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181.
Background: Alcohol use is pervasive among motorists on the road in Ghana; however, we do not know the extent to which this behavior is implicated in road accidents in this country.

Objectives: The main objective of this research was to establish the prevalence of alcohol in the blood of nonfatally injured casualties in the emergency departments (EDs) in northern Ghana.

Method: Participants were injured road traffic crash victims, namely, pedestrians, cyclists, motorcyclists, and drivers seeking treatment at an ED. The study sites were 2 level III trauma centers located in Wa and Bolgatanga. Participants were screened for alcohol followed by breath tests for positive participants using breathalyzers.

Results: Two hundred and sixty-two accident victims visited EDs, 58% of whom were in Wa. Among the victims, 41% were hospitalized and 57% experienced slight injuries. The vast majority (76%) of the casualties were motorcyclists, 13% were pedestrians, 8% were cyclists, and 2% were drivers. Casualties who had detectable alcohol in their blood were predominantly vulnerable road users. In all, 34% of participants had detectable blood alcohol concentrations (BACs) and the mean BAC for all casualties who tested positive and could give definitive BACs was 0.2265 (226 mg/dl). The prevalence of alcohol use was 53% among cyclists, 34% among motorcyclists, 21% among pedestrians, and 17% among drivers. Male casualties were more likely to test positive for alcohol than females. In addition, the prevalence of alcohol was significantly higher among injured casualties in Bolgatanga compared to Wa.

Conclusion: There was a high prevalence of alcohol use among nonfatally injured casualties in northern Ghana and injury severity increased with BAC. AUDIT screening in the hospital, alcohol consumption guideline, road safety education with an emphasis on minimizing or eliminating alcohol consumption, and enhanced enforcement of the BAC limit among motorists are recommended.  相似文献   

182.
Objective: Our study measured the change in head injuries and deaths among motorcycle users in Cu Chi district, a suburban district of Ho Chi Minh City.

Methods: Hospital records for road traffic injuries (RTIs) were collected from the Cu Chi Trauma Centre and motorcycle-related death records were obtained from mortality registries in commune health offices. Head injury severity was categorized using the Abbreviated Injury Score (AIS). Rate ratios (RRs) were used to compare rates pre- and post-law (2005/2006–2009/2010). Cu Chi's population, stratified by year, age, and sex, was used as the denominator.

Results: Of records identifying the transportation mode at the time of injury, motorcyclists accounted for most injuries (3,035, 87%) and deaths (238, 90%). Head injuries accounted for 70% of motorcycle-related hospitalizations. Helmet use was not recorded in any death records and not in 97% of medical records. Males accounted for most injuries (73%) and deaths (88%). The median age was 28 years and 32 years for injuries and deaths, respectively. Compared to the pre-law period, rates of motorcycle injuries (RR = 0.53; 95% confidence interval [CI], 0.49–0.58), head injuries (RR = 0.35; 95% CI, 0.31–0.39), severe head injuries (RR = 0.47; 95% CI, 0.34–0.63), and deaths (RR = 0.69; 95% CI, 0.53–0.89) significantly decreased in the post-law period.

Conclusions: Rates of head injuries and deaths among motorcycle riders decreased significantly after implementation of the mandatory helmet law in Vietnam. To further examine the impact of the motorcycle helmet law, including compliance and helmet quality, further emphasis should be placed on gathering helmet use data from injured motorcyclists.  相似文献   

183.
Objective: The present research relies on 2 main objectives. The first is to investigate whether latent model analysis through a structural equation model can be implemented on driving simulator data in order to define an unobserved driving performance variable. Subsequently, the second objective is to investigate and quantify the effect of several risk factors including distraction sources, driver characteristics, and road and traffic environment on the overall driving performance and not in independent driving performance measures.

Methods: For the scope of the present research, 95 participants from all age groups were asked to drive under different types of distraction (conversation with passenger, cell phone use) in urban and rural road environments with low and high traffic volume in a driving simulator experiment. Then, in the framework of the statistical analysis, a correlation table is presented investigating any of a broad class of statistical relationships between driving simulator measures and a structural equation model is developed in which overall driving performance is estimated as a latent variable based on several individual driving simulator measures.

Results: Results confirm the suitability of the structural equation model and indicate that the selection of the specific performance measures that define overall performance should be guided by a rule of representativeness between the selected variables. Moreover, results indicate that conversation with the passenger was not found to have a statistically significant effect, indicating that drivers do not change their performance while conversing with a passenger compared to undistracted driving. On the other hand, results support the hypothesis that cell phone use has a negative effect on driving performance. Furthermore, regarding driver characteristics, age, gender, and experience all have a significant effect on driving performance, indicating that driver-related characteristics play the most crucial role in overall driving performance.

Conclusions: The findings of this study allow a new approach to the investigation of driving behavior in driving simulator experiments and in general. By the successful implementation of the structural equation model, driving behavior can be assessed in terms of overall performance and not through individual performance measures, which allows an important scientific step forward from piecemeal analyses to a sound combined analysis of the interrelationship between several risk factors and overall driving performance.  相似文献   

184.
Objective: This study investigated drivers' evaluation of a conventional autonomous emergency braking (AEB) system on high and reduced tire–road friction and compared these results to those of an AEB system adaptive to the reduced tire–road friction by earlier braking. Current automated systems such as the AEB do not adapt the vehicle control strategy to the road friction; for example, on snowy roads. Because winter precipitation is associated with a 19% increase in traffic crashes and a 13% increase in injuries compared to dry conditions, the potential of conventional AEB to prevent collisions could be significantly improved by including friction in the control algorithm. Whereas adaption is not legally required for a conventional AEB system, higher automated functions will have to adapt to the current tire–road friction because human drivers will not be required to monitor the driving environment at all times. For automated driving functions to be used, high levels of perceived safety and trust of occupants have to be reached with new systems. The application case of an AEB is used to investigate drivers' evaluation depending on the road condition in order to gain knowledge for the design of future driving functions.

Methods: In a driving simulator, the conventional, nonadaptive AEB was evaluated on dry roads with high friction (μ = 1) and on snowy roads with reduced friction (μ = 0.3). In addition, an AEB system adapted to road friction was designed for this study and compared with the conventional AEB on snowy roads with reduced friction. Ninety-six drivers (48 males, 48 females) assigned to 5 age groups (20–29, 30–39, 40–49, 50–59, and 60–75 years) drove with AEB in the simulator. The drivers observed and evaluated the AEB's braking actions in response to an imminent rear-end collision at an intersection.

Results: The results show that drivers' safety and trust in the conventional AEB were significantly lower on snowy roads, and the nonadaptive autonomous braking strategy was considered less appropriate on snowy roads compared to dry roads. As expected, the adaptive AEB braking strategy was considered more appropriate for snowy roads than the nonadaptive strategy. In conditions of reduced friction, drivers' subjective safety and trust were significantly improved when driving with the adaptive AEB compared to the conventional AEB. Women felt less safe than men when AEB was braking. Differences between age groups were not of statistical significance.

Conclusions: Drivers notice the adaptation of the autonomous braking strategy on snowy roads with reduced friction. On snowy roads, they feel safer and trust the adaptive system more than the nonadaptive automation.  相似文献   

185.
Abstract

Objective: The current study investigated whether older drivers’ driving patterns during a customized on-road driving task were representative of their real-world driving patterns.

Methods: Two hundred and eight participants (male: 68.80%; mean age?=?81.52 years, SD?=?3.37 years, range?=?76.00–96.00 years) completed a customized on-road driving task that commenced from their home and was conducted in their own vehicle. Participants’ real-world driving patterns for the preceding 4-month period were also collected via an in-car recording device (ICRD) that was installed in each participant’s vehicle.

Results: During the 4-month period prior to completing the on-road driving task, participants’ median real-world driving trip distance was 2.66?km (interquartile range [IQR]?=?1.14–5.79?km) and their median on-road driving task trip distance was 4.41?km (IQR?=?2.83–6.35?km). Most participants’ on-road driving task trip distances were classified as representative of their real-world driving trip distances (95.2%, n?=?198).

Conclusions: These findings suggest that most older drivers were able to devise a driving route that was representative of their real-world driving trip distance. Future research will examine whether additional aspects of the on-road driving task (e.g., average speed, proportion of trips in different speed zones) are representative of participants’ real-world driving patterns.  相似文献   
186.
通过对浙江省工业烟粉尘排放总量和排放源现状进行分析,提出工业烟粉尘减排治理对策,对工业烟粉尘4个重点行业(水泥制造行业、火力发电行业、钢铁行业(包括炼钢、钢压延加工和黑色金属铸造行业)、纺织染整行业(包括棉印染精加工、化纤织物染整精加工和棉织造加工行业)排放源的烟粉尘减排途径和潜力进行分析测算,研究提出工业烟粉尘总量控制措施和建议。  相似文献   
187.
除尘器对颗粒物的除尘效率与颗粒物的荷电量密切相关,PM2.5等细小颗粒物由于其荷电量不足而导致其吸收效率较低,对环境造成危害。为了增加粒子的荷电量,以粒子荷电原理为理论依据,从离子电流密度和通过电凝并扩大尘粒中位径2个方面研究了电除尘电源中交流电压分量对PM2.5等细小颗粒物荷电特性的影响,得出了电除尘器电源中交流电压分量可从以上2个方面提高装置对PM2.5等微小颗粒物的荷电量,且频率越高,幅值越大,荷电效果越好,从而可以提高装置对细小颗粒物的除尘效率。  相似文献   
188.
A low-cost, high throughput bioanalytical screening method was developed for monitoring cis/trans-permethrin in dust and soil samples. The method consisted of a simple sample preparation procedure [sonication with dichloromethane followed by a solvent exchange into methanol:water (1:1)] with bioanalytical detection using a magnetic particle enzyme-linked immunosorbent assay (ELISA). Quantitative recoveries (83–126 %) of cis/trans-permethrin were obtained for spiked soil and dust samples. The percent difference of duplicate ELISA analyses was within ± 20 % for standards and ± 35 % for samples. Similar sample preparation procedures were used for the conventional gas chromatography/mass spectrometry (GC/MS) analysis except that additional cleanup steps were required. Recoveries of cis/trans-permethrin ranged from 81 to 108 % for spiked soil and dust samples by GC/MS. The ELISA-derived permethrin concentrations were highly correlated with the GC/MS-derived sum of cis/trans-permethrin concentrations with a correlation coefficient (r) of 0.986. The ELISA method provided a rapid qualitative screen for cis/trans-permethrin in soil and dust while providing a higher sample throughput with a lower cost as compared to the GC/MS method. The ELISA can be applied as a complementary, low-cost screening tool to prioritize and rank samples prior to instrumental analysis for exposure studies.  相似文献   
189.
新疆奎屯市17种落叶树种的滞尘能力研究   总被引:1,自引:0,他引:1  
对奎屯市17种落叶树种进行了滞尘能力测定。结果表明,不同类型植物滞尘能力差异显著,灌木滞尘能力大于乔木。在11种落叶乔木中,滞尘能力最强的是圆冠榆,平均滞尘能力达3.6894g/m^2;在5种落叶灌木中,滞尘能力最强的是玫瑰,平均滞尘量可达3.6581g/m^2。  相似文献   
190.
沙尘试验设备参数的测量,目前没有相关的标准和指导文件。本文给出沙尘试验设备参数测量的一般方法,主要介绍了一种沙尘浓度测量方法。  相似文献   
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