691 research outputs found

    Safety ranking definition for infrastructures with high PTW flow

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    Powered two-wheelers (PTWs) provide a suitable mode for a large portion of population in many cities due to rider's personal convenience and the vehicle supposed easiness of manoeuvring. At the same time PTWs present serious safety issues compared to other motorized vehicles. This paper reports the main outcome of study carried out in Rome, where this mode is very popular and assesses the economic efforts to make infrastructure safer for PTWs. The methodology, extensively described in the paper, includes three steps: the accident analysis, the development of economic indicators of accidents costs, the maintenance priority. In the first step the location of the PTWs local accidents are identified, then the accidents are analyzed by means of the suitable indicators and, among these the safety potential (SAPO). Lastly, according to the results of the analyzed indicators the need of infrastructure maintenance will be defined. Usually SAPO is applied to rural areas, but here it has been adapted to describe the phenomena of the urban area in hand. As a result, the estimation of the saving potential to improve the infrastructure safety levels, thus reducing the amount of accidents, is presented, along with recommendations on how to upscale the SAPO at city level

    Green public procurement criteria for road infrastructures: State of the art and proposal of a weighted sum multicriteria analysis to assessenvironmental impacts

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    In the last years, the attention to environmental issue is growing, demonstrating the interest to protect the nature and to better use the non-renewable resources. At international level, and especially in the European Community, for different trades, a wide production of voluntary documents and institutional acts proves the interest and the need for a green economy. An innovative approach may lead to the experience of Green Public Procurements (GPP), to protect the environment as a public interest and to promote technological developments. So far, the experiences of GPP are limited, not entirely positive and in the field of road infrastructures almost entirely absent. Construction and maintenance of road infrastructures is objectively more complex than purchasing goods or services. The paper proposes the integration of the weighted sum multi-criteria analysis into existing procedures. The methodology needs for environmental labels related to materials, machines and works which contribute to the final product "road". The labels are recognized at international level and consistent with procedures, conditions and criteria currently published in road tenders, therefore the approach can be followed to pursue the environmental sustainability of road infrastructures without compromising the economic attention

    Headway in large-eddy-simulation within the SPH models

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    In the present paper we show some preliminary resuslts of a novel LES-SPH scheme that extends andgeneralizes the approach described in [2]. Differently from that work, the proposed scheme is based on the definition of a Quasi-Langragian Large-Eddy-Simulation model where a small velocity deviation is added to the actual fluid velocity. When the LES equations are rearranged in the SPH framework, the velocity deviation is modelled through the Particle Shifting Technique (PST), similary to the δplus-SPH scheme derived in [3]. The use of the PST allows for regular particle distributions, reducing the numerical errors in the evaluation of the spatial differential operators. As a preliminary study of the proposed model, we consider the evolution of freely decaying turbulence in 2D. In a particular we show that the present scheme predicts the correct tendencies for the direct and inverse energy cascades

    ROADS—Rover for Bituminous Pavement Distress Survey: An Unmanned Ground Vehicle (UGV) Prototype for Pavement Distress Evaluation

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    Maintenance has a major impact on the financial plan of road managers. To ameliorate road conditions and reduce safety constraints, distress evaluation methods should be efficient and should avoid being time consuming. That is why road cadastral catalogs should be updated periodically, and interventions should be provided for specific management plans. This paper focuses on the setting of an Unmanned Ground Vehicle (UGV) for road pavement distress monitoring, and the Rover for bituminOus pAvement Distress Survey (ROADS) prototype is presented in this paper. ROADS has a multisensory platform fixed on it that is able to collect different parameters. Navigation and environment sensors support a two-image acquisition system which is composed of a high-resolution digital camera and a multispectral imaging sensor. The Pavement Condition Index (PCI) and the Image Distress Quantity (IDQ) are, respectively, calculated by field activities and image computation. The model used to calculate the I-ROADS index from PCI had an accuracy of 74.2%. Such results show that the retrieval of PCI from image-based approach is achievable and values can be categorized as "Good"/"Preventive Maintenance", "Fair"/"Rehabilitation", "Poor"/"Reconstruction", which are ranges of the custom PCI ranting scale and represents a typical repair strategy

    Cold asphalt contaning 100% reclamed asphalt. A sustainable technology for cycle paths and maintenance intervations

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    Both the National Recovery and Resilience Plan (Next Generation EU Program) and the development strategies for Smart Cities focus on cycle and pedestrian paths. Their pavements must be safe, durable and sustainable and considering the need to preserve the resources that Planet Earth offers to humans, it is essential to opt for innovative construction technologies that allow recycling methods without necessarily involving the addition of first-use materials. In the field of road infrastructure, the recovery of material deriving from the demolition of old pavements (RA - Reclaimed Asphalt) is only possible thanks to the use of specific products. A state-of-the-art rejuvenator is currently being used for the construction of cycling paths with 100% cold-mixed RA. This product is currently being studied for the INFRAROB project: “Maintaining integrity, performance and safety of the road infrastructure through autonomous robotized solutions and modularization” (Horizon 2020) with particular reference to “potholes patching” materials. Some technical data of the experiences developed to date are shown below

    Materials study to implement a 3D printer system to repair road pavement potholes

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    InfraRob is a research project funded by the European Commission's research programme Horizon 2020 that aims to maintain integrity, performance, and safety of the road infrastructure through autonomous robotized solutions and modularization. A specific task of the project is focused on the development of a system 3D printer able to extrude a specific mixture for filling in small cracks and potholes, to be integrated with an existing small autonomous carrier. The first step of the research deals with the definition of the optimal parameters of the system 3D printer/mixture, by studying in parallel the material design and the printer design. This paper presents the study performed on a mixture chosen among those commonly used for road potholes repair. The mixture is studied to achieve and balance the different conflicting performances: consistence, flowability homogeneity, and internal structure. In addition to the basic components, the use of special additives has also been explored to improve the plasticity and adhesivity of the mixture. The first phase of tests is conducted to define the main printing controls: i) Extrudability control: materials for 3D printing need to have an acceptable degree of extrudability, which is related to the capacity of a material to pass continuously through the printing head; ii) Flowability control, to ensure the mixture can be easy-pumpable in the delivery system and easy-usable on the crack or the pothole to be filed-in; iii) Setting time control: printing material requires a certain setting time to maintain a consistent flow rate for good extrudability, thus appropriate additives are needed to control the setting time. The second phase includes in situ tests to verify the compaction of the mixture under the traffic loads. The paper presents the results of the lab and in situ tests, and the features of the chosen mix, suitable to be managed by the 3D printer

    How to choose a good marker to analyze the olive germplasm (Olea europaea l.) and derived products

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    The olive tree (Olea europaea L.) is one of the most cultivated crops in the Mediterranean basin. Its economic importance is mainly due to the intense production of table olives and oil. Cultivated varieties are characterized by high morphological and genetic variability and present a large number of synonyms and homonyms. This necessitates the introduction of a rapid and accurate system for varietal identification. In the past, the recognition of olive cultivars was based solely on analysis of the morphological traits, however, these are highly influenced by environmental conditions. Therefore, over the years, several methods based on DNA analysis were developed, allowing a more accurate and reliable varietal identification. This review aims to investigate the evolving history of olive tree characterization approaches, starting from the earlier morphological methods to the latest technologies based on molecular markers, focusing on the main applications of each approach. Furthermore, we discuss the impact of the advent of next generation sequencing and the recent sequencing of the olive genome on the strategies used for the development of new molecular markers

    Conflict of interest regulation in European parliaments: Studying the evolution of complex regulatory regimes

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    This is the author accepted manuscript. The final version is available from Wiley via the DOI in this record.The growing complexity of parliamentary ethics regulation adopted over the last decades makes the systematic examination of its nature and the rationales underpinning regulatory choices an important endeavor. In this paper we introduce conceptualizations and measurements of conflict of interest (COI) regulation directed toward assuring the impartial and unbiased decisionmaking of national parliamentarians. We distinguish the strictness of rules, the nature of enforcement, sanctions, and transparency requirements as core elements defining COI regimes. Applying our framework to 27 European democracies, we select two cases for in-depth analysis in which legislators chose very different solutions in response to growing pressures to regulate themselves, to inductively explore the drivers underpinning the choice of COI mechanisms: the United Kingdom, which adopted a highly transparency-oriented regime, and Belgium, which adopted a highly sanction-oriented COI regime. Echoing neo-institutionalist perspectives, the longitudinal analyses indicate how the two democracies’ different institutional environments shape distinct answers to similar functional pressures.European Research CouncilCollege of Social Sciences and International Studies, University of Exete

    Effects of Surotomycin on Clostridium difficile Viability and Toxin Production In Vitro

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    The increasing incidence and severity of infection by Clostridium difficile have stimulated attempts to develop new antimicrobial therapies. We report here the relative abilities of two antibiotics (metronidazole and vancomycin) in current use for treating C. difficile infection and of a third antimicrobial, surotomycin, to kill C. difficile cells at various stages of development and to inhibit the production of the toxin proteins that are the major virulence factors. The results indicate that none of the drugs affects the viability of spores at 8Ă— MIC or 80Ă— MIC and that all of the drugs kill exponential-phase cells when provided at 8Ă— MIC. In contrast, none of the drugs killed stationary-phase cells or inhibited toxin production when provided at 8Ă— MIC and neither vancomycin nor metronidazole killed stationary-phase cells when provided at 80Ă— MIC. Surotomycin, on the other hand, did kill stationary-phase cells when provided at 80Ă— MIC but did so without inducing lysis
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