## 3 Results and Analysis
### The Trip Level
The distribution of hourly trip numbers is shown in Figure 6. In this figure, the numbers on the horizontal axis denote the starting hour. According to Figure 6, the trends (red polyline) of hourly trip numbers are quite similar for both origin and destination. Two typical peaks are observed: 8:00-9:00 and 18:00-19:00. They correspond to the two commuting peaks in the morning and evening, respectively. This indicates a high demand on bike-sharing during these periods. It is also noticeable that the trip numbers were consistently larger during the evening peak compared to the morning peak for both origin and destination, indicating a greater demand for bike-sharing after work. Additionally,  
Figure 5: The distribution of trip numbers under four different statistical measures: (**a**) maximum, (**b**) average, (**c**) median, and (**d**) minimum. the hourly trip numbers in the evening (18:00-24:00) were larger than those in the early morning (0:00-5:00) for both origin and destination. This indicates that the most bike-sharing citizens engage in activities (e.g., entertainment) after work in the evening, while only a minority do so in the early morning before sleep. Another distinctive finding is that the trip numbers for origin during 7:00-8:00 and 17:00-18:00 were larger than those for destination. This indicates that more trips start during these hours than end, reflecting that more citizens begin work after 8:00 and finish after 17:00, while fewer start work before 7:00 and finish after 18:00. To further explore the statistical characteristics of hourly trip numbers, we plotted the distribution of trip numbers for each day from the perspectives of both origin and destination using heatmaps, as shown in Figure 7. From Figure 7a,b, we can observe that the distributions are generally similar and align well with the trends shown in Figure 6. In both heatmaps, clear weekday-weekend patterns for hourly trip numbers are evident. Specifically, on weekdays, there are always two peaks (one in the morning and one in the evening) for both origin and destination. However, on weekends, the two-peak effect is not as pronounced. A distinctive finding on weekends is the presence of a clear peak in the evening, while the morning peak is less obvious. Additionally, the trip numbers on weekends were usually smaller than those on weekdays for both origin and destination. This indicates that bike-sharing traffic flows are more evenly distributed in the mornings on weekends but still relatively high in the evening, especially during 17:00-19:00. There are also differences in hourly trip numbers between Saturday and Sunday for both origin and destination. One noticeable difference is that the hourly trip numbers in the morning on Saturday are relatively larger than those on Sunday, indicating that more citizens prefer intra-urban mobilities on Saturdays than Sundays. These insights can provide valuable suggestions to related governmental departments and bike-sharing companies for better managing traffic flows and serving bike users. The evolutions of trip numbers across time can be explored using the CTM. Specifically, the trip numbers for each day during any time interval, from the perspectives of both origin and destination, can be derived and visualized in the CTM diagrams. These diagrams can reveal potential temporal patterns related to trip numbers. For example, the CTM diagrams of trip numbers on 15 August from the perspectives of origin and destination are shown in Figure 8. According to Figure 8, the evolution trends of trip numbers for both origin and destination are quite similar, which is consistent with the previous conclusion drawn from Figure 7. However, Figure 8 provides much more detailed information, allowing for the uncovering of additional temporal patterns. One notable pattern is that although the evening peaks for both origin and destination occurred mainly during 18:00-19:00, the red color (indicating large trip numbers) is much denser in Figure 8 than in Figure 8b.