Accident; analysis and prevention
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A novel bicycle helmet concept has been developed to mitigate rotational head acceleration, which is a predominant mechanism of traumatic brain injury (TBI). This WAVECEL concept employs a collapsible cellular structure that is recessed within the helmet to provide a rotational suspension. This cellular concept differs from other bicycle helmet technologies for mitigation of rotational head acceleration, such as the commercially available Multi-Directional Impact Protection System (MIPS) technology which employs a slip liner to permit sliding between the helmet and the head during impact. This study quantified the efficacy of both, the WAVECEL cellular concept, and a MIPS helmet, in direct comparison to a traditional bicycle helmet made of rigid expanded polystyrene (EPS). ⋯ Results of this study are limited to a narrow range of impact conditions, but demonstrated the potential that rotational acceleration and the associated brain injury risk can be significantly reduced by the cellular WAVECEL concept or a MIPS slip liner. Results obtained under specific impact angles and impact velocities indicated performance differences between these mechanisms. These differences emphasize the need for continued research and development efforts toward helmet technologies that further improve protection from brain injury over a wide range a realistic impact parameters.
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Negotiations among drivers and pedestrians are common on roads, but it is still challenging for a self-driving vehicle to negotiate for its right of way with other human road users, especially pedestrians. Currently, the self-driving vehicles are programmed for conservative behavior, yielding to approaching pedestrians. Consequently, the future urban traffic will slow down significantly. ⋯ Simulation results show an overall improvement in the waiting time of vehicles and thus in the intersection throughput, compared to conservative vehicle behavior. The simulation results show also that the benefit of reduced waiting times for vehicles comes at the cost of some waiting time for pedestrians. However, the observed pedestrian waiting times in this model are not more than the generally accepted waiting times reported in empirical studies.
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In western countries, a typical car-motorcycle crash occurs at an intersection where a car manoeuvres into the path of an oncoming motorcycle, which involves a car driver violates motorcycle's right of way (ROW). In Taiwan, however, a unique type of crash (approach-turn crash) occurs when a turning (including U-turn) motorcycle frequently infringes upon a car's ROW. The primary objective of this study was to examine injuries sustained by motorcyclists in this unique type of crash. ⋯ Motorcyclists tended to be more severely or fatally injured and had increased head and face, neck, and chest and abdomen injuries when they were ROW violators than when their ROWs were violated at an intersection. Efforts to curb drunk riding and unlicensed riding may constitute effective intervention points.