Psychophysiological Measures of Driver Distraction and Workload While Intoxicated

The crash risk associated with cell phone use while driving is acontentious issue. Many states are introducing Advanced Traveler InformationSystems (ATIS) that may be accessed with cell phones while driving (e.g., 511Traveler Information Services). In these contexts, there is a need for relevantresearch to determine the risk of cell phone use. This study compared driverperformance while conversing on a hands-free cell phone to conditions ofoperating common in-vehicle controls (e.g., radio, fan, air conditioning) andalcohol intoxication (BAC 0.08). In addition, the study examined the combinedeffects of being distracted and being intoxicated given that there may be a higherrisk of a crash if the driver engages in a combination of risk factors. Duringsimulated traffic scenarios, resource allocation was assessed through an eventrelatedpotential (ERP) novelty oddball paradigm. Intoxicated drivers were lessattentive to all stimuli and drivers engaged in secondary tasks had weakerresponses to unexpected novel sounds in brain regions associated with evaluativeprocessing. Drivers conversing on the cell phone and in-vehicle tasks while soberhad lower accuracy during the target tone task than intoxicated drivers notcompleting any secondary task

A new approach to railway track switch actuation:dynamic simulation and control of a self-adjusting switch

The track switch is one of the key assets in any railway network. It is essential to allow trains to change route; however, when it fails significant delays are almost inevitable. A relatively common fault is ‘loss of detection’, which can happen when gradual track movement occurs and the switch machines (actuators) no longer close the gap between the switch rail and stock rail to within safe tolerances. Currently, such misalignment is mitigated by a preventative programme of inspection and manual re-adjustment. In contrast to many other industries, the actuators are exclusively operated in open-loop with sensors (often limit switches) mainly being used for detection. Hence, an opportunity exists to investigate closed-loop control concepts for improving the operation of the switch. This paper proposes two advances; first, a novel approach is taken to modelling the dynamic performance of track switch actuators and the moving permanent-way components of the switch. The model is validated against real data from an operational switch. Secondly, the resulting dynamic model is then used to examine the implementation of closed-loop feedback control as an integral part of track-switch actuation. The proposed controller is found to provide suitable performance and to offer the potential of ‘self-adjustment’ i.e., re-adjust itself to close any gap (within a predefined range) between the stock and switch rails; thereby completing the switching operation