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[Objective] In the new round of metro politan rail transit integration construction, enhancing train through-operation is crucial for reducing passenger interchange time. Cross-system intercity railway through-operation requires efficient train operation and scheduling management, and unified management of electronic map basic data for different lines is the key. [Method] Based on the practical demand for unified management of regional multi-system line electronic map data, the current application status of electronic maps in CBTC (communication-based train control) and CTCS (China train control system) systems is investigated. The differences in information content, acquisition methods, and transmission media of electronic maps for different signaling systems are comparatively analyzed. A regional rail transit line data management system based on a three-tier architecture comprising a regional center, local control platforms, and local workstations is proposed. Additionally, the data storage structure, data downloading method, and platform software features of the system are detailed. [Result & Conclusion] Establishing a unified management system for electronic map basic data of different lines within a region can better serve the comprehensive development of regional rail transit data synthesis, resource sharing, and management-control integration, which ensures integrated linkage command of regional rail transit, forms a multi-tiered comprehensive transportation system, and facilitates the high-quality development of regional rail transit integration in megapolitan areas.

In order to understand the mechanism of air flooding shale oil, an online physical simulation method for enhanced shale oil recovery by air injection was established by integrating CT scanning and nuclear magnetic resonance (NMR). The development effect of shale oil by air flooding under different depletion pressures, the micro-production characteristics of pore throats with different sizes and the mechanism of shale oil recovery by air flooding were analyzed. The effects of air oxygen content, permeability, gas injection pressure, and fractures on the air flooding effect in shale and crude oil production in pores with different sizes were analyzed. The recovery of shale oil can be greatly improved by injecting air into the depleted shale reservoir, but the oil displacement efficiency and the production degree of different levels of pore throats vary with the injection timing. The higher the air oxygen content and the stronger the low-temperature oxidation, the higher the production degree of pores with different sizes and the higher the shale oil recovery. The higher the permeability and the better the pore throat connectivity, the stronger the fluid flow capacity and the higher the shale oil recovery. As the injection pressure increases, the lower limit of the production degree of pore throats decreases, but gas channeling may occur to cause a premature breakthrough; as a result, the recovery increases and then decreases. Fractures can effectively increase the contact area between gas and crude oil, and increase the air sweep coefficient and matrix oil drainage area by supplying oil to fractures through the matrix, which means that a proper fracturing before air injection can help to improve the oil displacement effect under a reasonable production pressure difference.

In order to optimize the distribution of the urban emergency rescue vehicles and achieve the rapid response of the traffic accident, the distribution of multi-emergency rescue vehicles for the minimum rescue time is studied. According to the coverage control and the influence of traffic congestion for rescue time, the main research contents are as follows: analysis of the overall time consumption on the target area, establishment of the optimization model which considers the responsible area and the driving constraints of each vehicle for rescue time consumption. In details, for the division problem of responsible area of emergency rescue vehicle, the responsible area of each vehicle is calculated by using Voronoi region allocation principle and taking the driving time of vehicle to any point in urban road networks as evaluation index. Then, in consideration of the driving constraints in urban road networks, the constraints in the optimization model is clarified further on the premise of analyzing the vehicle kinematic characteristics. Finally, the optimal distribution position of multi-emergency rescue vehicles in the target area and the corresponding responsible area are calculated by gradient descent. The results show that the vehicle can converge to the optimal distribution position from any position in the target city, and the traffic accidents in responsible area can be timely response.

Aiming at the problem that is difficult to extract the fault features of gears under variable working and strong noise conditions，a fault diagnosis method based on adaptive time-varying filtering（ATF） and angle domain synchronous average（ASAD） is proposed. By combining ASAD and ATF，the signal after noise reduction is analyzed by order spectrum，and the local fault of gear can be diagnosed by modulation side frequency band in order spectrum. The simulation data and the data analysis of the variable speed gearbox test bench show that the proposed method has a good signal analysis adaptability for the gear vibration signals under the variable speed condition，and can not only filter out noise interference well，improve the noise suppression effect in the pass band，but also effectively highlight the gear fault characteristics under the variable speed condition.

Objective To investigate the age-related changes of the mandibular third molar root pulp visibility in individuals in East China, and to explore the feasibility of applying this method to determine whether an individual is 18 years or older. Methods A total of 1 280 oral panoramic images were collected from the 15-30 years old East China population, and the mandibular third molar root pulp visibility in all oral panoramic images was evaluated using OLZE 0-3 four-stage method, and the age distribution of the samples at each stage was analyzed using descriptive statistics. Results Stages 0, 1, 2 and 3 first appeared in 16.88, 19.18, 21.91 and 25.44 years for males and in 17.47, 20.91, 22.01 and 26.01 years for females. In all samples, individuals at stages 1 to 3 were over 18 years old. Conclusion It is feasible to determine whether an individual in East China is 18 years or older based on the mandibular third molar root pulp visibility on oral panoramic images.

The change of war mode has led to the emergence of new threat targets. In recent years, with the development of technologies, air-space hypersonic flight technology continues to mature and form equipment. It is necessary to develop missile weapons and equipments to intercept and attack the hypersonic vehicles. For fast flight speed and strong maneuverability of air-to-air missile, it has the advantages of free ballistic design and clean detection background for air-space hypersonic attack and defense confrontation by using air-to-air missile. This paper expounds the development status of air-to-space attack and defense confrontation abroad, and analyzes some difficulties of air-to-air missile such as the launch mode and the thermal protection, etc, and puts forward seven key technologies that need to be studied, so as to provide reference for the development of new air-to-space attack and defense confrontation.