In the environment where global navigation satellite system (GNSS) signals are not available, positioning based on low Earth orbit (LEO) satellites signals of opportunity (SOP) is an effective positioning solution. At present, positioning based on the single LEO constellation SOP is faced with probl...

The background pressure in vacuum chamber is an important parameter that affects the performance evaluation and plume field parameter diagnosis of electric thruster during ground tests. In this paper, a simulation analysis was made on the background pressure establishment method used in the numerica...

Crank judgement is an important link in kinematic analysis of mechanisms, which determines the motion state of the mechanism. The existing Grashof theorem and N-bar rotation theorem can well solve the problem of crank judgement of single closed-loop linkage with only R joints, but there is no genera...

Very low Earth orbit (VLEO) has unique advantages in Earth observation and scientific research due to their low orbital altitude; however, the knowledge of the atmospheric density variation in these orbits is insufficient. A preliminary analysis and discussion of the in-situ results of atmospheric d...

Lithium-ion batteries have been used in high-altitude areas and airports in China, and therefore it is urgent to investigate their cycle performance and aging mechanism in high-altitude and low-pressure environments. The aging behavior of NCM523 pouch lithium-ion batteries is analyzed in terms of el...

The discontinuous Galerkin (DG) method has been widely studied and applied because of its high-order accuracy and applicability to the unstructured grid. However, it still has problems such as poor convergence and limited robustness in numerical simulation flowfield with strong discontinuity. This p...

Control moment gyro (CMG) is the actuator for the attitude control of large spacecraft. In order to evaluate the performance degradation state of CMG, a convolutional neural network (CNN) and residual power consumption-based degradation feature extraction method is proposed. The high-precision contr...

To satisfy the requirements of satellite navigation spoofing, a satellite navigation signals purification method is proposed based on the optimal design of the array digital beamforming. Firstly, a new covariance matrix is constructed and the disparity between the max eigenvalue and the minimum eige...

To study the internal flow process of the multi-stage pressure drop valve and the influencing factors and influence laws of the pressure drop of pressure-drop-stage, based on the numerical calculation method of the Mixture two-phase flow model and the Schnerr-Sauer cavitation model, the calculation ...

The nursing robot's arm does not meet the PIEPER criterion and is constructed with a high degree of coupling and complexity. The standard genetic algorithm is difficult to accurately solve its inverse kinematics. As a result, the pose error of the end of the robot arm is relatively large. In order t...

From the perspectives of the current verification work there are a few issues need to be addressed, such as the top-level planning is not enough, the interfaces between the development organization and test organization are not well defined, the sufficiency of the verification activities is difficul...

In order to guarantee the security of wireless sensor networks, a federated intrusion detection algorithm Fed-XGB based on fog computing is proposed. The Fed-XGB algorithm extends the edge of the network by introducing fog computing nodes, reduces communication delay, improves the accuracy of joint ...

In order to solve the coupling nonlinear dynamics problem of the mechanical system and pneumatic system in the process of a new air-cooled launch device, an analysis method and optimization design method for the air-cooled launching dynamic characteristics of folding-rotor unmanned aerial vehicle (U...

An effective dimension reduction method for multivariate functional data is developed within the theoretical framework of regularized generalized canonical correlation analysis. Functional data in square integrable spaces is first projected in an integral form to a series of numeric variables, and t...

The stratospheric wind field environment has an important influence on the flight performance of near space low speed aircraft. In this paper, the modeling and prediction methods of stratospheric regional wind field are investigated based on PSO-BP neural network. Firstly, the principal component an...

The attitude control of hypersonic morphing flight vehicles cause problems of large uncertainties, such as time-varying parameter perturbation, difficulty in modeling deformation process, and complex "lumped disturbances". To address these problems, a control-oriented model for variable-sweep wing h...

Aiming at the integrated design and manufacturing of micro-channel structure parameters for printed circuit heat exchanger (PCHE), the performance optimization research of heat exchangers considering manufacturing constraints is carried out. Through fluid simulation, the influence of flow channel wi...

One of the key technologies of precision-guidance weapons is the anti-ship missile's ability to strike vital parts of a warship with pinpoint accuracy. Aiming at the problems of low detection accuracy, insu-fficient ability in feature extraction and the processing of the generated-anchors reduces th...

Considering the underactuated hypersonic flight vehicles with strong uncertainty of the dual channel attitude control strategy, practical feedback-based dual-channel control schemes are given and the robustness analysis method based on the bounded perturbation analysis of eigenvalues is proposed. Fi...

XNOR/OR-based fixed polarity Reed-Muller (FPRM) circuit area optimization is one of the current research hotspots in the field of integrated circuit design. However, the existing XNOR/OR-based FPRM circuit area optimization method has problems such as poor optimization effect and low optimization ef...

The airborne hollow fiber membrane inerting system of a helicopter is taken as the research subject.in this paper. Two temperature control systems using an electric valve and a frequency conversion fan have been designed. Based on the AMESim platform and the calculated data of the separation membran...

To meet the needs for collaborative decision making (CDM), the dynamic collaborative sequencing of departure flights in both crowded and uncrowded scenarios was systematically studied with the demands of air traffic control units, airlines and airports being taken into consideration. With a deep ana...

Aiming at engineering application problems, the multi-degree-of-freedom angular momentum envelope model of magnetically suspended control and sensing gyroscope (MSCSG) is studied. Based on the mechanical structure of MSCSG, the characteristics of radial universal deflection of magnetic suspension ro...

The echo signal of the target is the most important way for radio fuze to obtain target information. This research employs bispectral analysis to examine the echo properties of terahertz wave at different heights of plateau in shrub terrain in order that the front-end of terahertz band fuze can be i...

The conducted electromagnetic interference of the wireless charging system with the bilateral LCC structure of electric vehicles is studied. According to the standard SAE J2954, a high-frequency circuit model of the conducted electromagnetic interference of the wireless charging system with a power ...