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181.
促进我国道路交通安全建设策略的探讨   总被引:6,自引:3,他引:6  
道路交通安全是一项复杂的系统工程 ,我国的道路安全建设与国外相比有很大的差距 ,如何提高我国道路交通安全的水平是我们研究的重要课题。笔者分析了当前中国道路交通安全所面临的严峻形势 ,阐述了道路交通安全系统中三要素对系统的影响 ,结合我国实际特点 ,从系统的角度 ,提出了我国道路交通安全建设的策略 ,从而实现减少交通事故 ,达到提高中国道路交通安全水平的目的  相似文献   
182.
Management of the coastal zone for the purposes of conservation and sustainability is a well-described concept in the literature. This paper describes the importance of modelling various forms of maritime traffic as an intrinsic element of this process. Effective use of GIS in this context implies extensive data acquisition and cleaning, vessel path simulation, traffic density maps, and incident (spills or accidents) distribution when applicable. Risks can be determined by evaluating detrimental occurrences relative to exposure levels. Effective visualization and quantitative analyses can then be fruitfully applied to various coastal zone management spheres, such as oceans use planning, emergency response planning, and marine protected area delineation.  相似文献   
183.
The most important constituents of traffic exhaust are carbon monoxide, nitrogen oxides, volatile organic compounds, polycyclic hydrocarbons and lead. Satisfactory analytical methods are available for measuring these compounds, but the required expenditure in their application to air pollution studies is quite different. Due to correlations between the concentrations of several exhaust components in road air conclusions regarding the expected level of some substances can be drawn by measurement of another emitted compound. But the selection of indicator compounds must be made under the aspect of the source‐specific relationship of emitted substances. The temporal and spatial distribution of air pollutants in street air is affected by traffic emissions more than by meteorological conditions. “Fingerprints”; of typical organic gaseous components of traffic exhaust also were found in residential areas.  相似文献   
184.
智能交通与中国的交通安全   总被引:3,自引:4,他引:3  
在交通运输中 ,安全是最重要的因素。近年来 ,中国交通运输事业的快速发展 ,给人民的生活带来诸多便利 ,但当前的交通安全状况却不容乐观 ,交通事故频繁发生 ,事故死亡人数逐年上升。智能交通系统是一个高科技集成系统 ,它综合运用各种高新技术于整个交通管理系统之中 ,可以系统、全面、高效地提高交通运输的安全性。笔者研究了我国的交通安全问题 ,尤其是公路交通安全问题 ,阐明了如何应用智能交通系统 ,有效地减少交通事故 ,改善交通安全状况 ;指出了我国发展智能交通对于改善交通安全 ,解决交通安全问题的重要意义并展望了我国发展智能交通的前景  相似文献   
185.
交通事故预测分析   总被引:7,自引:2,他引:7  
运用模糊图、灰色系统、非线性回归、随机过程和安全系统工程的理论与方法,进行交通事故预测分析。给出了交通事故预测分析的双向模糊图模型、灰色马尔可夫预测模型及非线性回归模型。模型运行结果可为交通事故的预防和交通安全管理提供科学依据  相似文献   
186.
A growing empirical evidence base identifies environmental noise exposure as an important health problem. While the health effects depend for a great part on personal noise sensitivity and contextual factors, in environmental policy, generic noise standards and procedures based on objective sound levels are used. In this article, the relation between objective and subjective noise exposure variables is further explored by carrying out a residents’ survey in a highly noise polluted area along two highways south of the city centre of Ghent, Belgium. The survey results show only a weak correlation between objective and subjective exposure variables, with both variables demonstrating different associations with the respondents’ background characteristics. While lower-educated and lower-income people are generally higher exposed according to the models, they do not report a higher subjective exposure. People who have been living longer in the area are not necessarily higher exposed according to the models but do report a higher subjective exposure. Most strikingly, owners of a comfortable detached house report a higher subjective exposure than renters of an apartment or small house, while the latter group is significantly higher exposed according to the models. The results support a plea for the joint evaluation of both objective and subjective noise exposure variables in environmental policy and environmental assessments. In addition, the results argue for specific attention for noise exposure of socio-economically vulnerable people and the establishment of a shared knowledge base on noise exposure with both objective and subjective information.  相似文献   
187.
随着社会生活不断进步,旅游作为一种新的精神生活方式,使人们之间的交往不再局限于两点之间。人员的相互流动加强了彼此的了解,但也衍生出很多实际问题,环境保护也因此逐渐受到人们的重视,生态旅游的提出正是基于这样的现状。本文从生态旅游的角度来分析西部旅游与交通的关系,试图找出解决对策,真正实现落后地区的可持续发展。  相似文献   
188.
A previous study has shown that the useful visual field deteriorates in a simulated road traffic situation as a function of the driver’s age and of the vehicle’s speed under monotonous conditions [Rogé, J., Pébayle, T., Lambilliotte, E., Spitzenstetter, F., Giselbrecht, D., Muzet, A., 2004. Influence of age, speed and duration of monotonous driving task in traffic on the driver’s useful visual field. Vision Research 44 (23), 2737–2744]. The aim of this new experiment is to study the effects of traffic density and age on the useful visual field of the driver during a simulated driving task with controlled traffic characteristics (speed, number of cars) for all participants. In total, 10 young drivers (m = 28.2 years) and 10 older drivers (m = 51.2 years) followed a car in road traffic at an average speed of 126 km h−1 during two 2 h sessions corresponding to two conditions of traffic (light traffic, with five vehicles around the participant; and heavy traffic, with nine vehicles). While following this vehicle, the driver had to detect changes in the colour of a signal located in the central part of his or her visual field and a signal that appeared at different eccentricities on the rear lights of other vehicles in the traffic. Analysis of the data indicated that age interacted with the location of the peripheral signal and density of traffic interacted with the duration of driving. The implications of these results are discussed in terms of road safety and in terms of models of deterioration of the useful visual field (general interference and tunnel vision).  相似文献   
189.
本文利用光学中的Hugens-Fresnl原理和Kir-chof近似理论,建立了由点声源组成的随机车辆流模型,探讨声波通过屏障间狭缝的衍射,从而确定交通噪声对临街建筑群中某测点的贡献  相似文献   
190.
Introduction: Speeding is a crucial risk factor for pedestrian safety because it shortens reaction time while increasing the impact force in collisions. Various types of traffic calming measures to prevent speeding have been devised. A speed hump—a raised bump installed in the pavement—has been widely used for this purpose. Method: To evaluate the effectiveness of speed humps, the speed profiles of vehicles passing speed humps were analyzed along with pedestrian crash records near speed humps. Results: The speed profiles showed that vehicles gradually diminished their speeds starting 30 m ahead of speed humps and, immediately after passing the humps, accelerated to regain their original speeds within a distance of 30 m. This speed reduction effect is substantial on both local and major roads: 18.4% and 24.0% reduction in speeds, respectively. The analysis of pedestrian crash records revealed that, inside the zones of speed reduction effect near speed humps (i.e., ±30 m from speed humps), fewer pedestrian crashes per roadway distance occurred and pedestrian injuries were less severe, compared with events outside the effect zones. This safety improvement was greater on major roads than local roads. Practical Applications: This work finds that the speed reductions that occurred near speed humps were gradual and influential ±30 m from their locations, suggesting that the hump installations should be close enough to the pedestrian crossings. It is noteworthy that, albeit that speed humps are more prevalent on local roads, the benefits of speed reduction effects from speed humps were more pronounced on major roads than on local roads. Therefore, speed humps on major roads can be considered a more effective measure for pedestrian safety.  相似文献   
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