Urban blue space offers substantial health benefits by encouraging population physical activity. Despite much evidence on the nature-health nexus, the relationship between blue space and recreational exercises remains under-studied, limiting the realisation of health benefits in blue space design. Using crowdsourced data, including volunteered geographic information and street view image data, this study investigates the associations of blue space quality with recreational running and cycling in Rotterdam, the Netherlands. Results show that recreational exercise levels on street segments vary based on the blue space type and design. Compared to inland canals and rivers, small-scale recreational waterbodies are more conducive to running but not cycling, while both activities tend to cluster around the Nieuwe Maas River. Interestingly, the Water View Index shows a general negative association with both activities after adjusting for the blue space type. Besides the waterbody characteristics, eye-level environmental factors, including higher Green View Index, lower building density, more diverse land use, greater connected street network and fewer traffic elements, are associated with more running and cycling exercises. Results for visual complexity and neighbourhood population composition are mixed depending on the exercise type. These findings are further translated into spatial design patterns for developing exercise-supportive and health-promoting blue spaces.@en

Commercial complexes integrate various business formats, and a fire outbreak can lead to widespread, continuous, and chain-reaction social disturbances, including severe casualties, economic losses, and social impacts. To deeply explore the characteristics and influencing factors of fire accidents in urban commercial complexes in China, this study first analyzed fire accident cases in commercial complexes that occurred from 2002 to 2022. Using mathematical statistics, the analysis examined the year and month of the accidents, their severity, and their causes to identify key risk factors associated with fire hazards in urban commercial complexes. Subsequently, based on the WSR methodology, an index system for assessing the influencing factors of fire accidents in commercial complexes was constructed, encompassing four aspects: personnel, equipment, environment, and management, including 11 cause indicators and 9 outcome indicators. Then, the Decision Experiment and Evaluation Laboratory Method (DEMATEL) was used to quantitatively analyze the relationships among influencing factors, combined with Interpretative Structural Modeling (ISM) to perform a hierarchical categorization of the factors and identify those critically influencing commercial complex fires. This research indicates that critical influencing factors include inadequate regulations, insufficient fire safety inspections, inadequate safety training, careless use of fire during operations, inadequate government supervision, illegal renovations, unimplemented corporate fire safety responsibilities, and poor routine maintenance and management. These results provide a theoretical reference for effectively preventing and controlling fires in commercial complexes.@en