Investigation and analysis of functional nuclei and its effect on the balance of spatial structure of the city. Case study : Tabriz

The aim of this research is to investigate the spatial structure of Tabriz Metropolis based on functional nuclei. The research method is descriptive-analytic research of causal-correlation type.   Data collection was done in a library method. Data includes urban activities that are extracted from the census. The number of activity indicators is 25, which is classified in five main industrial, commercial, administrative, financial, service and recreational categories.  And these are considered as metropolis functional nuclei. To analyze the distribution of functional nuclei from the kernel density estimation method, for analyzing spatial patterns from the mean center and the elliptic of the standard deviation, spatial correlation modeling of geographical weight regression and least squares regression have been used. The results of the research show that the spatial patterns of the functional nuclei are single-core. Tabriz is still far away from the formation of a multi-core metropolis and core subsidiary have not yet succeeded in attracting their activities and population. Spatial correlation results also show that there is a positive relationship between functional nuclei and population distribution and strengthening functional nuclei will focus the population, especially in the city center.