PurposeThis field study was designed to compare to what degree various proportions of studded and unstudded winter tyres affect the roughness and polishing of road surfaces covered with ice and compact snow.MethodsTest cars equipped with studded and unstudded winter tyres drove around a test track according to the designed procedure. The main straight section of the track had five lanes, each with a different proportion of cars with studded tyres: 100%, 75%, 50%, 25% and 0% of the respective lane traffic. The remainder were cars with unstudded winter tyres. Each lane included sections of ice and compact snow with subsections for constant speed, braking and acceleration. The lanes were driven 642 times. The ambient temperature was approximately 0 °C during the test.ResultsThe overall results showed that there was no substantial difference in friction of the road surface between lanes having 100%, 75% or 50% of cars with studded tyres. However, the friction was much poorer in lanes having fewer cars with studded tyres.ConclusionsThese results suggest that traffic with 50% of cars having studded tyres results in adequate friction of icy road surfaces in the test conditions.
引用量:0发表时间:2016年
PurposeDepending on the calibration of their cognitive abilities, some older drivers (ODs) might stop driving prematurely (under-estimators, UEs) and others could expose themselves to risky situations (over-estimators, OEs). The aim of the study was to compare the effectiveness of two cognitive training (CT) programs intended for ODs presenting a cognitive calibration bias. We hypothesized that CT with feedback on performance can help ODs to correctly calibrate their abilities and consequently adapt their driving behavior.MethodOne hundred and six ODs (≥70 years) were assigned to two CT groups (with or without a driving simulator experience, DS). These interventions lasted about 36 h and were distributed over a 3-month period. ODs completed objective and subjective cognitive evaluations and an on-road driving evaluation before and after training.ResultsThe first results on 67 participants (40 from the CT group, and 27 from the CT + DS group) showed an improvement of their visual processing speed, their divided attention and their selective attention after training. Participants from both groups also had an improved TRIP tactical sub-score (Test Ride for Investigating Practical fitness to drive), indicating a better driving behavioral adaptation. Finally, although both training programs seemed to be equally effective in correcting cognitive calibration bias, the results indicated that 21 UEs and 10 OEs were well calibrated and thus correctly self-assessed their cognitive abilities after training.ConclusionBoth CT programs (with or without DS experience) seem to improve the visual attention of ODs. UEs appeared to be more susceptible than OEs to this training and were better calibrated after it.
国际铁路运输杂志
INTERNATIONAL JOURNAL OF RAIL TRANSPORTATION
欧洲交通研究综述
EUROPEAN TRANSPORT RESEARCH REVIEW
计算机辅助土木和基础设施工程
COMPUTER-AIDED CIVIL AND INFRASTRUCTURE ENGINEERING