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¿QUIÉNES FUERON LOS VOLUNTARIOS? Identità, motivazioni, linguaggi e vissuto quotidiano dei volontari italiani nella guerra civile spagnola
Get PDFThis study had the objective of reconstructing motivations, identity construction and political- ideological paths, the daily life and the tensions ideals, although in opposite perspectives, of the Italian volunteers that engaged Spanish civil war in the Republican front inside of the International Brigades, both in troops sent by Mussolini in support of Franco's militias. Taking a cue from the most recent and innovative areas of Italian and Spanish historiography, it is aimed to build a path analysis aimed at critically retrace the events and actions of the Italian volunteers of both sides, from the study of their subjectivity.
Similarly, through the intersection of archival sources, the press and memoirs, has deepened since the data determined by the influence of political myth, such as the Popular Front for the anti-communism for the fascist volunteers, both served as an element of identification and cohesion for those fighters.
In addition, this investigation has to go beyond the point of view of officers, politicians and intellectuals to try to penetrate into the everyday life of these soldiers, from moments of elation for victories and military commitment, to having to relate with the difficulties and brutality of a conflict engaged in a foreign land in a manner and for different reason
La funzione notarile e l'ausilio delle nuove tecnologie
Get PDFThe recent economic and financial crisis has highlighted the propensity of
markets to assess more the reliability of individual countries than their actual economy;
in this perspective, the role of the notary in countries characterized by a system of legal
security is crucial, because it is able to guarantee as much as possible the security of
commercial transactions and to minimize litigation. Not only do individuals gain from
this, including the most vulnerable, but the entire country also benefits. This is what
inspired the present work, in which has been explored the issue, usually neglected by
manuals, of the function performed by the notary, also concerning the reinforcing of the
role through the use of new technologies, and all the problems that arise from such use,
especially concerning security.
In addition, a specific question was analysed, the answer to which is closely
linked to the approach chosen to adhere to the more general issue of the legal form of
notarial functions, namely the question of the nature of notarial tax liability in respect of
obligation to pay the registry tax. This is particularly relevant in view of the
consequences of the adoption of the various doctrinal and jurisprudential guidelines
produced in relation to the proposability of any requests or legal actions for
reimbursement by the notary in case the payment of registry tax exceeds the amount of
tax actually due and, given the introduction of legislation in our legal system concerning
the computerized registration of documents, there is also the problem of identifying what
impact such an introduction may have had on the nature of notarial tax liability in such
situations
L’utilizzo dei grafici nei bilanci delle aziende europee durante la recente crisi finanziaria
Get PDFThis dissertation investigates the use of graphs in the European annual reports during the recent financial crisis.
By analysing the top firms headquartered in France, Germany, Italy and the UK and by comparing the period pre-crisis and the period during the crisis, this study provides a longitudinal and comparative analysis.
An influence of the institutional context on the use of key performance indicators (KPIs) graphs is found. Moreover, a “status quo” behaviour of the firms seem to explain the graphs’ usage over time. In contrast with previous studies that have showed that graphs are used selectively to portray a more favourable picture of the firm’s performance, this study shows that KPIs graphs are not used selectively during the recent financial crisis. In line with impression management theories, firms are more likely to distort KPIs graphs favourably than unfavourably. Finally, the number of financial analysts is found to positively affect both KPIs graphs’ usage and selectivity.
This dissertation provides both theoretical and practical contributions.
From an academic perspective, this study investigates the use of graphs in the annual reports not only in line with impression management theories but also in line with other theories, like the incremental information perspective and the institutional theory.
From a practical perspective, it provides suggestions to the annual reports’ readers and regulators. Readers should read and process the information within the graph carefully, especially because graphs are found to be distorted. Regulators should provide guidelines for a graph’s accurate usage, following the correct design standards
Riqualificazione energetica dell'edilizia storica. Criticità e strategie d’intervento
Get PDFThe pressing need to operate a cost-effective reuse of historic buildings, with the aim of reducing energy and soil consumption, places us in front of a conflict between the observation of the principles of restoration and the limits imposed by European Community law about the energy consumption reduction. In fact, we know that whenever we operate on a "sensitive" heritage, such as the historic-architectural building, we have to consider the possibility of decreasing its cultural and economic value. The transformations of the historic building derive by the necessity of adapting it to contemporary life exigencies, and at the same time of warranting its conservation, at the architectural and urban scale. To achieve this aim, with reference to system component, usually the interventions are carried out almost exclusively in the inner parts of the constructions, because of legal constraints.
The study begins with an analysis of the state of art about energy retrofit of ancient buildings, with particular reference to theory of conservation of architectural heritage and related legislation.
Was also carried out a study on bioclimatic traditional characteristics - nowadays very often forgotten - of the fabric and of some architectural episode, and considers the possibility and the potentiality of the use of ancient and new technologies, to obtain a suitable thermal insulation of housing.
Starting by these considerations, the present work aims to think over some cultural questions, and to show the results of some studies concerning the historical district of Castello in Cagliari, Sardinia.
With reference to this context, specifically, three different buildings typologies will be analysed, emblematic of the urban fabric, and very useful to demonstrate how it is possible to retrain energetically the existing architectural heritage, in full compliance with the modern conservation principles
On the turbulence in negatively Buoyant Jets
Get PDFNegatively buoyant jets (NBJ) have been investigated with both a laboratory simulation (with a Feature Tracking Velocimetry, FTV, technique, to measure
velocity fields) and a numerical simulation (with an Immersed Boundary method, in which the velocity fields are computed by a DNS method and the concentration by a LES method).This phenomenon can be found in a number of practical applications, e.g. the sea discharge of brine from desalination plants through submerged outfalls, oil
or gas drilling facilities and mineral salt industries e.g. from leaching of mineral salts domes, gypsum or acidic wastes from fertilizer factories, etc..
These jets are typically released upwards, with a certain angle on the horizontal, to increase the path before to sink in the seafloor, to maximize the dilution, therefore the NBJs are initially driven from a source of both
momentum, so behave basically as simple jets, far from the outlet the buoyancy prevails, bending the jet similar to a plume. To understand the processes that
govern the dilution is important study the turbulent mixing and the entrainment.
In this work are presented the results, under a large range of conditions (e.g. angle of the diffuser, density of the brine, release into a stagnant environment),
will be shown; in particular, first order statistics, to study the characteristic dimensions of the jet. The second and third order statistics, to study the
turbulent quantities
Metamorfismo varisico dell’Unità tettonica del Monte Grighini,Sardegna centrale
Get PDFMonte Grighini Complex (central Sardinia) consists, from the bottom to the the top of Monte Grighini Unit, Castello Medusa Unit and Gerrei Unit. Monte Grighini Unit is caracterized by medium grade metamorphism evidenced by mineral such garnet, staurolite, andalusite and sillimanite, and by the presence of a syn-kinematic late-Variscan intrusive complex related to a shear zone marked by ultramylonites and cataclasites.
Geological map in scale 1:25000 of the Monte Grighini Complex has been done by combining geo-petrographical data with previous geological and structural data (Musumeci et al., under revision). A lito-stratigraphic column has also been done. That column shows relations between the two formations of the Monte Grighini Unit (from bottom to the top): Truzzulla Formation that consist of metavolcanics, metarkoses and metasandstones, and Toccori Formation formed by quartzites, micaschists, paragneiss, phyllites, graphitic phyllites and marbles.
Monte Grighini Unit has been interested by four deformation phases. The phase D1 is characterized by the blastesis of biotite and potassic white mica; this phase is almost transposed by the D2 deformational phase. The phase D2 is the main foliation both at the outcrop and micro-scale and it is characterized by folds, foliation and blastesis of garnet, staurolite, biotite, potassic white mica, andalusite, sillimanite and cordierite. The phase D3 produces F3 macroscale folds. The D4 deformation phase is related to the development of the shear zone resulting in ultramylonites and cataclasites.
Zircon U/Pb analyses in metavolcanics and metasandstones samples yield 447 ± 4 Ma (Katian – Upper Ordovician) and 419 ± 5 – 450 Ma (Middle Ordovician) respectively. This indicates that the Ordovician calc-alkaline volcanism went on until Upper Ordovician.
Micro-structural, minero-petrographic and chemical data has been done in micaschists and phyllites of Toccori Formation and metamorphic zoneography has changed. Three zones have been set: garnet zone, andalusite and staurolite zone and sillimanite zone. Biotite zone were removed and andalusite zone and staurolite zone were merged.
Mineralogical, structural and minero-chemical analyses shown that garnet of Toccori has compositional zoning in fact, almandine and pirope increasing and grossular and spessartin decrease, from the core to the rim (mineral association: Grt + Wmca + Bt + Qtz ± St ± And). A rare heuedral garnet without compositional zoning was observed in hornfels closed to the intrusive complex.
Pseudosections of garnet and staurolite micaschists, garnet and sillimanite hornfels of Toccori Formation and leucogranite were calculated.
P-T path of micaschists were done through garnet zoning yielding P = 6.5 - 9.5 kbar and T = 450 - 540°C for garnet core and P = 3-5.8 kbar e T = 510-580°C for garnet rim.
The P-T path obtained starts with the baric peak (P = 6.5 - 9.5 kbar) and continues its path to the thermal peak (T = 510 – 580°C). A retrograde path is showing by chlorite and ilmenite growing.
Thermodynamic modeling in garnet and sillimanite hornfels gave P = 3.5 – 4.5 kbar and T = 510 – 575 °C on the basis of garnet composition; these pressure and temperature are compatible to the condition of that obtained modeling garnet rim in zoned garnet.
The emplacement of granitic intrusion conditions has been obtained by the intersection of the solidus curve and silica content in magmatic potassic white mica getting pressures between 4.2 and 5.5 kbar which corresponds to 16-21 km depth. These pressures of emplacement are consistent with those of the thermal peak of micaschists.
A model of Monte Grighini Complex has been done. In the first stage the crustal thickening occurs with development of polyphasic foliations (phases D1 and earlier-D2) under green-schists and amphibolitic facies. During the second stage deformational phase D2 occurs with forming minerals such as biotite, garnet, staurolite, etc in the Monte Grighini Unit. During this stage an incipient shear zone and an early stage granite emplacement occur. In the third stage granites finish its emplacement with a strong developing of shear zone resulting in mylonites and ultramylonites. In the fourth stage the brittle deformation finish. Detachment structure marked by cataclasites occur
Algorithms for the synchrophasor measurement in steady-state and dynamic conditions
Get PDFPhasor measurement units (PMUs) are becoming one of the key issues of power network monitoring. They have to be able to perform accurate estimations of current and voltage signals either under steady-state or dynamic conditions.
The first part of this PhD thesis analyses the impact of the phasor models on the estimation accuracy, focuses on algorithms proposed in the literature for the estimation of phasors and studies their performance under several different conditions.
On the basis of the results of this analysis, in the second part of this thesis an innovative approach to improve the performance of synchrophasor estimation is presented. The method proposes a modified version of the synchrophasor estimation algorithm which uses the non-orthogonal transform defined as Taylor-Fourier Transform (TFT) and which is based on a Weighted Least Squares (WLS) estimation of the parameters of a second order Taylor model of the phasor. The aim of the proposed enhancements is to improve the performance of the algorithm in presence of fast transient events and to achieve a Phasor Measurement Unit that is simultaneously compliant with both M and P compliance classes, suggested by the synchrophasor standard IEEE C37.118.1. In particular, while the TFT based adaptive algorithm is used for synchrophasor estimation, frequency and Rate of Change of Frequency (ROCOF) are estimated using the higher derivatives outputs of the adaptive TFT. Frequency estimation feedback is used to tune the algorithm and achieve better performance in off-nominal conditions. The proposed approaches are validated by means of simulations in all the static and dynamic conditions defined in the standard.
In the last chapter, the algorithm proposed above is used in a novel architecture, compliant to IEC 61850, for a distributed IED-based PMU, to be used in electrical substations. In particular, a measurement architecture based on process bus and sampled values synchronized with IEEE 1588-2008 is proposed, so that voltage and current signals are acquired by a Merging Unit device, while the PMU signal processing is performed on a IED (Intelligent Electronic Device), in compliance with IEEE C37.118.1-2011
Managing vessel arrival uncertainty in container terminals: a machine learning approach
Get PDFA container terminal is a complex system where a broad range of operations are
carried out involving a wide array of resources that need to interact over a 24 hour
operating cycle. Since the various activities are mutually related to each other, there is
a need not only to maximise the efficiency of each one, but also to ensure proper
coordination, hence to solve integrated decision-making problems. Several factors can
affect the quality of the services provided and the overall efficiency. Vessel arrival
uncertainty further complicates the task of the planners and, as a result, of the
effectiveness of the planning itself, in particular at the operational level. Each arrival
produces high peak loads for other terminal activities, as well as for the supporting
arrival activities (pilotage, towage, etc.) and hinterland transportation (waiting,
congestion etc.). Deviating arrivals only worsen this peak load.
On a daily level, the actual time of arrival of the vessels often deviates from the
scheduled time. Despite contractual obligations to notify the Estimated Time of
Arrival (ETA) at least 24 hours before the arrival, ship operators often have to adapt
and update the latest ETA due to unexpected circumstances. This aspect results in a
last-minute change of plans in terminal operations resulting in higher costs. In fact, the
ability to predict the actual time of a vessel’s arrival in a port 24 hours in advance is
fundamental for the related planning activities for which the decision-making
processes need to be constantly adapted and updated. Moreover, disruptions in
container flows and operations caused by vessel arrival uncertainty can have cascade
effects within the overall supply chain and network within which the port is part.
Although vessel arrival uncertainty in ports is a well-known problem for the scientific
community, the literature review highlights that in the maritime sector the specific
instruments for dealing with this problem are extremely limited.
The absence of a reference model that specifies the relationship between vessel arrival
uncertainty and the involved variables resulted in the application of a specific machine
learning approach within the Knowledge Discovery in Database process. This
V
approach, that abandons all prior assumptions about data distribution shape, is based
on the self-learning concept according to which the relation between an outcome
variable Y and the set of predictors X is directly identified from the historical collected
data.
The approach has been validated thanks to two different case studies: the container
terminal of Cagliari, located in the Mediterranean basin, and one of the main container
terminals of Antwerp, located at the North Sea.
Depending on the framework and planning purposes several estimates can provide
useful information on vessel arrivals. Sometimes, it can be useful for planners to infer
a quantitative estimate of the delay/advance in minutes, sometimes it may be useful to
have a qualitative estimate, even only knowing whether or not an incoming vessel is
likely to arrive before or after the scheduled ETA. For this reason a two-step
instrument is proposed is made up of two different modules.
The fitted algorithmic models used to obtain predictions are Logistic Regression,
CART (Classification and Regression Trees) and Random Forest. All the proposed models are able to learn from experience, following the well-known Data Mining paradigm “learning from data”. From a practical point of view, the probability, associated to the continuous estimation, of specifically identifying the work-shift of the incoming vessel is calculated. In all predictions Random Forest algorithms still show the best performance. This aspect can help planners, in the daily strategy decision making process, in order to improve the use of the human, mechanical and spatial resources required for handling operations. This could maximise terminal efficiency and minimise terminal costs, hence improving terminal competitiveness. Moreover, the interpretation of the discovered knowledge, made it possible to evaluate
the most discriminating variables of the analysis, even thanks to graphical visualisation of the Importance-plots
Stability of dental alloys in artificial saliva: an electrochemical and XPS investigation
Get PDFAlloys used in dentistry should have good mechanical properties and a very high corrosion
resistance in order to be considered biocompatible. The oral cavity is a potentially highly
corrosive environment thus stainless steels have been used frequently. Due to allergic
reactions of about 10% of the population to nickel ions new nickel-free stainless steels have
been developed. In this PhD thesis the Ni-free stainless steel DIN 1.4456 has been studied
with electrochemical and XPS surface analytical techniques at 25°C and at 37°C. Surface
analysis has shown that the alloy in artificial saliva forms a protective passive film at both
temperatures. At 25°C the oxy-hydroxide film formed is enriched in oxidized chromium, after
long immersion times (7 days) the nominal composition of oxidized manganese (18%) is
found. Molybdenum in the film is slightly enriched. Angular resolved XPS performed on
samples exposed at 37°C clearly indicate that the outer part of the passive film is composed
essentially of iron oxy-hydroxide whereas chromium oxy-hydroxide is located at the inner
part. Experiments with argon ion sputtering confirm that the inner part of the film is
enriched in oxidized chromium and manganese whereas oxidized iron is strongly depleted.
Both angle-resolved XPS and experiments with argon ion sputtering show that the alloy
beneath the passive film is depleted in manganese.
The kinetics of initial dissolution and film formation are more rapid at 37°C compared to
25°C but seem to follow the same mechanism. At 37°C the initial corrosion rate is much
higher but its decrease with time is more rapid. After 24 h the dissolution rate is already
lower then 0.2 μm/year, the steady state dissolution rate will be at least one decade lower.
This very low dissolution rate has been confirmed by ICP solution analysis where the metal
ion concentration was found to be below the detection limit of the technique for all the alloy
elements.
Finally a model is proposed that might explain the surface films formed after exposure to
artificial saliva solution. During the short initial period with a relatively high corrosion rate
iron and especially manganese (non-noble elements) dissolve. Chromium is the film-forming
element and an inner chromium oxy-hydroxide film is formed. This film limits progressively
the dissolution of the alloy: with time an outer iron oxy-hydroxide film is formed. Due to the
dissolution of manganese, the manganese content immediately below the film is strongly
depleted. On the contrary, molybdenum is present with about 7%. Such a layered structure of the surface is responsible for the high corrosion resistance and biocompatibility of the DIN 1.4456 stainless stee
Effetti dell'astinenza da morfina in un modello computazionale di un neurone dopaminegico
Get PDFDopamine (DA) neurons of the ventral tegmental area (VTA) are involved in the neurobiological mechanisms underlying addictive processes. It has been shown that withdrawal from drugs of abuse, causes profound modifications in the morphology and physiology of these neurons, but the
mechanisms underlying these modifications are poorly understood. Because of their high predictive value, computational models are a powerful tool in neurobiological research, and have been used to gain further insights and deeper understanding on the molecular and
physiological mechanisms underlying the development of various psychiatric disorders.
Here we present a biophysical model of a DA VTA neuron based on 3d morphological reconstruction and electrophysiological data from literature, showing how opiate withdrawal-driven morphological and
electrophysiological changes could affect the firing rate and pattern of these neurons.
The model is composed by 89 membrane segments, with sodium and calcium dynamics responsible for the basal in vivo activity of these neurons; the set of inputs is modeled adding GabaA and AMPA/NMDA synapses, activated in such a way to model the behavior of gabaergic and
glutamatergic inputs, respectively. We modeled the opiate withdrawal state by applying to the model morphometric modifications observed experimentally and by modulating the balance of Gaba/Glu inputs as described by electrophysiological data. Our results suggest that changes in the balance of Gaba/Glu inputs could explain the hypofunction of VTA DA neurons with different effects on synaptic efficacy, while morphological changes could be responsible for their higher responsivity
to opiate administration observed during opiate withdrawal