254 resultados para acque, Marecchia, tecniche analitiche, nitrati


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Le soluzioni tecnologiche rese oggi disponibili dalle discipline della moderna Geomatica, offrono opportunità di grande interesse per il rilevamento nel settore dei Beni Culturali, sia per quanto riguarda il momento primario del rilievo, cioè la fase di acquisizione del dato metrico, sia per quanto concerne la questione della rappresentazione per oggetti di interesse archeologico, artistico, architettonico. Lo studio oggetto della presente tesi si propone, sulla base di numerose esperienze maturate nel corso del Dottorato dal Laboratorio di Topografia e Fotogrammetria del DISTART, di affrontare e approfondire le problematiche connesse all’utilizzo della fotogrammetria digitale e del laser a scansione terrestre per applicazioni nell’ambito dei Beni Culturali. La ricerca condotta è prettamente applicata, quindi è stata primaria l’esigenza di avere a disposizione reali casi di studio su cui sperimentare le tecniche di interesse; è però importante sottolineare che questo è un campo in cui ogni esperienza presenta proprie caratteristiche e peculiarità che la rendono interessante e difficilmente descrivibile con schemi convenzionali e metodologie standardizzate, quindi le problematiche emerse hanno di volta in volta indirizzato e spinto la ricerca all’approfondimento di certi aspetti piuttosto che altri. A tal proposito è stato evidenziato dalle esperienze effettuate che il campo dei Beni Culturali è forse il più emblematico delle potenzialità rese oggi disponibili dalle moderne tecnologie della Geomatica, e soprattutto dalle possibilità offerte da un approccio integrato e multi – disciplinare di tecniche e tecnologie diverse; per questo nell’Introduzione si è voluto sottolineare questo aspetto, descrivendo l’approccio metodologico adottato in molti lavori in contesto archeologico, che include generalmente diverse tecniche integrate tra loro allo scopo di realizzare in modo veloce e rigoroso un rilievo multi – scala che parte dal territorio, passa attraverso l’area del sito archeologico e degli scavi, ed arriva fino al singolo reperto; questo approccio è caratterizzato dall’avere tutti i dati e risultati in un unico e ben definito sistema di riferimento. In questa chiave di lettura l’attenzione si è poi focalizzata sulle due tecniche che rivestono oggi nel settore in esame il maggiore interesse, cioè fotogrammetria digitale e laser a scansione terrestre. La struttura della tesi segue le fasi classiche del processo che a partire dal rilievo porta alla generazione dei prodotti di rappresentazione; i primi due capitoli, incentrati sull’acquisizione del dato metrico, riguardano quindi da un lato le caratteristiche delle immagini e dei sensori digitali, dall’altro le diverse tipologie di sistemi laser con le corrispondenti specifiche tecniche; sempre nei primi capitoli vengono descritte le caratteristiche metodologiche e tecnico – operative e le relative problematiche delle due tipologie di rilievo. Segue un capitolo sulle procedure di calibrazione delle camere digitali non professionali, imperniato sull’utilizzo di software diversi, commerciali e sviluppati in house per questo scopo, prestando attenzione anche agli strumenti che essi offrono in termini di risultati ottenibili e di controllo statistico sugli stessi. La parte finale della tesi è dedicata al problema della rappresentazione, con l’obiettivo di presentare un quadro generale delle possibilità offerte dalle moderne tecnologie: raddrizzamenti, ortofoto, ortofoto di precisione e infine modelli tridimensionali foto – realistici, generati a partire sia da dati fotogrammetrici sia da dati laser.

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This research investigated someone of the main problems connected to the application of Tissue Engineering in the prosthetic field, in particular about the characterization of the scaffolding materials and biomimetic strategies adopted in order to promote the implant integration. The spectroscopic and thermal analysis techniques were usefully applied to characterize the chemico-physical properties of the materials such as – crystallinity; – relative composition in case of composite materials; – Structure and conformation of polymeric and peptidic chains; – mechanism and degradation rate; – Intramolecular and intermolecular interactions (hydrogen bonds, aliphatic interactions). This kind of information are of great importance in the comprehension of the interactions that scaffold undergoes when it is in contact with biological tissues; this information are fundamental to predict biodegradation mechanisms and to understand how chemico-physical properties change during the degradation process. In order to fully characterize biomaterials, this findings must be integrated by information relative to mechanical aspects and in vitro and in vivo behavior thanks to collaborations with biomedical engineers and biologists. This study was focussed on three different systems that correspond to three different strategies adopted in Tissue Engineering: biomimetic replica of fibrous 3-D structure of extracellular matrix (PCL-PLLA), incorporation of an apatitic phase similar to bone inorganic phase to promote biomineralization (PCL-HA), surface modification with synthetic oligopeptides that elicit the interaction with osteoblasts. The characterization of the PCL-PLLA composite underlined that the degradation started along PLLA fibres, which are more hydrophylic, and they serve as a guide for tissue regeneration. Moreover it was found that some cellular lines are more active in the colonization of the scaffold. In the PCL-HA composite, the weight ratio between the polymeric and the inorganic phase plays an essential role both in the degradation process and in the biomineralization of the material. The study of self-assembling peptides allowed to clarify the influence of primary structure on intermolecular and intermolecular interactions, that lead to the formation of the secondary structure and it was possible to find a new class of oligopeptides useful to functionalize materials surface. Among the analytical techniques used in this study, Raman vibrational spectroscopy played a major role, being non-destructive and non-invasive, two properties that make it suitable to degradation studies and to morphological characterization. Also micro-IR spectroscopy was useful in the comprehension of peptide structure on oxidized titanium: up to date this study was one of the first to employ this relatively new technique in the biomedical field.

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Providing support for multimedia applications on low-power mobile devices remains a significant research challenge. This is primarily due to two reasons: • Portable mobile devices have modest sizes and weights, and therefore inadequate resources, low CPU processing power, reduced display capabilities, limited memory and battery lifetimes as compared to desktop and laptop systems. • On the other hand, multimedia applications tend to have distinctive QoS and processing requirementswhichmake themextremely resource-demanding. This innate conflict introduces key research challenges in the design of multimedia applications and device-level power optimization. Energy efficiency in this kind of platforms can be achieved only via a synergistic hardware and software approach. In fact, while System-on-Chips are more and more programmable thus providing functional flexibility, hardwareonly power reduction techniques cannot maintain consumption under acceptable bounds. It is well understood both in research and industry that system configuration andmanagement cannot be controlled efficiently only relying on low-level firmware and hardware drivers. In fact, at this level there is lack of information about user application activity and consequently about the impact of power management decision on QoS. Even though operating system support and integration is a requirement for effective performance and energy management, more effective and QoSsensitive power management is possible if power awareness and hardware configuration control strategies are tightly integratedwith domain-specificmiddleware services. The main objective of this PhD research has been the exploration and the integration of amiddleware-centric energymanagement with applications and operating-system. We choose to focus on the CPU-memory and the video subsystems, since they are the most power-hungry components of an embedded system. A second main objective has been the definition and implementation of software facilities (like toolkits, API, and run-time engines) in order to improve programmability and performance efficiency of such platforms. Enhancing energy efficiency and programmability ofmodernMulti-Processor System-on-Chips (MPSoCs) Consumer applications are characterized by tight time-to-market constraints and extreme cost sensitivity. The software that runs on modern embedded systems must be high performance, real time, and even more important low power. Although much progress has been made on these problems, much remains to be done. Multi-processor System-on-Chip (MPSoC) are increasingly popular platforms for high performance embedded applications. This leads to interesting challenges in software development since efficient software development is a major issue for MPSoc designers. An important step in deploying applications on multiprocessors is to allocate and schedule concurrent tasks to the processing and communication resources of the platform. The problem of allocating and scheduling precedenceconstrained tasks on processors in a distributed real-time system is NP-hard. There is a clear need for deployment technology that addresses thesemulti processing issues. This problem can be tackled by means of specific middleware which takes care of allocating and scheduling tasks on the different processing elements and which tries also to optimize the power consumption of the entire multiprocessor platform. This dissertation is an attempt to develop insight into efficient, flexible and optimalmethods for allocating and scheduling concurrent applications tomultiprocessor architectures. It is a well-known problem in literature: this kind of optimization problems are very complex even in much simplified variants, therefore most authors propose simplified models and heuristic approaches to solve it in reasonable time. Model simplification is often achieved by abstracting away platform implementation ”details”. As a result, optimization problems become more tractable, even reaching polynomial time complexity. Unfortunately, this approach creates an abstraction gap between the optimization model and the real HW-SW platform. The main issue with heuristic or, more in general, with incomplete search is that they introduce an optimality gap of unknown size. They provide very limited or no information on the distance between the best computed solution and the optimal one. The goal of this work is to address both abstraction and optimality gaps, formulating accurate models which accounts for a number of ”non-idealities” in real-life hardware platforms, developing novel mapping algorithms that deterministically find optimal solutions, and implementing software infrastructures required by developers to deploy applications for the targetMPSoC platforms. Energy Efficient LCDBacklightAutoregulation on Real-LifeMultimediaAp- plication Processor Despite the ever increasing advances in Liquid Crystal Display’s (LCD) technology, their power consumption is still one of the major limitations to the battery life of mobile appliances such as smart phones, portable media players, gaming and navigation devices. There is a clear trend towards the increase of LCD size to exploit the multimedia capabilities of portable devices that can receive and render high definition video and pictures. Multimedia applications running on these devices require LCD screen sizes of 2.2 to 3.5 inches andmore to display video sequences and pictures with the required quality. LCD power consumption is dependent on the backlight and pixel matrix driving circuits and is typically proportional to the panel area. As a result, the contribution is also likely to be considerable in future mobile appliances. To address this issue, companies are proposing low power technologies suitable for mobile applications supporting low power states and image control techniques. On the research side, several power saving schemes and algorithms can be found in literature. Some of them exploit software-only techniques to change the image content to reduce the power associated with the crystal polarization, some others are aimed at decreasing the backlight level while compensating the luminance reduction by compensating the user perceived quality degradation using pixel-by-pixel image processing algorithms. The major limitation of these techniques is that they rely on the CPU to perform pixel-based manipulations and their impact on CPU utilization and power consumption has not been assessed. This PhDdissertation shows an alternative approach that exploits in a smart and efficient way the hardware image processing unit almost integrated in every current multimedia application processors to implement a hardware assisted image compensation that allows dynamic scaling of the backlight with a negligible impact on QoS. The proposed approach overcomes CPU-intensive techniques by saving system power without requiring either a dedicated display technology or hardware modification. Thesis Overview The remainder of the thesis is organized as follows. The first part is focused on enhancing energy efficiency and programmability of modern Multi-Processor System-on-Chips (MPSoCs). Chapter 2 gives an overview about architectural trends in embedded systems, illustrating the principal features of new technologies and the key challenges still open. Chapter 3 presents a QoS-driven methodology for optimal allocation and frequency selection for MPSoCs. The methodology is based on functional simulation and full system power estimation. Chapter 4 targets allocation and scheduling of pipelined stream-oriented applications on top of distributed memory architectures with messaging support. We tackled the complexity of the problem by means of decomposition and no-good generation, and prove the increased computational efficiency of this approach with respect to traditional ones. Chapter 5 presents a cooperative framework to solve the allocation, scheduling and voltage/frequency selection problem to optimality for energyefficient MPSoCs, while in Chapter 6 applications with conditional task graph are taken into account. Finally Chapter 7 proposes a complete framework, called Cellflow, to help programmers in efficient software implementation on a real architecture, the Cell Broadband Engine processor. The second part is focused on energy efficient software techniques for LCD displays. Chapter 8 gives an overview about portable device display technologies, illustrating the principal features of LCD video systems and the key challenges still open. Chapter 9 shows several energy efficient software techniques present in literature, while Chapter 10 illustrates in details our method for saving significant power in an LCD panel. Finally, conclusions are drawn, reporting the main research contributions that have been discussed throughout this dissertation.

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Human biomonitoring (HBM) is an ideal tool for evaluating toxicant exposure in health risk assessment. Chemical substances or their metabolites related to environmental pollutants can be detected as biomarkers of exposure using a wide variety of biological fluids. Individual exposure to aromatic hydrocarbon compounds (benzene, toluene, and o-xylene –“BTX”) were analysed with a liquid chromatography coupled to electrospray ionisation-mass spectrometry (μHPLC-ESI-MS/MS) method for the simultaneous quantitative detection of the BTX exposure biomarker SPMA, SBMA and o-MBMA in human urine. Urinary S-phenylmercapturic acid (SPMA) is a biomarker proposed by the American Conference of Governmental Industrial Hygienists (ACGIH) for assessing occupational exposure to benzene (Biological Exposure Index of 25 microg/g creatinine). Urinary S-benzylmercapturic (SBMA) and o-methyl S-benzyl mercapturic acid (o-MBMA) are specific toluene and o-xylene metabolites of glutathione detoxicant pathways, proposed as reliable biomarkers of exposure. To this aim a pre-treatment of the urine with solid phase extraction (SPE) and an evaporation step were necessary to concentrate the mercapturic acids before instrumental analysis. A liquid chromatography separation was carried out with a reversed phase capillary column (Synergi 4u Max-RP) using a binary gradient composed of an acquous solution of formic acid 0.07% v/v and methanol. The mercapturic acids were determinated by negative-ion-mass spectrometry and the data were corrected using isotope-labelled analogs as internal standards. The analytical method follows U.S. Food and Drug Administration guidance and was applied to assess exposure to BTX in a group of 396 traffic wardens. The association between biomarker results and individual factors, such as age, sex and tobacco smoke were also investigated. The present work also included improvements in the methods used by modifying various chromatographic parameters and experimental procedures. A partial validation was conducted to evaluate LOD, precision, accuracy, recovery as well as matrix effects. Higher sensitivity will be possible in future biological monitoring programmes, allowing evaluation of very low level of BTX human exposure. Keywords: Human biomonitoring, aromatic hydrocarbons, biomarker of exposure, HPLC-MS/MS.

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The species of the genus Coenosia Meigen are polyphagous predators both in the larval and in the adult stage. In Europe five Coenosia species of the ‘tigrina group’ are naturally present in greenhouses, where they can establish for long periods. As their wide preys range includes important pests of protected crops, as Aleyrodidae, Sciaridae and Agromyzidae, Coenosia species are considered promising potential biological control agents. A method for rearing Coenosia species in vivo was developed for the first time in 1993 in Germany, where C. attenuata, C. strigipes and C. humilis were bred on Bradysia paupera (Diptera Sciaridae), reared on Fusarium spp. cultivated on wood fibre. Although this method was partially simplified afterwards, it is still too complex and expensive for a mass production. This research aimed at simplifying this rearing procedure and making it cheaper, in the perspective of an eventual mass production. Studies on potential preys were conducted, to determine their suitability for C. attenuata larvae and adults and to develop rearing methods. Biology and rearing methods of Bradysia paupera Tuomikoski, Scatella stagnalis Fallén and Drosophila melanogaster Meigen (Diptera: Sciaridae, Ephydridae, Drosophilidae) were compared. B. paupera resulted the most suitable prey for rearing C. attenuata in vivo. The Sciarid fly was effectively reared on damp coconut fibre with fresh Agaricus bisporus (J.E. Lange) Pilát, thus simplifying the existing method. After preliminary trials with different potential preys, attempts to rear C. attenuata in vivo on B. paupera and D. melanogaster were made. The best results were obtained with B. paupera, reared on coconut fibre and A. bisporus, but the method needs further improvement. Trials of in vitro rearing of C. attenuata were also made: as no specific diet for Coenosia species is reported in literature, different potentially suitable media were tested. Among these, a specific diet for Diptera Tachinidae resulted a good starting point for further studies and improvements. The biology of C. attenuata adults captured in greenhouses was also studied, by observing both groups and isolated individuals. Data on lifespan, daily number of preys per adult, daily number of laid eggs and hatching rate were recorded, and the effects of different foods on these parameters were analyzed. The following foods were compared: D. melanogaster adults only, as preys for C. attenuata; D. melanogaster adults and a water-honey solution; the water-honey solution only. Honey resulted an effective food integration for C. attenuata, increasing lifespan and the number of egg laying females. It is possible that in greenhouses Coenosia adults complete the preys diet with nectar and/or honeydew. Moreover, the integration with honey reduced the daily preys consumption. This may allow to prevent cannibalism among Coenosia adults in the rearing conditions, where high population densities are required. A survey of the Coenosia species naturally present in Lombardy greenhouses was conducted. The species C. attenuata, C. strigipes, C. tigrina and C. atra were detected. C. attenuata resulted the most common, recorded in most greenhouses and for consecutive years. Besides, the presence of potential preys, weeds and the crops were recorded in each greenhouse. Nevertheless, it is difficult to determine the relation between these parameters and the presence of Coenosia species.

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La studio della distribuzione spaziale e temporale della associazioni a foraminiferi planctonici, campionati in zone con differente regime idrografico, ha permesso di comprendere che molte specie possono essere diagnostiche della presenza di diverse masse d’acqua superficiali e sottosuperficiali e di diversi regimi di nutrienti nelle acque oceaniche. Parte di questo lavoro di tesi si basa sullo studio delle associazioni a foraminiferi planctonici attualmente viventi nel Settore Pacifico dell’Oceano Meridionale (Mare di Ross e Zona del Fronte Polare) e nel Mare Mediterraneo (Mar Tirreno Meridionale). L’obiettivo di questo studio è quello di comprendere i fattori (temperatura, salinità, nutrienti etc.) che determinano la distribuzione attuale delle diverse specie al fine di valutarne il valore di “indicatori” (proxies) utili alla ricostruzione degli scenari paleoclimatici e paleoceanografici succedutisi in queste aree. I risultati documentano che la distribuzione delle diverse specie, il numero di individui e le variazioni nella morfologia di alcuni taxa sono correlate alle caratteristiche chimico-fisiche della colonna e alla disponibilità di nutrienti e di clorofilla. La seconda parte del lavoro di tesi ha previsto l’analisi degli isotopi stabili dell’ossigeno e del rapporto Mg/Ca in gusci di N. pachyderma (sin) prelevati da pescate di micro zooplancton (per tarare l’equazione di paleo temperatura) da un box core e da una carota provenienti dalla zona del Fronte Polare (Oceano Pacifico meridionale), al fine di ricostruire le variazioni di temperatura negli ultimi 13 ka e durante la Mid-Pleistocene Revolution. Le temperature, dedotte tramite i valori degli isotopi stabili dell’ossigeno, sono coerenti con le temperature attuali documentate in questa zona e il trend di temperatura è paragonabile a quelli riportati in letteratura anche per eventi climatici come lo Younger Dryas e il mid-Holocene Optimum. I valori del rapporto Mg/Ca misurato tramite due diverse tecniche di analisi (laser ablation e analisi in soluzione) sono risultati sempre molto più alti dei valori riportati in letteratura per la stessa specie. La laser ablation sembra carente dal punto di vista del cleaning del campione e da questo studio emerge che le due tecniche non sono comparabili e che non possono essere usate indifferentemente sullo stesso campione. Per quanto riguarda l’analisi dei campioni in soluzione è stato migliorato il protocollo di cleaning per il trattamento di campioni antartici, che ha permesso di ottenere valori veritieri e utili ai fini delle ricostruzioni di paleotemperatura. Tuttavia, rimane verosimile l’ipotesi che in ambienti particolari come questo, con salinità e temperature molto basse, l’incorporazione del Mg all’interno del guscio risenta delle condizioni particolari e che non segua quindi la relazione esponenziale con la temperatura ampiamente dimostrata ad altre latitudini.

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Ambient Intelligence (AmI) envisions a world where smart, electronic environments are aware and responsive to their context. People moving into these settings engage many computational devices and systems simultaneously even if they are not aware of their presence. AmI stems from the convergence of three key technologies: ubiquitous computing, ubiquitous communication and natural interfaces. The dependence on a large amount of fixed and mobile sensors embedded into the environment makes of Wireless Sensor Networks one of the most relevant enabling technologies for AmI. WSN are complex systems made up of a number of sensor nodes, simple devices that typically embed a low power computational unit (microcontrollers, FPGAs etc.), a wireless communication unit, one or more sensors and a some form of energy supply (either batteries or energy scavenger modules). Low-cost, low-computational power, low energy consumption and small size are characteristics that must be taken into consideration when designing and dealing with WSNs. In order to handle the large amount of data generated by a WSN several multi sensor data fusion techniques have been developed. The aim of multisensor data fusion is to combine data to achieve better accuracy and inferences than could be achieved by the use of a single sensor alone. In this dissertation we present our results in building several AmI applications suitable for a WSN implementation. The work can be divided into two main areas: Multimodal Surveillance and Activity Recognition. Novel techniques to handle data from a network of low-cost, low-power Pyroelectric InfraRed (PIR) sensors are presented. Such techniques allow the detection of the number of people moving in the environment, their direction of movement and their position. We discuss how a mesh of PIR sensors can be integrated with a video surveillance system to increase its performance in people tracking. Furthermore we embed a PIR sensor within the design of a Wireless Video Sensor Node (WVSN) to extend its lifetime. Activity recognition is a fundamental block in natural interfaces. A challenging objective is to design an activity recognition system that is able to exploit a redundant but unreliable WSN. We present our activity in building a novel activity recognition architecture for such a dynamic system. The architecture has a hierarchical structure where simple nodes performs gesture classification and a high level meta classifiers fuses a changing number of classifier outputs. We demonstrate the benefit of such architecture in terms of increased recognition performance, and fault and noise robustness. Furthermore we show how we can extend network lifetime by performing a performance-power trade-off. Smart objects can enhance user experience within smart environments. We present our work in extending the capabilities of the Smart Micrel Cube (SMCube), a smart object used as tangible interface within a tangible computing framework, through the development of a gesture recognition algorithm suitable for this limited computational power device. Finally the development of activity recognition techniques can greatly benefit from the availability of shared dataset. We report our experience in building a dataset for activity recognition. Such dataset is freely available to the scientific community for research purposes and can be used as a testbench for developing, testing and comparing different activity recognition techniques.

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The digital electronic market development is founded on the continuous reduction of the transistors size, to reduce area, power, cost and increase the computational performance of integrated circuits. This trend, known as technology scaling, is approaching the nanometer size. The lithographic process in the manufacturing stage is increasing its uncertainty with the scaling down of the transistors size, resulting in a larger parameter variation in future technology generations. Furthermore, the exponential relationship between the leakage current and the threshold voltage, is limiting the threshold and supply voltages scaling, increasing the power density and creating local thermal issues, such as hot spots, thermal runaway and thermal cycles. In addiction, the introduction of new materials and the smaller devices dimension are reducing transistors robustness, that combined with high temperature and frequently thermal cycles, are speeding up wear out processes. Those effects are no longer addressable only at the process level. Consequently the deep sub-micron devices will require solutions which will imply several design levels, as system and logic, and new approaches called Design For Manufacturability (DFM) and Design For Reliability. The purpose of the above approaches is to bring in the early design stages the awareness of the device reliability and manufacturability, in order to introduce logic and system able to cope with the yield and reliability loss. The ITRS roadmap suggests the following research steps to integrate the design for manufacturability and reliability in the standard CAD automated design flow: i) The implementation of new analysis algorithms able to predict the system thermal behavior with the impact to the power and speed performances. ii) High level wear out models able to predict the mean time to failure of the system (MTTF). iii) Statistical performance analysis able to predict the impact of the process variation, both random and systematic. The new analysis tools have to be developed beside new logic and system strategies to cope with the future challenges, as for instance: i) Thermal management strategy that increase the reliability and life time of the devices acting to some tunable parameter,such as supply voltage or body bias. ii) Error detection logic able to interact with compensation techniques as Adaptive Supply Voltage ASV, Adaptive Body Bias ABB and error recovering, in order to increase yield and reliability. iii) architectures that are fundamentally resistant to variability, including locally asynchronous designs, redundancy, and error correcting signal encodings (ECC). The literature already features works addressing the prediction of the MTTF, papers focusing on thermal management in the general purpose chip, and publications on statistical performance analysis. In my Phd research activity, I investigated the need for thermal management in future embedded low-power Network On Chip (NoC) devices.I developed a thermal analysis library, that has been integrated in a NoC cycle accurate simulator and in a FPGA based NoC simulator. The results have shown that an accurate layout distribution can avoid the onset of hot-spot in a NoC chip. Furthermore the application of thermal management can reduce temperature and number of thermal cycles, increasing the systemreliability. Therefore the thesis advocates the need to integrate a thermal analysis in the first design stages for embedded NoC design. Later on, I focused my research in the development of statistical process variation analysis tool that is able to address both random and systematic variations. The tool was used to analyze the impact of self-timed asynchronous logic stages in an embedded microprocessor. As results we confirmed the capability of self-timed logic to increase the manufacturability and reliability. Furthermore we used the tool to investigate the suitability of low-swing techniques in the NoC system communication under process variations. In this case We discovered the superior robustness to systematic process variation of low-swing links, which shows a good response to compensation technique as ASV and ABB. Hence low-swing is a good alternative to the standard CMOS communication for power, speed, reliability and manufacturability. In summary my work proves the advantage of integrating a statistical process variation analysis tool in the first stages of the design flow.

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La valutazione dell’intensità secondo una procedura formale trasparente, obiettiva e che permetta di ottenere valori numerici attraverso scelte e criteri rigorosi, rappresenta un passo ed un obiettivo per la trattazione e l’impiego delle informazioni macrosismiche. I dati macrosismici possono infatti avere importanti applicazioni per analisi sismotettoniche e per la stima della pericolosità sismica. Questa tesi ha affrontato il problema del formalismo della stima dell’intensità migliorando aspetti sia teorici che pratici attraverso tre passaggi fondamentali sviluppati in ambiente MS-Excel e Matlab: i) la raccolta e l’archiviazione del dataset macrosismico; ii), l’associazione (funzione di appartenenza o membership function) tra effetti e gradi di intensità della scala macrosismica attraverso i principi della logica dei fuzzy sets; iii) l’applicazione di algoritmi decisionali rigorosi ed obiettivi per la stima dell’intensità finale. L’intera procedura è stata applicata a sette terremoti italiani sfruttando varie possibilità, anche metodologiche, come la costruzione di funzioni di appartenenza combinando le informazioni macrosismiche di più terremoti: Monte Baldo (1876), Valle d’Illasi (1891), Marsica (1915), Santa Sofia (1918), Mugello (1919), Garfagnana (1920) e Irpinia (1930). I risultati ottenuti hanno fornito un buon accordo statistico con le intensità di un catalogo macrosismico di riferimento confermando la validità dell’intera metodologia. Le intensità ricavate sono state poi utilizzate per analisi sismotettoniche nelle aree dei terremoti studiati. I metodi di analisi statistica sui piani quotati (distribuzione geografica delle intensità assegnate) si sono rivelate in passato uno strumento potente per analisi e caratterizzazione sismotettonica, determinando i principali parametri (localizzazione epicentrale, lunghezza, larghezza, orientazione) della possibile sorgente sismogenica. Questa tesi ha implementato alcuni aspetti delle metodologie di analisi grazie a specifiche applicazioni sviluppate in Matlab che hanno permesso anche di stimare le incertezze associate ai parametri di sorgente, grazie a tecniche di ricampionamento statistico. Un’analisi sistematica per i terremoti studiati è stata portata avanti combinando i vari metodi per la stima dei parametri di sorgente con i piani quotati originali e ricalcolati attraverso le procedure decisionali fuzzy. I risultati ottenuti hanno consentito di valutare le caratteristiche delle possibili sorgenti e formulare ipotesi di natura sismotettonica che hanno avuto alcuni riscontri indiziali con dati di tipo geologico e geologico-strutturale. Alcuni eventi (1915, 1918, 1920) presentano una forte stabilità dei parametri calcolati (localizzazione epicentrale e geometria della possibile sorgente) con piccole incertezze associate. Altri eventi (1891, 1919 e 1930) hanno invece mostrato una maggiore variabilità sia nella localizzazione dell’epicentro che nella geometria delle box: per il primo evento ciò è probabilmente da mettere in relazione con la ridotta consistenza del dataset di intensità mentre per gli altri con la possibile molteplicità delle sorgenti sismogenetiche. Anche l’analisi bootstrap ha messo in evidenza, in alcuni casi, le possibili asimmetrie nelle distribuzioni di alcuni parametri (ad es. l’azimut della possibile struttura), che potrebbero suggerire meccanismi di rottura su più faglie distinte.