The Research Of The Urban Air Quality Visualization System

With the development of science, the progress of the society, the environment problem has got more people’s attention. Especially in recent years the haze, which occurres in many cities such as Beijing, Tianjin, makes the problem of air pollution become the focus of attention. Since 2002,143 air quality monitoring stations have been established in 17 cities of Shandong province, and these stations have got huge amounts of monitoring data. How to display these monitoring data and find the trends, relationships and features has become the most important issue we have to solve.Visualization is a method or technology, which use the computer graphics and image processing technology to convert the data into graphics or image on the screen and to interact with it. Effective visualization method helps us to be more intuitive and convenient to observe and analyze the data, to find the characteristics and laws of the data, and to help people better understand the data and make effective decisions. Through the analysis we found that the air quality data is a hierarchical and time-series data. Hierarchical structure visualization and time-series data visualization have been widely studied, but there are still few combined reserch of them.By studying all kinds of hierarchical structure visualization and time-series visualization methods, we put forward three kinds of hierarchy and time series-data visualization methods, including node-link tree diagrams and histogram visualization, hyperbolic tree and time disc visualization, hierarchical tree and theme river visualization. They have their own characteristics and can effective display the hierarchy and time- series data. In these methods, through a variety of interactive technologies, the user can be easily observed the data and find the characteristics and laws of the data, such as periodic, correlation and exceptions of the data, and so on.On this basis, we established an urban air quality visualization system. First, in order to realize the usability and scalability of the system, we realized the authority management model based on RBAC in this system. We use a variety of traditional methods to display the data. We also use the three methods which we put forward to display the data and achieved good visual effect.