To prevent pedestrian safety accidents and optimize and help crowd security management in public places, the collection region distributions of crowd are studied at three common multidirectional flow intersections of 90°, 120° and single corridor two-way pedestrian flow using the density-based spatial clustering of applications with noise (DBSCN) algorithms at different times based on a dataset from scenario experiments. Moreover, the clustering effect and parameter difference of the two algorithms are compared. Study results show the collection region distribution patterns and characteristic changes of the crowd. The clusters cannot remain in a stable clustering state but vary dynamically in 3 subject scenarios. The proposed method can be used to identify potential locations of crowd, observe hidden danger areas, provide evacuation facilities in advance in such areas, and protect the entire section to improve the efficiency and safety of the evacuation process.

In airport engineering, an arresting system is an important safety guard for an aircraft in case it slips out of the runway. It is particularly desirable to evaluate the validity and reliability of the arresting system to ensure the safety of aircraft. In this paper, carrier-based aircraft arresting cable is the main research subject. The arresting system is divided into three parts with specific functions in the process of arresting an aircraft: blocking function, buffering function, and guiding function. Quantitative indexes are established for the three functions, and mathematical function analysis method is used to determine the quantitative values of different indexes. Using the weight, the corresponding index evaluation values are obtained. Finally, using the triangle graph theory, the trend of the arresting system functions is analyzed to determine evaluation results to comprehensively evaluate the system. Taking an arresting system in an airport as an example, data is collected and evaluated during an arresting process. The results show that using the method for model evaluation function established in this paper, the evaluation values of various functions of the arresting system in a specific arresting process can be obtained. The values for blocking function, nonbuffering function, and nonguiding function are 0.83, 0.46, and 0.64 respectively, and can be used to judge the change trend of validity and reliability of the arresting system. The research results can provide reference for functions of the arresting system evaluation.

Aiming at the systematic evaluation problem of metro transfer stations, an index evaluation system is established for the transportation function of metro transfer stations. The definition, calculation method, and scoring standard for each index are proposed. Moreover, a comprehensive index evaluation method based on the analytic hierarchy process is constructed, and the weight coefficient is discussed. A case study is conducted using seven transfer stations of Nanjing metro to verify the validity and practicality of the proposed index evaluation system. Results show that the second-level indicators can accurately reflect the current situation of the stations, and the stations can be classified based on the similarity of the index scores. Similar stations exhibit common characteristics. The index weight coefficient determined using the judgment matrix satisfies the consistency test, and the obtained first-level index score and total score can comprehensively evaluate the overall status of the station. Finally, considering the Liuzhoudonglu station as an example, an optimization of the station evaluation results is proposed, which confirms the applicability of the system.

To meet the real-time demand for passenger flow control and train dispatching in urban rail transit operation organizations, an online travel destination prediction method based on passenger origin destination(OD) spatiotemporal characteristics is proposed. First, the passenger OD spatiotemporal feature matrix is defined. Moreover, the automatic fare collection (AFC) history data of individual passengers are used as training samples, and an extraction method of passenger OD spatiotemporal features is proposed using stroke density clustering. Further, based on the matching rule analysis between the card-swiping information of passengers and their OD spatiotemporal feature matrix, the corresponding real-time destination prediction method is proposed for three matching cases. The AFC data of Nanjing rail transit are used to verify the proposed method. Results show that the proposed method is effective in the prediction accuracy of rush hours and provides stable all-day prediction, which can provide a reference for subway operations.

Subway parking lines with one train space are widely used in urban rail transit systems. However, in the process of train failure rescue , this method can accommodate only one train owing to their length limitations and will cause extra delay. Conversely, subway parking lines with two train spaces work better in train failure rescue, although higher requirements are imposed on engineering conditions and costs. This study designs eight different types of parking lines with two train spaces based on forms and setting principles of traditional parking lines with one train space, and performs a comparison analysis. Moreover, a railway simulation tool OpenTrack is used to simulate the suitability of parking lines with two train spaces during train failure rescue. Results show that each of the eight types of parking lines has its own applicative situation, and tandem parking lines exhibit better applicability among them. Furthermore, the parking lines with two train spaces can considerably reduce rescue delay time when they are set in the middle of the line away from the car depot. In the situation wherein only train failure rescue is considered, the tandem end-type parking lines are the best choice.

To ensure the safety of the surrounding environment in the excavation of foundation pits, taking the excavation of a deep foundation pit at a Xi'an subway station as an example, ABAQUS was used to establish a three-dimensional model to simulate the impact of excavation on the surrounding surface settlement and the deformation of the retaining structure. This study focused on the distribution of the surrounding surface settlement and the deformation of the retaining structure and compared the simulation results with actual monitoring data to guide site surface settlement monitoring. Analysis results show that the measured value is larger than the simulated value, but the change trend is the same. In the process of foundation pit excavation, the maximum ground settlement occurs at 11 m from the edge of the foundation pit, the maximum value being 3.29 mm; the horizontal deformation curve of the retaining structure along the excavation depth is a parabola, the maximum horizontal displacement occurs at 1/2 of the maximum excavation depth of the foundation pit, and the value is 11.05 mm. The ground settlement within 0~25 m from the long edge and 0~22 m from the short edge of the foundation pit is the largest, which should be focused on in construction monitoring.