bluuebunny/crossref_metadata_2025_split huggingface dataset:
Improving the efficiency of ZnO/WS2/CZTS1 solar cells using CZTS2 as BSF layer by SCAPS-1D numerical simulation
Authors: Dakua Pratap Kumar , Panda Deepak Kumar 
Published: June 2023

Abstract
With a high absorption coefficient and tunable bandgap CZTS (Copper Zinc Tin Sulfide) makes it suitable for photovoltaic applications. Present paper deals with the simulation and modeling of CZTS-based solar cells using tungsten disulfide (WS2) as the buffer layer and CZTS2 as the back surface field (BSF) layer to study the performance of the solar cell. Considering different physical and geometrical parameters such as thickness, acceptor density, interfacial defect density, and metal contact work functions the device calibration has been done. The temperature is varied from 300 K to 400 K to study the impact on device performance. The C-V and 1/C2 plot is presented to calculate the built-in voltage for the device. The series (Rs) and shunt (Rsh) resistance of 1 and 106 ohm.cm2 were kept throughout the simulation. The optimized thickness for the absorber, BSF, buffer, and window layers are 800 nm, 140 nm, 30 nm, and 90 nm respectively. The obtained results are validated using the experimental results available in the literature. Varying the values of different parameters, the optimal efficiency of 26% was reported in this work. Contrary to conventional solar cells, which contain expensive and toxic elements, WS2 may be a good option as a buffer layer in CZTS solar cells.
Plus-shaped dielectric grating for seven-channel transmission
Authors: Zhou Yongchun , Wang Bo 
Published: June 2023

Abstract
A new seven-channel transmission grating with plus-shaped array under normal incidence is proposed and discussed in this paper. Through the simulated annealing (SA) algorithm and rigorous coupled-wave analysis (RCWA), the novel microstructure can split the incident energy into 0-th/±1-st/±2-nd/±3-rd orders evenly. The influence of incident angle, period, incident wavelength, and other parameters on the diffraction efficiency are also analyzed in this paper. For transverse magnetic (TM) polarization, the range of period is 3062–3246 nm and the bandwidth of incident angle and wavelength is 1.96° and 32.3 nm, respectively. It can be concluded that the TM-polarized light of the designed grating has a good performance in incident bandwidth and fabrication tolerance. In addition, the efficiency of transverse electric (TE) polarization has the satisfactory uniformity of 2.40%. Therefore, the proposed grating has a certain significance for the research of multi-port beam splitter, especially for the seven-channel polarization-independent beam splitter.
A path to precision cosmology: synergy between four promising late-universe cosmological probes
Authors: Wu Peng-Ju , Shao Yue , Jin Shang-Jie , Zhang Xin 
Published: June 2023

Abstract
In the next decades, it is necessary to forge new late-universe cosmological probes to precisely measure the Hubble constant and the equation of state of dark energy simultaneously. In this work, we show that the four novel late-universe cosmological probes, 21 cm intensity mapping (IM), fast radio burst (FRB), gravitational wave (GW) standard siren, and strong gravitational lensing (SGL), are expected to be forged into useful tools in solving the Hubble tension and exploring dark energy. We propose that the synergy of them is rather important in cosmology. We simulate the 21 cm IM, FRB, GW, and SGL data based on the hypothetical observations of the Hydrogen Intensity and Real-time Analysis eXperiment, the Square Kilometre Array, the Einstein Telescope, and the Large Synoptic Survey Telescope, respectively. We find that the four probes have different parameter dependencies in cosmological constraints, so any combination of them can break the degeneracies and thus significantly improve the constraint precision. The joint 21 cm IM+FRB+GW+SGL data can provide the constraint errors of σ(Ωm) = 0.0022 and σ(H
0) = 0.16 km s-1 Mpc-1 in the ΛCDM model, which meet the standard of precision cosmology, i.e., the constraint precision of parameters is better than 1%. In addition, the joint data give σ(w) = 0.020 in the wCDM model, and σ(w
0) = 0.066 and σ(wa
) = 0.25 in the w
0
wa
CDM model, which are better than the constraints obtained by the CMB+BAO+SN data. We show that the synergy between the four late-universe cosmological probes has magnificent prospects.
Hypersonic target interception based on short-range damage estimation
Authors: Wang Y Z , Chen K 
Published: June 2023

Abstract
Aiming at the interception problem of hypersonic target end phase, the flight interception simulation based on semi-active radar guidance is firstly established, and a warhead based on fragment damage is designed. Secondly, research proposes an effective method of target damage and verifies the interception effect by simulation. AUTODYN was used to establish the 3D finite element model based on the nonlinear flight dynamics model, to simulate the damage process and fragmentation dispersion. In this paper, the probability of success of missile interception is estimated by using conditional probability and the distribution of fragment field combined with the miss distance in the interception process and the fragment explosive dispersion law of the steel ball, so as to ensure the destruction of the terminal hypersonic incoming weapon within the safe range.
Simulation Environment of Unmanned Group Reconnaissance System Based on RVIZ and GYM
Authors: Weidong Huang , Fulun Peng , Jie Liu , Peng He , Yuan Qi , Bing Yang 
Published: June 2023

Abstract
This paper studies the simulation environment of the current cluster unmanned system, analyzes the shortcomings of the cluster unmanned system, and designs a cluster robot simulation system based on RVIZ and GYM, which has both the fast training algorithm and the physical attributes of the simulation environment, and uses DDS to transmit robot control instructions and state information. After the GYM fast training algorithm, Control the cluster robots to verify the algorithm and collect the state information of the robots in the physical simulation environment of RVIZ. After the whole simulation is passed, the algorithm can be directly used for the path planning of cluster robots. The results show that the simulation environment can effectively simulate the unmanned group reconnaissance system.
Research on Adaptive Flexible Wing with Variable Trailing Edge
Authors: Li Kang , Ba Weitao , Liu Yang , Lv ShuiYan , Yang Yang , Xie LinQing 
Published: June 2023

Abstract
The trailing edge deformable wing is one of the main development directions of future aircraft design. The technology of active camber of wing trailing edge can significantly improve the aerodynamic performance of aircraft. In this paper, the motor drives the parabolic crankshaft and the distributed crankshaft drives the flexible skin of the trailing edge of the wing, which can realize the deflection of the trailing edge of the wing at a large angle of 0~30 degrees. At the same time, the surface of the wing is continuous and smooth. Moreover, the aerodynamic simulation results of the deformed wing show that the trailing edge deflection is beneficial to increase the lift. It can increase the maximum lift coefficient by 2 times and the maximum lift drag ratio by 18%. Adaptive flexible wing technology is applied to rocket sleds with side wings. This technology can increase the downward pressure of the side wing of the rocket block and improve the operation safety.
A fast calculation model for interior ballistics simulation of a recoilless launch system with high chamber pressure
Authors: Xie Wenkui , Sun Yuxin 
Published: June 2023

Abstract
Recoilless launch system is economical and convenient. This paper provided a recoilless launch system with high chamber pressure based on the theory of recoilless gun. A program for interior ballistics simulation of the launch system based on the mixed propellent was designed. The curves of chamber pressure and projectile velocity on time and projectile travels were provided by the program. And the phenomena of different combustion stages presented by the curve are discussed. The simulation results reached the set indicators, and it was consistent with the actual interior ballistics. The designed model has certain reference value for real-time simulation and fast computation.
Study on Damage Effectiveness of Single Projectile of Small Caliber Anti-aircraft Gun Under Multi-error Constraints
Authors: He B , Ren J , Jiang Z J , Fan X , Tang C F , Li X Z , Yang T Q , Feng H Z 
Published: June 2023

Abstract
In this paper, the damage effectiveness of a single projectile of small caliber (30-35 mm) anti-aircraft gun under multi-error constraints is studied. Based on the known prior information of target motion and the dispersion mathematical model of prefabricated fragment warhead, under the constraints of fragment effective killing radius and target equivalent size, the fuze starting characteristic factor is introduced to establish the integrated model of fuze and warhead. Based on the Monte-Carlo method, the variation law of the damage effectiveness of a single projectile under the joint constraints of the gun firing angle error and the fuze fixed range error is analyzed. The simulated annealing (SA) algorithm is used to find the global optimal solution of the model. The optimal damage effectiveness of a single projectile under multi-error constraints is found. The results show that the damage effectiveness of single projectile is increased by 26.91% without changing the state of existing weapon and equipment.
Experimental investigation of ethylene-fueled ramjet rotating detonation engine with an annular combustor
Authors: Feng Wenkang , Zheng Quan , Xiao Qiang , Han Xinpei , Cao Qi , Huang Hanli , Wu Bowen , Weng Chunsheng 
Published: June 2023

Abstract
A ramjet-mode rotating detonation engine fueled by ethylene is designed to demonstrate the feasibility of rotating detonation organization in annular combustor under high-speed incoming flow condition. The incoming flow with the design total temperature of 860 K and Mach number of 2 at the isolator inlet is provided by an air-heater, and the total mass flow is about 1.0 kg/s. The results show that the ramjet rotating detonation engine can operate in detonation mode when the equivalence ratio (ER) is no less than 0.54. By high-frequency pressure analysis and optical observation, two propagation modes of detonation wave are observed: rotating detonation in the ER range of 0.54-0.71 and longitudinally pulsating detonation in the ER range of 0.82-0.97. In rotating detonation mode, the wave velocity increases as ER increases, and the detonation velocities are about 60% of the CJ value. In longitudinally pulsating detonation mode, the propagation frequencies of the detonation wave are in the range of 1010 Hz-1017 Hz, which is much lower than that in rotating detonation mode, and the upstream propagation velocity of the detonation wave is estimated as 964 m/s. In addition, the maximum static pressure in the combustor increases with the ER from 0.54 to 0.97, and reaches 0.24 MPa when ER is 0.97. When ER is no more than 0.58, the isolator can effectively suppress the back pressure in the combustor, while ER is no less than 0.71, the back pressure in the combustor affects the flow at the isolator inlet, which implies that the isolator design needs to be optimized.
Attitude Measuring for Spinning Air Vehicle Based on Kinematics
Authors: Xiaojuan Huang , Yaojun Li , Weigang Zhang , Kang Li 
Published: June 2023

Abstract
The attitude measurement method of satellite navigation for spinning air vehicles is innovatively proposed. As an attitude measurement backup solution for inertial navigation system or magnetometer, based on kinematics principle, the velocity vector from GNSS receiver could be used to measure attitude for spinning air vehicles without any other sensors. The three-dimensional pseudo-attitude kinematics modelling is realized under the condition that the flight angle of attack and sideslip angle are small; the pseudo-attitude is transformed into inertial coordinates through Euler attitude matrix, and its accuracy index meets the actual working requirements.
Design of Guidance Law for Smart Missile Based on Direct Mode Configuration with Implicit Dynamic-Inverse
Authors: Yefei Yin , Xu Li , Qiaoqi Li 
Published: June 2023

Abstract
The design of guidance law for smart missile based on implicit dynamic-inverse direct mode configuration is described in this paper. The dynamic-inverse theory and direct mode algorithm are applied to the design of guidance law. The pitching acceleration and yaw acceleration are designed for the pitch channel by using the augmented proportional guidance and for the yaw channel by using the dynamic-inverse theory respectively. The attacking time parameter and the attack time error equation are introduced as the constraint criteria for the design of the dynamic-inverse. According to the singular perturbation theory, the fast and slow subsystems are designed by dynamic-inverse control, and then the required control quantities are obtained by solving the relative motion equations of the missile and the target. The simulation results showed that the guidance law can fully meet the guidance trajectory performance requirements of the smart missile.
The study on the preparation of ultra-low thermal expansion ceramic with high elastic modulus
Authors: Zhang C , Liu F F , Guo J B , Guo Z Z , Guo M , Yang S Y , Xu C Y , Sun M Y , Xu H , Fang S J 
Published: June 2023

Abstract
The paper studied the synthesis of cordierite powders and the preparation of ultra-low thermal expansion ceramic with high elastic modulus. The powder was synthesized by solid state reaction using MgO, Al2O3 and SiO2 as raw materials. The effect of temperature on powder purity, phase and properties of ceramic was mainly studied. The results show that the cordierite powder with higher purity and reactivity was synthesized at 1390°C, containing two kinds of phase (α-cordierite and β-cordierite). The compact cordierite ceramic could be obtained at 1420°C with homogeneous and compact organizations, besides, this sample had a wide operating temperature area with low thermal expansion, and the higher elastic modulus.
Error Comparison of CNFFFT and Hankel Method in RCS Near-Field to Far-Field Transformation
Authors: Zhao Peng , Hu Weidong , Liu Yang , Yao Zhiyu , Sun Jianhang 
Published: June 2023

Abstract
At present, there are mainly two kinds of image-based near-field to far-field transformation (NFFFT) algorithms: Hankel method and circular near-field-to-far-field transformation (CNFFFT). Due to the approximation in the measurement distance, the accuracy of Hankel method is lower than that of CNFFFT. However, the implementation of CNFFFT is complex and time-consuming. It is necessary to determine the detailed relationship between the transformation error and the near-field test distance for both algorithms to provide a basis for the choice of which algorithm to use. In this paper, the effect of the near-field test distance approximation of the two algorithms is obtained by simulating 4, 5, and 9 scattering point models. Meanwhile, an accurate comparison method for two NFFFT algorithms under different test distances is proposed.
Research on Architecture Modeling of Aviation-guided Munitions System Based on MBSE
Authors: Wang Jiuhe , Ma Xiaodong , He Xiaofu , Hu Lifeng 
Published: June 2023

Abstract
In order to explore the forward R & D mode of aviation-guided munitions, an architecture modeling method of aviation-guided munitions weapon system based on MBSE(Model Based System Engineering) is proposed. Based on MBSE typical methodology and SysML language, taking a certain type of aviation-guided munition as an example, the system architecture model is constructed, and the design process including the requirements analysis, functional logic analysis, architecture balance and analysis, and scheme detailed design of aviation-guided munitions is described. The simulation analysis and verification are carried out, and the complete description of the continuous dynamic behavior of the aviation-guided munitions system architecture is realized. The research results can provide support for the scheme design and agile research and development of aviation-guided munitions equipment.
Numerical Study of Shock Wave Boundary Layer Interaction Based on an Anisotropic Turbulence Model
Authors: Hao Chunhui , Yan Wenhui , Zhou Junwei 
Published: June 2023

Abstract
This paper presents numerical simulations of incident oblique shock wave impinging on a flat plate with a turbulent boundary layer using a nonlinear anisotropic turbulence model. Three cases with different incident shock angles under the same free-stream Mach number are studied, including attachment flow, incipient separation flow and outstanding separation flows. Convection terms and diffusion terms are calculated using the third-order Roe’s flux difference splitting scheme and the second-order central difference scheme in the code, respectively. The Runge-Kutta time marching method is employed to solve the governing equations for steady state solutions. Comparisons between the simulated results and experimental data are carried out, which include density contours, pressure distribution, skin friction coefficients distribution and streamline vectors. To capture the essential behavior of this complex anisotropic turbulence separation flow caused by the shock-wave-boundary-layer-interaction (SWBLI), an anisotropic eddy viscosity tensor and a nonlinear Reynolds stress-strain constitutive relationship are used in this model. The anisotropic eddy viscosity tensor is composed of turbulent fluctuation velocity vector and characteristic length vector which are obtained by statistical partial average scheme. With proper modeling of anisotropic eddy viscosity tensor, the numerical results are in good agreement with the experimental data. It is worthy to point it out that the computation accuracy decreases with increasing interaction intensity.
Effects of Stage Spacing on Contra-Rotating Propeller Aerodynamic Interactions
Authors: Wenhui Yan , Kun Zhang 
Published: June 2023

Abstract
To identify the law of aerodynamic interactions of contra-rotating propellers (CRPs) and improve their aerodynamics, this study investigates the aerodynamic interactions of 4 CRPs (six blades in front and six in back) with different stage spacings using the Reynolds-averaged Navier-Stokes (RANS) equations-based method. The results showed that the CRP whose stage spacing was 0.25 times the propeller diameter delivered the highest average efficiency and that the aerodynamic interactions between the front and rear propellers decreased as the spacing widened, and compared with the rear propeller, the front one was more sensitive to stage spacing due to the aerodynamic interaction-generated thrust fluctuations. It can be seen that stage spacing exerts a significant effect on CRP aerodynamic interactions. Therefore, choosing an appropriate stage spacing in CRP design is of great significance to enhance its aerodynamics.
Simulation analysis of dynamical performance and economic performance for the electric vehicle
Authors: Pan Jiang-li , Yang Xu , Zou Bo , Lv Bu , Liu Zun-fei , Zhang Wen-juan , Ye Shuang-ping , Feng-Min  
Published: June 2023

Abstract
Aimming at the problem that it is difficult to evaluate whether the dynamical performance and economic performance meet the expected indicators after selecting powertrain for the special vehicle, a vehicle simulation model was built based on the vehicle dynamics theory for the simulation analysis of dynamical performanc and economic performance. The maximum speed, acceleration time, maximum climbing slope and the biggest continue voyage course were obtained by simulating. The simulation results show that its dynamical performance and economic performance meet the expected targets, and the vehicle simulation model has high accuracy and short modeling cycle, which can provide reference for the development of the electric vehicle.
Interface failure analysis of coating in gun barrel under thermal-pressure coupling effect
Authors: Geng Xuehao , Liu Feifei , Gan Jinjie , Si Zhihui , Zhang Rui 
Published: June 2023

Abstract
This paper is devoted to research the interface failure mechanism of coating in gun barrel, three interface failure models (interface shear failure, interface bending failure and interface crack growth failure) of coating in gun barrel are built with consideration of thermal-pressure coupling effect, and the failure criterion is given. The critical failure length/thickness ratio of coating segments for different failure models during firing process are calculated based on temperature field simulation result, then by comparison of the calculation results, the main interface failure way of coating in gun barrel is confirmed.
Overall Structural Design of a Radar with 2-D Arrayed Independent Conjugate Sealed Air Ducts Under Strong Electromagnetic Radiation
Authors: Wang Yuhan , Li Zhi , Fang Yiqi , Bai Yajie 
Published: June 2023

Abstract
An overall radar structure with 2-D arrayed independent conjugate sealed air ducts is discussed. It can operate well in a strong electromagnetic radiation environment. Completely sealed, the case consists of two installation cavities. The front cavity achieves wave transmission and reception and lessens electromagnetic radiation from large power microwave weapons, making it possible for the radar’s transmitting and receiving waves to pass with low attenuation. The horizontal air duct in the front cavity dissipates heat of the antennae, ensuring the conformity of the direction figure formed by the transmitting chips. The two-sided surface-mount technology applied in the vertical air duct in the back cavity lowers the utilization space and thickness of the radar while raising the dissipation efficiency.
Research on Theoretical Model of Ceramic/PE Composite Protection for Projectile
Authors: Zhang Tianlong , Dong Fangdong , Ma Xuejiao , Liu Zide , Yu Pan 
Published: June 2023

Abstract
In order to predict the ballistic limit of ceramic/ UHMWPE composite protection, a theoretical model of ceramic/UHMWPE composite protection for projectile was established based on A-T model and fiber energy dissipation model. In the ballistic impact process, the fragments will experience ceramic dwell, ceramic fragmentation and fiber layer energy dissipation. The theoretical model obtained is compared with the experimental and simulation results. The results show that the residual velocity obtained by the theoretical model is in good agreement with the experimental and simulation results, and it can be applied to ceramic/UHMWPE composite protection of projectile penetration to a certain extent.
Experimental study on energy release effect of reactive bullet impacting soil simulated target
Authors: Cui H L , Jia Z J , Hu X B , Ren X H , Liu Y 
Published: June 2023

Abstract
To study the energy release of PTFE-Al reactive material bullets penetrating soil target, by firing the bullet with a 12.7mm ballistic gun, and using a high-speed camera to record the energy release process when impacting a simulated target, a nylon 6 plate with 5mm thickness, which has an approximate wave impedance to soil target. The result shows that when the velocity of the bullet is at 553m/s, a flame extinguishes immediately after the PTFE-Al is evoked but could not continue. With the increase of impact velocity, the secondary energy release reaction with greater strength can be realized after the first energy release of the reactive material is excited and maintained for a certain period. It is concluded that the critical velocity of the PTFE-Al reactive material impacting the soil is about 553m/s, and the energy release effect becomes more severe with the increase of impact velocity.