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With the development of industrialization, the pollution of heavy metals in soil, such as lead (Pb) and cadmium (Cd), has become increasingly serious. On the other hand, the century old climate warming is considered to be the result of the significant increase in the concentration of greenhouse gases, such as CO2, in the atmosphere. These changes will affect the function and stability of the terrestrial ecosystem. Therefore, in recent years, there are more and more studies on the effects of heavy metal pollution and elevated atmospheric CO2 concentration on plants. But most of them focus on the study of the aboveground part of herbaceous plants under the action of single factor, and the study of the soil microenvironment of woody plants under the combined action of these environmental factors is relatively less. This study summarized the response of rhizosphere microenvironment to the coupling of climate warming and soil pollution, in order to provide theoretical reference for improving soil quality and ecological environment.

This article adopts a research method that combined with theoretical analysis and system design, analyzes multiple dimensions of common safety hazard events, uses support vector machine classification algorithms to filter and mine valuable information in massive data, and establishes a common safety hazard event feature set. This kind of technology can realize the automatic classification of safety hazards and extract their characteristic information, introduce the semantic analysis, word segmentation clustering method to determine the typical processing measures of events, and generate knowledge items to add methods and models to the processing measures database, which can solve the grid safety hazard data entry specifications, In-depth analysis and other issues.

The number of distributed photovoltaic power generation systems connected to the system is increasing, especially for residents and non-residents. A large amount of photovoltaic grid-connected power brings new problems to the line loss management of the distribution network. This paper proposes a theoretical calculation model of line loss for distribution network with multi-distributed photovoltaic access. This paper adopts the actual case of Shanghai Power Grid, calculates based on the mathematical model proposed, and puts forward targeted optimization suggestions by comparing the simulation analysis results.

This paper proposes a novel integrated guidance and control (IGC) method for hypersonic vehicle in terminal phase. Firstly, the system model is developed with a second order actuator dynamics. Then the back-stepping controller is designed hierarchically with command filters, where the first order command filters are implemented to construct the virtual control input with ideal states predicted by an adaptive estimator, and the nonlinear command filter is designed to produce magnitude, rate and bandwidth limited control surface deflection finally tracked by a terminal sliding mode controller with finite convergence time. Through a series of 6-DOF numerical simulations, it’s indicated that the proposed method successfully cancels out the large aerodynamics coefficient uncertainties and disturbances in hypersonic flight under limited control surface deflection. The contribution of this paper lies in the application and determination of nonlinear integrated design of guidance and control system for hypersonic vehicle.