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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
201

Continuous geochemical monitoring by mass-spectometer in the Campi Flegrei geothermal area. An application at Pisciarelli-Solfatara (diffuse and fumarolic gases) and at the mud gases during drilling of the CFDDP pilot hole

Fedele, Alessandro <1984> 22 February 2013 (has links)
During this work has been developed an innovative methodology for continuous and in situ gas monitoring (24/24 h) of fumarolic and soil diffusive emissions applied to the geothermal and volcanic area of Pisciarelli near Agnano inside the Campi Flegrei caldera (CFc). In literature there are only scattered and in discrete data of the geochemical gas composition of fumarole at Campi Flegrei; it is only since the early ’80 that exist a systematic record of fumaroles with discrete sampling at Solfatara (Bocca Grande and Bocca Nuova fumaroles) and since 1999, even at the degassing areas of Pisciarelli. This type of sampling has resulted in a time series of geochemical analysis with discontinuous periods of time set (in average 2-3 measurements per month) completely inadequate for the purposes of Civil Defence in such high volcanic risk and densely populated areas. For this purpose, and to remedy this lack of data, during this study was introduced a new methodology of continuous and in situ sampling able to continuously detect data related and from its soil diffusive degassing. Due to its high sampling density (about one measurement per minute therefore producing 1440 data daily) and numerous species detected (CO2, Ar, 36Ar, CH4, He, H2S, N2, O2) allowing a good statistic record and the reconstruction of the gas composition evolution of the investigated area. This methodology is based on continuous sampling of fumaroles gases and soil degassing using an extraction line, which after undergoing a series of condensation processes of the water vapour content - better described hereinafter - is analyzed through using a quadrupole mass spectrometer
202

Locating the source of volcanic tremor at stromboli volcano, italy

Longobardi, Mariantonietta <1983> 22 February 2013 (has links)
We have developed a method for locating sources of volcanic tremor and applied it to a dataset recorded on Stromboli volcano before and after the onset of the February 27th 2007 effusive eruption. Volcanic tremor has attracted considerable attention by seismologists because of its potential value as a tool for forecasting eruptions and for better understanding the physical processes that occur inside active volcanoes. Commonly used methods to locate volcanic tremor sources are: 1) array techniques, 2) semblance based methods, 3) calculation of wave field amplitude. We have choosen the third approach, using a quantitative modeling of the seismic wavefield. For this purpose, we have calculated the Green Functions (GF) in the frequency domain with the Finite Element Method (FEM). We have used this method because it is well suited to solve elliptic problems, as the elastodynamics in the Fourier domain. The volcanic tremor source is located by determining the source function over a regular grid of points. The best fit point is choosen as the tremor source location. The source inversion is performed in the frequency domain, using only the wavefield amplitudes. We illustrate the method and its validation over a synthetic dataset. We show some preliminary results on the Stromboli dataset, evidencing temporal variations of the volcanic tremor sources.
203

Biomedicine and pain

Arnaudo, Elisa <1985> 03 May 2013 (has links)
The focus of my research is on contemporary biomedical construction of pain as an object, i.e. the different ways in which pain has been conceptualized and approached as a specific site of investigation in biomedicine. A significant shift in the scientific conception of pain occured in the second half of XXth century. In 1965, Ronald Melzack and Patrick D. Wall propose the Gate Control theory of pain mechanism. This theory denies a fixed and direct relationship between stimulus and pain perception, and emphazises the role played by psychological factors in pain. The IASP utilizes this perspective on the phenomenon, describing pain as “an unpleasant sensory and emotional experience associated to an actual or potential tissue damage or described in the terms of such a damage.” The relationship between pain and damage is pivotal in the definition of pain as a pathological entity. In particular, the biomedical approach to pain appears to be strongly characterized by a dualistic view of its aetiology. Disease conceptions such as “psychogenic pain” and chronic pain are deeply influenced by the ways in which psychological factors have been interpreted as components, or as causes of pain. In the second part of my dissertation, I focus on fibromyalgia, which is emblematic of the problematic acknowledgment of chronic pain as a disease. Even if fibromyalgia is actually treated in Rheumatology, its status as a disease is blurred, mainly because of its complex symptomatology including both physiological manifestations and psychological ones. In the conclusion, I present a scenario of the different ways in which this disease is dealt with in biomedical knowledge, through medical literature, clinical practice, and patients’ accounts. The findings of an ethnographic enquiry in the Rheumatology Division of a local clinic and a visual research on patients’ experiences are analyzed and discussed.
204

Il ruolo della metafora nella comunicazione della fisica contemporanea / The role of metaphor in communication of contemporary physics

Ceroni, Gabriele <1969> 03 May 2013 (has links)
Il presente lavoro si rivolge all’analisi del ruolo delle forme metaforiche nella divulgazione della fisica contemporanea. Il focus è sugli aspetti cognitivi: come possiamo spiegare concetti fisici formalmente complessi ad un audience di non-esperti senza ‘snaturarne’ i significati disciplinari (comunicazione di ‘buona fisica’)? L’attenzione è sulla natura stessa della spiegazione e il problema riguarda la valutazione dell’efficacia della spiegazione scientifica a non-professionisti. Per affrontare tale questione, ci siamo orientati alla ricerca di strumenti formali che potessero supportarci nell’analisi linguistica dei testi. La nostra attenzione si è rivolta al possibile ruolo svolto dalle forme metaforiche nella costruzione di significati disciplinarmente validi. Si fa in particolare riferimento al ruolo svolto dalla metafora nella comprensione di nuovi significati a partire da quelli noti, aspetto fondamentale nel caso dei fenomeni di fisica contemporanea che sono lontani dalla sfera percettiva ordinaria. In particolare, è apparsa particolarmente promettente come strumento di analisi la prospettiva della teoria della metafora concettuale. Abbiamo allora affrontato il problema di ricerca analizzando diverse forme metaforiche di particolare rilievo prese da testi di divulgazione di fisica contemporanea. Nella tesi viene in particolare discussa l’analisi di un case-study dal punto di vista della metafora concettuale: una analogia di Schrödinger per la particella elementare. I risultati dell’analisi suggeriscono che la metafora concettuale possa rappresentare uno strumento promettente sia per la valutazione della qualità delle forme analogiche e metaforiche utilizzate nella spiegazione di argomenti di fisica contemporanea che per la creazione di nuove e più efficaci metafore. Inoltre questa prospettiva di analisi sembra fornirci uno strumento per caratterizzare il concetto stesso di ‘buona fisica’. Riteniamo infine che possano emergere altri risultati di ricerca interessanti approfondendo l’approccio interdisciplinare tra la linguistica e la fisica. / The present work deals with the role of metaphorical thinking in the public communication of contemporary physics. We focus on the cognitive aspects: how to disseminate complicated formal physical concepts to a non-professional public maintaining the ‘correct’ disciplinary meaning, that is aiming at communication of ‘good physics’. The focus is on the nature of the explanation and the problem is how to evaluate the effectiveness of public scientific explanation of advanced physical topics to a non-professional audience. For this purpose we have looked for formal tools apt at analyzing the linguistic features of dissemination texts. We have drawn our attention to the role of analogical and metaphorical forms in the construction of ‘actual’ physical meanings because they obviously play an important role in introducing new concepts from previous ones when dealing with contemporary physics phenomena that are far from the ordinary perceptive domain. For the purpose of our investigation the conceptual metaphor perspective, within the framework of cognitive linguistics, appeared to be the most promising analytical tool. We investigate the research problem by analyzing a set of ‘relevant’ analogies and metaphors taken from popular science literature. In particular an analysis of a case study, within the framework of conceptual metaphor, is presented : Schrödinger’s analogy for ‘elementary particle’. The results of the analysis suggest that the conceptual metaphor perspective might be a potential tool both to assess the quality of analogical forms used in explanation of contemporary physics and to design new and ‘better’ analogies and metaphors. Besides, in a recursive process this analysis could help to focus on those meaningful cognitive aspects that characterize, and refine, a ‘complete’ and ‘correct’ physical concept. We think that fruitful results of inquiry might come from a deeper interdisciplinary approach between linguistics and physics.
205

La valutazione della ricerca scientifica: Uno studio empirico nelle Scienze umane / Evaluation of scientific research: an empirical study in the humanities

Piazza, Stefano <1968> 24 October 2013 (has links)
Nel corso degli ultimi anni si è assistito ad un ampio dibattito sull’uso della valutazione della ricerca nelle università e nelle strutture di ricerca. Nell’ambito di tale dibattito, nella presente tesi, vengono analizzate le più importanti metodologie per la valutazione della ricerca presenti a livello internazionale, i principali strumenti qualitativi di valutazione della ricerca (in particolare la peer review), gli strumenti quantitativi, quali la bibliometria, e le caratteristiche dei più importanti archivi bibliografici citazionali (es. Scopus, Web of Science), approfondendo i principali indicatori citazionali utilizzati nelle scienze umane e sociali (es. Indice H). Inoltre la tesi affronta il tema dell’impatto socio-economico della ricerca e le principali criticità di questo innovativo strumento, attraverso uno studio di caso realizzato nel Regno Unito. Una successiva analisi empirica riguarda le principali liste di riviste realizzate a livello internazionale e nazionale, nel settore scientifico di Storia e Filosofia della scienza. I risultati degli studi mostrano che le liste internazionali di riviste possono rappresentare, un punto di partenza a cui devono necessariamente essere affiancati altri strumenti di valutazione (peer review, analisi citazionali, etc); mentre le liste nazionali rischiano, invece, di essere uno strumento poco utile ed in alcuni casi inadeguato al fine di una corretta valutazione della ricerca, a causa della scarsa internazionalizzazione dei repertori e dei giudizi generalmente troppo elevati attribuiti alle riviste. Un ulteriore risultato raggiunto nella presente tesi riguarda la valutazione della ricerca nelle diverse discipline scientifiche: nelle Scienze umane e sociali risulta esserci uno scarso grado di presenza di pubblicazioni scientifiche nei principali archivi bibliografici e citazionali internazionali. Questa situazione limita fortemente l’attendibilità delle analisi statistiche basate su indici e indicatori quantitativi, per valutare la produttività scientifica di un ricercatore, oppure di una istituzione di ricerca. / Over the last few years there has been an extensive debate on the use of evaluation of research in universities and research facilities. As part of this debate, in this thesis, we analyze the most important methods for the assessment of research on an international level, the main qualitative tools for the evaluation of research, in particular the peer review, and quantitative tools, such as bibliometrics, and the characteristics of the main bibliographic archives (eg, Scopus, Web of Science), deepening the main indicators used in human and social sciences (eg H Index). In addition, the thesis is connected with the socio-economic impact of research and the main problems of this innovative tool, through a case study conducted in the United Kingdom. A subsequent empirical analysis covers the main lists of journals at international and national levels, in the scientific field of History and Philosophy of Science. The results of the studies show that the lists of international journals can be, a starting point which must necessarily be joined by other instruments of assessment (peer review, citation analysis, etc.), while the national lists, however, can’t be an instrument, which is in some cases inadequate in order to a proper evaluation of the research, due to the low internationalization of repertoires and judgments generally too high attributed to the journals. A further result is that the evaluation of research in different scientific disciplines shows that in the humanities and social sciences there is a low presence of scientific publications in major international citation and bibliographic databases (Web of Science, Scopus). This situation limits the reliability of the statistical analysis based on indices and quantitative indicators (first Impact Factor and Index H), to evaluate the scientific productivity of a researcher or an institution research.
206

Formazione e pratica del pensiero orchestrale di Hector Berlioz. Caratteri poetici e strategie del suono / Development and practice of Hector Berlioz’s orchestral thought. Poetical features and sound strategies

Valenti, Paolo <1977> 09 September 2014 (has links)
Lo scopo della dissertazione “Formazione e pratica del pensiero orchestrale di Hector Berlioz. Caratteri poetici e strategie del suono” è quello di indagare i tratti essenziali del pensiero di Berlioz in merito all’orchestra riprendendo in considerazione gli elementi della sua educazione giovanile. In particolare, le nozioni ricavate dai suoi insegnanti di composizione Le Sueur e Reicha e dai corsi di medicina brevemente frequentati a Parigi sono indagate con approccio rinnovato, alla luce di nuovi filoni di studio indagati dalla musicologia negli anni più recenti. Sono analizzate anche le recensioni di Berlioz, alla ricerca di elementi che aiutino a comprendere la sua musica con le argomentazioni destinate a quella altrui. È analizzato anche il percorso della trattatistica che da un iniziale approccio di tipo pratico tipico del XVIII secolo, giunge con il trattato di Berlioz a una forte connotazione poetica delle risorse strumentali e orchestrali. Nella seconda parte della dissertazione sono analizzate invece alcune opere di Berlioz e alcune questioni generali concernenti il suo modo di scrivere per l’orchestra, specialmente in relazione ad altri parametri musicali. Nella dissertazione notevole attenzione è data al rapporto fra questioni tecniche e poetiche, proponendo un approccio leggermente rinnovato. / The purpose of the dissertation “Development and practice of Hector Berlioz’s orchestral thought. Poetical features and sound strategies” is to investigate the main traits of Berlioz’s thinking about orchestra by reconsidering the elements of his early education. In particular, the notions acquired from his composition teachers Le Sueur and Reicha and from the medicine courses he briefly attended are examined with a renovated approach, in the light of new lines of study explored by musicology in recent years. Berlioz’s reviews are also analyzed, in the search of elements useful to understand his music through the arguments addressed to others’ music. The dissertation also examines the itinerary of theoretic music literature which, from an initial approach connoted by practice as it was typical in the 18th century, reaches with Berlioz’s treaty a strong poetical connotation of instrumental and orchestral resources. The second part of the dissertation deals with some of Berlioz’s works and with some general issues related to his way of writing for the orchestra, especially in relation to other musical parameters. In the whole discussion, sensible attention is put on the relation between technical and poetical issues, suggesting a quite renovated approach.
207

Evaluation of slope stability under water and seismic load through the Minimum Lithostatic Deviation method

Paparo, Maria Ausilia <1983> 07 May 2014 (has links)
The main objective of this thesis is to obtain a better understanding of the methods to assess the stability of a slope. We have illustrated the principal variants of the Limit Equilibrium (LE) method found in literature, focalizing our attention on the Minimum Lithostatic Deviation (MLD) method, developed by Prof. Tinti and his collaborators (e.g. Tinti and Manucci, 2006, 2008). We had two main goals: the first was to test the MLD method on some real cases. We have selected the case of the Vajont landslide with the objective to reconstruct the conditions that caused the destabilization of Mount Toc, and two sites in the Norwegian margin, where failures has not occurred recently, with the aim to evaluate the present stability state and to assess under which conditions they might be mobilized. The second goal was to study the stability charts by Taylor and by Michalowski, and to use the MLD method to investigate the correctness and adequacy of this engineering tool.
208

Advanced modelling of time domain electromagnetic data with updated hydrogeological interpretations

Sapia, Vincenzo <1982> 07 May 2014 (has links)
Several countries have acquired, over the past decades, large amounts of area covering Airborne Electromagnetic data. Contribution of airborne geophysics has dramatically increased for both groundwater resource mapping and management proving how those systems are appropriate for large-scale and efficient groundwater surveying. We start with processing and inversion of two AEM dataset from two different systems collected over the Spiritwood Valley Aquifer area, Manitoba, Canada respectively, the AeroTEM III (commissioned by the Geological Survey of Canada in 2010) and the “Full waveform VTEM” dataset, collected and tested over the same survey area, during the fall 2011. We demonstrate that in the presence of multiple datasets, either AEM and ground data, due processing, inversion, post-processing, data integration and data calibration is the proper approach capable of providing reliable and consistent resistivity models. Our approach can be of interest to many end users, ranging from Geological Surveys, Universities to Private Companies, which are often proprietary of large geophysical databases to be interpreted for geological and\or hydrogeological purposes. In this study we deeply investigate the role of integration of several complimentary types of geophysical data collected over the same survey area. We show that data integration can improve inversions, reduce ambiguity and deliver high resolution results. We further attempt to use the final, most reliable output resistivity models as a solid basis for building a knowledge-driven 3D geological voxel-based model. A voxel approach allows a quantitative understanding of the hydrogeological setting of the area, and it can be further used to estimate the aquifers volumes (i.e. potential amount of groundwater resources) as well as hydrogeological flow model prediction. In addition, we investigated the impact of an AEM dataset towards hydrogeological mapping and 3D hydrogeological modeling, comparing it to having only a ground based TEM dataset and\or to having only boreholes data.
209

Earthquake forecasting and seismic hazard analysis: some insights on the testing phase and the modeling

Taroni, Matteo <1984> 07 May 2014 (has links)
This thesis is divided in three chapters. In the first chapter we analyse the results of the world forecasting experiment run by the Collaboratory for the Study of Earthquake Predictability (CSEP). We take the opportunity of this experiment to contribute to the definition of a more robust and reliable statistical procedure to evaluate earthquake forecasting models. We first present the models and the target earthquakes to be forecast. Then we explain the consistency and comparison tests that are used in CSEP experiments to evaluate the performance of the models. Introducing a methodology to create ensemble forecasting models, we show that models, when properly combined, are almost always better performing that any single model. In the second chapter we discuss in depth one of the basic features of PSHA: the declustering of the seismicity rates. We first introduce the Cornell-McGuire method for PSHA and we present the different motivations that stand behind the need of declustering seismic catalogs. Using a theorem of the modern probability (Le Cam's theorem) we show that the declustering is not necessary to obtain a Poissonian behaviour of the exceedances that is usually considered fundamental to transform exceedance rates in exceedance probabilities in the PSHA framework. We present a method to correct PSHA for declustering, building a more realistic PSHA. In the last chapter we explore the methods that are commonly used to take into account the epistemic uncertainty in PSHA. The most widely used method is the logic tree that stands at the basis of the most advanced seismic hazard maps. We illustrate the probabilistic structure of the logic tree, and then we show that this structure is not adequate to describe the epistemic uncertainty. We then propose a new probabilistic framework based on the ensemble modelling that properly accounts for epistemic uncertainties in PSHA.
210

La gestione dell'acqua come oggetto d'indagine per la ricostruzione delle dinamiche insediamentali e delle trasformazioni del territorio. Il caso di Samarcanda nella Media Valle dello Zeravshan (Uzbekistan) / Settlement Dynamics and Water Management for the Reconstruction of the Landscape Transformations: A Case Study form the Middle Zeravshan Valley (Samarkand, Uzbekistan)

Mantellini, Simone <1974> 05 June 2009 (has links)
The Project dealt with the development of settlement pattern and the irrigation system in Samarkand oasis. The main topic of the research is the dating of the Dargom canal, the main water supply of Samarkand in the ancient times as well as today. The Project provided a new hypothesis on the chronology of Dargom, dated back to the Early centuires of the Current Era, in relation with the different phases of the settlement patterns. The researches were carried out with several international teams and schoalrs belonging to several disciplines.

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