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On Application of Optimal Control to Intelligent Manufacturing
Get PDFA framework to increase the level of automation of manufacturing processes towards the paradigm of intelligent manufacturing is proposed. The case study considered is the milling of aluminum alloys through a three-axes Computer Numerical Control (CNC) machine tool. The developed controller is called Evaluation and Perception Controller (EPC), and it con- sists of three layers: sensor, perception, and cognitive. A set of sensors displayed in the working volume collect the information necessary to reconstruct the state of the system. In the perception layer the acquired data are processed and learned, thus maintaining updated the models of the process which drive the process optimisation in the cognitive layer.
The Optimal Control Problem (OCP) method is utilised to calculate the controls of the process that optimise a target function, defined accordingly to the specific context in which the operation is executed (namely roughing or finishing). In the general case, the objec- tive function takes into account: productivity, quality, and costs of the process. The material removal rate along the tool path is used as index for process productivity. The quality is quan- tified through measurements of roughness, therefore it is improved by limiting the static and dynamic displacements (i.e. the vibrations) of the tool. The costs of the process here con- sidered are those associated to tooling (i.e. wear of the tool), and energy absorbed by the spindle during on-air free movements.
In order to ensure the feasibility of the solution, algebraic and differential constraints are im- posed on the dynamic response of drives and spindle. The OCP is then solved through an efficient optimisation library developed by the group of Mechatronic Engineering of the Uni- versity of Trento.
The EPC has been designed as a portable system that can be integrated into any CNC ma- chine, once it has been calibrated, and a dedicated communication interface with the NC has been implemented. The tests necessary for the OCP calibration, and requirements for the communication layer between EPC and CN, are described and discussed. Finally, the EPC is tested on real milling processes. The validation of its performances is done by comparing the outcomes of the process with respect to a nominal case, in which the process is set up according to guidelines given by tool manufacturer.
It worth be noted that this work represents not only a step foreword in increasing the level of automation of machining, but rather it proposes an architecture and an approach which can be generalised to several manufacturing processes
From Concepts to Events: a Progressive Process for Multimedia content Analysis
No full textIn this thesis we address the problem of image
and video understanding and specifically, we tackle the problem with machine learning techniques. The primary techniques harnessed in our work are comprised of feature selection, semi-supervised learning, intermediate representation learning and knowledge adaptation.
The final result of this thesis delivers a comprehension of how we can improve multimedia analysis through a variety of machine learning techniques. From the representation perspective, feature selection is potentially helpful. From the classification perspective, semi-supervised learning and transfer learning both bring in reasonable performance by using only few labeled training data
Pena di morte e grazia sovrana nel Regno Lombardo-Veneto (1816-1848)
No full textL’oggetto della tesi – che si inserisce entro la cornice tematica e teorica del dottorato internazionale «Comunicazione politica dall'antichità al XX secolo» – è l’esercizio della pena di morte e l’intervento della grazia sovrana nei processi penali istruiti nel Regno Lombardo-Veneto durante Vormärz (1816-1848).
Alcune considerazioni preliminari hanno fin dal principio orientato la ricerca. Innanzitutto, lo jus aggratiandi va collocato all’interno di una sorta di “campo di tensione”: la potestà di clemenza, in linea teorica, poteva essere arbitrariamente esercitata dall’imperatore, in nome della sua posizione istituzionale che lo riconosceva titolare di tutte le funzioni pubbliche dello Stato, quindi conseguentemente abilitato ad intervenire con atti generali o particolari nell'esercizio di esse; un retaggio, questo, della giustizia di antico regime che si inseriva nel solco di una tradizionale concezione del perdono e, in generale, della risoluzione dei conflitti, fortemente caratterizzata da implicazioni religiose. Allo stesso tempo, tale prerogativa sovrana era tuttavia normata dal codice penale e, come ha rivelato la prassi desumibile dalle fonti giudiziarie, implicitamente ben delimitata.
Secondariamente, l’esercizio della grazia va posto in relazione “biunivoca” con la specificità sociale, politica, istituzionale e giuridica del contesto in cui esso trovava applicazione. Le politiche e le strategie di repressione, punizione e clemenza rispecchiano infatti le modalità attraverso le quali il potere comunica con la società, ma informano anche su come la società comunichi con il potere: una premessa teorica e metodologica che rimanda all'approccio di Mario Sbriccoli, secondo il quale il diritto penale, riflettendo determinati “segni” del contesto sociale e politico in cui viene esercitato, è allo stesso tempo da esso condizionato.
La materia è trattata in una struttura tripartita, ossia nella macrosezioni norma, teoria e prassi. La parte normativa (primo capitolo) è dedicata al percorso e alle istituzioni giudiziarie e politiche attraverso cui si dipanava, secondo il codice criminale del 1803, il processo penale in generale e, nello specifico, i procedimenti conclusisi con sentenza capitale, i quali percorrevano tutta la piramide giudiziaria essendo automaticamente soggetti all'ultima revisione dell'imperatore che poteva confermare la condanna o concedere la grazia. La norma, si vuole sottolineare, non è quindi da intendersi avulsa dall'applicazione pratica del codice: i meccanismi delle istanze e delle revisioni, il concreto margine decisionale dei tribunali lombardo-veneti, specialmente in sede di irrogazione delle condanne capitali e di proposta di grazia, e le competenze dei dicasteri aulici viennesi rispetto all'amministrazione giudiziaria del Regno sono misurabili solo attraverso l'analisi delle centinaia dei fascicoli processuali prodotti nel periodo qui preso in esame. Oltre a ciò, il capitolo inquadra l’importante questione della reintroduzione della pena di morte dopo l’abolizione giuseppina e le norme regolanti il diritto di grazia.
La seconda parte (secondo capitolo) è volta a definire la sistemazione concettuale della grazia e della pena capitale, nonché la “comunicazione giuridica” di tale sistemazione, all'interno del circuito di produzione e diffusione di opere giurisprudenziali nel Regno Lombardo-Veneto, anche in rapporto all'ambito tedesco; allo scopo primario di misurare il livello di intersecazione tra il piano dell’elaborazione teorica e il piano della prassi giudiziaria.
La terza parte dedicata alla prassi, ovvero ai casi concreti di irrogazione delle pene di morte e di commutazione delle stesse in via di grazia, è a sua volta tripartita nei capitoli terzo, quarto e quinto. I primi due capitoli analizzano la frequenza delle sentenze capitali inflitte rispettivamente per delitti comuni e nei processi per alto tradimento, nonché gli orientamenti giuridici e, in senso esteso, politici, secondo i quali esse venivano confermate oppure graziate. Nel quinto capitolo, infine, viene indagata l’attività di un importante istituto in vigore in Lombardia accanto ai tribunali ordinari – del quale non esistono tuttavia testimonianze documentali dirette –, ossia il giudizio statario: una procedura processuale “d’eccezione”, rapida e sommaria, il cui utilizzo era consentito dal codice penale in casi di emergenza sociale
L'ipotesi non necessaria: Ermeneutica demitizzante e critica utilitarista della religione in Jeremy Bentham
No full textTra Paley e Bentham l’utilitarismo attraversò, nel giro di pochi anni, la sua linea d’ombra, e pur mantenendo dei tratti riconoscibili di continuità mutò in modo evidente la propria configurazione e organizzazione teorica. Nella prospettiva della storia di questa peculiare dottrina, lo scoccare di uno dei più importanti momenti di passaggio della modernità si può collocare con una certa precisione, tra il 1785 (l’anno della pubblicazione dei Principles of Moral and Political philosophy di Paley) e il 1789 (l’anno della pubblicazione della Introduction to the principles of Morals and Legislation di Bentham, e che evidentemente è significativo anche per altre clamorose manifestazioni di novità nel mondo istituzionale e politico). Anche in quella peculiare elaborazione collettiva che fu in quel periodo il dibattito che portò alle più importanti prese di posizione pubbliche degli utilitaristi inglesi, si può situare in quegli anni il momento in cui il progressivo “disincanto del mondo” si è fatto concezione generale e sistematica della vita associata degli uomini e del mondo cui essi appartengono. Proprio il passaggio, nel volgere di pochi anni, dall’utilitarismo di Paley a quello di Bentham, comportò – partendo da elementi dottrinali molto simili – una concezione completamente nuova della legittimazione dell’autorità, e una parte rilevante di questo spostamento teorico ed ideologico riguardò questioni apparentemente eterogenee, quali il tema dell’origine del mondo, l’opportunità o meno di prestare giuramento nei tribunali, l’analisi della coerenza logica del catechismo impiegato nell’istruzione religiosa inglese e l’indirizzo esatto della casa di un certo Anania, oscuro abitante della Damasco del primo secolo dopo Cristo
Il mito delle Danaidi, dall'età classica alla paremiografia
No full textLa tesi, prosecuzione del precedente dottorato urbinate, studia il mito delle eroine argive dal commediografo Aristofane fino alle testimonianze a livello ecfrastico del mondo tardoantico. Emerge l' importanza degli antagonisti delle Danaidi
An Effective End-User Development Approach through Domain-Specific Mashups for Research Impact Evaluation
No full textOver the last decade, there has been growing interest in the assessment of the performance of researchers, research groups, universities and even countries. The assessment of productivity is an instrument to select and promote personnel, assign research grants and measure the results of research projects. One particular assessment approach is bibliometrics i.e., the quantitative analysis of scientific publications through citation and content analysis.
However, there is little consensus today on how research evaluation should be performed, and it is commonly acknowledged that the quantitative metrics available today are largely unsatisfactory.
The process is very often highly subjective, and there are no universally accepted criteria.
A number of dierent scientific data sources available on the Web (e.g., DBLP, Microsoft Academic Search, Google Scholar) that are used for such analysis purposes. Taking data from these diverse sources, performing the analysis and visualizing results in different ways is not a trivial and straight forward task. Moreover, the data taken from these sources cannot be used as it is due to the problem of name disambiguation, where many researchers share identical names or an author dierent name variations appear in the data. We believe that the personalization of the evaluation processes is a key element for the appropriate use and practical success of these research impact evaluation tasks. Moreover, people involved in such evaluation processes are not always IT experts and hence not capable to crawl data sources, merge them and compute the needed evaluation procedures.
The recent emergence of mashup tools has refueled research on end-user development, i.e., on enabling end-users without programming skills to produce their own applications. Yet, similar to what happened with analogous promises in web service composition and business process management, research has mostly focused on technology and, as a consequence, has failed its objective. Plain technology (e.g., SOAP/WSDL web services) or simple modeling languages (e.g., Yahoo! Pipes) do not convey enough meaning to non-programmers. We believe that the heart of the problem is that it is impractical to design tools that are generic enough to cover a wide range of application domains, powerful enough to enable the specification of non-trivial logic, and simple enough to be actually accessible to non-programmers. At some point, we need to give up something. In our view, this something is generality since reducing expressive power would mean supporting only the development of toy applications, which is useless, while simplicity is our major aim.
This thesis presents a novel approach for an effective end-user development, specifically for non-programmers. That is, we introduce a domain-specific approach to mashups that "speaks the language of users", i.e., that is aware of the terminology, concepts, rules, and conventions (the domain) the user is comfortable with. We show what developing a domain-specific mashup platform means, which role the mashup meta-model and the domain model play and how these can be merged into a domain-specific mashup metamodel. We illustrate the approach by implementing a generic mashup platform, whose capabilities are based on our proposed mashup meta-model. Further, we illustrate how the generic mashup platform can be tailored for a specific domain, which is achieved through the development of ResEval Mash tool that is specifically developed for the research evaluation domain. Moreover, the thesis proposed an architectural design for mashup platforms, specifically it presents a novel approach for data-intensive mashup-based web applications, which proved to be a substantial contribution. The proposed approach is suitable for those applications, which deal with large amounts of data that travel between client and server.
For the evaluation of our work and to determine the effectiveness and usability of our mashup tool, we performed two separate user studies. The results of the user studies confirm that domain-specific mashup tools indeed lower the entry barrier for non-technical users in mashup development. The methodology presented in this thesis is generic and can be applied for other domains.
Moreover, following the methodological approach the developed mashup platform is also generic, that is, it can be tailored for other domains
Second order nonlinear optical phenomena in strained silicon waveguides
Get PDFA relevant contribution in the explosion of the silicon photonics derives from its nonlinear optics branch, also called nonlinear silicon photonics. This research area exploits the tight confinement of the light, which is allowed by the high contrast index in the silicon sub-micron-structures, and the nonlinearity of silicon to produce (fabricate, develop) novel active devices on the chip scale. Despite of the plenty of third order nonlinear optical phenomena, silicon lacks the second order nonlinearity, which is an essential component of nonlinear optics. In fact, due to the inversion symmetry of its crystalline structure, silicon is characterized by a zero bulk second order nonlinear susceptibility in electric-dipole approximation. Hence, this thesis had the general goal to demonstrate the possibility to perform an all optical experiment of frequency conversion by making use of the second order nonlinear response induced in strained silicon waveguides.
The necessary condition to have a bulk second order nonlinear response in silicon is the breaking of its centrosymmetry. This can be obtained by deforming the crystalline structure, for example, by means of a mechanical strain. Based on this approach, this thesis presents and discusses the results achieved in the characterization of the mechanical properties and the strain-induced second order nonlinearity of silicon-on-insulator (SOI) waveguides mechanically strained by using a stressing cladding layer deposited on the waveguide. In particular, the mechanical characterization has been performed by micro-Raman spectroscopy allowing to reconstruct for the first time the two dimensional spatial distribution of the strain across the waveguide cross-section and study its inhomogeneity by varying the stress applied by the cladding overlayer. The second order nonlinear response and the influence of the strain field on it have been experimentally investigated through Second Harmonic Generation (SHG) experiments in transmission configuration and theoretically analyzed, pointing out the strict dependence of the second order nonlinear susceptibility on the extent and inhomogeneity of the strain field
From materials science to astrophysics with electronic structure calculations
No full textThe first and foremost goal of the present work was to develop novel theoretical and computational methods and use state-of-the-art techniques in electronic structure theory to interpret a specific set of physical problems mainly related, but not limited to, materials science.
Our guiding principle was to relate information obtained from scattering experiments with the numerical solution of the multichannel dynamics of many-body systems, shedding light on the origin of electronic and optical properties of a variety of systems.
The general approach adopted in this thesis was not to present separate chapters for theory, rather we introduced methods along with the experiments.
In particular, we focused on the modeling of both ground and excited states of materials, on vibrational, core and valence electron spectroscopy of condensed matter systems using computational methods at different level of accuracy and complexity to interpret a number of experimental data.
While these methods have been devised for this scope, their applicability, notably the treatment of the continuum states through multichannel scattering formalism, is totally general and can be applied to describe several different experiments, performed with a variety of apparently distant techniques. In particular, the Fano--Fesbach discrete-continuum interaction provides a common framework suitable to this task.
Within this scheme, thus, the calculation of the spectral lineshapes measured by XPS, Auger, NEXAFS, and EEL spectroscopy can be reconciled on the same theoretical grounds with the investigation of the properties of ultra-cold Fermi gases at unitarity, or of the electronic capture and decay rate in ultra-hot plasma found in stellar environments or, finally, with the study of the epitaxial growth of nanostructured materials.
Crossing the borders between several computational, theoretical and experimental techniques, this thesis should be of interest to a broad community, including those interested in aspects of atomic and molecular physics, electronic structure calculations, experimental and theoretical spectroscopy, astrophysics and scattering theorists in a broad sense
ActiveLifestyle: a persuasive platform to monitor and motivate physical training plan compliance in elderly people
No full textThe primary public health goal is to increase the number of years of good health and, therefore, maintain independence and quality of life as long as possible. Healthy ageing is characterized by the avoidance of disease and disability, the maintenance of high physical and cognitive function, and sustained engagement in social and productive activities. These three components together define successful ageing.
An important part of successful ageing, hence, is maximisation of physical performance. The ability to fully participate in productive and recreational activities of daily life may be af-fected when the capacity to easily perform common physical functions decreases. Health status, thus, is an important indicator of quality of life among older people. It appears that especially components of health-related fitness and functional performance, or serious, chronic conditions and diseases that directly influence the components of fitness and performance, are related to perceived health among middle-aged and older adults.
Regular physical activity or exercise substantially prevents the development and progres-sion of most chronic degenerative diseases. In summary, it is evident that to increase older adults’ quality of life and fitness, we need to encourage the elderly to become more physically active and increase their fitness through training.
Home environmental interventions to prevent functional decline seem to be effective and are, furthermore, preferred by elderly. Such interventions with integrated assistive technology devices have, in this context, the potential to further help in overcoming some of the barriers to start training and, thereby, maintaining physical independence for independently living elderly. Hence, the objective of this thesis is to identify how, through IT or IT-mediated persuasive soft-ware applications, we can enable independently living and healthy elderly people to perform balance and strength training plans autonomously at home and keep them motivated, in order to increase their compliance toward the plans
Presence of children and inequality in the household: employment, housework and earnings in European heterosexual couples
No full textThe dissertation investigates couples’ gender inequality in paid and unpaid work as well as in earnings, especially as this inequality relates to parenthood with a cross-national focus.
The different behavior of partnered women and men in the three areas is investigated in different institutional circumstances, focusing on if and how individual and household characteristics are related to within-household gender inequality; then, the extent to which the presence of children is associated with less gender equality in women and men's participation in the work force, division of domestic chores, and relative earnings capacity is investigated; further, I consider how individuals embedded in different contextual and institutional circumstances - in particular referring to welfare regimes, but not only – behave differently in the three areas and whether the contextual traits have a mediating effect on the relation between individual characteristics and women and men's behavior in paid work, unpaid work and relative earning capacity in the presence of children or in the event of a childbirth.
The thesis is made up by six chapters; the first is devoted to a discussion of welfare and gender regimes that are referred to extensively in the literature review and in the empirical chapters. Then I review the main findings in the literature regarding gender differences in paid work, domestic chores and earnings, and their relation with parenthood. From these I draw my hypotheses. In chapter two, I introduce the data and the methods, although a discussion of these is also included in each empirical chapter. Chapters three to five report the analyses and the findings: in chapter three I analyze the relation between paid work and parenthood in four European countries; in chapter four, multi-level models are applied to 23 European states to investigate to what extent the presence of children is associated with the division of domestic chores within couples, and whether the association varies by country; in chapter five, I use multi-level models first and fixed effects panel models afterwards using data from 26 European countries to test, firstly, the association between parenthood and relative earnings of couples, and secondly the effect of child birth on the earnings' balance of couples. Finally, in chapter six I draw some concluding remarks on my findings.
Arguing that gender inequality is rooted in households, the dissertation contributes greater understanding of couple’s intimate household inequality as opposed to merely societal level male-female differences. Focusing on the role of children in promoting gender specialization, the dissertation points to the distinctive circumstances of mothers and fathers, as opposed to women and men (or married women and men) more generally. It elaborates on the role of particular correlates of inequality outcomes, such as education of partners. It works to identify cross-national similarities and differences in the levels of gender inequality as well as in the effects of individual-level predictors