Search results for "gg"

Enhancing Metastability by Dissipation and Driving in an Asymmetric Bistable Quantum System.

2018

The stabilizing effect of quantum fluctuations on the escape process and the relaxation dynamics from a quantum metastable state are investigated. Specifically, the quantum dynamics of a multilevel bistable system coupled to a bosonic Ohmic thermal bath in strong dissipation regime is analyzed. The study is performed by a non-perturbative method based on the real-time path integral approach of the Feynman-Vernon influence functional. We consider a strongly asymmetric double well potential with and without a monochromatic external driving, and with an out-of-equilibrium initial condition. In the absence of driving we observe a nonmonotonic behavior of the escape time from the metastable regi…

Riflessioni metodologiche geografiche sul quartiere. Tra frontiere invisibili e barriere visibili

2012

Problem solving e metacognizione. L’uso didattico del prompt per sviluppare strategie di problem solving nei futuri maestri

2015

Si presentano i risultati di una ricerca che ha coinvolto in totale 235 studenti del corso di Laurea in Scienze della Formazione Primaria dell’Università di Palermo. Con la ricerca si è inteso individuare le metodologie di sostegno atte a promuovere nei futuri maestri da una parte la capacità di identificare e affrontare situazioni scolastiche problematiche in modo adeguato; dall’altra la capacità di riflettere metacognitivamente sul processo di risoluzione del problema. La ricerca costituisce un esempio di come si possa sviluppare nei futuri insegnanti in formazione quell’insieme di abilità cognitive e metacognitive che confluiscono nella capacità di identificare e risolvere situazioni edu…

Sviluppo di un sistema di monitoraggio per lo studio delle dinamiche meteorologiche nell'area urbana di Palermo.'

2013

Use of fragmentation beams at LNS with CHIMERA detector

2012

The recent intensity upgrade of the LNS fragmentation beam is discussed. The available beams, the tagging procedures and details on the beam quality are reported. The experimental program started with the CHIMERA detector using such beams is also discussed with preliminary results and future perspectives. © Owned by the authors, 2012.

DEM-resolution control on rainfall-triggered landslide modeling within a triangulated network-based model

2019

Catchment slope distribution significantly controls rainfall-triggered landslide modeling, in both direct and indirect ways. Slope directly determines the soil volume associated with instability. Indirectly, it affects the subsurface lateral redistribution of soil moisture across the basin, which in turn determines the water pore pressure conditions that impact slope stability. It is thus clear that the accuracy in reproducing slope distribution may be crucial in slope stability analysis. The resolution of the Digital Elevation Model (DEM) regulates the description of the topography. The correlation between raster resolution and landslide model outputs has been investigated in the literatur…

Application of selected supervised classification methods to bank marketing campaign

2016

Supervised classification covers a number of data mining methods based on training data. These methods have been successfully applied to solve multi-criteria complex classification problems in many domains, including economical issues. In this paper we discuss features of some supervised classification methods based on decision trees and apply them to the direct marketing campaigns data of a Portuguese banking institution. We discuss and compare the following classification methods: decision trees, bagging, boosting, and random forests. A classification problem in our approach is defined in a scenario where a bank’s clients make decisions about the activation of their deposits. The obtained…

ENSEMBLE METHODS FOR RANKING DATA

2017

The last years have seen a remarkable flowering of works about the use of decision trees for ranking data. As a matter of fact, decision trees are useful and intuitive, but they are very unstable: small perturbations bring big changes. This is the reason why it could be necessary to use more stable procedures, as ensemble methods, in order to find which predictors are able to explain the preference structure. In this work ensemble methods as BAGGING and Random Forest are proposed, from both a theoretical and computational point of view, for deriving classification trees when ranking data are observed. The advantages of these procedures are shown through an example on the SUSHI data set.

Ensemble methods for ranking data with and without position weights

2020

The main goal of this Thesis is to build suitable Ensemble Methods for ranking data with weights assigned to the items’positions, in the cases of rankings with and without ties. The Thesis begins with the definition of a new rank correlation coefficient, able to take into account the importance of items’position. Inspired by the rank correlation coefficient, τ x , proposed by Emond and Mason (2002) for unweighted rankings and the weighted Kemeny distance proposed by García-Lapresta and Pérez-Román (2010), this work proposes τ x w , a new rank correlation coefficient corresponding to the weighted Kemeny distance. The new coefficient is analized analitically and empirically and represents the main…

La Sicilia in Cina. Una raccolta di testi cinesi sull’isola (1225-1911)

2019

Pochi sanno che la Sicilia è stata la prima regione italiana a essere descritta in un testo cinese. Questo avvenne nel 1225 e l’autore di tale descrizione fu un doganiere che raccolse notizie sulle nazioni e le genti straniere dai mercanti che sbarcavano sulle coste cinesi. Da quel momento in poi numerosi sono stati gli autori che hanno descritto la Sicilia in Cina, studiosi cinesi e missionari occidentali desiderosi di far conoscere il mondo occidentale. Le conoscenze sulla Sicilia sono andate ampliandosi e arricchendosi di dettagli, rivelando un sincero interesse per questa terra, centro del Mediterraneo e culla della cultura classica. Attraverso un’antologia di testi che spaziano dal 120…