## 2 Research Area and Data
### Data Sources  
Urban social vitality was derived from Baidu Heat Map information ([[https://map.baidu.com/](https://map.baidu.com/)]([https://map.baidu.com/](https://map.baidu.com/)); accessed on 16 December 2024). Prior studies have analyzed the characteristics of heat maps from Monday to Friday, revealing consistent patterns in residents' travel behaviors, which also exhibit similarity on Saturdays and Sundays [38]. To avoid the interference of holidays and other special events on social vitality, this study selected two typical dates to measure social vitality. These two dates represent normal daily activities and are not affected by any major external factors that may cause data deviation. In this way, this study aims to obtain more accurate and consistent measurement data of social vitality and more clearly reflect the daily social interactions and activities. Consequently, the Baidu Heat Maps from 14 November 2024 (a weekday), and 17 November 2024 (a weekend), were selected as data sources, focusing on a time interval from 8 a.m. to 12 p.m., with data generated hourly. To represent social vitality, this study calculated the average heat density values at 34 distinct time points. High-resolution nighttime light data from the Qingdao LuoJia1-01 remote sensing imagery ([[http://www.lmars.whu.edu.cn](http://www.lmars.whu.edu.cn)]([http://www.lmars.whu.edu.cn](http://www.lmars.whu.edu.cn)); accessed 6 January 2025) were employed to evaluate the economic vitality of the city [39]. The nearest-neighbor resampling technique was applied to the image, and the mean luminosity within the unit was calculated to represent economic vitality. The assessment of urban cultural vitality is based on data obtained from the Amap Open Platform ([[https://lbs.amap.com/](https://lbs.amap.com/)]([https://lbs.amap.com/](https://lbs.amap.com/)); accessed on 4 November 2024). This data encompasses significant cultural elements, including museums, exhibition centers, libraries, concert halls, theaters and art galleries. The density of Points of Interest (POIs) is employed as a metric to evaluate cultural vitality [40]. Drawing upon variables established in prior research [11; 28; 41; 42; 43] as well as the 5D framework of the urban built environment developed by [PERSON] [30] and [PERSON] [31], this study evaluates the urban built environment through five key dimensions (Table 1). Basic geographic data, including administrative boundaries and water areas, are sourced from the Resources and Environmental Science and Data Platform of the Chinese Academy of Sciences ([[https://www.resdc.cn/](https://www.resdc.cn/)]([https://www.resdc.cn/](https://www.resdc.cn/)); accessed on 4 November 2024). Vector data for buildings  
Figure 1: Location of the study area. and various Points of Interest (POIs), such as bus stops, subway stations and urban center points, are obtained from the Open Platform of AutoNavi Maps ([[https://lbs.amap.com/](https://lbs.amap.com/)]([https://lbs.amap.com/](https://lbs.amap.com/))) accessed on 4 November 2024). Urban road network data is acquired from the vector layers provided by OpenStreetMap (OSM) ([[https://download.geofabrik.de/](https://download.geofabrik.de/)]([https://download.geofabrik.de/](https://download.geofabrik.de/)); accessed on 4 November 2024).