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Nanaki E.A.,University of Western Macedonia | Koroneos C.J.,University of Western Macedonia | Roset J.,Polytechnic University of Catalonia | Susca T.,BAM Federal Institute of Materials Research and Testing | And 6 more authors.
Sustainable Cities and Society | Year: 2017

The transportation sector is one of the largest sources of EU's greenhouse gas emissions. In 2011, transportation represented approximately 25 percent of total EU's greenhouse gas emissions. Urban mobility accounts for 40% of all CO2 emissions of road transport and up to 70% of other pollutants from transport. As, transportation and mobility play a crucial part both in urban economics and the quality of life, it is of great significance to ensure a low carbon transportation sector, so as to deal with the threat that climate change poses to urban areas. This study examines the factors that affect the production of carbon dioxide (CO2) as well as of air pollutants, in 9 major European cities, aiming to provide a comprehensive overview of the actual knowledge on the atmospheric pollution from public transportation systems. CO2 emissions as well as air pollutants, such as CO, HC, PM, NOx are calculated for the diesel and CNG bus fleets of the European cities under study. Finally the environmental benefits, in terms of CO2 and CO, HC, PM, NOx emissions reductions, from the penetration of different biodiesel blends (from B10 to B100) to the bus fleets are estimated. © 2016 Elsevier Ltd

Karadimou E.,York EMC Services | Armstrong R.,York EMC Services | Adin I.,Centro de estudios e investigaciones técnicas de Gipuzkoa | Deniau V.,IFSTTAR | And 4 more authors.
IEEE International Symposium on Electromagnetic Compatibility | Year: 2015

The research presented here deals with the electromagnetic compatibility in the railway environment. In particular it focuses on four research areas: the spot signalling systems, the track circuits, the GSM-R and the broadcasting services. A review of the current railway standards is followed by a research on the immunity limits, the worst case scenarios and cross acceptance EMC tests for the four areas. © 2015 IEEE.

Carvalho L.,European Commission - Joint Research Center Ispra | Carvalho L.,UK Center for Ecology and Hydrology | Mcdonald C.,UK Center for Ecology and Hydrology | de Hoyos C.,CEDEX | And 8 more authors.
Journal of Applied Ecology | Year: 2013

Summary: A safe, clean water supply is critical for sustaining many important ecosystem services provided by freshwaters. The development of cyanobacterial blooms in lakes and reservoirs has a major impact on the provision of these services, particularly limiting their use for recreation and water supply for drinking and spray irrigation. Nutrient enrichment is thought to be the most important pressure responsible for the widespread increase in cyanobacterial blooms in recent decades. Quantifying how nutrients limit cyanobacterial abundance in lakes is, therefore, a key need for setting robust targets for the management of freshwaters. Using a data set from over 800 European lakes, we highlight the use of quantile regression modelling for understanding the maximum potential capacity of cyanobacteria in relation to total phosphorus (TP) and the use of a range of quantile responses, alongside World Health Organisation (WHO) health alert thresholds for recreational waters, for setting robust phosphorus targets for lake management in relation to water use. The analysis shows that cyanobacteria exhibit a nonlinear response to phosphorus with the sharpest increase in cyanobacterial abundance occurring in the TP range from about 20 μg L-1 up to about 100 μg L-1. The likelihood of exceeding the World Health Organisation (WHO) 'low health alert' threshold increases from about 5% exceedance at 16 μg L-1 to 40% exceedance at 54 μg L-1. About 50% of the studied lakes remain below this WHO health alert threshold, irrespective of high summer TP concentrations, highlighting the importance of other factors affecting cyanobacteria population growth and loss processes, such as high flushing rate. Synthesis and applications. Developing a more quantitative understanding of the effect of nutrients on cyanobacterial abundance in freshwater lakes provides important knowledge for restoring and sustaining a safe, clean water supply for multiple uses. Our models can be used to set nutrient targets to sustain recreational services and provide different levels of precaution that can be chosen dependent on the importance of the service provision. Developing a more quantitative understanding of the effect of nutrients on cyanobacterial abundance in freshwater lakes provides important knowledge for restoring and sustaining a safe, clean water supply for multiple uses. Our models can be used to set nutrient targets to sustain recreational services and provide different levels of precaution that can be chosen dependent on the importance of the service provision. © 2013 British Ecological Society.

Fernandez Serrano R.,CEDEX | Fernandez Serrano R.,University Polite Cnica Of Madrid | Fernandez Serrano R.,New York University | Iskander M.,New York University | Tabe K.,Sharda University
Geotechnique Letters | Year: 2011

A physical model based on transparent soil technology is presented as a novel laboratory tool for ground contamination research. The model aims to reproduce both unsaturated and saturated conditions within a Spanish soil formation known as Miga sand. A soil surrogate made of a waterabsorbing polymeric gel was employed. Multi-phase flow froma leaking underground storage tank was simulated in both saturated and unsaturated conditions in order to illustrate the usefulness of the technique in simulating a hypothetical spill of a light non-aqueous phase liquid under well-controlled test conditions. The plume observed was found to be spatially variable. The technique permits, for the first time, the simulation of specific grain size distributions in a transparent soil surrogate and visualization of plume development in three dimensions. Preliminary results indicate that the model is a potentially powerful tool for visualising pollutant transport in porous media. A brief description of the test setup, and a summary of the advantages, limitations, and prospective applications are presented.

Alaejos P.,Laboratory Central Of Estructuras Y Materiales | De Juan M.S.,CEDEX | Rueda J.,CEDEX | Drummond R.,Kleemann gmbh | Valero I.,Gestora de Runes
RILEM State-of-the-Art Reports | Year: 2013

Recycled aggregates differ from the natural ones in several properties, making their quality lower in general, but suitable enough to be used in different applications inside the construction field in many cases. On the other hand, recycled aggregates are quite more heterogeneous compared to natural ones, varying their characteristics along the production process. Therefore, quality assurance is extremely important in order to provide users enough confidence in the material, having properties satisfying requirements, and also with defined tolerances on variation throughout a delivery. Main factors affecting the quality of recycled aggregates are described in this chapter: influence of the production process, types of treatments, Impurities content, quality of the original debris. The composition and the nature of its components as well as the presence of impurities are the principal parameters affecting the final quality of the recycled aggregates. However, some specific methods and operations may be taken into account during the production process in order to obtain suitable recycled aggregate for use in higher-value applications. The control of the incoming deliveries to the recycling plant is also a basic measure to avoid an excessive heterogeneity in recycled aggregates. In several countries, the standards have been amended in order to cover specific aspects of recycled aggregates, and even some certification systems have been also developed. Different international standards on quality assurance of recycled aggregates are reviewed in this chapter. © RILEM 2013.

Alaejos P.,CEDEX | Alaejos P.,Polytechnic University of Mozambique | Lanza V.,CEDEX
Cement and Concrete Research | Year: 2012

In this research, the effect on the reactivity of aggregates containing different quartz crystal sizes (0-10 μm; 10-60 μm, 60-130 μm) has been studied, proposing a unique limit for all of them applied to their weighted sum (Equivalent Reactive Quartz). For this aim, the expansion in mortar bars has been correlated with the content of reactive components, and values of the individual mathematic weights for different crystal sizes have been obtained: 8.3 vol.% of quartz 10-60 μm; and 2.6 vol.% of quartz < 10 μm (corresponding to 0.1% expansion at 14 days). The results show that 60-130 μm crystal size of quartz has a negligible effect on the expansion. These individual limits can be reduced to a unique one equal to 2.6 vol.% applied to the Equivalent Reactive Quartz. The use of this concept allows to evaluate the reactivity of aggregates in which there are simultaneously different reactive quartz crystal sizes. © 2011 Elsevier Ltd. All rights reserved.

Alaejos P.,CEDEX | Alaejos P.,Polytechnic University of Mozambique | Lanza V.,CEDEX | Bermudez M.A.,Ministry of Public Works | Velasco A.,CEDEX
Cement and Concrete Research | Year: 2014

The accelerated mortar bar test (AMBT) is one of the most common tests to detect reactive aggregates although it has some limitations: there is no agreement on the limit of expansion, fails appear when testing slowly reactive aggregates and a laborious work is needed to find the pessimum content. An experimental programme on the AMBT has been carried out to overcome these limitations. Rapid and slowly reactive aggregates extracted from real Spanish structures affected by alkali silica reaction have been used. As a result, the test detected correctly all the reactive aggregates, but with the following requirements: a limit of 0.10% at 14 days for rapid reactive aggregates and 0.20% at 90 days for slowly reactive aggregates. Also the pessimum content has been found between 5 and 15 vol% of equivalent reactive quartz, giving a peak expansion of 0.42% (14 days). The expansion after this peak decreased but it was always over 0.10%. © 2014 Published by Elsevier Ltd.

Bermudez M.A.,CEDEX | Alaejos P.,Polytechnic University of Mozambique
ACI Materials Journal | Year: 2010

In a marine environment, reinforcement corrosion due to chloride attack is the most important degradation process of reinforced concrete. Diffusion models found in the bibliography show opposite results, over or underestimating chloride diffusion coefficient values for tidal zone concretes. In this paper, the chloride penetration rate for tidal zone concretes has been modeled from data collected from a high number of references, covering a wide range of concrete qualities and not considering accelerated test results. Also, this model has been checked with experimental results obtained from five Spanish maritime structures. The basic parameters considered in this model were water-cement ratio (w/c), type, and content of mineral admixtures. Finally, the efficiency factors of fly ash and silica fume (their contribution to chloride permeability) have been calculated. Copyright © 2010, American Concrete Institute. All rights reserved.

Lechuga A.,CEDEX
Natural Hazards and Earth System Sciences | Year: 2013

In past decades theoretical studies have been carried out with the double aim of improving knowledge of the main characteristics of the rogue wave and of attempting to predict its sudden appearance. We have tried to generate rogue waves in a water wave tank, using a symmetric spectrum (Akhmediev et al., 2011a) as input on the wave maker.

The next step has been to apply a theoretical model to the amplitude envelope of these waves. After some considerations we agreed the best model to be an analog of the Ginzburg-Landau equation. © 2013 Author(s).

RUEIL MALMAISON CEDEX, 02-Mar-2017 — /EuropaWire/ — The new South Europe Atlantic high-speed line (SEA HSL), which will put Bordeaux within 2 hours of Paris starting this July, was inaugurated on February 28th, 2017 by French President François Hollande, in the presence of VINCI Chairman and CEO Xavier Huillard, VINCI Concessions CEO Nicolas Notebaert, VINCI Railways Chairman Christophe Pélissié du Rausas, and LISEA CEO Laurent Cavrois. The new line was built and will be operated and maintained until 2061 under a concession contract between SCNF Réseau and LISEA, in which VINCI Concessions holds a 33.4% stake. The inauguration is a key milestone for VINCI Concessions: after managing this programme and delivering Europe’s largest rail works endeavour ahead of schedule, on budget and in keeping with the most stringent environmental requirements, the teams are preparing apply the same uncompromising standards to the line’s maintenance and operation. With this new phase, VINCI Concessions will become the first private sector player to manage operations on a high-speed line in France, via its 70% interest in MESEA, the company operating and maintaining the line. To succeed in this next phase, VINCI Concessions will be able to rely on the VINCI Group’s holistic model and its dual construction and concession approach, which for example involved factoring operation and maintenance requirements into the early design phase. The teams will also be able to count on VINCI Concessions’ cutting-edge experience operating world-class mobility infrastructure around the globe. And, as the SEA HSL was developed under a PPP, it blends beautifully into the Group’s vision: it tackles the considerable challenges in regional development by rallying public and private sector players and thereby harnessing unprecedented energy. The inauguration ceremony took place in Charente, in Villognon, a symbolically meaningful location for this new phase in the project: it was one of the two large bases during the construction phase and will henceforth be used as the main base for line maintenance.

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