This paper reviews electrodynamic dust shield (EDS) systems used to mitigate dust adhesion and accumulation on optical elements, such as photovoltaic (PV) panels. The EDS system uses an electrodynamic standing wave or travelling wave, generated by applying a two-phase or multi-phase high voltage to parallel line electrodes, to transport charged particles. After presenting a brief history of the research and development of EDS systems, theoretical and numerical investigations are introduced. They elucidate the mechanism of particle dynamics in the electrodynamic field and predict cleaning performance in low-gravity and low-pressure environments on the Moon and Mars. Subsequently, the paper presents the system configuration, including a cleaner plate and power supply, and fundamental characteristics, including the effects of electrode configuration, applied voltage and frequency, and environmental conditions. It also describes the current status of two primary applications of EDS systems: the cleaning of dust deposited on large-scale PV panels used in solar power generation plants and the cleaning of optical elements, such as PV panels, thermal radiators, lenses, and mirrors mounted on rovers for lunar and Martian exploration. In addition, future challenges are discussed, and other space applications are introduced, such as cleaning of spacesuits, transport and particle-size classification of lunar regolith for the insitu resource utilization, and sampling of regolith and water ice particles on the Moon and asteroids.

The seismic performance of a long-span triple-tower suspension bridge is a critical consideration in engineering communities. To promote a better seismic design, this paper presents a parametric study on the structural seismic control using hysteretic steel dampers. The finite element model is firstly established, and an introduction to the mechanical properties of the E-shaped hysteretic steel damper is made. Then, a seismic analysis is conducted under uniform earthquake excitations. Considering the effect of wave passage, the performance of hysteretic steel dampers in seismic control is further analyzed. The results indicate that the travelling wave effect greatly affects seismic responses. Increasing the damper elastic stiffness can effectively reduce the relative displacement between the main girder and either the left or the central tower. This treatment is effective for the right tower only when the wave velocity is among 400-1600 m/s, while it makes little contribution in other ranges. At an arbitrary wave velocity, increasing the damper elastic stiffness would cause minor changes to the shear forces of side towers, while its influence on the central tower is significant. A reasonable damper design for the long-span triple-tower suspension bridge depends on an essential prior evaluation of the wave velocity based on soil conditions.