bluuebunny/crossref_metadata_2025_split huggingface dataset:
Guidance algorithm for reusable launch vehicle considering change in target
Authors: Huang Xinyu , Dai Jing , Liu Gang 
Published: May 2024

Abstract
To address the design challenges of reentry guidance for high-speed aircraft in complex environments, and in response to the need for target adjustments during reentry, a method for designing reentry guidance laws with extended range has been introduced. The longitudinal guidance law has significantly improved real-time performance by converting infinite-dimensional optimization into a single-parameter search using the reentry flight corridor approach. The lateral guidance law employs line-of-sight angular deviation corridors to achieve target tracking, while the extended-range guidance law rapidly increases the flight distance of the reusable launch vehicle during the flight by optimizing attack angle profiles. Numerical simulations have been conducted to validate the effectiveness of the longitudinal, lateral, and extended-range guidance laws, indicating that they can meet the mission requirements for target adjustments during reentry.
Reentry trajectory optimization of hypersonic glide vehicle based on improved particle swarm algorithm
Authors: Su Zili , Zhao Jisong , Liu Jiaolong 
Published: May 2024

Abstract
The reentry process of hypersonic glide vehicle presents a host of intricate constraint issues. A method for optimizing the reentry trajectory of hypersonic glide vehicle is presented to achieve the shortest possible reentry time. The approach utilizes the improved particle swarm optimization (IPSO) algorithm. Firstly, population initialization is performed using the quasi-oppositional differential evolution (QODE) strategy to promote diversity within the population. Then an adaptive adjustment algorithm is designed for the inertia weight coefficient and learning factor to achieve a balance between global and local search capabilities. Finally, utilizing the IPSO algorithm for optimizing the flight parameters of the reentry trajectory, the reentry time is reduced from 338 seconds to 335 seconds. The simulations results indicate that the IPSO algorithm outperforms both the standard PSO algorithm and genetic algorithm (GA) in terms of optimization performance index.
Investigation on the growth behaviour of creep crack in 2219 aluminium alloy by nanometre computed tomography
Authors: Fu Kang , Zuo Xin , Zheng Ying , Shi Jianghuan , Guo Qi , Tang Shengming 
Published: May 2024

Abstract
Aluminium alloy is widely utilized in aerospace engineering because of its lightweight and high specific strength. Creep and fracture of aluminium alloy serving at high-temperature conditions are always a long-term concern. Especially creep crack nucleation and growth behaviours under high out-of-plane constraint levels are the significant processes to generate failure. High-resolution nanometre computed tomography equipment can be adopted for obtaining the three-dimensional morphology and information on damage to investigate the mechanism of creep crack growth. According to the obtained results, the stress-field strength has an impact on creep crack propagation under high out-of-plane constraint levels.
Air tightness detection method in parallel for aerospace: mechanical design, system modeling and optimum control
Authors: Yang Bo , Yuan Jianhui , Wang Xiaoliang , Zhang Jianwei , Wu Wei , Xie Mingyang 
Published: May 2024

Abstract
To address the problems of high cost, complex operation, and low efficiency of existing equipment for aerospace, a simple but efficient multichannel air tightness detection device is designed. A physical system model is constructed for the process of inflation, deflation, and inflation with leakage. The expression between the inflation/deflation rate and the valve area is obtained. Through modeling the intersection and rotation of spatial curves, the relationship between the valve area and the valve core angle is derived, and the optimal valve core angle calculation method is proposed to achieve precise rate control of inflation and deflation. Simulation experiments and numerical analysis demonstrate the superiority of the proposed system scheme, the effectiveness of the control method, as well as the accuracy of the mathematical model. For the tested object of 0.3 L, the target pressure of 400 KPa, and the inflation and deflation rate of 75 Kpa/min, by using four channels with a 10 s interval for sequential operation and adjusting valves every 60 s, the efficiency of inflation and deflation is more than 3.5 times that of a single device with a single circuit. Its performance is not much different from real-time automatic control equipment, but the economy is greatly improved.
Analysis of internal pressure and vibration of a flexible expansion ratio elongation nozzle shape
Authors: Zeng Yi , Huang Wei , Xu Jingsheng , Guo Zongtao , Ren Xiaobin 
Published: May 2024

Abstract
The nozzle made of flexible materials can expand and elongate its profile at different flight altitudes, greatly improving the engine’s endurance and ballistic accuracy. However, this also introduces the problem of structural vibration in the nozzle, which adversely affects engine performance. This paper introduces a high-precision hyperelastic material constitutive model for the flexible elongation nozzle and uses numerical simulation to conduct a detailed analysis of the internal pressure and structural vibration under aerodynamic pressure loads. As the flight altitude increases, the pressure magnitude and distribution on the inner wall of the same elongated flexible expansion section do not change. The pressure distribution on the inner wall of the flexible elongation expansion section exhibits certain nonlinear characteristics, and its magnitude decreases gradually along the axial position. The vibration of the elongated expansion nozzle profile becomes more intense with the increase in flight altitude. At high characteristic flight altitudes, the elongation length of the longer expansion section approaches an undamped vibration state.
Orbital constraints and efficiency modeling for calibration satellites in long-range radar applications
Authors: Sun Changjun , Li Yaoyao , Dong Ping 
Published: May 2024

Abstract
Orbit design is a critical aspect of the calibration satellite system, with its effective configuration being integral for successful satellite calibration. This paper addresses the challenge of designing satellite orbits while considering the constraints imposed by satellite-ground equipment performance and launch capabilities. Key factors constraining calibration satellite orbits are analyzed, and orbital constraint equations are developed, focusing on radar performance, calibration time, and regional coverage. The study also introduces a model to assess the efficiency of satellite orbits for calibration purposes, which is rigorously validated through simulation. This study uniquely addresses the integration of radar performance with satellite orbit design, an area not extensively explored in current literature.
Preliminary results for platform testing of ASO-S satellite
Authors: Zhu Cheng , Yin Zengshan , Deng Lei , Bao Haichao , Cao Caixia , Jiang Hu , Chen Binglong , Zhang Ye , Li Xinyu , Liu Kuo , Yang Zhongguang , Yang Yong , He Tao , Bai Yanping , Xu Yibo , Zhu Yunfei , Wang Shouliang 
Published: May 2024

Abstract
Advanced space-based solar observatory, which is short for ASO-S, was successfully launched by Chinese launcher CZ-2D in Oct. 2022. As of Dec. 13, 2022, the platform testing of the ASO-S satellite finished. The platform consists of seven main subsystems. The nominal specifications for every subsystem are laid out in detail in its technical document. The nominal specifications are used as a baseline to judge whether the in-orbit testing results are acceptable. The preliminary results include measurements for every specification for platform testing of the ASO-S satellite. The data analyses have shown that the performance of the main subsystems of the platform has Satisfied the specifications required by the technical documents. The platform performance has been demonstrated to be completely acceptable. The healthy platform performance of ASO-S will further support the payloads of the satellite in carrying out in-orbit observations of Solar activities.
Research on electronics hardening technology of integrated electronic system of lunar exploration Cubesat
Authors: Wu Tao , Zhang Wen , Zhou Yang , Wang Chong , Ao Liang , Cao Suzhi 
Published: May 2024

Abstract
In the lunar exploration CubeSat mission, the complex space environment and limited onboard resources place higher requirements on the anti-radiation design of the integrated electronic system. By analyzing the destructive effects of the deep space radiation environment and the failure mechanism of components, a hardening scheme for the integrated electronic system of lunar exploration CubeSat is proposed. A variety of measures are taken to target the key components and circuit parts in the integrated electronic system that are susceptible to radiation damage. A prototype verification system for anti-radiation hardening technology was designed and system-level testing was carried out. Research results show that adopting effective radiation-resistant hardening technology can significantly improve the safety and reliability of CubeSat integrated electronic systems in deep space environments.
High time effective detection strategy for geosynchronous orbital space debris
Authors: Zhang Hongbo , Wang Ke , Shang Xiaoyu 
Published: May 2024

Abstract
After the formation of a multi-satellite network in a hypersynchronous orbit, it has the ability to continuously and in real-time observe the GEO band, which is an ideal way to solve blind spots and semi-backlight observations and improve the system’s high time-effective coverage ability. In response to the application limitations of high-orbit real-time monitoring constellations in hypersynchronous orbits, such as the large number of satellites in the network, high requirements for satellite detection capability, large field of view, and high launch and orbit cost, this paper proposes a constellation system efficiency analysis method that comprehensively covers both time and space dimensions. Based on this, optimization analysis of satellite detection capability, detection field of view, number of satellites, and orbit height is carried out. Finally, three constellation optimization schemes are provided, which are a semi-major axis of 60000 km with seven satellites, a semi-major axis of 55000 km with eight satellites, and a semi-major axis of 50000 km with ten satellites. The three constellation optimization schemes can provide a reference for the development of space-based high-orbit situational awareness in the future.
Intelligent mission planning of sky survey based on the NSGA-III algorithm
Authors: Jia Rongsheng , Wang Hongfei 
Published: May 2024

Abstract
In recent years, China has been scheduled to launch an all-sky survey telescope for celestial observation. The meticulous arrangement of observation sequences for this telescope is of paramount importance, given the myriad challenges and constraints inherent to such astronomical survey missions. These challenges encompass factors such as spatial limitations, stray light contamination, as well as constraints related to data storage and energy consumption. This undertaking presents a quintessential NP-hard optimization problem. To address this complexity and enhance in-orbit observation efficiency, this study closely adheres to practical engineering considerations. A comprehensive evaluation of diverse constraints is conducted, culminating in the establishment of an optimization model for systematic planning of sky survey missions. The primary optimization objectives encompass maximizing in-orbit observation duration, augmenting the count of observable celestial points, and minimizing maneuvering angles. To tackle this multifaceted problem, a mission planning algorithm is devised based on NSGA-III, a multi-objective optimization technique. The experimental results indicate that the sky survey planning algorithm proposed in this paper can effectively accomplish sky survey observation tasks, achieving the scientific objective of no fewer than 350 daily observation points. It holds the potential to provide algorithmic support for the sky survey telescope mission on the Chinese space station.
A GNU radio-based design for GPS software simulation source
Authors: Lin Yang , Yuan Jiangnan , Wang Guangyi , Shen Mingliang 
Published: May 2024

Abstract
GPS (Global Positioning System) plays a crucial role in modern navigation and positioning applications. Traditional research and development of GPS signals require expensive hardware equipment, limiting the flexibility and scalability of the system. In this paper, an open-source software called GNU Radio is utilized to construct a GPS signal simulation system, leveraging its rich modules and signal processing libraries. The GPS baseband signals are generated using signal processing modules provided by GNU Radio. Appropriate noise and interference are added to simulate the signal characteristics in real-world environments. Both single-channel and multi-channel signal models are presented. By comparing the generated GPS signals with those from hardware-based simulators, the results demonstrate that the GPS software simulator based on GNU Radio can produce high-quality GPS signals with excellent flexibility and adjustability.
Analysis of the mechanical response of solid rocket engine propellant under acceleration shock
Authors: Shangguan Zihan , Zheng Jian , Sun Liangcheng 
Published: May 2024

Abstract
The increased-range solid rocket engine of new ammunition often needs to withstand extremely high acceleration overload, leading to damage to the propellant’s structural integrity. To address this issue, this paper constructs a nonlinear viscoelastic constitutive model for the CMDB propellant by using low- and high-strain rate mechanical property tests. Combined with the secondary development of explicit dynamics and numerical simulation technology, the mechanical response of a certain type of solid rocket propellant under different acceleration impacts is analyzed. The results show that under acceleration impact loads, the propellant will compress, rebound, and recover over time, continuously cycling. Its axial displacement, maximum equivalent stress, and maximum equivalent strain exhibit irregular sinusoidal wave-like periodic cycles. Looking at the time when the peaks appear, the time when the maximum equivalent stress appears always lags behind the time when the maximum axial displacement peak appears. Due to the viscous effect of the viscoelastic material of the propellant, the time when the equivalent strain peak appears will lag behind the equivalent stress. Because of the material’s damping effect, both the peak values of the maximum equivalent stress and equivalent strain decrease over time. Under continuous high acceleration impact loads, this viscous damping phenomenon continuously diminishes, and the peak value of the propellant’s axial displacement gradually increases.
The effect of the stress equilibrium factor on the composite case of the solid rocket motor
Authors: Li Jing , Zhou Changsheng 
Published: May 2024

Abstract
In this paper, based on the composite structure design and analysis software ANSYS ACP, the layup design for the composite cases of the equal pole hole solid rocket motor with different stress equilibrium factors is carried out. The finite element software ANSYS Workbench is used to study in detail the effects of stress equilibrium factor on the stress level, failure degree, and burst pressure prediction of the case under a certain internal pressure. The results show that reducing the value of the stress equilibrium factor can reduce the stress level of each winding layer along the main direction of the material in the motor case and gradually transfer the maximum stress of the case along the fiber direction from the weak stress zone to the cylinder section. This is beneficial for improving the burst pressure of the case and making the burst point located in the cylinder section. However, whether the case failure is related to the selected failure theory and strength criterion, the failure results and burst pressure obtained using different failure theories and strength criteria may be different, which indicates that each failure criterion has its scope of application and limitations. Under the Tsai-Wu criterion, using the stress equilibrium equation to calculate the stress equilibrium factor can just ensure that each winding layer of the motor case does not fail under the working pressure. In summary, when designing a composite case and predicting its failure, in addition to considering whether the stress equilibrium factor taken is conducive to meeting the design requirements for the strength of the case, it is also necessary to consider the use of multiple failure criteria to study the failure of the case. Obviously, arbitrarily selecting the stress equilibrium factor is not appropriate in the above process. By analyzing the influence of the stress equilibrium factor on the strength and failure condition of the motor case, it can provide an effective reference for the design of a composite case for SRM.
Measurements of time resolution of the RD50-MPW2 DMAPS prototype using TCT and 90Sr
Authors: Debevc J. , Franks M. , Hiti B. , Kraemer U. , Kramberger G. , Mandić I. , Marco-Hernández R. , Nobels D.J.L. , Powell S. , Sonneveld J. , Steininger H. , Tsolanta C. , Vilella E. , Zhang C. 
Published: May 2024

Abstract
Results in this paper present an in-depth study of time
resolution for active pixels of the RD50-MPW2 prototype CMOS
particle detector. Measurement techniques employed include Backside-
and Edge-TCT configurations, in addition to electrons from a
90Sr source. A sample irradiated to
5 · 1014 neq/cm2 was used
to study the effect of radiation damage. Timing performance was
evaluated for the entire pixel matrix and with positional
sensitivity within individual pixels as a function of the deposited
charge. Time resolution obtained with TCT is seen to be uniform
throughout the pixel's central region with approx. 220 ps at
12 ke- of deposited charge, degrading at the edges and
lower values of deposited charge. 90Sr measurements
show a slightly worse time resolution as a result of delayed events
coming from the peripheral areas of the pixel.
Multiscale slope analysis and functional correlation with gloss reflectance from photographic papers
Authors: Bartkowiak Tomasz , Etievant David , Brown Christopher A 
Published: May 2024

Abstract
A novel multiscale 3D topographic characterization for slope is introduced. Slope is considered as a crucial parameter linking area-scale and 3D curvature analyses. Relationships between surface topography and gloss reflectance in photographic papers are used for an example application. Directional angles, characterizing slopes, are calculated two ways: normals to triangular facets (method 1), and eigenvectors of a covariance matrix based on nine points (method 2). Slope is the steepness of surface inclinations associated with the orientation of local surface features (facets). The impact of slope on gloss reflectance supports the use of pertinent geometric characterizations, i.e., alignment of geometric characterizations with the physical nature of the topographic interaction phenomena. Topographies of 24 photographic papers, were measured with a laser scanning confocal microscope and their gloss reflectance was measured with a micro-TRI-gloss gloss meter. Analyses of slope distributions with bivariate dispersion measures of directional angles and their trigonometric functions revealed strong correlations (R2 > 0.6) between slope distributions and gloss. Bivariate median deviation of secant or tangent of directional angles, demonstrated consistently high correlations across scales, magnifications, and filtrations. This study supports pertinent and useful characterizations grounded in the physics of topographic interaction phenomena to provide insights into relationships between surface topography, e.g., slope and gloss reflectance in photographic papers. This nuanced understanding has potential applications for other applications as well.
Integrated form-position measurement of large-aperture transparent elements based on stereoscopic phase measuring deflectometry
Authors: Chen Ting , Yang Peide , Lang Wei , Chen Yunuo , Wang Wei , Zhang Xiangchao 
Published: May 2024

Abstract
In the field of ultra-precision manufacturing and measurement, sub-aperture stitching is a widely employed technique for the measurement of complex optical components. Those influencing factors like system errors and numerical bias introduce notable stitching errors in the overlapped areas between sub-apertures, consequently degrading measurement accuracy. In addition, the surfaces forms, refractive indices, and positions are difficult to be specified simultaneously. In this paper, an integrated measurement method based on the stereo deflectometry is proposed, which can measure the surface form, refractive index, and relative position of large-aperture transparent components together. This method utilizes a Gaussian process regression model to decouple and predict the refractive index and relative positions of the upper and lower surfaces. Then, a robust sub-aperture stitching technique with an adaptive distance function is employed to correct the positioning errors of sub-apertures. The feasibility and effectiveness of this method are demonstrated. The final stitched surface results exhibit a measurement error of 320 nm and a thickness deviation of 28 μm.
Bioactive compounds-loaded polyvinyl alcohol hydrogels: advancements in smart delivery media for biomedical applications
Authors: Luthfianti Halida Rahmi , Waresindo William Xaveriano , Edikresnha Dhewa , Hapidin Dian Ahmad , Noor Fatimah Arofiati , Elfahmi Elfahmi , Khairurrijal Khairurrijal 
Published: May 2024

Abstract
The paper initially focuses on the characteristics of Polyvinyl Alcohol (PVA) hydrogel as smart delivery media, such as chemical stability, biocompatibility, and capacity for controlled release of bioactive compounds. Then, it discusses the effect of loading bioactive compounds into PVA hydrogel, considering their stability of delivery media, controlled release, and targeted delivery, enhancing therapeutic outcomes. Loading bioactive compounds such as diphlorethohydroxycarmalol (DPHC), curcumin, carotenoids, andrographolide, and flavonoids into PVA hydrogels can enhance biomedical functionalities. These functionalities include improved drug delivery, wound dressing efficacy, tissue engineering potential, and contact lens applications. Further, while previous review papers have extensively covered aspects such as the source of bioactive compounds, extraction methods, synthesis of PVA hydrogel, and various biomedical applications, there remains a gap in the literature in which no studies have systematically explored the loading of bioactive compounds into PVA hydrogel. This targeted investigation distinguishes our work from previous studies and contributes a novel perspective to the expanding hydrogel market. In light of the projected compound annual growth rate of 7.15% in the hydrogel market from 2021 to 2028, this study provides a pioneering overview of recent advancements in bioactive compound-loaded PVA hydrogels. Finally, this review outlines the challenges in optimizing bioactive compound-loaded PVA hydrogels’ performance and their biomedical application. In the future direction, this review explores their potential in smart delivery media, such as optimizing the loading efficiency and releasing kinetics to specific target therapeutic, crosslinking with double or triple network hydrogels, and convergence of nanotechnology with hydrogel that become frontiers in precision medicine.