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One of the issues facing today's cities in Iran is the issue of maintaining and upgrading existing streets. The way of managing theses streets and dealing with them has caused various problems in different aspects of cities. The purpose of this research is investigating the principles of maintenance and promotion of urban streets with a focus on Islamic teachings and Iranian culture. This research also explains some ways to improve the quality of urban streets using Islamic teachings and Iranian culture. Gathering information was done through observation, field study and documentary studies. Using content analysis methods, documenting and graphical analysis, information and data were analyzed. The quality of the cities depends on the quality of the streets and the quality of the streets is also based on the details of the streets. After designing and constructing urban streets, they need attention, maintenance and promotion in order to be always attractive and desirable for citizens. The results of this study indicate neglecting the indigenous material, art, culture, religion, needs and interests of citizens which has led to the construction of unqualified urban spaces in the metropolitan areas of today's Iranian cities. This research did not seek to provide a template for urban streets designing, but it is in direction of developing principles of planning and designing urban streets based on Islamic teachings and Iranian culture. In addition to having appearances according to Islamic teachings and Iranian culture, desirable street for Iranian citizens should also be Islamic and Iranian internally. With Just the correctness of appearances it can be said that only hypocrisy is obtained, but with internal reforming, honesty can be created in urban spaces.

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There are several limiting factors to the development of cities. These factors lead cities to develop in certain directions. Air pollution as a major problem of metropolises can itself be considered as a limiting factor of urban development by urban decision makers. 4 relatively large power plants are operating in Mashhad. There are currently two power plants in the east of the city and two in the west of Mashhad. Most of the fuel in these power plants is gasoline and natural gas. Modeling the air pollutant emissions of these power plants and identifying the pattern of pollutant emissions across the city can play a key role in the quality of life and health of approximately 3.5 million Mashhad residents. The outputs of this model can also be used as an effective parameter in estimating the urban development model. In this study, the emission of NOX, CO and 10PM pollutants was modeled and evaluated using AERMOD software in Mashhad. Using Arc GIS software, the population affected by these air pollutants was determined by one year solar time, the concentration of pollutants in different areas of the city and the area affected by the pollution concentration range was determined.