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Ricerche su Astidamante il Giovane
Full text linkIl presente lavoro si propone come una ricerca sulle testimonianze e i frammenti relativi all’opera di Astidamante il Giovane, poeta tragico ateniese del IV secolo a.C.: un drammaturgo di grande successo, discendente diretto del grande Eschilo e quindi esponente di una delle più importanti theatrical families di Atene. Il progetto di tesi è nato dalla considerazione che, pur nel generale revival d’interesse che ha caratterizzato negli ultimi decenni gli studi sul teatro greco del IV secolo, ancora molto restava da fare per ricostruire le opere e i profili dei singoli drammaturghi. È un lavoro naturalmente molto difficile e arduo, considerata la frammentarietà e la scarsità dei testi superstiti e, a volte, la contraddittorietà delle testimonianze relative ai singoli poeti. Ma è comunque un lavoro che appare opportuno, se non necessario.
Citato da Aristotele per l’originalità delle sue trame ed elogiato da Plutarco, Astidamante è un protagonista assoluto della scena teatrale del IV secolo. La ricostruzione della sua vicenda biografica e della sua carriera teatrale è tuttavia per molti versi sfuggente: il primo problema è costituito dalla citazione nelle testimonianze antiche di due Astidamante che, in un modo non sempre chiaro e coerente, vengono distinti come padre e figlio. E’ stato necessario dunque riesaminare nel dettaglio le testimonianze antiche relative ai due Astidamante, affrontando i diversi problemi relativi alla cronologia e alla carriera teatrale dei due poeti. E si è cercato anche di addurre ulteriori elementi a favore dell’ipotesi che la tradizione antica sia sostanzialmente attendibile e che siano effettivamente esistiti due poeti omonimi, padre e figlio, di nome Astidamante. Si è quindi proceduto a un’analisi di tutte le testimonianze biografiche. Particolare attenzione è stata riservata agli aneddoti relativi alla dedica di una statua ad Astidamante nel teatro di Dioniso e all’epigramma autocelebrativo che, secondo la tradizione, il poeta avrebbe voluto incidere sul basamento della statua. Aneddoti che si collegano a una tradizione paremiografica di cui si sostiene la derivazione da un verso attribuito a Filemone Comico (Phil. Fr. 160 K. – A. = Fr. 190 K.).
Si è proceduto quindi a un’analisi dei frammenti delle singole opere, cercando di valorizzare la bibliografia più recente e di affrontare una serie di problemi di dettaglio, suggerendo anche, nei limiti del possibile e del ragionevole, una ricostruzione della trama delle singole opere e cercando di mettere in luce gli elementi sia di continuità sia di discontinuità tra i trattamenti del mito nell’opera teatrale di Astidamante e la tradizione drammatica del V secolo.
Ho ritenuto opportuno corredare la tesi con una serie di tabelle che cercano di fornire un quadro schematico e di elaborare in forma statistica i testimonia dei frammenti drammatici del IV secolo, con lo scopo principale di valutare il carattere dei testimonia che riportano i frammenti di Astidamante nel contesto complessivo della tradizione indiretta della tragedia del IV secolo.
In appendice, per comodità del lettore, ho raccolto anche tutte le testimonianze e i frammenti con un essenziale apparato critico e la traduzione italiana (a tutt’oggi esisteva solo quella di Mario Untersteiner sulla base del testo critico di A. Nauck)
Architecting Evolving Internet of Things Application
Full text linkThe Internet of Things paradigm has witnessed an unprecedented growth pervading every sector of the societal fabric from homes, cars, health, industry, and business.
Given the technological advances witnessed in all the enabling technologies of IoT, it is now possible to connect an increasing number of devices to the internet. The
data value chain has slowly risen in prominence. Moving from the vertical solutions to a horizontal architecture has resulted in the development of services which is the
culmination of multiple sources of data. The complexity of handling the growing number of connected devices has resulted in active research of architectures and platforms
which enable the service providers and data providers to navigate through the maze of technologies. We also look at the data generated by the real world, which is dynamic and non-stationary in nature. The always connected virtual representations of the devices facilitates applications to proactively perceive, comprehend and adapt to the real world situations. Paving the way to integrate learning algorithms, this thesis presents a modular architecture with elements to detect, respond and adapt to the changing data. Given the scope of IoT in different applications, we explore
the implementation challenges both the advantages and limitations in two different domains. It includes (i) Smart Asset Management Framework: To provide real time
localization of movable medical objects in a hospital. Additionally the movement patterns of the objects in studied and modeled to facilitate predictions. This helps to improve the energy savings of the localization technology. It helps the hospital authorities to understand the usage of the objects for efficient resource planning.
(ii)Transitioning to a Industrial4.0 application: To facilitate in the digital transformation of a solar cell research center. With the similar concepts of virtualization (digital twins) and real world knowledge generation, the digital factory vision is conceptualized and implemented in phases.The supporting work including prototypes for smart home environment control, people activity detection and presence detection using bluetooth beacons leading to the development of the architectural components is presented. The implementation details along with results and observations in each of the sections is presented
Atomic Modelling of Disorder in Metal Nanocrystals
Full text linkThe atomic mean square displacement (MSD, ¯(σ_i^2 ) ) is often used in computational materials science studies to calculate measurable properties from the atomic trajectories of simulations; for example, the diffusion coefficient, which according to Einstein relations (Einstein 1905) on the random walk is 1/6 of the slope of the trend of ¯(σ_i^2 ) vs. time (Chandler 1987). Equally relevant is the mean square relative displacement (MSRD, ¯(σ_ij^2 )), used in X-ray Spectroscopies, mainly EXAFS, to describe the atomic disorder in solids (Calvin 2013) (Fornasini 2014).
Less known is the relevance of the MSRD in X-ray scattering from nanoparticles. In particular, in Total Scattering methods (Pair Distribution Function and Debye Scattering Equation), which rely on an atomistic description of the nanoparticles, the MSRD is the key to distinguish dynamic (thermal) and static disorder (Krivoglaz 1969) (Kuhs 2006). Interestingly, the trend of the MRSD with the distance is characteristic of the nanoparticle shape, an aspect investigated in some detail in this Thesis work. More generally it can be shown that beyond the expected effect of nanocrystal size, the shape alters the contribution of the surface, which is quite relevant for the MSRD. The importance of the shape and of the surface region holds also in case of clusters of nanoparticles, not only in isolated particles. Besides the MSRD, the atomic configurations simulated by molecular dynamics (MD) can also be used to calculate the so-called Warren plot (or diagram), originally introduced in the seminal work of Warren & Averbach of the ‘50s to describe the effects of plastic deformation in metals (Warren B.E. 1950). Recent work has shown how to obtain Warren plots from the analysis of the diffraction line profiles according to the Whole Powder Pattern Modelling (WPPM) (L. M. Scardi P. 2002) (Scardi P 2017) (P. E.-W. Scardi 2018), in particular from the analysis of the strain component of the diffraction peak profile broadening. As proposed in this work, If the Warren plot can be calculated directly from MD simulations, then it is possible to proceed backwards, and construct more reliable strain functions from an atomistic knowledge of the local atomic displacement caused by static and dynamic disorder components. This thesis is divided in two main parts, discussing two different but complementary topics:
atomistic modelling and calculations of displacement quantities,
application of the above results to experimental case studies, based on the modelling of diffraction data from nanocrystalline systems.
We start by describing the atomistic simulations and vibrational properties calculated for several atomic configurations. The main case study concerns Palladium nanoparticles of different sizes and shapes, for which we show that vibrational properties and correlation properties between atoms pairs are greatly influenced by the geometric shape of the nanoparticle and to a lesser extent by their size. The interest is on truncated cubes, i.e. cubes whose edges and corners are progressively removed, as in the series of so-called Wulff solids, ranging from the cubic to the octahedral shape (Wulff G. 1901). As shown in (ii), these are the object of several experimental studies.
The developed methodologies are nevertheless applicable to other cases, like the clusters of nanocrystals observed in powders produced by high-energy ball milling, which is also a topic discussed in (ii).
The work aims to show a general approach to atomistic modelling, both for isolated nanoparticles with definite shapes, and grains of unspecified shape in plastically deformed polycrystalline materials. We then use the values for displacement quantities (e.g., MSD, MSRD) calculated for the simulated systems to compare them to the experimental results. An underlying fact that seems to hold in all the different cases is that the surface behaviour of nanomaterials has the largest influence on the displacement quantities. For isolated particles we observe strong correlation between displacement quantities and the shape; whereas in the case of a nanocrystalline grain clusters (Figure 1 1) we see that no matter the defects inside the grain, the main contribution to MSRD is given by the grain boundary
Learning to merge - language and vision: A deep evaluation of the encoder, the role of the two modalities, the role of the training task.
Full text linkMost human language understanding is grounded in perception. There is thus growing interest in combining information from language and vision. Multiple models based on Neural Networks have been proposed to merge language and vision information. All the models share a common backbone consisting of an encoder which learns to merge the two types of representation to perform a specific task. While some models have seemed extremely successful on those tasks, it remains unclear how the reported results should be interpreted and what those models are actually learning. Our contribution is three-fold. We have proposed (a) a new model of Visually Grounded Dialogue; (b) a diagnostic dataset to evaluate the encoder ability to merge visual and language input; (c) a method to evaluate the quality of the multimodal representation computed by the encoder as general purposed representations. We have proposed and analyzed a cognitive plausible architecture in which dialogue system modules are connected through a common \emph{grounded dialogue state encoder}. Our in-depth analysis of the dialogues shows the importance of going beyond task-success in the evaluation of Visual Dialogues: the dialogues themselves should play a crucial role in such evaluation.
We have proposed a diagnostic dataset, \emph{FOIL} which consists of images associated with incorrect captions that the model has to detect and correct. Finally, we have used FOIL to evaluate the quality of the multimodal representation produced by an encoder trained on different multimodal tasks. We have shown how the training task used effects the stability of the representation, their transferability and the model confidence
Technology Mediated Information Sharing Within the Triad of Aged Care
Full text linkMore than other age group, older adults suffer from multiple chronic conditions, receive care from multiple healthcare providers and settings, and transition across this continuum of care as they age. During the last decade, we have observed the transformation of aged care worldwide both on organisational and legal levels due to an increasing older population from one side and the use of technology in their care from another. In addition, the involvement of family members as informal caregivers introduces the concept of a triad of aged care: a collaboration of senior patients, their relatives and professional caregivers; and poses additional challenges such as appropriate and efficient communication from the points of views of all care stakeholders. Hence, sharing of health and wellbeing information (HWBI) in the care triad becomes particularly important, and e-Health services have shown the potential to support this, for example, by becoming a channel that could mediate sharing, while taking into account the values and concerns of all groups of users.
In this thesis, we explore existing strategies of HWBI sharing in various aged care scenarios and identify the challenges and opportunities of designing information systems that could support them. In particular, by conducting a systematic literature review and a series of user studies with all three groups of care stakeholders, we study if and how technology-based mediation of informational exchange can improve institutionalized care for older adults. We primarily focus on different dimensions of aged care scenarios, based on the involvement of triad stakeholders, the level of acceptance of technology, and the degree of control seniors have over sharing their HWBI. To gather design recommendations for such information systems, we investigate HWBI-related work practices of professional caregivers; information needs of family members, and information disclosure preferences and associated concerns of seniors, including their reasons to share or not to share. We raise a critical discussion on values addressed by e-Health interventions and illustrate the views of care stakeholders, revealing that these views can be conflicting, given their needs and priorities. For instance, tensions emerge between values that prioritize placing the responsibility on a physician for their patients versus a value system that prioritizes patient autonomy.
By discussing information and interaction design of technology-based mediation of HWBI sharing and based on the research findings of this thesis, we provide a set of design principles and requirements targeting the following areas and roles:
- e-Health and HCI researchers, providing a foundation for their future research,
- designers, who could benefit from a complete image of the abilities and needs of potential users in this sensitive and complex care context,
- healthcare and legislation policies, that could adhere to a system of values that place a premium on patient empowerment, and
- educational programs, that need to provide seniors and triad actors with the knowledge of how to share personal health information digitally.
Finally, following a user-centred design approach, we implement these design recommendations and evaluate them with caregivers to validate our findings
The State Again
Full text linkThe overall goal of this work is to study the effect of a crisis on the distribution and employment and the space of manoeuvre of the government for supporting and reverting the negative shock produced by such a crisis. Every chapter of this work and the related models are supported by both a theoretical background analysis and by numerical dynamic simulations. Stylized facts show that the income and wealth inequality in all the OECD countries has been constantly increasing after the 1960s. Piketty has been one of the most important authors that highlighted the rising inequality issue, mainly in the OECD countries. For example, Piketty (2014) shows that the income share held by the top percentile in countries such as US, Canada and UK increased from 8%-10% in the 1960s up to 14%-18% in the current decade. Similar figures are now provided by the World Inequality Lab that has updated data for almost every country up to 2016. At the same time, the wage share for the majority of the OECD countries substantially decreased. For example, countries such as Italy and Spain experienced a decrease in wage share from about 73% in the 1970s to about 63% in the current decade (Hein, 2014). Taking into account such a stylized fact, we will consider a model with two social classes, workers and capitalists. These social classes differ in terms of their initial endowment, their consumption behaviour, the different loans repayment conditions required to them by the banks and in terms of the ways in which they can use their financeable wealth. This is a very important departure hypothesis from the mainstream point of view models that generally consider a population made up of “a representative agent” of the whole society.
Considering the inequality levels that the OECD countries are experiencing, we took the Post-Keynesians school of thought as a very good reference point since it always focused its attention on the relation between the level of employment, the aggregate demand and the distribution between social classes. In line with the post-Keynesians tradition, we believe that a theory cannot be correct unless it starts from realist or realistic hypotheses, although it is recognized that assumptions are always abstractions and simplifications (Lavoie, 2014). Therefore, we developed a step by step model with the analysis of an economy based on some well-known stylized facts. Beyond the social classes distinction, we take into consideration the temporal lag between production and sales of products by firms and the one between income received by the social classes and their expenditure. Those two temporal lags are the very key aspects we focus our attention on in the model presented in Chapter II named “Keynes, Kalecki and Metzler in a Dynamic Distribution Model”. In that chapter, we merge the hints of Keynes and Kalecki about the distribution of social classes and the intervention of the government in supporting the aggregate demand together with Metzler’s hint about the mismatching process between aggregate demand and aggregate production. Metzler’s mismatching process would finally generate inventories of consumption goods. More specifically, it is argued that even if Post-Keynesians models focused their attention on output growth, employment and income distribution relating those issues with a stronger intervention of the state, they all (even the canonical Kaleckian model) overlooked the adjustment - or non-adjustment - dynamics from the ultra-short run to the short run period upon which the short run and long run models are then constructed. In fact, even if the Kaleckian models completely reject the standard neoclassical production function (rejecting diminishing returns and rejecting the substitution between capital and labour) they also very strongly rely on a final equilibrium between aggregate demand and aggregate production. The canonical Kaleckian short run models are constructed upon the consideration of the effective labour demand curve defined as “the locus of combinations between real wages and levels of employment which ensure that all produced goods are sold at the price set by firms” (Lavoie, 2014). As argued by Lavoie (2014), this construction assures that an increase of real wage leads to an increase in the employment level. That has been and still is definitely one of the cornerstones for the Post-Keynesian authors. We argue that the equilibrium assumption between the aggregate demand and the aggregate production plays a key role in obtaining the standard Kaleckian conclusions regarding the relation between effective demand, employment levels and the distribution of surplus product between the social classes. The main question arising from the previous enquiring exercise about adjustment dynamics in the Kaleckian framework is that, because of the overlooking on that adjustment process between aggregate production and aggregate demand, also its conclusions might be consequentially affected. More precisely the main Post-Keynesian Kaleckian conclusions to assess are the following: would it still be true that higher real wages lead to a higher level of employment? Would it still be true that a decrease in the propensity to save will lead to an increase in output and employment? Would it still be true that in order to keep employment from falling, whenever there is an increase in productivity there must be some increase in real wages? And finally, most importantly in terms of policies, would it still be true that in order to keep employment from falling, even when the economy faces a pari passu increase of real wage and productivity level, it would be necessary an increase in real autonomous expenditure such as a strong government one?
In this way, our model analyses under which conditions the standard Kaleckian conclusions are still valid considering a disequilibrium situation. Two scenarios are simulated: one with fixed expectations as in Metzler (1941) and another new one based on adaptive expectations and asymmetric behaviour of the wages-unemployment relation. The model questions the effective demand labour curve and suggests that an increase in real autonomous expenditures, mainly by the Government, might be even more essential than what is generally considered in the Kaleckian literature, to avoid increasing unemployment in an increasing wage world.
The model presented in Chapter III named “The stabilising role of the Government in a Dynamic Distribution Growth Model” builds upon the model presented in Chapter II and considers once again the effect of a crises on the relation between aggregated demand, employment and distribution between social classes adding important characteristics of realism that were absent in the previous chapter. Here, we consider the gestation period of the investments and the presence of the government investigating its margin of manoeuvre in such an economy. The first aspect takes inspiration by Kalecki (1971) himself who considers the three different Investment stages: investment order or Demand (I^D), investment Production (I^P) and investment delivery or Completion (I^C). In line with a post-Kaleckian perspective, we consider the expected profitability and the capacity utilisation as the two main variables as driving forces for the investment decisions. The second new aspect of this model compared to the one presented in Chapter II is the explicit presence of the government. In fact, even if chapter II suggested the Government as the emblematic autonomous figure able to foster expenditure in times of recession, its actual role in the economy was not analysed. Many post-Keynesian scholars have underlined how recent decades have been characterised by a strong downgrading of the fiscal policy role as a stabilisation instrument of macroeconomic policy (Arestis and Sawyer, 2003). In this way, this chapter analyses exactly the space of manoeuvre of the government and the role of the fiscal policies into a “functional finance” framework where the government "can and should be called upon as a key part of the remedy" (Fazzari, 1994) to ensure a high level of economic activity whenever the private sector is unable to do so by itself.
In the light of such a functional finance framework, the government actions should be inspired to achieve a more stable and sustainable growth path. More specifically, we here investigate the possibilities that the Government has to boost and support the economic activity with its two main tools, public investments spending and a taxation system in two scenarios. The first scenario simulates an exogenous fall of private investments while the second one relates to an exogenous increase in labour productivity and real wages. In particular, here we test the canonical Kaleckian model conclusion according to which even when the economy faces a pari passu increase of real wages and productivity level it would be necessary an increase in real autonomous expenditures - such as the one implemented by the government - in order to keep employment from falling.
At the same time, the aim of this chapter is also to explore the role of the Government in stabilising the economy exactly thanks to the previous tools. In fact, Chapter II underlined the possibility of an arising unstable path from a mismatching dynamic between aggregate demand and aggregate production. It was argued that such an unstable path might develop because of “wrong” oversensitive expectations of firms regarding the production of consumption goods. Therefore, chapter III focuses exactly on the space of manoeuvre of the government in stabilizing an unstable economic scenario caused by a crisis.
The model built in Chapter IV named “The distributive monetary analysis of a sustainable ecological economy” is the natural evolution of the models developed in Chapters II and III. In such a model all the previous stylized facts are contained, namely the temporal lag between production and sales of products by firms, the temporal lag between income received by the social classes and their expenditure, the gestation period of the investments and, finally, the intervention of the government. The most important difference with respect to the models presented in the previous chapters is its overall monetary and ecological framework. In fact, for simplification purposes the previous models were assuming that, in line with a horizontalist approach, commercial banks were providing funds on demand to firms for financing their investments. However, the explicit relations among all the sectors of our economy were not fully exposed. In this chapter Graziani’s endogenous money theory is used and we are developing a Post-Keynesian Stock Flow Consistent (SFC) model to track all the economic relations, both the real and monetary ones. At the same time, the use of a SFC model ensures that “there are no black holes - every flow comes from somewhere and goes somewhere” (Godley W. , 1996) through a rigorous accounting framework, which guarantees a correct and comprehensive integration of all the flows and the stocks of an economy.
Such as Kalecki, Graziani and the circuitists economists introduce a preliminary distinction between producers and wage earners. The first step of the monetary circuit is always characterized by firms’ decision to activate production and, in order to do so, they take up loans by commercial banks. In this sense, commercial banks are able to create deposits ex nihilo, granting them loans and, at the same time, creating deposits. In this way, the starting logical cause of the expansion of money is exactly the firms’ willingness of contracting a liability to activate production. In the second step, firms use those loans to pay workers and in this way to obtain the amount of consumption goods desired through the production process. When such funds are transferred by firms to households they instantaneously become income paid for the work provided to firms by workers.
Finally, the last step of the Monetary Circuit is characterized by the households’ spending decision to use the money balances previously obtained as income. In this step, while households use their funds to buy consumption goods, firms obtain back those money balances they initially paid to households for their work.
In this way, the previous Monetary Circuit analysis is not in contrast with the one made by Kalecki upon the way workers obtain their wages and use all of them to buy consumption goods while capitalists are able to spend just a proportion of their income.
Finally, together with its social and monetary framework, our economy is also characterized by an environmental one since we here study the impacts that the economic consumption has in terms of ecological erosion of natural resources. In this way, the model of chapter IV questions the expenditure margins of the Government – in particular after a crisis - and uses the suggestions of the monetary circuit theory to analyse the space for fiscal policies to reduce unemployment boosting the economic activity, to obtain a more equitable distribution between social classes in a sustainable ecological way. Our understanding is that despite many contributions focused on the topics of recovery, distribution and ecological sustainability, few of them tried to tackle them all in a comprehensive way considering the rediscovery of the endogenous money phenomena as one of the most important breakthroughs in the last decades. Here we argue that exactly the endogenous money feature is the essential fil rouge to better understand and connect the three previous important aspects. It is so when we analyse the sectors connections and the policies ones devoted to recovery, and also if we consider how the different incomes and wealth are captured and distributed by the different social classes and finally when we point out the ways of financing long term ecological path to preserve a sustainable environment.
Indeed, our overall work in Chapter II, Chapter III and Chapter IV is a step by step construction of an organic and consistent model. It starts with a more theoretical and simplified approach through Chapter II which investigates the (in)stability conditions of the Kaleckian approach while suggesting the presence of an autonomous figure such as the government one. Chapter III adds more real base features through endogenous investments and government presence while Chapter IV finally concludes considering all the real and monetary links of the sectors into a social and ecological framework
Il reato e il peccato. Il tribunale dell'Inquisizione di Reggio Emilia in età moderna (XVI-XVIII secolo).
Full text linkIl lavoro di ricerca svoltosi in questi tre anni di dottorato (2015 – 2018) è stato incentrato sulla ricostruzione monografica della storia del locale tribunale del Sant’Uffizio di Reggio Emilia e sul suo rapporto con l’episcopio dal punto di vista giudiziario in età moderna. Si tratta di una ricostruzione non semplice, dovuta alla dispersione delle carte. Parole chiave per comprendere come sia stato oggettivamente difficoltoso stilare una “fluida” concatenazione di eventi storici per questa istituzione. Il trasferimento della sede locale, tra Ferrara e Parma (XIII – XVI secolo), tra Parma e Ferrara (1509 – 1564), tra Ferrara e Reggio (1564 – 1598) e infine l’unione con Modena (1780 – 1785) crearono progressivamente un handicap, un vuoto nelle fonti, dovuto alla perdita o al mancato ritrovamento delle stesse, che è stato registrato da vari studiosi quali Prosperi, Spaggiari, Prodi e Biondi, giusto per citarne alcuni. La storia della corte inquisitoriale locale si connette strettamente, almeno nella sua struttura, con la sua storia archivistica: infatti, ad ogni trasferimento della sede, il suo archivio veniva spostato di concerto con essa determinandone la perdita di carteggi. Tale ricostruzione non è stata favorita nemmeno dalla storia dell’Archivio centrale del Sant’Uffizio (oggi Archivio della Congregazione per la Dottrina della Fede) negli anni della Rivoluzione francese e del periodo napoleonico: l’intero patrimonio di carte fu trasferito a Parigi nel 1809 e restituito a Roma nel 1816 a cui seguì la distruzione di gran parte del carteggio per motivazioni logistiche mostrate dagli stessi prelati della Sacra Congregazione.
Fatte queste dovute premesse, tuttavia, non si è rinunciato a stendere una monografia su tale magistratura locale che, nonostante il suo essere spuria e lacunosa in certe parti a causa delle motivazioni addotte prima, senza nulla pretendere cerca di essere la più aggiornata possibile.
Aiutandomi con fonti primarie e cronache custodite all’Archivio Diocesano e di Stato di Reggio Emilia, alla Biblioteca Municipale Antonio Panizzi della stessa città, all’Archivio di Stato di Modena e all’Archivio della Congregazione per la Dottrina della Fede sono giunto alla compilazione di questo studio non tanto secondo un arco cronologico ben scandito ma per macro-tematiche, dividendolo in due parti (comprendenti rispettivamente due capitoli). La prima parte cerca principalmente di descrivere una storia, per così dire, istituzionale della sede locale del Sant’Uffizio dalle origini medievali alla sua unione con la sede modenese e la successiva soppressione. Nel primo e nel secondo capitolo in particolare vengono trattate, rispettivamente, la nascita della corte giudiziaria reggiana sino al suo trasferimento alla capitale estense, Ferrara, e la scansione degli eventi dai suoi anni ferraresi alla soppressione ducale del 1785.
La seconda parte, invece, pone alcuni focus sul bilancio dei procedimenti penali svolti dalla magistratura e sul suo rapporto con il tribunale del vescovo. Il terzo capitolo verte sulla quantità di processi che il tribunale dovette affrontare e su alcuni reati-peccati particolarmente perseguiti tra il XVII ed il XVIII secolo, mentre il quarto capitolo ha come oggetto d’indagine il progressivo cambiamento, tra XVI e XVIII secolo, degli equilibri tra le due personalità di spicco in materia di giustizia di Fede: l’inquisitore da una parte ed il vescovo dall’altra.
Seguono una breve e utile appendice documentaria delle carte più importanti inerenti alcune tematiche sviscerate nello studio e le relative conclusioni.
La ricostruzione di una storia della magistratura che comprendeva un territorio relativamente piccolo come la città di Reggio e le sue propaggini (le vicarìe foranee) fa comprendere non tanto il funzionamento della stessa, quanto l’interconnessione tra centro e periferia, tra la Santa Sede (rappresentata dalla Congregazione del Sant’Uffizio) e la sua sede extra-romana. Un complesso network di provvedimenti e applicazioni degli stessi, di domande e di risoluzioni che nella storia dell’Inquisizione in Italia aggiunge un piccolo pezzo al puzzle enorme di studi sull’argomento
New evidence of functional interactions within the hand motor system
Full text linkHumans developed the ability to use their hands as tools to actively interact with the surrounding world. On a daily basis, without effort or a conscious will to act, we can manipulate dozens of objects placed in the environment to achieve different purposes. This, at first glance simple, ability relies on a network of cerebral areas computing a series of complex neural processes. The core cerebral regions involved in transforming visual inputs into hand actions have been identified within two distinct pareto-frontal networks, the dorsomedial and dorsolateral pathways. These pathways have been traditionally considered to process different types of information independently. The dual-route model of the hand motor system represents a milestone within the literature exploring the neural correlates of motor control. Nevertheless, following the recent improvement of the technical and analytical approaches adopted to investigate brain’s functioning, this initial description has been considered reductive. Nowadays, it is clear that the neural processes needed to produce a hand action require the integration of different information (e.g. spatial location of the object, spatial location of the arm, grip aperture, goal to pursue, etc.) that imply the exchange of information between anatomically distant, but functionally interconnected, cerebral areas.
In light of the most recent neuroscientific advance in the field of motor control, we investigated the specific role of the cerebral areas of the motor system and their functional interactions during the planning and execution of hand actions. In the present thesis, we adopted several methodologies (TMS, fMRI) and analysis approaches (univariate, MVPA, DCM), to explore the involvement of defined areas in specific motor tasks, their representational content and their connectivity profiles.
In the three neuroimaging studies here presented, we first considered the functional dynamics that occur within the hand network (Chapter 2). Secondly, we described a broader and integrated hand motor system including also the ventral stream, always considered as specialized in perceiving visual inputs (Chapter 3). Finally, we focused on the often neglected homologous regions within the right hemisphere (Chapter 4), providing a pan of the hand motor system in its entirety.
The first study (Chapter 2) adopted a combined TMS-fMRI approach, and focused on understanding the interactions between the dorsomedial and dorsolateral pathways of the hand motor system. We adopted a delayed-reach-and-grasp task, performed under different perceptual conditions (eyes opened or closed), and we perturbed the activity of SPOC in the dorsomedial pathway of the left hemisphere by means of rTMS. We used univariate and multivariate analysis to investigate the modifications occurring during the planning phase of the action within areas functionally connected with the region stimulated with TMS. We found that when the normal activity of SPOC is altered, changes in encoding grasping action information occur within the dorsolateral pathway. This study showed a causal interaction between the dorsomedial and dorsolateral pathway of the hand motor network, which are traditionally considered to be specialized and independent.
In the second study (Chapter 3), we adopted fMRI to explore the possible communication between dorsal and ventral stream, verifying the possible complementary and supportive role of the temporal cortex in motor control. To this aim, we adopted a delayed tool-pantomiming task known to recruit the ventral stream. Our delayed pantomiming task allowed us to consider the planning phase of the movement together with the execution of the pantomime. With multivariate analysis, we explored where in the dorsal and in the ventral streams different abstract goals of an action, i.e. independent from the tool identity, are represented in respect to more concrete aspects, related to the tool considered in the pantomime. In addition, we investigated the possible functional interactions between temporal and fronto-parietal regions, showing an exchange of information between the two pathways both with MVPA and connectivity analysis (DCM). Overall, these results point out a hand motor system that not only relies on the specialized-for-action dorsal network, but also on temporal lobe areas.
In the third study of the thesis (Chapter 4), we combined data from Chapter 3 with a complementary fMRI session. In the second session we changed instruction modality and effector used to perform the pantomime, while experimental design and the task requirement were unchanged. This approach allowed focusing on understanding: (i) changes in the encoding of concrete and abstract representation based on task requirements (i.e. different instruction modality and effector) and (ii) the possible encoding of tool pantomimes’ information also outside the classically-defined left-lateralized tool network, in homologous regions within the right hemisphere. Overall, we found task-dependent changes in the representational content of the considered areas both in the left and in the right hemisphere. These results provided novel insights into the neural correlates of tool pantomime, pointing towards the supportive role of the temporal cortices and of the right hemisphere when planning and pantomiming this type of action.
Overall, our studies contributed delineating a novel view on the organization of the hand motor system describing (i) the functional specialization of its different cerebral areas and (ii) the interactions occurring between these regions. Our research highlighted how the hand motor system has a functionally interconnected organization in which, to different degrees, various areas located in three main cerebral routes (ventral stream, dorsolateral and dorsomedial pathways) communicate to build a meaningful motor output
Study of Wear Mechanisms in Braking Systems with HVOF-Coated Discs
No full textThe European Union has undertaken several efforts to reduce the non-exhaust particulate matter emissions from road vehicles. One of the major sources of these emissions is the wear of brake pads and discs. The experimental work presented in this thesis has been performed within the European project called LOWBRASYS that aims at reducing the particulate matter emissions due to the wear of the components of braking systems. Different strategies have been identified for reaching this aim but the present work focuses on the investigation of the wear mechanisms at the disc-pad interface and on their role on the emission in the atmosphere and in the environment of wear debris. In order to achieve the reduction in the particulate matter emissions, the traditional gray cast iron discs have been coated with different cermet coatings deposited via high velocity oxygen fuel (HVOF) process. A further attempt for improving the wear resistance of the gray cast iron discs was performed by applying on them an industrial heat treatment. The cermet coatings have been widely employed in the field of the oil and gas industry for improving the wear resistance and the service life of valves and pipes but their use in the field of road-vehicles-braking-systems has never been explored so far. The present work focuses on the tribological characterization of HVOF coated and heat treated discs performed by means of laboratory-scale-pin-on-disc tribometers at both room and high temperatures (300°C). The sliding speed of 1.57 m/s and the nominal contact pressure of 1 MPa used for this characterization have been selected in order to replicate the actual contact conditions between brake pads and brake discs during an urban cycle braking action. Since the use of lab-scale experimental apparatuses, these tests have not been meant to reproduce real braking conditions for which specific dyno bench tests have been performed in further characterization tests. The pins used during the PoD characterization, made of three different commercially-available friction materials, had dimensions of 12 mm in height and 6 and 10 mm in diameter. The discs, 6 mm in thickness and 58.9 mm in diameter, were coated with a 70 µm thick layer of cermet materials. The heat treated discs had the same dimensions of the coated ones. The tested specimens have been machined from the real braking components, the pins have been extracted from the brake pads while the discs from the braking tracks of the rotors. Since the novelty of the application of the HVOF coatings in the field of braking systems, two preliminary studies of the surface parameters of the coated discs and of the running-in of the pin-disc system have been performed. The first one was conducted on WC-CoCr coated discs polished with different intensities in order to achieve four different average surface roughnesses: 5, 1, 0.1, 0.04 µm respectively. The results of the study highlighted that the wear of the friction material decreased by four order of magnitude by passing from an average surface roughness equal to 5 µm to 0.04 µm. The friction coefficient followed the opposite trend passing from 0.3 for the 5 µm rough coating to 0.7 for the 0.04 µm. The SEM observation of the wear tracks on the discs revealed a high material transfer from the pins in the case of the 5 µm rough coatings due to the abrasive interaction exerted by the hard coating asperities on the relatively soft friction material. The compactness of the material transferred onto the disc surface increased as the average surface roughness of the coating decreased leading to the formation of contact patches also on the coated disc surfaces. From the profilometric analysis of the worn disc their wear resulted negligible. The EDXS analysis of the secondary plateaus of pins detected an increasingly concentration of tungsten and cobalt with the decrease in the surface roughness of the coating meaning that, although the wear of the coating could not be detected from the profilometer, some minor transfer of material occurred during the sliding action. From all the considerations mentioned above the most promising surface roughness, in terms of frictional performances and industrial feasibility, was equal to 1 µm.
The second study aimed at the investigation of the running-in stage of the WC-CoCr and Cr3C2-NiCr coated discs in the as-sprayed (Ra ≈ 5 µm) and polished conditions (Ra ≈ 1 µm). From this former investigation the polishing procedure of the coated discs was found fundamental in order to reach the best frictional and wear performances; the spontaneous surface modifications occurring during pin-on-disc tests were not as efficient as the controlled polishing procedure in reducing the surface parameters of the coated discs and so in improving their performances.
On the basis of the results of the two former studies presented above, the tribological characterization at both room and high temperature (300°C) of the WC-CoCr, Cr3C2-NiCr, WC-Cr3C2-CoCr, WC-FeCrAlY coated discs and of the heat treated one was performed on specimens with an average surface roughness at around 1 µm. Three different friction material formulations were used in order to optimize their frictional and wear performances with the disc counterface. In all cases the EDXS analysis detected the presence of the coating elements, i.e. tungsten, cobalt and nickel, inside the secondary plateaus of the friction material. Depending on the abrasive content of the friction materials and on the testing temperature the amount of the transferred elements varied, i.e. a low amount of abrasives and a high testing temperature gave rise to a reduction in the elements transferred on the pin surfaces. The best tribological combination was the coupling between the friction material FMB, i.e. the one with the lowest amount of abrasives, and the WC-FeCrAlY coated disc.
The results attained with the pin-on-disc tribological characterization of the friction materials were validated during full-scale dyno bench tests. These tests were performed on the most promising materials and they had a twofold aim: as mentioned above they were used to validate the results of the tribometer tests and to collect the particulate matter emitted during braking. The analysis of the wear debris highlighted that, in the case of the friction material FM4 slid against the WC-CoCr coated disc, some cobalt was present. From the deeper analysis of the debris resulted that traces of tungsten and cobalt were found only in the coarser fraction of wear debris, collected on the PM1 filter. The coupled SEM+EDXS analysis of the finer particulate matter, with an average aerodynamic diameter varying from 0.25 to 0.054 µm, did not detected the presence of the coating elements. This was consistent with the observations of the PM1 wear debris that identified WC particles with dimensions comparable to that of the initial carbide particle size inside the coatings; the wear mechanism of the coatings seemed to be the carbide pullout from the metallic matrix without the further fragmentation of the particles due to sliding. Nevertheless, during one of the TEM observation of the particles with an average aerodynamic diameter of 0.094 µm the SAED analysis detected the presence of W2C. On the basis of this last observation and considering that the presence of cobalt inside the finest fraction of debris could not be completely disregarded since it could remain stuck on the W2C particles, the selected coating material for the application in braking systems was the WC-FeCrAlY. This conclusion was consistent with the frictional and wear data attained from the PoD tribological characterization that identified the FMB friction material and the WC-FeCrAlY coated discs as the best coupling in terms of frictional and wear behavior.
The study of the thermal behavior of the novel developed braking materials during a pin-on-disc room temperature test was performed by means of a finite element simulation based on the perfect contact approach. The heat flux applied as the thermal input of the model was calculated from the experimental data acquired during the tests. The calibration of the boundary conditions was performed by comparing the experimental curves of the temperatures acquired during the tests with the temperature curves calculated from the FE analysis. The results of the simulations showed that the temperature field during the pin-on-disc tests was influenced from both the friction coefficient and from the thermal properties of the coated discs, i.e. the lower thermal conductivity of the coatings gave rise to a higher average contact temperature with respect the uncoated cast iron discs. The results of FE analysis were then used to propose an analytical relationship that could be used for describing the raise in temperature during a pin-on-disc test without performing further thermal simulations
Learning from noisy data through robust feature selection, ensembles and simulation-based optimization
Full text linkThe presence of noise and uncertainty in real scenarios makes machine learning a challenging task. Acquisition errors or missing values can lead to models that do not generalize well on new data. Under-fitting and over-fitting can occur because of feature redundancy in high-dimensional problems as well as data scarcity. In these contexts the learning task can show difficulties in extracting relevant and stable information from noisy features or from a limited set of samples with high variance. In some extreme cases, the presence of only aggregated data instead of individual samples prevents the use of instance-based learning. In these contexts, parametric models can be learned through simulations to take into account the inherent stochastic nature of the processes involved. This dissertation includes contributions to different learning problems characterized by noise and uncertainty. In particular, we propose i) a novel approach for robust feature selection based on the neighborhood entropy, ii) an approach based on ensembles for robust salary prediction in the IT job market, and iii) a parametric simulation-based approach for dynamic pricing and what-if analyses in hotel revenue management when only aggregated data are available