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181.
In recent years, increasing attention has been paid to the issue of driving under the influence of alcohol (DUI), especially among young people. The aims of the present study were (1) to analyse the trends of DUI, riding with a driver under influence of alcohol (RWDUI) and alcohol-related road crashes (A-rC) in a nationally representative sample of students in the period 2007–2013, (2) to assess how different drinking patterns were associated with DUI and RWDUI, (3) to evaluate other influential factors (such as gender, older siblings’ and friends’ behaviour with alcohol) on DUI and RWDUI. Data were drawn from the cross-sectional European School Survey Project on Alcohol and Other Drugs (ESPAD) carried out annually in Italy. The sample size ranged from 25,555 to 40,390 students (15–19 years old). Results were stratified for students <18 years and ≥18 years old. Although a significant decreasing trend for alcohol consumption was observed only in the younger group, a significant decrease in DUI [APC (annual percent change) −9.7 in the younger and −6.4 in the older group] and in RWDUI (APC −6.7 in the younger and −4.8 in the older group) was detected. A significant decreasing trend of A-rC was observed only in the older group (APC −3.4). Three specific drinking patterns were identified: “Drinking to Excess” (DE), “Drinking with Intoxication” (DI) and “Drinking but Not to Excess” (DNE). In both age groups, the DE pattern significantly increased the likelihood of DUI, whereas the DI pattern was negatively associated, and the DNE pattern was not associated. Different results were found for RWDUI: the DE and DI patterns where significantly associated with RWDUI, whereas the DNE pattern was negatively associated. Overall, illegal substance use, parental monitoring, peers’ and siblings’ influence were associated with DUI and RWDUI. The change in behaviour towards DUI and RWDUI suggests a cumulative effectiveness of current alcohol policies, although further actions (greater attention to social context, law enforcement, and promotion of good practice) are needed to substantially reduce alcohol-related crashes. 相似文献
182.
S. D. DANILOV A. E. GURYANOV M. A. KALLISTRATOVA I. V. PETENKO S. P. SINGAL D. R. PAHWA 《International journal of remote sensing》2013,34(2):307-312
The accurate estimation of sodar antenna parameters, back-scattering cross-section and a knowledge of acoustic absorption in the atmospheric air are needed in case structure parameters are to be computed. In the paper a simple method using a theoretical antenna directivity pattern, together with measurements of transduction characteristics of the acoustic transducer has been suggested. The method has been used for two sodars belonging to the Russian Academy (Sodar Latan-I) and the National Physical Laboratory, New Delhi, The theoretically and experimentally determined directivities of the Sodar Transducer Systems have been compared and it has been found that they coincide rather satisfactorily within the angles at which the paraboloids of sodars are seen from their respective foci. Computed thermal structure parameter values using Sodar Latan-I based on the above approach have been found to be comparable with the values computed from microthermal data collected simulaneously at the same place 相似文献
183.
高性能混凝土具有非常好的可塑性、耐久性以及强度,现已被广泛地应用于水利、建筑以及交通等领域中。本文说明了高性能混凝土对不同原材料的要求,并探究了在公路工程以及桥梁工程项目中高性能混凝土的具体应用。 相似文献
184.
以岢临高速公路施工工程为例,介绍了滑模施工设备在岢临高速公路路缘石施工中的全过程、注意事项及控制措施,并与预制安装法进行了成本对比,指出滑模施工路缘石法施工效率高、经济效益好,值得推广应用。 相似文献
185.
结合工程实践,就利路力固化剂在公路工程中应用的施工工艺进行深入探讨,从施工准备、放样、拌和、摊铺、碾压及养护等方面进行了阐述,为该类固化剂的推广应用提供了技术支撑。 相似文献
186.
Zaharah Allah Bukhsh Irina Stipanovic Giel Klanker Alan O’ Connor Andre G. Doree 《Structure and Infrastructure Engineering》2019,15(7):872-885
Bridge infrastructure managers are facing multiple challenges to improve the availability and serviceability of ageing infrastructure, while the maintenance planning is constrained by budget restrictions. Many research efforts are ongoing, for the last few decades, ranging from development of bridge management system, decision support tools, optimisation models, life cycle cost analysis, etc. Since transport infrastructures are deeply embedded in society, they are not only subject to technical requirements, but are required to meet the requirements of societal and economic developments. Therefore, bridge maintenance planning should accommodate multiple performance goals which need to be quantified by various performance indicators. In this paper, an application of Multi-Attribute Utility Theory (MAUT) for bridge maintenance planning is illustrated with a case study of bridges from the Netherlands road network. MAUT seeks to optimise multiple objectives by suggesting a trade-off among them and finally assigns a ranking to the considered bridges. Moreover, utility functions of MAUT appropriately account for the involved uncertainty and risk attitude of infrastructure managers. The main contribution of this study is in presenting a proof-of-concept on how MAUT provides a systematic approach to improve the decision-making of maintenance planning by making use of available data, accommodating multiple performance goals, their uncertainty, and preferences of infrastructure managers. 相似文献
187.
以龙背湾水电站为例,介绍了大坝主堆石料的运输要求,提出了运输干道布置的设计方案,从方案的特性及工程投资等方面进行了比选,确定了最优方案。特别介绍了采用交通洞方案的优点及应用效果。 相似文献
188.
With the pressing demand of environmentally friendly personal transportation vehicles, mobility scooters become more and more popular for the short-distance transportation. Similar to pedestrians and bicyclists, scooter riders are vulnerable road users and are expected to receive severe injuries during traffic accidents. In this research, a MADYMO model of vehicle–scooter crash scenarios is numerically set up. The model of the vehicle with the scenario is validated in pedestrian–vehicle accident investigation with previous literatures in terms of throwing distance and HIC15 value. HIC15 values gained at systematic parametric studies. Injury information from various vehicle crashing speeds (i.e. from 10 m/s to 24 m/s), angles (i.e. from 0 to 360°), scooter's speeds (i.e. from 0 m/s to 4 m/s), contact positions (i.e. left, middle and right bumper positions) are extracted, analyzed and then compared with those from widely studied pedestrian–vehicle and bicycle–vehicle accidents. Results show that the ESS provides better impact protection for the riders. Riding ESS would not increase the risk higher than walking at the same impact conditions in terms of head injury. The responsible reasons should be the smaller friction coefficient between the wheel-road than the heel-road interactions, different body gestures leading to different contact positions, forces and timing. Results may shed lights upon the future research of mobility scooter safety analysis and also the safety design guidance for the scooters. 相似文献
189.
通过对某市区主要交通干道路面沉积物理化特性的监测分析,得出研究区域路面沉积物的基本物理化学性质,包括街道灰尘的pH、有机质和其粒径分布特征.同时,还分析了不同季节路面沉积物理化特性. 相似文献
190.