With the continuous improvement of train speed, the automatic driving of trains instead of driver driving has become the development direction of rail transit in order to realize traffic automation. The application of single modeling methods for speed control in the automatic operation of high-speed trains lacks exploration of the com-bination of train operation data information and physical model, resulting in low system modeling accuracy, which impacts the effectiveness of speed control and the operation of high-speed trains. To further increase the dynamic modeling accuracy of high-speed train operation and the high-speed train's speed control effect, a high-speed train speed control method based on hybrid modeling of mechanism and data drive is put forward. Firstly, a model of the high-speed train's mechanism was created by analyzing the train's dynamics. Secondly, the improved kernel-principal component regression algorithm was used to create a data-driven model using the actual opera-tion data of the CRH3 (China Railway High-speed 3) high-speed train from Huashan North Railway Station to Xi'an North Railway Station of "Zhengxi High-speed Railway," completing the mechanism model compensation and the error correction of the speed of the actual operation process of the high-speed train, and realizing the hybrid modeling of mechanism and data-driven. Finally, the prediction Fuzzy PID control algorithm was devel-oped based on the natural line and train characteristics to complete the train speed control simulation under the hybrid model and the mechanism model, respectively. In addition, analysis and comparison analysis were conduct-ed. The results indicate that, compared to the high-speed train speed control based on the mechanism model, the high-speed train speed control based on hybrid modeling is more accurate, with an average speed control error reduced by 69.42%. This can effectively reduce the speed control error, improve the speed control effect and oper-ation efficiency, and demonstrate the efficacy of the hybrid modeling and algorithm. The research results can provide a new ideal of multi-model fusion modeling for the dynamic modeling of high-speed train operation, further improve control objectives such as safety, comfort, and efficiency of high-speed train operation, and pro-vide a reference for automatic driving and intelligent driving of high-speed trains.
With the increasing flow of urban rail transit and the increasing scale of the road network, the operational risk of urban rail transit is also increasing. It had great significance to assess the operational safety of urban rail transit. In order to objectively evaluate the risk severity level of the urban rail transit, the author put forward a method based on combination weight and cloud model. Firstly, the risk severity evaluation index system was established. Secondly, the weight of the evaluation index was calculated by AHP method. Thirdly, the security evaluation method based on cloud model was given. Finally, the effectiveness of the method was illustrated by an example.
It is an important task to estimate a 3D bounding box from monocular images for autonomous driving. However, the monocular pictures do not have distance information, so it is difficult to acquire accurate results. For the sake of solving the trouble of low accuracy of the monocular image in 3D target detection because of lacking distance information, an improved monocular three-dimensional target detection algorithm based on GUPNet and neural network was proposed to promote the precision of target detection. First, based on the geometric method proposed by GUPNet, the depth, and uncertainty are obtained by direct regression using a neural network. According to the difference in the accuracy of the two methods, a parameter α was introduced, and their depth scores are obtained from the uncertainty. According to the depth score and parameter α, the depth obtained by the two methods is fused to get the final depth. Test results prove that the proposed algorithm promotes average detection precision of KITTI data set in simple, medium, and difficult cases.
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