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Objective According to GB 50157—2013 ′Code for design of metro′, the calculated platform width of metro large passenger flow station is often too narrow to afford the immense passenger flow pressure effectively. Considering passenger behavior on platforms, a new platform width calculation method is proposed to address this issue. Method The current platform width calculation methods are introduced, and their deviations from actual passenger flow at large passenger flow stations are analyzed. Two operating conditions of train yet to arrive at station and train already in station are defined, and a platform width calculation method for large passenger flow station is proposed. Taking a large passenger flow station of Xi’an Metro as example, the proposed platform width calculation method is applied and demonstrated through case study calculations. Result & Conclusion Considering that peak hours at some stations may not align with city-wide peak hours, a deviation coefficient for station operation is introduced into platform width calculation formula, with the station peak hours as a calculation period to determine the platform width. For interchange stations where interference between passengers in opposite directions exists, a cross-interference coefficient is introduced. The passenger flow on platform undergoes four stages after the train arrives, with the second stage exhibiting the highest demand for platform occupancy and displaying characteristics of both stationary ′blocks′ and moving ′lines′ of passengers. Compared with platform width calculation methods in current specifications, the proposed one demonstrates better adaptability for large passenger flow stations.

A constant volume combustion chamber is employed to investigate the laminar burning characteristics of syngas. The effects of changes in diluent gas composition (CO 2 /N 2) and H 2 /CO ratio on the laminar burning velocity (S L) of syngas are decoupled and analyzed. The instability of laminar flames is analyzed using effective Lewis number, flame thickness, thermal expansion ratio, and linear stability theory. The results indicate that as the amount of diluent gas increases, thermal diffusion instability (TD) increases, while hydrodynamic instability (DL) gradually decreases. With a decrease in the H 2 /CO ratio, TD gradually decreases, and DL increases. When the diluent content is below 45%, the critical flame radius under N 2 dilution conditions exceeds that under CO 2 dilution conditions. Above 45%, the situation reverses. As the H 2 /CO ratio decreases, the critical flame radius gradually increases. When the H 2 content is high, the critical flame radius under N 2 dilution conditions is larger. • Comprehensive analysis of the impact of diluent content and H 2 /CO ratio. • Decoupling analyzes the dilution, thermal, and chemical effects of CO 2. • Decoupling analyzes the chemical and physical effects of changing the H 2 /CO ratio. • The spherical flame instability is analyzed with linear stability theory. • Analyzing the instability range of flames by incorporating critical radius. [ABSTRACT FROM AUTHOR]

This article investigates the impact of H 2 and O 2 enrichment on the laminar burning velocity (S L) of syngas in a constant-volume combustion chamber. By analyzing changes in both chemical and thermal effects, it examines the impact of variations in H 2 and O 2 content on the S L independently. Furthermore, this article investigates the pressure variations of spherical expanding flames, flame instability, and the formation of mixed fuel NO. Results show increased H 2 and O 2 content enhance S L , with O 2 addition leading to a linear increase. H 2 affects thermal-diffusive instability differently in lean and rich fuel regions, while increasing O 2 content mitigates it. The synergistic influence of flame thickness and thermal expansion ratio amplifies fluid dynamic instability with higher H 2 and O 2 content. O 2 addition is more effective in promoting the rate of production for thermal NO and H 2 addition is more effective in promoting the rate of production for non-thermal NO. • The influence of H 2 and O 2 enrichment on combustion is analyzed. • The change of laminar combustion pressure is analyzed. • Decoupling analysis of the influence of the virtual gas method on H 2 and O 2. • The influence of H 2 and O 2 on the instability of spherical flame is analyzed. • The effects of H 2 and O 2 on different NO formation mechanisms are analyzed. [ABSTRACT FROM AUTHOR]

The distribution of transmission lines is complex, influenced by terrain and topography, making their maintenance and management challenging. With the advancement of global mechanization, various types of construction machinery and large‐scale mechanical equipment are continually increasing. Accidental contact of construction machinery near transmission lines poses a serious threat to the stability of the power system. Traditional drones and inspection robots face difficulties in achieving real‐time monitoring of construction machinery and equipment around transmission lines, quickly identifying potential risks. Conventional image processing techniques and convolutional neural networks struggle with effective handling of small targets and densely packed detection tasks involving multiple targets. To address these challenges, this paper proposes an intelligent detection algorithm Swin Transformer attention efficient algorithm‐you only look once (YOLO) (STAE‐YOLO). It is based on the Swin Transformer global self‐attention mechanism, cross‐channel fusion attention mechanism, enhanced small object detection framework, and a focused and efficient regression loss function. The experimental results show that the STAE‐YOLO algorithm model improved by 6.3% in mean average precision, 3.7% in precision, and 3.1% in recall compared to the baseline model. Meanwhile, deploying the window multi‐head self‐attention global self‐attention mechanism in the model can strengthen the global multi‐scale semantic information in detection. [ABSTRACT FROM AUTHOR]