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Intersezione e unione di matroidi
No full textLo scopo principale di questa tesi è sviluppare una ristesura del paper “Amatroid intersection algorithm” a cura di Gyula Pap, in modo da renderne più accessibile la comprensione
A statistical ecology approach to upscale human activity data
No full textIn the present work we will adopt a statistical framework which was firstly designed in ecology to get new insights into human activities databases with the aim of inferring global statistics of a data set from a random sample of it. This dissertation closely follows the PhD thesis[9] and the article [10
A stochastic model for immunotherapy of cancer
Get PDFIn recent years, the use of mathematics in cancer research has caught on, with the rapid accumulation of data and applications of mathematical methodologies. The application of mathematics in cancer research is known as *mathematical oncology*. Mathematical oncology, starting from theoretical studies, tries to design clinical experiments with mathematical models. Mathematical models represent an useful tool for an interdisciplinary approach to cancer research. Indeed, various points of view, coming from several scientific areas, are fundamental to face the complexity of cancer evolution. In this setting, cancer ecology arises as promising quantitative approach. Cancer ecology looks at different groups
of cells in an organism as interacting species of an ecosystem. From this perspective, cancer cells are a new species appearing in a stable ecosystem. Cancer cells represent a harmful and invasive species, abling to influence and change the interaction among the different types of healthy cells, that represent the pre-existing species. To promote their growth, cancer cells trigger a struggle for survival, which can lead to the extinction of certain types of cells and, in the worst cases, to the collapse of the entire ecosystem. The stochastic models (specially interacting particle systems) fit the noisy dynamics of cancer. One of the main problematic features of cancer is therapy resistance. Among therapies, immunotherapy represents a potential and effective treatment for patients with certain types of resistant cancer. Moreover a wide range of cancers are currently treated using immunotherapy; in particular melanoma has a good response to this kind of treatment. Therefore, in this thesis, we have chosen a stochastic model for immunotherapy of cancer. In particular the proposed model allows to simulate different treatment protocols, highlighting some counter-intuitive results: under some particular conditions therapy could work in favour of cancer resistance. Accordingly, the same type of cancer acts in very different ways with respect to the affected person and used therapy. Therefore, mathematical oncology could play a decisive role in the future of personalized medicine. In fact, patient-specific mathematical modelling, analysis and collection of clinical data could represent effective tools to develop patient-specific adaptive therapies and to face therapy resistance
Modalità di corrosione di scambiatori di calore a fascio tubiero utilizzati in processi di evaporazione/condensazione. Corrosion mechanism of shell and tube heat exchangers used in evaporation/condensation processes
Get PDFAnalisi fenomeni corrosione in scambiatori di calore a fascio tubiero
Validazione di una pinza adattiva per la mediazione dell'impatto tra robot e pezzo
No full textIn ottica di una teleoperazione di sortig, realizzare un end-effector capace di mediare l'urto tra robot e pezzo da movimentare. L'end-effector realizzato inoltre, doveva essere in grado di ridurre la velocità del pezzo dopo l'urto
Experimental and numerical investigation for in-depth characterisation of impact-dynamic properties in third generation Advanced High-Strength Steels
Get PDFIl presente lavoro consiste in uno studio sperimentale e in uno studio numerico. Lo scopo di tali studi è quello di migliorare la qualità degli esperimenti dinamici, realizzati tramite la Barra di Hopkinson presso la Ghent University. Nel lavoro sperimentale viene eseguita una calibrazione diretta del sistema di estensimetri necessario a misurare le grandezze della prove. Nel lavoro numerico viene eseguita una otitmizzazione geometrica del provino da testare
Modellazione su modello fisico dello scambio di energia geotermica a bassa entalpia: analisi di dati sperimentali
No full textThe aim of this thesis work is to present an experimental apparatus designed to study the energy exchange that occurs between a geothermal probe and the surrounding environment, under low enthalpy conditions. The physical model in question simulates the behavior of a probe inserted inside a material, which can be granular but also rocky, present in nature. The experimental apparatus has a volume of about 1m3 and is crossed by a thermal probe made of copper; the thermal probe is served by a closed hydraulic circuit. The water flow rate, which passes through the thermal probe, is set as well as the temperature of the fluid. In the granular material (Risetta del Brenta) that fills the experimental apparatus, 24 high precision temperature probes are opportunely distributed. The experimental apparatus can be saturated with water and it is possible to realize a filtration motion by using a second hydraulic circuit. In the present work, a water-free configuration is considered. The first part of the paper is aimed to a detailed description of the physical model and the physical principles governing the heat transfer within it. Subsequently, an analysis of the behavior of the physical model with respect to the ideal case is made highlighting its limitations. The focal point of the paper is the solution of the heat equation in non-stationary conditions in two different configurations: for the flat wall an analytical solution was found, for the case of the hollow cylinder, where this was not possible due to mathematical limitations, a numerical solution had to be used. The validity of the hypotheses and solutions that are proposed is further strengthened by comparing the data obtained through the numerical model with those obtained through the mathematical model. After verifying the truthfulness of the numerical solution, the model is used to estimate the thermal diffusivity of the Brenta Risetta in experimental configuration and, finally, the thermal conductivity coefficient, λ, of experimental material
Study of a cosmic ray detector based on drift tubes
Get PDFMuon tomography is a promising imaging technique for the inspection of dry storage casks (DSC) for spent nuclear fuel. Recently, it has been proposed to implement drift tube detectors to control the content of DSCs. The main objective of this thesis is the analysis of the radial and longitudinal spatial resolution of a drift tube detector. The muon tomography demonstrator installed at Legnaro National Laboratories, consisting of two CMS chambers, has been used to reconstruct the muon tracks and to provide a trigger system for the drift tube. Furthermore, a simulation of the muon flux has been performed to test the optimal position of CMS superlayers with respect to detectors, obtained by joining several layers of drift tubes of the type described in this study, placed around a CASTOR®-V cask
Relazione tra l'approccio ETH alla Meccanica Quantistica e la Decoerenza
Get PDFNella tesi si confrontano l'approccio Event-Tree-History (ETH) alla meccanica quantistica, recentemente proposto, e il formalismo standard della decoerenza. In particolare si analizzano nei due approcci la descrizione della perdita di informazione nel processo di misura e la caratterizzazione degli eventi.
In the thesis Event-Tree-History (ETH) approach to Quantum Mechanics, recently proposed, and the standard formalism of Decoherence are compared. In particular the description of loss of information in the measurement process and the events characterization are analysed within the two approaches
Structure-function relation in a stochastic whole-brain model at criticality
Get PDFUnderstanding the relation between brain architecture and function is one of the central issues in neuroscience nowadays. In the last few years, important efforts have been devoted to map the large-scale structure of the human cortex, the so-called "connectome". An example is the neuroanatomical connectivity matrix of the entire human brain obtained through MR diffusion tractography. Recent studies proposed a stochastic model built on top of this connectivity matrix that displays a phase-transition and is able to reproduce several aspects of brain functioning when tuned to its critical point. This master thesis is aimed to review recent results on this subject and to get a deeper insight into the model by studying the distribution of the avalanches, the dynamical range and to investigate how the use of simulated connectivity matrices affects the dynamics. Furthermore, a theoretical description of the dynamics is proposed by introducing a master equation in order to understand the nature of the phase transition and the role of stochasticity