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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
141

O tempo em cena: experimentação dramatúrgica em Mão na Luva, de Oduvaldo Vianna Filho / Time on stage: dramaturgic experience in Mão na Luva, from Oduvaldo Vianna Filho.

Zaidan, Simone Mello 28 March 2011 (has links)
Análise interpretativa do texto dramatúrgico Mão na Luva (ou Corpo a Corpo - 1966), de Oduvaldo Vianna Filho (1936-1974). São analisados, entre outros aspectos, as rubricas que dizem respeito à estrutura temporal e ao recurso do play-back como índices da presença dos gêneros épico e lírico junto ao dramático; assim como buscamos identificar relações estéticas deste texto com peças de outros autores. / This work has, as its main goal, the interpretative analysis of the play Mão na Luva (or Corpo a Corpo - 1966), from Oduvaldo Vianna Filho (1936-1974). Among other aspects, we will analyze the rubricas about time structure and play-back as signals of epic and lyric genres presence, joined to the dramatic; as well as we will search for the esthetic relation between this play and other authors\' works.
142

Valorisation énergétique des sous-produits agricoles en zone sub-saharienne : pré-conditionnement de la biomasse par pyrolyse flash / Energetic valorisation of agricultural by-products in the sub-Saharan zone : biomass preconditioning via flash pyrolysis

Melzer, Michael 20 September 2013 (has links)
L’Afrique de l'Ouest manque de ressources naturelles pour la production d'énergie. Les sous-produits agro-industriels comme les coques d’anacarde (CNS), les tourteaux de jatropha et de karité ont été identifiés comme des ressources disponibles et facilement mobilisables à des fins énergétiques. Ces biomasses se caractérisent par de fortes teneurs en extractibles (baume de cajou=CNSL ou triglycérides), sources de fumées toxiques en combustion. La thèse visait à évaluer la pertinence de la pyrolyse rapide comme procédé alternatif pour ces ressources, etplus particulièrement à établir l'impact des extractibles sur les rendements, la composition et la stabilité des bio-huiles. Les biomasses ont été dérivées en échantillons couvrant la gamme entière des teneurs en extractibles (tourteau déshuilé ~0% ; extractible purs 100%), lesquels ont été caractérisés et pyrolysés dans 2 dispositifs laboratoires (ATG et four tubulaire), puis en conditions réelles sur un pilote de pyrolyse rapide à lit fluidisé. On ne constate pas d'interaction significative entre la matrice solide et les extractibles lors de leur décomposition, mais des produits différents ont été identifiés. Le CNSL se volatilise entre 250 et 320°C ; plusieurs composés phénoliques ou typiques du CNSL brut se retrouvent dans l'huile de pyrolyse. En revanche, les triglycérides se décomposent entièrement entre 380 et 420°C en chaînes d’hydrocarbures linéaires. Quelques produits d'interaction avec les triglycérides et les protéines ont été identifiés. Par ailleurs, les essais sur pilote ont mis en évidence des difficultés opérationnelles dans le lit fluidisé liées aux spécificités des tourteaux, suggérant une optimisation des conditions opératoires. Pour pallier la séparation de phases constatée sur les bio-huiles, des formulations avec d'autres biocarburants ont été testées. Les émulsions obtenues sont plus homogènes, mais leur stabilité physique est encore insuffisante malgré l'ajout / Sub-Saharan West Africa lacks of natural resources, especially for energy production. By-products of agro-industry as cashew nut shells (CNS), jatropha (Jc) and shea (Sc) press cakes were identified as available resources for energetic valorisation. These biomasses are characterized by high extractive contents (cashew nut shell liquid/CNSL or triglycerides) which are the reason for toxic fumes during combustion. The thesis investigated the feasibility of flash pyrolysis as alternative process for these resources, more specifically the impact of the extractives on yields, the composition and the stability of flash pyrolysis oils. The feedstock were derived into samples covering the whole range of extractive contents (from de-oiled press cakes, ~0 wt%; to pure extractives, 100 wt%) which were characterized and pyrolysed in two laboratory devices (TGA and tubular furnace), then by applying flash pyrolysis conditions in a fluidized bed reactor. No significant interaction in-between the solid matrix and the extractives during pyrolysis were observed but different products were identified. CNSL volatises between 250 and 320°C, several phenolic compounds and typical compounds of crude CNSL were found to be present in the pyrolysis oil. In contrast, triglycerides are entirely decomposed at 380 to 420°C to give linear hydro-carbon chains. Some interaction products of the triglycerides with proteins were identified. Additionally, the experiments with the pilot plant have shown operational difficulties in the fluidized bed, which are linked to specific properties of the press cakes. Thus, further optimisations of process conditions are suggested. To overcome the observed phase separation of the pyrolysis oils mixtures with other biofuels were studied. The obtained emulsions are more homogeneous but the physical stability is still insufficient despite the addition of surfactants.
143

Observation depuis le sol et analyse des émissions associées aux chutes des météorites sur la lune / Observation from the ground and analysis of emissions associated with meteoroides falling on the moon

Ait Moulay Larbi, El mamoun 30 September 2016 (has links)
Les météoroïdes, issus de petits corps du système solaire produisent des phénomènes lumineux (flashs d'impact) lorsqu'ils percutent le sol de la Lune. Ces événements lumineux transitoires sont observables depuis le sol en utilisant des télescopes de taille moyenne (typiquement > 200 mm de diamètre) à l'aide des caméras CCD rapides de haute sensibilité. Dans cette thèse, nous décrivons la configuration instrumentale, la procédure d'observation et d'analyse qui a été implémentée à l'Observatoire Universitaire de l'Oukaimden pour l'observation régulière des flashs lunaires. Les premiers impacts lunaires observés et confirmés depuis un observatoire situé en Afrique et dans le monde arabe sont analysés dans ce manuscrit. Nous discutons les caractéristiques de cinq flashs et les paramètres physiques attribués aux impacteurs associés. Nous présentons une première estimation du flux d'impact à l'issue de cette phase de surveillance des impacts lunaires depuis nos observatoires. Nous présentons également le développement et le test d'une stratégie pour déterminer avec précision les coordonnées des impacts observés depuis la Terre. Cette précision de séléno-localisation pourra être utilisée au profit de futures missions sismologiques qui utiliseront les impacts météoritiques pour explorer l'intérieur lunaire. / Meteoroids, coming from small bodies of the solar system, produce luminous phenomena (impact flashes) when they strike the lunar surface. These transient light events are observable from the ground using medium-sized telescopes (typically> 200 mm in diameter) by using high-speed CCD cameras. In this thesis, we describe the instrumental configuration, observation and analysis procedure that was implemented at the Oukaimden Observatory for regular observation of lunar flashes. The first lunar impacts observed and confirmed from an observatory located in Africa and the Arab world are analyzed in this manuscript. We discuss the characteristics of five flashes and the physical parameters attributed to the associated impactors. We present an initial estimate of the impact flux from this first phase of monitoring lunar impacts from our observatories. We also present the development and testing of a strategy to accurately determine the coordinates of impacts observed from Earth. This precision of seleno-localization can be used for future seismological missions that will use meteoroid impacts to explore the lunar interior.
144

PREDICTIVE MODELING OF DC ARC FLASH IN 125 VOLT SYSTEM

Gaunce, Austin Cody 01 January 2019 (has links)
Arc flash is one of the two primary hazards encountered by workers near electrical equipment. Most applications where arc flash may be encountered are alternating current (AC) electrical systems. However, direct current (DC) electrical systems are becoming increasingly prevalent with industries implementing more renewable energy sources and energy storage devices. Little research has been performed with respect to arc flash hazards posed by DC electrical systems, particularly energy storage devices. Furthermore, current standards for performing arc flash calculations do not provide sufficient guidance when working in DC applications. IEEE 1584-2002 does not provide recommendations for DC electrical systems. NFPA 70E provides recommendations based on conservative theoretical models, which may result in excessive personal protective equipment (PPE). Arc flash calculations seek to quantify incident energy, which quantifies the amount of thermal energy that a worker may be exposed to at some working distance. This thesis assesses arc flash hazards within a substation backup battery system. In addition, empirical data collected via a series of tests utilizing retired station batteries is presented. Lastly, a predictive model for determining incident energy is proposed, based on collected data.
145

1 GS/s, Low Power Flash, Analog to Digital Converter in 90nm CMOS Technology

Hassan Raza Naqvi, Syed January 2007 (has links)
<p>The analog to digital converters is the key components in modern electronic systems. As the digital signal processing industry grows the ADC design becomes more and more challenging for researchers. In these days an ADC becomes a part of the system on chip instead of standalone circuit for data converters. This increases the requirements on ADC design concerning for example speed, power, area, resolution, noise etc. New techniques and methods are going to develop day by day to achieve high performance ADCs.</p><p>Of all types of ADCs the flash ADC is not only famous for its data conversion rate but also it becomes the part of other types of ADC for example pipeline and multi bit Sigma Delta ADCs. The main problem with a flash ADC is its power consumption, which increases in number of bits. This thesis presents the comparison of power consumption of different blocks in 1Gbps flash ADCs for 2, 4 and 6 bits in a 90nm CMOS technology. We also investigate the impact on power consumption by changing the design of decoder block.</p>
146

1 GS/s, Low Power Flash, Analog to Digital Converter in 90nm CMOS Technology

Hassan Raza Naqvi, Syed January 2007 (has links)
The analog to digital converters is the key components in modern electronic systems. As the digital signal processing industry grows the ADC design becomes more and more challenging for researchers. In these days an ADC becomes a part of the system on chip instead of standalone circuit for data converters. This increases the requirements on ADC design concerning for example speed, power, area, resolution, noise etc. New techniques and methods are going to develop day by day to achieve high performance ADCs. Of all types of ADCs the flash ADC is not only famous for its data conversion rate but also it becomes the part of other types of ADC for example pipeline and multi bit Sigma Delta ADCs. The main problem with a flash ADC is its power consumption, which increases in number of bits. This thesis presents the comparison of power consumption of different blocks in 1Gbps flash ADCs for 2, 4 and 6 bits in a 90nm CMOS technology. We also investigate the impact on power consumption by changing the design of decoder block.
147

Design And Simulation Of A Flash Translation Layer Algorithm

Ayar, Yusuf Yavuz 01 June 2010 (has links) (PDF)
Flash Memories have been widely used as a storage media in electronic devices such as USB flash drives, mobile phones and cameras. Flash Memory offers a portable and non-volatile de- sign, which can be carried to everywhere without data loss. It is durable against temperature and humidity. With all these advantages, Flash Memory gets popular day by day. However, Flash Memory has also some disadvantages, such as erase-before restriction and erase limi- tation of each individual block. Erase-before restriction pushes every single writable unit to be erased before an update operation. Another limitation is that every block can be erased up to a fixed number. Flash Translation Layer - FTL is the solution for these disadvantages. Flash Translation Layer is a software module inside the Flash Memory working between the operating system and the memory. FTL tries to reduce these disadvantages of Flash Memory via implementing garbage collector, address mapping scheme, error correcting and many oth- ers. There are various Flash Translation Layer software. Some of them have been reviewed in terms of their advantages and disadvantages. The study aims at designing, implementing and simulating a NAND type FTL algorithm.
148

Interaktivt Säljstöd-Flash presentation av Stöt Puls Metoden / Interactive Sale Support-Flash presentation of the Shock Pulse Method

Ekman, Linda January 2002 (has links)
<p>Denna rapport är en beskrivning av ett examensarbete utfört vid SPM Instrument AB i Strängnäs. SPM Instrument utvecklar och tillverkar produkter för konditionsmätning av maskiner. </p><p>Målet var att skapa en cd-presentation i redigeringsprogrammet Macromedia Flash 5.0, som på ett enkelt sätt med rörliga bilder förklarar en konditionsmätningsmetod som kallas för Stöt Puls Metoden.</p><p>Uppgiften löstes genom att först inhämta information om Stöt Puls Metoden, sedan utformades Flash-filmen och slutligen testades och utvecklades filmen tills dess att jag och SPM Instrument var nöjda. </p> / <p>This report describes a final-year project performed at SPM Instrument AB in Strängnäs. The company develop and manufacture products for condition monitoring of machinery equipment. </p><p>The goal was to create a cd-presentation in the computer software Macromedia Flash 5.0, with moving pictures which explains a condition monitoring method that is called the Shoke Pulse Method. </p><p>The task was solved by first finding out information about the Shoke Pulse Method, then the Flash-movie was created and finally the movie was tested and developed until both I and SPM Instrument was satisfied.</p>
149

Κωδικοποίηση και διόρθωση λαθών σε μνήμες NAND πολλαπλών επιπέδων

Ευταξιάδης, Ευστράτιος, Μπίκας, Γεώργιος 09 October 2014 (has links)
Οι MLC NAND Flash μνήμες παίζουν πρωταγωνιστικό ρόλο για την αποθήκευση δε- δομένων, καθώς έχουν μεγάλη αποθηκευτική ικανότητα λόγω της μεγάλης πυκνότητάς τους, χαμηλό κόστος και χαμηλή απαίτηση σε ισχύ. Για τους λόγους αυτούς, έγινε εφικτό από τους σκληρούς δίσκους οδήγησης (HDDs) πλέον έχουμε περάσει στην εποχή των Solid State Drives (SSDs) που αποτελούν ένα μεγάλο βήμα για την αποθήκευση δεδομένων αποδοτικά και αξιόπιστα. Βέβαια η παρουσία λαθών στις MLC NAND Flash μνήμες, λόγω φαινομένων όπως η γήρανση του υλικού καθιστά απαραίτητη την εφαρμογή κωδίκων διόρθωσης λαθών (ECC) ώστε να διατηρηθεί η αξιοπιστία σε επιθυμητά επίπεδα. Σκοπός λοιπόν αυτής της διπλωματικής είναι αρχικά η ανάπτυξη ενός παραμετροποιήσιμου μοντέλου MLC NAND Flash μνήμης για την εξομοίωση εμφάνισης λαθών. Στη συνέχεια η χρησιμοποίηση soft-decision Low Density Parity Check (LDPC) κωδίκων για τη διόρθωση λαθών με τέτοι οτρόπο ώστε να παρατείνουμε το χρόνο ζωής της μνήμης και τελικά να υπολογίσουμε το Life Time Capacity που αποτελεί το συνολικό μέγεθος της πληροφορίας που μπορεί να αποθηκευθεί σε μία μνήμη καθ’όλη τη διάρκεια ζωής της. / --
150

Μοντελοποίηση και πειραματική εξομοίωση του μηχανισμού γήρανσης μνημών τεχνολογίας NAND

Σκλίας, Γεώργιος 06 May 2015 (has links)
Η συμπεριφορά των NAND Flash μνημών, της πιο επιτυχημένης τε- χνολογίας Non-Volatile μνημών σήμερα, αλλοιώνεται με την αύξηση των εγγραφών. Αυτή η διαδικασία, που ονομάζεται γήρανση, πέρα από μη ανα- στρέψιμη είναι και πολύ σημαντική για τον σχεδιασμό συστημάτων που χρησιμοποιούν NAND Flash μνήμες (π.χ. SSD), επειδή επηρεάζει την ΙΟ απόδοση και την αξιοπιστία του συστήματος. Τα πειράματα πάνω σε πραγ- ματικές NAND Flash μνήμες είναι χρονοβόρες και μη αναστρέψιμες δια- δικασίες, καθώς νέες εγγραφές στην μνήμη αυξάνουν την γήρανση και η συμπεριφορά του συστήματος αλλάζει. Σκοπός της παρούσας διπλωματικής εργασίας, είναι η ανάπτυξη ενός συστήματος που θα μπορεί να εξομοιώσει σε πραγματικό χρόνο και με με- γάλη ακρίβεια την συμπεριφορά NAND Flash μνημών με συνθήκες γή- ρανσης παραμετροποιημένες από τον χρήστη. Τα βασικά πλεονεκτήματα αυτής της προσέγγισης είναι τα ακόλουθα: η τεχνολογία που εξομοιώνεται μπορεί να χρησιμοποιηθεί υπό ίδιες συνθήκες γήρανσης για επαναληπτικά πειράματα και το ίδιο σύστημα μπορεί να χρησιμοποιηθεί για να συγκρίνει διαφορετικές τεχνολογίες μνημών υπό διαφορετικές συνθήκες γήρανσης χρησιμοποιώντας τις ίδιες ρυθμίσεις hardware. / The behavior of NAND Flash, the most successful non-volatile memory technology today, deteriorates as the number of write accesses increases. This process, known as aging, is not only irreversible but also critical for the design of systemsthat use NAND Flash (ie. Solid-State Drives), since it affects the system’s IO performance and the required overhead for achieving a specific level of reliability. Experimental characterization of NAND Flash-based systems during their whole lifetime is a time-consuming and non-repetitive process, since further programming cycles increase aging, and the system's behavior changes. In this work, we present the architecture and experimental resultsof a system that can be used to emulate in real-time and with high precision the behavior of NAND Flash memories underuser-defined aging conditions. The main advantages of this approach are the following: the emulated technology can be used under the same aging conditions for repetitive experiments and under different aging conditions using the same hardware setup.

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