## 3 Methods and Analysis
When the ratio is less than 0.5, people tend to feel that the street is spacious; when \(H/W>1\), people prone to feel intimate as the ratio increases; when \(H/W=1\), a symmetrical feeling between height and width is perceived. However, the architectural design application must be considered when defining \(H/W\). The streets of some Italian medieval cities had \(H/W\approx 2\), where the narrow streets formed a new scenery; in the Renaissance, to improve the order and aesthetic effects of urban streets, it was generally believed that streets with equal height and width would be ideal; however, in the Baroque period, to pursue magnificent effects, the width of many streets were constructed as twice the building height such that the spatial composition of the buildings can be fully appreciated. The Qilou streets in Nanning exhibit a style that combines traditional architecture with modern commerce. If the street height-to-width ratio is excessively large, then the architectural pattern will not be beautiful enough. Meanwhile, the commercial demand requires the height-to-width ratio to be not too small. Hence, \(H/W\approx 1\) is appropriate. Accurate radiation calculations in  
Figure 8: Sunshine analysis with different street orientations: (**a**) street orientation rotated 30\({}^{\circ}\) clockwise; (**b**) street orientation rotated 60\({}^{\circ}\) clockwise. Figure 6: Building level distributions in Qilou streets area. Figure 7: Sunshine analysis with different heights: (**a**) 2/3 of set value; (**b**) set value; (**c**) 1.5 times of set value. micro-environments and small-scale spaces such as urban blocks must be performed based on topography while considering the occlusion between buildings. Sunshine simulations must consider both model and environmental parameters. The model information is listed in Table 1.  
Meteorological parameter models such as the sunshine-hours model are primarily adopted to calculate the amount of radiation [18]. The data of the model's environment parameters such as the sunshine height, date, duration, standard, and precision were obtained from the \"Technical Rules for Green Building Evaluation\", [33] as shown in Table 2.  
Based on the abovementioned parameter conditions, 180 sets of data were obtained. The points along the central line of Qilou street were used as the sunshine data log point. The statistical data under various conditions for sunshine hours, height-to-width ratio, and angle were acquired. The results are shown in Figure 9. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Model Parameters** & **Value** & **Remarks** \\ \hline Street orientation & 0\({}^{\circ}\)\(\sim\)90\({}^{\circ}\) & \
\begin{tabular}{c} Setting the east-west direction as the initial value and 5\({}^{\circ}\) as the step size, shift to 90\({}^{\circ}\) northward \\ \end{tabular} \\ \hline Street width & 10 m & - \\ \hline Street length & 100 m & - \\ \hline Level height of buildings & 3.3 m & - \\ \hline Number of levels of buildings & 1–10 stories &
\begin{tabular}{c} Setting 1 as the initial value and 1 as the step size, increase to 10 levels \\ \end{tabular} \\ \hline Building width & 15 m & - \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Parameters of sunshine model of Nanning commercial streets with arcades. \begin{table}
\begin{tabular}{c c c} \hline \hline
**Environmental Element** & **Value** & **Remarks** \\ \hline Sunshine height & 0 m & - \\ \hline Sunshine location & Nanning & - \\ \hline Sunshine date & 22 June & - \\ \hline Sunshine hours & 8 h & 8: 00–16: 00 \\ \hline Sunshine standard & National standard & - \\ \hline Sunshine precision & Minute & - \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Sunshine environment parameters of commercial Qilou streets in Nanning. Figure 9: Relationship among height to width ratio, sunshine hours and street orientation in Qilou street area. The relationship between height-to-width ratio and sunshine hours under different orientations was analyzed.