Dark matter accounts for about 85% of all matter in the universe. Its existence is cross-verified by four independent types of astronomical evidence: galaxy rotation curves, the virial theorem, hydrostatic equilibrium, and gravitational lensing. This paper reviews the gravitational effects of dark matter on exoplanets and the applications of its existence in matter observations. A literature review and comparative analysis are used to examine the gravitational effects at three levels. At the microscopic level, dark matter particles and planets form quantized gravitational bound states, but the purely gravitational energy effect is extremely small. In terms of evolution, the gravitational lines of dark matter promote the birth of planetary systems. In terms of applications, heating signals, high-energy neutrinos, and spatial distribution mapping produced through the gravitational capture of dark matter by planets may provide new approaches to dark matter detection. The results also show that this approach has advantages in the amount of experimental data and sensitivity to low-mass dark matter. However, because the signals are weak, the dependence on models is strong, and the astrophysical backgrounds are complex, it is still at the stage of theoretical exploration. It supplements existing detection methods rather than replacing them.

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Boundary-layer transition strongly influences surface skin friction and is therefore important in laminar-flow aerodynamic design. This study combines a review of the classical transition pathway with a parametric sensitivity analysis of the semi-empirical e N method. The review traces transition from Tollmien–Schlichting wave amplification through secondary instability and Λ-vortex formation to turbulent breakdown, while highlighting the receptivity limitation that prevents N crit from being determined purely from linear stability theory. Transition prediction is then performed using XFOIL 6.99 with a NACA 0008 airfoil as a thin, near-zero-pressure-gradient proxy. Three single-variable studies examine chord Reynolds number. (10 5 -10 7 ), N crit (4–13), and angle of attack (-4 ∘ to +4 ∘ ). Increasing Reynolds number moves the predicted transition upstream from x tr /c=1.000 to 0.344. At Re=10 6 , increasing N crit from 4 to 13 shifts transition downstream from 0.556 to 0.943. Varying incidence moves transition in opposite directions on the two surfaces, spanning almost the entire chord within ±4 ∘ . These results show that e N -based transition prediction is highly sensitive to Reynolds number, the empirical N crit and even weak pressure gradients, emphasising the uncertainty introduced by unmodelled receptivity and geometric approximation.

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Multi-sensor fusion is fundamental to environment perception in intelligent connected vehicles, but its reliability depends on maintaining a consistent spatiotemporal reference among cameras, LiDAR, millimetre-wave radar, and IMU/GNSS. This review examines multi-sensor calibration from a vehicle life-cycle perspective, focusing on how calibration parameters drift, how miscalibration is detected, when recalibration should be triggered, how parameters are recovered online, how the vehicle should operate while calibration is uncertain, and how recovery should be verified. Intrinsic, extrinsic, and temporal parameters are distinguished from pairwise and joint calibration architectures, while temporal errors are further separated into fixed offsets and time-varying synchronisation effects. Calibration methods are organised by their constraint sources, including artificial targets, natural-scene structure, and motion consistency, with learning-based approaches treated as an implementation paradigm rather than a separate information source. The review further compares requirements across end-of-line production, research platforms, and in-service maintenance, showing that in-service accuracy should be defined by downstream functional tolerance. A major remaining challenge is online verification: existing residuals and consistency checks provide only indirect evidence, while accepted criteria linking calibration uncertainty to downstream safety margins are still lacking. Future research should integrate detection, recovery, degraded operation, and verification within a unified maintenance loop.

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The rapid intensification of tropical cyclones significantly increases their potential for causing disasters, and both their formation and intensification are influenced by a variety of physical conditions such as the ocean and the atmosphere. This article focuses on the analysis of the energy transfer mechanism between the ocean and the atmosphere during the formation and rapid intensification of typhoons, with a particular emphasis on the influence of ocean thermal conditions, energy exchange between the ocean and atmosphere, and the atmospheric environment on the rapid intensification of typhoons. Studies have shown that higher sea surface temperatures and the heat content of the upper ocean layer provide favourable thermal conditions for the formation of typhoons. Latent heat flux, sensible heat flux, water vapour condensation and release are important pathways for the transfer of ocean energy into the interior of typhoons. Meanwhile, factors such as environmental humidity and vertical wind shear further regulate the intensity of deep convection and circulation. Take Typhoon Bavi in 2026 as an example. During its rapid intensification phase, it had high SST and OHC, abundant water vapour and weak vertical wind shear, and significantly intensified within a short period of time. Studies have shown that the rapid intensification of typhoons is the result of the combined effects of ocean energy supply, sea-air energy exchange, and the atmospheric environment. Therefore, the prediction of rapid typhoon intensification requires careful consideration of multiple factors.

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