Automated vehicles (AVs) are rapidly evolving and have gained increasing attention from researchers due to their tremendous traffic management and safety advantages. While several studies discussed the implications of Cooperative Adaptive Cruise Control (CACC) technologies for capacity, few had a comprehensive approach to the impacts of CACC-equipped vehicles (Cooperative AVs) on motorway traffic management and sustainability. According to both NHTSA and SAE, CACC is considered level 1 automation. Nonetheless, the performance of CACC vehicles under each scenario can be demonstrative of the performance at higher automation levels. This paper evaluates the impacts of Cooperative AVs on motorway traffic capacity, speed, and ecological sustainability, comparing them against Regular Vehicles (RVs). A micro-simulation model in PTV VISSIM was developed to analyze the interaction of Cooperative AVs and RVs in interurban traffic scenarios. The study assessed the impact of Cooperative AVs on critical traffic metrics, including capacity, speed, flow, vehicle delay, and CO₂ emissions. Various penetration levels of Cooperative AVs (0%, 20%, 40%, 80%, and 100%) were evaluated in a mixed traffic environment alongside RVs. Results showed that Cooperative AVs significantly improve traffic performance. At full penetration, road capacity increased by 85%, average speed by 65%, and traffic flow by 80%. Additionally, vehicle delays were reduced by 75%, and CO₂ emissions decreased by 40%, underscoring both traffic efficiency and ecological benefits. These findings highlight the potential of Cooperative AVs to transform motorway traffic management by improving flow and sustainability. However, challenges remain, including the unpredictability of human drivers, mixed traffic complexities, and the need for advanced Vehicle-to-Everything (V2X) infrastructure. This study provides essential insights for policymakers and planners to better integrate Cooperative AVs into future transportation systems.

In order to solve the problems of many small radius curves and low decline rate of curve superelevation, causing wheel-rail noise, wheel rim abrasion, Tokyo Metro adopts SC101 type radial bogie, on ginza line 1000 series vehicles and it has been confirmed that the curve passing performance of radial bogie on standard gauge lines has been improved.

This paper aims at the development of narrow-gauge radial bogies, evaluation of its running performance on actual vehicles ,introduction to the outline of trial-produced narrow-gauge radial bogies, East-West line using the radial bogies 15000 System on-the-spot test results.Based on the above achievements,made new in Japan than in the valley line 13000 is a series of vehicles equipped with mass-produced SC103 type radial bogie.

Analyzed the fatigue crack characteristics near the safety lifting seat hole of the speed-up passenger car bogie,proposed the hypothesis that structural vibration fatigue caused by resonance phenomenon is the most important cause of crack in this part. through finite element simulation, the front 1-10 order mode shape,analyzed the measured acceleration and dynamic stress tests of each order mode frequency on the line.Obtains Equivalent Stress,Acceleration and Its Main Frequency ,and carries out comparative analysis with finite element simulation results. Based on mastering the failure mechanism of safety hanger.Optimize the structure of safety hanger and its fixing mode through structural improvement and adjustment of connection mode, and carry out line test on new structure,and evaluate its safety and economy.The research results show that:is affected by normal bus line conditions,safety boom vibration frequency(acceleration main frequency is 91.78Hz Main frequency of dynamic stress 91.00Hz and 4 Mode Frequency of Order(95.Calculated by Finite Element Method 79Hz.)The power spectral density of longitudinal acceleration of the safety boom which is close to each other and generates resonance is much larger than its transverse value and vertical value,which is consistent with the running direction of the train.Therefore,Vibration fatigue causes cracks to be generated at the edge of the safety suspension seat hole and 5mmthick gasket,is added on both sides of the bolt hole, and the safety boom is changed from a steel plate bending structure to a steel wire rope flexible structure.The equivalent stress amplitude at the bolt hole can be reduced to the greatest extent,and the fatigue damage accumulation is reduced. The improved safety boom meets 120010,000 kilometer usage requirement,and achieves better economic effect.

The main research content of this paper is an assistant decision-making system for emergency handling of traffic accidents in urban rail. The system is to further improve the ability of rail transit control departments to deal with emergencies through its design and application. The system can automatically judge the accident parameters and analyze the main information of the accident during the application process to put forward a systematic solution to traffic accidents, and thus reasonably arranging for urban rail train dispatching during the accident. Besides, combined with the train's normal operation, the system will collect train emergency prediction data during its application, and visualize the predicted information to provide references for the adjustment of emergency plans, further reducing possible hazards. Meanwhile, this article demonstrates the system's application with the combination of metro line 3, which ends with a satisfying result. It can be considered that the designed assistant decision-making system has practical value and can adjust train operation plans and predict passenger flow.

 Every year many people are fatally injured or killed on the roads. The number is still quite high, even if it is decreasing from year to year. Although there are fewer accidents on the roads since the epidemic, the number is still relatively high. To minimize the number of road accidents, it is important to understand which types of roads have the highest number of collisions and what the accident forecasts are for the coming years. The purpose of this article is to forecast the number of accidents on Polish roads according to their type. The study consisted of two parts. The first included a forecast of the number of road accidents for 2022–2031, based on an analysis of annual data from police statistics on the number of road accidents in Poland in 2000–2021. The second part of the study focused on monthly data from 2000–2021. In this case, a forecast was also set for the period from January 2022 to December 2023. The results of the study indicate that even after analyzing annual statistics, the number of incidents can be expected to stabilize in the coming years. This is mainly due to the expansion of expressways, especially highways, and the increase in traffic volume on Polish roads. It should be noted that the current epidemic is distorting the results.