4,816 research outputs found
Consistent derivation of the constitutive algorithm for plane stress isotropic plasticity. Part II: Computational issues
No full textThe implementation of the projected algorithm and of the consistent tangent tensor for general isotropic three-invariant elastoplastic models under plane stress conditions discussed in Part I of this paper [Valoroso, N., Rosati, L., 2008. Consistent derivation of the constitutive algorithm for plane stress isotropic plasticity. Part I: Theoretical formulation. International Journal of Solids and Structures, doi: 10.1016/j.ijsolstr.2008.08.012.] is addressed. The connections between the general three-dimensional case and the plane stress problem are analyzed in detail and an algorithmic treatment taking full advantage of the isotropic properties of the model is presented. In particular, intrinsic (matrix-free) expressions are provided for all steps of the stress computation scheme that allow one to carry out the numerical implementation in a way that is completely independent from the matrix representations. The numerical performances of the present solution scheme are evaluated through representative numerical examples
Transformation systems for incidence structures
No full textBy taking into account the transformation technique of Quattrocchi and Rosati, we study how to generate transformation systems for an incidence structure by starting from some given generating blocks and by a suitable permutation of the points. Furthermore, the method is applied to obtain the finite Andre planes by means of a minimal set of generating lines of Desarguesian planes
Analytical and differential reformulations of the Vaiana–Rosati model for complex rate-independent mechanical hysteresis phenomena
No full textEnhanced solution strategies for the ultimate strength analysis of composite steel-concrete sections subject to axial force and biaxial bending
No full textWe present a family of algorithms for evaluating the ultimate limit state of composite and reinforced concrete (RC) sections of arbitrary polygonal or circular shape, either simple or multicell, subject to axial force and biaxial bending. All algorithms are based upon a secant strategy for computing the stiffness matrix used in the equilibrium iterations while they differ in the scheme adopted to estimate the ultimate values of axial force and bending moments. In this respect they enhance in several ways two analogous algorithms presented in a previous paper [L. De Vivo, L. Rosati, Ultimate strength analysis of reinforced concrete sections subject to axial force and biaxial bending, Comput. Methods Appl. Mech. Engrg. 166 (1998) 261–287] for reinforced concrete sections. First, it is shown the specialization of some new formulas, proved elsewhere, for evaluating the entries of the secant stiffness matrix solely as function of the position vectors of the vertices of the section, assumed to be polygonal, and of the constitutive parameters of the nonlinear stress–strain laws for the materials. Second, the case of sections made of or containing either circles or segments of circular arc is exactly taken into account without the need of approximating such shapes by polygons. Third, the extensive numerical tests carried out for a wide range of RC sections and for a benchmark steel–concrete section have shown that the convergence rate and the stability of the new algorithms considerably increase with respect to the ones presented in De Vivo and Rosati (1998). As outcome of the numerical experiments, two solution strategies have been selected as the optimal ones since they combine both global convergence and a satisfactory convergence rate
Paolo Rosati, “ArchaeoloGIS” a QGIS plugin for archaeological spatial analysis
No full textArchaeoloGIS is a QGIS plugin for very basic archaeological spatial analysis. It was inspired by the accurate studies in geography, methodology and digital humanities made by the author during the years of his participation in the ERC project PAThs. The Archaeological Atlas of the Coptic Literature (https://atlas.paths-erc.eu). The first steps were taken from the studies of the road network named MOvEIT (https://paths-erc.eu/moveit/, Bogdani 2023). The coding phase started in the winter of 2021 and the validation on the practical applications presented below were carried out during the spring of the next year. The plugin is GPL-3.0 licensed and can be freely installed from the official repository (https://github.com/archeorosati/archaeoloGIS). It is developed as a QGIS Processing Toolbox script, it is still in beta version and suggestions and questions from the community are welcomed. At present, it consists of a unique script named Tabula Peutingeriana after the famous imperial Roman map, able to output points at a regular, fixed distance of a Roman mile along a path or network of paths. It can be used to position virtual milestones along an already provided road network, eventually help- ing to find the location of original ones, by counting the Roman miles from a given starting point
Rosati, Arre, Platt, & Santos - Study 1
No full textTrial data from Rosati, Arre, Platt, & Santos Study 1 (Negative socioemotional stimuli). Key for variables included as a separate tab in file
Rosati, Arre, Platt, & Santos - Study 2
No full textTrial data from Rosati, Arre, Platt, & Santos Study 2 (Positive socioemotional stimuli). Key for variables included as a separate tab in file
Il sacro nei luoghi. Sull’eredità degli studi di Massimo Rosati
No full textl contributo ricostruisce alcuni punti salienti dell'analisi teorica proposta dal sociologo italiano Massimo Rosati sullo spazio sacro. Adottando una prospettiva pienamente durkheimiana, Rosati discute come lo spazio rifletta e contribuisca ai sistemi di classificazione simbolica che organizzano la vita sociale e morale e che poggiano, essenzialmente, sulla distinzione sacro-profano. Secondo Rosati, il simbolismo religioso non ha smesso di riempire di significato l'organizzazione morfologica degli spazi sociali e di informare il complesso tessuto delle città moderne. Allo stesso tempo, in contesti plurali, i simbolismi si moltiplicano e si confrontano. In questo scenario, Rosati ci fornisce domande che investono la stabilità di una possibile grammatica fondamentale dei luoghi sacri
Under the shadow of a big plane tree. Why platanus orientalis should be considered an archaeophyte in Italy
No full textIn Italy, Platanus orientalis L. is judged as an endangered species by some authors and non-native by others: these contrasting assessments can mislead the prioritization of management actions to preserve the species and the riparian vegetation that is its host. Based on a multidisciplinary approach, including palaeobotanical and ecological information, we assessed its status in Italy including the ecological and conservation value of the riparian plant communities hosting it in the Cilento National Park (S-Italy). Palaeobotanical data showed that P. orientalis in Italy should be considered an archaeophyte. According to the ecological assessment of the riparian plant communities hosting P. orientalis, the presence of the species can be interpreted as an indicator of an unfavourable state for the conservation of riparian vegetation. Knowing the status of a species remains one of the first steps to take to correctly propose scientifically based solutions for the conservation of plant diversity. However, there are no absolute criteria for conservation because all conservation objectives can be considered as cultural values. In this context, P. orientalis should be protected as a symbolic tree, an archaeophyte testifying an ancient common Mediterranean cultural heritage, worthy of preservation but outside of natural habitats
Phytosociological study of fringe communities of Sardinia (Italy)
No full textQuestion: This study represents the first contribution to the description and ecological characterization of fringe communities of Sardinia (Italy), and aimed: 1) to describe Sardinian fringe communities from a floristic vegetational point ; 2) to provide a syntaxonomic scheme, confirming or not the applicability of the most recent framework, proposed at the European scale, also in a Mediterranean insular context (Sardinia); 3) to verify if there is a correspondence among fringe communities and potential natural vegetation in the study area. Study area: Sardinia, the second largest island of the Mediterranean basin (Italy). Methods: 65 phytosociological plots realized using the Braun-Blanquet approach; for each of them, bioclimatic indices were derived from the available Bioclimatic map of Sardinia; Raunki??r life-forms were considered as species functional traits. Furthermore, by using Ellenberg Indicator Values (EIVs) we calculated for each relev?? an abundance-weighted mean indicator value. Main vegetation types were identified through a Hierarchical Cluster Analysis (HCA) and NMDS ordination. A permutational multivariate analysis of variance was used to test the overall significance in EIVs distribution differences among the clusters obtained from HCA. Results: we found a total amount of 139 vascular plant species. Hierarchical clustering detected the presence of seven interpretable clusters, well differentiated in terms of floristic composition, geographic distribution, bioclimatic characters and EIVs, and in terms of their inclusion in different vegetation series. Conclusions: we describe 5 new associations, four of them included in the new alliance Digitalido purpureae-Pteridion aquilini (Melampyro-Holcetalia mollis order, Trifolio-Geranietea sanguinei class), clearly differentiated with respect to other alliances described from both the eastern and the western side of the Tyrrhenian Sea. Another new association was referred to the Epilobietea angustifolii class (Galio-Alliarietalia order)
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