938 research outputs found

    Greenery as a mitigation strategy to urban heat and air pollution: a comparative simulation-based study in a densely built environment.

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    The urban heat island and the urban air pollution concentration are two major climate-change-related phenomena affecting the built environment worldwide. This paper aims to verify the potential effect of different mitigation measures through a simulation study. In detail the present study focuses on the analysis of the environmental impacts of urban vegetation, such as green facades, vertical greenery, and green pavements. After an extensive screening of the literature review, an investigation of the impact of the most common built environment design variables in a defined case study led to the definition of a typical urban canyon was tested. The results show that the presence of trees in a street canyon could reduce the air temperature peaks by 5-10 Ā°C, while the high-level vegetation canopies can lead to a deterioration in air quality with a PM concentration increasing by 1.2-1.5%. Instead, using low-level green infrastructure improves the air quality conditions on the sidewalk, reducing the NOx in the range of 10-20%. The analyzed high-level greenery generated an air temperature reduction effect on a street level ranging from 8 to 12Ā°C. The present work contributes to clarifying the potential mitigation effect of green infrastructure in a densely built environment, where the risk of increasing temperatures and air pollutants is foreseen to be more intense in the coming years

    Determining behavioural-based risk to SLODs of urban public open spaces: Key performance indicators definition and application on established built environment typological scenarios

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    A behavioural-based approach can be used to assess how usersā€™ reactions to surrounding environmental conditions can alter the urban Built Environment (BE) risk to Slow Onset Disasters (SLODs). Public Open Spaces (POSs) in the BE are relevant scenarios, due to micro-climate-related stress, usersā€™ vulnerabilities (e.g., age, health frailty) and exposure time. Simulation methods can support behavioural-based risk-assessment, but results are generally site-specific. Performing analysis on BE Typologies (BETs) can improve robustness, since BETs represent archetypes from real-world scenarios. This work adopts a behavioural-based approach to evaluate time-dependant usersā€™ risks of POSs in different BETs due to SLODs-related stress (i.e., heat, air pollution). UTCI and AQI values are mapped within each BET. Usersā€™ distributions are then calculated depending on thermal acceptability correlations. Key Performance Indicators are developed associating usersā€™ distribution to SLODs effects on health (i.e., sweat rate, water loss; health affection rate probability). The approach is applied to Italian BETs, under one relevant climate, rating their heat and air pollution risks. Results suggest critical conditions for toddlers. In detail, about 2-hour high heat exposure could result in dehydration, while 1-hour exposure to low NO2 concentration could result in +1% mortality probability. This approach could potentially support decision-makers on BE risk-assessment

    Pedestrian Single and Multi-Risk Assessment to SLODs in Urban Built Environment: A Mesoscale Approach

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    Pedestrians are increasingly exposed to slow-onset disasters (SLODs), such as air pollution and increasing temperatures in urban built environments (BEs). Pedestrians also face risks that arise from the combination of the BE features, the effects of SLODs on the microclimate, their own characteristics (e.g., health and ability), and the way they move and behave in indoor and outdoor BE areas. Thus, the effectiveness of sustainable risk-mitigation solutions for the health of the exposed pedestrians should be defined by considering the overlapping of such factors in critical operational scenarios in which such emergency conditions can appear. This work provides an innovative method to define a BE-oriented pedestrian risk index through a dynamic meso-scale approach that considers the daily variation of risk conditions. The method is ensured by a quick-to-apply approach, which also takes advantage of open-source repositories and tools to collect and manage input data, without the need for time-consuming in situ surveys. The resulting risk conditions are represented through meso-scale maps, which highlight the risk differences between BEs by focusing on their open spaces as fundamental parts of the urban road network. The method is applied to a significant case study (in Milan, Italy). The results demonstrate the ability of the approach to identify key input scenarios for risk assessment and mapping. The proposed methodology can: (1) provide insights for simulation activities in critical BE conditions, thanks to the identification of critical daily conditions for each of the factors and for single and multiple risks and (2) support the development of design and regeneration strategies in SLOD-prone urban BEs, as well as the identification of priority areas in the urban B

    Information extraction from multimedia web documents: an open-source platform and testbed

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    The LivingKnowledge project aimed to enhance the current state of the art in search, retrieval and knowledge management on the web by advancing the use of sentiment and opinion analysis within multimedia applications. To achieve this aim, a diverse set of novel and complementary analysis techniques have been integrated into a single, but extensible software platform on which such applications can be built. The platform combines state-of-the-art techniques for extracting facts, opinions and sentiment from multimedia documents, and unlike earlier platforms, it exploits both visual and textual techniques to support multimedia information retrieval. Foreseeing the usefulness of this software in the wider community, the platform has been made generally available as an open-source project. This paper describes the platform design, gives an overview of the analysis algorithms integrated into the system and describes two applications that utilise the system for multimedia information retrieval

    Chasing Brane Inflation in String-Theory

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    We investigate the embedding of brane anti-brane inflation into a concrete type IIB string theory compactification with all moduli fixed. Specifically, we are considering a D3-brane, whose position represents the inflaton Ļ•\phi, in a warped conifold throat in the presence of supersymmetrically embedded D7-branes and an anti D3-brane localized at the tip of the warped conifold cone. After presenting the moduli stabilization analysis for a general D7-brane embedding, we concentrate on two explicit models, the Ouyang and the Kuperstein embeddings. We analyze whether the forces, induced by moduli stabilization and acting on the D3-brane, might cancel by fine-tuning such as to leave us with the original Coulomb attraction of the anti D3-brane as the driving force for inflation. For a large class of D7-brane embeddings we obtain a negative result. Cancelations are possible only for very small intervals of Ļ•\phi around an inflection point but not globally. For the most part of its motion the inflaton then feels a steep, non slow-roll potential. We study the inflationary dynamics induced by this potential.Comment: 34 pages, 4 figures. Final version published in JCA

    Clinical care pathway program versus open-access system: a study on appropriateness, quality, and efficiency in the delivery of colonoscopy in the colorectal cancer

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    Open-access colonoscopy (OAC), whereby the colonoscopy is performed without a prior office visit with a gastroenterologist, is affected by inappropriateness which leads to overprescription and reduced availability of the procedure in case of alarming symptoms. The clinical care pathway (CCP) is a healthcare management tool promoted by national health systems to organize work-up of various morbidities. Recently, we started a CCP dedicated to colorectal cancer (CRC), including a colonoscopy session for CRC diagnosis and prevention. We aimed to evaluate the appropriateness, the quality, and the efficiency in the delivery of colonoscopy with the open-access system and a CCP program in the CRC. Quality indicators for colonoscopy in subjects in the CCP were compared to referrals by general practitioners (OAC) or by non-gastroenterologist physicians (non-gastroenterologist physician colonoscopy, NGPC). Attendance rate to colonoscopy was greater in the CCP group and NGPC group than in the OAC group (99%, 99%, and 86%, respectively). Waiting time in the CCP group was shorter than in the OAC group (3.88 Ā± 2.27 vs. 32 Ā± 22.31 weeks, respectively). Appropriateness of colonoscopy prescription was better in the CCP group than in the OAC group (92 vs. 50%, respectively). OAC is affected by the lack of timeliness and low appropriateness of prescription. A CCP reduces the number of inappropriate colonoscopies, especially for post-polypectomy surveillance, and improves the delivery of colonoscopy in patients requiring a fast-track examination. The high rate of inappropriate OAC suggests that this modality of healthcare should be widely reviewed
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