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41.
临街建筑群中交通噪声的计算机模拟   总被引:3,自引:0,他引:3       下载免费PDF全文
给出了临街建筑群中纵深方向的交通噪声计算机模拟预测方法。交通干道上车流采用泊松分布和等车距车流相结合模型,考虑多种车型的不同声功率级。每辆车作为一个点声源,以几何声学方法考虑直达声和有限次反射声对测点的影响。在计算程序中只要输入车流量,车流成份,建筑群中有关巷道宽度,测点在巷子纵深方向距离及背景噪声等数据,计算机便能输出L10,L50,L98,Leq等声级值。模拟结果和实测值基本一致。  相似文献   
42.
Reliable measurements of pollutant levels in the vicinity of a toll plaza appear to be rare. In order to assess the exposure of toll booth operators to carbon monoxide, a continuous carbon monoxide monitor was installed at head height in the booth of a medium density traffic lane at the Mariannhill toll plaza, situated on a busy highway near Durban, South Africa. Measurements in excess of 500 ppmv were recorded and the high daily mean carbon monoxide concentrations may account for some of the symptoms such as headaches and general malaise that have been reported by workers in the booths. Generally, carbon monoxide levels recorded far exceed the recommended limit set by the South African authorities. These results have led to recommendations regarding the structure of new and existing toll booths to minimize the exposure of toll booth workers to adverse effects of vehicle-emitted pollutants.  相似文献   
43.
To assess the effect of changes in traffic density and fuels used for heating at the beginning of the 1990s, 1992–2005 monthly averages of PM10, SO2, NO2, NO, CO and O3 from Prague, the Czech capital, were analyzed together with long term trends in emissions of major pollutants, fuel consumption and number of vehicles registered in Prague. The data from all monitoring stations were retrieved from the database of the state automated monitoring system. Correlation coefficients between ambient monthly averaged temperature and all pollutants of concern showed distinct seasonal trends. The results showed that while SO2 and to some extent also CO concentrations dropped namely in the first half of the analyzed period (1992–1997) as a result decreased fossil fuel consumption for local heating, the behaviour of other pollutant concentrations followed a different pattern. PM10 concentrations decreased during the beginning of the 1990s but showed a sign of increase after 2000. Concentrations of ozone and NO2 did not reveal any significant change throughout the whole studied period. It can be concluded that during the studied period traditional urban sources of pollution, such as coal and oil combustion, lost their importance but were simultaneously substituted by pollutants from automotive transport (namely PM and NO2) making the problem of air quality even worse.  相似文献   
44.

Problem

Various indicators of health have been shown to be associated with traffic crash involvement. As general health is also related to absence from work, the latter variable may be more strongly related to crashes, especially for professional drivers.

Method

Bus driver absence from work was analyzed in association with their crash records. Two British samples and one Swedish sample were used.

Results

One of the British samples yielded fair correlations between crash record and absence, while for the other the effect was restricted to the first three months of driving. The Swedish data had effects in the expected direction but these were not significant.

Discussion

The use of an indirect, overall measurement of health, may be a viable method for predicting the traffic crash involvement for professional drivers, although replications are needed in larger samples and other populations.

Impact on industry

The use of absence records for the identification of at risk drivers would seem to be a simple and useful method for companies with major fleets, and it also shows the importance of promoting employee health and well being at work as a potential method of reducing the cost, not only of absenteeism, but also of crashes in company vehicles.  相似文献   
45.

Introduction

This article compares observed driving behavior in a city, a town, and a village.

Method

Unobtrusive observations were made at intersections in each residential type. Five violation types were observed: (a) not wearing a seat belt (seat belt violation); (b) not using a safety seat for a child (safety seat violation for children); (c) not using a speaker while speaking on the phone (on-phone violation); (d) failing to comply with a ‘give way’ sign (‘give way’ sign violation); and (e) stopping in an undesignated area (undesignated stop violation). It was expected that in accordance with the anonymity hypothesis that the bigger residential areas' rate of traffic violations would be higher. The effects of the residential type, drivers' gender, and age were assessed using the multiple regression model. The stepwise method of evaluation was employed. The model converged on step 3 (Adjusted R square = 0.039). Residential type and gender contributed significantly to the model. Results: Consistent with prior research, male drivers committed more violations than female drivers. Chi-square analyses were used to test the distribution of violations by the settlement types. Overall, more drivers committed violations in the two small residential areas than in the city, with 30% of city drivers, 43% of town drivers, and 51% of village drivers committing at least one violation (χ2 (2) = 37.65, p < 0.001). Moreover, in the town and the village, a combination of one or more violations was committed more often than in the city (χ2 (1) = 34.645, p < 0.001). Accordingly, more drivers committed violations in the two small settlements (48.4%) than in the city (30.6%). Possible explanations for the observed results were provided in the Discussion section.

Impact on Industry

The conclusions of this paper are that drivers in small villages tend to disobey traffic laws. Therefore, efforts have to be made in companies to take this issue in consideration while running fleets in companies located in small places far from the center.  相似文献   
46.
Introduction: Heterogeneous driving populations with many different origins are likely to have various sub-cultures that comprise of drivers with shared driver characteristics, most likely with dissimilar traffic safety cultures. An innovative methodology in traffic safety research is introduced which is beneficial for large datasets with multiple variables, making it useful for the multi-variate classification of drivers, driving attitudes and/or (risky) driving behaviours. Method: With the application of multidimensional scaling analysis (MDS), this study explores traffic safety culture in the State of Qatar using a questionnaire and investigates the similarity patterns between the questionnaire items, aiming to classify attitudes towards risky driving behaviours into themes. MDS is subsequently applied to classify drivers within a heterogeneous driving sample into sub-cultures with shared driver characteristics and different risky driving attitudes. Results: Results show that acceptance of speeding is highest among the young Arabic students and acceptance of distraction and drivers’ negligence such as phone use and not wearing a seatbelt is highest among male Arab drivers. Acceptance of extreme risk-taking like intoxicated driving and red-light running is highest among South-Asian business drivers. Conclusion: It is important and practical to understand risky behavioural habits among sub-cultures and thereby focussing on groups of drivers instead of individuals, because groups are easier to approach and drivers within sub-cultures are found to influence each other. By indicating which groups of drivers are most likely to perform specific risky driving themes, it is possible to target these groups and effectively emphasise certain subsets of risky driving behaviours during training or traffic safety education. Practical Applications: This study provides guidance for the improvement of driver education and targeted traffic safety awareness campaigns, intending to make changes to attitudes and habits within specific driver sub-cultures with the aim to improve traffic safety on the longer term.  相似文献   
47.
Introduction: While road traffic accidents and fatalities are a worldwide problem, the rates of road traffic accidents and fatalities show differences among countries. Similarly, driver behaviors, traffic climate, and their relationships also show differences among countries. The aim of the current study is to investigate the moderating effect of driving skills on the relationship between traffic climate and driver behaviors by country. (Turkey and China). Method: There were 294 Turkish drivers and 292 Chinese drivers, and they completed the Traffic Climate Scale, the Driving Skills Inventory, and the Driver Behavior Questionnaire. The moderated moderation analyses were conducted with Hayes PROCESS tool on SPSS. Results: The results showed that safety skills moderated the relationship between internal requirements and violations both in Turkey and China. Safety skills also moderated the relationship between internal requirements and errors only in China and the relationship between functionality and violations in Turkey. Perceptual-motor skills moderated the relationships between external affective demands and errors, and also the relationship between internal requirements and positive driver behaviors in Turkey. It can be inferred that driving skills has different influences on traffic climate-driver behaviors relationship in different cultures and there might be cultural differences in the evaluation of drivers’ own driving skills. Practical Applications: Among driving skills, safety skills have a more critical role to increase road safety by decreasing number of violations. Interventions to increase safety skills of drivers might be promising for road safety.  相似文献   
48.
Roadside dusts and soils were collected from various nonindustrial districts in Cincinnati, Ohio, USA, and analyzed for lead and copper contents. Results showed that the recent lead phase-down action has reduced the level of lead, but the concentrations of both metals are still higher than the background levels for normal soil. Elevated concentrations of copper in heavily traveled highways were noted, suggesting that much of the copper pollutants is probably of automotive origin. The concentration of lead was found to vary with housing age, and higher levels of contamination in the older neighborhoods were observed. This result is probably ascribable to the accumulation of residues from leaded gasoline and lead-based paint in the past and the use of coal fire for space heating in older houses.  相似文献   
49.
In this paper, a shifted power-law model, based on the wind profile model, had been supposed to simulate concentration gradient of nitrogen dioxide (NO2) with distance from a highway. Field experiments were performed for NO2 gradients from a highway in Shanghai by using passive samplers. The shifted power-law model was fitted well with experimental results of field experiments both in this study and in the literature. The results not only verified the validity of shifted power-law relationship between NO2 concentration and the distance from a highway, but also partially demonstrated that there were some significant similarities between wind profile and air pollutants concentration profile near highway. With known concentration of chosen reference point and appropriate value of the parameter k, the model could be practically applied for predicting the NO2 distributions near a highway. The methods of determining the parameter k were also discussed for further detailed studies.  相似文献   
50.
A comparative evaluation of two Gaussian-based line source models namely, California line source dispersion model version 4 and the general finite line source model, is presented. The concentrations predicted by these models are compared with background-corrected ambient concentrations measured at three different distances from a motorway and performance of both models assessed in the context of integrated transport–environment modelling for regulatory purposes.  相似文献   
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