1,720,965 research outputs found

    Multi-criteria and multiscale assessment of building envelope response-ability to rising heat waves

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    Global warming increases the probability of extreme events and heat waves, intensified by Urban Heat Island phenomenon, triggering severe impacts on both human health and economy. The paper aims at developing a new methodological approach for the assessment of building ability to face rising temperatures, also considering the effects on the surrounding urban areas. It focuses on resilient retrofitting strategies need for building envelope according to three macro-categories: reliability, adaptability and mitigation ability. A set of indicators is defined to achieve a Response Index to cope with heat waves. The method is tested on reference building and its neighborhood. The selected strategies are investigated through an integrated and multilevel analysis with EnergyPlus and ENVI_met, in three different cities with increasing summer temperature. The final comparative analysis is carried out through a multi-criteria analysis according to the identified indicators. The best responsive solutions result the green ones combined with high albedo, but the research highlights also some controversial aspects. The method can be a valid tool to support the decisional process about heat waves mitigation in the roadmap towards a more responsive built environment

    Thermal and seismic capacity improvements for masonry building heritage: A unified retrofitting system

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    Today, the attention in the retrofitting of building is quickly growing. In this field, the re-use of waste materials and the innovation in the retrofitting techniques are among the crucial topics. Generally, thermal capacity and seismic resistance are two aspects very felt by the building owners. Commonly, independent approaches are assessed in order to cover the energy and mechanical lacks of a building. In such a way, the intervention may result time‐ and cost‐consuming or, sometimes, poorly effective. The present paper aimed to propose and validate a new retrofitting system based on the partial use of waste materials, such as fly ash and expanded glass (acting as a matrix), and a fiber open grid reinforcement. The proposal is suitable for the plastering of building with the double scope of thermal insulation and seismic strengthening throughout a unique application. An experimental investigation was carried out considering small‐scaled masonry panels with double-side retrofitting. The studied parameters were thermal transmittance and shear strength. The results evidenced the effectiveness of the proposed technique, able to significantly improve the un-retrofitted masonry, from both the thermal and mechanical point of view

    A new Fabric Reinforced Geopolymer Mortar (FRGM) with mechanical and energy benefits

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    A large part of the European building Heritage is dated back over centuries. Consequently, its structural and thermal performances are often inadequate. Commonly, different interventions are proposed for solving these issues separately. However, reasonable drawbacks arise when the structural retrofitting requires a direct contact with the target-member while the insulation layer is potentially interposed in between. In this scenario, the present research proposes a novel and unique system able to guarantee both the energetic and the structural retrofitting. Inorganic Matrix Composites (IMCs) are a promising solution in this sense. Among them, the Fabric Reinforced Cementitous Matrix (FRCM) is one of the most used; or rather a composite made of a fabric (open grid or mesh) within an inorganic matrix (lime or cement based). Even if the inorganic matrix has a relevant thickness (if compared with the one of the fabric), its thermal resistance is insufficient. The novelty of this work consists in assessing a new geo-polymeric FRCM-system by combining fly-ash binder (reused material) and expanded glass aggregate (recycled material). Direct tensile tests, for measuring the tensile strength, ultimate strain and elastic modulus, were performed in addition to thermal conductivity tests. The results were compared with those of traditional FRCM (commercially available). The potentiality of the proposal for structural and energy retrofitting is discussed and examples of its possible application are also reported

    Mitigation and Adaptation Strategies for Different Urban Fabrics to Face Increasingly Hot Summer Days Due to Climate Change

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    As global warming and heat waves are becoming more frequent and severe, cities, with their different morphological districts, must be at the forefront of environmental challenges. Notably, many Mediterranean towns maintain the original medieval urban fabric and the regular one. The research focuses on the development of a methodology with the application of high-resolution 3D modelling software ENVI-met V5.1 to analyze the microclimatic effects of mitigation and adaptation strategies derived from the study of medieval and regular urban fabric. The aim is to address contemporary challenges such as heat waves and urban heat island (UHI) effects in modern cities. By studying outdoor energy behavior in a southern Italian city (Bari), the research proposes scenarios for urban settlements in the face of climate change. This approach provides recommendations for creating more climate-resilient urban environments both in the historic and modern city. The use of trees with large crowns and tall shrubs and the inclusion of fountain jets are strategies to achieve sky view factor and air temperatures in the modern city similar to those in the historical fabric. Increasing albedo values and the use of green roofs prove to be further strategies for improving outdoor climatic conditions

    Energy and seismic drawbacks of masonry: a unified retrofitting solution

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    All over the world, a large part of existing buildings is not adequate to satisfy the safety requirement and the thermal comfort criteria. For this reason, the interest in structural and energy retroftting systems has steadily grown in the last decades. In this scenario, an innovative thermal resistant geopolymer mortar has been developed and used for Inorganic Matrix Composite (IMC) systems aimed to a combined seismic and energy new retroftting technique. The geopolymer-based IMC is able to ensure competitive mechanical properties with respect to the traditional lime-based IMCs and, at the same time, a signifcant reduction in thermal conductivity. In this paper, an experimental program is reported considering small-scaled masonry panels with double-side IMC-retroftting and determining both the in-plane shear strength and the thermal resistance. The experimental shear tests are aimed to compare the mechanical performance of the geopolymer innovative systems with those of the traditional lime-based ones. Moreover, the thermal resistance gain of the innovative solutions was measured and compared with traditional systems. The results evidenced the efectiveness of the proposed technique that signifcantly improved the performances of masonry walls from both the thermal and the mechanical point of view

    Improving environmental comfort and energy saving in School Buildings: a case study with the students’ participation

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    The study seeks to develop a replicable procedure in relation to environmental parameters of objective and subjective comfort perception, both through the use of dedicated Information Technologies and diagnostic instrumental methods (thermal and lighting audit) and assessment data collected from users (students and teachers), actively participating in the quality judgment. The involvement of students is intended to increase their awareness towards sustainable building issues and the adoption of behaviours aimed at saving energy and improving comfort condition

    Going Beyond Counting First Authors in Author Co-citation Analysis

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    The present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed

    Variations on the Author

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    “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

    Appropriate Similarity Measures for Author Cocitation Analysis

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    We provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
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