16 resultados para Research through Design

em AMS Tesi di Dottorato - Alm@DL - Università di Bologna


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Although the debate of what data science is has a long history and has not reached a complete consensus yet, Data Science can be summarized as the process of learning from data. Guided by the above vision, this thesis presents two independent data science projects developed in the scope of multidisciplinary applied research. The first part analyzes fluorescence microscopy images typically produced in life science experiments, where the objective is to count how many marked neuronal cells are present in each image. Aiming to automate the task for supporting research in the area, we propose a neural network architecture tuned specifically for this use case, cell ResUnet (c-ResUnet), and discuss the impact of alternative training strategies in overcoming particular challenges of our data. The approach provides good results in terms of both detection and counting, showing performance comparable to the interpretation of human operators. As a meaningful addition, we release the pre-trained model and the Fluorescent Neuronal Cells dataset collecting pixel-level annotations of where neuronal cells are located. In this way, we hope to help future research in the area and foster innovative methodologies for tackling similar problems. The second part deals with the problem of distributed data management in the context of LHC experiments, with a focus on supporting ATLAS operations concerning data transfer failures. In particular, we analyze error messages produced by failed transfers and propose a Machine Learning pipeline that leverages the word2vec language model and K-means clustering. This provides groups of similar errors that are presented to human operators as suggestions of potential issues to investigate. The approach is demonstrated on one full day of data, showing promising ability in understanding the message content and providing meaningful groupings, in line with previously reported incidents by human operators.

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Purpose of this research is to deepen the study on the section in architecture. The survey aims as important elements in the project Teatro Domestico by Aldo Rossi built for the XVII Triennale di Milano in 1986 and, through the implementation on several topics of architecture, verify the timeliness and fertility in the new compositional exercises. Through the study of certain areas of the Rossi’s theory we tried to find a common thread for the reading of the theater project. The theater is the place of the ephemeral and the artificial, which is why his destiny is the end and the fatal loss. The design and construction of theater setting has always had a double meaning between the value of civil architecture and testing of new technologies available. Rossi's experience in this area are clear examples of the inseparable relationship between the representation of architecture as art and design of architecture as a model of reality. In the Teatro Domestico, the distinction between representation and the real world is constantly canceled and returned through the reversal of the meaning and through the skip of scale. At present, studies conducted on the work of Rossi concern the report that the architectural composition is the theory of form, focusing compositional development of a manufacturing process between the typological analysis and form invention. The research, through the analysis of some projects few designs, will try to analyze this issue through the rules of composition both graphical and concrete construction, hoping to decipher the mechanism underlying the invention. The almost total lack of published material on the project Teatro Domestico and the opportunity to visit the archives that preserve the drawings, has allowed the author of this study to deepen the internal issues in the project, thus placing this search as a first step toward possible further analysis on the works of Rossi linked to performance world. The final aim is therefore to produce material that can best describe the work of Rossi. Through the reading of the material published by the same author and the vision of unpublished material preserved in the archives, it was possible to develop new material and increasing knowledge about the work, otherwise difficult to analyze. The research is divided into two groups. The first, taking into account the close relationship most frequently mentioned by Rossi himself between archeology and architectural composition, stresses the importance of tipo such as urban composition reading system as well as open tool of invention. Resuming Ezio Bonfanti’s essay on the work of the architect we wanted to investigate how the paratactic method is applied to the early work conceived and, subsequently as the process reaches a complexity accentuated, while keeping stable the basic terms. Following a brief introduction related to the concept of the section and the different interpretations that over time the term had, we tried to identify with this facility a methodology for reading Rossi’s projects. The result is a constant typological interpretation of the term, not only related to the composition in plant but also through the elevation plans. The section is therefore intended as the overturning of such elevation is marked on the same plane of the terms used, there is a different approach, but a similarity of characters. The identification of architectural phonemes allows comparison with other arts. The research goes in the direction of language trying to identify the relationship between representation and construction, between the ephemeral and the real world. In this sense it will highlight the similarities between the graphic material produced by Ross and some important examples of contemporary author. The comparison between the composition system with the surrealist world of painting and literature will facilitate the understanding and identification of possible rules applied by Rossi. The second part of the research is characterized by a focus on the intent of the project chosen. Teatro Domestico embodies a number of elements that seem to conclude (assuming an end point but also to start) a curriculum author. With it, the experiments carried out on the theater started with the project for the Teatrino Scientifico (1978) through the project for the Teatro del Mondo (1979), into a Laic Tabernacle representative collective and private memory of the city. Starting from a reading of the draft, through the collection of published material, we’ve made an analysis on the explicit themes of the work, finding the conceptual references. Following the taking view of the original materials not published kept at Aldo Rossi's Archive Collection of the Canadian Center for Architecture in Montréal, will be implemented through the existing techniques for digital representation, a virtual reconstruction of the project, adding little to the material, a new element for future studies. The reconstruction is part of a larger research studies where the current technologies of composition and representation in architecture stand side by side with research on the method of composition of this architect. The results achieved are in addition to experiences in the past dealt with the reconstruction of some of the lost works of Aldo Rossi. A partial objective is to reactivate a discourse around this work is considered non-principal, among others born in the prolific activities. Reassessment of development projects which would bring the level of ephemeral works most frequented by giving them the value earned. In conclusion, the research aims to open a new field of interest on the part not only as a technical instrument of representation of an idea but as an actual mechanism through which composition is formed and the idea is developed.

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Can space and place foster child development, and in particular social competence and ecological literacy? If yes, how can space and place do that? This study shows that the answer to the first question is positive and then tries to explain the way space and place can make a difference. The thesis begins with the review of literature from different disciplines – child development and child psychology, education, environmental psychology, architecture and landscape architecture. Some bridges among such disciplines are created and in some cases the ideas from the different areas of research merge: thus, this is an interdisciplinary study. The interdisciplinary knowledge from these disciplines is translated into a range of design suggestions that can foster the development of social competence and ecological literacy. Using scientific knowledge from different disciplines is a way of introducing forms of evidence into the development of design criteria. However, the definition of design criteria also has to pass through the study of a series of school buildings and un-built projects: case studies can give a positive contribution to the criteria because examples and good practices can help “translating” the theoretical knowledge into design ideas and illustrations. To do that, the different case studies have to be assessed in relation to the various themes that emerged in the literature review. Finally, research by design can be used to help define the illustrated design criteria: based on all the background knowledge that has been built, the role of the architect is to provide a series of different design solutions that can give answers to the different “questions” emerged in the literature review.

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La tesi esplora il rapporto tra architettura e acqua, concentrandosi sulle nuove sfide poste dall'innalzamento del livello del mare per i territori marginali come il Basso Ferrarese nel Delta del Po. L'acqua è stata esplorata come elemento fluente e legato alla vita umana attraverso vari aspetti, dall'abitare ai giardini di Barragan, dalle opere di ingegneria romana alle architetture galleggianti. La ricerca ha portato alla creazione di un vocabolario progettuale che comprende relazioni spaziali, funzionali, formali e percettive per sviluppare nuovi scenari futuri. La tesi considera le sfide del cambiamento climatico soprattutto in relazione all’innalzamento del mare, che richiede nuovi approcci progettuali. L'elaborazione di visioni e immaginari utopici, in cui l'acqua diventa materia del progetto, è considerata importante dalla letteratura legata all’ecological urbanism per creare nuovi territori che affrontino le sfide ambientali in modo sostenibile. La ricerca si è concentrata sul Delta del Po e sulla costa adriatica italiana come una delle aree più estese a rischio in Europa. La tesi propone un'immaginario per la composizione futura dello spazio d'acqua che consenta alla persistenza e all'elemento naturale di convivere in armonia. Attraverso esercitazioni progettuali, la ricerca ha esplorato le possibilità compositive dell'area e ha cercato di capire se il sistema di relazioni identificato nella prima fase di ricerca può essere utilizzato per definire nuove possibilità dell'area. In sintesi, la tesi propone nuove riflessioni sul rapporto tra architettura e acqua e suggerisce l'importanza di un approccio sostenibile alle sfide ambientali che devono essere affrontate nei territori marginali. L'immaginario proposto per la composizione futura dello spazio d'acqua si basa su un sistema di relazioni che incoraggia la convivenza dell'uomo con la natura.

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Total ankle arthroplasty (TAA) is still not as satisfactory as total hip and total knee arthroplasty. For the TAA to be considered a valuable alternative to ankle arthrodesis, an effective range of ankle mobility must be recovered. The disappointing clinical results of the current generation of TAA are mostly related to poor understanding of the structures guiding ankle joint mobility. A new design (BOX Ankle) has been developed, uniquely able to restore physiologic ankle mobility and a natural relationship between the implanted components and the retained ligaments. For the first time the shapes of the tibial and talar components in the sagittal plane were designed to be compatible with the demonstrated ligament isometric rotation. This resulted in an unique motion at the replaced ankle where natural sliding as well as rolling motion occurs while at the same time full conformity is maintained between the three components throughout the flexion arc. According to prior research, the design features a spherical convex tibial component, a talar component with radius of curvature in the sagittal plane longer than that of the natural talus, and a fully conforming meniscal component. After computer-based modelling and preliminary observations in several trial implantation in specimens, 126 patients were implanted in the period July 2003 – December 2008. 75 patients with at least 6 months follow-up are here reported. Mean age was 62,6 years (range 22 – 80), mean follow-up 20,2 months. The AOFAS clinical score systems were used to assess patient outcome. Radiographs at maximal dorsiflexion and maximal plantar flexion confirmed the meniscalbearing component moves anteriorly during dorsiflexion and posteriorly during plantarflexion. Frontal and lateral radiographs in the patients, show good alignment of the components, and no signs of radiolucency or loosening. The mean AOFAS score was observed to go from 41 pre-op to 74,6 at 6 month follow-up, with further improvement at the following follow-up. These early results reveal satisfactory clinical scores, with good recovery of range of motion and reduction of pain. Radiographic assessment reveals good osteointegration. All these preliminary results confirm biomechanical studies and the validity of this novel ligamentcompatible prosthesis design. Surely it will be important to re-evaluate these patients later.

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Nel corso del mio lavoro di ricerca mi sono occupata di identificare strategie che permettano il risparmio delle risorse a livello edilizio e di approfondire un metodo per la valutazione ambientale di tali strategie. La convinzione di fondo è che bisogna uscire da una visione antropocentrica in cui tutto ciò che ci circonda è merce e materiale a disposizione dell’uomo, per entrare in una nuova era di equilibrio tra le risorse della terra e le attività che l’uomo esercita sul pianeta. Ho quindi affrontato il tema dell’edilizia responsabile approfondendo l’ambito delle costruzioni in balle di paglia e terra. Sono convinta che l’edilizia industriale abbia un futuro molto breve davanti a sé e lascerà inevitabilmente spazio a tecniche non convenzionali che coinvolgono materiali di semplice reperimento e posa in opera. Sono altresì convinta che il solo utilizzo di materiali naturali non sia garanzia di danni ridotti sull’ecosistema. Allo stesso tempo ritengo che una mera certificazione energetica non sia sinonimo di sostenibilità. Per questo motivo ho valutato le tecnologie non convenzionali con approccio LCA (Life Cycle Assessment), approfondendo gli impatti legati alla produzione, ai trasporti degli stessi, alla tipologia di messa in opera, e ai loro possibili scenari di fine vita. Inoltre ho approfondito il metodo di calcolo dei danni IMPACT, identificando una carenza nel sistema, che non prevede una categoria di danno legata alle modifiche delle condizioni idrogeologiche del terreno. La ricerca si è svolta attraverso attività pratiche e sperimentali in cantieri di edilizia non convenzionale e attività di ricerca e studio sull’LCA presso l’Enea di Bologna (Ing. Paolo Neri).

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The world of communication has changed quickly in the last decade resulting in the the rapid increase in the pace of peoples’ lives. This is due to the explosion of mobile communication and the internet which has now reached all levels of society. With such pressure for access to communication there is increased demand for bandwidth. Photonic technology is the right solution for high speed networks that have to supply wide bandwidth to new communication service providers. In particular this Ph.D. dissertation deals with DWDM optical packet-switched networks. The issue introduces a huge quantity of problems from physical layer up to transport layer. Here this subject is tackled from the network level perspective. The long term solution represented by optical packet switching has been fully explored in this years together with the Network Research Group at the department of Electronics, Computer Science and System of the University of Bologna. Some national as well as international projects supported this research like the Network of Excellence (NoE) e-Photon/ONe, funded by the European Commission in the Sixth Framework Programme and INTREPIDO project (End-to-end Traffic Engineering and Protection for IP over DWDM Optical Networks) funded by the Italian Ministry of Education, University and Scientific Research. Optical packet switching for DWDM networks is studied at single node level as well as at network level. In particular the techniques discussed are thought to be implemented for a long-haul transport network that connects local and metropolitan networks around the world. The main issues faced are contention resolution in a asynchronous variable packet length environment, adaptive routing, wavelength conversion and node architecture. Characteristics that a network must assure as quality of service and resilience are also explored at both node and network level. Results are mainly evaluated via simulation and through analysis.

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The aspartic protease BACE1 (β-amyloid precursor protein cleaving enzyme, β-secretase) is recognized as one of the most promising targets in the treatment of Alzheimer's disease (AD). The accumulation of β-amyloid peptide (Aβ) in the brain is a major factor in the pathogenesis of AD. Aβ is formed by initial cleavage of β-amyloid precursor protein (APP) by β-secretase, therefore BACE1 inhibition represents one of the therapeutic approaches to control progression of AD, by preventing the abnormal generation of Aβ. For this reason, in the last decade, many research efforts have focused at the identification of new BACE1 inhibitors as drug candidates. Generally, BACE1 inhibitors are grouped into two families: substrate-based inhibitors, designed as peptidomimetic inhibitors, and non-peptidomimetic ones. The research on non-peptidomimetic small molecules BACE1 inhibitors remains the most interesting approach, since these compounds hold an improved bioavailability after systemic administration, due to a good blood-brain barrier permeability in comparison to peptidomimetic inhibitors. Very recently, our research group discovered a new promising lead compound for the treatment of AD, named lipocrine, a hybrid derivative between lipoic acid and the AChE inhibitor (AChEI) tacrine, characterized by a tetrahydroacridinic moiety. Lipocrine is one of the first compounds able to inhibit the catalytic activity of AChE and AChE-induced amyloid-β aggregation and to protect against reactive oxygen species. Due to this interesting profile, lipocrine was also evaluated for BACE1 inhibitory activity, resulting in a potent lead compound for BACE1 inhibition. Starting from this interesting profile, a series of tetrahydroacridine analogues were synthesised varying the chain length between the two fragments. Moreover, following the approach of combining in a single molecule two different pharmacophores, we designed and synthesised different compounds bearing the moieties of known AChEIs (rivastigmine and caproctamine) coupled with lipoic acid, since it was shown that dithiolane group is an important structural feature of lipocrine for the optimal inhibition of BACE1. All the tetrahydroacridines, rivastigmine and caproctamine-based compounds, were evaluated for BACE1 inhibitory activity in a FRET (fluorescence resonance energy transfer) enzymatic assay (test A). With the aim to enhancing the biological activity of the lead compound, we applied the molecular simplification approach to design and synthesize novel heterocyclic compounds related to lipocrine, in which the tetrahydroacridine moiety was replaced by 4-amino-quinoline or 4-amino-quinazoline rings. All the synthesized compounds were also evaluated in a modified FRET enzymatic assay (test B), changing the fluorescent substrate for enzymatic BACE1 cleavage. This test method guided deep structure-activity relationships for BACE1 inhibition on the most promising quinazoline-based derivatives. By varying the substituent on the 2-position of the quinazoline ring and by replacing the lipoic acid residue in lateral chain with different moieties (i.e. trans-ferulic acid, a known antioxidant molecule), a series of quinazoline derivatives were obtained. In order to confirm inhibitory activity of the most active compounds, they were evaluated with a third FRET assay (test C) which, surprisingly, did not confirm the previous good activity profiles. An evaluation study of kinetic parameters of the three assays revealed that method C is endowed with the best specificity and enzymatic efficiency. Biological evaluation of the modified 2,4-diamino-quinazoline derivatives measured through the method C, allow to obtain a new lead compound bearing the trans-ferulic acid residue coupled to 2,4-diamino-quinazoline core endowed with a good BACE1 inhibitory activity (IC50 = 0.8 mM). We reported on the variability of the results in the three different FRET assays that are known to have some disadvantages in term of interference rates that are strongly dependent on compound properties. The observed results variability could be also ascribed to different enzyme origin, varied substrate and different fluorescent groups. The inhibitors should be tested on a parallel screening in order to have a more reliable data prior to be tested into cellular assay. With this aim, preliminary cellular BACE1 inhibition assay carried out on lipocrine confirmed a good cellular activity profile (EC50 = 3.7 mM) strengthening the idea to find a small molecule non-peptidomimetic compound as BACE1 inhibitor. In conclusion, the present study allowed to identify a new lead compound endowed with BACE1 inhibitory activity in submicromolar range. Further lead optimization to the obtained derivative is needed in order to obtain a more potent and a selective BACE1 inhibitor based on 2,4-diamino-quinazoline scaffold. A side project related to the synthesis of novel enzymatic inhibitors of BACE1 in order to explore the pseudopeptidic transition-state isosteres chemistry was carried out during research stage at Università de Montrèal (Canada) in Hanessian's group. The aim of this work has been the synthesis of the δ-aminocyclohexane carboxylic acid motif with stereochemically defined substitution to incorporating such a constrained core in potential BACE1 inhibitors. This fragment, endowed with reduced peptidic character, is not known in the context of peptidomimetic design. In particular, we envisioned an alternative route based on an organocatalytic asymmetric conjugate addition of nitroalkanes to cyclohexenone in presence of D-proline and trans-2,5-dimethylpiperazine. The enantioenriched obtained 3-(α-nitroalkyl)-cyclohexanones were further functionalized to give the corresponding δ-nitroalkyl cyclohexane carboxylic acids. These intermediates were elaborated to the target structures 3-(α-aminoalkyl)-1-cyclohexane carboxylic acids in a new readily accessible way.

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Alzheimer's disease (AD) and cancer represent two of the main causes of death worldwide. They are complex multifactorial diseases and several biochemical targets have been recognized to play a fundamental role in their development. Basing on their complex nature, a promising therapeutical approach could be represented by the so-called "Multi-Target-Directed Ligand" approach. This new strategy is based on the assumption that a single molecule could hit several targets responsible for the onset and/or progression of the pathology. In particular in AD, most currently prescribed drugs aim to increase the level of acetylcholine in the brain by inhibiting the enzyme acetylcholinesterase (AChE). However, clinical experience shows that AChE inhibition is a palliative treatment, and the simple modulation of a single target does not address AD aetiology. Research into newer and more potent anti-AD agents is thus focused on compounds whose properties go beyond AChE inhibition (such as inhibition of the enzyme β-secretase and inhibition of the aggregation of beta-amyloid). Therefore, the MTDL strategy seems a more appropriate approach for addressing the complexity of AD and may provide new drugs for tackling its multifactorial nature. In this thesis, it is described the design of new MTDLs able to tackle the multifactorial nature of AD. Such new MTDLs designed are less flexible analogues of Caproctamine, one of the first MTDL owing biological properties useful for the AD treatment. These new compounds are able to inhibit the enzymes AChE, beta-secretase and to inhibit both AChE-induced and self-induced beta-amyloid aggregation. In particular, the most potent compound of the series is able to inhibit AChE in subnanomolar range, to inhibit β-secretase in micromolar concentration and to inhibit both AChE-induced and self-induced beta-amyloid aggregation in micromolar concentration. Cancer, as AD, is a very complex pathology and many different therapeutical approaches are currently use for the treatment of such pathology. However, due to its multifactorial nature the MTDL approach could be, in principle, apply also to this pathology. Aim of this thesis has been the development of new molecules owing different structural motifs able to simultaneously interact with some of the multitude of targets responsible for the pathology. The designed compounds displayed cytotoxic activity in different cancer cell lines. In particular, the most potent compounds of the series have been further evaluated and they were able to bind DNA resulting 100-fold more potent than the reference compound Mitonafide. Furthermore, these compounds were able to trigger apoptosis through caspases activation and to inhibit PIN1 (preliminary result). This last protein is a very promising target because it is overexpressed in many human cancers, it functions as critical catalyst for multiple oncogenic pathways and in several cancer cell lines depletion of PIN1 determines arrest of mitosis followed by apoptosis induction. In conclusion, this study may represent a promising starting pint for the development of new MTDLs hopefully useful for cancer and AD treatment.

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Broad consensus has been reached within the Education and Cognitive Psychology research communities on the need to center the learning process on experimentation and concrete application of knowledge, rather than on a bare transfer of notions. Several advantages arise from this educational approach, ranging from the reinforce of students learning, to the increased opportunity for a student to gain greater insight into the studied topics, up to the possibility for learners to acquire practical skills and long-lasting proficiency. This is especially true in Engineering education, where integrating conceptual knowledge and practical skills assumes a strategic importance. In this scenario, learners are called to play a primary role. They are actively involved in the construction of their own knowledge, instead of passively receiving it. As a result, traditional, teacher-centered learning environments should be replaced by novel learner-centered solutions. Information and Communication Technologies enable the development of innovative solutions that provide suitable answers to the need for the availability of experimentation supports in educational context. Virtual Laboratories, Adaptive Web-Based Educational Systems and Computer-Supported Collaborative Learning environments can significantly foster different learner-centered instructional strategies, offering the opportunity to enhance personalization, individualization and cooperation. More specifically, they allow students to explore different kinds of materials, to access and compare several information sources, to face real or realistic problems and to work on authentic and multi-facet case studies. In addition, they encourage cooperation among peers and provide support through coached and scaffolded activities aimed at fostering reflection and meta-cognitive reasoning. This dissertation will guide readers within this research field, presenting both the theoretical and applicative results of a research aimed at designing an open, flexible, learner-centered virtual lab for supporting students in learning Information Security.

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Two of the main features of today complex software systems like pervasive computing systems and Internet-based applications are distribution and openness. Distribution revolves around three orthogonal dimensions: (i) distribution of control|systems are characterised by several independent computational entities and devices, each representing an autonomous and proactive locus of control; (ii) spatial distribution|entities and devices are physically distributed and connected in a global (such as the Internet) or local network; and (iii) temporal distribution|interacting system components come and go over time, and are not required to be available for interaction at the same time. Openness deals with the heterogeneity and dynamism of system components: complex computational systems are open to the integration of diverse components, heterogeneous in terms of architecture and technology, and are dynamic since they allow components to be updated, added, or removed while the system is running. The engineering of open and distributed computational systems mandates for the adoption of a software infrastructure whose underlying model and technology could provide the required level of uncoupling among system components. This is the main motivation behind current research trends in the area of coordination middleware to exploit tuple-based coordination models in the engineering of complex software systems, since they intrinsically provide coordinated components with communication uncoupling and further details in the references therein. An additional daunting challenge for tuple-based models comes from knowledge-intensive application scenarios, namely, scenarios where most of the activities are based on knowledge in some form|and where knowledge becomes the prominent means by which systems get coordinated. Handling knowledge in tuple-based systems induces problems in terms of syntax - e.g., two tuples containing the same data may not match due to differences in the tuple structure - and (mostly) of semantics|e.g., two tuples representing the same information may not match based on a dierent syntax adopted. Till now, the problem has been faced by exploiting tuple-based coordination within a middleware for knowledge intensive environments: e.g., experiments with tuple-based coordination within a Semantic Web middleware (surveys analogous approaches). However, they appear to be designed to tackle the design of coordination for specic application contexts like Semantic Web and Semantic Web Services, and they result in a rather involved extension of the tuple space model. The main goal of this thesis was to conceive a more general approach to semantic coordination. In particular, it was developed the model and technology of semantic tuple centres. It is adopted the tuple centre model as main coordination abstraction to manage system interactions. A tuple centre can be seen as a programmable tuple space, i.e. an extension of a Linda tuple space, where the behaviour of the tuple space can be programmed so as to react to interaction events. By encapsulating coordination laws within coordination media, tuple centres promote coordination uncoupling among coordinated components. Then, the tuple centre model was semantically enriched: a main design choice in this work was to try not to completely redesign the existing syntactic tuple space model, but rather provide a smooth extension that { although supporting semantic reasoning { keep the simplicity of tuple and tuple matching as easier as possible. By encapsulating the semantic representation of the domain of discourse within coordination media, semantic tuple centres promote semantic uncoupling among coordinated components. The main contributions of the thesis are: (i) the design of the semantic tuple centre model; (ii) the implementation and evaluation of the model based on an existent coordination infrastructure; (iii) a view of the application scenarios in which semantic tuple centres seem to be suitable as coordination media.

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The "sustainability" concept relates to the prolonging of human economic systems with as little detrimental impact on ecological systems as possible. Construction that exhibits good environmental stewardship and practices that conserve resources in a manner that allow growth and development to be sustained for the long-term without degrading the environment are indispensable in a developed society. Past, current and future advancements in asphalt as an environmentally sustainable paving material are especially important because the quantities of asphalt used annually in Europe as well as in the U.S. are large. The asphalt industry is still developing technological improvements that will reduce the environmental impact without affecting the final mechanical performance. Warm mix asphalt (WMA) is a type of asphalt mix requiring lower production temperatures compared to hot mix asphalt (HMA), while aiming to maintain the desired post construction properties of traditional HMA. Lowering the production temperature reduce the fuel usage and the production of emissions therefore and that improve conditions for workers and supports the sustainable development. Even the crumb-rubber modifier (CRM), with shredded automobile tires and used in the United States since the mid 1980s, has proven to be an environmentally friendly alternative to conventional asphalt pavement. Furthermore, the use of waste tires is not only relevant in an environmental aspect but also for the engineering properties of asphalt [Pennisi E., 1992]. This research project is aimed to demonstrate the dual value of these Asphalt Mixes in regards to the environmental and mechanical performance and to suggest a low environmental impact design procedure. In fact, the use of eco-friendly materials is the first phase towards an eco-compatible design but it cannot be the only step. The eco-compatible approach should be extended also to the design method and material characterization because only with these phases is it possible to exploit the maximum potential properties of the used materials. Appropriate asphalt concrete characterization is essential and vital for realistic performance prediction of asphalt concrete pavements. Volumetric (Mix design) and mechanical (Permanent deformation and Fatigue performance) properties are important factors to consider. Moreover, an advanced and efficient design method is necessary in order to correctly use the material. A design method such as a Mechanistic-Empirical approach, consisting of a structural model capable of predicting the state of stresses and strains within the pavement structure under the different traffic and environmental conditions, was the application of choice. In particular this study focus on the CalME and its Incremental-Recursive (I-R) procedure, based on damage models for fatigue and permanent shear strain related to the surface cracking and to the rutting respectively. It works in increments of time and, using the output from one increment, recursively, as input to the next increment, predicts the pavement conditions in terms of layer moduli, fatigue cracking, rutting and roughness. This software procedure was adopted in order to verify the mechanical properties of the study mixes and the reciprocal relationship between surface layer and pavement structure in terms of fatigue and permanent deformation with defined traffic and environmental conditions. The asphalt mixes studied were used in a pavement structure as surface layer of 60 mm thickness. The performance of the pavement was compared to the performance of the same pavement structure where different kinds of asphalt concrete were used as surface layer. In comparison to a conventional asphalt concrete, three eco-friendly materials, two warm mix asphalt and a rubberized asphalt concrete, were analyzed. The First Two Chapters summarize the necessary steps aimed to satisfy the sustainable pavement design procedure. In Chapter I the problem of asphalt pavement eco-compatible design was introduced. The low environmental impact materials such as the Warm Mix Asphalt and the Rubberized Asphalt Concrete were described in detail. In addition the value of a rational asphalt pavement design method was discussed. Chapter II underlines the importance of a deep laboratory characterization based on appropriate materials selection and performance evaluation. In Chapter III, CalME is introduced trough a specific explanation of the different equipped design approaches and specifically explaining the I-R procedure. In Chapter IV, the experimental program is presented with a explanation of test laboratory devices adopted. The Fatigue and Rutting performances of the study mixes are shown respectively in Chapter V and VI. Through these laboratory test data the CalME I-R models parameters for Master Curve, fatigue damage and permanent shear strain were evaluated. Lastly, in Chapter VII, the results of the asphalt pavement structures simulations with different surface layers were reported. For each pavement structure, the total surface cracking, the total rutting, the fatigue damage and the rutting depth in each bound layer were analyzed.

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Design parameters, process flows, electro-thermal-fluidic simulations and experimental characterizations of Micro-Electro-Mechanical-Systems (MEMS) suited for gas-chromatographic (GC) applications are presented and thoroughly described in this thesis, whose topic belongs to the research activities the Institute for Microelectronics and Microsystems (IMM)-Bologna is involved since several years, i.e. the development of micro-systems for chemical analysis, based on silicon micro-machining techniques and able to perform analysis of complex gaseous mixtures, especially in the field of environmental monitoring. In this regard, attention has been focused on the development of micro-fabricated devices to be employed in a portable mini-GC system for the analysis of aromatic Volatile Organic Compounds (VOC) like Benzene, Toluene, Ethyl-benzene and Xylene (BTEX), i.e. chemical compounds which can significantly affect environment and human health because of their demonstrated carcinogenicity (benzene) or toxicity (toluene, xylene) even at parts per billion (ppb) concentrations. The most significant results achieved through the laboratory functional characterization of the mini-GC system have been reported, together with in-field analysis results carried out in a station of the Bologna air monitoring network and compared with those provided by a commercial GC system. The development of more advanced prototypes of micro-fabricated devices specifically suited for FAST-GC have been also presented (silicon capillary columns, Ultra-Low-Power (ULP) Metal OXide (MOX) sensor, Thermal Conductivity Detector (TCD)), together with the technological processes for their fabrication. The experimentally demonstrated very high sensitivity of ULP-MOX sensors to VOCs, coupled with the extremely low power consumption, makes the developed ULP-MOX sensor the most performing metal oxide sensor reported up to now in literature, while preliminary test results proved that the developed silicon capillary columns are capable of performances comparable to those of the best fused silica capillary columns. Finally, the development and the validation of a coupled electro-thermal Finite Element Model suited for both steady-state and transient analysis of the micro-devices has been described, and subsequently implemented with a fluidic part to investigate devices behaviour in presence of a gas flowing with certain volumetric flow rates.

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The thesis aims at analysing the role of collective action as a viable alternative to the traditional forms of intervention in agriculture in order to encourage the provision of agri-environmental public goods. Which are the main benefits of collective action, in terms of effectiveness and efficiency, compared to traditional market or public intervention policies? What are the drivers that encourage farmers to participate into collective action? To what extent it is possible to incorporate collective aspects into policies aimed at providing agri-environmental public goods? With the objective of addressing these research questions, the thesis is articulated in two levels: a theoretical analysis on the role of collective action in the provision of public goods and a specific investigation of two local initiative,s were an approach collective management of agro-environmental resources was successfully implemented. The first case study concerns a project named “Custodians of the Territory”, developed by the local agency in Tuscany “Comunità Montana Media Valle del Serchio”, which settled for an agreement with local farmers for a collective provision of environmental services related to the hydro-geological management of the district. The second case study is related to the territorial agri-environmental agreement experimented in Valdaso (Marche), where local farmers have adopted integrated pest management practices collectively with the aim of reducing the environmental impact of their farming practices. The analysis of these initiatives, carried out through participatory methods (Rapid Rural Appraisal), allowed developing a theoretical discussion on the role of innovative tools (such as co-production and co-management) in the provision of agri-environmental public goods. The case studies also provided some recommendations on the government intervention and policies needed to promote successful collective action for the provision of agri-environmental public goods.

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Fibre-Reinforced-Plastics are composite materials composed by thin fibres with high mechanical properties, made to work together with a cohesive plastic matrix. The huge advantages of fibre reinforced plastics over traditional materials are their high specific mechanical properties i.e. high stiffness and strength to weight ratios. This kind of composite materials is the most disruptive innovation in the structural materials field seen in recent years and the areas of potential application are still many. However, there are few aspects which limit their growth: on the one hand the information available about their properties and long term behaviour is still scarce, especially if compared with traditional materials for which there has been developed an extended database through years of use and research. On the other hand, the technologies of production are still not as developed as the ones available to form plastics, metals and other traditional materials. A third aspect is that the new properties presented by these materials e.g. their anisotropy, difficult the design of components. This thesis will provide several case-studies with advancements regarding the three limitations mentioned. In particular, the long term mechanical properties have been studied through an experimental analysis of the impact of seawater on GFRP. Regarding production methods, the pre-impregnated cured in autoclave process was considered: a rapid tooling method to produce moulds will be presented, and a study about the production of thick components. Also, two liquid composite moulding methods will be presented, with a case-study regarding a large component with sandwich structure that was produced with the Vacuum-Assisted-Resin-Infusion method, and a case-study regarding a thick con-rod beam that was produced with the Resin-Transfer-Moulding process. The final case-study will analyse the loads acting during the use of a particular sportive component, made with FRP layers and a sandwich structure, practical design rules will be provided.