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Nowadays, meta-heuristic algorithms are attracting widespread interest in solving high-dimensional nonlinear optimization problems. In this paper, a COVID-19 prevention-inspired bionic optimization algorithm, named Coronavirus Mask Protection Algorithm (CMPA), is proposed based on the virus transmission of COVID-19. The main inspiration for the CMPA originated from human self-protection behavior against COVID-19. In CMPA, the process of infection and immunity consists of three phases, including the infection stage, diffusion stage, and immune stage. Notably, wearing masks correctly and safe social distancing are two essential factors for humans to protect themselves, which are similar to the exploration and exploitation in optimization algorithms. This study simulates the self-protection behavior mathematically and offers an optimization algorithm. The performance of the proposed CMPA is evaluated and compared to other state-of-the-art metaheuristic optimizers using benchmark functions, CEC2020 suite problems, and three truss design problems. The statistical results demonstrate that the CMPA is more competitive among these state-of-the-art algorithms. Further, the CMPA is performed to identify the parameters of the main girder of a gantry crane. Results show that the mass and deflection of the main girder can be improved by 16.44% and 7.49%, respectively.

Non-circular gear systems (NCGSs) are among the most widely used transmission mechanisms in bucket wheel stacker/reclaimers (BWSRs), the performance of which depends greatly on the NCGS dynamic characteristics such as the transmission efficiency, gear vibration, and gear-teeth failure. To improve the NCGS dynamical performance, a new non-circular gear transmission system is designed based on the transmission principle of non-circular gears while taking into account the special requirements of a BWSR. The newly designed NCGS comprises a sun gear, a fixed gear, and four planetary gears. By considering the time-varying meshing stiffness and the transmission error of the NCGS, a corresponding dynamical model of the NCGS is established using the Newton's second law. The dynamic characteristics of the NCGS under different working loads and speeds are then compared and analyzed. The results show that the NCGS can reduce the working speed of the sun gear as much as possible by meeting the performance requirement of the transmission mechanism. Finally, the newly designed NCGS is shown to be capable of improving the overall BWSR performance immensely.