At present, the world is vigorously promoting the development of the electric vehicle industry. As a key technology in the field of electric vehicle energy replenishment, wireless charging technology has received extensive attention from the academic and industrial circles. The research on improving the charging efficiency of wireless charging technology has become a hot spot in the field. In this paper, the development history of the magnetic coupling resonant structure is reviewed. The traditional DD coil, DDQ coil, D4 coil, D4 Q magnetic coupling structure, cooperative coil wireless charging system, integrated Boost active bridge power converter, and other typical structures are systematically introduced and compared. The advantages and disadvantages of various technical schemes are summarized, and the future development trend of wireless charging technology is prospected. The research results can provide reference and guidance for the development and application of subsequent wireless charging technology. This research not only provides theoretical support for optimizing existing wireless charging systems but also offers direction for the innovative design of future high-efficiency magnetic coupling mechanisms.

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Single reinforcement learning strategies tend to be frequently traded and it's also not very good at risk control. This article puts forward some quantitative trading methods. This method uses the Qwen3:4b to lead the PPO. This paper is mostly going to be talking about the candidate trading action that comes out of a PPO. And it is hoped that this design will be able to run more smoothly. This paper will use the daily data of the publicly available SPYETF. The PPO is used to output initial trading actions. The Qwen3:4b model then makes a review of the said action in an offline setting and labels it either keep or drop. After that, this paper learns the rule by using a small agent model with these labels. And this small model would do the action filter thing when running the system online. Experimental results show that there are 467 action interceptions after using the new method and then the annualized return and its ratio will be reduced. That means it stopped some of the redundant actions but didn't do much for helping with key decisions. In summary, this paper shows that it can be done, technically speaking. The following will need more varied datasets to improve this system further.

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With the rapid development of high-frequency, high-power electronic systems, traditional silicon-based devices are no longer sufficient to meet the application requirements of high efficiency and high power density. Gallium nitride (GaN) is a wide-bandgap semiconductor material with excellent electrical and thermal properties, and is currently an important research subject for next-generation power electronic devices. Enhancement-mode (E-mode, normally off) GaN high electron mobility transistors (HEMTs) have attracted widespread attention due to their higher security and simpler driving requirements. This paper systematically reviews the main technical approaches to realizing E-mode GaN HEMTs, including fluorine ion implantation, MIS structures, and p-GaN gate technology. Its working mechanism, structural characteristics, advantages and disadvantages were analyzed and compared. The main performance enhancement technologies, including interface state control and field plate structure optimization, were thoroughly examined. In addition, important issues such as current collapse and short-circuit protection were analyzed in the context of practical device applications. Finally, the development trends of GaN devices are discussed from an application perspective. With continued advances in materials, device structures, and packaging technologies, GaN devices are likely to become increasingly important in high-frequency and high-power-density power electronic applications.

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Hexagonal boron nitride (h-BN) has emerged as a versatile quantum material platform that combines an ultrawide bandgap (UWBG), a two-dimensional van der Waals (vdW) structure, and exceptional chemical stability. These features make h-BN an attractive host for point defects that can act as single-photon emitters (SPEs) and, in certain cases, spin-active centers. This review examines h-BN from three connected perspectives: the structural and electronic properties of the material platform, the nature and engineering of the quantum emitters, and the integration of these optically and spin-active defects into functional quantum components. Particular emphasis is placed on the atomic and electronic structures of the proposed defects, controlled fabrication and engineering approaches, and the resulting optical and spin-related functionalities. Demonstrated applications in integrated quantum photonics, electrical control, and sensing are also summarized, together with the major bottlenecks that still limit practical deployment. Overall, h-BN is argued to be valuable not merely as a host of quantum emitters, but also as a platform where defect physics, material synthesis, and device engineering and integration can be linked. The future of h-BN quantum technology will depend on moving beyond emitter discovery toward defect design supported by theoretical screening, targeted creation, correlative characterization and device-aware optimization.

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