186,371 research outputs found
Risk based characterization of a contaminated industrial site using multivariate and geostatistical tools
No full textHuman and ecological risk assessment requires the sources, distribution, mobility and environmental behaviour of contaminants
to be investigated on a site-speci®c basis. It often deals with data sets which are relatively small and a ected by sampling gaps. In
the case of a polycyclic aromatic hydrocarbon (PAH) contaminated industrial site, Kriging interpolation of spatial data and prin-
cipal component analysis (PCA) proved useful for extracting additional value from the data set. Kriging was adopted for assessing
the horizontal and vertical distribution and transport of PAHs in soil. PCA was applied to PAH concentration and relative abun-
dance in soil samples and interpreted on the basis of the PAH physico-chemical and bio-degradation properties. It revealed corre-
lation with the products of a neighbouring factory and the weathering of the lighter PAHs. The geo- and multivariate statistical
results were coupled with the previous hydrogeological characterisation of the site to develop a site-conceptual model for use in the exposure scenario modelling for risk assessment
Bayesian statistics-based procedure for sampling of contaminated sites
No full textA variable density sampling pattern based on Bayesian statistics is presented and compared to a uniform density statistical pattern and a judgmental approach in a real case study. The Bayesian statistics, supported by a software tool, supplied a soil sampling plan similar to the judgmental one, especially for the number of sampling points and their location. It allowed statistical goals to be set and expert judgment to be included in the sampling strategy in a transparent and systematic procedure. For these reasons, it appears quite suitable for inclusion into Quality Assurance Quality Control plans
Assessing the Impact of Changes in Mobility Behaviour to Evaluate Sustainable Transport Policies: Case of University Campuses of Politecnico di Milano
No full textStarted in 2011, the “Città Studi Campus Sostenibile” project (CSCS), promoted by Politecnico di Milano and Università degli Studi di Milano, is aimed at turning the common university district in a model for quality of life and environmental sustainability. One of the topics of this project relates with transport and sustainable mobility.
In this framework, during the last three years, the Sustainable Office of the University, in collaboration with the university mobility manager, carried out two surveys on mobility and commuting, among students, professors and administrative staff. In 2015 were surveyed about 12.000 people and about 14.000 in 2017, respectively 27% and 24% of the total population of each year.
Through the analysis of the data of the last survey, we firstly provide a description of the current mobility patterns of the university population, then we calculate CO2 emissions from mobility activities to access Politecnico campuses. In order to estimate CO2 emissions of every trip, we utilize local emission factors for each transport mode. Previous studies evidenced how this component accounts for more than 40% of the total emissions of Politecnico di Milano.
Lastly, in order to identify in which context policy packages, aimed at increasing the modal share of sustainable transport modes, are more effective and efficient in reducing CO2 emission, we analyse a set of scenarios involving both different territorial contexts inside Lombardy region and different campuses population
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Going Beyond Counting First Authors in Author Co-citation Analysis
No full textThe 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
Appropriate Similarity Measures for Author Cocitation Analysis
No full textWe 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
No full textWe 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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