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Balancing conflicting rights in the digital age: the case of information privacy vs. copyright enforcement against file sharing
Get PDFThe research, employing a comparative and multidisciplinary approach, aims at understanding the conflict between information privacy and copyright enforcement in the digital era. Throughout the whole study attention will be paid to the effect that technology has on these rights. The systems under scrutiny will be the European one (with particular regard to Italy) and the North American ones (US and Canada).
The starting point of this analysis are a number of selected lawsuits in which copyright holders have tried to enforce their rights against Internet users suspected of illegal peer-to-peer downloading. In so doing, copyright enforcement collided with users’ information privacy. In analyzing the way in which these decisions were taken, I shall try to understand how technology affects society. Many studies have demonstrated the interaction between technology and society. Copyright and information privacy laws are themselves a product of technology and innovation. The idea behind my analysis is that technology not only affects society, but that it also affects lawmakers, and even judges (who, directly or indirectly, are lawmakers as well). Indeed, judges do not live a secluded life, but operate within a society. Therefore, it is at least plausible, if not necessary, that their decisions reflect the values of that society. In other words, technology influences society, which, in turn, affects judicial opinion.
To assess if my statement is sound, I shall consider the perception of copyright, limited to file-sharing activities, in the three normative systems. The same analysis will be undertaken with regard to information privacy. As will be seen, unsurprisingly, technology has affected in many ways the substance of both privacy and copyright norms. But technology has also affected people’s lives, people’s way of behaving, and, in the end, people’s minds. This has led to a different perception of the need to protect the aforementioned rights, even if in opposite directions. Privacy concerns have been increasing, while copyright is more and more seen as something “negative”, for a variety of reasons. Given this, a plausible answer to my main line of inquiry is that courts’ decisions reflect this common sense position of prioritizing privacy over copyright.
In particular, I shall examine the literature related to the way courts judge and if and how they can be influenced by the society and culture in which they operate.
Importance will be given to the way that this influence could enter into judicial reasoning. If it is true that technology changes society, which in turn affects the judicial mind, then technology enters into this contextual backdrop for adjudication.
Therefore, the question I would like to answer is the following: could this be a reason why, despite similar legal frameworks, the outcomes of lawsuits are quite different among the considered legal systems? This would be the goal of my research, conscious of the fact that anyway my answer would be just one of the many possible explanations
Spark Plasma Sintering of Titanium and Cobalt Alloys For Biomedical Applications
Get PDFThis work was carried out in the frame of an industrial research project in cooperation with the Eurocoating SpA and K4Sint Srl, aiming at developing the commercial pure titanium, the Ti-6Al-4V and the Co-28Cr-6Mo alloys by Spark Plasma Sintering (SPS) for biomedical application. The definition of the process parameters for the production of a highly porous (cp-Ti), full density materials (Ti-6Al-4V and Co-28Cr-6Mo), and their combination in a surface functionalized full density substrate was the central focus. The SPS parameters were optimized to obtain the Co-28Cr-6Mo alloy in full density state for matching the international standards. Tensile and fatigue were the main properties under investigation. In the case of Ti-6Al-4V alloy the best SPS parameters was defined in a previous work by means of densification curve and tensile properties. Therefore, the fatigue resistance was the main property under investigation. The optimization of the sintering parameters was evaluated by the interdependence between the density, microstructure and hardness. Co-sintering of the cp-Ti with the Co alloy and the cp-Ti with the Ti alloy was carried in order to obtain a porous coated full density substrate in one single step. The SPS parameters were optimized in order to achieve a coating like structure containing macropores with specific range of size and highly interconnected. To that, the space holder technique was chosen since it allows a very good control of the pores characteristics. The interactions at the interfaces were characterized and the best SPS strategy was defined. Subsequently, fatigue tests were carried out in order to assess the influence of the porous coating on the fatigue resistance of the full density substrates. As a general conclusion it may be assessed that the process parameters for the production of the investigated biomaterials have been defined and the microstructural characteristics, as well as mechanical, corrosion properties and wear resistance satisfy the requirements on the international standards. These results have been used to produce implants which are under test
Urban scale phenomena and boundary layer processes in mountain valleys
No full textThe urban climate of the city of Trento, adopted as a representative case study of urban weather and climate phenomena in a mid-sized city lying in a mountain valley, is investigated using different methods and on different spatial scales.
First the intensity of the Urban Heat Island (UHI) is analyzed evaluating the differences between air temperatures measured at an urban automated weather station on a tower, over mean rooftop level, and at five suburban/rural weather stations, located few kilometers around the city boundaries. It is found that the extra-urban weather stations, being affected by different local-scale climatic conditions, display different temperature contrasts compared to the urban site. However the diurnal cycle of the UHI is characterized by similar behaviors at all the extra-urban weather stations: the UHI intensity is stronger at night, while during the central hours of the day an “urban cool island” is likely to occur. The diurnal maximum UHI intensity turns out to be typically of order 3°C, but under particularly favorable conditions it may be higher than 6°C. Wind speed and cloud cover are the weather factors which most affect UHI intensity, making it weaker with stronger winds and cloudier skies.
The investigation of the urban climate of Trento focuses then on a smaller spatial scale, analyzing in detail the thermal field inside an urban canyon located in the city center, by means of two experimental campaigns and the use of a simple model. This simple model simulates the energy balance of the different surfaces composing the urban canyon, calculating both surface and air temperatures inside the canopy. During the two field measurements, carried out in the summer 2007 and in the winter 2008- 2009, temperature sensors were placed at various levels near the walls flanking the canyon and on a traffic light in the center of the street. It is found that the air temperature near the walls, both in summer and in winter, is strongly influenced by direct solar radiation, thus inducing a quite strong imbalance within the canyon: during sunny days an overheating of the east-facing sensors is found in the morning, while in the afternoon west-facing sensors are the warmest. On the other hand, when solar radiation is weak or absent, the temperature field inside the canyon is homogeneous. Moreover air temperature inside the canyon is generally higher than above roof level, the differences being larger during summertime, when solar radiation is stronger and can penetrate for longer inside the street. The measurements performed during the field campaigns, along with observations of wall surface temperatures taken from the literature, allow to validate the results of the urban canyon model. A good agreement between experimental measurements and numerical results is found for both surface and air temperatures, in different seasons and under different weather conditions.
The urban area of Trento, being located in the Alpine Adige Valley, interacts with the atmospheric phenomena typical of these contexts, in particular thermally driven local circulation systems. Moreover the city is located at a point where various narrow tributary valleys or gullies join the Adige Valley, and, as a consequence, complex interactions of local circulation systems are present in the area of Trento. In order to study these phenomena, first the main features of local circulation systems developing in the Adige, Sarca and Lakes valleys, which directly influence the climate of the city, are investigated by means of the analysis of a dataset from surface weather stations covering the period 2004-2011. After that, high-resolution (500 m) numerical simulations with the mesoscale meteorological WRF model, coupled with the multilayer Building Environment Parameterization (BEP) scheme, are utilized to study the urban climate of Trento in the Adige Valley context. Suitable datasets of land use, urban morphology and anthropogenic heat flux have been specifically prepared for these numerical simulations.
Both methods highlight the substantial differences occurring between the local circulation system developing in the Adige Valley, and that blowing in the Sarca and Lakes valleys. The former is a typical valley wind, while the latter is a combination of a lake breeze and a valley wind. The along-valley wind developing in the Adige Valley is mainly determined by the local geometry of the valley, which controls the penetration of solar radiation and the heating of the valley slopes. The lake breeze, the so-called Ora del Garda, starts to blow from the shores of Lake Garda in the morning and then propagates with its cooler air towards north in the Sarca and Lakes valleys, outbreaking into the Adige Valley north of Trento in the first part of the afternoon. In some days the lake breeze is even able to reach the central part of the urban area of Trento, thus lowering the temperature in the city in hot summer afternoons.
Focusing on the urban effects, the model is able to simulate correctly the daily cycle of the UHI, with high intensities during the night and negligible values in the central part of the day. Numerical results suggest that at night the temperature sharply increases at the city boundaries, while the thermal field is quite homogeneous inside the urban area, with only slightly higher temperatures where the urban morphology is more compact. Finally it is found that the presence of the city influences considerably also the wind field, due to the high roughness of the urban area
The Dimension of Cities Revisited: Urbanization Processes and Performing Urban Structures
Get PDFIn this research we analyze the main drivers of the growth of cities, according to their sizes: Mega, Big, Midsize, etc., applying a cross-country analysis that involves about 114 countries in a period of time of forty years (1960-2000). We look for differences in the underlying factors of cities growth particularly among large agglomerations, which are attracting great interest among policy makers. Secondly, we have tried to verify if the growth of cities is linked to urbanization processes that encompass economic structural transformations (performing urbanism), or if their growth is linked to dynamics that disadvantage further economic development (non-performing urbanism). Once considered the relation between the evolution of cities sizes and the shape of the urban structure (using the Zipf’s parameter and other urban variables) we analyze the quality of this structure as a “new” deep determinant of economic growth. This is why, in the last part of the research, we look for possible relations between the quality of the urban structure and economic growth. Our results indicate that growth in very large agglomeration tends to be “non-performing” and that the urban structure which fits better with economic growth is characterized by high urbanization rates but low hierarchical structures
La scelta di un confine: la creazione del dipartimento dell'Alto Adige
No full textLa creazione e l'annessione del dipartimento dell'Alto Adige al Regno d'Italia napoleonico nel 1810 appare interessante sotto molteplici punti di vista. Essa non è mai stata studiata in maniera analitica ed esauriente né dagli storici locali, né dagli specialisti dell'età napoleonica, anche a causa dell'indisponibilità, o della mancata individuazione delle fonti d'archivio. L'individuazione dei fondi documentari della commissione confinaria incaricata della determinazione del confine, assieme alla documentazione concernente l'organizzazione politico-giudiziaria della nuova circoscrizione, ha permesso di disporre di un complesso di carte davvero rilevante e parzialmente inedito attraverso cui fare luce su questo importante tassello di storia del Regno. Altro fattore positivo è stato la conservazione delle carte della commissione di demarcazione all'interno dei fondi del ministero degli Esteri dell'Archivio di Stato di Milano, parte nella sezione Marescalchi, parte nella sezione Testi. Il nucleo documentario e la sedimentazione originaria sono rimasti grazie a ciò pressoché intatti, senza essere manomessi dai riordinamenti peroniani subiti dagli altri archivi negli anni successivi. Per quel che riguarda invece gli atti sulla distrettuazione interna del nuovo dipartimento, essi sono racchiusi in una busta della sezione Censo, e dunque sono costituiti da elementi di provenienza diversa e non sempre concatenati fra loro. A questo inconveniente però è stato possibile porre rimedio grazie alle carte della commissione amministrativa provvisoria retta da Sigismondo Moll, conservate alla Biblioteca Civica di Rovereto. Tale organo, istituito dal generale francese Honoré Vial all'indomani dell'occupazione del Tirolo meridionale nel dicembre del 1809, ebbe il non semplice compito di ripristinare la normale amministrazione civile, finanziaria e giudiziaria nel territorio trentino-tirolese in attesa che gli incontri diplomatici tra Napoleone e l'Imperatore d'Austria chiarissero quale fosse il futuro di questo lembo di terra. Dopo che il 28 febbraio 1810 venne stipulato il trattato di Parigi tra Francia e Baviera, il quale stabiliva la sorte del Tirolo meridionale e la costituzione di una commissione confinaria mista per lo scelta del confine, la commissione Moll fu impegnata non solo nei suoi compiti istituzionali, ma collaborò attivamente sia con i commissari preposti allo stabilimento dei confini, sia con il commissario in missione incaricato dell'introduzione e dell'attivazione del sistema burocratico italico all'interno del nuovo dipartimento. L'incrocio delle fonti documentarie roveretane e milanesi ha permesso di effettuare una ricostruzione dei fatti coerente e coordinata, consentendo di gettare luce sui meccanismi decisionali che portarono alla nascita del nuovo dipartimento
Instability of Dielectric Elastomer Actuators
No full textDielectric elastomers (DEs) are an important class of materials, currently employed in the design and realization of electrically-driven, highly deformable actuators and devices, which find application in several fields of technology and engineering, including aerospace, biomedical and mechanical engineering. Subject to a voltage, a membrane of a soft dielectric elastomer coated by compliant electrodes reduces its thickness and expands its area, possibly deforming in-plane well beyond 100%: this principle is exploited to conceive transducers for a broad range of applications, including soft robots, adaptive optics, Braille displays and energy harvesters. Soft dielectrics undergo finite strains, and their modelling requires a formulation based on the Mechanics of Solids at large deformations. A major problem that limits the widespread diffusion of such devices in everyday technology is the high voltage required to activate large strains, because of the low dielectric permittivity of typical materials (acrylic elastomers or silicones), in the order of few unities, which governs the electromechanical coupling.
Composite materials (reinforcing a soft matrix with stiff and high-permittivity particles) provide a way to overcome these limitations, as suggested by some experiments. In addition, composites can display failure modes and instabilities not displayed by homogeneous specimens that must be thoroughly investigated. Commonly, instability phenomena are seen as a serious drawback, that should be predicted and avoided. However, in some cases they can be used to activate snap-through actuation, as in the case of buckling-like or highly-deformable balloon-like actuators.
Soft dielectric elastomers display electrostrictive properties (permittivity depending on the deformation) and we show how to take into account such a phenomenon within the theory of electroelasticity. Original results regard the investigation of diffuse modes (buckling like instabilities etc.), surface mode instabilities and localized modes. New (analytical) solutions for band-localization instability are provided and then it has been investigated how such instabilities are related to electrostriction. Regarding DE composites, the goal is to evaluate in detail the behaviour of two-phase rank-1 laminates in terms of different types of actuation, geometric and mechanical properties of phases, applied boundary conditions, and instabilities phenomena, in order to establish precise ranges in which the performance enhancement is effective with respect to the homogeneous counterpart
Etnoarcheologia dei Paesaggi Pastorali nelle Alpi: Strategie Insediative Stagionali d'Alta Quota in Trentino
No full textThis research deals with the study of current pastoral seasonal settlement patterns in the uplands of Val di Fiemme (Trentino province), in order to create a quantitative locational model for predicting archaeological pastoral site locations. In fact, few archaeological sites related to pastoral economy are known in the Alps, and this lack of data affects the interpretation of the ancient pastoral strategies. A predictive model could be useful to identify new sites and to optimize archaeological surveys in mountain environments. However, inductive predictive modelling is considered a field with many unresolved theoretical problems. Ethnoarchaeology of pastoralism seems to be a good method to provide a behavioural framework for predictive modelling, and the interaction with quantitative approaches may be worthwhile to improve the ethnoarchaeological methods and theory as well.
The ethnoarcheological research is divided into two parts: a “desk ethnoarchaeology”, the spatial analysis of the relationship between current pastoral/dairying sites (malghe) and mountain environment of Val di Fiemme, in order to create an inductive predictive model; and a “field ethnoarchaeology”, the study of the relationship between modern shepherds/dairymen and environment, in order to understand their locational strategies. The interaction between the first and the second part has enabled the interpretation of the settlement pattern of modern malghe in Val di Fiemme. It has hence been assumed that the model can predict the location of modern and ancient dairying sites, as the malghe are mainly related to milking, milk-processing and cheese storing activities.
The final step has been the archaeological evaluation. The predictive model doesn’t predict the location of Mesolithic hunting sites in the uplands of Val di Fiemme. It predicts instead the location of some dry-stone enclosures in the upland valleys of Ortisé (Mezzana, Val di Sole, TN), while it doesn’t predict the location of rock-shelters in the same area. It has therefore been assumed that enclosures were linked to dairying economy and rock-shelters to simple (“dry”) pastoralism. Further qualitative tests of the model have been carried out in different areas of the Alpine arc.
These results allow two different application of the model: a “predictive” application, aimed at finding new pastoral sites in the uplands, and an “interpretative” application, aimed at discriminating hunting sites and simple pastoral sites from dairying sites. Furthermore, this model has suggested that the interaction between predictive modelling and ethnoarchaeology is useful to tackle the theoretical and methodological problems of these fields of research
Numerical modelling of gravel-bed river morphodynamics
No full textThis thesis is about the development and testing of a novel two-dimensional numerical model (the GIAMT2D model) able to address the hydro-morphodynamic evolution of gravel-bed rivers. The model solves the two-dimensional hyperbolic system of partial differential equations (PDEs) arising from the shallow water-Exner model, describing free surface shallow flows over erodible bed, with suitable closure relations for bedload transport. A coupled formulation of the mathematical problem, which is needed in order to correctly handle sediment transport in Froude trans-critical
flow conditions, is implemented, resulting in a non-conservative hyperbolic problem, which requires the adoption of a path-conservative scheme.
A drawback of the fully-coupled shallow water-Exner model is that in general the solution of the Riemann problem is not easily available, at least if complex empirical sediment transport formulae are applied, which makes the upwind approach inadequate for designing numerical approximations to the solutions. Adoption of the more general, Riemann solver-free centred approach is thus required, the drawback being that centred schemes are significantly less accurate than upwind schemes in some specific cases, namely for intermediate waves and computations at low CFL number. In GIAMT2D an original centred upwind-biased scheme (UPRICE2-C delta) is applied, recovering accuracy typical of upwind methods, still being able to include any bedload transport formula. The proposed scheme results from original studies in applied mathematics, presented in the first part of the thesis, concerning the development of upwind-biased variations of the centred FORCE scheme for the solution of hyperbolic systems of PDEs, in conservative and non-conservative form. The performance of these schemes is thoroughly assessed in a suite of tests for the shallow water equations.
The GIAMT2D model embeds the UPRICE2-Cd scheme extended to second-order accuracy in the ADER framework, inserted in a robust second-order preserving splitting technique for the treatment of frictional source terms, and includes an original wetting-and-drying procedure. The model performance is checked in well-established classical test cases with fixed and movable bed. These applications highlight the capability of the model in correctly and accurately solving the equations in various cases, e.g. in computations at low local CFL number, in the solution of wet-dry fronts with fixed and movable bed and in the prediction of sediment transport in Froude trans-critical conditions.
The concept of "morphodynamic benchmark" is introduced for the purpose of assessing the model performance in reproducing basic river morphodynamic processes for which established theoretical and experimental knowledge is available. Unit processes with utmost importance for gravel-bed river morphodynamics, like free and forced bar instability and the stability of channel bifurcations, are chosen for this aim. In this novel approach for assessing the model capabilities, the numerical solutions satisfactorily compare with approximate analytical morphodynamic solution and laboratory data.
Having proved that the model is able to reproduce the salient features of these classical morphodynamic solutions, an original morphodynamic study is finally carried out, concerning the non-linear interaction of free and forced bars in straight channels, for which a mature analytical theory is not available at present. The numerical runs of GIAMT2D are used to validate the research
hypotheses developed on the basis of existing analytical theories and satisfactorily compare with field observations
Control and Time Integration Algorithms for Real-Time Hybrid Simulation
Get PDFSeismic testing methodologies play a significant role in earthquake engineering due to complexities of engineering materials and ground motion. Among available testing methods, hybrid simulation is more appealing for its merits, e.g., evaluating dynamic responses of large scale structures at lower cost. As a novel member of hybrid simulation, Real-time Hybrid Simulations (RHS), since its conception in 1992, has shown its unique properties and capacity for testing complex structural components, especially rate-dependent ones.
RHS often partitions the emulated structure into portions, which are then either numerically or physically simulated in real-time according to our knowledge of them. In particular, the critical nonlinear and/or rate-dependent parts are often physically modelled within a realistic real-time test, while the remainder parts are simultaneously evaluated by solving differential equations. Evidently, the challenge of these methods is to enforce the coupling at the interface between portions via real-time loading and real-time computation.
Heretofore great development of RHS has been attained. This dissertation is devoted
to developing RHS in two aspects, namely transfer system control and time integration algorithms. In detail, research work and findings are summarized as follows:
The dissertation initially focuses on the implementation of a model-based control strategy –internal model control (IMC) and its comparison with the classic PID/PI control on the lately conceived high performance test system - the TT1 test system. The control strategy of the electromagnetic actuators consists of three loops, namely one speed loop and two displacement loops. The outer displacement loop is regulated with IMC or PID/PI whilst the inner two loops with proportional control. In order to compare different control strategies, realistic tests with swept sinusoidal waves and numerical simulations concentrating on robustness were carried out. Analysis showed that IMC is preferable for its robustness and its ease of implementation and online tuning. Both IMC and PID work similarly and well on the actuator which can be simplified into a first-order system plus dead time. In addition, RHS was performed and showed the favorable state of the system.
In order to accurately compensate for a time-varying delay in RHS, online delay estimation methods were proposed and discussed based on a simplified actuator model. The model, consisting of a static gain and dead time, results in nonlinear relationships among different displacements. The estimation based on the Taylor series expansion was further developed by introducing the recursive least square algorithm with a forgetting factor. Then this scheme was investigated and assessed in pure simulations and RHS via comparison with two other methods. Finally, the proposed scheme was identified to be satisfactory in terms of its convergence speed, accuracy and repeatability and to be superior to other methods.
With the insight into the weakness of available compensation schemes in mind, two polynomial delay compensation formulae considering the latest displacement and velocity targets were proposed. Assessment and comparisons of the formulae by means of frequency response functions and stability analysis were carried out. In order to facilitate delay compensation, another novel compensation scheme characterized by overcompensation and optimal feedback was conceived. Numerical simulations and realistic RHS were performed to examine the proposed schemes. The analysis revealed that the proposed polynomial formulae exhibit smaller prediction errors and the second-order scheme with the LSRT2 algorithm is endowed with a somewhat larger stability range. Moreover, the overcompensation scheme was concluded to have the ability of time-varying delay accommodation, error reduction and sometimes stability improvement.
With regard to time integration algorithms, this dissertation extends the equivalent force control (EFC) method which is a method of RHS with implicit integrators to RHS on split mass systems. The EFC method for this problem was spectrally analyzed and was found more satisfactory stability than some explicit integrator. Then larger control errors due to quadartically interpolated EF commands were recognized and treated with a proposed displacement correction. In view of the inherent feature of RHS –multiple quantities coupling at the interface, the correction was extended to simultaneously update displacement and acceleration. Spectral stability analysis and numerical simulations demonstrated that: (1) the correction can remove the constraint of zero-stability to the method and reduce algorithmic dissipation; (2) it also works well for MDOF systems.
Finally, an inter-field parallel algorithm for RHS, namely IPLSRT2, was developed and analyzed. This method was based on the Rosenbrock (LSRT2) method and a prior inter-field parallel integrator–PLSRT2. The LSRT2 with different stage sizes, velocity projection and modified Jacobian evaluation were introduced to the algorithm in order to avoid and/or weaken the disadvantages of the PLSRT2 method, such as inefficient computation, displacement and velocity drifts, and complicated starting procedure. Accuracy analysis, spectral stability analysis, pure numerical simulations and realistic RHS were performed to investigate the properties of the IPLSRT2 method. Compared with the PLSRT2 method, this method exhibits pros and cons. In detail, the method loses the accuracy order due to the velocity projection applied at all time steps. However, it can provide more accurate displacement and velocity results in common applications where a little larger time step is required. In some cases, the proposed method exhibits smaller phase shifts and dissipation. Moreover, computation efficiency in Subdomain A is improved and its implementation in real-time applications is simplified
Motor Resonance meets Motor Performance: Neurocognitive investigations with transcranial magnetic stimulation
No full textThe classical mirror neuron theory of action understanding asserts that when we observe an action, the representations that are engaged for performing it, are automatically activated.
In order to do gain information about the role of the simulation in action understanding a state dependent TMS experiment has been carried out. The fundamental idea is to adapt a neural population in the motor system and then testing the effects of this adaptation when participants categorize visually presented actions.
The second aim of the present work is to find a paradigm, or a particular cognitive set, that does not allow the simulation process to take place when the participants are observing actions. This step will be important in testing whether the simulation process is necessary in order to understand a visually presented action