Yunfei Liu

Aims: The rising prevalence of diabetes in young adults threatens global health and sustainable development. However, its full macroeconomic impact, especially the welfare losses beyond conventional productivity costs, has not been systematically quantified at a global level. We aimed to estimate the current and future global economic burden of diabetes in individuals aged 15–39 years using a welfare‐based approach. Methods: Using disability‐adjusted life‐years (DALYs) from the Global Burden of Disease Study 2021, we monetized health losses into a value of lost welfare (VLW) via a value of a statistical life year approach. We estimated the VLW globally, regionally and nationally, analysed its distribution by Socio‐Demographic Index (SDI) and made projections to 2050. Results: In 2021, the global economic burden was Int$1.16 trillion. Low‐SDI regions had the highest relative burden (1.21% of GDP), whereas high‐SDI regions had the largest absolute loss. Geographically, East Asia showed the highest absolute burden (Int$240.30 billion) and Oceania the highest relative impact (3.03% of GDP). Projections show the burden will more than double by 2050 to 1.32% of global GDP, driven almost entirely by type 2 diabetes. Conclusions: Diabetes in young adults represents a significant and growing macroeconomic burden. Our findings underscore the urgent need for public health strategies and economic policies focused on preventing type 2 diabetes. Such interventions are especially critical for countries with fragile health systems to mitigate substantial future economic and health losses.

With the features of broad frequency range and high impact level, laser shock is believed to have great potential for reproducing spacecraft pyrotechnic shock environments. However, there lack effective laser shock response (LSR) models and experimental studies to demonstrate the applicability of laser shock for simulating pyroshock environment in ground tests. To do so, a water-confined laser–matter interaction model is established to predict the laser-induced pressure load in this study. Furthermore, a laser shock mechanical model is built to simulate the laser-induced shock response, accounting for the elastoplastic behavior of the pure aluminum plates subjected to laser shock and the spatially nonuniform laser spot. The water-confined laser–matter interaction model and laser shock mechanical model collectively constitute a complete LSR model. A series of LSR experiments are conducted to validate the proposed model. The experimental results demonstrate a close agreement with the simulation results, and the results indicate that LSRs are capable of meeting the order of near-field spacecraft pyrotechnic shock response for the first time. Finally, the effects of the laser energy, the propagation distance of the shock wave, and the acceleration direction on the shock response of the aluminum plate are evaluated.

Acoustic Black Hole (ABH) structures have garnered significant attention from the sound and vibration scientific community, due to their exceptional capability in passive vibration attenuation. By leveraging a gradual reduction in thickness following a power-law profile, ABH structures effectively trap and dissipate vibrational energy. In the context of laminated composite materials and functional gradation, ABH beams offer novel opportunities for enhancing vibration control, particularly when combined with general boundary conditions. This study presents an in-depth vibration analysis of ABH beams, integrating laminated composites in arbitrary boundary conditions. However, the available methods in analyzing Laminated ABH structures do not take into consideration the change in number of laminates, as the ABH structure’s thickness changes. A novel method is proposed, which could be applicable, not just to ABH laminated structures, but to any laminated structures or quasi-isotropic laminated structures with uneven cuts. The influence of laminate stacking sequence and boundary conditions on modal characteristics, frequency response and vibration attenuation is comprehensively assessed. The Rayleigh–Ritz method, with Chebyshev polynomials is employed, with a focus on convergence and the effects of boundary stiffness. Results are compared with conventional beam configurations to highlight the benefits of ABH implementation with laminated composites. The results are validated experimentally, and discussed in detail. The proposed method provides valuable insights for analyzing the vibration characteristics of laminated composite structures, not just in ABH, but in any unevenly cut structures.

To carry out condition monitoring of rotor system, this paper proposes a novel detachable squirrel cage incorporating piezoelectric coating, and explains its working principle. Subsequently, the fabrication process of the piezoelectric coating is described in detail, and its surface morphology is analyzed by electron microscopy. Then, the electromechanical coupling model of piezoelectric cage bars is established, and the piezoelectric properties of the cage bars are analyzed in combination with experiments. After that, the open circuit voltage output of three piezoelectric cage bars is studied experimentally. The open circuit voltage, short circuit current and transfer charge of the squirrel cage at different rotational speeds are given. The energy output of the system under different unbalanced mass conditions and external resistance configurations is further examined experimentally. Finally, the smart squirrel cage is applied to the rotor system, and the fault diagnosis, fault classification and diagnostic accuracy analysis are carried out for the inner and outer ring faults.The results show that the proposed smart squirrel cage can realize the fault diagnosis of the rotor bearing while ensuring the structural strength, providing a new option for the online status monitoring of the rotor system.