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Abstract: The paper summarises damage tolerance investigations on railway rails which the authors have carried out in the context of the German–French joint project NOVUM (novel methods for quantitative prediction of rail performance at increased service loads) [Girardi L, Heyder R, Dider L, Boulanger D. IDR2-NOVUM promises lower rail maintenance costs. Railway Gazette Int 2005;(July):439–41]. The investigations include the determination of the crack driving force as a function of the various loading components a rail is subjected to and the simulation of residual lifetime. Features such as the local load input at the rail–wheel interface, dynamic effects and statistical aspects of crack resistance are explicitly taken into account. [Copyright &y& Elsevier]

The COVID-19 virus outbreak has affected most of the world in 2020. This paper deals with artificial intelligence (AI) methods that can address the problem of predicting scale, dynamics and sensitivity of the outbreak to preventive actions undertaken with a view to combatting the epidemic. In our study, we developed a cellular automata (CA) model for simulating the COVID-19 disease spreading. The enhanced infectious disease dynamics S E I R (Susceptible, Exposed, Infectious, and Recovered) model was applied to estimate the epidemic trends in Poland, France, and Spain. We introduced new parameters into the simulation framework which reflect the statistically confirmed dependencies such as age-dependent death probability, a different definition of the contact rate and enhanced parameters reflecting population mobility. To estimate key epidemiological measures and to predict possible dynamics of the disease, we juxtaposed crucial CA framework parameters to the reported COVID-19 values, e.g. length of infection, mortality rates and the reproduction number. Moreover, we used real population density and age structures of the studied epidemic populations. The model presented allows for the examination of the effectiveness of preventive actions and their impact on the spreading rate and the duration of the disease. It also shows the influence of structure and behavior of the populations studied on key epidemic parameters, such as mortality and infection rates. Although our results are critically dependent on the assumptions underpinning our model and there is considerable uncertainty associated with the outbreaks at such an early epidemic stage, the obtained simulation results seem to be in general agreement with the observed behavior of the real COVID-19 disease, and our numerical framework can be effectively used to analyze the dynamics and efficacy of epidemic containment methods. • Cellular Automata include density population of Poland, France, Spain in SEIR model. • We analyze influence of parametric adjustment for modeling pandemic prevention. • The earlier reduction of personal contacts the faster reduction of infections number. • Age dependent mortality rates are explored to reflect the real features of COVID-19. • Our approach allows for modeling of COVID-19 presumable dynamics. [ABSTRACT FROM AUTHOR]