Research On Formation Pattern Of Urban Image Based On Streetview Data

Based on the Kevin Lynch's classical urban image theory,and the perspective of the deviation between subjective perception and objective environment in real life.This dissertation concluded the formation process of urban image from three aspects: objective environment representation as the basis,environmental primary perception as the process,and subjective environmental perception as the result.According to the formation process,the central urban area of Nanjing was selected as the research scope.Meanwhile,the objective environment and subjective perception evaluation of urban streets as the research objects.In addition,street-view big data,machine learning,subjective quantitative evaluation platform and other methods was adopted to paper quantitatively analyzes the elements and representations of objective environment.The results of primary environmental perception and the evaluation of subjective environmental perception of 8720 streets in the central urban area of Nanjing,and then observes the formation mode and conditions of urban image perception from the perspective of deviation between subjective perception and objective environment.The urban image research was conducted in two aspects,on the one hand,changes the research object from a single subjective or objective dimension to a dual dimension of mutual correlation and function between main and objective.Starting from observation behavior of the objective environment and the influence of the constituent elements of the objective environment on people's vision and further perception,this paper discusses the formation process and mode of urban image from two dimensions of subjective perception and objective environment,and sums up the internal formation logic and relationship of urban image from the perspective of subjective and objective deviation.On the other hand,according to the deviation characteristics between subjective perception and objective environment in the process of urban image formation,and the functional relationship between environmental components reflected by subjective and objective deviation characteristics and subjective perception.This paper combs and summarizes the formation conditions of urban image from the perspective of subjective and objective deviation.In addition,according to the structural deviation characteristics of subjective perception and objective environment in the overall space level,this paper further summarizes the five elements of image structure from the perspective of subjective and objective deviation,including the core of image perception,nodes,corridors,circles and blind areas.Based on the research results,the main contribution of this dissertation are as follows:1.From the perspective of subjective perception and objective environment deviation,the formation mode of urban image is researched and constructed.Based on people's observation of the objective environment,this paper sums up and puts forward the formation mode of urban image perception,which consists of three stages: the objective environment of the city,the primary perception of the environment and the subjective perception of the environment,and corresponds to the different degrees of interaction between subjective perception and the objective environment.Meanwhile,by analyzing the subjective and objective differentiation and deviation characteristics among the three stages,Furthermore,this paper summarizes and puts forward the three-level deviation relationship between subjective perception and objective environment in urban image,including visual observation,information analysis and cognitive understanding,and based on this,discusses the formation conditions of urban image from the perspective of deviation between subjective perception and objective environment.2.This paper explores the quantitative analysis method of subjective and objective dimensions of urban image,through adopted the machine learning techniques and streetview big data.In this paper,street-view data is used as the unified basic data,and the full convolution neural network of machine learning is used to explore and try the doubledimensional,same-data,large-scale and randomized quantitative analysis method of subjective perception and objective environment in urban image.To a large extent,It makes up for the fact that the traditional mental map method in the field of urban image research is too subjective,the small sample size and the single-dimensional analysis method of objective environment measurement relying solely on data have explored a new analysis method and approach for analyzing the interaction between human and environment and the correlation mechanism between the two in urban image and urban planning.3.The five structural elements of urban image are re-concluded to optimize the planning strategy of urban environmental image construction.According to the urban image form mode in the three stages of objective environmental representation,environmental primary perception and subjective environmental perception,as well as the structural deviation characteristics of the image perception results in the above three stages at the overall spatial level.From the perspective of the deviation between subjective perception and objective environment,this paper sums up the structural characteristics of urban image in the overall spatial level as a five-element system composed of image perception core,nodes,corridors,circles and blind areas,which is used to optimize relevant planning practice strategies.