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91.
《Ergonomics》2012,55(9):640-648
Around 40% of 10–11-year-old children receive cycle training every year in the UK, but concern has been expressed over the efficacy of training courses. One argument is that accidents occur too infrequently to be a viable evaluative criterion, and attitudes and behaviour have been suggested as alternatives. A questionnaire that measured a number of variables including accidents, attitudes, and behaviour was completed by 336 participants from two schools in the London Borough of Bromley. At least one cycling injury had been sustained by 58.3% of respondents, requiring hospital treatment in 19.1% of cases. Girls reported fewer accidents than boys. No relationship between training and accidents was found. A principal components analysis (PCA) of the attitudes items produced a ‘safe attitudes’ factor. Girls displayed ‘safer’ attitudes, but there was no evidence that training produced safer attitudes. A PCA of the cycling behaviour scales produced two factors, ‘safe cycling’ and ‘showing off’. Safe cyclists who obeyed basic safety rules were less likely to sustain cycle injuries, but showing off was not related to accidents. Girls were less likely to show off, but the safe behaviour gender difference did not reach significance. Training did not relate to either factor. 相似文献
92.
Rollover crash is one of the major types of traffic crashes that induce fatal injuries. It is important to investigate the factors that affect rollover crashes and their influence on driver injury severity outcomes. This study employs support vector machine (SVM) models to investigate driver injury severity patterns in rollover crashes based on two-year crash data gathered in New Mexico. The impacts of various explanatory variables are examined in terms of crash and environmental information, vehicle features, and driver demographics and behavior characteristics. A classification and regression tree (CART) model is utilized to identify significant variables and SVM models with polynomial and Gaussian radius basis function (RBF) kernels are used for model performance evaluation. It is shown that the SVM models produce reasonable prediction performance and the polynomial kernel outperforms the Gaussian RBF kernel. Variable impact analysis reveals that factors including comfortable driving environment conditions, driver alcohol or drug involvement, seatbelt use, number of travel lanes, driver demographic features, maximum vehicle damages in crashes, crash time, and crash location are significantly associated with driver incapacitating injuries and fatalities. These findings provide insights for better understanding rollover crash causes and the impacts of various explanatory factors on driver injury severity patterns. 相似文献
93.
94.
Regardless of the different theoretical positions held at present, we can probably agree that an abusive and problematic use of the Internet exists. We present an instrumental study whose objective is to develop a brief, valid, and reliable questionnaire to measure this abuse in epidemiological contexts. The Internet Abusive Use Questionnaire (IAUQ) consists of 12 items to respond to according to the Likert scale. A total of 908 respondents participated, 48% males, with ages ranging between 17 and 70 years. The IAUQ showed a single factor structure. This model presents a good adjustment, with CFI, GFI, and NFI fit index over .90. Internal consistency was found to be .90. The IAUQ showed direct correlations with the Internet abusive use self-assessment, anxiety and depression, and inverse correlations with quality of life. All correlations were significant (p < .001), which demonstrated convergent validity. Significant differences were also found in the IAUQ scores among groups with different age, cultural level, and other addictions, which evidenced discriminant validity. In conclusion, the obtained results demonstrate structural validity and adequate indices of convergent validity and discriminative capacity. These psychometric characteristics —combined with the fact that the IAUQ evaluates harmful use of Internet briefly and simply— fulfill our goal. 相似文献
95.
IntroductionThe current study builds on previous versions of the Driver Behaviour Questionnaire (DBQ) by incorporating a larger sample of driving behaviors targeting inattention, distraction, aggressive driving, and health related to aging. The goals of this study were to determine if the resulting factor structure was consistent with a more contemporary view of unsafe driving behaviors, and to determine whether scores on the factors could predict self-reported collisions and police citations.MethodsThe instrument was given to a sample of 3295 drivers ranging in age from 19 to 80+ years old. It was divided in two sections, the first to provide demographic information and driving history data and the second containing 105 driver behavior questions.ResultsAn exploratory factor analysis resulted in a 65-item scale organized in four factors. The factors were labeled tentatively as Inattention Errors, Age-Related Problems, Distraction and Hurry, and Aggressive Violations. Regression analyses showed that the factors were predictors of self-reported, at-fault collisions and police citations.Practical implicationsThe factor scores found in this research are consistent with a useful theoretical framework for understanding unsafe driver actions, and demonstrate some potential to identify several individual difference variables that predict self-reported collisions and citations. 相似文献
96.
《Ergonomics》2012,55(9):605-618
When most of the driving tasks are performed automatically, a driver's level of alertness may decline, as has been pointed out in the study of the phenomenon called ‘highway hypnosis’. One possible countermeasure is to periodically vary the speed (Wertheim 1978), but the authors have not found any studies that directly assess the effectiveness of this countermeasure. The objective of our study has been to provide empirical evidence regarding the effects of this strategy on the level of driver activation on a motorway route in real traffic. In the present study activation level as indexed by a relative measure based on slow EEG activity tended to be significantly higher when speed was modified periodically than when it remained constant. In addition, this index tended to be progressively higher when the speed was constant during the first part of the route, while the same thing did not occur when the speed was modified periodically. Finally, no significant differences between the constant and varying speed conditions were obtained with respect to any of the cardiovascular indices related to the effort put into driving and the stress experienced in the situation. 相似文献
97.
《Ergonomics》2012,55(4):507-513
In a study of load carriage on the head on the level, high degrees of correlation worn obtained with the gross weights transported (viz. body weight and given load) and the energy expenditures, r = 0-91. Their relationship fits the equation, E(kcal/ minute) = 0.0943 (body weight+load carried) —2.183. The gross weight transported was also found to have an equally high correlation with the peak heart rates observed (r = 0.88) and the regression equation, PHR= 1.2552 (body weight-f load carried+-24.87, mathematically describes the relationship of the two latter variables. These equations can conveniently be utilized for field studies of load carrying in many underdeveloped countries where the common mode of load carriage is identical with that investigated hero and the average body weight of the subjects similar to that of the manual workers in this country, viz., around.50 kg 相似文献
98.
This research proposes that it is possible to deliberately reduce temporal tensions in order to promote energy saving behaviours. People may not dedicate enough time to planning their tasks that consume energy, rushing into them without much deliberation. They may also use more energy than necessary in an attempt to accelerate processes that seem to be taking too long, to reduce the boredom of waiting. Persuasive technology provided the tools to manipulate the perception of time and therefore elicit changes in the specific behaviours that result in unnecessary energy usage. Cooking tasks were used as the scenario to test behaviour change strategies delivered via a smartphone application. Results showed that these strategies facilitated the performance of sustainable behaviours. Participants reported that the app made (1) them more likely to follow the steps needed to use less energy, (2) the activity more enjoyable and (3) the time appear to pass more quickly compared to a control version. 相似文献
99.
This analysis has been conducted to explore the validity and reliability of the Food Choice Questionnaire (FCQ) across 9 European countries. Variation in the factor structure and the perceived importance of food choice motives have been compared cross-nationally. Volunteers (N = 9381) were recruited from an existing panel of a social research agency to take part in the Food4Me survey in Germany, Greece, Ireland, Poland, Portugal, Spain, the Netherlands, the UK and Norway. The survey was administered on-line. Configural, metric and scalar invariance fell within acceptable limits and were consistent across the 9 countries. All reliability parameters were above acceptable levels. Factor analysis confirmed that all items loaded onto the same 9 factors established by Steptoe and Pollard (1995). There was highly significant agreement in the relative importance of food choice factors between countries. Price was ranked as most important food choice factor in five countries (Spain, Greece, Ireland, Portugal and the Netherlands), sensory appeal was ranked first for three countries (Norway, Germany and the UK) while natural content was ranked as the most important factor in Poland. Familiarity and ethical concern were consistently ranked as least important in all countries. These data suggest that the FCQ is a suitable tool for exploring food choice motives across different European populations. Differences in relative importance of factors within countries may need to be taken into account in dietary health intervention and food product development. 相似文献
100.
《Ergonomics》2012,55(8):964-982
Advances in motor vehicle engineering will allow greater refinement of the dynamic qualities of passenger cars in the near future. This paper describes the development and initial validation of a reliable and valid multidimensional scale to assess these parameters based upon a technique previously developed to evaluate aircraft handling qualities. The scaling methodology developed emphasizes the interaction between the vehicle's dynamic behaviour and the category of vehicle (e.g. sports car, executive saloon). This three-part study describes the initial extraction and the subsequent verification of the scale dimensions from an analysis of the opinions of circa 500 drivers, followed by an evaluation of the sensitivity and diagnosticity of the scale to distinguish between the road behaviour exhibited by vehicle types. The results suggest that the scale shows both content and construct validity, being able to distinguish both between broad categories of vehicle and different models of vehicle within a particular category in a consistent and meaningful manner. 相似文献