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As a "testing ground" for a new round of institutional innovation, China's pilot free trade zones (FTZs) have created favorable development conditions for listed companies and significantly influenced their sustainability performance. Utilizing data from Shanghai and Shenzhen A-share listed companies from 2010 to 2022, this study uses the establishment of FTZs as a "quasi-natural experiment" and measures corporate sustainability performance by combining financial and environmental performance. A PSM-DID model is constructed to explore the impact of FTZ construction on corporate sustainability performance. The findings are as follows: (1) The establishment of FTZs significantly enhances both the financial and environmental performance of companies. (2) FTZs promote corporate sustainability performance by reducing transaction costs and improving corporate innovation levels. (3) The establishment of FTZs has a significantly positive impact on the sustainability performance of companies in highly competitive industries, non-labor-intensive industries, high-tech enterprises, and large-scale companies. This study reveals the impact and transmission mechanisms of FTZs on corporate sustainability performance, providing new empirical evidence for the future direction of corporate sustainable development in China. [ABSTRACT FROM AUTHOR]

Wind energy is a good alternative to fossil fuels, as the use of fossil fuels has seriously exacerbated the emission of greenhouse gases such as carbon dioxide and has greatly affected the environment. Conventional AC wind farms and AC transmission systems inevitably face problems involving reactive currents and overvoltage in the context of large-scale, large-capacity, and long-distance transmission. However, the use of all-DC wind turbines, together with DC convergence and DC transmission systems, has obvious advantages over AC transmission in terms of transmission losses and expandability. Such technology does not require bulky frequency transformers and can well solve the aforementioned problems of reactive currents and overvoltage. This paper proposes a new series–parallel structure for an all-DC wind power generation system. The series end uses a DC/DC converter based on the Cuk circuit to solve the current consistency and power balancing problems of the series wind turbine through current control, whereas the parallel end uses a large-capacity DC/DC converter based on the capacity transfer principle, to solve the problem of voltage consistency at the grid-connected end. The series part is used to increase the voltage level of the system, which can reduce the huge construction costs of offshore platforms, and the parallel part is used to increase the capacity of the system, which enables its incorporation into large-scale wind farms to achieve the replacement of fossil fuel energy. [ABSTRACT FROM AUTHOR]

Human–machine cooperative driving is an important stage in the development of autonomous driving technology. However, in emergencies, the problem of vehicle stability control for human–computer cooperative autonomous vehicles is still worthy of attention. This paper mainly realizes the stability control of the human–machine cooperative driving vehicle through active steering and considers the influence of the change of vehicle speed on the vehicle stability control performance. Therefore, a vehicle stability control method based on the superposition of steering torque is proposed, in which the Takagi-Sugeno fuzzy model is used to solve the variable parameter problem. Firstly, a vehicle system model with steering moment as input is established to ensure that the driver can participate in the steering control. Secondly, the nonlinear T-S fuzzy model is established by fuzzifying the local linear model. Then, the parallel-distributed-compensation (PDC) method is used to design the vehicle stability controller, and the asymptotic stability of the system in the range of variable parameters is proved by using the Lyapunov stability principle. Finally, the simulation and experimental results show that the control method can improve the handling stability of the human–machine cooperative driving vehicle under the condition of vehicle speed variation. [ABSTRACT FROM AUTHOR]