1,721,488 research outputs found
Assessing efficiency drivers in municipal solid waste collection services through a non-parametric method
No full textMunicipal solid waste collection is a public service with impact on the environment, public health, and the appearance of a municipal area. The standard of efficiency achieved in providing this service has a direct impact on household expenditure, since the costs of collection are recovered through citizens’ taxes. The failure to consider relevant performance drivers recently led some Italian waste utilities into bankruptcy and financial collapse. Following prior research to identify the environmental and operational variables affecting the efficiency and quality of waste collection services, this study applies a more suitable and robust non-parametric method based on conditional order-m efficiency to identify the performance drivers of the waste collection services in 40 municipalities in Verona province, Italy. The exogenous variables studied could be clustered as 1) customer features (size of population served, population density, tourist flows, and percentage of non-residential customers; 2) household features, measured by number of inhabitants per house; and 3) operational features, represented by tons of waste collected for each load, method adopted (curbside or street bin), and maturity achieved with a given method. The study demonstrates that all variables affect the cost efficiency of waste collection with different intensity and direction
Finite Element and Equivalent Frame modeling approaches for URM buildings: Implications of different assumptions in the seismic assessment
No full textThe work aims at discussing the influence of modeling assumptions on the seismic assessment of Unreinforced Masonry (URM) structures when the Finite Element (FE) and Equivalent Frame (EF) modeling approaches are adopted. This influence was evaluated with reference to a benchmark URM wall by performing pushover analysis. The geometry of this wall, with two stories and four vertical rows of windows, is representative of a facade of an existing building that was heavily damaged after the 2016-2017 Central Italy earthquakes. Typical issues faced by practitioners in the modeling process are widely discussed, contributing to the harmonization in the use of FE and EF based approaches (i.e., reduction of scatter in predictions). Several numerical models were assessed as a result of the consideration of different modeling assumptions, either individually or in combination. Pushover seismic analyses of the reference wall were performed after validating the FE approach at the panel scale against benchmark shear tests of representative piers. Then, the capacity curves of the reference wall were compared between the FE and EF models as well as the predicted damage patterns against the actual damage. Large differences in terms of secant stiffness were observed, higher in EF models (83%), while there were smaller differences in the maximum base shear force (35% in FE models). All models predicted a similar displacement capacity, except in one case, for which the displacement was much larger. For this reason, there was a wide range of predictions of acceleration capacity for the Near Collapse limit state (2.35-7.22 m/s2). Regarding the damage patterns, the predictions showed a higher concentration of damage at the ground story when compared with the damaged existing wall. The failure mode of base piers is however consistent with the one observed after the 2016-2017 Central Italy earthquakes, i.e., diagonal cracking. Both FE and EF models were unable to predict the severe damage state at the 1st story due to considering a mass prThis work is financed by national funds through FCT-Foundation for Science and Technology, under grant agreement [2020.09178.BD] attributed to the first author. This work was partly financed by FCT/MCTES through national funds (PIDDAC) under the R & D Unit Institute for Sustainability and Innovation in Structural Engineering (ISISE) , under reference UIDB/04029/2020
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
Economic-financial analysis of the Italian packaging waste management system from a local authority's perspective
Full text linkVariations 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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