To systematically review the research methods for the mesoscale mechanical properties of carbon nanotube-reinforced composites， this paper reviewed mesoscale analysis methods （Mori-Tanaka method， cell model method， homogenization method） and finite element simulation methods （asymptotic expansion homogenization method， Voronoi cell element method，micromechanics finite element method）. The review focused on the random sequential adsorption （RSA） and random sequential expansion （RSE） algorithms for representative volume element （RVE） and their improvements. The results showed that the mesoscale finite element method could effectively obtain the stress-strain field of materials， revealing the correlation between their macro and meso performance. It was demonstrated that the introduction of carbon nanotubes could significantly enhance the interfacial strength and interlaminar properties of epoxy resins and carbon fiber composite，and provides an important theoretical basis for the performance optimization and engineering application of composites.

To investigate the surface state of GH4151 alloy after ultrasonic shot peening strengthening and analyze its strengthening mechanism， characterization tests and numerical simulation analysis were conducted. The effects of shot diameter on surface morphology， microstructure， and microhardness distribution of GH4151 alloy under peening intensities of 0.15 A and 0.25 A were explored. The difference between the simulated roughness value and the final test evaluation data is less than 10%， confirming the reliability of the simulation prediction. At a peening intensity of 0.15 A， compared with 1.5 mm shots， the use of 2.5 mm shots results in a reduction of approximately 10.9% in roughness Ra and about 10.4% in roughness Rz. The results show that a higher shot peening intensity enhances the weakening effect on the peaks and valleys. Increasing the shot diameter improves the uniformity of the surface macro-morphology. After ultrasonic shot peening treatment， the plastic deformation layer is obvious， and the dispersion of hardness values along the depth direction is reduced. Both surface microhardness and the depth of the affected layer increase significantly， and the uniformity of the hardened layer is improved.

To enable the cockpit defogging system of a certain type of four-seater electric aircraft to meet the airworthiness requirements.According to CCAR23.773（b）， the initial design scheme of the cockpit defogging system was given.According to the idea of compliance verification of the provisions， method and steps of the ground test for defogging were designed. By carrying out the compliance verification of the defogging system， the initial scheme of the defogging system was improved based on the test results， and the test scheme of the defogging system was optimized. Finally， the verification results of meeting the airworthiness requirements were obtained， and the airworthiness verification work was completed. The cockpit defogging system and verification process studied can not only provide references for the subsequent design and airworthiness of other models， but also play a certain reference role for designers and airworthiness inspectors engaged in related work.

To address salt spray deposition in aero engine compressors in marine atmospheric environments， the motion and deposition characteristics of salt spray particles， as well as the effectiveness of thermal cleaning， were systematically investigated using numerical simulation. The deposition characteristics of salt spray with different particle sizes were analyzed using the DPM（discrete phase model）， while the atomization， impingement， and film formation processes of the cleaning liquid were simulated using a coupled VOF-to-DPM model and the Eulerian wall film model. The results show that salt spray deposition is mainly concentrated in the blade pressure surface and root regions， with a maximum total coverage of 31.38%. After thermal cleaning， the total cleaning coverage on the blade surface reaches 32.32%， with the highest coverage observed in the pressure surface of large blades （63.18%）， whereas the suction surface and blade root regions exhibit poorer cleaning performance. Experimental verification demonstrates that the positions where cleaning droplets are predicted to cover in the simulation are all cleaned in the experiments， confirming the effectiveness of the thermal cleaning method established. These findings provide a theoretical basis for optimizing online cleaning strategies.

To address the issue of high-pressure rotor seizure after engine shutdown， a fault tree analysis method based on Isograph was employed to identify the causes of the high-pressure rotor seizure. By analyzing physical re-inspection results and performing deformation compatibility calculations for typical seal clearance locations， the root cause of the seizure was determined. Corresponding corrective measures were formulated and verified through engine testing， thereby further enhancing the efficiency of the overall engine test process. This approach can provide ideas and methods for addressing other rotor seizure issues， enabling targeted preventive measures to be taken in the early design stage and refining deformation compatibility theory from an engineering application perspective.

In order to improve the control law of airborne windmilling start for turbofan engines and enhance windmilling start performance and reliability， a specific aviation turbofan engine that utilized a fuel-air ratio control mode for windmilling start was selected as the research object. Based on the results of windmilling start tests conducted on an altitude test facility， the effects of ambient temperature， cold and hot starts， flight altitude， and flight speed on windmilling start performance were analyzed. The results show that a decrease in flight speed has the most significant impact on the increase in starting time， extending it by 89%. An increase in flight altitude has a secondary effect， extending the starting time by 21%. The effects of cold weather and cold starts are relatively small. According to the test results， the correction coefficients of starting fuel-air ratio related to atmospheric pressure， Mach number， and temperature were designed. Therefore， when altitude increases， flight speed decreases， ambient temperature drops， or during cold starts， the fuel-air ratio for windmilling start is increased to shorten the starting time.

The performance differences between continuous and discrete variable design methods for topology optimization of infill structures were investigated. Based on local volume constraints， two optimization models were established： a continuous variable model using the SIMP method with the optimality criterion and a discrete variable model using the SAIP method with the canonical relaxation algorithm. Firstly， the fundamental formulations of these methods for topology optimization of infill structures were derived theoretically. Subsequently， numerical examples were utilized to conduct comparative studies from three aspects： optimization performance， clarity of structural topology design， and computational efficiency. Finally，by implementing identical initialization strategies， move limit strategies， and convergence criteria， the external interference in the algorithm was eliminated. The results demonstrate that the optimization time using the SIMP method is approximately 50% of that using the SAIP method； however， the topological designs generated by SIMP exhibit grayscale regions at structural boundaries. In contrast， the SAIP method yields topological designs with clearer boundaries and superior structural configurations， achieving about a 4% reduction in the objective function value. A theoretical reference and basis for the topology optimization design of infill structures is provided.

To address the issue of SLAM-based visual relocalization failure in unmanned vehicles under visual degradation conditions，an adaptive collaborative relocalization algorithm was proposed，which combined wheel odometry （WO） with visual odometry （VO）.This algorithm constructed a WO/VO fusion model based on error-state Kalman filter （ES-KF），enhancing the positioning accuracy of the unmanned vehicle’s path planning.To tackle the challenge of insufficient visual feature points that hinder relocalization during unmaned vehicle operation，an adaptive collaborative relocalization algorithm for WO/VO was proposed.The system included a switching mechanism between WO/VO and WO，improving the continuity of the unmanned vehicle’s localization and the reliability of path planning.Experiments were conducted and compared on the developed unmanned vehicle platform under various conditions.The results demonstrate that the ES-KF-based WO/VO fusion method significantly improves localization performance.The absolute trajectory error （ATE） is reduced by 39.1% and 59.2%，respectively，compared to VO-only and WO-only methods，and path overlap is increased by 9.2% and 11.5%，respectively.The algorithm also successfully achieves WO-assisted adaptive collaborative relocalization in visual degradation scenarios.Compared to the extended Kalman filter （EKF） and the unscented Kalman filter （UKF），the ES-KF demonstrates superior performance in both trajectory accuracy and pose estimation stability，significantly enhancing path fusion effectiveness and system robustness.

Aiming at the problem of traditional position control ignoring human-robot interaction， a novel omnidirectional mobile lower limb rehabilitation robot was taken as the object， and an adaptive interaction control strategy based on fuzzy admittance control was proposed. Firstly， the robot structure was introduced， which mainly consists of a lower limb exoskeleton and an omnidirectional mobile platform. Then， the kinematic model of the lower limb exoskeleton， dynamic model of the omnidirectional mobile platform， and motion coordination model between them were established for the subsequent control. Then， a sliding mode controller was designed to combine with the exoskeleton kinematic and motion coordination model to achieve trajectory tracking， and a fuzzy admittance controller was designed to adjust gait speed based on human-robot interaction. Finally， a trajectory tracking experiment and an interaction experiment were conducted on a healthy subject， and the results show that the control strategy has good trajectory tracking performance and can adaptively adjust gait speed according to the subject’s motion intention.

In order to effectively evaluate the fire resistance of different aviation coatings and provide a basis for the selection of aviation coatings，four types of high-performance aviation coatings， namely， 650 low molecular polyamide cured epoxy resin coatings， 2-phenoxypropane epoxy resin coatings， 2-ethyl-4-methylimidazole cured epoxy resin coatings and bismaleimide resin coatings， were analyzed. Through experiments， 14 parameter indexes were obtained for three aspects， namely， thermal stability， combustion characteristics and smoke toxicity.A comprehensive index system for evaluating the fire protection performance of the four types of aviation coatings was set up by using the analytic hierarchy process（AHP）.Based on the variable fuzzy optimization theory， the fire protection performance superiority and inferiority of the four aviation coatings were evaluated. The results of the study show that for the four types of coatings， the order of their fire protection is as follows： bismaleimide resin coatings、650 low molecular polyamide cured epoxy resin coatings、2-ethyl-4-methylimidazole cured epoxy resin coatings、2-phenoxypropane epoxy resin coatings.

To address the problems of low resource utilization，high costs and high carbon emissions of traditional single delivery tools，a joint delivery routing problem for electric vehicles and drones with a two-tier system was proposed. It considered factors such as energy consumption and carbon emissions of vehicles and drones during different delivery stages. A mixed-integer linear programming model was established， aiming to minimize the sum of fixed costs， energy consumption costs， and carbon emission costs， subject to constraints including customer time windows， vehicle and drone capacities， and battery capacities. Based on this model， a hybrid genetic algorithm was designed. Initially， an initial population was generated according to a greedy rule， and the destruction and repair concept from large-scale neighborhood search was integrated with the genetic algorithm for solving. The experimental results verify that this hybrid algorithm can effectively solve the 2E-VRPD problem， optimize delivery routes， improve vehicle-drone collaborative delivery efficiency， and reduce delivery costs.

Aims to elucidate the mechanisms through which digital transformation at the micro level influences enterprises’ new quality productivity，the micro-mechanisms of digital transformation affecting new quality productivity from the perspectives of internal control and external supervision were empirically discussed， using data from A-share listed manufacturing firms from 2012 to 2022. It was found that： corporate digital transformation is conducive to promoting the development of new-quality productivity； Internal control and external supervision positively regulate the process of digital transformation to promote the development of new-quality productivity； The higher the technological level of the enterprise， the stronger the moderating effect of internal control and external supervision； the moderating effect of external supervision is stronger than that of internal control in large-scale enterprises， while the moderating effect of both is not significant in small and medium enterprises； the more competitive the industry is， the stronger the moderating effect of internal control is， and the external supervision plays a role only in the industry with high degree of competitiveness. It is of great significance in deeply understanding the internal logic of digital transformation promoting new quality productivity at the micro enterprise level and provides a basis for enterprises to formulate rational development strategies.