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Il sito di Arano (Illasi-Verona, scavo 2007) alla luce delle trasformazioni sociali, economiche, tecnologiche, tra età del Rame e Bronzo Antico in Italia settentrionale.
Get PDFL’analisi del sito di Arano si concentra nei primi 5 capitoli. La cronologia delle frequentazioni comprende l’età del Rame e l’antica età del Bronzo, e la quantità di elementi da considerare ed analizzare, nella loro specificità e complessità, è senza dubbio notevole.
Il Capitolo 6 rappresenta il tentativo di enfatizzare l’importanza del dato archeometallurgico, perchè emerso in un contesto così particolare come quello dell’area nord-orientale dell’Italia settentrionale, ricca di depositi minerari conosciuti e sfruttati, ai quali però non è possibile riferire la materia prima con cui sono stati realizzati i materiali in metallo del sito.
Il Cap. 7 riguarda la contestualizzazione della necropoli dell’antica età del Bronzo nel quadro dei pochi rinvenimenti funerari coevi conosciuti in Italia
settentrionale. L’areale e la cronologia portano a riferire Arano alla Cultura di Polada, della quale ho cercato di mettere in evidenza problematiche, lacunosità, contraddizioni. Il Cap. 8 rappresenta, infine, un approfondimento sulle necropoli e i gruppi culturali coevi a nord dell’arco alpino, in particolare quelli stanziati in area danubiano-carpatica, con una selezione necessariamente parziale e soggettiva dei contesti di confronto
An Organizational Approach to the Polysemy Problem in WordNet
No full textPolysemy in WordNet corresponds to various kinds of linguistic phenomena that can be grouped into five classes. One of them is homonymy that refers to the cases, where the meanings of a term are unrelated, and three of the classes refer to the polysemy cases, where the meanings of a term are related. These three classes are specialization polysemy, metonymy, and metaphoric polysemy.Another polysemy class is the compound noun polysemy.
In this thesis, we focus on compound noun polysemy and specialization polysemy.
Compound noun Polysemy corresponds to the cases, where we use the modified noun to refer to a compound noun. Specialization polysemy is a type of related polysemy referring to the polysemy cases, when a term is used to refer to either a more general meaning or a more specific meaning.
Compound noun polysemy and specialization polysemy in WordNet are considered the main reasons behind the highpolysemous nature of WordNet that make WordNet redundant and too fine grained for natural language processing.
Another problem in WordNet is its polysemy representation. WordNet represents the polysemous terms by capturing the different meanings of them at lexical level but without giving emphasis on the polysemy classes these terms belong to.
The highpolysemous nature and the polysemy representation in WordNet affect the usability of it as suitable knowledge representation resource for natural language processing applications. In fact, the polysemy problem in WordNet is a challenging problem for natural language processing applications, especially in the field of information retrieval and semantic search.
To solve this problem, many approaches have been suggested. Although all the state of the art approaches are good to solve the polysemy problem partially, they do not give a general solution for it.
In this thesis, we propose a novel approach to solve the compound noun and specialization polysemy problem in WordNet in the case of nouns.
Solving the compound noun polysemy and the specialization polysemy problem is an important step that enhances the usability of WordNet as a knowledge representation resource.
The proposed approach is not an alternative to the existing approaches. It is a complementary solution for the state of the art approaches especially the systematic polysemy approaches
Lipidomics Investigations in Cell Biology
No full textCell membrane is the biological barrier serving as both territorial defense and the communication hinge for the interior of cell from its surroundings. As building blocks of cellular membranes and also precursor for second messengers, a variety of lipids play essential roles in cellular membrane dynamics as well as important functions such as cell proliferation, apoptosis, signal transduction and membrane trafficking modulation. Lipidomics, representing the systematic and integrative studies of diversified lipids (lipidome) in a biological system, is an emerging yet rapid developing field and hence requires advanced and complementary analytical techniques as well as multiple statistical tools. Our development of reliable analytical methodology (the advanced Mass Spectrometric and high-resolution NMR techniques) and application of multiple statitistical approaches (multivariate data analysis and univariate t-test) enable us to achieve these comprehensive understandings.
We have investigated, first of all, the effects induced by hypoxia on cervical cancer derived cells (HeLa cells) to see how and how much the changes in phospholipids profile are able to get light into the targeted biological problem (hypoxia) and provide a preliminary insight into the underlying mechanisms. We found that hypoxia stimulation dramatically reduced the total amount of cellular phosphoinositols (PI) but prominently increased the amount of lyso phosphocholines (lyso-PC) and lyso phosphoethanolamines (lyso-PE). Moreover, our studies suggested the polyunsaturated phospholipids species as stronger biomarkers upon hypoxia treatment. The evaluation of changes in the average unsaturation index (UI) of the membrane lipids acyl chains revealed that UI slightly increased in several lipid classes, thus affecting membrane fluidity and further membrane-dependent functions. The plausible mechanisms by HeLa cells to adapt to hypoxia conditions are briefly reported as well.
We have also conducted the comparative lipidomic studies of urothelial cancer cell line RT4 (a model system of a benign tumor) and T24 (a model system of a metastatic tumor) aiming to reveal probable roles and relevant differential changes of membrane lipids with respect to urinary bladder metastasis progress. Significant changes of lipids metabolism were found to correlate with urothelial nonmetastatic and metastatic cell models. The most remarkable finding was that the malignant cell type (T24) showed a strong decrease of ether PC species complemented by a sharp increase of the length and the average unsaturation number of lipids acyl chains. Ceramide-based sphinglipids also showed altered profiles in these two cell types. Such analyses suggest a certain significant re-organization of cellular membrane in malignant cell transformation, involving variations in compositional lipid structures and possible signaling transduction pathways. Observations of such reduction of the 1-alkyl PC species and the chain shortening of lipid species might serve as a tool in urinary bladder cancer intervention
Does the Way we interact with Technology Affect Cognitive Performance? An in-depth analysis of writing devices
No full textThe great influence of mass technologies has changed our writing modality that is moving from the traditional use of pen and paper to the domain of keyboards and recently to touchscreen tools, both in everyday life and in educational contexts. The digitalization of writing and of the texts we write, but also the ubiquity of digital technologies, should encourage a deeper understanding of the implications of the physical and sensorimotor changes in writing. It is reasonable to think that the motor-perceptual differences between different writing modalities can lead to different cognitive performances in linguistic tasks, depending on the writing movement that has to be performed but also on the experience that we have with this movement.
In this work, I take into account the role of tangible devices for writing and their different haptic affordance, rarely considered in the study of language, in general, and of writing, in particular. To do so I analyzed different behaviors while we use different writing technologies and discuss the findings from a cognitive science point of view. The general aims of this thesis consists in establishing possible cognitive entailment of different types of writing modalities, in explicating their role in other linguistic tasks and in evaluating the possible implication on daily life and education. The thesis is presented like a collection of papers, results of my research activity and experiences during my participation in the doctoral school. I divided my work in three separate chapters in which different research points of views are analyzed, different experimental procedures are used and different technological devices for writing are tested.
Chapter 1 present a study aimed at investigating whether technologically mediated linguistic performance reflects cross-modal interaction and whether it is modulated by the writing technology used, specifically a touchscreen and a keyboard. Chapter 2 comprises a set of studies dedicated to investigate whether it is possible that a strong experience in typing influences our linguistic abilities. Furthermore, typing and mobile typing are compared testing if the two writing modalities share the same motor behaviors.
Mobile technologies are also the argument of Chapter 3 in which I present two theoretical papers dedicated to the potential of these devices for learning, in general, and for second language learning, in particular
Sediment transport and morphology of braided rivers: steady and unsteady regime
No full textBraided rivers are complex, fascinating fluvial pattern, which represent the natural state of many gravel and sand bed rivers. Both natural and human causes may force a change in the boundary conditions, and consequently impact
the river functionality. Detailed knowledge on the consequent morphological response is important in order to define management strategies which combine different needs, from protection of human activities and infrastructures to preservation of the ecological and biological richness.
During the last decades, research has made significant advance to the description of this complex system, thanks to flume investigations, development of new survey techniques and, to a lesser extent, numerical and analytical solutions of mathematical models (e.g. Ashmore_2013). Despite that, many relevant questions, concerning the braided morphodynamics at different spatial and temporal scales (from the unit process scale, to the reach scale, and eventually to the catchment scale) remain unanswered.
For example, quantitative analysis of the morphological response to varying external controls still requires investigation and needs the definition of suitable, stage-independent braiding indicators. In addition, the morphodynamics of the fundamental processes, such as bifurcations, also needs further analysis of the driving mechanisms. General aim of the present study is to develop new methods to exploit, in an integrated way, the potential of the new possibilities offered by advanced monitoring techniques, laboratory models, numerical schemes and analytical solutions. The final goal is to fill some gaps in the present knowledge, which could ultimately provide scientific support to river management policies. We adopted analytical perturbation approaches to solve the two-dimensional shallow water model; we performed laboratory simulations on a large, mobile-bed flume; we analysed existing topographic measurements from LiDAR and Terrestrial Laser scanning Devices; and we simulated numerically the river hydrodynamics. Within each of the six, independent, research chapters, we interconnected results from the different approaches and methodologies, in order to take advantage of their potential. Summarising, the more relevant and novel outcomes of the present work can be listed as follows: 1) We explored the morphological changes during a sequence of flood events in a natural braided river (Rees River, NZ)and we proposed a morphological method to assess the sediment transport rate. In particular we propose a semi-automatic method for estimating the particles path-length (Ashmore and Church, 1998) on the basis of the size of the deposition patches, which can be identified on the basis of DEM of differences. Comparison with results of numerical simulation confirmed that such an approach can reproduce the response of the bedload rate to floods of different duration and magnitude. 2) We developed a new indicator of the reach-scale morphology and, on the basis of existing laboratory experiments, we explored its dependence, under regime conditions, to the controlling factors: slope, discharge, confinement width, grain size. In spite of its synthetic nature, this simple indicator embeds the information needed to estimate the variability of the Shield stress throughout the braided network, and consequently enables to assess the transport-rate and its variation with the driving discharge. 3) We investigated, through flume experiments, the effect of the flow unsteadiness on the sediment transport in a braided river. This is possible only by following a statistical approach based on multiple repetitions of the same flow hydrograph. Results revealed that for confined network an hysteresis of the bedload response occurs, which leads to higher sediment transport during increasing flow, whereas relatively unconfined networks always show quasi-equilibrium transport rates.
4) A second set of laboratory experiments provided information on the morphodynamics of a braided network subject to variations of the sediment supply. We proposed a simple diffusive model to quantify the evolution of the one-dimensional bed elevation profile. Such simple approach, albeit having a limited range of practical applications, represents the first attempt to quantify this process and enables to study the relevant temporal and spatial scales of the phenomenon. 5) We solved analytically the two-dimensional morphodynamic model for a gravel-bed river bifurcation. This furnishes a rigorous proof to the idea proposed by Bertoldi and Tubino (2007) to interpret the morphological response of bifurcation in light of the theory of the morphodynamic influence. The analytical approach enables to investigate the fundamental mechanics which leads to balance, and unbalance, configurations and, from a more practical point of view, allows for a better prediction of the instability point than the existing 1D models (e.g. Bolla Pittaluga et al., 2003)
Tunnelling and Unruh-DeWitt methods in curved spacetimes
No full textThe analysis and the results contained in this work are rooted in a first contact between the quantum theory and the general theory of relativity. By first contact it is meant that we are not considering candidates for “unified theories", but rather we focus on aspects of the full quantum theory in changing geometric backgrounds: the analysis of such an interaction already had important applications in cosmology, e.g. in the description of the evolution of fields in inflationary scenarios. Another compelling – and still growing – area of application is the study of thermodynamical properties of gravitional systems, which covers the main bulk of this thesis
Mechanisms of Flash Sintering in Cubic Zirconia
No full textThe recently discovered flash sintering technique has shown that the application of a sufficiently large dc electric field (E-field) to a ceramic during sintering can cause sintering at temperatures several hundred degrees below conventional temperatures with sintering rates that allow for sintering in seconds rather than hours. This technique has already been demonstrated in wide range of ceramic materials including ionic conductors, electronic conductors, semi-conductors and insulators. The application of this techniques to a large range of materials and the dramatic lowering of sintering temperatures and times means this technique has the possibility to revolutionize the ceramics field.
Because the field of flash sintering is still young, the dominant mechanisms are still yet to be identified. So far, the mechanisms active during flash sintering remain only hypothetical. The key to the mechanism is that it must connect two phenomena controlled by different species: conductivity, which is determined by the fast moving species, and sintering, which is controlled by the slowest moving species. At this point the primary hypothesis is that the high E-fields used cause the nucleation and separation of Frenkel defects allowing for both high sintering rates and high conductivities.
This work aims to identify the mechanisms involved in the flash sintering of cubic 8 mol% yttria stabilized zirconia (8YSZ). This materials has been selected because it was one of the first materials show flash sintering properties, and that it has been very well characterized because of its use as a fast oxygen ion conductor.
This work began with the construction and initial testing of flash sintering equipment. Mechanistic investigations were performed on fully dense presintered samples of various grain sizes and single crystalline samples subject to the voltages similar to those used during flash sintering at constant temperatures between 600°C and 1000°C. Because flash sintering has a sintering component and electrochemical component, dense samples were used to remove the sintering so observations can be made only on the electrochemical behaviors during these electrical treatments. Additionally, the range of E-fields used for flash sintering of green 8YSZ samples was increased by an order of magnitude from the 150 V/cm to 2250 V/cm.
Treatment of fully dense and single crystal samples show that the electrolytic reduction of ZrO2 to ZrO2-δ give I-V relations and power dissipations that are similar to those observed in flash sintering of powder samples. Flash sintering using E-field up to 2250 V/cm reveals several relationships between temperature, E-field, current density and power dissipation and their relation to the onset of sintering and densification. Most importantly the onset of sintering can be determined by the power relationship TOnset = 2440 E-1/5.85, where TOnset is the furnace temperature when flash sintering starts in K and E the applied E-field.
Based on these observations, a new mechanism based on electrolytic reduction in the material is proposed to explain the onset and early stages of flash sintering and the observed electrical behaviors. Based on this, the movement of reduced zirconia in the E-field is proposed as a possible sintering mechanism
The policisation of EU Energy Policy: Instances of Instrumental Re-framing by the European Commission
No full textOver the last fifteen years, the energy policy of the European Union (EU) has changed significantly. It has become more cooperative and integrated across the borders of EU Member States and less preoccupied with the state-centred discourse of energy-supply security. The European Commission, in particular, has policised EU energy policy by re-framing it as a complex patchwork of many energy-related policy interventions. This shift took place in the aftermath of several critical events that affected Europe’s energy supply and jeopardised its energy security. Energy policisation occurred, in other words, when it was reasonable for EU Member States to securitise rather than integrate their energy policies. The core research question of this thesis addresses this apparent paradox: to what extent has EU energy policy become more integrated, and why has this change occurred when it was least expected?
This study argues that the shift towards energy policisation has been discursive. The European Commission has been able to harness unprecedented windows of opportunity created by recent crises to re-frame energy policy according to its overarching understanding of EU integration and public policy-making. The Commission has promoted—for over forty years—a vision of energy policy that spans energy security, market competitiveness, environmental sustainability, and energy efficiency. Based on a bibliometric test, this thesis identifies the type of discursive ‘vehicles’ used by the Commission to diffuse its policy ideas and create consensus about its policy agenda.
This thesis also argues that the Commission has been able to use diverse discursive tactics to challenge the prevailing energy policy narrative of the Member States and drive the policy-making process towards more integration. The two case studies analyse two instances of instrumental energy policisation. The case of the wind-power offshore grid projects developed in the North Sea during the last decade shows how the Commission managed to socialise other energy policy stakeholders into its own policy agenda and urge national governments to adopt a more integrated perspective on the issue at stake. The case of the Energy Efficiency Directive negotiations, ended successfully in late 2012, shows that the Commission has also been able to challenge the governments’ state-centred discourse more ‘frontally’. The Commission re-told the story of EU-wide energy cooperation as being so necessary as to force Member States to back away from their resolve, approve the Directive, and accept the binding constraints it contains.
Ultimately, this thesis tells a story of continuity and change in EU energy policy. There has been continuity in the decades-long Commission’s advocacy for a more complex and integrated EU energy policy and in its guiding belief that public policy in Europe is, under all circumstances, best made at the EU rather than at the national level. There has been change in the sudden and unpredictable effect that crisis and shocks have had on the preferences of policy actors. By telling a story of variation in EU energy policy and successful discursive re-framing by the Commission, this thesis contributes to the on-going debate on the impact of non-material factors such as ideas, meaning, goals, and visions on the outcomes of policy-making. By combining bibliometric, process-tracing, and discourse analysis techniques, this thesis has sought to provide a more reliable and replicable operationalisation of ideational elements and has expanded the prospective agenda for more cross-policy research in EU studies and public policy analysis
Seismic safety evaluation of industrial piping systems and components under serviceability and ultimate limit state conditions.
No full textAlthough industrial piping systems and their components have been found highly vulnerable under earthquake events, there exists an inadequacy of proper seismic analysis and design rules for these structures. Current seismic design Standards and Codes are found to be over-conservative and some components, e.g., elbows, bolted flange joints and Tee joints, do not have detailed design guidelines that take into account earthquake loading. Thus, a clear need for the development of improved seismic design rules for such systems is evident. In this respect, numerical and experimental studies on piping systems and their components subjected to earthquake loading could be useful. As a result, valuable information, such as seismic capacities and demands under different limit states, could be utilized for the amendment of relevant design Codes and Standards.
This thesis undertook a numerical and experimental investigation on a typical industrial piping system and some of its components in order to assess their seismic performance. In particular, the following issues have been pursued: (i) design of two non-standard Bolted Flange Joints (BFJs) suitable for seismic applications; (ii) experimental testing of the designed BFJs under monotonic and cyclic loading in order to check their leakage, bending and axial capacities; (iii) finite element analysis of a piping system containing several critical components under seismic loading; (iv) implementation of a pseudo-dynamic and real time testing schemes to test the piping system under seismic loading; and (v) pseudo-dynamic and real time tests on the piping system under several levels of earthquake loading corresponding to both serviceability and ultimate limit states.
The above-mentioned activities were attained in this thesis. In particular, two different non-standard BFJs, comparatively thinner than the Standard ones, were designed, and their performance was examined through a number of monotonic and cyclic tests. Experimental results exhibited a favourable performance of the BFJs under bending and axial loading and moderate internal pressure; a good capacity in terms of strength, ductility, energy dissipation and leakage was observed. Performance of a typical full-scale industrial piping system containing several critical components, such as elbows, a bolted flange joint and a Tee joint, under realistic seismic loading was investigated through extensive numerical and experimental activities. The techniques of pseudo-dynamic and real time testing with dynamic substructuring –hybrid testing- were adopted to carry out experimental activities on the piping system under several limit state earthquake loading suggested by performance-based earthquake Standards. Implementations of hybrid tests were challenging mainly because the piping system was endowed with distributed masses and subjected to distributed earthquake forces, for which these experimental techniques have been considered inadequate so far. A number of mode synthesis techniques, namely the Craig-Bampton and SEREP methods, were discussed and their effectiveness was analysed for the realization of these tests. A characterization of the actuators to be used in the experimental tests was performed based on a transfer function. Relevant hybrid tests were successfully executed and they displayed a favourable performance of the piping system and its components; they remained below yield limits without any leakage even for the collapse limit state
Studies in Classical Behavioural Economics
No full textThis thesis distinguishes Classical Behavioural Economics (CBE) from Modern Behavioural Economics (MBE) and discusses Herbert Simon's pioneering contributions to CBE in detail. CBE emphasises the role of bounded rationality, satisficing and heuristics (procedures) in human decision making in contrast to optimization, which is widely used in MBE. In the framework of CBE, heuristics are algorithms, which are embedded in the Information Processing Systems (IPS) in Human Problem Solving (HPS) environments. The argument here is that the premise of CBE is highly suitable for algorithmic modelling of adaptive agents facing complex economic environments. It explores the theoretical foundations of bounded rationality and substantiates the difference between satisficing and optimization, and claims that the former is more general than the latter. These investigations are carried out from the perspective of Computability Theory and Computational Complexity Theory, which provide a coherent foundation for Herbert Simon's work on problem solving and for CBE in general. The second part of the thesis explores the game of Go from the perspective of problem solving in CBE. Its generality, suitability and complexity are analysed in detail. A pseudo IPS which is capable of playing Go is also constructed based on the insights from Simon's work on protocol analysis and information from Go documentaries. The claim of this thesis is that Go can be a powerful paradigm to better understand human economic behaviour in diverse and complex environments