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41.
    
Abstract

Studies have used the latent differential equation (LDE) model to estimate the parameters of damped oscillation in various phenomena, but it has been shown that correct, non-zero parameter estimates are only obtained when the latent series exhibits little or no process noise. Consequently, LDEs are limited to modeling deterministic processes with measurement error rather than those with random behavior in the true latent state. The reasons for these limitations are considered, and a piecewise deterministic approximation (PDA) algorithm is proposed to treat process noise outliers as functional discontinuities and obtain correct estimates of the damping parameter. Comprehensive, random-effects simulations were used to compare results with those obtained using a state-space model (SSM) based on the Kalman filter. The LDE with the PDA algorithm (LDEPDA) successfully recovered the simulated damping parameter under a variety of conditions when process noise was present in the latent state. The LDEPDA had greater precision and accuracy than the SSM when estimating parameters from data with sparse jump discontinuities, but worse performance for diffusion processes overall. All three methods were applied to a sample of postural sway data. The basic LDE estimated zero damping, while the LDEPDA and SSM estimated moderate to high damping. The SSM estimated the smallest standard errors for both frequency and damping parameter estimates.  相似文献   
42.
    
This research examined different conceptualisations and measurements of adaptability in a university context. We compared two approaches to adaptability: (1) personal attribute and (2) performance construct. In the extant literature, the former is dominated by self-report measures, whereas the latter is dominated by performance-based tasks. In two studies, we developed and tested the factorial structure of self-report adaptability measures and the factorial structure of performance-based tasks. Self-report measures of adaptability converged into two factors: adaptability and inflexibility. Performance-based metrics of adaptability did not converge, however. Self-reported and performance measures were unrelated, calling for a multitrait-multimethod approach to further evaluate construct validity of adaptability measurement. Self-reported adaptability was related to Big-5 personality, whilst performance-based adaptability was related to cognitive abilities.  相似文献   
43.
44.
    
Behavior analysis procedures have been used to improve sports performance and enhance player safety across a wide variety of sports. The current study evaluated the effects of behavioral skills training on three common field hockey shots, a slap shot, drive, and sweep for young field hockey players. The procedures were evaluated in a multiple baseline across behaviors for three players. Results showed increases in each type of shot once intervention was implemented.  相似文献   
45.
The present study aims at testing the effects of cultural intelligence (metacognitive, cognitive, motivational and behavioural facets) onto job performance in expatriation (dimensions relevant to task, effort demonstration, leadership, discipline maintenance, communication, administrative and managerial responsibilities) mediated by cross-cultural adjustment (global, interactional and job facets). Data are collected via an electronic survey administered to French expatriates (N = 201) and further processed in SPSS 20.0 and Lisrel 8.80. An output latent variable model globally confirms a mediation hypothesis and leads to a number of original findings. Namely, motivational and behavioural facets of cultural intelligence have the largest effect onto job performance in expatriation, while metacognitive facet has no effect at all. As regards job performance itself, the task dimension is the least dependent upon cultural intelligence and cross-cultural adjustment as compared to job performance aspects relevant to workplace relationships and team management (e.g., communication or leadership performance). The results are discussed in terms of their novelty and several research perspectives are proposed.  相似文献   
46.
    
Emotion is an important factor that influences driving behavior, but the mechanism is unclear. This research explored the effect of the emotional state on simulated driving behavior. Thirty-five licensed drivers participated in this study and completed a car-following task. The angry, happy and neutral states were manipulated during the task. The participants’ driving performance and risk perception were recorded under each emotional state. Trait anger and driving experience were also measured to explore the possible mediating effect. The results showed that the drivers in an angry or happy emotional state tended to maintain less time to collision and take a longer time to brake while following a lead vehicle than the drivers under the neutral condition, suggesting that drivers in emotional states are more dangerous those in neutral states. Moreover, the happy state rendered the drivers more dangerous, which manifested as a lower perceived accident risk than that among the drivers in the angry and neutral states. More specifically, experienced drivers in happy states performed worse with respect to vehicle lateral position control. Recommendations and implications for safety education and further research are discussed.  相似文献   
47.
    
Attitudes of a sample of 211 UK people who are blind concerning autonomous vehicles (AVs), and the determinants of the willingness of people who are blind to travel in AVs, were examined. Participants answered an open-ended question regarding their attitudes towards level 5 AVs and the results were analysed using a semi-automated structural topic modelling procedure. (Level 5 AVs are fully autonomous anywhere, and do not require controlled areas in which to operate.) Four “topics” emerged from the exercise: (i) “hope” for future independence and freedom to travel offered by AVs to people who are blind, (ii) scepticism that AVs will ever be configured to meet the needs of people who are blind, (iii) concerns over safety, and (iv) the affordability of AVs. The four topics were employed as mediating variables in a structural equation model designed to explain the respondents’ willingness to travel in an AV. A number of covariates were presumed to influence the four mediating topics, including a participant’s desire for independence, comorbidity, locus of control, and level of generalised anxiety. Three of the mediating variables exerted significant influences on willingness to travel in an AV, i.e., hope for future independence, misgivings about safety, and affordability. Scepticism about AVs did not have a significant effect. Several implications for AV design and for the creation of public information messages promoting AVs are suggested. In particular, public information campaigns should emphasise the freedom to travel that AVs will provide for people who are blind; reassurances concerning safety; and the inevitability of AVs appearing on the roads of economically developed countries.  相似文献   
48.
    
A driver’s license is key to independence for many young adults, including those with autism spectrum disorders (ASDs). However, individuals with ASDs may face special challenges when learning to drive. If effective driver training is to be devised for this demographic, it is important to determine the nature of these challenges. Driving inherently requires multitasking (e.g. steering, speed maintenance, navigation, hazard detection) and drivers are routinely obligated to combine driving with the demands of listening and responding to others, as occurs during driving lessons. Given that individuals who display traits associated with ASDs may have special difficulties with secondary tasks and especially those that involve socialization, we examined the effects of secondary tasks that involve listening and responding to questions while driving. We compared performance when simply driving (the control condition), driving while listening (the audiobook condition), and driving while listening and speaking (the prompt: answer condition). The autism spectrum quotient (AQ:Baron-Cohen, Wheelwright, Skinner, Martin, & Clubley, 2001), a commonly used self-report questionnaire intended to measure traits associated with ASDs in research, was used to identify young drivers with more and fewer traits related to ASDs in a community sample, (None had a clinical diagnosis of ASD.) Consistent with studies of drivers clinically diagnosed with ASDs, we found that high AQ scorers reported greater mental and physical demand, effort, and frustration when driving, and showed more moment-to-moment variability in lane position and hazard reaction compared to low AQ scorers as measured in a driving simulator. Differences between the low and high scorers were typically largest when secondary tasks were imposed, but the predicted interaction between drive condition and AQ group only emerged in terms of steering variability.  相似文献   
49.
It is largely accepted that drink-driving significantly increases the likelihood that a driver may engage in risk-taking behavior and thus road crash. Although there have been a few studies examining the effect of blood alcohol concentration (BAC) on rider performance in developed countries, there has not been any research on the effect of BAC levels on motorcycle rider’s performance in developing countries. This study is attempted to evaluate the effect of low BAC levels (i.e., ≤0.05 g/dL or 0.05) on riding performance of motorcycle riders in Vietnam using an advanced motorcycle riding simulator. Thirty-four motorcycle riders aged 18–40 complete simulated rides on three BAC levels, namely 0.00, 0.02, and 0.05. Riding performance indicators are measured and compared at different BAC levels. These indicators include average speed, average lateral overtaking distance, brake reaction time, acceleration, deceleration, and frequency of lane change. At the level BAC = 0.02 or lower, the negative effects on the rider’s ability to control a motorcycle safely are statically insignificant. At the level BAC = 0.05, all the performances are impaired and the negative effects become statistically significant. In comparison of between novice participants and experienced participants at the same level of BAC, mean speed and acceleration rates of novice participants are significantly higher than the experienced participant. Based on the findings, the paper further discusses empirical relationships between reduced riding performances and road crash risk, and insights into drink-riding deterrence policy-making with regard to motorcycle riders.  相似文献   
50.
    
Older drivers are at a severely higher risk for motor vehicle crash involvement. Due to the global aging of the population, this increased crash risk has a significant impact on society, as well as on an older individual’s quality of life. For this reason, there is a need for understanding how normal age-related changes in cognition and underlying brain dynamics impact driving performance to identify the functional and neurophysiological biomarkers that could be used to design strategies to preserve or improve safe driving behavior in older persons. This review provides an overview of the literature on age-related changes in cognitive functioning and brain dynamics that impact driving simulator performance of healthy persons. A systematic literature search spanning the last ten years was conducted, resulting in 22 eligible studies. Results indicated that various aspects of cognition, most importantly executive function, complex attention, and dual tasking, were associated with driving performance, irrespective of age. However, there was a distinct age-related decline in cognitive and driving performance. Older persons had a more variable, less consistent driving simulator performance, such as more variable speed adaptation or less consistent lane keeping behavior. Only a limited number of studies evaluated the underlying brain dynamics in driving performance. Therefore, future studies should focus on implementing neuroimaging techniques to further unravel the neural correlates of driving performance.  相似文献   
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