Polymer-based capacitors are very promising for high-power systems due to their high power density and ultrafast charge–discharge speed, yet reaching high dielectric constant and high breakdown strength simultaneously in dielectric polymers required by high-performance capacitors still remains a huge challenge. Herein, poly(vinylidene fluoride- co-trifluoroethylene) (PVDF-TrFE) and poly(vinylidene fluoride- co-hexafluoropropylene) (PVDF-HFP) were coaxial electrospun in core–shell structured fibers to create locally inhomogeneous microstructures deliberately. Through adjusting the functional group HFP/TrFE monomer ratio, P(VDF-HFP)/P(VDF-TrFE) hybrid polymer films with topological composition distribution have been elaborately designed, enabling gradient polarization distribution from core to shell. Compared with homogeneous hybrid films of the same composition, the core–shell structure significantly boosts breakdown strength, thus resulting in a significantly improved energy storage capacity. At an HFP/TrFE monomer ratio of 10:1, an optimal comprehensive energy storage performance has been achieved with Ue ∼ 20.7 J/cm3 and efficiency 67.8%; moreover, the film could maintain its energy storage performance after 106 charge/discharge cycles without reduction. Molecular dynamic simulation and finite element analysis have been employed in combination to reveal the dipole moments distribution at the molecular level and polarization distribution at the microscale, which further demonstrates that elaborate polarization distribution adjustment is an effective strategy toward high-performance electrostatic energy storage capacitors.

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Medium/distant maritime rescue is significantly important in the development of maritime business. For typical medium/distant maritime rescue, the range limitation of helicopters and many difficulties between helicopter and ship cooperation lead to unsatisfactory rescue results. Compared to helicopters and ships, amphibious aircrafts could effectively solve the problems faced by helicopters and ships and meet the medium/distant maritime rescue demands with their long cruise range, high speed, high rescue capability and surface landing capability. Therefore, a time-domain planning method (TPM) based on the k-means* clustering algorithm and the genetic algorithm* is proposed in this study for the surface rescue process (SRP) of amphibious aircrafts in medium/distant maritime rescue. To simulate the SRP of amphibious aircrafts, an agent-based simulation environment of medium/distant maritime rescue was constructed based on the Python platform. Finally, a case study was carried out to verify its effectiveness and applicability. The results show that the TPM exhibits satisfactory rescue results for the SRP of the amphibious aircraft and that less than 1 h of delay time is recommended for the amphibious aircraft to rescue the persons in distress by using TPM.

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