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Background Road traffic is the most significant source of urban air pollution. PM 2.5 is the air pollutant whose health effects have been most closely studied, and is the variable most commonly used as a proxy indicator of exposure to air pollution, whereas evidence on NO 2 concentrations per se is still under study. In the case of Spain, there are no specific updated studies which calculate short-term NO 2 -related mortality. Objective To quantify the relative risks (RRs) and attributable risks (ARs) of daily mortality associated with NO 2 concentrations recorded in Spain across the study period, 2000–2009; and to calculate the number of NO 2 -related deaths. Material and methods We calculated daily mortality due to natural causes (ICD-10: A00 R99), circulatory causes (ICD-10: I00 I99) and respiratory causes (ICD-10: J00 J99) for each province across the period 2000–2009, using data supplied by the National Statistics Institute. Mean daily NO 2 concentrations in μg/m 3 for each provincial capital were furnished by the Ministry of Agriculture & Environment, along with the equivalent figures for the control pollutants (PM 10 ). To estimate RRs and ARs, we used generalised linear models with a Poisson link, controlling for maximum and minimum daily temperature, trend of the series, seasonalities, and the autoregressive nature of the series. A meta-analysis with random effects was used to estimate RRs and ARs nationwide. Results The overall RRs obtained for Spain, corresponding to increases of 10 μg/m 3 in NO 2 concentrations were 1.012 (95% CI: 1.010 1.014) for natural-cause mortality, 1.028 (95% CI: 1.019 1.037) for respiratory-cause mortality, and 1.016 (95% CI: 1.012 1.021) for circulatory-cause mortality. This amounted to an annual overall 6085 deaths (95% CI: 3288 9427) due to natural causes, 1031 (95% CI: 466 1585) due to respiratory causes, and 1978 (95% CI: 828 3197) due to circulatory causes. Conclusion By virtue of the number of cities involved and the nature of the analysis performed, with quantification of the RRs and ARs of the short-term impact of NO 2 on daily mortality in Spain, this study provides an updated estimate of the effect had by this type of pollutant on causes of mortality, and constitutes an important basis for reinforcing public health measures at a national level. [ABSTRACT FROM AUTHOR]

The article presents information on economic and financial analysis for upgrading infrastructures of traffic controlsystem in rail system. A study of an analysis o f benefits-costs for Spain's high-speed railways showed positive results. Another study also estimated the benefits through a set of shadow prices used in the Delhi Metro.

Abstract: Many cities in Europe have difficulties to meet the air quality standards set by the European legislation, most particularly the annual mean Limit Value for NO2. Road transport is often the main source of air pollution in urban areas and therefore, there is an increasing need to estimate current and future traffic emissions as accurately as possible. As a consequence, a number of specific emission models and emission factors databases have been developed recently. They present important methodological differences and may result in largely diverging emission figures and thus may lead to alternative policy recommendations. This study compares two approaches to estimate road traffic emissions in Madrid (Spain): the COmputer Programme to calculate Emissions from Road Transport (COPERT4 v.8.1) and the Handbook Emission Factors for Road Transport (HBEFA v.3.1), representative of the ‘average-speed’ and ‘traffic situation’ model types respectively. The input information (e.g. fleet composition, vehicle kilometres travelled, traffic intensity, road type, etc.) was provided by the traffic model developed by the Madrid City Council along with observations from field campaigns. Hourly emissions were computed for nearly 15 000 road segments distributed in 9 management areas covering the Madrid city and surroundings. Total annual NOX emissions predicted by HBEFA were a 21% higher than those of COPERT. The discrepancies for NO2 were lower (13%) since resulting average NO2/NOX ratios are lower for HBEFA. The larger differences are related to diesel vehicle emissions under “stop & go” traffic conditions, very common in distributor/secondary roads of the Madrid metropolitan area. In order to understand the representativeness of these results, the resulting emissions were integrated in an urban scale inventory used to drive mesoscale air quality simulations with the Community Multiscale Air Quality (CMAQ) modelling system (1 km2 resolution). Modelled NO2 concentrations were compared with observations through a series of statistics. Although there are no remarkable differences between both model runs, the results suggest that HBEFA may overestimate traffic emissions. However, the results are strongly influenced by methodological issues and limitations of the traffic model. This study was useful to provide a first alternative estimate to the official emission inventory in Madrid and to identify the main features of the traffic model that should be improved to support the application of an emission system based on “real world” emission factors. [Copyright &y& Elsevier]

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An adequate enforcement process is essential to make road traffic fines effective. Automatising such process is intended to provide such effectiveness. However, current enforcement practices do not achieve this goal, as they usually have weaknesses regarding the reliable identification of the offender, the immediacy of feedback after the violation and the completeness of offence description. Intelligent Transportation Systems (ITSs) technologies may be introduced to contribute to these issues. To enable such integration, a complete model of this process must be built. Based on the VERA2 model and the Spanish traffic legislation, in this work an enhanced model is proposed that identifies the stakeholders, the process entities, the data at stake and their interchanges. Its suitability to represent current enforcement systems (particularly the Spanish ESTRADA and the French CSA) is evaluated. Furthermore, based on this model, the integration of the ITS-related technologies is analysed, as well as their suitability compared with current approaches. [ABSTRACT FROM AUTHOR]

This study assessed the inaccuracy of the traffic estimates for toll motorway concessions in Spain. It was found that the estimates conducted by both the government and the concessionaire showed a significant bias towards overestimating traffic. The level of overestimation in Spain is even greater than that reported by other studies based on worldwide data. The notorious levels of overestimation entail severe burdens to the economics of the concessionaires that often prompt renegotiations of the contracts, which are often accepted by the government. These renegotiations usually end up with toll changes or extension of the concession terms, which have to be ultimately borne by future motorway users. It is postulated herein that the bias towards overestimating traffic in toll motorways in Spain is mostly caused by strategic issues rather than by modelling errors. [ABSTRACT FROM AUTHOR]

Abstract: At the beginning of the 21st century, the punishment strategies used by the Spanish administration were considerably hardened to achieve a reduction in road accidents. This hardening could also be seen in the mass-media public advertising campaigns, with a marked shift from gentle messages to threat-based advertisements. The goal of this study is to evaluate the effectiveness of this radical change in terms of main road accident indicators and the time that the effects last using multivariate unobserved component models set up in a state space framework applied to monthly series for the 1980–2008 period. The main conclusion is that the effect on reducing road accidents is no greater when citizens are subjected to a greater level of threats in advertising campaigns than would on average be achieved using campaigns with a low level of threats. Secondly, the impact of bloody advertising in Spain is limited to the most serious accidents, those that cause deaths, either on highways or in built-up areas. Moreover, the positive effects progressively decrease as the average lifespan for significant effects of medium and high level campaigns on deaths on highways or in built-up areas was 8months and almost 12days. The results show that a reduction in numbers of deaths and injuries is always achieved when the level of harshness in the messages is increased after a period of several years of mild advertising. [Copyright &y& Elsevier]

Abstract: Distinguishing between traffic generated exclusively from the expansion of the road network (induced demand) and that resulting from other demand factors is of crucial importance to properly designed transport policies. This paper analyzes and quantifies the induced demand for road transport for Spain’s main regions from 1998 to 2006, years that saw mobility in Spain attain its highest growth rate. The lack of research in this area involving Spain and the key role played by the sector, given its high level of energy consumption and the negative externalities associated with it (accidents, noise, traffic congestion, emissions, etc.), endow greater relevance to this type of research. Based on a Dynamic Panel Data (DPD) reduced-form model, we apply alternative approaches (fixed and random effects and GMM-based methods) for measuring the induced demand. The results obtained provide evidence for the existence of an induced demand for transport in Spain, though said results vary depending on the estimating method employed. [Copyright &y& Elsevier]

Abstract: This paper presents a summary of the results obtained from the particulate matter (PM) data collected over the 1999–2008 period from representative sites of the Madrid air basin (an urban traffic site, an urban background site and a rural site) which is located in the centre of Spain. A number of PM10 and PM2.5 filters were obtained with high volume samplers and cut-off inlets and chemically analyzed. Pollutants recorded in this area at the Air Quality monitoring stations were also analyzed. The influence of the atmospheric transport scenarios on the levels of PM was investigated by means of atmospheric back-trajectories, satellite imagery and meteorological synoptic charts. Source apportionment studies were performed to characterize the main PM sources whenever was possible. Their contributions to bulk PM levels showed clear spatial patterns, linked to characteristic meteorological scenarios. [Copyright &y& Elsevier]

Taking advantage of the regulatory framework of the European Single Sky being developed in Europe, Spain has begun a process of liberalization of air traffic services that could lead to strategic changes in the development of air transport. A series of legislative elements has been put in place to make this possible. Although this regulatory framework opens the way for liberalization, the strategic nature of the sector, and the necessity of guaranteeing continuity of service and safety, means that there are some restrictions or prior conditions. This will act as a significant barrier to entry for new providers. [ABSTRACT FROM AUTHOR]

Abstract: In one of the very first papers on traffic flow theory back in 1952, Wardrop presented the difference between the space mean speed (SMS) and the time mean speed (TMS) of a group of traveling vehicles, and derived a relationship suitable for estimating TMS, given SMS and the speed variance over SMS. As time goes by, traffic practitioners have tended towards computing TMS instead of SMS, mainly when using double loop detectors, and nowadays this is the usual practice in traffic management centers. Therefore, the useful relationship between TMS and SMS should go the other way around in relation to Wardrop’s. Recently, the complementary relationship, suitable for estimating SMS from TMS and the speed variance over TMS, has been proved. However this is not enough, as speed variance is usually not available. The present paper develops a probabilistic method to estimate SMS from TMS without the previous knowledge of speed variance and only using the usual time aggregations of double loop detector data. The main assumption of the method – the normality of vehicle speed distribution – is discussed and a formulation to obtain the expected error of the estimation is derived. The results obtained with test data from the AP-7 highway, near Barcelona in Spain, show that the developed methodology is able to estimate SMS with an average relative error as low as 0.5%. [ABSTRACT FROM AUTHOR]

Abstract: Traffic data obtained in the field usually have some errors. For instance, traffic volume data on the various links of a network must be consistent and satisfy flow conservation, but this rarely occurs. This paper presents a method for using fuzzy optimization to adjust observed values so they meet flow conservation equations and any consistency requirements. The novelty lies in the possibility of obtaining the best combination of adjusted values, thereby preserving data integrity as much as possible. The proposed method allows analysts to manage field data reliability by assigning different ranges to each observed value. The paper is divided into two sections: the first section explains the theory through a simple example of a case in which the data is equally reliable and a case in which the observed data comes from more or less reliable sources, and the second one is an actual application of the method in a freeway network in southern Spain where data were available but some data were missing. [ABSTRACT FROM AUTHOR]

This paper proposes a methodology to determine the optimum maintenance frequencies for the components of an electric railway overhead contact line system. This methodology is aimed at improving the reliability and availability of each component within its operational context and calculates the maintenance frequencies according to the criticality of each component, the importance of the area in which they are installed, and the component performance. The available maintenance team resources are also taken into account in order to optimize the frequencies and make them feasible for the maintenance team. The proposed methodology uses statistical and optimization tools to take advantage of the information obtained through the careful analysis of the historical data related to the system performance, which allows an objective determination of appropriate maintenance frequencies. Furthermore, it allows establishing the frequencies in a dynamic way through a feedback process. To prove the usefulness of the proposed methodology, a case study is presented in which maintenance frequencies of some components of the overhead contact line of the Spanish railway network are determined. [ABSTRACT FROM AUTHOR]

Abstract: Assessing the effects of air quality management strategies in urban areas is a major concern worldwide because of the large impacts on health caused by the exposure to air pollution. In this sense, this work analyses the changes in urban air quality due to the introduction of a maximum speed limit to 80 km h−1 on motorways in a large city by using a novel methodology combining traffic assimilation data and modelling systems implemented in a supercomputing facility. Albeit the methodology has been non-specifically developed and can be extrapolated to any large city or megacity, the case study of Barcelona is presented here. Hourly simulations take into account the entire year 2008 (when the 80 km h−1 limit has been introduced) vs. the traffic conditions for the year 2007. The data has been assimilated in an emission model, which considers hourly variable speeds and hourly traffic intensity in the affected area, taken from long-term measurement campaigns for the aforementioned years; it also permits to take into account the traffic congestion effect. Overall, the emissions are reduced up to 4%; however the local effects of this reduction achieve an important impact for the adjacent area to the roadways, reaching 11%. In this sense, the speed limitation effects assessed represent enhancements in air quality levels (5–7%) of primary pollutants over the area, directly improving the welfare of 1.35 million inhabitants (over 41% of the population of the Metropolitan Area) and affecting 3.29 million dwellers who are potentially benefited from this strategy for air quality management (reducing 0.6% the mortality rates in the area). [Copyright &y& Elsevier]

This paper proposes a methodology based on non-parametric statistical techniques to analyse whether the ordinal preferences in the port selection process are stable, and also the intensity of those preferences. We apply this methodology to the Spanish case from the landside perspective in order to answer the following question: Has the increase in inter-port competition changed the port preferences? The result obtained is that the port selection pattern of the provinces has changed slightly, leading us to the conclusion that the relative appeal of the ports remains quite stable from the spatial perspective, despite the reform of the port system. [ABSTRACT FROM AUTHOR]

This paper quantifies the influence badly parked vehicles and on-street parking maneuvers have on average link journey times as a function of the duration of the events and the number of designated maneuvers and flow, by applying an M/M/∞ queueing model in which arrival and departure are all Poisson processes. The method has been validated using microsimulations calibrated by in-situ measurements taken in the streets of the city of Santander (Cantabria, Spain). The analysis on the delays shows a good fit for the M/M/∞ model for flows of 60–70% of capacity where the error is always lower than 5%. This demonstrates the efficiency of the M/M/∞ model for studying how on-street parking maneuvers and badly parked vehicles influence traffic flow and avoids the need to use generally more laborious microsimulation models. Microsimulations are used to calculate the reduction in link capacity for each case in the study and the increases in average journey times for the rest of the road users. This shows the effect that allowing on-street parking on arterial or main roads has on the rest of the traffic. [ABSTRACT FROM AUTHOR]

Objective. To assess fitness to drive among drivers with treated obstructive sleep apnea syndrome. Methods. A total of 5234 drivers who attended two Spanish Medical Driver Test Centers for assessment of their fitness to drive prior to renewing or issuing their driving license were included in the study. Information regarding sociodemographic aspects, patterns of driving, medical condition, medication use, and patterns of alcohol consumption was recorded. Results. Eleven out of 5234 drivers (0.2%) suffered from obstructive sleep apnea syndrome, all of them being treated with continuous positive airway pressure, and they were found fit to drive with restrictions. Conclusions. A lower than expected prevalence of patients with obstructive sleep apnea syndrome was found among drivers undergoing fitness to drive assessment. Suffering from obstructive sleep apnea syndrome does not prevent driving as long as the patient is undergoing adequately controlled treatment. [ABSTRACT FROM AUTHOR]

Normally public works carried out on ports have a huge impact on the surrounding area due to the transportation of large quantities of raw material. The impact is even greater if the works are carried out in an urban area resulting in serious traffic congestion as well as pollution, dust and noise. This paper proposes a model for the management of such works and is applied to a case study based on the new port at Laredo (Spain). The model optimises the distribution of loads between lorries and barges with the aim of minimising the total economic, social and environmental costs. The total cost of the system was calculated from the costs used in operating the lorries and barges as well as from a social cost represented by the costs to private transport users caused by the increased congestion due to the activity of lorries on the road network. All of this is limited by environmental restrictions aimed at keeping the emissions of both private and works vehicles within the established pollution and noise standards. Finally, a series of interesting conclusions are presented for the correct planning of the transport system that was analysed. [ABSTRACT FROM AUTHOR]

Background: The aim of the present study is to describe the inter-province variability of Road Traffic Injury (RTI) mortality on Spanish roads, adjusted for vehicle-kilometres travelled, and to assess the possible role played by the following explicative variables: sociodemographic, structural, climatic and risk conducts. Methods: An ecological study design was employed. The mean annual rate of RTI deaths was calculated for the period 2002-2004, adjusted for vehicle-kilometres travelled, in the 50 provinces of Spain. The RTI death rate was related with the independent variables described above, using simple and multiple linear regression analysis with backward step-wise elimination. The level of statistical significance was taken as p < 0.05. Results: In the period 2002-2004 there were 12,756 RTI deaths in Spain (an average of 4,242 per year, SD = 356.6). The mean number of deaths due to RTI per 100 million vehicle-kilometres (mvk) travelled was 1.76 (SD = 0.51), with a minimum value of 0.66 (in Santa Cruz de Tenerife) and a maximum of 3.31 (in the province of Lugo). All other variables being equal, a higher proportion of kilometres available on high capacity roads, and a higher cultural and education level were associated with lower death rates due to RTI, while the opposite was true for the rate of alcohol consumers and the road traffic volume of heavy vehicles. The variables included in the model accounted for 55.4% of the variability in RTI mortality. Conclusion: Adjusting RTI mortality rates for the number of vehicle-kilometres travelled enables us to identify the high variability of this cause of death, and its relation with risk factors other than those inherent to human behaviour, such as the type of roads and the type of vehicles using them. [ABSTRACT FROM AUTHOR]

The article discusses an innovative system for traffic management that is under installation in the city of Valencia, Spain. This new traffic-management system is based on streaming video techniques over a high-speed Transmission Control Protocol/Internet Protocol corporate network. The video-streaming application is a multicomponent distributed application whose main task is managing the distribution of video streams from the video servers to the service processes that execute at the final application servers in the traffic management center (TMC). A tree connecting the three Gigabit Ethernet switches and the L3 switch at the TMC was the core network topology. Since it uses multicast communication, the Video Stream Management Server allows the introduction of several applications and services.

Focuses on an automatic system for control of the air pollution in the industrialized area of Huelva, Spain. Geographical description and the environmental monitoring network of the area; Estimation of pollutant emissions due to road traffic; Overview of atmospheric and dispersion modelling.

• Various statistical learning techniques are compared in country and global models. • The TROPOMI instrument measurements are evaluated in the models. • The daytime and nighttime NO 2 are modelled separately for exposure assessment. • The ensemble tree-based methods are promising for global mapping. • The spatial prediction patterns need to be considered in the validation process. In countries where air pollution stations are unavailable or scarce, station measurements from other countries and atmospheric remote sensing could jointly provide information to estimate ambient air quality at a sufficiently fine resolution to study the relationship between air pollution exposure and health. Predicting NO 2 concentration globally with sufficient spatial and temporal resolution and accuracy for health studies is, however, not a trivial task. Challenges are data deficiency, in terms of NO 2 measurements and NO 2 predictors, and the development of a statistical model that can typify the regional and continental differences, such as traffic regulations, energy sources, and local weather. We investigated the feasibility of mapping daytime and nighttime NO 2 globally at a high spatial resolution (25 m), by including TROPOMI (TROPOspheric Monitoring Instrument) data and comparing various statistical learning techniques. We separated daytime (7:00 am - 9:59 pm) and nighttime (10:00 pm - 6:59 am) based on the local times. To study if one should build models for each country separately, national models in 4 selected countries (the US, China, Germany, Spain) were developed. We build the models for 2017 and used 3636 stations. Seven statistical learning techniques were applied and the impact of the predictors, model fitting, and predicting accuracy was compared between different techniques, national models, national and global models, and models with and without including the NO 2 vertical column density retrieved from TROPOMI. The ensemble tree-based methods obtained higher accuracy compared to the linear regression-based methods in national and global models. The global tree-based methods obtained similar accuracy to national models. Different spatial prediction patterns are observed even when the prediction accuracy is very similar. Separating between day and night can be important for more accurate air pollution exposure assessment. The TROPOMI variable is ranked as one of the most important variables in the statistical learning techniques but adding it to global models that contain other precedent remote sensing products does not improve the prediction accuracy. [ABSTRACT FROM AUTHOR]