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Bolted joints are the most common type of mechanical connections, and improving the anti-loosening performance of bolts for the reliable performance of mechanical and building structures is highly significant.

Because of the lack of sufficient theoretical basis for the evaluation and design of anti-loosening bolts, a quantitative evaluation model exhibiting the following two evaluation criteria for anti-loosening bolts is introduced: bolt rotation angular acceleration criterion and critical transverse load criterion. Based on the relationship among bolt tension, transverse load and bolt rotation angular acceleration, a critical transverse load calculation model is put forward, and the mechanism by which the critical transverse load increases with the increase of bolt tension is revealed.

Based on the above model, a new type of anti-loosening bolt is designed, which generates additional bolt tension when the transverse load increases, and then improves the critical transverse load of the bolt. The effectiveness of the new type of anti-loosening bolt is verified by theoretical calculations and experiments.

The proposed model and method set a preliminary theoretical foundation for the evaluation of bolt anti-loosening performance and the design of a new anti-loosening bolt.

The purpose of this paper is to design a third-order linear active disturbance rejection controller (LADRC) to improve the response characteristics and robustness of the electrohydraulic servo system.

The LADRC was designed by replacing the nonlinear functions in each part of ADRC with linear functions or linear combinations, and the parameters of each part of the LADRC were connected with their bandwidth through the pole configuration method to reduce the required tuning parameters, and used an improved grey wolf optimizer to tune the LADRC parameters.

The anti-interference control simulation and experiment on the LADRC, ADRC and proportion integration differentiation (PID) were carried out to test the robustness, anti-interference ability and superiority of the designed LADRC. The simulation and experiment results showed that the LADRC control and anti-interference control had excellent performance, and because of its simple structure and fewer parameters, LADRC was easier to implement and had a better control effect and anti-interference.

For the problems of parameter perturbation, unknown interference and inaccurate model in the electrohydraulic position servo system, the designed third-order LADRC has good tracking accuracy and anti-interference, has few parameters and is conducive to promotion.

On the basis of the research data of 120 enterprises from 10 development zones in Gansu Province, we conducted regional planning research combining enterprise architecture with ecological green space environment system. We determined that the largest part of the green space pattern is the “other green space,” which mainly depends on the formation of super large plantation. However, this part is consistently decreasing in recent years. Affiliated green space became the largest in the green space patterns because of the high degree of vertical greening of the enterprise architecture in the development zones. The high fragmentation of the affiliated green space also leads to the high fragmentation of the entire green space of the development zone. In future regional planning of development zones, future planning of the green space can take the current green space as the basis, use the road green space and green corridors nearby waters as the basic framework to connect other patterns of green space, and form a ring-shaped enclosure, reticular structure, and wedge-shaped and dotted supplemented regional pattern. Meanwhile, the road green space system can be reasonably arranged by setting new green space spots at road intersections and key strategic positions to connect the isolated green space patches and improve the connectivity of the green space.

Village-level archives are the most basic construction unit of rural archives in China, yet the village-level archival work is the most poorly delivered. However, the evolution of the laws and rules on village-level archival work in recent years signal that Chinese village-level archival work has stepped into a new era. In this context, this article aims to review the detailed history of village-level archival legislation, examine the legislation’ implementation effect and discuss the existing problems with a view to providing improvement measures.

A historical research method is used to review the legislation’ history, and the analysis involving the implementation effect is mainly based on literature of two kinds, which are investigation reports on sample villages’ archival work carried out by scholars, and summary reports and work schemes on national or local village-level archival work given by the archival management or administrative management departments at various level.

At first, China only issued non-legal administrative orders toward village-level archival work. Later, some regions issued local rules, and finally the national rules and even Archives Law with relevant provisions were promulgated. However, their implementation faced two fundamental problems; firstly the insufficient endogenous demand for archival work in some villages, and secondly the mechanism problem involving village level archives management. The countermeasures are also discussed building on these two points.

This is the first article to systematically combine a review of the history of Chinese village-level archival legislation and in addition to examine their implementation effect including analyzing the existing problems from the macro level.