Evaluation And Optimization Of Healthy Streets Based On Structural Equations

With the accelerated urbanization in China,the growing urban population has led to increasingly prominent health problems.Respiratory diseases caused by air pollution and safety hazards and traffic accidents caused by inadequate urban street facilities are serious threats to residents’ health.China has begun to pay attention to the role of health in urban development,and streets are closely related to residents’ lives as carriers of various urban functions.Accurate quantitative analysis of street health can provide important data to support the design and evaluation of healthy streets.In order to improve the accuracy of the analysis of healthy streets,the study addresses the problems of insufficient basis for the selection of elements and lack of scientific quantification of the evaluation system in the existing design and evaluation methods,proposes an improved quadratic factor analysis structural equation model based on research data,and uses exploratory factor analysis to select the four potential factors of "improving street quality,building a healthy environment,creating a vibrant neighborhood and bringing convenient transportation " The four potential variables to improve the health of the street are selected by exploratory factor analysis,and the health elements of the street design are analyzed and validated by combining with the relevant norms of street design in China.In turn,a healthy street evaluation model is proposed to improve the accuracy of quantitative analysis of healthy streets.The main contents and results of the study are as follows:(1)The current status of domestic and foreign research is reviewed and the current stage of healthy streets theory is summarized.The research results on healthy street research and street evaluation at home and abroad are described,the shortcomings of the evaluation methods and related designs of healthy streets in China are analyzed,and the necessity and practical significance of conducting research on healthy street system in China are argued.Different methods of quantifying elements are sorted out and summarized,and the research method of constructing a healthy street evaluation system through structural equation modeling is proposed.(2)To address the problem of insufficient theoretical support for the selection of variables before structural equation modeling assumptions,the study applied exploratory factor analysis by collecting field data from some streets in Xicheng District,Beijing,and extracted four potential variables to improve street health,namely,"improving street quality,building a healthy environment,creating a vibrant neighborhood,and bringing convenient transportation",so that healthy streets could be explained more concisely and accurately.(3)Constructing the theoretical model.Structural equations can better reflect the relationship between exogenous latent variables and endogenous latent variables,and make up for the problem of insufficient basis for calculating weights in the evaluation system composed of factors and indicators.The theoretical model of healthy streets is constructed by structural equation through the research path of "questionnaire of residents’ health intention-constructing structural equation-quantifying the influencing factors of healthy streets".The evaluation was validated by evaluating the key streets in Xicheng District.The evaluation results show that the indicators constructed in the study can quantitatively assess the impact of streets on health,visually reflect the problems of streets,and provide a basis for quantifying and explaining the selection of health street impact factors.(4)Evaluation method study for case validation.The healthy streets evaluation was used for street assessment,and the evaluation results were used as a basis to launch street optimization and compare the healthy streets before and after optimization.The results of the case show that the shortcomings of the streets reflected by the constructed healthy streets evaluation results are consistent with the problems found in the field study.The accuracy of the evaluation results is demonstrated,and it effectively proves that the quantitative evaluation of healthy streets can visually reflect the problems of streets,and then proposes a targeted street optimization strategy,which provides a reference for the design and optimization of urban streets for the purpose of improving health.