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This paper analyzes the outstanding technical weaknesses in the intelligent construction of coal mines in China. This paper puts forward 12 innovative research and development directions, including intelligent system design, information infrastructure, intelligent geological support, intelligent mining and transportation, intelligent safety prediction and early warning, intelligent power supply and intelligent water affairs, intelligent washing, intelligent parks, intelligent open-pit coal mines, intelligent well construction, intelligent equipment and robots, and emergency rescue and supervision. 46 coal mine intelligent innovation teams have been established, forming the strongest team of coal mine intelligent innovation. The target collaboration, organization collaboration, knowledge collaboration and business collaboration models of the innovation chain and industry chain are established. Relying on 136 provincial experimental platforms, this study takes the lead in obtaining a number of innovative achievements in the important technical direction of the intelligent coal mine. This paper provides technical support for the construction of intelligent coal mine in our country. This study puts forward 9 key breakthrough directions to continuously promote the intelligent construction of coal mines and improve the technical equipment support capacity. It is suggested to continuously build the intelligent support technology system of coal mine, accelerate the construction of the intelligent technology standard system of coal mine and the construction benefit evaluation system, and accelerate the research and application of the intelligent 'MineCloud' of coal mine. It is suggested to develop complete sets of intelligent mining process equipment for large mining height caving coal, strengthen the research and development of intelligent fast heading technology and equipment, and develop highly reliable and stable intelligent mine sensors. It is suggested to accelerate the research and development of key technologies of coal mine robot cluster, accelerate the construction of intelligent washing complete equipment and process package development, and strengthen the advanced and mature intelligent process and the stability and high reliability of core equipment in open-pit coal mines.

The hydraulic support automatic follow-up control should have the performance of high support, fast support moving, large moving distance, etc. Among these performance, under the premise of ensuring stope safety, shortening the time of working face empty roof is an extremely critical issue. However, the current hydraulic support automatic follow-up control has problems such as long action time, lower efficiency than manual operation, control parameters set by experience and other problems, resulting in the slow moving speed of the fully mechanized working face, and poor matching of hydraulic system pressure and flow. In order to reduce the action time of the hydraulic support and improve the moving speed of the fully mechanized working face, the flow-pressure mathematical model of the hydraulic support valve-controlled cylinder unit in hydraulic cylinder extension action transient process is established. The analysis shows that the instantaneous pressure of the hydraulic cylinder extension is mainly related to the supply and return hydraulic pressure, and has a quadratic relationship with time. Based on the above conclusions, three schemes for column fast fluid supply and return named direct supply by column liquid supply valve, two-level control + column fast liquid supply valve, and direct supply by electro-hydraulic controlled reversing valve are presented. The working principles of the three schemes are introduced in detail. The simulation models of hydraulic support based on the three schemes are established in AMESim software, and the stability and rapidity of the three schemes are compared by analyzing the transient pressure and action time of the rod cavity and rodless cavity of hydraulic cylinder when the hydraulic support executes the cycle of column lowering-support moving-column lifting under different schemes. The results show that the pressure curves of the rod cavity and rodless cavity of hydraulic cylinder are basically the same when the hydraulic support executes the cycle of column lowering-support moving-column lifting under the three schemes. It is considered that the stability of the three schemes is basically the same. The total time for the hydraulic support to perform the cycle of column lowering-support moving-column lifting under the direct supply by electro-hydraulic controlled reversing valve is the shortest, which is 935 s and is 221% shorter than the traditional scheme. Therefore, it is concluded that the direct supply scheme by electro-hydraulic controlled reversing valve is the best scheme.

Vehicles sent location information to third parties to obtain location-based services in the Internet of vehicles, which may lead to vehicle trajectory privacy leakage. To address the privacy problem, trajectory privacy protection mechanism of obfuscating paths based on vehicles cooperation was proposed. Firstly, after the vehicle trajectory entropy reaches the custom trajectory protection threshold, the overhead of paths confusion saves by reducing the number of vehicle paths confusion. Then, paths confusion algorithm was designed to increase chances of vehicle paths confusion at intersections, which can improve the degree of vehicle trajectory protection. Finally, the simulation experiment verified the validity and efficiency of the method from the trajectory entropy and trajectory tracking success rate.