基于城市DEM的住宅小区地面开阔度评价

he sky view factor (SVF) has been commonly used to describe the shadow impaction of visualization or sunshine from neighborhood buildings or terrains. This paper takes SVF as a factor to indicate the quality of open space in residential area. Based on urban digital elevation model (DEM), with 9 typical residential areas in Nanjing city, this paper firstly realizes a fast algorithm of SVF based DEM. Then through the quantitative analysis of SVF in different residential areas, the open space of each residential area environment is evaluated. The Experimental results show that the residential areas of Yihelu and Gutongxiang have the best open space environment, followed by the residential areas of Minghu villa, Hujing garden and Jinmao garden. Residential areas of Changjinlou and Shanguli are the last. The study shows that SVF can be used to evaluate open space quantitatively a residential area. It can reflect the light and heat conditions such as view sight, solar radiation and ventilation comprehensively. To some extent, SVF can displays the environment quality information of a residential including the ability of micro-environment regulation, the reservation of emergency shelters venue and the quality of residential landscape.