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Cost-Benefit Analysis Using GIS: an Application to the Forest Bioenergy sector
No full textThis doctoral thesis introduces a novel methodology to optimize the use of forest biomass for energy purposes at regional scale, by means of GIS applications and economic tools. The procedure calculates, at first, the energy potential of a given forested area, as well as a reasonable location and dimension of a district heating power plant, based on local energy availability and energy demand. In a second step, it runs a cost-benefit analysis (CBA) to assess the economic feasibility of the plant. The CBA considers financial costs and benefit, social benefits and environmental costs, estimated by means of market and non-market valuation techniques. Financial, social and environmental flows are combined to produce four different scenarios, for which the net present value is calculated. Afterwards, a probabilistic sensitivity analysis is carried out, to assess the stability of the results when different assumptions of input values are included. Such procedure have been tested in an Italian case study, the valleys of Gesso and Vermenagna in the Piedmont region. These alpine valleys are interesting, because forests are at present under-utilized. At the same time, the presence of the Alpi Maritime Natural Park provides constraints to the use of natural resources; for these reasons, a carefull planning of the activities is fundamental to assure sustainability. The GIS methodology has been developed in GRASS GIS and automatized in python, while econometric computations were carried out in R. This procedure may facilitate energy planning and increase the efficiency of the forest-timber-energy chain
Numerical Methods for Compressible Multi-phase flows with Surface Tension
No full textIn this thesis we present a new and accurate series of computation methods for compressible multi-phase flows with capillary effects based upon the full seven-equation Baer-Nunziato model. For that reason, there are some numerical methods to obtain high accuracy solutions, which will be shown here. First, a high resolution shock capturing Total Variation Diminishing (TVD) finite volume scheme is used on both Cartesian and unstructured triangular grids. Regarding the TVD finite volume scheme on the unstructured grid, time-accurate local time stepping (LTS) is applied to compute the solutions of the governing PDE system, in which the results are also compared with time-accurate global time stepping. Second, we propose a novel high order accurate numerical method for the solution of the seven equation Baer-Nunziato model based on ADER discontinuous Galerkin (DG) finite element schemes combined with a posteriori subcell finite volume limiting and adaptive mesh refinement (AMR).
In multi-phase flows, the difficulty is to design accurate numerical methods for resolving the phase interface, as well as the simulation of the phenomena occurring at the interface, such as surface tension effects, heat transfer and friction. This is because of the interactions of the fluids at the phase interface and its complex geometry. So the accurate simulation of compressible multi-phase flows with surface tension effects is currently still one of the most challenging problems in computational fluid dynamics (CFD). In this work, we present a novel path-conservative finite volume discretization of the continuum surface force method (CSF) of Brackbill et al. to account for the surface tension effect due to curvature of the phase interface. This is achieved in the context of a diffuse interface approach, based on the seven equation Baer-Nunziato model of compressible multi-phase flows. Such diffuse interface methods for compressible multi-phase flows including capillary effects have first been proposed by Perigaud and Saurel. Regarding the high order accuracy of a diffuse interface approach, the interface is captured and allowed to travel across one single possibly refined cell, and is computed in the context of multi-dimensional high accurate space/time DG schemes with AMR and a posteriori sub-cell stabilization. The surface tension terms of the CSF approach are considered as a part of the non-conservative hyperbolic system. We propose to integrate the CSF source term as a
non-conservative product and not simply as a source term, following the ideas on path conservative finite volume schemes put forward by Castro and Parés. For the validation of the current numerical methods, we compare our numerical results with those published previously in the literature
Advanced methods for the analysis of multispectral and multitemporal remote sensing images
Get PDFThe increasing availability of new generation remote sensing satellite multispectral images provides an unprecedented source of information for Earth observation and monitoring. Multispectral images can be now collected at high resolution covering (almost) all land surfaces with extremely short revisit time (up to a few days), making it possible the mapping of global changes. Extracting useful information from such huge amount of data requires a systematic use of automatic techiques in almost all applicative contexts. In some cases, the strict application requirements force the pratictioner to develop strongly data-driven approaches in the development of the processing chain. As a consequence, the exact relationship between the theoretical models adopted and the physical meaning of the solutions is sometimes hidden in the data analysis techniques, or not clear at all. Altough this is not a limitation for the success of the application itself, it makes however dicult to transfer the knowledge learned from one specic problem to another. In this thesis we mainly focus on this aspect and we propose a general mathematical framework for the representation and analysis of multispectral images. The proposed models are then used in the applicative context of change detection. Here, the generality of the proposed models allows us to both: (1) provide a mathematical explanation of already existing methodologies for change detection, and (2) extend them to more general cases for addressing problems of increasing complexity. Typical spatial/spectral properties of last generation multispectral images emphasize the need of having more exible models to image representation. In fact, classical methods to change detection that have worked well on previous generations of multispectral images provide sub-optimal results due to their poor capability of modeling all the complex spectral/spatial detail available in last generation products. The theoretical models presented in this thesis are aimed at giving more degrees of freedom in the representation of the images. The eectiveness of the proposed novel approaches and related techniques is demonstrated on several experiments involving both synthetic datasets and real multispectral images. Here, the improved flexibility of the models adopted allows for a better representation of the data and is always followed by a substantial improvement of the change detection performance
The social reproduction of licensed professionals : a micro-class approach
No full textIt assesses how processes of social closure enhance intergenerational immobility in the regulated professions and thus promote persistence at the top of the occupational hierarchy. I compare five European countries (Great Britain, Germany, Denmark, Sweden and Italy) that differ
considerably in their degree of professional regulation and in their broader institutional arrangements. I run log-linear and multinomial logistic regression models on e datasets with detailed information at the level of unit
occupations. Analyses indicate that children of licensed professionals are far more likely to inherit the occupation of their parents and that this stronger micro-class immobility translates into higher chances of persistence in the upper class. These results support social closure theory and confirm the relevance of a micro-class approach for the explanation of social fluidity and of its cross-national variations
Per la critica della concettualità politica moderna. Walter Benjamin e il monopolio della Gewalt.
Get PDFSe il compito che si prefiggeva Benjamin in Per la critica della violenza era l’esposizione dei rapporti che intercorrono tra violenza, diritto e giustizia, situare la relazione che lega questi tre concetti in un contesto storico-politico è lo scopo del presente lavoro. Il contesto storico-politico scelto è quello delle moderne democrazie occidentali. Nel primo capitolo, viene portato alla luce il rapporto tra il filosofo ebreo-tedesco Benjamin e il giurista Carl Schmitt, entrambi critici della breve – e travagliata – parentesi di parlamentarismo liberale che la Germania si era data con la Repubblica di Weimar. Si è individuato come luogo privilegiato attraverso il quale esaminare le divergenze e, in un senso molto peculiare, le somiglianze tra i due pensatori, nello stato di eccezione quale concetto-limite del diritto. L’ipotesi che si è provato ad avanzare nel corso del secondo e terzo capitolo è che il diritto, pur mantenendo la sua funzione inalterata – che è, per Benjamin, quella di essere strumento di oppressione –, ha, nelle sue realizzazioni concrete, delle peculiarità diverse a seconda delle fasi storiche e politiche in cui viene esercitato. Per analizzare i modi diversi in cui il diritto, a seconda della fasi storiche e dalle forme politiche in cui viene esercitato, fa presa sul vivente, si è partiti dalla cosiddetta «preistoria» del diritto, illustrata da Benjamin nel saggio dal titolo Franz Kafka. Per il decimo anniversario della sua morte, e, passando per Destino e carattere e per i saggi dedicati al linguaggio (Sulla lingua in generale e sulla lingua dell’uomo e Il compito del traduttore), si è arrivati ad analizzare le specificità prettamente moderne del diritto espresse in Per la critica della violenza.
Non avendo Benjamin dedicato alcuno scritto alla successione temporale di sistemi giuridici, né avendo mai dichiarato di volerne delineare una storia, è con estrema cautela che abbiamo rilevato le caratteristiche delle diverse fasi del diritto (o temporalità giuridiche, come si è voluto chiamarle nel secondo capitolo) nella sua opera, senza giungere a tracciare un susseguirsi lineare da una all'altra, e evidenziandone, anzi, le sovrapposizioni e i rimandi. L’analisi della violenza giuridica – e della violenza pura che ha per compito la dissoluzione del legame tra quella e l’uomo – è stata riportata alla questione del monopolio della violenza da parte del diritto, tratto che Benjamin rinveniva nelle legislazioni europee a lui contemporanee. Nel secondo capitolo, si è cercato di rinvenire i riferimenti precisi alla situazione politica in cui Benjamin si trovava al momento della stesura del saggio, quindi alla Repubblica di Weimar e alla legislazione a lui contemporanea, oltre ad alcuni rimandi alla democrazia come orizzonte interpretativo della forma politica di riferimento. Sin dalle prime pagine del saggio, Benjamin riconosce di basare la sua Critica sulle legislazioni europee moderne. Secondo Benjamin, infatti, per essere compresa, la finalità della violenza deve essere posta in relazione con una fattispecie determinata di rapporti giuridici, ed egli dichiara che, «per semplicità», nel corso del saggio farà riferimento «alle presenti legislazioni europee». A partire dai rapporti giuridici moderni, Benjamin rintraccia una loro «massima generale», che riassume nella tendenza all’onnipervasività del diritto, riscontrabile anche nelle legislazioni attuali, oltre a citare esempi di violenza squisitamente moderni (la lotta di classe, i differenti tipi di sciopero, il servizio militare obbligatorio, le critiche ad esso – risalenti al periodo della Prima guerra Mondiale –, la polizia come istituzione moderna, i parlamenti). Una delle novità della concettualità politica moderna che abbiamo individuato è rappresentata dal fatto che, nella modernità, il potere politico non trova alcuna opposizione di fronte a sé, in quanto i singoli hanno riconosciuto come loro proprie le azioni di colui che detiene il potere supremo. È così legittimato il monopolio della Gewalt, in quanto fondato sulla volontà di tutti.
Conseguentemente ha acquisito grande rilievo la preferenza accordata da Benjamin nel testo Per la critica della violenza alla polizia monarchica rispetto a quella democratica. In tale passaggio, Benjamin afferma che la polizia «nelle democrazie […] testimonia la massima degenerazione pensabile della violenza» – una presa di posizione che non può non sbalordire, e che rappresenta una scossa nei confronti dell’ordine di concetti attraverso i quali la società democratica si autointerpreta. Provare a darne ragione è stata l’occasione per testare la percorribilità di un’interpretazione del saggio volta ad individuare, in esso, i tratti specifici della modernità giuridico-politica, ma anche per tematizzare il monopolio della Gewalt da parte dello stato moderno e, coerentemente con gli obiettivi dichiarati del presente lavoro, per fuoriuscire dall’autoreferenzialità della forma politica democratica. Attraverso l’interpretazione di Jacques Derrida del passo, ma soprattutto nella mancata adesione alle sue conclusioni, si è tentato di dare ragione della posizione benjaminiana in termini di filosofia politica.
Individuate le specificità del diritto e della forma politica moderni, abbiamo cercato di analizzare il concetto-limite di ogni teoria della sovranità, ovvero il concetto di guerra civile. Lo si è fatto a commento dell’ottava tesi sul concetto di storia, considerata l’ultimo atto della battaglia teorica che ha visto contrapporsi Carl Schmitt e Walter Benjamin intorno allo statuto della legge nello stato di eccezione. In essa, Walter Benjamin contrappone a uno «stato di eccezione in cui viviamo» che «è la regola» un «vero stato di eccezione». Assunto questo punto di partenza, si è tentato, nel quarto capitolo, di elaborare una concezione della guerra civile che fosse utile per illuminare i rapporti tra Stato e diritto, in un’ottica di sostanziale continuità della guerra civile con l’esercizio del potere costituito: la guerra civile come stato di eccezione. Si è pervenuti a una concezione della guerra civile non nei termini dell’avvenuta perdita di controllo da parte del sovrano sulla società civile, o della dissoluzione della civitas, bensì come di uno dei modi del gerere rem publicam, una tecnica di esercizio del potere sovrano.
Si è quindi aderito a una concezione dello stato di eccezione opposta a quella classica e vicina a quella tradizione che, da Marx, a Benjamin, a Korsch, individua in essa una condizione permanente. Abbiamo visto come la guerra civile non sia mai del tutto esclusa dalla vita politica e come il moderno Stato rappresentativo possa essere definito come l’ente che informa il conflitto civile, che definisce le parti in gioco, che sanziona le vittorie delle parti tramite il diritto e che può, in ogni caso, sospenderlo, ma che non ha interesse a mettervi fine.
In questa ottica, il saggio giovanile Per la critica della violenza trova il suo epilogo nell'ottava delle Tesi sul concetto di storia, ultimo testo scritto da Benjamin prima della morte. Di più, l’individuazione nel rapporto mezzi-fini dell’architrave dell’ordine giuridico consente di fare della nozione di Aufgabe, che ritorna più volte nell'opera benjaminiana, un termine tecnico del lessico del filosofo tedesco che indica una prassi libera dalla strumentalità e dalla finalità, e, quindi, una prassi messianica
Development of Small-Pitch, Thin 3D Sensors for Pixel Detector Upgrades at HL-LHC
No full text3D Si radiation sensors came along with extreme radiation hard properties, primarily owing to the geometrical advantages over planar sensors where electrodes are formed penetrating through the active substrate volume. Among them: reduction of the inter-electrode distance, lower depletion voltage requirement, inter-columnar high electric field distribution, lower trapping probability, faster charge collection capability, lower power dissipation, and lower inter-pitch charge sharing. Since several years, FBK has developed 3D sensors with a double-sided technology, that have also been installed in the ATLAS Insertable B-Layer at LHC. However, the future High-Luminosity LHC (HL-LHC) upgrades, aimed to be operational by 2024, impose a complete swap of current 3D detectors with more radiation hard sensor design, able to withstand very large particle fluences up to 2×1016 cm-2 1-MeV equivalent neutrons. The extreme luminosity conditions and related issues in occupancy and radiation hardness lead to very dense pixel granularity (50×50 or 25×100 µm2), thinner active region (~100 µm), narrower columnar electrodes (~5µm diameter) with reduced inter-electrode spacing (~30 µm), and very slim edges (~100 µm) into the 3D pixel sensor design. This thesis includes the development of this new generation of small-pitch and thin 3D radiation sensors aimed at the foreseen Inner Tracker (ITk) upgrades at HL-LHC
On Semi-isogenous Mixed Surfaces
No full textLet C be a compact Riemann surface. Let us consider a finite group acting on CxC, having some elements that exchange the factors, and assume that the subgroup of those elements that do not exchange the factors acts freely. We call the quotient a Semi-isogenous Mixed Surface. In this work we investigate these surfaces and we explain how their geometry is encoded in the group. Based on this, we present an algorithm to classify the Semi-isogenous Mixed Surfaces with given geometric genus, irregularity and self-intersection of the canonical class. In particular we give the classification of Semi-isogenous Mixed Surfaces with K^2>0 and holomorphic Euler-Poincaré characteristic equal to 1, where new examples of minimal surfaces of general type appear. Minimality of Semi-isogenous Mixed Surfaces is discussed using two different approaches. The first one involves the study of the bicanonical system of such surfaces: we prove that we can relate the dimension of its first cohomology group to the rank of a linear map that involves only curves. The second approach exploits Hodge index theorem to bound the number of exceptional curves that live on a Semi-isogenous Mixed Surface
Dissociative charge transfer of organic molecules induced by collisions with the He+ cation. A joint experimental and theoretical study of relevance for the interstellar medium evolution
Get PDFCollisions with He+ are an important pathway for the destruction of complex organic molecules in the interstellar medium (ISM). We have carried out dissociative charge transfer reactions of He+ with two oxygen containing organic molecules, ubiquitous in ISM: dimethyl ether (DME, CH3OCH3 ) and methyl formate (MF, HCOOCH3). Since they have a prebiotic relevance, several models were developed to explain how these molecules are formed and destroyed in the ISM. The reactions have been investigated by using the home-built Guided-Ion Beam Mass Spectrometer (GIB-MS) apparatus. Absolute cross sections and branching ratios of the products have been measured as a function of the collision energy in the hyperthermal energy range (i.e. from about 0.1 eV to 7 eV). The presence of the molecular ion was not observed among the products for these reactions, which means that the nascent DME and MF radical cations are formed in a dissociative state. Insights on both the charge transfer processes have been obtained by investigating the nature of the non-adiabatic transitions between the reactant and product potential energy surfaces (PES). The PES has been represented by using a semi-empirical method to model the inter-molecular interactions. To explain the experimental evidence, two excited states of DME and MF radical cations have been invoked: He+ captures an electron from inner valence orbitals of both the organic molecules, having binding energies ~10 eV higher than the HOMO. An improved Landau-Zener-Stückelberg model has been developed to obtain the total integral cross-section to be compared with the experimental results. Inter-molecular interaction and electron densities of the orbitals involved in the reaction turned out to be key points to describe the dynamics of the two studied dissociative charge transfers. A very good agreement is obtained between the experimental and calculated total cross-sections at low collision energy, which is the most relevant range for the interstellar environment. These results represent a significant starting point to estimate rate constants for the total dissociation of DME and MF by collisions with He+ ions in the ISM at low temperatures
Intrinsic Differentiability and Intrinsic Regular Surfaces in Carnot groups
Get PDFThe main object of our research is the notion of "intrinsic regular surfaces" introduced and studied by Franchi, Serapioni, Serra Cassano in a Carnot group G. More precisely, an intrinsic regular hypersurface (i.e. a topological codimension 1 surface) S is a subset of G which is locally defined as a non critical level set of a C^1 intrinsic function. In a similar way, a k-codimensional intrinsic regular surface is locally defined as a non critical level set of a C^1 intrinsic vector function. Through Implicit Function Theorem, S can be locally represented as an intrinsic graph by a function phi. Here the intrinsic graph is defined as follows: let V and W be complementary subgroups of G, then the intrinsic graph of phi defined from W to V is the set { A \cdot phi(A) | A belongs to W}, where \cdot indicates the group operation in G. A fine characterization of intrinsic regular surfaces in Heisenberg groups (examples of Carnot groups) as suitable 1-codimensional intrinsic graphs has been established in [1]. We extend this result in a general Carnot group introducing an appropriate notion of differentiability, denoted uniformly intrinsic differentiability, for maps acting between complementary subgroups of G. Finally we provide a characterization of intrinsic regular surfaces in terms of existence and continuity of suitable "derivatives" of phi introduced by Serra Cassano et al. in the context of Heisenberg groups. All the results have been obtained in collaboration with Serapioni.
[1] L.Ambrosio, F. Serra Cassano, D. Vittone, \emph{Intrinsic regular hypersurfaces in Heisenberg groups}, J. Geom. Anal. 16, (2006), 187-232
Characterization of Small Molecules Inhibiting the RNA Binding Protein HuR
Get PDFHuR, the ubiquitously expressed member of the ELAV (embryonic lethal abnormal vision) family of RNA binding proteins, selectively binds to AREs (AU-rich elements) and mainly stabilizes ARE-containing mRNAs, e.g. TNFα, VEGF, c-FOS, favoring specific protein translation. TNFα mRNA is one of the most important target mRNA of HuR since the protein encoded by this gene mediates the inflammatory response and its overexpression is correlated with autoimmune diseases and cancer-related inflammation. Specific drugs are already available that can inhibit TNFα protein but cause important side-effects, as insurgence of tumoral pathologies, due to high immunodepression. Therefore, inhibition of TNFα mRNA translation by specific inhibitors targeting HuR, only in those cells undergoing pathological anomalies, is an alternative, intriguing novel therapeutic approach that deserves investigation. By REMSA and AlphaScreen assays we identified a family of low molecular weight inhibitors, called Tanshinones, among which DHTS-I (Dihydrotanshinone – I) was the most potent. Tanshinones are well known in the traditional Chinese Medicine Practice, and these anti-inflammatory agents possess the ability to prevent HuR-RNA complex formation in vitro. We further identified structural determinants of HuR and DHTS interaction using RRM1&RRM2 tandem domains. EMSA and AlphaScreen experiments, with truncated ΔRRM1 and mutants revealed that DHTS is a competitive binder of HuR with respect of target RNA. To ameliorate the solubility of DHTS, we synthesized a number of DHTS analogs, of which the most potent and soluble compound was named MFM49. We evaluated the anti-inflammatory potential of DHTS and DHTS analogs and the HuR-dependent mechanism of action, revealing that, at least in part, DHTS and DHTS analogs rely on HuR to exert their mechanism of action. Influence on NF-kB activation by DHTS and MFM49 upon LPS co-stimulation was not seen in immunofluorescence studies. So here, we disclose a previously unrecognized molecular mechanism of action exerted by DHTS, and anti-inflammatory potential of DHTS analogs opening new perspectives to therapeutically target the HuR mediated, post-transcriptional control in inflammation and cancer like anomalies