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In this paper, we consider a numerical scheme to solve first order Hamilton-Jacobi (HJ) equations posed on a junction. The main mathematical properties of the scheme are first recalled and then we give a traffic flow interpretation of the key elements. The scheme formulation is also adapted to compute the vehicles densities on a junction. The equivalent scheme for densities recovers the well-known Godunov scheme outside the junction point. We give two numerical illustrations for a merge and a diverge which are the two main types of traffic junctions. Some extensions to the junction model are finally discussed. [ABSTRACT FROM AUTHOR]

How to alleviate the damages of cascading failures triggered by the overload of edges/nodes is common in complex networks. To describe the whole cascading failures process from edges overloading to nodes malfunctioning and the dynamic spanning clustering with the evolvement of traffic flow, we propose a capacity assignment model by introducing an equilibrium assignment rule of flow in artificially created scale-free traffic networks. Additionally, the capacity update rule of node is given in this paper. We show that a single failed edge may undergo the cascading failures of nodes, and a small failure has the potential to trigger a global cascade. It is suggested that enhancing the capacity of node is particularly important for the design of any complex network to defense the cascading failures. Meanwhile, it has very important theoretical significance and practical application worthiness in the development of effective methods to alleviate the damage of one or some failed edges/nodes. [ABSTRACT FROM AUTHOR]

Objective. To assess fitness to drive among drivers with treated obstructive sleep apnea syndrome. Methods. A total of 5234 drivers who attended two Spanish Medical Driver Test Centers for assessment of their fitness to drive prior to renewing or issuing their driving license were included in the study. Information regarding sociodemographic aspects, patterns of driving, medical condition, medication use, and patterns of alcohol consumption was recorded. Results. Eleven out of 5234 drivers (0.2%) suffered from obstructive sleep apnea syndrome, all of them being treated with continuous positive airway pressure, and they were found fit to drive with restrictions. Conclusions. A lower than expected prevalence of patients with obstructive sleep apnea syndrome was found among drivers undergoing fitness to drive assessment. Suffering from obstructive sleep apnea syndrome does not prevent driving as long as the patient is undergoing adequately controlled treatment. [ABSTRACT FROM AUTHOR]

Stability analysis of a single-lane microscopic car-following model is studied analytically from the perspective of delayed reactions of human drivers. In the literature, the delayed reactions of the drivers are modeled with discrete delays, which assume that drivers make their control decisions based on the stimuli they receive from a point of time in the history. We improve this model by introducing a distribution of delays, which assumes that the control actions are based on information distributed over an interval of time in history. Such an assumption is more realistic, as it takes into consideration the memory capabilities of the drivers and the inevitable heterogeneity of their delay times. We calculate exact stability regions in the parameter space of some realistic delay distributions. Case studies are provided demonstrating the application of the results. [ABSTRACT FROM AUTHOR]