952 resultados para Analisi Discriminante, Teoria dei Network, Cross-Validation, Validazione.


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In questa tesi si esamineranno alcune possibili vulnerabilità dei sistemi di riconoscimento di impronte digitali e si tenterà di migliorare la loro sicurezza nei confronti di una tipologia specifica di attacco che utilizza impronte digitali "artificiali" per permettere ad un criminale di utilizzare il documento di un complice. È stata infatti recentemente dimostrata la possibilità di inserire in un documento elettronico caratteristiche biometriche che lo rendono utilizzabile da due diverse persone. Questa problematica di sicurezza è alla base dell’attacco che verrà analizzato in questa tesi e per il quale si cercheranno contromisure efficaci.

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La tesi è suddivisa in tre parti. Nella prima parte si descrive il sistema dei canali bolognesi che derivano acqua dal bacino montano del Fiume Reno e dal Torrente Savena, e il sistema di gestione e di monitoraggio utilizzato dal Consorzio dei canali di Reno e Savena. Nella seconda parte si illustra una proposta di sistema di visualizzazione dei dati idro-pluviometrici che si sta valutando, assieme al Presidente del Consorzio e ad Arpa, per il monitor che il Consorzio intende installare al fine di illustrare al pubblico il monitoraggio e l’evoluzione degli eventi di piena e di scarsità idrica/siccità. Nella terza parte, infine, si effettuano la stima e un’analisi della correlazione tra due diversi indici di siccità, meteorologica ed idrologica, per il bacino del Reno chiuso a Casalecchio. Il sistema dell’intero bacino del Reno e della rete dei canali cittadini risulta molto complesso. Vista tale complessità del sistema, si è proposto di distinguere uno scenario di piena e uno scenario di magra. Tra le diverse informazioni da visualizzare nel monitor si intendono anche visualizzare informazioni relative alla disponibilità idrica alla scala del bacino in esame. Per questo è stata svolta l’analisi sugli indici di siccità Standard Precipitation Index (SPI) e Streamflow Drought Index per il bacino del Reno chiuso a Casalecchio . Tali indici hanno portato a dei risultati consistenti con le condizioni idro-metereologiche e con le informazioni sugli impatti al suolo disponibili per alcuni degli eventi più significativi presi in esame. In base ai risultati ottenuti è possibile affermare che gli indici SPI e SDI a scala di bacino hanno una buona correlazione che permette di poter considerare anche la sola caratterizzazione pluviometrica per identificare la situazione della disponibilità idrica del fiume a monte dell’opera di presa del Canale di Reno.

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La Sentiment analysis, nata nell'ambito dell’informatica, è una delle aree di ricerca più attive nel campo dell’analisi del linguaggio naturale e si è diffusa ampiamente anche in altri rami scientifici come ad esempio le scienze sociali, l’economia e il marketing. L’enorme diffusione della sentiment analysis coincide con la crescita dei cosiddetti social media: siti di commercio e recensioni di prodotti, forum di discussione, blog, micro-blog e di vari social network. L'obiettivo del presente lavoro di tesi è stato quello di progettare un sistema di sentiment analysis in grado di rilevare e classificare le opinioni e i sentimenti espressi tramite chat dagli utenti della piattaforma di video streaming Twitch.tv. Per impostare ed organizzare il lavoro, giungendo quindi alla definizione del sistema che ci si è proposti di realizzare, sono stati utilizzati vari modelli di analisi in particolare le recurrent neural networks (RNNLM) e sistemi di word embedding (word2vec),nello specifico i Paragraph Vectors, applicandoli, dapprima, su dati etichettati in maniera automatica attraverso l'uso di emoticon e, successivamente, su dati etichettati a mano.

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The Advanced Very High Resolution Radiometer (AVHRR) carried on board the National Oceanic and Atmospheric Administration (NOAA) and the Meteorological Operational Satellite (MetOp) polar orbiting satellites is the only instrument offering more than 25 years of satellite data to analyse aerosols on a daily basis. The present study assessed a modified AVHRR aerosol optical depth τa retrieval over land for Europe. The algorithm might also be applied to other parts of the world with similar surface characteristics like Europe, only the aerosol properties would have to be adapted to a new region. The initial approach used a relationship between Sun photometer measurements from the Aerosol Robotic Network (AERONET) and the satellite data to post-process the retrieved τa. Herein a quasi-stand-alone procedure, which is more suitable for the pre-AERONET era, is presented. In addition, the estimation of surface reflectance, the aerosol model, and other processing steps have been adapted. The method's cross-platform applicability was tested by validating τa from NOAA-17 and NOAA-18 AVHRR at 15 AERONET sites in Central Europe (40.5° N–50° N, 0° E–17° E) from August 2005 to December 2007. Furthermore, the accuracy of the AVHRR retrieval was related to products from two newer instruments, the Medium Resolution Imaging Spectrometer (MERIS) on board the Environmental Satellite (ENVISAT) and the Moderate Resolution Imaging Spectroradiometer (MODIS) on board Aqua/Terra. Considering the linear correlation coefficient R, the AVHRR results were similar to those of MERIS with even lower root mean square error RMSE. Not surprisingly, MODIS, with its high spectral coverage, gave the highest R and lowest RMSE. Regarding monthly averaged τa, the results were ambiguous. Focusing on small-scale structures, R was reduced for all sensors, whereas the RMSE solely for MERIS substantially increased. Regarding larger areas like Central Europe, the error statistics were similar to the individual match-ups. This was mainly explained with sampling issues. With the successful validation of AVHRR we are now able to concentrate on our large data archive dating back to 1985. This is a unique opportunity for both climate and air pollution studies over land surfaces.

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This paper studies the energy-efficiency and service characteristics of a recently developed energy-efficient MAC protocol for wireless sensor networks in simulation and on a real sensor hardware testbed. This opportunity is seized to illustrate how simulation models can be verified by cross-comparing simulation results with real-world experiment results. The paper demonstrates that by careful calibration of simulation model parameters, the inevitable gap between simulation models and real-world conditions can be reduced. It concludes with guidelines for a methodology for model calibration and validation of sensor network simulation models.

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Computational network analysis provides new methods to analyze the brain's structural organization based on diffusion imaging tractography data. Networks are characterized by global and local metrics that have recently given promising insights into diagnosis and the further understanding of psychiatric and neurologic disorders. Most of these metrics are based on the idea that information in a network flows along the shortest paths. In contrast to this notion, communicability is a broader measure of connectivity which assumes that information could flow along all possible paths between two nodes. In our work, the features of network metrics related to communicability were explored for the first time in the healthy structural brain network. In addition, the sensitivity of such metrics was analysed using simulated lesions to specific nodes and network connections. Results showed advantages of communicability over conventional metrics in detecting densely connected nodes as well as subsets of nodes vulnerable to lesions. In addition, communicability centrality was shown to be widely affected by the lesions and the changes were negatively correlated with the distance from lesion site. In summary, our analysis suggests that communicability metrics that may provide an insight into the integrative properties of the structural brain network and that these metrics may be useful for the analysis of brain networks in the presence of lesions. Nevertheless, the interpretation of communicability is not straightforward; hence these metrics should be used as a supplement to the more standard connectivity network metrics.

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BACKGROUND Recently, two simple clinical scores were published to predict survival in trauma patients. Both scores may successfully guide major trauma triage, but neither has been independently validated in a hospital setting. METHODS This is a cohort study with 30-day mortality as the primary outcome to validate two new trauma scores-Mechanism, Glasgow Coma Scale (GCS), Age, and Pressure (MGAP) score and GCS, Age and Pressure (GAP) score-using data from the UK Trauma Audit and Research Network. First, an assessment of discrimination, using the area under the receiver operating characteristic (ROC) curve, and calibration, comparing mortality rates with those originally published, were performed. Second, we calculated sensitivity, specificity, predictive values, and likelihood ratios for prognostic score performance. Third, we propose new cutoffs for the risk categories. RESULTS A total of 79,807 adult (≥16 years) major trauma patients (2000-2010) were included; 5,474 (6.9%) died. Mean (SD) age was 51.5 (22.4) years, median GCS score was 15 (interquartile range, 15-15), and median Injury Severity Score (ISS) was 9 (interquartile range, 9-16). More than 50% of the patients had a low-risk GAP or MGAP score (1% mortality). With regard to discrimination, areas under the ROC curve were 87.2% for GAP score (95% confidence interval, 86.7-87.7) and 86.8% for MGAP score (95% confidence interval, 86.2-87.3). With regard to calibration, 2,390 (3.3%), 1,900 (28.5%), and 1,184 (72.2%) patients died in the low, medium, and high GAP risk categories, respectively. In the low- and medium-risk groups, these were almost double the previously published rates. For MGAP, 1,861 (2.8%), 1,455 (15.2%), and 2,158 (58.6%) patients died in the low-, medium-, and high-risk categories, consonant with results originally published. Reclassifying score point cutoffs improved likelihood ratios, sensitivity and specificity, as well as areas under the ROC curve. CONCLUSION We found both scores to be valid triage tools to stratify emergency department patients, according to their risk of death. MGAP calibrated better, but GAP slightly improved discrimination. The newly proposed cutoffs better differentiate risk classification and may therefore facilitate hospital resource allocation. LEVEL OF EVIDENCE Prognostic study, level II.

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Esta tesis está incluida dentro del campo del campo de Multiband Orthogonal Frequency Division Multiplexing Ultra Wideband (MB-OFDM UWB), el cual ha adquirido una gran importancia en las comunicaciones inalámbricas de alta tasa de datos en la última década. UWB surgió con el objetivo de satisfacer la creciente demanda de conexiones inalámbricas en interiores y de uso doméstico, con bajo coste y alta velocidad. La disponibilidad de un ancho de banda grande, el potencial para alta velocidad de transmisión, baja complejidad y bajo consumo de energía, unido al bajo coste de implementación, representa una oportunidad única para que UWB se convierta en una solución ampliamente utilizada en aplicaciones de Wireless Personal Area Network (WPAN). UWB está definido como cualquier transmisión que ocupa un ancho de banda de más de 20% de su frecuencia central, o más de 500 MHz. En 2002, la Comisión Federal de Comunicaciones (FCC) definió que el rango de frecuencias de transmisión de UWB legal es de 3.1 a 10.6 GHz, con una energía de transmisión de -41.3 dBm/Hz. Bajo las directrices de FCC, el uso de la tecnología UWB puede aportar una enorme capacidad en las comunicaciones de corto alcance. Considerando las ecuaciones de capacidad de Shannon, incrementar la capacidad del canal requiere un incremento lineal en el ancho de banda, mientras que un aumento similar de la capacidad de canal requiere un aumento exponencial en la energía de transmisión. En los últimos años, s diferentes desarrollos del UWB han sido extensamente estudiados en diferentes áreas, entre los cuales, el protocolo de comunicaciones inalámbricas MB-OFDM UWB está considerado como la mejor elección y ha sido adoptado como estándar ISO/IEC para los WPANs. Combinando la modulación OFDM y la transmisión de datos utilizando las técnicas de salto de frecuencia, el sistema MB-OFDM UWB es capaz de soportar tasas de datos con que pueden variar de los 55 a los 480 Mbps, alcanzando una distancia máxima de hasta 10 metros. Se esperara que la tecnología MB-OFDM tenga un consumo energético muy bajo copando un are muy reducida en silicio, proporcionando soluciones de bajo coste que satisfagan las demandas del mercado. Para cumplir con todas estas expectativas, el desarrollo y la investigación del MBOFDM UWB deben enfrentarse a varios retos, como son la sincronización de alta sensibilidad, las restricciones de baja complejidad, las estrictas limitaciones energéticas, la escalabilidad y la flexibilidad. Tales retos requieren un procesamiento digital de la señal de última generación, capaz de desarrollar sistemas que puedan aprovechar por completo las ventajas del espectro UWB y proporcionar futuras aplicaciones inalámbricas en interiores. Esta tesis se centra en la completa optimización de un sistema de transceptor de banda base MB-OFDM UWB digital, cuyo objetivo es investigar y diseñar un subsistema de comunicación inalámbrica para la aplicación de las Redes de Sensores Inalámbricas Visuales. La complejidad inherente de los procesadores FFT/IFFT y el sistema de sincronización así como la alta frecuencia de operación para todos los elementos de procesamiento, se convierten en el cuello de la botella para el diseño y la implementación del sistema de UWB digital en base de banda basado en MB-OFDM de baja energía. El objetivo del transceptor propuesto es conseguir baja energía y baja complejidad bajo la premisa de un alto rendimiento. Las optimizaciones están realizadas tanto a nivel algorítmico como a nivel arquitectural para todos los elementos del sistema. Una arquitectura hardware eficiente en consumo se propone en primer lugar para aquellos módulos correspondientes a núcleos de computación. Para el procesado de la Transformada Rápida de Fourier (FFT/IFFT), se propone un algoritmo mixed-radix, basado en una arquitectura con pipeline y se ha desarrollado un módulo de Decodificador de Viterbi (VD) equilibrado en coste-velocidad con el objetivo de reducir el consumo energético e incrementar la velocidad de procesamiento. También se ha implementado un correlador signo-bit simple basado en la sincronización del tiempo de símbolo es presentado. Este correlador es usado para detectar y sincronizar los paquetes de OFDM de forma robusta y precisa. Para el desarrollo de los subsitemas de procesamiento y realizar la integración del sistema completo se han empleado tecnologías de última generación. El dispositivo utilizado para el sistema propuesto es una FPGA Virtex 5 XC5VLX110T del fabricante Xilinx. La validación el propuesta para el sistema transceptor se ha implementado en dicha placa de FPGA. En este trabajo se presenta un algoritmo, y una arquitectura, diseñado con filosofía de co-diseño hardware/software para el desarrollo de sistemas de FPGA complejos. El objetivo principal de la estrategia propuesta es de encontrar una metodología eficiente para el diseño de un sistema de FPGA configurable optimizado con el empleo del mínimo esfuerzo posible en el sistema de procedimiento de verificación, por tanto acelerar el periodo de desarrollo del sistema. La metodología de co-diseño presentada tiene la ventaja de ser fácil de usar, contiene todos los pasos desde la propuesta del algoritmo hasta la verificación del hardware, y puede ser ampliamente extendida para casi todos los tipos de desarrollos de FPGAs. En este trabajo se ha desarrollado sólo el sistema de transceptor digital de banda base por lo que la comprobación de señales transmitidas a través del canal inalámbrico en los entornos reales de comunicación sigue requiriendo componentes RF y un front-end analógico. No obstante, utilizando la metodología de co-simulación hardware/software citada anteriormente, es posible comunicar el sistema de transmisor y el receptor digital utilizando los modelos de canales propuestos por IEEE 802.15.3a, implementados en MATLAB. Por tanto, simplemente ajustando las características de cada modelo de canal, por ejemplo, un incremento del retraso y de la frecuencia central, podemos estimar el comportamiento del sistema propuesto en diferentes escenarios y entornos. Las mayores contribuciones de esta tesis son: • Se ha propuesto un nuevo algoritmo 128-puntos base mixto FFT usando la arquitectura pipeline multi-ruta. Los complejos multiplicadores para cada etapa de procesamiento son diseñados usando la arquitectura modificada shiftadd. Los sistemas word length y twiddle word length son comparados y seleccionados basándose en la señal para cuantización del SQNR y el análisis de energías. • El desempeño del procesador IFFT es analizado bajo diferentes situaciones aritméticas de bloques de punto flotante (BFP) para el control de desbordamiento, por tanto, para encontrar la arquitectura perfecta del algoritmo IFFT basado en el procesador FFT propuesto. • Para el sistema de receptor MB-OFDM UWB se ha empleado una sincronización del tiempo innovadora, de baja complejidad y esquema de compensación, que consiste en funciones de Detector de Paquetes (PD) y Estimación del Offset del tiempo. Simplificando el cross-correlation y maximizar las funciones probables solo a sign-bit, la complejidad computacional se ve reducida significativamente. • Se ha propuesto un sistema de decodificadores Viterbi de 64 estados de decisión-débil usando velocidad base-4 de arquitectura suma-comparaselecciona. El algoritmo Two-pointer Even también es introducido en la unidad de rastreador de origen con el objetivo de conseguir la eficiencia en el hardware. • Se han integrado varias tecnologías de última generación en el completo sistema transceptor basebanda , con el objetivo de implementar un sistema de comunicación UWB altamente optimizado. • Un diseño de flujo mejorado es propuesto para el complejo sistema de implementación, el cual puede ser usado para diseños de Cadena de puertas de campo programable general (FPGA). El diseño mencionado no sólo reduce dramáticamente el tiempo para la verificación funcional, sino también provee un análisis automático como los errores del retraso del output para el sistema de hardware implementado. • Un ambiente de comunicación virtual es establecido para la validación del propuesto sistema de transceptores MB-OFDM. Este método es provisto para facilitar el uso y la conveniencia de analizar el sistema digital de basebanda sin parte frontera analógica bajo diferentes ambientes de comunicación. Esta tesis doctoral está organizada en seis capítulos. En el primer capítulo se encuentra una breve introducción al campo del UWB, tanto relacionado con el proyecto como la motivación del desarrollo del sistema de MB-OFDM. En el capítulo 2, se presenta la información general y los requisitos del protocolo de comunicación inalámbrica MBOFDM UWB. En el capítulo 3 se habla de la arquitectura del sistema de transceptor digital MB-OFDM de banda base . El diseño del algoritmo propuesto y la arquitectura para cada elemento del procesamiento está detallado en este capítulo. Los retos de diseño del sistema que involucra un compromiso de discusión entre la complejidad de diseño, el consumo de energía, el coste de hardware, el desempeño del sistema, y otros aspectos. En el capítulo 4, se ha descrito la co-diseñada metodología de hardware/software. Cada parte del flujo del diseño será detallado con algunos ejemplos que se ha hecho durante el desarrollo del sistema. Aprovechando esta estrategia de diseño, el procedimiento de comunicación virtual es llevado a cabo para probar y analizar la arquitectura del transceptor propuesto. Los resultados experimentales de la co-simulación y el informe sintético de la implementación del sistema FPGA son reflejados en el capítulo 5. Finalmente, en el capítulo 6 se incluye las conclusiones y los futuros proyectos, y también los resultados derivados de este proyecto de doctorado. ABSTRACT In recent years, the Wireless Visual Sensor Network (WVSN) has drawn great interest in wireless communication research area. They enable a wealth of new applications such as building security control, image sensing, and target localization. However, nowadays wireless communication protocols (ZigBee, Wi-Fi, and Bluetooth for example) cannot fully satisfy the demands of high data rate, low power consumption, short range, and high robustness requirements. New communication protocol is highly desired for such kind of applications. The Ultra Wideband (UWB) wireless communication protocol, which has increased in importance for high data rate wireless communication field, are emerging as an important topic for WVSN research. UWB has emerged as a technology that offers great promise to satisfy the growing demand for low-cost, high-speed digital wireless indoor and home networks. The large bandwidth available, the potential for high data rate transmission, and the potential for low complexity and low power consumption, along with low implementation cost, all present a unique opportunity for UWB to become a widely adopted radio solution for future Wireless Personal Area Network (WPAN) applications. UWB is defined as any transmission that occupies a bandwidth of more than 20% of its center frequency, or more than 500 MHz. In 2002, the Federal Communications Commission (FCC) has mandated that UWB radio transmission can legally operate in the range from 3.1 to 10.6 GHz at a transmitter power of -41.3 dBm/Hz. Under the FCC guidelines, the use of UWB technology can provide enormous capacity over short communication ranges. Considering Shannon’s capacity equations, increasing the channel capacity requires linear increasing in bandwidth, whereas similar channel capacity increases would require exponential increases in transmission power. In recent years, several different UWB developments has been widely studied in different area, among which, the MB-OFDM UWB wireless communication protocol is considered to be the leading choice and has recently been adopted in the ISO/IEC standard for WPANs. By combing the OFDM modulation and data transmission using frequency hopping techniques, the MB-OFDM UWB system is able to support various data rates, ranging from 55 to 480 Mbps, over distances up to 10 meters. The MB-OFDM technology is expected to consume very little power and silicon area, as well as provide low-cost solutions that can satisfy consumer market demands. To fulfill these expectations, MB-OFDM UWB research and development have to cope with several challenges, which consist of high-sensitivity synchronization, low- complexity constraints, strict power limitations, scalability, and flexibility. Such challenges require state-of-the-art digital signal processing expertise to develop systems that could fully take advantages of the UWB spectrum and support future indoor wireless applications. This thesis focuses on fully optimization for the MB-OFDM UWB digital baseband transceiver system, aiming at researching and designing a wireless communication subsystem for the Wireless Visual Sensor Networks (WVSNs) application. The inherent high complexity of the FFT/IFFT processor and synchronization system, and high operation frequency for all processing elements, becomes the bottleneck for low power MB-OFDM based UWB digital baseband system hardware design and implementation. The proposed transceiver system targets low power and low complexity under the premise of high performance. Optimizations are made at both algorithm and architecture level for each element of the transceiver system. The low-power hardwareefficient structures are firstly proposed for those core computation modules, i.e., the mixed-radix algorithm based pipelined architecture is proposed for the Fast Fourier Transform (FFT/IFFT) processor, and the cost-speed balanced Viterbi Decoder (VD) module is developed, in the aim of lowering the power consumption and increasing the processing speed. In addition, a low complexity sign-bit correlation based symbol timing synchronization scheme is presented so as to detect and synchronize the OFDM packets robustly and accurately. Moreover, several state-of-the-art technologies are used for developing other processing subsystems and an entire MB-OFDM digital baseband transceiver system is integrated. The target device for the proposed transceiver system is Xilinx Virtex 5 XC5VLX110T FPGA board. In order to validate the proposed transceiver system in the FPGA board, a unified algorithm-architecture-circuit hardware/software co-design environment for complex FPGA system development is presented in this work. The main objective of the proposed strategy is to find an efficient methodology for designing a configurable optimized FPGA system by using as few efforts as possible in system verification procedure, so as to speed up the system development period. The presented co-design methodology has the advantages of easy to use, covering all steps from algorithm proposal to hardware verification, and widely spread for almost all kinds of FPGA developments. Because only the digital baseband transceiver system is developed in this thesis, the validation of transmitting signals through wireless channel in real communication environments still requires the analog front-end and RF components. However, by using the aforementioned hardware/software co-simulation methodology, the transmitter and receiver digital baseband systems get the opportunity to communicate with each other through the channel models, which are proposed from the IEEE 802.15.3a research group, established in MATLAB. Thus, by simply adjust the characteristics of each channel model, e.g. mean excess delay and center frequency, we can estimate the transmission performance of the proposed transceiver system through different communication situations. The main contributions of this thesis are: • A novel mixed radix 128-point FFT algorithm by using multipath pipelined architecture is proposed. The complex multipliers for each processing stage are designed by using modified shift-add architectures. The system wordlength and twiddle word-length are compared and selected based on Signal to Quantization Noise Ratio (SQNR) and power analysis. • IFFT processor performance is analyzed under different Block Floating Point (BFP) arithmetic situations for overflow control, so as to find out the perfect architecture of IFFT algorithm based on the proposed FFT processor. • An innovative low complex timing synchronization and compensation scheme, which consists of Packet Detector (PD) and Timing Offset Estimation (TOE) functions, for MB-OFDM UWB receiver system is employed. By simplifying the cross-correlation and maximum likelihood functions to signbit only, the computational complexity is significantly reduced. • A 64 state soft-decision Viterbi Decoder system by using high speed radix-4 Add-Compare-Select architecture is proposed. Two-pointer Even algorithm is also introduced into the Trace Back unit in the aim of hardware-efficiency. • Several state-of-the-art technologies are integrated into the complete baseband transceiver system, in the aim of implementing a highly-optimized UWB communication system. • An improved design flow is proposed for complex system implementation which can be used for general Field-Programmable Gate Array (FPGA) designs. The design method not only dramatically reduces the time for functional verification, but also provides automatic analysis such as errors and output delays for the implemented hardware systems. • A virtual communication environment is established for validating the proposed MB-OFDM transceiver system. This methodology is proved to be easy for usage and convenient for analyzing the digital baseband system without analog frontend under different communication environments. This PhD thesis is organized in six chapters. In the chapter 1 a brief introduction to the UWB field, as well as the related work, is done, along with the motivation of MBOFDM system development. In the chapter 2, the general information and requirement of MB-OFDM UWB wireless communication protocol is presented. In the chapter 3, the architecture of the MB-OFDM digital baseband transceiver system is presented. The design of the proposed algorithm and architecture for each processing element is detailed in this chapter. Design challenges of such system involve trade-off discussions among design complexity, power consumption, hardware cost, system performance, and some other aspects. All these factors are analyzed and discussed. In the chapter 4, the hardware/software co-design methodology is proposed. Each step of this design flow will be detailed by taking some examples that we met during system development. Then, taking advantages of this design strategy, the Virtual Communication procedure is carried out so as to test and analyze the proposed transceiver architecture. Experimental results from the co-simulation and synthesis report of the implemented FPGA system are given in the chapter 5. The chapter 6 includes conclusions and future work, as well as the results derived from this PhD work.

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Following the processing and validation of JEFF-3.1 performed in 2006 and presented in ND2007, and as a consequence of the latest updated of this library (JEFF-3.1.2) in February 2012, a new processing and validation of JEFF-3.1.2 cross section library is presented in this paper. The processed library in ACE format at ten different temperatures was generated with NJOY-99.364 nuclear data processing system. In addition, NJOY-99 inputs are provided to generate PENDF, GENDF, MATXSR and BOXER formats. The library has undergone strict QA procedures, being compared with other available libraries (e.g. ENDF/B-VII.1) and processing codes as PREPRO-2000 codes. A set of 119 criticality benchmark experiments taken from ICSBEP-2010 has been used for validation purposes.

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La presente tesi si occupa di identificare la metodologia utilizzata per la definizione di percorsi Real Driving Emissions. Nel particolare sono stati individuati due percorsi, uno in piano, definite RDE Moderate Track ed uno in quota, definito RDE Extended Track. Si è anche eseguita una analisi dei cicli su banco a rulli NEDC e WLTC in ottica Real Driving Emissions.

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Nel presente elaborato mi propongo di sviluppare un’analisi sulla letteratura postcoloniale, concentrandomi su un ramo specifico di quest’ultima, la black British literature, con annessa proposta di traduzione di alcuni capitoli del romanzo “Never far from nowhere”, pubblicato nel 1996 da una delle maggiori esponenti della narrativa black British, la scrittrice inglese di origini giamaicane Andrea Levy.  Nel primo capitolo, l’intento principale è quello di far luce sulle analogie esistenti fra traduzione letteraria e letteratura postcoloniale.  Nel secondo capitolo, mi concentrerò in particolare sulla black British literature: la narrativa inglese prodotta dagli immigrati provenienti dai Paesi del Commonwealth, sviluppatasi in Gran Bretagna in seguito al flusso migratorio degli anni Cinquanta.  Il terzo capitolo sarà dedicato alla biografia e alle opere di Andrea Levy, agli episodi che hanno in qualche modo segnato la sua vita e determinato la sua scelta di diventare scrittrice.  Nel quarto capitolo, infine, presenterò il romanzo che ho scelto di tradurre, Never far from nowhere. Seguirà un commento alla traduzione in cui ripercorro tutti i passaggi che mi sono parsi più problematici da tradurre.  L’obiettivo di questo elaborato è di valorizzare un genere letterario che è stato a lungo sottovalutato, nonostante la sua enorme portata storica e ideologica, il suo carattere di testimonianza e la valenza che ha assunto non solo per l’identità black British, ma per l’identità britannica a tutto tondo.

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L'elaborato è focalizzato sul dimensionamento di un sistema solare termico da integrare ad una caldaia a metano in una palestra di riferimento. Sono state condotte simulazioni dinamiche in ambiente Trnsys per analizzare il consumo energetico dell'utenza termica, eseguite anche al variare dei valori di differenti variabili. Infine sono state condotte valutazioni economiche, tramite parametri finanziari, per decretare la fattibilità e la convenienza dell'investimento.

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Questo elaborato nasce con l’obiettivo di trovare quali indicatori sono maggiormente indicativi delle reali performance ambientali ed economiche nella gestione dei rifiuti urbani al fine di studiare la situazione attuale e le cause che maggiormente influenzano la qualità della gestione del servizio. Il lavoro di analisi dei dati è stato diviso in quattro fasi principali. Inizialmente sono stati raccolti dati pubblici relativi ai vari Comuni della Provincia di Bologna per la successiva creazione di indicatori complessi, indispensabili sia per il confronto dei dati stessi, che delle varie categorie e delle classi create in seguito. Infine lo sviluppo dei grafici ha permesso di mettere in relazione i vari elementi in modo da fornire una chiara rappresentazione di come questi possano influire sui costi e sulle tematiche ambientali.