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[Objective] Through the spatio-temporal dynamic analysis of landscape ecological pattern and habitat quality, the response of habitat quality before and after the implementation of soil and water conservation measures in PU River Basin of Shenyang City was deeply studied, aiming to provide scientific basis for soil and water conservation strategies in small river basins, so as to promote the coordinated growth of the eco-economy and the sustainable and healthy development of regional ecology. [Methods] Based on the land use data and Digital Elevation Model (DEM) of PU River Basin in 2000, 2010 and 2020, combined with the FRAGSTATS and InVEST models, land use transfer matrix, landscape pattern index, habitat quality and habitat degradation degree were used to analyze land use change and explore quality response situation. [Results] (1) During the period from 2000 to 2010, the cultivated land development activities in the PU River Basin were frequent, resulting in a significant decline in the proportion of forest, grassland and other land types; In the period from 2010 to 2020, the construction of the PU River ecological corridor will promote the change of land use, and the cultivated land area will flow to artificial surfaces, forests and grasslands. (2) During 2000 to 2020, the overall landscape pattern of the PU River Basin experienced a process of first becoming complete and then fragmentary. The landscape on both sides of the Puhe River formed a dense pattern of multiple elements, and the habitat in the northern edge of the urban center continued to fragment. (3) From the overall analysis of the basin, the average habitat quality in 2000, 2010, and 2020 was 0.349, 0.329, and 0.354, respectively, showing a trend of first decreasing and then increasing. The mean values of habitat degradation were 0.098, 0.112, and 0.086, which were consistent with the trend in habitat quality. With the construction of the PU River Ecological Corridor, the quality of habitat will be improved significantly in 2020, and the threats to the ecosystem will be reduced. From the analysis of spatial pattern, the northeast and southwest show obvious spatial distribution characteristics. The quality of habitat in the mountainous areas of northeast China and the wetlands of southwest China is generally good, but there is a threat of habitat degradation. [Conclusion] Under the influence of soil and water conservation measures, the ecological pattern of the PU River Basin can be and the degradation of habitat can be effectively inhibited.

Conducting laboratory accelerated simulation tests on the atmospheric environment in which aviation materials are used to obtain their long-term corrosion behavior and life degradation is an important content and foundation for the design, manufacturing, maintenance, life assessment, and life control of related materials and equipment. The laboratory accelerated corrosion tests for simulated coastal atmospheric corrosion of 2A12-T4 aluminum alloy plates is conducted, and the impact of corrosion on the fatigue characteristics of aluminum alloy plates throughout the entire coastal atmospheric corrosion process from initial pitting to later erosion is simulated. Based on the principle of equivalent fatigue life degradation, an accelerated equivalent relationship between 2A12-T4 aluminum alloy plate accelerated corrosion and atmospheric corrosion is established. The results show that the fatigue life degradation law of 2A12-T4 aluminum alloy after accelerated pre-corrosion in laboratory is consistent with that of atmospheric pre-corrosion fatigue life degradation law, which is characterized by "rapid decline period"+"platform period".

The voltage quality decline caused by the high proportion of new energy connected to power grids is a key factor limiting the capacity of new energy consumption. Therefore， an optimal reactive voltage control method based on the maximum capacity of new energy consumption is proposed. The new energy generation forecast data is used to assess the maximum generation capacity， establish the reactive voltage optimization model and solve the voltage control target at each node for forwarding decision control. According to the topological properties and operational characteristics of the regional power grids， dynamic zoning， strategy prediction， alarm blocking， and other concerning functions are designed to improve the safety and stability of the control method. The simulation analysis results of an example show that the method features ideal reactive voltage support and can promote new energy consumption in the regional power grids.

Based on the air quality data of Harbin in winter from 2015 to 2017, the national winter straw combustion data from 2016 to 2017 and the mixed single particle Lagrange comprehensive track model, Hybrid Single-Particle Lagrangian Integrated Trajectory Model (HYSPLIT), dynamic analysis of Harbin’s winter air quality status and influencing factors. The air quality data were analyzed; it was found that the main pollutants in winter in Harbin were SO2, NO2, PM10 (particles with aerodynamic diameter ≤10 µm), and PM2.5 (particles with aerodynamic diameter ≤2.5 µm); the annual air pollution situation deteriorated sharply from November and continued until March of the following year. Through the research on straw fire prevention points in Harbin, the spatial pattern characteristics and causes of persistent haze in Harbin from 2015 to 2017 were dynamically analyzed. Combining the backward trajectory model to trace the source and trend of air mass in pollution, it is found that the air mass trend is consistent with the distribution of straw-burning points. The research results show that (1) during the winter from 2015 to 2017, the overall air quality situation in Harbin improved, the number of serious pollution days decreased year by year, and the main atmospheric pollutants were PM10 and PM2.5. In October and November, the pollution concentration peaked, and after December, the pollution concentration showed a downward trend until the next spring reached the valley and (2) the most obvious time of haze in Harbin is from November to December, and it is concluded that haze events are closely related to the large number of pollutants caused by the burning of straw around Harbin, and because the northwest monsoon climate affects the air quality, the transportation of fine particles caused by the burning of straw in winter in the surrounding areas of Harbin is the main cause of serious pollution in Harbin.

Condensing the multi-dimensional digital model of green urban design, and constructing a digital method system of it progressively layer by layer. Based on this research background, the dissertation designs the spatial form of landscape architecture based on the data visualisation of nonlinear technology. The article uses the colour zoning method to design the actual scene of the garden landscape with nonlinear parameteriszation. The simulation result analyses that the proposed nonlinear algorithm has realised the efficiency improvement purpose of landscape architecture design.

This Article aims at the current high idle rate of landscaped gardens and a single overall style. The article inputs the quantitative relationship programming of the dynamic model of the urban landscape ecological city system into the Grasshopper software to obtain the urban landscape parameter growth curve, and at the same time applies the nonlinear parameterized model method to the landscape design. The research found that the feature form of the landscape garden presented in the thesis is mainly based on the nonlinear transformation of the local analysis structure feature. In the end, the thesis deeply researches the existing operating modes based on the concept of nonlinear thinking. Furthermore, it combines with information technology to supplement and update the traditional landscape construction from different perspectives.

Scheme of the MCN@OEC-loaded CSF hydrogel.

In order to improve the service life of rubber joints of standard subway gearbox boom,the causes of fatigue failure of rubber joints are analyzed,the characteristics of different structures of rubber joints are studied,a new rubber joint with oblique linear rubber free surface and rubber thickness gradient is designed,the friction amplitude and stress concentration of rubber free surface are reduced,and by using finite element analysis software,the fatigue resistance of the new structure is optimized to improve by optimizing the fatigue resistance of the new structure using FEA software,the structural design defects are improved and the service life of the product is increased.

In order to optimize the design method of the gear transmission system for urban rail transit trains in China，the mechanical strength check of the gear transmission system for urban rail trains in actual operation is performed.The loading scheme is formulated according to the design input.The gear transmission system model is created by using the 3D modeling software SolidWorks，and it is imported into the finite element analysis software Abaqus for finite element calculation.The calculation results show that the mechanical strength of the gearbox meets the requirements of train operation，and the type test results prove the credibility of the finite element calculation method.The research work has important reference value for the application of the finite element analysis method in the development and design of urban rail train gearbox.

The effects of socioeconomic changes on land use dynamics have been increasingly investigated around the world, but our knowledge of the processes underlying these effects over decades needs more attention for sustainable land management. In this research, structural equation modelling (SEM) was used to analyse the relationships among the regional economy, livestock factors and land use. We found that the land use changes were not consistent from 1990 to 2015, which was attributed to different driving forces. In the last decade of the 20th century, land use changes mainly featured the expansion of croplands at the expense of grasslands. In the 21st century, forestlands and grasslands increased due to the implementation of the Grain for Green Programme, and building lands increased because of urbanization and economic development. Our SEM results demonstrated that livestock was the major driving force of land use changes in 1990–2019, while the regional economy mainly drove land use changes in 2000–2009 in the Hulunber grassland area. Further, the added values of secondary and tertiary industries had a greater effect than the added value of primary industry and the urban population in 1990–2019; in contrast, the urban population rather than the added values of primary and tertiary industries better represented the changes in the regional economy. Meanwhile, the number of small livestock had a stronger influence than the number of large livestock and the rural population in 1990–2019, while the opposite situation was observed in a specific period (2000–2009). The socioeconomic driving factors of land use changes are divergent and dynamic over time, and regional-scale and local particularities should be brought to the forefront of land resource planning.

Based on the coupled human–environment, and taking the Hegang coal mining area (Heilongjiang Province, China) as a research area, combined with RS and GIS technologies, from the perspectives of environmental exposure, sensitivity, and adaptive capacity, the analytic hierarchy process and expert consultation methods were used to establish the evaluation index system and weight. Then the mathematical model of vulnerability assessment was constructed, and the spatial analysis method was used to dynamically identify and evaluate the vulnerability of land use in the study areas in 1994, 2006, 2010, and 2014. The results show that: 1) the vulnerability of land use shows an increasing trend from 1994-2014, and most of the landscape types show a strong dominant vulnerability; 2) the adaptive capacity of land use gradually became unstable under the influence of human–land coupling, and the land-use environment showed the trend of transformation from potential vulnerability to extreme vulnerability under the dual action of sensitivity and exposure; 3) from the type of land use, the vulnerability of coal mine land and unutilized land was relatively prominent. The two landscape types were mostly distributed in severe or extremely vulnerable areas over the past 20 years, indicating a greater degree of interference. The results provide the decision-making basis for the scientific planning and management of the land, and provide guidance for ecological restoration and environmental protection.

This paper introduces a design scheme of remote monitoring system based on Qt, the scheme of remote monitoring system based on S3C2410 and Qt, with the aid of cross platform development tools Qt and powerful ARM platform design and implementation. The development of remote video surveillance system based on embedded terminal has practical significance and value.