The accidents at nuclear power plants pose a particular threat to the population and the environment. Accidental emissions at nuclear power plants can cause long-term radioactive pollution of the environment, and the elimination of such pollution can take years. For practice, it is very important to predict the intensity and size of radioactive contamination zones for various scenarios of extreme situations at the nuclear power plants. Such a forecast will identify the most vulnerable areas and develop a response strategy to the situation that has arisen. A numerical model has been built that allows to quickly predict the scale of radioactive contamination of the territory during an emergency release at a nuclear power plant. The model is based on the application of implicit difference schemes for the numerical integration of the equation of convective-diffusion transport of impurities in the atmosphere. The developed model is characterized by the calculation speed. The results of the computational experiment are presented.

The choice of mining development strategies is based on the main indicators of mining and geological conditions that characterize mineral deposits. The purpose of the research is to argue the application of the improved Bayes criterion when choosing rational mining development strategies by taking into account the complex mining and geological conditions. The methodology of decision-making in terms of managing geotechnical systems depends on whether or not the probabilities of the conditions and dynamics of the parameters of rocks and soils are known during the development of mineral deposits, as well as the construction of infrastructure facilities. If the probabilities are unknown, then there is the problem of making decisions in the conditions of uncertainty of the initial data to assess the efficiency of the mining enterprises. And if the probabilities are known, then we are dealing with the task of making decisions in conditions of risk and assess the safety of mining operations. The improvement of the Bayes criterion enables us to determine, with an acceptable range of changes in efficiency, a strategy which provides more likely an increase in economic efficiency compared to a strategy selected using the traditional Bayes criterion.