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Climate change significantly impacts ecological resistance and ecological corridors. However, the difficulty in evaluating this impact lies in two crucial issues: (i) the uncertainty arising from spatial heterogeneity, and (ii) the diversity of impacts arising from this uncertainty. A set pair analysis (SPA) model is designed to assess the impact of climate change on ecological resistance and ecological corridors for addressing the aforementioned problems. First, the ecological resistance and corridors under different climate change scenarios are simulated. Then, the five-element connection number is used to reflect changes in ecological resistance and corridors influenced by climate change and uncertainty. Finally, the influence indices are constructed to quantify the three distinct impacts of climate change on them. The evaluation results for Jiangxi Province are as follows. (i) The province’s UR index values are 0.085, 0.127, 0.351, 0.501, and 0.468 under five climate change scenarios, respectively. The impact of climate change on ecological resistance is rapidly deteriorating, and the central region is the high-value center for future ecological resistance. (ii) The values of UC in the central and southern regions range from − 0.568 to − 0.320 and from − 0.816 to − 0.446, respectively. In the two regions, the assessments of the impact of climate change on ecological corridors are negative, which results in a reduction in connectivity. (iii) The crucial meteorological risks with the greatest impact on ecological resistance and corridors are floods and high-temperature disasters. (iv) The proposals for Jiangxi Province to address climate change are as follows: enhancing flood prevention, improving high-temperature monitoring, and establishing an ecological management system. (v) The SPA model can effectively assess the different impacts of climate change with spatial uncertainty on ecological resistance and corridors.

The Bayu terraced human settlement is an on-site living cultural heritage site that responds to natural features such as mountainous landforms and seasonal hydrology. Research into the site selection, technology, and combination of Bayu terraced human settlements can provide historical insight for the construction of resilient urban and rural developments in the southwest mountainous areas and the simultaneous protection of small and micro wetlands. Complete and representative remote sensing images of terraced fields in the Bayu area, combined with historical data analysis and field investigation using the visual landscape schema language, this study analyzed the single-terraced water conservancy technology, the spatiotemporal combination model of this technology, and the three construction characteristics of the terraced human settlement environment. As a result, the landscape schema system of the Bayu-terraced human settlement system was constructed. First, the research found that, in response to the Bayu Mountain topography and the rainfall characteristics of "spring drought and summer flood," a series of in-terrain terraced water conservancy technologies have been formed, such as winter paddy field for the autumn and spring, flushing fields for flood discharge in the summer, and hoarding paddy fields for closing water in all seasons. Second, Bayu terraced water conservancy technology forms a water resource management model of "autumn storage, winter fertility, spring ploughing, summer drainage" adapted to "spring drought and summer flooding", and a combination of "high storage, low irrigation" that conforms to the geomorphology that is formed. Finally, the terraced human settlement responds to the difference in water safety under the influence of geomorphology, presenting an "organic dispersion type" terraced human settlement pattern in low-mountainous hilly areas where the intersecting terraced base and the conservation forest and the scattered residential patches nest occlusion. The conservation forest is a "large area concentration type" terraced human settlement pattern in low-mountainous hilly areas where the intersecting terraced base and the conservation forest and the scattered residential patch nest in occlusion. In summary, Bayu terraced water conservancy technology types, combination methods, and the construction mode of terraced human settlements in mountainous topography integrate with Bayu's unique geographical geomorphology and hydrological conditions. These are important for the current low-impact development and construction of urban and rural areas and the protection of traditional construction wisdom. There are also positive references.

A monitoring device for distributed photovoltaic power stations has been developed to diminish the impact of intermittent and random power generation on the grid voltage and frequency. Firstly， the basic principle of the device and the design of hardware and software are introduced. Secondly， to give full play to the inverters' fast and continuous reactive power and active power adjustment capability， an improved incremental PID （proportional-integral-derivative） control and primary frequency modulation curve are used for reactive power/voltage control and active power/frequency control respectively. Finally， the simulation results， reactive power following test， primary frequency regulation test， and on-site voltage regulation test results have verified the device’s enormous voltage regulation and frequency regulation capabilities.

This paper proposes a nonlinear electromagnetic-thermal-velocity coupling model to study the insulation performance of converter transformer, in which the saddle-like electric-stress dependence is considered under compound alternating current-direct current (AC-DC) voltage situation. Firstly, the conductance of transformer oil and oil-immersed pressboard have been measured through constructed three-electrode experimental system. An interesting electric-stress characteristic, which is saddle-like electric-stress dependence is obtained and counted in the thermal-insulation analysis in the proposed model. Then, the high-order harmonics of compound AC-DC voltage have been considered in the built electromagnetic-thermal-velocity coupling model. Additionally, the impact of non-uniform temperature result has been mapped to the electric field domain through interpolation method, due to different meshes between the flow-thermal and electric fields in accordance with distinct computational characteristics. Finally, the performance of nonlinear thermal-electric coupling properties, including saddle-like electric-stress dependence, have been considered in the proposed coupling model. Results determine that saddle-like thermal-electric dependent properties would considerably change insulation capability, compared with results from the traditional method. Even intensity field of some sampling points could jump more than 1.6 kV/mm. Therefore, it is essential to evaluate the insulation design by practical saddle-like electric-dependent properties.

Two C19-diterpenoid alkaloids, homochasmanine (compound 1) and 14-debenzoylfranchetine (compound 2), were isolated from the roots of Aconitum handelianum. Their structures were elucidated by one-dimensional and two-dimensional nuclear magnetic resonance (NMR) techniques, including 1H NMR, 13C NMR, DEPT, 1H-1H COSY, HSQC, HMBC and NOESY. The 1H and 13C NMR signals of the compounds were completely assigned.