There are complex flow phenomena in the inlets of the air-breathing hypersonic vehicles, such as boundary layer transition, flow separation, and shock/boundary layer interference. Deep understanding and effective control of these complex flow phenomena are the key to realizing effective operation and performance improvement of hypersonic vehicles. The current research progress of shock/boundary layer flow control technology in supersonic inlets is first reviewed from two aspects:passive control and active control；their effectiveness and drawbacks are described. Meanwhile, with the development of hypersonic vehicle towards the direction of wide velocity domain, large airspace and high Mach number, the previous flow control technology based on active and passive control cannot meet the requirements of hypersonic vehicle follow-up control. As a result, the multi-field control methods represented by plasma have become the focus of supersonic inlets flow control. However, the existing experimental research methods are difficult to carry out detailed research on flow control mechanisms, and there are still many places worth exploring. In this paper, relevant suggestions are put forward for the next step of research in addition to summarizing.

The anti-yaw vibration devices currently used in high-speed trains are hydraulic dampers, whose damping characteristics cannot be adjusted according to the changes in the vehicle's operating state and environmental conditions, resulting in poor ride quality and stability for the vehicle. A semi-active damper based on magnetorheological technology combined with intelligent control technology can solve this problem. In this paper, a three-coil magnetorheological damper has been developed with adjustable damping characteristics based on the technical specifications of the anti-yaw damper. The multi-physical field of the damper is simulated, and damping performance of the damper is tested under different excitation currents, amplitudes, frequencies, and coil combinations. The results show that the magnetic circuit design of the damper is reasonable and complies with the technical requirements for anti-yaw dampers, with a maximum output force of 46 kN and an adjustable dynamic coefficient of 28. In addition, an analysis is conducted on the magnetic field distribution at varying coil spacings. The findings indicate that a critical distance exists between the coils, and the critical distance of this damper is 0.69 times the width of the coil, beyond which the magnetic field distribution becomes non-uniform. The change in magnetic flux density at the effective damping channel will stop when a certain part of the magnetic circuit reaches saturation.

With the development of civil aircraft design technology, the focus of today's passenger aircraft design transits from structural safety to cabin comfort, of which the vibration comfort is a key factor. From the perspective of passenger vibration comfort, We carried out the vibration transfer path test of a certain type of passenger aircraft under three working conditions, namely, the cruising condition, the low-altitude flight condition, and the runway running condition. Based on the test data of these conditions, the Vibration Transfer Path models were built, and the key factors affecting the vibration comfort were studied. The following conclusions are drawn:Under the cruising and low-altitude flight condition, the cabin vibration response mainly comes from the coupling of engine rotor excitation and the structure at the fundamental frequency and the double frequency；under the runway running condition, the vibration response in the cabin comes from the coupling of the main landing gear excitation and the structure in the low frequency range（especially 50 Hz）. This test not only provides a basis for the vibration reduction and isolation design of passenger cabins, but also fills the gap of the vibration comfort test and verification platform for all passenger aircraft in China.

In order to determine the influence of aggregate irregularity on the mechanical properties and failure morphology of concrete, Python programs were developed to generate randomly distributed aggregate models with different sharpness in ABAQUS, and the 0-thickness cohesive element and variable-thickness solid interface transition zone（ITZ）were established respectively. First, the reliability of model was determined by changing mesh size and friction coefficient between the loading pad and concrete compared with the experiment. Then, the quality of two ITZ modeling methods was analyzed. Finally, the uniaxial compression mechanical behavior of the three-dimensional meso-concrete model was analyzed from the aspects of stress-strain curve, fracture propagation, and energy dissipation. The simulation results show that the 0 thickness cohesive ITZ and the solid thickness ITZ model can predict the compressive strength of concrete, and the stress-strain curve and failure morphology of the ITZ model with solid thickness are more consistent with the experiment. The fracture propagation of concrete is obviously affected by the shape parameters of aggregate. The interior and surface of the spherical aggregate model are penetrating cracks. The strain energy of polyhedral aggregate model is larger, and there are many micro-cracks in the concrete, the possibility being compressed and destroyed into more fragments is higher. With the increase of aggregate irregularity, the compressive strength of concrete increases slightly, but the peak strain is not affected.

Aiming at the demand for torsional capacity of high-power offshore wind power supporting structure, the full-range torsional mechanism of tapered concrete-filled double skin steel tubular（TCFDST）members was examined under the large hollow ratio, high taper degree, and out-of-code diameter-to-thickness（D/t）ratio. The characteristics of torque-angle curve could be divided into the elastic stage, elasticplastic, plastic strengthening stage, and failure stage. Influence of key parameters on ultimate bearing capacity and stiffness was revealed. The hollow ratio and strengths of steel and concrete were positively correlated with the ultimate torque and stiffness；D/t ratios of outer or inner tubes had negative relationship to it；the axial compression ratios had positive relationship within the limited value，and inversely，it was negatively correlative. A method based on laminated tube theory was proposed to calculate the torque-angle curves of TCFDST members. Subsequently，the hierarchical integration method was established and verified based on the Chinese code and relevant literature，for calculating the ultimate torsional capacity of concrete-filled double skin steel tubular members，and the difference of various methods in determining N-T curve was also analyzed. The research results in this paper can provide valuable reference for the application of TCFDST members with large hollow ratios，large taper degree，and out-of-code D/t ratios in wind power projects.

In the past decade, approximately one-third of civil aviation safety incidents have been related to landing, with hard landings comprising one-fifth of these landing-related incidents. Hard landings not only damage aircraft structures but also can lead to aircraft destruction or loss of life in severe cases. However, statistical data on hard landings remain limited. This paper systematically analyzes hard landing criteria through a review of quantitative standards, simulation analysis, and machine learning techniques. It also conducts a statistical examination of 53 typical hard landing incidents of mainstream aircraft such as Boeing-737 and Airbus-A320 over the past decade, offering a detailed exploration of common structural damage patterns associated with hard landings. Results show that heavy landing incidents often cause damage of different degrees to the aircraft's landing gear, fuselage, wings, and other key components. Moreover, the extent of damage differs significantly among various types of heavy landing incidents.

Hypersonic aircraft face extremely high aerodynamic resistance and heating during flight, posing a threat to flight safety and stability. Taguchi-gray correlation method is utilized to study the impact of size on the resistance and heat reduction performance of hypersonic aircraft. An orthogonal test is conducted, wherein design factors such as spike length-diameter ratio, airway diameter ratio, pneumatic disk diameter ratio, and lateral jet angle are considered. The response targets comprise total flight resistance, peak pressure coefficient, and Stanton number. Test results are obtained through numerical simulation. The findings indicate that the flight resistance is most significantly affected by the length-diameter ratio of the spike，while the lateral jet angle has the least effect. In regard to the peak pressure coefficient and Stanton number，the size factors exhibit a similar rank of influence. Among these factors，the length-diameter ratio of the pneumatic disk exerts the most significant impact. Increasing the length-diameter ratio of the spike and the diameter ratio of the pneumatic disk can effectively improve overall resistance and heat reduction performance. However，it should be noted that as the size increases，the lifting efficiency gradually diminishes. In comparison to the optimal group of orthogonal design，the optimized configuration demonstrates an overall performance improvement of 4.6%，thus indicating a favorable optimization effect.

Large flexible appendages of flexible spacecraft are characterised by their large scale and low stiffness, resulting in vibration of large flexible appendages that can seriously affect the attitude precision of the spacecraft. Information fusion preview control is combined with fuzzy control to construct the attitude controller. According to the information fusion theory, the spacecraft's desired trajectory and system dynamics information are fused, the optimal preview control law is derived. The optimal preview control law can be easily obtained due to the information fusion control has a simple design process and low computational burden. In real engineering, the control torque generated by the actuator is limited. The fuzzy controller is employed to adjust the parameters of the control law on-line in order to satisfy the requirements of limitation. Simulation results show that the designed control strategy with high control performance can effectively suppress the vibration of the flexible appendages, and the attitude angle can reach the desired value accurately and quickly. The proposed control strategy can be served as a reference for the engineering application of large flexible spacecraft attitude control.