The effects of closer monitoring on driver compliance with interlock restrictions

This randomized controlled trial of 2168 DWI multiple offenders assigned to a state-wide ignition interlock program in Maryland compared non-compliance with interlock requirements among drivers who were closely monitored (by Westat staff) and drivers who received standard monitoring (by the Motor Vehicle Administration). Compliance comparisons relied on datalogger data from MVA's interlock providers plus driver records that contained demographic information, prior alcohol-related traffic violations, their dispositions, and interlock duration. Measures for quantifying non-compliance included rates per 1000 engine starts for initial breath test failures at varying BAC levels and time periods, retest failures, retest refusals, interlock disconnects, startup violations, and summation measures. Regression analysis estimated the effects of closer monitoring on non-compliance, using linear mixed models that included random driver effects and fixed effects for study-group assignment, prior alcohol-related traffic violations, and months of continuous datalogger data with a quadratic function that assessed changes and rates of change in interlock non-compliance over time.All the separate non-compliance rates and summary measures derived from them were lower for closer monitored than control drivers for continuous data series of at least 6, 12, or 24 months. The differences for initial test failures and the two summary measures were statistically significant. Most measures of non-compliance decreased significantly as continuous time on the interlock increased. Parallel trends in each study group indicated that drivers learned to improve their compliance over time. Thus, this study convincingly demonstrates that closer monitoring substantially enhanced compliance with requirements of the ignition interlock and that regardless of group assignment, compliance increased over time.     

Effects of admission and treatment strategies of DWI courts on offender outcomes

Purpose

The purpose of this study is to classify DWI courts on the basis of the mix of difficult cases participating in the court (casemix severity) and the amount of involvement between the court and participant (service intensity). Using our classification typology, we assessed how casemix severity and service intensity are associated with program outcomes. We expected that holding other factors constant, greater service intensity would improve program outcomes while a relatively severe casemix would result in worse program outcomes.

Methods

The study used data from 8 DWI courts, 7 from Michigan and 1 from North Carolina. Using a 2-way classification system based on court casemix severity and program intensity, we selected participants in 1 of the courts, and alternatively 2 courts as reference groups. Reference group courts had relatively severe casemixes and high service intensity. We used propensity score matching to match participants in the other courts to participants in the reference group court programs. Program outcome measures were the probabilities of participants’: failing to complete the court's program; increasing educational attainment; participants improving employment from time of program enrollment; and re-arrest.

Results

For most outcomes, our main finding was that higher service intensity is associated with better outcomes for court participants, as anticipated, but a court's casemix severity was unrelated to study outcomes.

Conclusions

Our results imply that devoting more resources to increasing duration of treatment is productive in terms of better outcomes, irrespective of the mix of participants in the court's program.     

Parental influence on adolescent compliance with graduated driver licensing conditions and crashes as a restricted licensed driver: New Zealand Drivers Study

Aim

To examine the influence of parental knowledge of, and support for graduated driver licensing (GDL) conditions, parental management of adolescent driving and parental driving behaviour on adolescent compliance with GDL conditions and crashes as a restricted licence driver.

Method

This research was part of the New Zealand Drivers Study (NZDS), a prospective cohort study of 3992 newly licensed car drivers. NZDS participants were recruited at the learner licence stage, with follow-up aligned with the GDL stages. At the restricted licence stage 1200 parents of NZDS adolescents, aged 15–17 years at learner licensure, were recruited and completed interviews. 895 of these adolescents progressed to their full licence and completed the full licence interview. These 895 parent–adolescent pairs were the study population in this research. Topics examined included parental knowledge of, and support for GDL conditions, management of adolescent driving (driving rules, adolescent vehicle ownership, delaying licensure), and their own driving behaviours. Outcomes examined were adolescent compliance with GDL restricted licence conditions (night-time and passenger), and crashes as a driver during the restricted licence stage.

Results

After controlling for other variables, factors independently associated with adolescent low compliance with GDL conditions were: low parental knowledge of conditions, parents’ implementing few driving rules, adolescent vehicle ownership, and parent crash involvement. Factors independently associated with adolescents being a crash involved driver were: parents’ actively delaying licensure, adolescent vehicle ownership, and parent crash involvement.

Conclusion

There is increasing recognition of the importance of parental involvement in adolescent driving. The results show that parents are influential in determining adolescent compliance with GDL and risk of crash. Parents can have considerable positive influence on their adolescent's driving through ensuring compliance with the components of GDL, limiting vehicle ownership and by modelling safe driving behaviours.     

The effects of nocturnal compared with conventional hemodialysis on mineral metabolism: A randomized‐controlled trial

Hyperphosphatemia is common among patients receiving dialysis and is associated with increased mortality. Nocturnal hemodialysis (NHD) is a long, slow dialytic modality that may improve hyperphosphatemia and disorders of mineral metabolism. We performed a randomized‐controlled trial of NHD compared with conventional hemodialysis (CvHD); in this paper, we report detailed results of mineral metabolism outcomes. Prevalent patients were randomized to receive NHD 5 to 6 nights per week for 6to 10 hours per night or to continue CvHD thrice weekly for 6 months. Oral phosphate binders and vitamin D analogs were adjusted to maintain phosphate, calcium and parathyroid hormone (PTH) levels within recommended targets. Compared with CvHD patients, patients in the NHD group had a significant decrease in serum phosphate over the course of the study (0.49 mmol/L, 95% confidence interval 0.24–0.74; P=0.002) despite a significant reduction in the use of phosphate binders. Sixty‐one percent of patients in the NHD group compared with 20% in the CvHD group had a decline in intact PTH (P=0.003). Nocturnal hemodialysis lowers serum phosphate, calcium‐phosphate product and requirement for phosphate binders. The effects of NHD on PTH are variable. The impact of these changes on long‐term cardiovascular and bone‐related outcomes requires further investigation.     

The effects of driver training on simulated driving performance

Given that the beneficial effects of driver training on accident risk may not be an appropriate criterion measure, this study investigates whether professionally trained and experienced drivers exhibit safer driving behaviour in a simulated driving task compared with drivers without professional driver training. A sample of 54 police trained drivers and a sample of 56 non-police trained drivers were required to complete two tasks. Firstly to overtake a slow-moving bus on a hazardous stretch of single-lane road with bends and hills and secondly to follow a lead vehicle travelling at 55mph in a built-up section with a speed limit of 30mph. Results showed that in comparison with non-police trained drivers, police drivers were significantly less likely to cross the central division of the road at unsafe locations during the overtaking task and reduced their speed on approach to pedestrians at the roadside in the following task to a greater extent. Police drivers also adopted a more central lane position compared with non-police trained drivers on urban roads and at traffic lights during the following task. Driver group differences in simulated driving performance are discussed with reference to the implications for driver training assessment and skill development.     

The effects of vehicle model and driver behavior on risk

We study the dependence of risk on vehicle type and especially on vehicle model. Here, risk is measured by the number of driver fatalities per year per million vehicles registered. We analyze both the risk to the drivers of each vehicle model and the risk the vehicle model imposes on drivers of other vehicles with which it crashes. The "combined risk" associated with each vehicle model is simply the sum of the risk-to-drivers in all kinds of crashes and the risk-to-drivers-of-other-vehicles in two-vehicle crashes. We find that most car models are as safe to their drivers as most sport utility vehicles (SUVs); the increased risk of a rollover in a SUV roughly balances the higher risk for cars that collide with SUVs and pickup trucks. We find that SUVs and to a greater extent pickup trucks, impose much greater risks than cars on drivers of other vehicles; and these risks increase with increasing pickup size. The higher aggressivity of SUVs and pickups makes their combined risk higher than that of almost all cars. Effects of light truck design on their risk are revealed by the analysis of specific models: new unibody (or "crossover") SUVs appear, in preliminary analysis, to have much lower risks than the most popular truck-based SUVs. Much has been made in the past about the high risk of low-mass cars in certain kinds of collisions. We find there are other plausible explanations for this pattern of risk, which suggests that mass may not be fundamental to safety. While not conclusive, this is potentially important because improvement in fuel economy is a major goal for designers of new vehicles. We find that accounting for the most risky drivers, young males and the elderly, does not change our general results. Similarly, we find with California data that the high risk of rural driving and the high level of rural driving by pickups does not increase the risk-to-drivers of pickups relative to that for cars. However, other more subtle differences in drivers and the driving environment by vehicle type may affect our results.     

The impact of childhood symptoms of conduct disorder on driver aggression in adulthood

Background

Despite limited empirical investigation, existing scientific literature suggests that individuals with a history or current diagnosis of conduct disorder (CD) may be more likely to demonstrate reckless and aggressive driving. Much of the limited research in this field examines the impact of childhood CD on driver behaviour and collision risk in young adults. Few if any, studies assess the impact of this disorder on driver behaviour beyond age 21 years. The current research is a population-based study of the impact of CD symptoms during childhood on the risk of engaging in driver aggression during adulthood.

Methods

Data are based on telephone interviews with 5230 respondents who reported having driven in the past year. Data are derived from the 2011–2013 cycles of the CAMH Monitor, an ongoing cross-sectional survey of adults in Ontario, Canada aged 18 years and older. A binary logistic regression analysis of self-reported driver aggression in the previous 12 months was conducted, consisting of measures of demographic characteristics, driving exposure, problem substance use, alcohol- and drug-impaired driving, symptoms of attention deficit hyperactivity disorder, and childhood (before age 15) symptoms of CD.

Results

When entered with demographic characteristics, driving exposure, and other potential confounders, childhood symptoms of CD increased the odds of reporting driver aggression more than two-fold (adjusted OR = 2.12). Exploratory analyses of the interaction between childhood symptoms of CD and age was not a significant predictor of driver aggression.

Conclusions

Results suggest that symptoms of CD during childhood are associated with significantly increased odds of self-reported driver aggression during adulthood. Limitations and future directions of the research are discussed.     

Long‐term effects of angiotensin II blockade with irbesartan on inflammatory markers in hemodialysis patients: A randomized double blind placebo controlled trial (SAFIR study)

Introduction: Low‐grade chronic inflammation is common in hemodialysis (HD) patients. Previous studies suggest an anti‐inflammatory effect of angiotensin II receptor blocker (ARB) treatment. The aim of this study was to compare the effect of ARB vs. placebo on plasma concentrations of inflammatory markers in HD patients. Methods: Adult HD patients were randomized for double‐blind treatment with the ARB irbesartan 150–300 mg/day or placebo. At baseline, 1 week, 3, 6, 9, and 12 months plasma high sensitivity C‐reactive protein (hsCRP), interleukin (IL)?1β, IL‐6, IL‐8, IL‐18, and transforming growth factor‐β (TGF‐β) were measured using Luminex and enzyme‐linked immunosorbent assay (ELISA) technology. Findings: Eighty‐two patients were randomized (placebo/ARB: 41/41). The groups did not differ in initial levels of any of the inflammatory markers (placebo/ARB median(range)): hsCRP 3.3(0.2–23.4)/2.7(0.2–29.6) μg/mL; IL‐1β 1.1(0.0–45.9)/1.1(0.0‐7.2) pg/mL; IL‐6 10(1–90)/12(1–84) pg/mL; IL‐8 31(9–134)/34(5–192) pg/mL; IL‐18 364(188–1343)/377(213–832) pg/mL; TGF‐β 3.2(0.8–13.9)/3.6(1.3–3.8) ng/mL. Overall, there was no significant difference in hsCRP, IL‐6, IL‐8, and TGF‐β between placebo and ARB‐treated patients during the study period, and hsCRP, IL‐6, IL‐8, and TGF‐β were relatively stable during the study period (P ≥ 0.18 in all tests for parallel curves, equal levels, and constant levels). The IL‐1β level was slightly different in the two groups over time, but not significantly (P = 0.09 in test for parallel curves) and it was also relatively stable during the study period (P ≥ 0.49 in tests for equal levels and constant level). IL‐18 was the only inflammatory marker which was not constant during the study period (P = 0.001 in test for constant level), but there was no significant difference between placebo and ARB‐treated (P ≥ 0.51 in tests for parallel curves and equal levels). Discussion: Inflammatory biomarkers were neither acutely, nor in the long‐term significantly affected by the ARB irbesartan. Our findings suggest that ARB treatment in HD patients does not offer protective anti‐inflammatory effects.     

The effects of positive emotion priming on self-reported reckless driving

Five studies examined the effects of positive emotion priming on the willingness to drive recklessly. In all five, young drivers were exposed to one of the following primes of positive affect: a positive mood story; happy memories; an exciting film; a relaxing film; or thoughts on the meaning in life. Following the prime, the participants were asked to report on their willingness to drive recklessly. The responses were compared to those of groups exposed either to neutral affect, another kind of positive affect, or negative affect priming. In two of the studies, participants were also asked to report on their driving styles (risky, anxious, angry, or careful) as a second dependent variable. Positive affect, especially in the form of arousal, was found to be related to higher willingness to drive recklessly. Although men tended to report higher intentions to drive recklessly, men and women did not react differently to the emotional induction. Most interestingly, positive emotions of a relaxing nature, as well as thinking about the meaning in life, lowered the willingness to engage in risky driving. The discussion emphasizes the importance of looking for new ways to use positive emotions effectively in road safety interventions, and considers the practical implications of the studies.     

The effects of driver identity on driving safety in a retrospective feedback system

Background

Retrospective feedback that provides detailed information on a driver's performance in critical driving situations at the end of a trip enhances his/her driving behaviors and safe driving habits. Although this has been demonstrated by a previous study, retrospective feedback can be further improved and applied to non-critical driving situations, which is needed for transportation safety.

Objectives

To propose a new retrospective feedback system that uses driver identity (i.e., a driver's name) and to experimentally study its effects on measures of driving performance and safety in a driving simulator.

Method

We conducted a behavioral experimental study with 30 participants. “Feedback type” was a between-subject variable with three conditions: no feedback (control group), feedback without driver identity, and feedback with driver identity. We measured multiple aspects of participants’ driving behavior. To control for potential confounds, factors that were significantly correlated with driving behavior (e.g., age and driving experience) were all entered as covariates into a multivariate analysis of variance. To examine the effects of speeding on collision severity in driving simulation studies, we also developed a new index – momentum of potential collision – with a set of equations.

Results

Subjects who used a feedback system with driver identity had the fewest speeding violations and central-line crossings, spent the least amount of time speeding and crossing the central line, had the lowest speeding and central-line crossing magnitude, ran the fewest red lights, and had the smallest momentum of potential collision compared to the groups with feedback without driver identity and without feedback (control group).

Conclusions

The new retrospective feedback system with driver identity has the potential to enhance a person's driving safety (e.g., speeding, central-line crossing, momentum of potential collision), which is an indication of the valence of one's name in a feedback system design.     

The impact of a home visitation programme on household hazards associated with unintentional childhood injuries: A randomised controlled trial

Background

The continued high mortality and morbidity rates for unintentional childhood injuries remain a public health concern. This article reports on the influence of a home visitation programme (HVP) on household hazards associated with unintentional childhood injuries in a South African low-income setting.

Methods

A randomised controlled trial (n = 211 households) was conducted in a South African informal settlement. Community members were recruited and trained as paraprofessional visitors. Four intervention visits were conducted over 3 months, focusing on child development, and the prevention of burn, poison, and fall injuries. The HVP, a multi-component intervention, included educational inputs, provision of safety devices, and an implicit enforcement strategy. The intervention effect (IE) was measured with a standardised risk assessment index that compared post-intervention scores for intervention and control households.

Results

A significant reduction was observed in the hazards associated with electrical and paraffin appliances, as well as in hazards related to poisoning. Non-significant changes were observed for burn safety household practices and fall injury hazards.

Conclusions

This study confirmed that a multi-component HVP effectively reduced household hazards associated with electrical and paraffin appliances and poisoning among children in a low-income South African setting.     

The effects of texting on driving performance in a driving simulator: The influence of driver age

Distracted driving is a significant contributor to motor vehicle accidents and fatalities, and texting is a particularly significant form of driver distraction that continues to be on the rise. The present study examined the influence of driver age (18–59 years old) and other factors on the disruptive effects of texting on simulated driving behavior. While ‘driving’ the simulator, subjects were engaged in a series of brief text conversations with a member of the research team. The primary dependent variable was the occurrence of Lane Excursions (defined as any time the center of the vehicle moved outside the directed driving lane, e.g., into the lane for oncoming traffic or onto the shoulder of the road), measured as (1) the percent of subjects that exhibited Lane Excursions, (2) the number of Lane Excursions occurring and (3) the percent of the texting time in Lane Excursions. Multiple Regression analyses were used to assess the influence of several factors on driving performance while texting, including text task duration, texting skill level (subject-reported), texting history (#texts/week), driver gender and driver age. Lane Excursions were not observed in the absence of texting, but 66% of subjects overall exhibited Lane Excursions while texting. Multiple Regression analysis for all subjects (N = 50) revealed that text task duration was significantly correlated with the number of Lane Excursions, and texting skill level and driver age were significantly correlated with the percent of subjects exhibiting Lane Excursions. Driver gender was not significantly correlated with Lane Excursions during texting. Multiple Regression analysis of only highly skilled texters (N = 27) revealed that driver age was significantly correlated with the number of Lane Excursions, the percent of subjects exhibiting Lane Excursions and the percent of texting time in Lane Excursions. In contrast, Multiple Regression analysis of those drivers who self-identified as not highly skilled texters (N = 23) revealed that text task duration was significantly correlated with the number of Lane Excursions. The present studies confirm past reports that texting impairs driving simulator performance. Moreover, the present study demonstrates that for highly skilled texters, the effects of texting on driving are actually worse for older drivers. Given the increasing frequency of texting while driving within virtually all age groups, these data suggest that ‘no texting while driving’ education and public service messages need to be continued, and they should be expanded to target older drivers as well.     

The influence of anger,impulsivity, sensation seeking and driver attitudes on risky driving behaviour among post-graduate university students in Durban,South Africa

Introduction

Road traffic accidents (RTAs) constitute a serious global health risk, and evidence suggests that young drivers are significantly overrepresented among those injured or killed in RTAs. This study explores the role of anger, impulsivity, sensation seeking and driver attitudes as correlates for risky driving practices among drivers, drawing comparisons between age and gender.

Method

The study used a cross-sectional survey design, with a sample of 306 post-graduate university students from two universities in Durban, South Africa, who completed the self-administered questionnaire.

Results

The results indicate that drivers with higher driver anger, sensation seeking, urgency, and with a lack of premeditation and perseverance in daily activities were statistically more likely to report riskier driving acts. Males reported significantly more acts of risky driving behaviour (RDB) than females. Driver attitudes significantly predicted self-reported acts of RDB on most indicators. Older drivers (25 years and older) had safer driver attitudes and a lower sense of sensation seeking and urgency in life.

Conclusion

Interventions targeting young drivers, which focus on impeding the manifestation of anger, impulsivity and sensation seeking are recommended. Also, the empirical support for the attitude–behaviour hypothesis evidenced in this study vindicates the development or continuation of interventions that focus on this dynamic.     

The effect of chevron alignment signs on driver performance on horizontal curves with different roadway geometries

To develop a practicable and clear guideline for implementing Chevrons on China’s highways, it is necessary to understand the effect of Chevrons on driving performance in different roadway geometries.Using a driving simulator, this study tests the effect of China’s Chevrons on vehicle speed and lane position on two-lane rural highway horizontal curves with different roadway geometries.The results showed a significant effect of Chevrons on speed reduction, and this function was not significantly affected by curve radius but was statistically affected by curve direction. The speed reduction caused by Chevrons was also significant at the approach of curve, middle of curve and point of tangent. The 85th percentile speed was also markedly lower when Chevrons were present. We also found a significant effect of Chevrons in encouraging participants to drive the vehicle with a more proper lane position at the first half of curves; and this function was slightly affected by curve radius. Meanwhile, the effect of Chevrons on keeping drivers staying in a more stable lane position was also statistically significant at the second half of curves. In sharp curves, the function of Chevrons to make drivers keep a stable lane position was lost. Besides, the impact of curve direction on the function of Chevrons on lane position was always present, and drivers would drive slightly away from Chevrons.Regardless of the curve radius, China’s Chevrons at horizontal curves provide an advance warning, speed control and lane position guide for traffic on the nearside of Chevrons. Besides, combing with the function of Chevrons on preventing excessive speed and the benefit to make drivers keep a more proper lane position, China’s Chevrons appear to be of great benefit to reduce crashes (e.g., run-off-road) in curves.     

The effects of driving experience on responses to a static hazard perception test

Novice drivers exhibit deficits in hazard perception that are likely to increase their risk of collisions. We developed a static hazard perception test that presents still images to observers and requires them to indicate the presence of a traffic conflict that would lead to a collision. Responses to these scenes were obtained for young adult novice (N = 29) and experienced drivers (N = 27). Additionally, participants rated the hazard risk and clutter of each scene. Novice drivers rated traffic conflicts as less hazardous and responded more slowly to them. Using a subset of 21 scenes, we were able to discriminate novice and experienced young adult drivers with a classification accuracy of 78% and a scale reliability (Cronbach's alpha) of .91. The potential applications of this research include the development of standardized hazard perception tests that can be used for driver evaluation, training and licensure.     

The impact of driver education on self-reported collisions among young drivers with a graduated license

In this study, we assess the impact of driver education on the risk of collisions in a Graduated Licensing System (GLS). Ontario's GLS requires all new drivers to successfully pass through two stages of graduated license (referred to as G1 and G2, respectively) before full licensure is granted. Surveys of driving behaviour and related factors were administered to Grades 11 and 12 students with a graduated license in seven Ontario schools in 1996 and 1998. A total of 1533 students completed the survey in 2 years. Multivariate logistic regression analysis revealed a significantly lower odds of self-reported collision involvement among G1 license holders with driver education (OR: 0.31, 95% CI: 0.12-0.83). No significant effects were observed for G2 license holders. Other significant predictors of collisions include sex of driver, months of licensure and kilometers driven for G2 license holders. These results suggest that the impact of driver education may be dependent on the stage of driver learning in which it occurs.     

The effects of a new traffic safety law in the Republic of Serbia on driving under the influence of alcohol

The aim of the study presented here has been to see what the effects of the new traffic safety law are, 2 years into its initial implementation, on driving under the influence of alcohol. Until the end of 2009, the legal limit for blood concentration for drivers in Serbia was 0.5 g/l; however, the new traffic safety law stipulates the new limit to be 0.3 g/l. A retrospective autopsy study was performed over a 6-year period (from 2006 to 2011) whose sample covered cases of fatally injured drivers who had died at the scene of the incident, before being admitted to hospital. A total of 161 fatally injured drivers were examined for their blood alcohol concentration. The average age for these drivers was 40.2 ± 15.4 years, with a significant male predominance of 152 men to 9 women (χ² = 152.000, p < 0.001). This study has shown no decrease in the ratio of drivers under the influence of alcohol vs. all drivers (Pearson χ² = 4.415, df = 5, p = 0.491), nor in the number of drivers under the influence of alcohol (Pearson χ² = 6.629, df = 5, p = 0.250), nor a decrease in the mean blood alcohol concentration in drivers (1.72 ± 0.87 vs. 1.68 ± 0.95 g/l, t = 0.177, df = 80, p = 0.860). The conclusion of this study is that the new law has had a limited effect on driving under the influence of alcohol, which still remains one of the major human factors, responsible for road-traffic crashes in Serbia.     

The relationship of dangerous driving with traffic offenses: A study on an adapted measure of dangerous driving

Using data from three different samples and more than 1000 participants, the current study examines differences in dangerous driving in terms of age, gender, professional driving, as well as the relationship of dangerous driving with behavioral indicators (mileage) and criteria (traffic offenses). The study uses an adapted (Romanian) version of the Dula Dangerous Driving Index (DDDI, Dula and Ballard, 2003) and also reports data on the psychometric characteristics of this measure. Findings suggest that the Romanian version of the DDDI has sound psychometric properties. Dangerous driving is higher in males and occasional drivers, is not correlated with mileage and is significantly related with speeding as a traffic offense, both self-reported and objectively measured. The utility of predictive models including dangerous driving is not very large: logistic regression models have a significant fit to the data, but their misclassification rate (especially in terms of sensitivity) is unacceptable high.     

青藏高原“敏感区”对我国灾害天气气候的影响及其监测

根据中国区域大范围洪涝、暴雨、暴雪天气预报上游关键区,以及气候变化敏感区多圈层信息平台等重大需求.从"世界屋脊"青藏高原为灾害性天气上游关键区与气候信号敏感区的观点出发,提出高原及周边观测工程建网新思路与应用新技术方案,设计、构建了新一代气象综合观测预警长期监测系统,实现科学试验-工程建设-工程应用开发途径,发展高原及周边敏感区灾害天气上游早期预警系统监测平台,为灾害性天气预报与区域气候变化提供多功能业务服务应用平台;采用高原东缘南-北轴向观测数据信息(GPS监测站与AWS站)应用于改进WRF(weather research and forecasts)模式三维变分方案,实现了模式优化站网信息的同化技术,可提升中国区域暴雨、南方雪灾模式预报能力.针对夏季暴雨、南方暴雪,检验、证明了高原观测工程布网"早期预警"的显著效果.     

The impact of distractions on young adult drivers with attention deficit hyperactivity disorder (ADHD)

Young adults with attention deficit hyperactivity disorder (ADHD) are at higher risk for being involved in automobile crashes. Although driving simulators have been used to identify and understand underlying behaviors, prior research has focused largely on single-task, non-distracted driving. However, in-vehicle infotainment and communications systems often vie for a driver's attention, potentially increasing the risk of collision. This paper explores the impact of secondary tasks on individuals with and without ADHD, a medical condition known to affect the regulation of attention. Data are drawn from a validated driving simulation representing periods before, during, and after participation in a secondary cognitive task. A hands-free phone task was employed in a high stimulus, urban setting and a working memory task during low stimulus, highway driving. Drivers with ADHD had more difficulty on the telephone task, yet did not show an increased decrement in driving performance greater than control participants. In contrast, participants with ADHD showed a larger decline in driving performance than controls during a secondary task in a low demand setting. The results suggest that the interaction of the nature of the driving context and the secondary task has a significant influence on how drivers with ADHD allocate attention and, in-turn, on the relative impact on driving performance. Drivers with ADHD appear particularly susceptible to distraction during periods of low stimulus driving.