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Objective Automatic train operation (ATO) can achieve train autonomic running by controlling each actuator of the train, and is of great significance to reduce the operating cost of rail transit and further ensure train operation safety. In response to the problems such as low parking precision and failure to optimize energy consumption with the single control method in the process of ATO speed following control, a strategy for ATO speed following control is proposed. Method Based on the traditional PID (proportional integral-differential) control, the proposed approach performs online turning and adjustment of PID parameters by using fuzzy controller, and designs algorithms for train precise parking and energy saving operation separately. When the train is running closer to the stopping point, the speed feedback control method based on the preset target speed will fall out of use, the acceleration required for precise parking is calculated instead, and the acceleration feedback control is performed to improve the parking precision. At the same time, an energy saving cruise condition with traction-coasting cycle during the train cruise is designed. When the train is detected to meet a certain cruise condition, the corresponding condition shall be used to optimize the overall operation energy consumption. Result & Conclusion A simulation model for the train and controller is established in MATLAB/Simulink simulation software. The proposed method and model are verified to be effective by comparing the performance indicators such as precise parking and energy saving under PID control and fuzzy adaptive PID control.

In this paper, three realistic high-rise residential districts in Jinan are selected.to study the relationship between the internal morphology and ventilation performance. The typical positions are tested on the basis of CFD simulation and field measurement. Result shows that it is effective to improve the residential district ventilation efficiency by avoiding the building of the matrix arrangement. Furthermore, the vegetation as an important factor in the study of residential district is significant part of the wind environment which should be taken into account. [ABSTRACT FROM AUTHOR]

Correlation research on urban space and pedestrian–level wind (PLW) environments is helpful for improving the wind comfort in complex urban space. It could also be significant for building and urban design. Correlation research is usually carried out in a space with clear urban spatial characteristics, so it is necessary to define the space first. In this paper, a typical urban area in Nanjing, China, is selected as the research object, and a spatial partition method is used to divide the real complex urban space into subspaces. The urban spatial characteristics of such subspaces are quantified using three urban spatial indices: openness (O), area (A), and shape (S). By comparing the quantitative results, 24 (12 pairs) subspaces with prominent urban spatial indices are selected as the correlation research cases. The 24 subspaces also provide a reference for the layout of the measurement points in a wind tunnel experiment. This is a new arrangement for locating the measurement points of a wind tunnel for correlation research. In the experiment, 45 measurement points are located, and the mean wind velocity of four different wind directions at 45 measurement points is experimented. The results clearly show that, when the experimental conditions are the same, the changes of mean wind velocity ratio ( U R ¯ ) of 24 (12pairs) subspaces under the four experimental wind directions are close. The U R ¯ s of the subspaces are not significantly affected by the wind direction, which is affected more by the subspaces' spatial characteristics. When making the correlation analysis between mean wind speed ratio and spatial characteristics' indices, a direct numerical comparison was not able to find a correlation. By comparing the difference values of mean wind speed (△ U R ¯ ) and indices between each pair of subspaces, the correlation between U R ¯ and openness of subspaces were found. Limited by spatial partition method, the correlation between U R ¯ and the other indices was not obvious. [ABSTRACT FROM AUTHOR]