Application of a Multi-Strategy Improved Sparrow Search Algorithm in Bridge Crane PID Control Systems

To address the anti-swing issue of the payload in bridge cranes, Proportional–Integral–Derivative (PID) control is a commonly used method. However, parameter tuning of the PID controller relies on empirical knowledge and often leads to system overshoot. This paper proposes an Improved Sparrow Search Algorithm (ISSA) to optimize the gains of PID controllers, alleviating adverse effects on payload oscillation and trolley positioning during the operation of overhead cranes. First, tent map chaos mapping is introduced to initialize the sparrow population, enhancing the algorithm’s global search capability. Then, by integrating sine and cosine concepts along with nonlinear learning factors, the updating mechanism of discoverer positions is dynamically adjusted, expediting the solving process. Finally, the Lévy flight strategy is employed to update follower positions, thereby enhancing the algorithm’s local escape capability. Additionally, a fitness function containing overshoot penalties is proposed to address overshoot issues. Simulation results indicate that the overshoot rates of all algorithms remain less than 3%. Moreover, compared with the Sparrow Search Algorithm (SSA), Particle Swarm Optimization (PSO), Simulated Annealing (SA), and Whale optimization Algorithm (WOA), the optimized PID control system with the ISSA algorithm exhibits superior control performance and possesses certain robustness and adaptability

N-doped graphene film-confined nickel nanoparticles as a highly efficient three-dimensional oxygen evolution electrocatalyst

A three-dimensional (3D) catalyst was fabricated by using N-doped graphene films as scaffolds and nickel nanoparticles as building blocks via a heterogeneous reaction process. This unique structure enables high catalyst loadings and optimal electrode contact, leading to a surprisingly high catalytic activity towards OER, which almost approaches that of the state-of-the-art precious OER electrocatalysts (IrO2). Moreover, the catalytic process features favourable electrode kinetics and strong durability during long-term cycling. The dual-active-site mechanism was proposed for this 3D catalyst, i.e., Ni/NiOOH and Ni-N(O)-C are both active sites. The enhanced performance is attributed to synergistic effects of N-doped graphene and Ni, which enhance the activities of both components for OER. © 2013 The Royal Society of Chemistry.Sheng Chen, Jingjing Duan, Jingrun Ran, Mietek Jaroniec and Shi Zhang Qia