- The roadside accident frequency is higher in mountainous area highway,this is concerned with lacking protection facilities.
- The identification and improvement of black-spot, as an important task of traffic safety management, are very effect measures to reduce the traffic accident frequency.
- Stand tanks, spherical vessels and cylinder vessels, reactors are special facilities which are widely used in national produce, also, they have high accident frequency.
- The accident frequency changes at different time and areas in highways, and the high risk group is young and adult males in happening probability, but the older injured has a higher mortality.
- In this paper,the characteristics and setting up procedures of GM(1,1) dynamic prediction model in gray theory is briefly described,as well as its application in prediction of accident frequency.