Тhe mathematical model of demographic processes research in the form of a five-phase system of mass service

The mathematical model of the change process of a demographic situation in the form of five-phase independent system of mass service with unlimited number of devices is presented. The research is carried out by the method of moments. First and second moments of number of the applications served in system are found. The developed model and the method are applied to forecasting process of demographic changes in the Russian Federation.