This paper studies the modeling theories and simulation methods for railway transportation system. The railway transportation system is a typical temporal-spatial dynamic system. Recently the method with temporal-spatial computation characteristics, Cellular Automata, is often used for road traffic flow research, but it’s homogeneity restricting make it impossible to modeling railway transporta...

Railway maintenance planners require a predictive model that can assess the railway track geometry degradation. The present paper uses a hierarchical Bayesian model as a tool to model the main two quality indicators related to railway track geometry degradation: the standard deviation of longitudinal level defects and the standard deviation of horizontal alignment defects. Hierarchical Bayesian...

Railway ballast tamping operation is employed in order to restore the geometry of railway track distorted by train traffics. In this paper, based on analysis of tamping principle, the discrete element analysis model of railway ballast is created using the discrete element method, numerical simulations are performed to study the change of railway ballast compactness during tamping process. This ...

Fluid drops tend to be spheres--a shape that minimizes surface energy. In thunderstorm clouds, drops can become unstable and emit thin jets when charged beyond certain limits. The instability of electrified drops in gases and liquids has been widely studied and used in applications including ink-jet printing, electrospinning nanofibers, microfluidics and electrospray ionization. Here we report ...

White-tailed deer (Odocoileus virginianus) may cause more damage than any other species of wildlife. These damages include crop loss, automobile and aviation collisions, disease transmission, environmental degradation, and destruction of ornamental plantings. One practical method of controlling deer damage is the use of exclusionary fences. The relatively high cost of labor and materials requir...

New railway legislation in Sweden has increased the need for transparent access charges on the Swedish railway network. We estimate cost functions for infrastructure operation, maintenance and renewal in the Swedish national railway network, using unobserved effects models and calculate marginal costs for railway infrastructure wear and tear. We find evidence of unobserved fixed effects at a tr...