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1.
A before and after hedonic model is used to determine the property value impacts on properties already served by the transit system caused by extensions to Bogotá’s bus rapid transit system. Asking prices of residential properties belonging to an intervention area (N = 1407 before, 1570 after) or a control area (N = 267 before, 732 after) and offered for sale between 2001 and 2006 are used to determine capitalization of the enhanced regional access provided by the extension. Properties offered during the year the extension was inaugurated and in subsequent years have asking prices that are between 13% and 14% higher than prices for properties in the control area, after adjusting for structural, neighborhood and regional accessibility characteristics of each property. Furthermore, the appreciation is similar for properties within 500 m and properties between 500 m and 1 km of the BRT.  相似文献   

2.
The paper intends to analyse the different attitudes of residents in urban areas in regard to annoyance induced by traffic noise, account taken of the effects of the street configuration and of the presence of specific public transport modes in the definition of the dose-response curves.People’s annoyance was investigated through a campaign of noise and traffic measurements and an epidemiological survey, administered to a sample of 830 residents in the buildings close to the measurement points.An ordinal regression model taking into account environmental and urban characteristics was used to identify a dose-response relationship. The cumulative probabilities allowed to define two cut points on the dose-response curves (60 and 75 dB(A)), grouping people in three classes and making the representation of the dose-response relationships different from those traditionally defined that use only the percentage of highly annoyed people.The results show different people’s attitudes towards the annoyance in the urban sites while the dose-response relationship shows that the correlation between annoyance and noise is low. For the same value of day equivalent level, 10% more people are annoyed in L sections (broad streets) than in U sections (narrow streets). Furthermore, all the dose-response curves show a higher sensitivity of people living in L sections; this difference can be measured as a shift of about 4 dB(A). Noise levels are, arguably, a useful indicator, but they are not reliable enough to define the discomfort of the residents, while the site characteristics could shed light on annoyance variability.  相似文献   

3.
4.
This paper compares monetary values for aircraft noise disturbance and annoyance derived using hedonic price and stated preference methods in the same sample areas and over the same sampling time periods. The hedonic price method compares house prices in residential areas across a range of aircraft noise sound levels. The statistical power can be compromised by the many other variables which have significant and often greater effects on prices and because only small fractions of the overall housing stock are bought and sold at any one time. The stated preference method on the other hand, by requiring study participants to trade hypothetical money against hypothetical noise, is entirely based on subjective opinion. It seems that neither method is entirely satisfactory, but there are strong positive correlations between the ratios of aggregated stated preference values to weighted average house prices and LAeq, 16 h and similar noise metrics suggesting sufficient underlying similarities  相似文献   

5.
This paper deals with the value of supplemental aircraft noise information in the form of combining aircraft movement numbers and noise levels to assist airport neighbours in understanding airport noise. To analyse the socio-spatial interaction of annoyance with, and interference by, aircraft noise, an alternative is recommended, namely the number of noise events above selected noise levels so that laypeople can better understand the extent of noise. The research is based on a questionnaire survey of households affected by aircraft noise around OR Tambo International Airport near Johannesburg. The results indicate that levels of annoyance and disturbance across a number of normal household activities are positively related to the number of noise events recorded, irrespective of noise levels above 60 dB.  相似文献   

6.
Vehicle-related countermeasures to sustain driver’s alertness might improve traffic safety. The purpose of this study was to investigate the effects of somatosensory 20 Hz mechanical vibration, applied to driver’s right heel during prolonged, simulated, monotonous driving, on their cardiovascular hemodynamic behavior. In 12 healthy young male volunteers, during 90-min periods of simulated monotonous driving, we compared cardiovascular variables during application of 20 Hz mechanical vibration with 1.5 Hz as a control and with no vibration. The parameters recorded were indices of key cardiovascular hemodynamic phenomena, i.e., blood pressure as an indicator of stress, cardiac output, and total peripheral-vascular resistance. The principle results were that all conditions increased the mean blood pressure, and elicited a vascular-dominant reaction pattern typically observed in monotonous driving tasks. However, mean blood pressure and total peripheral-vascular resistance during the monotonous task were significantly decreased in those receiving the 20 Hz vibration as compared with 1.5 Hz and with no vibration. The observed differences indicate the cardiovascular system being more relieved from monotonous driving stress with the 20 Hz vibration. The major conclusion is that applying 20 Hz mechanical vibration to the right heel during long-distance driving in non-sleepy drivers could facilitate more physiologically appropriate status for vehicle operation and could be a potential vehicular countermeasure technology.  相似文献   

7.
Driver sleepiness contributes to a considerable proportion of road accidents, and a fit-for-duty test able to measure a driver’s sleepiness level might improve traffic safety. The aim of this study was to develop a fit-for-duty test based on eye movement measurements and on the sleep/wake predictor model (SWP, which predicts the sleepiness level) and evaluate the ability to predict severe sleepiness during real road driving. Twenty-four drivers participated in an experimental study which took place partly in the laboratory, where the fit-for-duty data were acquired, and partly on the road, where the drivers sleepiness was assessed. A series of four measurements were conducted over a 24-h period during different stages of sleepiness. Two separate analyses were performed; a variance analysis and a feature selection followed by classification analysis. In the first analysis it was found that the SWP and several eye movement features involving anti-saccades, pro-saccades, smooth pursuit, pupillometry and fixation stability varied significantly with different stages of sleep deprivation. In the second analysis, a feature set was determined based on floating forward selection. The correlation coefficient between a linear combination of the acquired features and subjective sleepiness (Karolinska sleepiness scale, KSS) was found to be R = 0.73 and the correct classification rate of drivers who reached high levels of sleepiness (KSS  8) in the subsequent driving session was 82.4% (sensitivity = 80.0%, specificity = 84.2% and AUC = 0.86). Future improvements of a fit-for-duty test should focus on how to account for individual differences and situational/contextual factors in the test, and whether it is possible to maintain high sensitive/specificity with a shorter test that can be used in a real-life environment, e.g. on professional drivers.  相似文献   

8.
In recent years, several studies show that people who live, work or attend school near the main roadways have an increased incidence and severity of health problems that may be related with traffic emissions of air pollutants. The concentrations of near-road atmospheric pollutants vary depending on traffic patterns, environmental conditions, topography and the presence of roadside structures. In this study, the vertical and horizontal variation of nitrogen dioxide (NO2) and benzene (C6H6) concentration along a major city ring motorway were analysed. The main goal of this study is to try to establish a distance from this urban motorway considered “safe” concerning the air pollutants human heath limit values and to study the influence of the different forcing factors of the near road air pollutants transport and dispersion. Statistic significant differences (p = 0.001, Kruskal–Wallis test) were observed between sub-domains for NO2 representing different conditions of traffic emission and pollutants dispersion, but not for C6H6 (p = 0.335). Results also suggest significant lower concentrations recorded at 100 m away from roadway than at the roadside for all campaigns (p < 0.016 (NO2) and p < 0.036 (C6H6), Mann–Whitney test). In order to have a “safe” life in homes located near motorways, the outdoor concentrations of NO2 must not exceed 44–60.0 μg m−3 and C6H6 must not exceed 1.4–3.3 μg m−3. However, at 100 m away from roadway, 81.8% of NO2 receptors exceed the annual limit value of human health protection (40 μg m−3) and at the roadside this value goes up to 95.5%. These findings suggest that the safe distance to an urban motorway roadside should be more at least 100 m. This distance should be further studied before being used as a reference to develop articulated urban mobility and planning policies.  相似文献   

9.
Cities are complex systems, where related Human activities are increasingly difficult to explore within. In order to understand urban processes and to gain deeper knowledge about cities, the potential of location-based social networks like Twitter could be used a promising example to explore latent relationships of underlying mobility patterns. In this paper, we therefore present an approach using a geographic self-organizing map (Geo-SOM) to uncover and compare previously unseen patterns from social media and authoritative data. The results, which we validated with Live Traffic Disruption (TIMS) feeds from Transport for London, show that the observed geospatial and temporal patterns between special events (r = 0.73), traffic incidents (r = 0.59) and hazard disruptions (r = 0.41) from TIMS, are strongly correlated with traffic-related, georeferenced tweets. Hence, we conclude that tweets can be used as a proxy indicator to detect collective mobility events and may help to provide stakeholders and decision makers with complementary information on complex mobility processes.  相似文献   

10.
This paper presents the characterization of air quality monitored at near field region (NFR) and far field region (FFR) of a national highway located at an industrial complex. The pollutants such as PM10, SO2 and NO2 were monitored in two campaigns (11th September to 18th October 2012 and 18th January to 17th February 2013). The 24 h average PM10 concentration at NFR and FFR were found to be 86.69 ± 18.56 μg/m3; 73.16 ± 16.21 μg/m3 and 89.44 ± 18.69 μg/m3; 81.91 ± 16.42 μg/m3, respectively during first and second campaign. In both the campaigns PM10, SO2 and NO2 concentration at NFR was higher than FFR. The chemical characterization of PM10 at NFR and FFR indicated the abundance of major elements such as Na (NFR = 30% and FFR = 32%), Ca (NFR = 12% and FFR = 14%) and ions namely NO3 (NFR = 71% and FFR = 68%) and NH3+ (NFR = 15% and FFR = 19%). Further, at FFR, SO42 and NO3 were found to be 18% and 35% higher than NFR indicating the conversions of SO2 and NO2 concentration into secondary particles. The measured SO2 and NO2 concentrations were 23 and 21% lower at FFR when compared to NFR confirms the secondary formation.The CALPUFF, EPA regulatory model was set up to understand the dynamics of air pollutants at the industrial complex. The predicted PM10, SO2 and NO2 concentrations at NFR and FFR were found to be 32.31 ± 1.56 μg/m3 and 31.35 ± 1.27 μg/m3; 0.37 ± 0.21 μg/m3 and 0.06 ± 0.04 μg/m3; 12.83 ± 6.55 μg/m3 and 4.67 ± 2.77 μg/m3, respectively. The model showed moderate predictions for PM10 (R2 = 0.44–0.52), SO2 (R2 = 0.41–0.51) and NO2 (R2 = 0.45–0.61) concentrations.  相似文献   

11.
In Norway, as in many countries, a political goal is to increase bicycle use, and the e-bike is promising in this respect. However, concerns have been raised about mode-share effects. It has been argued that if the e-bike’s only function is in cycling becoming cycling with electric assistance, there would be no benefit to either the environment or public health. Little is yet known about the use of the e-bike, or of its potential in reducing motorized travel. In the current study, 66 randomly selected participants were given an e-bike to use for a limited period of time and the results compared with those of a control group (N = 160). E-bike cycling trips increased from 0.9 to 1.4 per day, distance from 4.8 km to 10.3 km and, as a share of all transport, from 28% to 48%, whereas with the control group there was no increase in cycling. The effect of the e-bike increased with time, indicating a learning effect among users, and was greater for female than for male cyclists. There were no differences with age. Overall, the results suggest that the e-bike is indeed practical for everyday travel.  相似文献   

12.
The purpose of this study is to assess differences in the levels of cost efficiency of bus lines operated under competitively tendered contracts and performance-based negotiated contracts. Following the revision of the Swiss railways act in 1996, regional public authorities were given the choice between two different contractual regimes to procure public passenger transport services. We directly compare the impact of competitive tendering and performance-based negotiation by applying a stochastic frontier analysis to the complete dataset of bus lines (n = 630) operated by the main Swiss company (Swiss Post) at the same time (in 2009) throughout the country. The overall results show that the differences in the levels of cost efficiency between the two contractual regimes are not significant. Our findings are in line with recent evidence of cost convergence between competitive tendering and performance-based negotiation, and suggest that the practice of using both contractual regimes is challenging for the operators in terms of competitive pressure. The threat of competitive tendering may have a disciplining effect on negotiation since it prevents bus companies from bargaining inadequate rents and inducing asymmetric information advantages.  相似文献   

13.
CO, CO2, NOx and HC emissions of two stroke-powered tricycles in Metro Manila are examined using an instantaneous emissions model. Results show that fuel consumption and HC emissions in middle class residential areas and main roads are similar but lower than levels in low income residential areas. On the average, tricycles in Metro Manila consume 24.41 km/l of fuel and produces 9.5, 9.7, 40.5 and 0.07 g/km of HC, CO, CO2 and NOx, respectively. They fail to satisfy HC, CO and NOx emission limits set by reference standards in the Philippines and other Asian countries. They produce greater HC and CO emissions than gasoline fueled private cars and diesel powered public jeepneys, taxis and buses on a per passenger-km basis but significantly lower NOx emissions. Tricycles account for 15.4% of the total HC emissions from mobile sources in the metropolis while their contributions to CO, CO2 and NOx are minimal.  相似文献   

14.
Surface soil (0–10 cm) samples from 60 sampling sites along the length of railway tracks on the territory of Srem (the western part of the Autonomous Province of Vojvodina, itself part of Serbia) were collected and analyzed for seven polychlorinated biphenyls (PCBs) and ten heavy metals in order to see how the distance from the railroad affects the concentration of some organic and inorganic pollutants in the soil. Samples were taken at a distance of 0.03–4.19 km from the railway. For the soil extraction was used USEPA 3540S method. The extracts were purified on a silica-gel column (USEPA 3630C). The analysis of the extracts was performed by gas chromatography with tandem mass spectrometry. PCBs were not detected only at two locations. Mean total concentration of PCBs for all other sampling locations was 0.0043 ppm dry weight (dw) with a range of 0.0005–0.0227 ppm dw. According to values of Nemerow pollution index Cu, Co, Zn and Ni were the most ubiquitous heavy metals in the area near railroad. Based on these results, it can be said that railway transport is a potential source of PCBs and some heavy metals.  相似文献   

15.
In China, the construction and monitoring of wildlife crossing structures is uncommon. Mountainous area occupies two-thirds area of China. A lot of tunnels (similar to overpasses in developed countries), bridges, and culverts (similar to underpasses) are constructed along highways. In general, these structures are multifunctional, including wildlife migration. However, studies on monitoring these potential crossing structures are almost vacant. Taking two highways in Changbai Mountain area as case studies, infra-red camera trapping and snow tracking were used to investigate the efficiency of tunnels, bridges and culverts on the highways. A total of 13 medium and large-sized wildlife species crossed highway through tunnels, bridges and culverts. One third of species were Chinese national protective species, and almost all species were present within 500 m from Ring Changbai Mountain Scenic highway used bridges and culverts to cross this highway. The tunnel along the expressway (length = 1000 m) and the bridges along the highway (width > 8 m) have been important passages for ungulates, Eurasian red squirrels (Sciurus vulgaris), yellow throated martens (Martes flavigula) and sables (Martes zibellina). Different species preferred to different types of structures, although most species preferred to bridges and tunnels. We suggest that short fences should be set around the bridges and culverts to guide animals to cross the passages, especially for ungulates. Monitoring programs of uses of crossing structures by wildlife should be conducted for at least 2 months to catch most species activity.  相似文献   

16.
The transportation system is one of the main sectors with significant climate impact. In the U.S. it is the second main emitter of carbon dioxide. Its impact in terms of emission of carbon dioxide is well recognized. But a number of aerosol species have a non-negligible impact. The radiative forcing due to these species needs to be quantified. A radiative transfer code is used. Remote sensing data is retrieved to characterize different regions. The radiative forcing efficiency for black carbon are 396 ± 200 W/m2/AOD for the ground mode and 531 ± 190 W/m2/AOD for the air transportation, under clear sky conditions. The radiative forcing due to contrail is 0.14 ± 0.06 W/m2 per percent coverage. Based on the forcing from the different species emitted by each mode of transportation, policies may be envisioned. These policies may affect demand and emissions of different modes of transportation. Demand and fleet models are used to quantify these interdependencies. Depending on the fuel price of each mode, mode shifts and overall demand reduction occur, and more fuel efficient vehicles are introduced in the fleet at a faster rate. With the introduction of more fuel efficient vehicles, the effect of fuel price on demand is attenuated. An increase in fuel price of 50 cents per gallon, scaled based on the radiative forcing of each mode, results in up to 5% reduction in emissions and 6% reduction in radiative forcing. With technologies, significant reduction in climate impact may be achieved.  相似文献   

17.
In 2008 the regional government of Catalonia (Spain) reduced the maximum speed limit on several stretches of congested urban motorway in the Barcelona metropolitan area to 80 km/h, while in 2009 it introduced a variable speed system on other stretches of its metropolitan motorways. We use the differences-in-differences method, which enables a policy impact to be measured under specific conditions, to assess the impact of these policies on emissions of NOx and PM10. Empirical estimation indicate that reducing the speed limit to 80 km/h causes a 1.7–3.2% increase in NOx and 5.3–5.9% in PM10. By contrast, the variable speed policy reduced NOx and PM10 pollution by 7.7–17.1% and 14.5–17.3%. As such, a variable speed policy appears to be a more effective environmental policy than reducing the speed limit to a maximum of 80 km/h.  相似文献   

18.
Road traffic noise models are fundamental tools for designing and implementing appropriate prevention plans to minimize and control noise levels in urban areas. The objective of this study is to develop a traffic noise model to simulate the average equivalent sound pressure level at road intersections based on traffic flow and site characteristics, in the city of Cartagena de Indias (Cartagena), Colombia. Motorcycles are included as an additional vehicle category since they represent more than 30% of the total traffic flow and a distinctive source of noise that needs to be characterized. Noise measurements are collected using a sound level meter Type II. The data analysis leads to the development of noise maps and a general mathematical model for the city of Cartagena, Colombia, which correlates the sound levels as a function of vehicle flow within road intersections. The highest noise levels were 79.7 dB(A) for the road intersection María Auxiliadora during the week (business days) and 77.7 dB(A) for the road intersection India Catalina during weekends (non-business days). Although traffic and noise are naturally related, the intersections with higher vehicle flow did not have the highest noise levels. The roadway noise for these intersections in the city of Cartagena exceeds current limit standards. The roadway noise model is able to satisfactorily predict noise emissions for road intersections in the city of Cartagena, Colombia.  相似文献   

19.
We construct consumer-informed estimates of residential access to vehicle charging to guide understanding of plug-in electric vehicle demand, use, and energy impacts. Using a web-based survey, study 1 estimates that about half of new car-buying US households park at least one vehicle within 25 ft of a Level 1 (110/120 V) electrical outlet at home. Study 2 estimates that just under one-third of new car-buying households in San Diego County have access to Level 2 (220/240 V) charging. Further, 20% of the sample are both able and willing to install Level 2 PEV recharging infrastructure at the prices examined.  相似文献   

20.
Aircraft noise affects human health and welfare. One method US airports use to mitigate the impact of noise on nearby residents is through sound insulation and residential land acquisition projects. Costs of residential insulation and acquisition projects are taken from federal grant summaries while the benefits of noise reduction are calculated as the combined willingness-to-pay for abatement and direct and indirect costs of illness from hypertension, myocardial infarction, and stroke. We show that the average cost of sound insulation projects is $15,600 per person affected while that of land acquisition is $48,900 per person affected. We find that for only in 15% of projects do the benefits to residents from willingness-to-pay for reduction and reduced risk of mortality and morbidity exceed the costs of sound insulation for residences exposed to 65 dB Day Night Level (DNL) of noise. Our estimates suggest that noise insulation projects are more cost-effective than fleet wide mandatory aircraft retirement.  相似文献   

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