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Evaluating the Additionality of Innovation Policy: An Investigation at Different Levels of Analysis
No full textThe present Thesis, in the form of a collection of three essays, provides a contribution to the literature on the effects of the public support to innovation activities.
The first paper aims at providing a review and a critical discussion of the literature dealing with the additionality of innovation policy, that is, the net effects of the public support that would not have occurred in the absence of the policy. In particular, the paper focuses on the behavioural dimension of the additionality concept, i.e. the strategic and behavioural changes induced by the policy. In the first part, the paper argues that the behavioural dimension, though not yet clearly defined, provides a necessary complement to the input and output dimensions, when assessing innovation policies consistently with the evolutionary theory and the related innovation system perspective. In the second part, the paper organises and reviews the recent empirical works that have tried to measure, with econometric and quantitative methods, the strategic and behavioural changes induced by the policy interventions. In so doing, it presents some main methodological issues that characterise the investigation of the behavioural additionality, as well as the main behavioural changes that public support to innovation activities can induce.
Starting from the framework provided in the first paper, the Thesis proposes two empirical applications. The first of these is presented in the second paper. This aims at proposing and applying a new multi-level and multi-dimensional evaluation of the additionality effects of innovation policy. The impacts of national and regional support schemes are jointly investigated (multi-level), by simultaneously analysing their input, output and behavioural additionality effects (multi-dimension). By making use of micro-data on manufacturing firms stemming from the 4th wave of the Community Innovation Survey, an empirical application of this kind of assessment is provided for two EU countries, namely Italy and Spain. To control for the selection bias, the econometric strategy is based upon a set of propensity score matching estimations of the average treatment effect on the treated (ATT). The picture of the results is quite complex. In both countries, only national policies increase R&D investment. On the other hand, their regional and national interventions induce additional innovation performances and innovation behaviours of different nature. The proposed methodology is integrated with an original, although somehow tentative, analysis of the relation between the average additionality effects of the policies and the dispersion of their impacts. With the exception of Italian regional policies, the higher is the average additionality level, the lower is found to be the polarisation of the policy effect.
The third paper included in the Thesis, has a more narrow focus. It aims at identifying the extent to which regional innovation policy affects firms’ innovation behaviour. Some research hypotheses are put forward. At first, the policy support is supposed to induce relevant changes in the beneficiaries' behaviour, which can help to solve potential regional system failures. Moreover, an increasing amount of regional subsidy is expected to enhance the geographical range of the cooperation with universities and research institutes, allowing firms to interact with “global best” and more suitable research partners. These hypotheses are tested with respect to a sample of manufacturing firms located in the NUTS-2 Emilia-Romagna region of Italy, by making use of a unique dataset including information on pre-policy characteristics and post-policy behaviours. The econometric strategy is based, at first, on a set of propensity score matching estimations. The recently developed generalised propensity score method, which is suitable for a continuous treatment framework, is also employed. At first, the policy is found to enhance the competencies’ upgrading of the beneficiaries, as well as their interactions with both regional and extra-regional research organisations. Furthermore, the amount of subsidy is found to be important to extend beyond the regional borders the cooperation with research partners: over a minimum efficient scale of public funding, an increase in the subsidy enhances the propensity to cooperate with extra-regional universities and research institutes
Approximate Explicit MPC and Closed-loop Stability: Analysis based on PWA Lyapunov Functions
No full textModel Predictive Control (MPC) is the de facto standard in advanced industrial automation systems. There are two main formulations of the MPC algorithm: an implicit one and an explicit MPC one. The first requires an optimization problem to be solved on-line, which is the main limitation when dealing with hard real-time applications. As the implicit MPC algorithm cannot be guaran- teed in terms of execution time, in many applications the explicit MPC solution is preferable. In order to deal with systems integrating mixed logic and dynam- ics, the class of the hybrid and piecewise affine models (PWA) were introduced and tackled by the explicit MPC strategy. However, the resulting controller complexity leads to a requirement on the CPU/memory combination which is as strict as the number of states, inputs and outputs increases. To reduce drasti- cally the complexity of the explicit controller while preserving the controller’s performance, a strategy combining switched MPC with discontinuous simpli- cial PWA models is introduced in this thesis. The latter is proven to be circuit implementable, e.g., in FPGA. To ensure that closed-loop stability properties are guaranteed, a stability analysis tool is proposed which exploits suitable and possibly discontinuous PWA Lyapunov-like functions. The tool requires solving offline a linear programming problem. Moreover, the tool is able to compute an invariant set for the closed-loop system, as well as ultimate boundedness and input-to-state stability properties
Word Recognition in Predictive Contexts
No full textOver the last years several results demonstrated that context-based expectations on both word-class and concepts influence the word processing at very early stages, namely at sensory analysis level. Given that these early effects are modulations of the process of stimulus analysis they depend on physical and orthographical properties of critical words in interaction with linguistic expectations. This evidence on early effects is in contrast with a syntax-first approach for which the cognitive system builds at first the syntactic structure by exploiting word-class information only. This strong syntax-first assumption pushed forward by Friederici (2002) model is based on a very early ERPs effect with latency around 150 ms that is elicited by word-class violations (eLAN: early left-anterior negativity). I studied three linguistic violations with an ERPs sentence processing paradigm. In two studies in Italian word-class violations on prepositions and verbs were implemented, overcoming the more important methodological limitations of previous studies on word-class violations. In a third study we investigated determiner-noun gender agreement in Italian using nouns for which grammatical gender is expressed unambiguously by a long derivational morpheme, that is very salient at orthographic
and visual level. ERPs results show a LAN (300ms latency) followed by a P600 (500ms latency) for all the conditions. The lack of replicability of eLAN, already discussed in the literature, makes Friederici (2002) model difficult to be maintained. The ERPs elicited by gender disagreeing nouns also show an effect on the amplitude of the N250 (200ms onset), an effect specific to morphological processing since a previous study with no control on how gender was expressed reported a LAN+P600 pattern only (Molinaro et al., 2008). The latter result shows that gender agreement can affect word recognition (at least the morphological parsing) during sentence processing earlier than violation detection indexed by the LAN. This result enrich the evidence about early context top-down effects that are different from syntagmatic structural processing
Communication Priorities and Stochastic Measures for Web Services Modeling
No full textService Oriented Architecture is an important trend in the development of services composed of loosely coupled, heterogeneous and interacting components. We first consider COWS, which is a language tailored to model the behavioural aspects of these systems. We analyse the peculiarities of the communication mechanism of the language, a key ingredient in its modelling capabilities, presenting a separation result between a fragment of CCS equipped with global priorities and the fragment of COWS relevant for its communication mechanism. We then consider a stochastic approach to model the quantitative aspects of Web Services through SCOWS, a stochastic extension of COWS. We present a prototype tool, named SCOWS_LTS, for the derivation of the complete representation of the behaviour of a SCOWS model as a Continuous Time Markov Chain. In order to validate the approach, a number of case studies are modelled in SCOWS considering both the SOA and the concurrency literature. Using PRISM as model checker, the results of the simulation phase are analysed using properties written to check the probabilistic behaviours of the considered systems
Insediamenti e paesaggi in val di Non (TN) tra età tadoantica e altomedioevo: nuovi approcci allo studio del paesaggio rurale d'ambito montano
No full textIl contributo in oggetto è relativo allo studio del paesaggio storico dell’area anaune, in particolare della sequenza dei diversi sistemi agrari tra età medievale e prima età moderna. Nella grande maggioranza dei casi si tratta di paesaggi generati dai nuclei inseditivi del territorio e agganciati alla rete viaria locale.
Parallelamente la ricerca si è interrogata sulla distribuzione e sulle forme del popolamento di questo territorio tra età medievale e prima età moderna, con un ulteriore affondo sull’analisi della topografia degli insediamenti (distribuzione e interrelazione tra edifici, luoghi di culto, spazi d’uso, percorsi stradali e infrastrutture).
Oltre al tema dello sviluppo del paesaggio agrario dell’area in oggetto, si è cercato di approfondire gli aspetti della produzione agraria locale (principalmente cereali e vino) e dello sfruttamento delle risorse locali da parte dei diversi attori sociali del territorio (vescovo, enti ecclesiastici, famiglie nobiliari, comunità rurali).
La strategia di ricerca necessaria per rispondere a questi interrogativi si è avvalsa di un approccio multidisciplinare, basato su un continuo gioco di specchi tra vari tipi di fonti: dato archeologico; dato materiale (strutture residenziali, edifici di culto); fotografie aree e immagini Lidar; cartografia storica ed attuale (carte topografiche ante catasto austriaco, CTP, carte catastali ottocentesche ed attuali); documenti d’archivio; macro e microtoponimi attuali e storici.
Altrettanto significativa si è rivelata l’applicazione di un metodo d’analisi regressivo, che, partendo dalla configurazione odierna, ha cercato di risalire alle forme più antiche del territorio in oggetto
Peer Influence and Knowledge Management in Communities of Users and Practices
No full textKnowledge is highly dispersed in companies, customer networks and, more generally, in markets. Various forms of knowledge influence collective results: experiential knowledge derived from shared socialization, practical knowledge, and scientific knowledge. This work aims at better understanding of how these types of knowledge affect collective results in communities of customers and of practice. In particular, collective results are interpreted on one hand as individual commitments in communities of customers, and, on the other, companies’ success in rapidly solving problematic urgencies through communities of practice. First, the effect of both experience and socialization is examined in the service sector, in order to investigate how the social structures of communities of customers influence commitment and retention. Second, communities of practice operating in high-risk sectors are analyzed to look for improvements in their structure by aiding the recombination of dispersed knowledge and more rapid access to those skills and competences required to solve urgent problem-solving processes.
Various methods and tools are used to deal with these issues. In particular, cross network analyses and new methodological approaches, originally applied in the field of social ethology, are applied to study reality-mined data collected by radio-frequency identification (RFID) tags. In addition, a set of recently developed non-parametric methods is devised to deal with new methodological problems arising in studying socialization in networks. Recent debates in the marketing literature have emphasized methodological criticalities in discriminating between peer influence, homophily, and other confounding factors in real-world social settings. A whole chapter is devoted to a methodological contribution to these debates
On the role of mixing in controlling transport of aqueous species in heterogeneous formations
No full textThe fate of reactive solutes in groundwater is largely determined by mixing, since dilution and reactions are controlled by mixing rates. By mixing we refer to the overlap of solute bodies with a different composition, which makes possible the encounter between reacting molecules. Therefore the quantification of mixing has an important role in contamination and risk assessment and remediation technology, when they rely on processes of natural attenuation, biodegradation or chemical delivery. As porous formations are ubiquitously heterogeneous, and heterogeneity features, besides being deterministically unknown, belong to a hierarchy of scales, the description of transport processes has to deal with two main issues: epistemic uncertainty and reference scale. While the heterogeneous nature of porous media interferes with physical and chemical processes (which are inherently related to the quantification of mixing and mixing-controlled processes), the choice of the reference scale is related to the means of modeling the phenomena.
In order to have an accurate representation of mixing at the continuum scale, we develop a few numerical tools, all belonging to the Lagrangian framework, and compare them with classic Eulerian and Eulerian-Lagrangian schemes. Typical transport scenarios are characterized by highly fingered plumes and sharp fringes, and pose several numerical problems (e.g. artificial diffusion and spurious oscillations). In particular, artificial diffusion can in some cases overcome the actual local dispersion, thereby possibly determining gross overestimations of reaction rates. Our numerical tests provide a set of guidelines for a conscious choice of the numerical scheme according to the objectives of the investigation and to the heterogeneity level, highlighting the drawbacks of the numerical schemes on both the evaluation of dilution and of the overall effect of reactions.
Under the assumption of complete mixing at the Darcy scale, we model both instantaneous and kinetically-controlled reactive transport on synthetic bi-dimensional hydraulic conductivity fields in order to investigate the complex interplay among velocity non-uniformities, local dispersion and reaction rates at increasing levels of physical heterogeneity. We also compare the effects of different local dispersion models and injection modes (uniform vs non-uniform), still analyzing the results on a single-realization basis. Realizations share the same log-conductivity structure but are characterized by variances ranging from low (0.2) to high (10).
Resorting to single-realization analysis is uncommon in the literature, unless when ergodicity conditions are fulfilled. On the other hand, ensemble analysis is insensitive to local features and does not often offer a reliable representation of actual field phenomena, especially in non-ergodic conditions. Hence single-realization scenarios can be used for understanding the key processes and their interaction, or for grasping aggregated information on the whole solute body behavior.
Under simplified conditions, that is, limiting the investigation to low heterogeneity fields, these numerical results are compared to simplified Lagrangian semianalytical relations aiming at reproducing plume-averaged quantities. This Lagrangian theory provides relevant information relying on a limited amount of information, i.e. low-order geostatistical properties of the formation, aquifer's geometry, reactive parameters and problem forcings (e.g. initial and boundary conditions for the flow field and the concentration of the involved species). The match between empirical and theoretical global moments is very good in all tested conditions (two different Peclet numbers, a few heterogeneity levels up to log-transmissivity variance equal to 2 and three different source sizes), and also Beta Cumulative Frequency Distributions (CFDs) with shape parameters obtained by substituting the theoretical global moments compare well with the numerical CFDs. As expected, coherent estimates of peak concentration are not equally good, because of an inherently different nature of this quantity as opposed to plume-scale concentration moments.
The a-priori information expressed by statistical analysis both at the global scale and at the local scale for a conservative tracer z can be transferred to reactive species in case of very fast kinetics. Given this useful property of equilibrium reactions, we develop explicit semianalytical relations for the moments and the probability distribution functions of the concentration of chemical species reacting according to a bimolecular equilibrium homogeneous reaction. We assume that the conservative tracer probability distribution function, both at the local scale and at the global scale, can be modeled with a Beta distribution, fully characterized by the mean and the variance of z. Rigorous numerical testing on highly heterogeneous velocity fields confirms that this assumption holds. A few illustrative cases shed some light on the role of the reaction on the time evolution of (local and global) concentration for the different reactive species, and on the different quality of information contained in local statistics as opposed to global statistics. The Beta distribution is a powerful predicting tool for the space and time evolution of passive concentration and, by extension, also for reactive species in particular chemical conditions. Analytical procedures are needed for predicting the z moments, as for example the Lagrangian ones used in the present work, which are limited to weakly heterogeneous formations.
Finally we explore, analytically and numerically, the upscaling from the pore scale to the Darcy scale. Via multiple scale analysis we identify a homogenizability region, in terms of the dimensionless numbers regulating a multicomponent precipitation/dissolution reactive problem, where Darcy-scale (upscaled) transport equations can be used, regardless of sub-Darcy scale inhomogeneities
Essays on Growth and Development in Post-Socialist Countries
No full textThis dissertation seeks to contribute to the ongoing debate on the variety of post-socialist developmental trajectories by analyzing specific country cases and factors. The origins of distinct development paths are traced to early policy decisions, formation of tax regimes, and the shifting balance between demand for, and supply of, redistribution. An important feature of the transition economies is the varying propensity of policy-makers to control the speed of market reforms. Policy discretion has been restricted by self-imposed economic transnationalization, i.e., the opening of the financial and production sectors to the penetration of foreign capital. Post-socialist economies have varied with respect to the timing of their transnationalization and to the strength of the associated monetary and financial discipline, which have far-reaching implications for their competitiveness.
The examination of existing cases of delayed reforms, such as in Belarus, further uncovers the nuances of formation of divergent post-socialist trajectories. This process is riddled with an inescapable conflict between backward and advanced sectors. Domestic social forces are often unable to reach a negotiated, consensual solution to this conflict, thus opening an avenue for transnationalization. If this conflict is left unresolved, dual economies tend to emerge, and are characterized by the coexistence of a sector of subsidized enterprises with a sector of profit-making and more efficient companies.
In order to trace the dynamics of dual economies, the dissertation develops two analytical models encapsulating the factors behind the inter-sectoral conflict and the policy instruments, including taxation and financial repression in the form of directed lending. A continuous use of these policy instruments has clear-cut implications for investment and economic growth over the long run. A case is made to show the conditions under which dual economies are sustained over prolonged periods, but do not necessarily become more efficient and stable. The first model predicts that – ceteris paribus – the speed at which dual economies converge to the income level of the most advanced countries is reduced by the legacies of industrial employment and ideological hostilities towards reforms. The second model, which captures some important properties of the Chinese economy, demonstrates that in dual economies financial repression can lead to economic growth, but it occurs at the expense of savers’ well-being
A tunable Bose-Einstein condensate for quantum interferometry
No full textThe subject of this thesis is the use of BECs for atom interferometry. The standard way atom interferometry is today performed is by interrogating free falling samples of atoms. The employed samples are cold (but not condensed) to have high coherence, and dilute, not to interact significantly with each other. This technique represents nowadays an almost mature field of research in which the achievable interferometric sensitivity is bounded by the atomic shot noise. Until a few years ago the employment of BECs in such devices was strongly limited by the effect of the interactions between the condensed atoms. This obstacle is today removable exploiting interaction tuning techniques. The use of BECs would be advantageous for atom interferometry inasmuch they represents the matter analogue of the optical laser providing the maximum coherence allowed by quantum mechanics. Moreover, non-linear dynamic can be exploited in order to prepare entangled states of the system. The realization of entangled samples can lead to sub-shot noise sensitivity of the interferometers. At today very nice proof-of-principle experiments have been realized in this direction but a competitive device is still missing. This thesis work is inserted in a long term project whose goal is the realization of such a device. The basic operational idea of the project starts with the preparation of a BEC in a double well potential. By the effect of strong interactions the atomic system can be driven into an entangled state. Once the entangled state is prepared, interactions can be ”switched off” and the interferometric sequence performed.
This thesis begins with the description of the apparatus for the production of tunable BECs to be used in the interferometer. We chose to work with 39K atoms because this atomic species presents many convenient Feshabch resonances at easily accessible magnetic field values. The cooling of this particular atomic species presents many difficulties, both for the laser and evaporative cooling processes. For this reason, this was the last alkaline atom to be condensed. Its condensation up to now was only possible by employing sympathetic cooling with another species. In this thesis our solutions to the various cooling issues is reported. In particular we realized sub-Doppler cooling for the first time for this species and we achieved condensation via evaporation in an optical dipole trap taking advantage of a Feshbach resonance. In the last part of this work, are presented original calculations for the effects of thermal fluctuations on the coherence of a BEC in a double well, discussing the interplay between thermal fluctuations and interactions in this system. Estimations and feasibility studies regarding the double well trap to be realized are also reported
Il ruolo delle Corti Supreme latinoamericane nello sviluppo del diritto penale internazionale: tendenze giurisprudenziali nella ricostruzione delle fattispecie incriminatrici
No full textLe Corti Supreme latinoamericane svolgono un ruolo protagonista nell’evoluzione del diritto penale internazionale. La loro giurisprudenza sembra riproporre e confermare una tendenza di portata più ampia, che interessa il diritto penale lato sensu, ad accrescere sempre più il ruolo dei giudici nella funzione propriamente normopoietica, fino a trasformarlo in un vero e proprio protagonismo giudiziario. Al tempo stesso, su tale fenomeno si innestano fattori nuovi, che derivano in parte dai tratti peculiari del diritto penale internazionale, nuovo spazio giuridico di natura ibrida e reticolare, in parte dalla specificità del contesto latinoamericano, reduce da atroci esperienze di criminalità di Stato ed impegnato in un processo di transizione e nella risoluzione dei dilemmi che esso pone.
La necessità di misurarsi con i crimini commessi dai passati regimi dittatoriali e di superare una serie di ostacoli – quali la prescrizione e l’esistenza di disposizioni di amnistia - che impedivano la persecuzione penale dei loro responsabili hanno indotto i giudici latinoamericani a sviluppare dei percorsi argomentativi assai originali. In questo senso, la sussunzione dei fatti nelle fattispecie penali internazionali ha fornito uno strumento essenziale, poiché ad essa consegue l’applicazione del c.d. regime speciale che disciplina tali crimini, e che consente appunto di aggirare gli ostacoli temporali e di natura beneficiale summenzionati. Di conseguenza, gli organi giudiziari hanno maturato differenti percorsi ermeneutici che, mediante un’interpretazione estensiva – al limite della forzatura – degli elementi tipici o delle fonti normative, permettano un ampliamento della portata delle fattispecie penali internazionali e della disciplina loro applicabile. Accanto a questa tendenza interpretativa espansiva se ne manifesta un’altra di segno opposto, che mira a meglio precisare i contorni delle fattispecie penali internazionali o a ridurre le distanze che ancora permangono tra la norma che le tipizza all’interno dei vari ordinamenti nazionali e la corrispondente definizione internazionale, contribuendo in tal modo alla loro progressiva armonizzazione.
L’impatto provocato da queste tendenze giurisprudenziali, più intenso quando proviene dalle Corti Supreme – per effetto della loro speciale autorità persuasiva e, dove prevista, della loro efficacia vincolante -, è destinato a ripercuotersi anche oltre i confini del continente latinoamericano, grazie al fenomeno di circolazione giurisprudenziale e di cross-fertilization, lasciando presagire la formazione di un nuovo ordine mondiale