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In view of the high dissolved organic matter and salt content of the Mariculture wastewater in coastal industrial clusters, because that moving bed biofilm reactor (MBBR) normally faces the unbalanced carbon -nitrogen ratio and long flow, MBBR is rarely used for wastewater treatment of mariculture wastewater. Moving bed biofilm reactors of magnetic photocatalysis (MPBR) were treated with mariculture wastewater and constantly purified wastewater on a seawater ranch in Hebei. Results show that this biofilm colonization is completed faster than the other MBBR or magnetic photocatalysis microsphere. That typical constituents in this biofilm were confirmed by fourier transform infrared spectroscopy (FTIR). Pyrosequencing of 16srRNA revealed that SphaeroCalus was the predominating microbial community in MPBR. Therefore, the MPBR will be a promising alternative for the mariculture wastewater. These processing techniques can effectively reduce the risk of impact load on seawater ranch in Northern coastal areas.

With the expansion of metro network, the large passenger flow in peak hours has brought great challenges to metro operation. While upgrading the security inspection, the traffic efficiency of passengers in metro stations has also been affected. Considering public security and security inspection efficiency, using the method of passenger credit rating to establish a differentiated security inspection mode has become the development direction of intelligent security inspection in the future. It is necessary to study the passenger credit evaluation system due to a lack of research on metro passenger credit scoring. However, previous research focused on static credit evaluation rather than dynamic credit evaluation. This paper introduces motivation factor, time weight and night safety reduction coefficient to conduct dynamic passenger credit evaluation.

Objective: In order to evaluate the sustainable development ability of the supplementary medical insurance fund of a large state-owned enterprise in Anhui Province, this paper puts forward the countermeasures to promote the sustainable development of the supplementary medical insurance fund of enterprises. Methods: By constructing PSR evaluation model and using entropy method to determine the index weight, the comprehensive evaluation value of sustainable development ability of supplementary medical insurance fund of a large state-owned enterprise in Anhui was calculated. Results: Horizontally, the highest comprehensive ability is the headquarters of the large state-owned enterprise, which is 0.430, and the lowest is Qingyang County, which is 0.147; Vertically, the comprehensive evaluation value of the sustainable development ability of enterprise supplementary medical insurance increased from 0.200 in 2016 to 0.239 in 2020, with an average annual increase of 4.55%. Conclusion: The influence of pressure factors on fund operation in different regions is quite different, and the development among regions is unbalanced. It is necessary to improve the management level of enterprise, enhance the fund raising ability, pay attention to overall planning and top-level design, promote regional coordinated development as a whole, continuously improve the fund investment management ability, and actively broaden the fund investment channels.

Thanks to the complex underground environment that coal mines enjoy, drill rods for mining are vulnerable to corrosion during operation. To investigate the impact of the corrosion defects on the residual intensity of the drill rod, a relational expression of stress versus corrosion rate in the conditions of uniform and local corrosions is deduced based on the theory on mechanochemical effects; building on this, a spherical corrosion defect is developed in the joint of a φ73 mm drill rod while it is exerted with a make-up torque, an axial force and a bending moment. So it is found that, when the corrosion defect is under pressure, the bending moment plays a certain role to inhibit its increase, however when it is under tension, the bending moment plays the role to drive its increase so as to quicken its corrosion rate while the impact of the change in the corrosion detect depth is much greater than that of the radius. The result from the research provides a basis to evaluate the residual intensity of the drill rod and theoretical basis to protect drill rods from corrosion.

Passive buildings can achieve energy saving goals through their own spatial form, envelope, building materials and structural design. However, at present, there are many problems in the development of passive buildings in China, such as inadequate foundation, unreasonable passive design, which make the development of passive buildings have many obstacles, not conducive to the promotion of the construction industry. Therefore, this paper analyzes the obstacle factors of passive buildings and puts forward reasonable solutions for reference.

Real-time semantic segmentation has become crucial in many applications such as medical image analysis and autonomous driving. In this paper, we introduce a single semantic segmentation network, called DNS, for joint object detection and segmentation task. We take advantage of multi-scale deconvolution mechanism to perform real time computations. To this goal, down-scale and up-scale streams are utilized to combine the multi-scale features for the final detection and segmentation task. By using the proposed DNS, not only the tradeoff between accuracy and cost but also the balance of detection and segmentation performance are settled. Experimental results for PASCAL VOC datasets show competitive performance for joint object detection and segmentation task.

The paper sets up the two-tier screening evaluation model of potential of transnational grid interconnection that includes the mutual complementation potential model and environmental evaluation model. This two-tier screening evaluation model introduces quantitative index and applies it to the full coverage analysis and calculation of the countries along the “Belt and Road”. The combination of qualitative and quantitative analysis forms a complete evaluation system from interconnection potential calculation to electricity investment environment. The empirical analysis demonstrates the effectiveness of two-tier screening evaluation model where the analysis result may serve as the scientific reference of promoting grid interconnection of the countries along the “Belt and Road”.

A 6 degrees of freedom shimmy model for four in-wheel motors independent drive electric vehicle with independent front suspension is established, and numerical analysis and simulation are used to study the dynamic response of vehicle shimmy. The influence of electric vehicle driving system on shimmy is studied by comparing with fuelengined vehicle, and the influence of vehicle structural parameters such as the caster angle, the inclination angle of front suspensions and the centre of gravity of vehicle on shimmy are studied too. It shows that as the in-wheel motor in drive system increases the weight of wheel, the amplitude of each degree of freedom in electric vehicle are larger than in fuel-engined vehicle when vehicle shimmies. The influence of the caster angle and the centre of gravity of vehicle on vehicle shimmy is obvious, but the inclination angle of front suspension have little influence.

Nowadays, more and more applications require precise and quickly 3D recognition, such as augmented reality and robot navigation. In recent years, model-based methods can get accurate object or scene recognition, but it takes a lot of time to reconstruct the model. Therefore, we propose a fast 3D reconstruction method based on ordered images for robust and accurate 3D recognition. The proposed algorithm consists of two parts, the offline processing stage, and the online processing stage. First, in the offline processing stage, the sparse point cloud model of the scene or object is reconstructed based on the sequential images, optimized using the BA algorithm based on the local correlation frame, and then the local descriptor of the resulting model points is stored. Secondly, in the online processing stage, for each image frame of the camera video, a matching relationship between the stored point cloud and the 2D feature points on the image frame is established, based on which the pose of the camera can be solved accurately.

The multi-body dynamics model of windlass was established by RecurDyn and Pro/E in this paper, and the multi-body dynamics simulation was also conducted. According to the results of the multi-body dynamics simulation, structural static analysis on sprocket wheel in dangerous conditions were executed by ANSYS Workbench. The results showed that there are three bearing situations in the meshing transmission process of sprocket wheel and chain: Single tooth bearing, two tooth bearing and carrying equal contact force and two tooth bearing but one tooth contact force reaches the maximum value. The equivalent stress value at the contact position of sprocket wheel and chain exceeds the yield stress of the chain wheel material, but it does not cause damage to chain wheel. In addition to the contact location, the equivalent stress value of the remaining parts of sprocket wheel are in the allowable stress range of sprocket wheel material, comply with the requirement of strength design.