Urban Semiotic Structure Reappraisal: A Representation of Perceptual Landmarks Appraisal Process (Case Study: Sadra New Town)

The conscious and purposeful design of the city structure, and in particular, the symbolic structure of the city, plays an essential role in improving the public realm quality. A set of symbolic elements is necessary to achieve such a structure, arranged in an interconnected network. This study is applied according to its main objectives and has a descriptive-analytical nature. In this research, the symbolic structure of the city has been analyzed from both citizens' and experts' perspectives. Considering the importance of signs in the spatio-physical cohesion and the integrated perception of the city structure, this study intends to explain the visual system of Sadra New Town by emphasizing the semiotic structure and the citizens' perception and mental maps. For this purpose, after selecting 90 citizens, the research team captured their mental map with the help of symbolic elements and landmark recognition in 3 stages. Following this stage, an integrated perceptual map was produced by projecting and overlaying the mental maps using GIS Software. Then, to apprehend the semiotic structure of the New Town, the elements present in the citizens' mental maps were ranked using the AHP method. It was determined that visual, perceptual, functional, and structural landmarks are among the priorities selected by the experts, respectively. The rankings were analyzed using the SAW method to assess the quality of the individuals' mental maps elements concerning the sub-criteria of each landmark. In this way, the final score of each landmark, path, and node was calculated and classified in good, medium, and poor spectroscopy. In this way, according to the analysis of the mental maps focusing on the semiotic structure of Sadra New Town, it is clear that city landmarks, visual qualities, main entrance, and the entrance of distinctive avenues, public spaces, and paths are all crucial elements in the citizens' perceptual map. These elements are components of the urban visual system with a physical-visual aspect. According to their specific characteristics, each of them can establish their position in people's minds.