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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.

Since the industrial revolution, human dependence on fossil fuels has resulted in increasingly severe atmospheric carbon dioxide (CO2) emissions. Electrocatalytic CO2 RR has attracted much attention because of its many advantages, such as mild reaction conditions, controllable reaction rate, low cost and scalable electrolyzer.[7] More importantly, electrocatalytic CO2 RR can control the selective generation of target products by rationally adjusting the reaction potential, electrolyte and catalyst species. However, the CO2 molecular structure is stable, and obtaining the key CO2 -based anionic intermediate CO2– from activated CO2 molecules requires overcoming a huge energy barrier. Copper (Cu) catalysts are the only monometallic catalysts to date that can form two-carbon (C2) products, which establishes their special position in the field. However, the poor selectivity of Cu for a particular product has led to a wide distribution of reduction products, covering the range from carbon monoxide (CO), a reduction product at 2e-, to ethanol (C H25 OH), a reduction product at 12e-. Meanwhile, Cu catalysts are generally less stable, which can seriously affect their commercialization. Currently, in order to obtain highly selective C2+ products (mainly ethylene and ethanol), [16]this article reviews the various methods developed by different scholars in China and abroad to modify Cu catalysts. Finally, this article suggests ways to improve the performance of Cu-based catalysts to enhance the Faraday efficiency of the C2 product from the electroreduction of C02 and gives an outlook on the future direction of Cu-based catalysts.[19]

The utilization of outdoor spaces is affected by their thermal environment. Wind, which determines the convective and evaporative heat loss from the human body, is one of the most influencing factors of thermal comfort. In the prevailing outdoor thermal comfort models, the convective heat transfer coefficients were pre-measured on a thermal manikin in a wind tunnel, where the wind speed was mostly stable. However, field measurements suggested that a typical outdoor wind process over complex terrains, like urban landscapes, are generally non-stationary. There is no experimental data on how the misrepresentation of wind may affect the convective heat transfer prediction for outdoor thermal comfort prediction. This study simulates urban pedestrian-level wind patterns in a wind tunnel by employing active and passive turbulence generators. Results show the turbulence scale through an active gust generator is approximately one to two orders of magnitude larger than the turbulence scale through a passive grid system. The eddy length scale can be adjusted through the rotation speed of the shutters. This opens the possibility of performing studies on measuring convective heat transfer coefficient under unsteady wind conditions, similar to the real outdoor environments.