86,563 research outputs found
COMPARISON OF URBAN RETROFITTING SCENARIOS FOR SUSTAINABLE STORMWATER CONTROL: A CASE STUDY IN MILAN, ITALY
No full textThe traditional approach of stormwater management in urban areas frequently affected by floods has proven to be unsustainable for the growing urbanization scenario as well as not adapted to provide climate change resilience. In the spirit of water sensitive cities, a stormwater management change is necessary, moving from pipe-based conveyance system to solutions able to manage at its source by small scale structures sprawled over the entire watershed, in a collection of systems and practices known as SuDs (Sustainable Urban Drainage Systems). These techniques provide several benefits not only related to risk mitigation but also to water quality and ecosystem services enhancement that make cities resilient also in terms of climate change. Currently stormwater and land use regulations mostly define a flow-limit to reduce discharge on the sewer systems. In this way, however, the search for further benefits is not encouraged. Flow-limit restrictions are obtained through storage control systems designed with design-storm methods that neglects the effect of pre-filling reducing the storage capacity before a new rainfall event. This research compares different stormwater management solutions for a new developed area located in Bresso municipality, in the metropolitan area of Milan (Italy), within the Seveso River watershed. The proposed scenarios go from no intervention to completely avoiding discharge on the sewer network with the implementation of stormwater control structures (permeable pavements, green roofs, retention basins, among others). The storage facilities are designed with a traditional design method and then their performance is evaluated with rainfall-runoff and routing model continuous simulations, also used to compare the different scenarios. The simulations confirm that is possible to reach more restrictive goals beyond the flow-limit regulations using stormwater controls structures that also provide multiple benefits and have significant effects in terms of hydraulic risk mitigation at watershed level. Continuous simulation shows that the effect of chained rainfall events can however reduce controls performance and should be considered when designing
Sustainable Permeable Asphalt System on Road Infrastructures
No full textPermeable Asphalt Systems (PAS) ensure, as well as road safety, environmental benefits by promoting the infiltration and filtration of stormwater and thus restoring the hydrological cycle. This work focuses on the evaluation of the filtration efficiency of a sustainable permeable asphalt system actually implemented on the Adriatic Bridge (Bari, Italy). In order to reach this goal, firstly, several laboratory studies for in-deep analyzed every aspect of permeable asphalt and of materials involved in the filtration processes were carried out. Hence, the first part of this work is intended to present the results obtained from these preliminary study: dry roads particulate matter (PM) samples from Apulia roads were collected and granulometrically characterized by means of mathematical model; then the clogging process within the PM loaded-permeable pavement specimens and the hydraulic conductivity reduction connected to it were observed; afterwards the pore structure of permeable pavement specimens was re- constructed by means of x-ray tomography; thereon a numerical model for determining the hydraulic conductivity of a 3D reconstructed permeable pavement specimens was developed by means of the Computational Fluid Dynamics (CFD). The findings of these studies have made a critical contribution to the development of the practical part of this work. The second part of the work is devoted to analyzing and modeling the experimental sustainable permeable asphalt system of the bridge. The system, composed of an open-graded friction-course (OGFC) and an infiltration trench, was reproduced in laboratory. The filtration efficiency was evaluated both for the individual system components and for the whole integrated system simulating various rainfall conditions. Meanwhile, quality analyses of the inflow and outflow stormwater collected directly in-situ from the system were also performed. The integrated system showed both in laboratory and in-situ good filtration properties and a high power of depletion of PM materials. In conclusion, the system, with some shrewdness, can be implemented on road infrastructures as a diffuse treatment system. Further researches are aimed at developing a numerical model able of predicting the particulate separation processes within the PAS for investigating the applicability in any context as geographical and environmental conditions change
Functional feasibility in optimal evaluation of water distribution network performances
No full textThe traditional approach for the optimization of water distribution networks (WDNs) does
not always lead to consistent solutions from an operational point of view. The latest optimization
algorithms identify solutions that are “the best solutions” in mathematical terms but that can be
less than robust against changes in operating conditions, resulting in the worst case in hydraulically
infeasible configurations. Thus, this paper aims to provide a methodology that can synthesize the
network performance capabilities under the change in operating conditions with two convergent
strategies. The first consists of the implementation of new performance indices (PIs), the demand
deficit and the pressure range, and the evaluation of their ability to criticality highlight in operating
conditions. The second is the introduction of a new approach to weight the infeasible solutions in the
final result, which are those inconsistent with the real hydraulic network performances. The analysis
shows that the use of these new indices makes it easier to understand the behavior of the network
and to identify any weaknesses. This is true if these indices consider the hydraulically inconsistent
solutions that may arise from the simulations of different operation conditions; otherwise, results that
poorly represent the real behavior of the network would be obtained
Negli ambiti fluviali: limitazione del rischio idraulico e riequilibrio ambientale e insediativo
No full textIl contributo affronta il tema della gestione integrata delle acque negli ambiti fluviali, proponendosi di superare da un lato il settorialismo di molti interventi recenti, e dall’altro i limiti di strumenti quali i Contratti di fiume, che pur abbracciando una scala intercomunale e promuovendo una visione intersettoriale, hanno inciso marginalmente sulle decisioni assunte.
Si propone di formulare dieci progetti-pilota per altrettanti ambiti di bacino italiani, selezionati in base alle criticità ambientali e territoriali emergenti, e qui promuovere interventi idraulici-territoriali integrati entro due principali ambiti d’azione. “A monte”, manutenzione programmata dei versanti e opere di ingegneria verde a basso impatto ambientale, entro un più generale sostegno delle aree interne montane a partire da un ripensamento della politica forestale. “A valle” la massimizzazione degli ambiti di esondazione naturali, la riorganizzazione dell’edificato e del suolo urbanizzato vicino ai corsi d’acqua e un più equilibrato prelievo nei periodi di secca
Expeditious pump rescheduling in multisource water distribution networks
No full textAbstractCost minimization is the main issue for water companies when establishing pumping regimes for water distribution. Remarkable reductions in operation costs can be achieved by optimizing the pump scheduling problem. In this paper a near optimum solution is proposed for internal multi-sources networks with a large amount of pumps per station. The proposed method is based on a local search algorithm which explores the neighborhood of an optimized solution obtained by the subdivision of the network into pumping station influence areas.A real case of study is presented and discussed, results are also compared to the solution obtained with a GA
Is maximal exercise improvement induced by ischemic preconditioning maneuvers (IPM) related to plasma concentration changes of oxidative stress markers?
No full textIschemic preconditioning of the muscle improves maximal exercise performance but not maximal oxygen uptake in humans
No full textVariations on the Author
No full text“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
[Newspaper Clipping: Author Claims Evidence of Second JFK Assassin #1]
No full textNewspaper article titled "Author Claims Evidence of Second JFK Assassin." The article states that author Richard J. Whalen concluded "that there is circumstantial evidence to support the theory of a second assassin in the shooting of President John F. Kennedy.
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