Search results for " trees."
showing 10 items of 207 documents
Impoverishment of Sicilian (Italy) historical and cultural assets by an alien insect species:the case study of the Real Palm Weevil
2012
Microorganisms and insects have a disastrous impact on the biodiversity, cultural heritage and economy of a geographic area. However, in recent decades, the negative effects of invasive alien species (IAS), including both animal and plant or microorganisms occurring outside their natural distribution range, are generally not well known. Invasive alien species are most often found in or near urban areas, as well as throughout the settled landscape. According to the World Conservation Union, IUCN 2012, IAS represent the second most significant threat to biodiversity after resource depletion of habitats, becoming predators, competitors, parasites, hybridizers and diseases for native plants and…
Schede per il censimento degli alberi monumentali di Sicilia. 37-43
2013
The reports 37-50 concerning unpublished monumental trees sur- veyed in Sicily are here presented. They are: the Cherry tree of Ciccio Faranda, the Almond tree of Corte del Sole [Prunus dulcis (Mill.) D. A. Webb var. dulcis], the Olive trees (Olea europaea L. var. europaea) in the following lands: Innari, Maviti, Misilmeri and Favorita Park; the Common pear (Pyrus communis L.) of the Pistacchiera.
Words, Trees and Automata Minimization
2013
In this paper we explore some connections between some combinatorial properties of words and the study of extremal cases of the automata minimization process. An intermediate role is played by the notion od word trees for which some properties of words are generalized. In particular, we describe an infinite family of binary automata, called word automata and constructed by using standard sturmian words and more specifically Fibonacci words, that represent the extremal case of some well known automata minimization algorithms, such as Moore’s and Hopcroft’s methods. As well as giving an overview of the main results in this context, the main purpose of this paper is to prove that, even if a re…
Image Segmentation through a Hierarchy of Minimum Spanning Trees
2012
Many approaches have been adopted to solve the problem of image segmentation. Among them a noticeable part is based on graph theory casting the pixels as nodes in a graph. This paper proposes an algorithm to select clusters in the images (corresponding to relevant segments in the image) corresponding to the areas induced in the images through the search of the Minimum Spanning Tree (MST). In particular is is based on a clustering algorithm that extracts clusters computing a hierarchy of Minimum Spanning Trees. The main drawback of this previous algorithm is that the dimension of the cluster is not predictable and a relevant portion of found clusters can be composed by micro-clusters that ar…
Uomini e alberi. Tre indagini storico-religiose. Nota introduttiva
2021
In this introductory note I present three essays on the relationship between trees and rituals in ancient Mediterranean civilisations and in Vedic India.
Dendrolatrie. Miti e pratiche dell'immaginario arboreo
2021
L’avvento dell’Antropoce, epoca in cui l’essere umano è diventato una forza geologica, scompagina la divisione del sapere tra scienze umane e naturali. Per comprenderlo, è necessario costruire nuove forme di alleanza tra discipline. È quanto invita a fare anche il fe- nomeno delle dendrolatrie. Diffuso in ogni luogo e in ogni epoca, il culto degli alberi testimonia come il mondo arboreo abbia plasma- to modi di vivere e di pensare, venendone a sua volta trasformato. Per scavare nella complessità di questo scambio, il volume racco- glie i frutti del dialogo tra un gruppo interdisciplinare di ricercatrici e ricercatori che esplorano l’immaginario arboreo in tre direzioni: quella degli studi s…
[Deciding in conditions of uncertainty: the Delphi method and its use in the formulation of guidelines].
2001
The purpose of this paper is to analyze one of the most powerful tools in the decision-making under conditions of uncertainty, the Delphi method, and to verify the related interest of scientific world, particularly, for formulation of guidelines. The method combines the expert opinion preventing biases due to institutional role, status or dominant personality. In the text we explain the methodology and the steps through which it is possible to realize the consensus; we schematized in a didactic manner all the phases for an operational approach of the reader. The search by the most diffused biomedical database (Medline) individualized 623 citations, 7 of which are guidelines (3 of remarkable…
Evaluation of Risk Parameters in Bone Regeneration Using a Customized Titanium Mesh
2019
PURPOSE The aim of the study was an evaluation of risk factors for an innovative bone regeneration technique using a customized titanium mesh that was tested in a clinical setting. MATERIALS AND METHODS This retrospective study included 65 patients with 70 grafting procedures of osseous defects of the jaws with a customized titanium mesh together with Advanced- and Injectable-Platelet-Rich Fibrin (A- and I-PRF), resorbable membranes, and bone grafting materials. Exposures of the meshes and grafting outcome were analyzed according to a novel classification as (a) punctual and (b) tooth width or complete exposure of the mesh (c). No exposure was stated as (d). RESULTS In 37% of cases, exposur…
Pruning Incremental Linear Model Trees with Approximate Lookahead
2014
Incremental linear model trees with approximate lookahead are fast, but produce overly large trees. This is due to non-optimal splitting decisions boosted by a possibly unlimited number of examples obtained from a data source. To keep the processing speed high and the tree complexity low, appropriate incremental pruning techniques are needed. In this paper, we introduce a pruning technique for the class of incremental linear model trees with approximate lookahead on stationary data sources. Experimental results show that the advantage of approximate lookahead in terms of processing speed can be further improved by producing much smaller and consequently more explanatory, less memory consumi…
Networks of equities in financial markets
2004
We review the recent approach of correlation based networks of financial equities. We investigate portfolio of stocks at different time horizons, financial indices and volatility time series and we show that meaningful economic information can be extracted from noise dressed correlation matrices. We show that the method can be used to falsify widespread market models by directly comparing the topological properties of networks of real and artificial markets.