1,720,959 research outputs found
Shallow geothermal potential and numerical modelling of the geo-exchange for a sustainable post-earthquake building reconstruction (Potenza River valley, Marche Region, Central Italy)
Full text linkThe southern part of the Marche Region (Italy) was hit in 2016 by dramatic seismic events that caused damages and fatalities. After these events, the national and local administrations started a development plan to improve the energy efficiency of the restored or reconstructed buildings. Shallow geothermal energy, consisting of closed-loop Borehole Heat Exchangers (BHEs) coupled with heat pumps, could represent a first-order renewable choice for indoor air conditioning (heating and cooling) systems. The feasibility and potential of the BHEs also match this technology's null visual outdoor impact which is paramount in preserving the landscape of the earthquake-affected areas. However, the exploitation, sustainability, and correct design of these systems require detailed knowledge of the ground's geological, hydrogeological, and thermophysical properties. In this framework, the present study was carried out to map and test, through the G.POT algorithm, the shallow geothermal potential and sustainability of the Potenza River valley through the publicly available data from the Italian Seismic Microzonation studies — an extensive database of geognostic drillings and other geological and geophysical surveys. This step allowed us to assign the main thermal parameters (thermal conductivity, volumetric heat capacity, specific heat extracted) to each geological layer and averaged them over the first 100 m (i.e., a typical depth for BHEs). All the data were then interpolated to produce geothermal thematic maps to visualize and compare the potential and adequacy of the territory for the installation of closed-loop BHEs. Finally, finite elements numerical models (FEFLOW software) were developed in a balanced mode through the annual heating and cooling cycles to verify the sustainability of this renewable concerning the thermal impact induced to the ground by the BHEs during a long-term (20 years) operation
Evaluation of ground source heat exchangers system feasibility to contribute at the ecological transition of the Marche Region in the 2016 earthquakes reconstruction areas: numerical models and maps of the shallow geothermal energy potential
No full textIn 2016 central Italy was hit by a seismic sequence (Mmax 6.5) that caused human victims, damages, and collapses of buildings, changing hopelessly the urban landscape of many towns. After these events, the Marche Region started an economic program which involved measures for the restoration and reconstruction of damaged or destroyed buildings. In this context, the exploitation of shallow geothermal energy (SGE), through the installation of ground source heat exchangers (GSHEs) coupled with heat pumps, could be a useful tool for heating and cooling these new, or renovated, buildings, being SGE a renewable, clean and without surface impact technology solution for high efficiency space heating and cooling needs covering. This would strongly contribute to preserve the Central Apennine environment. To identify the most suitable areas for ground source heat exchangers, a map of the geothermal potential of the southern sectors of the Marche Region (upper-middle portion of the Potenza River) was developed. By consulting the third level seismic microzonation data made available by the National Civil Protection database, it was possible to reconstruct the stratigraphy of the area. In order to estimate the geothermal potential of the study area, the main parameters (thermal conductivity, volumetric heat capacity) were averaged over the first 100 meters of the subsoil, which is the most common depth of GSHEs. After this, all the investigated points were interpolated by means of dedicated algorithms to give a visualization of the spatial distribution of the geothermal potential throughout the study area. Further study has also involved numerical modelling approach in order to verify the thermal impact induced in the subsoil, during the time, by the system operation and detect the best solution to improve the sustainability of the geothermal solution. Indeed it was possible to reproduce, in detail, the undisturbed thermal assessment of the ground and the induced effects over time by the geothermal system operation. Starting from the 3D numerical modelling of closed loop heat exchangers field, by using the local geological and hydrogeological available features and, possibly, data produced by Ground Response Tests performed in the surrounding area, a calibration session of the modelling process was made. Several scenarios have been performed by means of the modelling analyses in order to simulate the thermal effects of GSHP running into the subsoil and detect the best countermeasures finalized to balance the heat seasonal exchange processes with the ground. A map representing the feasibility and potential of the GSHP solutions adoption is also achieved. Various graphs and images, describing the efficiency of the system and the thermal plume development in the subsoil, have been obtained
Going Beyond Counting First Authors in Author Co-citation Analysis
Full text linkThe 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
Full text link“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
Full text linkWe 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
Dispelling the Myths Behind First-author Citation Counts
Full text linkWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
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