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Faced with abnormal global climate change, sponge cities are an effective response. The design of sponge cities can enhance the sustainability of the entire city, although specific quantitative effects are yet to be determined. According to the emergy theory, this article conducts a sustainability study on selected sponge city facilities in Zhenjiang City. The research results show a significant improvement in the sustainability of the study objects. Using the sustainable parameter of emergy as an evaluation criterion, there is a noticeable improvement from an initial value of 0.07 to 1.21 after the implementation of sponge measures. Additionally, the overall project design has significantly improved the sustainability of the design.

In view of the problem of emergency target handling and reasonable attack in the combat process of synthetic detachment, this paper analyzes the main characteristics of emergency target, judges the threat degree of emergency target with “threat factor function”, and controls the output of the solution by solving the objective function of “threat factor function”, so as to ensure that the emergency target with great influence can be handled quickly. By improving the weapon target allocation model and using the solution control strategy, the simulation results show that this method can effectively improve the overall strike efficiency and the processing speed of emergency targets.

The pollution problem of SMEs is an important problem to be solved in the process of China’s economic development. Based on the game theory, this paper takes the government and SMEs as the two sides of the game, constructing the game theory model of pollution control of SMEs, putting forward the strategies to promote the pollution control of SMEs according to the analysis results of the model.

Constructing the innovation network is an important means of breakthrough in the traditional manufacturers for the emerging e-commerce platform, based on two different levels of innovation network node, content and structure, YEATION and YOUPIN were chosen to analyse and research the relationship and between knowledge base and the embedding strategy of electric business platform enterprises to create innovation network. To put forward the knowledge base width wider, insufficient depth of the enterprise should adopt structural strategy give priority to relational embeddedness, on the other hand, enterprises of which the depth of knowledge base is deep and width of insufficient shall adopt strategy give priority to the embedding of structure. At the same time, it is proposed that platform enterprises should not adopt a single embeddedness strategy, but should adopt auxiliary embeddedness strategy in a timely manner.

Since complex barriers need to be passed through during the process of drilling long-distance horizontal freezing boreholes, the stability of the borehole wall at the soft and hard stratum interface is the key in controlling the deflection of the horizontal boreholes. The author puts forward to establishing the stability mechanical model of horizontal freezing borehole walls with fluid loss as the control index, starting from the stability mechanism of horizontal freezing boreholes and combined with the working conditions of horizontal freezing boreholes; selects two optimal fluid loss additives from the perspective of the molecular structure of bentonite materials, and determines the optimal formula by formulation optimization by virtue of orthogonal tests; applies the optimal formula into the long-distance pile and borehole penetration test, and validates the reliability of wall protection slurry formula materials for horizontal boreholes via comparing the water loss and soil erosion at the pile interface and analyzing the deflection rules, which is of certain value in engineering promotion and application.

Based on the principle of fiber-optic gyro inclinometer, the characteristics of horizontal freezing hole and the working conditions, it is analyzed that the horizontal hole fiber-optic gyroscope tilting technology for freezing holes is one of the most reliable methods. In order to verify the azimuth measurement error of the horizontal fiber optic-gyro inclinometer, the simulation test under the 1:1 working condition was carried out with the actual working conditions on site. Compared with the total station measurement data, it was concluded that 85.2% of the data is in measurement error within ±2°, 55.6% of the data is within ±1°, which verifies the reliability of the measurement data of the horizontal fiber-optic gyro inclinometer. At the test level of α=0.05, the azimuth test error accords with the normal distribution of μ=0.54 and σ=0.73. In the actual use process, the algorithm can be used to optimize the measurement data by taking multiple measurements and taking the average value in combination with the field conditions, so that the data can be closer to the true value.

Yellow River is an important source of water for northwest and north China, and an important strategic guarantee for the sustainable economic and social development of the Yellow River basin and its related regions. The Yellow River water allocation scheme (Scheme 1987 in short) was approved in 1987 by the State Council, which was the first river water allocation scheme in China. It allocates a total volume of 58 billion m3 of water to the 11 provinces along the river and its ecosystem. However, with the deepening impact of climate change and human activities, the Yellow River water resource and its development situations have some changes and the water resource of the drainage basin faces new situations, so it is urgent to carry out the optimization and adjustment study of Scheme 1987 under the new situation. The background and promulgation process of Scheme 1987 was reviewed comprehensively, and its implementation effect for 30 years was analyzed from two periods before and after unified dispatching. The new situation of the development of the Yellow River basin in the future was analyzed, and the work to be carried out to optimize and adjust the Scheme 1987 was prospected.

Regional water-energy-food (WEF) synergetic development evaluation is an important prerequisite for promoting regional cooperative security development effectively. Under the framework of regional WEF nexus system, the concept of regional WEF synergetic development was proposed based on the synergetic theory, and evaluation index system was constructed from the aspects of function, structure and efficiency. The development degree was evaluated by measuring the gap between the existing state and the ideal state based on the distance synergy method. Considering the synergy relationship between each subsystem, the grey correlation analysis method was used to determine the pull factors between each subsystem, and then the synergy degree was calculated. The synergetic development degree was calculated by integrating development degree and synergy degree. This method was used to analyse the WEF synergy development degree of Ningxia Hui Autonomous Region in China from 2001 to 2015. The results show that the WEF synergetic development of Ningxia was increasing but still at a low level, food subsystem had significant pull function to the water and energy subsystems. While improving the development degree of each subsystem, Ningxia needs to strengthen the collaborative development among the subsystems to improve the synergetic development of regional water, energy and food.

The sharp 90°corner of bow found on American Tarawa class general amphibious assault ship LHA-1 will produce large separated region in the airwake over the ship, and the turbulence in the separation region seriously affects the operation safety of the helicopter. In order to reduce the separation in bow region of the LHA-1, and optimize the helicopter operating environment, the numerical simulation method is used to study the influence of the bow flap on the airwake of LHA-1. The study results show that: the ANSYS k-ε two equation model based on the hybrid grid can be used to predict the steady-state characteristics of the ship airwake; the bow flap can improve the flow field downwind of the flap installation position, and the impact range can cover two spots; in headwind, the optimal installation angle of the bow flap is 15°~25°. The research results of this paper can provide modification and improvement reference for the amphibious assault ship in-service and under construction, so as to achieve the purpose of optimizing the ship airwake, thereby improving the safety of helicopter landing process and extending the service life.

System degradation was usually caused by multiple-parameter degradation. The assessment result of system reliability by universal generating function was low accurate when compared with the Monte Carlo simulation. And the probability density function of the system output performance cannot be got. So the reliability assessment method based on the probability density evolution with multi-parameter was presented for complexly degraded system. Firstly, the system output function was founded according to the transitive relation between component parameters and the system output performance. Then, the probability density evolution equation based on the probability conservation principle and the system output function was established. Furthermore, probability distribution characteristics of the system output performance was obtained by solving differential equation. Finally, the reliability of the degraded system was estimated. This method did not need to discrete the performance parameters and can establish continuous probability density function of the system output performance with high calculation efficiency and low cost. Numerical example shows that this method is applicable to evaluate the reliability of multi-parameter degraded system.

Zn-Al-Mg alloy coating attracted much attention due to its high corrosion resistance properties, especially high anti-corrosion performance at the cut edge. As the Zn-Al-Mg alloy coating was usually produced by hot-dip galvanizing method, solidification process was considered to influence its microstructure and corrosion properties. In this work, a Zn-Al-Mg cast alloy was melted and cooled to room temperature with different solidification processes, including water quench, air cooling and furnace cooling. Microstructure of the alloy with different solidification processes was characterized by scanning electron microscopy (SEM). Result shows that the microstructure of the Zn-Al-Mg alloy are strongly influenced by solidification process. With increasing solidification rate, more Al is remained in the primary crystal. Electrochemical analysis indicates that with lowering solidification rate, the corrosion current density of the Zn-Al-Mg alloy decreases, which means higher corrosion resistance.