law of the incident Angle changes with the change of the detonation velocity difference is found.
Fast calculation method for implosion loads in cylindrical vessels under single explosion source
Authors: Chen G J , Qiu J L , Zhang Y M , Wang S Y 
Published: December 2024

Abstract
Combined with the image explosion source method and LAMBR (LAMB revisied) model, a fast calculation method of wall load of implosion in cylindrical vessels with single explosion source was proposed. The verification results show that the maximum relative errors of the predicted and simulated values of overpressure peak and specific impulse on the structural wall are −13.66% and −17.84% respectively. The predicted overpressure and specific impulse time curves are in good agreement with that obtained by simulation, which can reflect the multimodality of the load at the measuring point under the action of implosion and verify the effectiveness of the method.
Microscopic scale simulation study on the orientation degree of heterocyclic aramid fibers
Authors: Gao Yingying , Li Shuhu , Xu Jingli , Wang Ronghui , Wang Danyong , Zhang Haiyun , Guo Jianfen 
Published: December 2024

Abstract
Heterocyclic aramid fibers have more outstanding heat resistance and higher mechanical properties than pure aramid fibers (without heterocycles). Aromatic copolyamide fibers containing heterocycles are widely used in aviation, aerospace, armor protection, bulletproof vests, and space development due to their outstanding excellent properties. Fiber orientation has a significant impact on the mechanical and physical properties of products. However, the research on micro simulation calculation of fiber orientation is limited to qualitative comparison between different orientation degrees, and cannot quantitatively obtain the value of orientation degree. Therefore, this article mainly studies a new method for micro calculation of orientation degree, and simulates the influence of orientation degree and molecular weight on the Young’s modulus of fibers at the micro scale.
Analysis of the influence of structural parameters of irregular charges on the forming performance of EFP with tail Fins
Authors: Ronghua Ma , Wenbin Li , Peng Chen , Dacheng Gao , Chuanyun Tao , Zhenchao Liang 
Published: December 2024

Abstract
In this study, a special charge structure is designed to form an explosively formed projectile (EFP) with fins for stable flight. By using LS-DYNA for numerical simulation, the influence of charge structure parameters on the EFP characteristics of the tail fins was analyzed. The results show that the irregular charge structure can reliably form an EFP with fins, and the number of EFP tail fins can be controlled by changing the number of sides n of the regular polygon at the top section of the charge. Changing the shape parameters n and Dn of the top section of the charge will greatly affect the shape of the tail fins, while the charge height H has a significant impact on the length to diameter ratio of EFP, the appropriate range of H values should be between 0.5Dc and 0.8Dc. The research results can provide reference for the design ideas of tail wing EFP.