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Metro stations have become a crucial aspect of urban rail transportation, integrating facilities, equipment and pedestrians. Impractical physical layout designs and pedestrian psychology impact the effectiveness of an evacuation during a metro fire. Prior research on emergency evacuation has overlooked the complexity of metro stations and failed to adequately consider the physical heterogeneity of stations and pedestrian psychology. Therefore, this study aims to develop a comprehensive evacuation optimization strategy for metro stations by applying the concept of design for safety (DFS) to an emergency evacuation. This approach offers novel insights into the management of complex systems in metro stations during emergencies.

Physical and social factors affecting evacuations are identified. Moreover, the social force model (SFM) is modified by combining the fire dynamics model (FDM) and considering pedestrians' impatience and panic psychology. Based on the Nanjing South Metro Station, a multiagent-based simulation (MABS) model is developed. Finally, based on DFS, optimization strategies for metro stations are suggested.

The most effective evacuation occurs when the width of the stairs is 3 meters and the transfer corridor is 14 meters. Additionally, a luggage disposal area should be set up. The exit strategy of the fewest evacuees is better than the nearest-exit strategy, and the staff in the metro station should guide pedestrians correctly.

Previous studies rarely consider metro stations as sociotechnical systems or apply DFS to proactively reduce evacuation risks. This study provides a new perspective on the evacuation framework of metro stations, which can guide the designers and managers of metro stations.

To improve the sustainable performance of the power supply chain system (PSCS), the Chinese government proposed a series of relevant policies and promoted the application of various technologies in the power industry. This study analyzes the sustainable performance and technology levels of PSCSs in various regions of China.

To quantify the technological heterogeneity between PSCSs, this study incorporates a meta-frontier into the performance evaluation model. To increase the performance of inefficient PSCSs, this study also proposes a series of performance improvement path indexes.

Empirical analysis of China's provincial PSCSs, using data from 2014 to 2017, has yielded several key findings. First, the average performance of PSCSs of all provinces in China is 0.7192, indicating that PSCSs in China have great potential for improvement. Second, independent of power generation subsystem (PGS) or power retail subsystem (PRS), regional differences affect the technological heterogeneity of PSCSs in China. Third, for PGS, the technological level of PSCSs in the eastern region displays a high level, while the management level can still be greatly improved. Fourth, only the PSCS of Beijing is best in both PGS and PRS. The two subsystems of the PSCSs in the other provinces are either insufficiently managed or technologically inadequate.

Compared with the traditional performance model, the model proposed in this study considers the technological heterogeneity between PSCSs. In addition, the path indexes proposed in this study clearly indicate an improvement direction and the specific improvement level for inefficient PSCSs.

The power industry is the pillar industry of the Chinese economy, and also a major carbon emitter. The performances of both the production and operation of the power industry are crucial for a harmonious development of society. This study proposes an improved data envelopment analysis (DEA) model to analyze the sustainable performance of China's power supply chain (PSC).

To analyze the sustainable performance of PSC systems in China's provincial regions, this study proposes a two-stage directional distance function (DDF) model. The proposed model not only considers the leader–follower game relationship between the power-generation system and the retail system, but also considers the factors that measure the sustainability level of the PSC.

The proposed model is applied to assess the sustainable performance of the PSCs of China's provincial regions. The findings are valuable and mainly include the following aspects: First, compared with other models, this study regards the intermediate variable of the power system as a freely disposable variable; therefore, the efficiency of the proposed model is more realistic. Second, the average efficiency of China's power retailing system is generally lower than the average efficiency of its power-generation system. Third, significant regional differences affect the power-generation efficiency, while the regional differences in power retail efficiency are not significant. The power-generation performances of PSCs in East China and Northeast China are generally higher than in other regions.

This study introduces the convex technique into a DEA model and thus proposes an improved two-stage DDF DEA model. In response to the game-theoretic inherent in power systems, this study also introduces the leader–follower game into the two-stage model. In addition to the theoretic novelty, all PSCs can be classified with this model. Moreover, specific recommendations for each type of PSCs are proposed based on the efficiency results, thus providing vital guidance for the practice.

Social responsibility (SR) has become critical in facilitating the sustainability of new infrastructure construction (NIC) and is also a nonnegligible aspect in its management. Although studies attempting to explore this issue from various and disparate perspectives have become increasingly popular, no consensus has yet been reached regarding what SR factors affect NIC management. This paper aims to establish an inventory of SR factors for NIC and reveal a comprehensive framework for SR of NIC (NIC-SR) management through an in-depth analysis of the relationships among factors.

This article proposes a mixed-review method that combines the preferred reporting items for systematic reviews and meta-analyses and content analysis methods as a solution.

From 62 chosen publications on NIC-SR published in peer-reviewed journals between 2010 and 2022, a total of 44 SR factors were found. These 44 SR factors were divided into 4 interconnected categories: political, ethics-environmental, legal and economic. Based on the interactions among SR factors and incorporating the impact of the four categories of SR factors on NIC management, an integrated framework from micro to macro was developed.

This paper educates researchers and practitioners about the SR factors that must be considered to improve the sustainability of NIC management and provides practical implications for architectural, engineering and construction (AEC) practices. Furthermore, it serves as an impetus for governments to improve their programs and policies and fulfill social responsibilities.

The purpose of this paper is to present a crack initiation mechanism of the external hydrogen effect on type 304 stainless steel, as well as on fatigue crack propagation in the presence of hydrogen gas.

The effects of external hydrogen on hydrogen-assisted crack initiation in type 304 stainless steel were discussed by performing fatigue crack growth rate and fatigue life tests in 5 MPa argon and hydrogen.

Hydrogen can reduce the incubation period of fatigue crack initiation of smooth fatigue specimens and greatly promote the fatigue crack growth rate during the subsequent fatigue cycle. During the fatigue cycle, hydrogen invades into matrix through the intrusion and extrusion and segregates at the boundaries of α′ martensite and austenite. As the fatigue cycle increased, hydrogen-induced cracks would initiate along the slip bands. The crack initiation progress would greatly accelerate in the presence of hydrogen.

To the best of the authors’ knowledge, this paper is an original work carried out by the authors on the hydrogen environment embrittlement of type 304 stainless steel. The effects of external hydrogen and argon were compared to provide understanding on the hydrogen-assisted crack initiation behaviors during cycle loading.