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The factors influencing the external corrosion rate of buried oil pipelines are extremely complex, and the interactions between these factors make accurate prediction of the pipeline corrosion rate challenging.Response surface methodology can analyze the interactions between various influencing factors.Therefore, this study considered four affecting factors: pH value of the soil surrounding buried oil pipelines, Clconcentration, NO3－ concentration and SO42－ concentration.Experiments were designed using response surface methodology to establish a prediction model for pipeline corrosion rates in soil environments.Regression and variance analyses were performed to evaluate the model’s effectiveness and accuracy.The established response surface methodology prediction model was compared with linear regression and PSO-BP prediction models.Results showed that the difference of lack-of-fit terms in the prediction model based on response surface methodology was not significant, and the model itself passed the significance test, demonstrating its reliability.Compared to the other two models, the response surface methodology model had the highest coefficient of determination (R2) of 0.941 8, and the smallest mean absolute error, mean relative error and root mean square error,which were 0.0205,4.53%and 0.027 7,respectively.These results verified the accuracy of the response surface methodology prediction model, showing that it could accurately assess the external corrosion rate of pipelines and provide a reliable basis for developing protection measures and maintenance plans for pipelines.

Strategic evaluation is the key link of military strategic system and capacity building. Selecting and evaluating the system construction scheme can optimize strategic decision-making and improve strategic management level to a certain extent. This paper constructs an intelligent selection analysis framework of "prospect cost" system construction scheme based on MATE, and uses NSGA-Ⅱ intelligent optimization algorithm to find the Pareto front of alternative scheme in multi-dimensional tradeoff space, which improves the problem of large data volume. Taking a joint operation system as an example, the effectiveness of the proposed method is verified, providing theoretical support for the optimization and evaluation of system construction scheme.

Variable camber wing is one of the key research directions of advanced aircraft in the future. The inhe-rent contradiction between the rigidity of wing structure and the bending deformation ability is the difficulty in the design of variable camber wing structure. In this paper, a new structure and function integrated variable camber wing structure is designed. Based on the inductive motion mechanism of mimosa in nature, on the one hand, a double-layer array M-type elastic connector is arranged in the elastic deformation zone of the variable camber ribs to meet the requirements of structural stiffness and flexible deformation. On the other hand, the aerodynamic muscle is embedded in the ribs to meet the airfoil deformation drive while maintaining the overall airfoil structural stiffness. Through simulation analysis and experimental test of the prototype, the results show that the variable camber wing design can meet the camber change effect of 13.5° upward and 9.5° downward, thus verifying the feasibility of the variable camber wing structure design.

Wetland resources play an important role in maintaining the balance of surface ecosystem. Based on multi-source remote sensing images, this paper studies the spatial and temporal distribution characteristics and driving factors of wetland resources in Nanliu River Delta by using human disturbance index and "3S" technology. The results show that: (1) The total wetland area has shown an overall growth trend from 2005 to 2019, with the total wetland area increasing from 77.33 km2 in 2005 to 87.55 km2 in 2019. (2) Coastal wetland types have the fastest change rate, annual rate of 36.31%, followed by fish ponds and rice fields, the annual rate of 3.40% and 3.31% respectively. (3) The area of wetland is greatly affected by the change of river water and sediment and the change of management policy. (4) The degree of human disturbance to the coastal wetlands in the delta area increases year by year, and gradually develops to the coastal areas.