Spelling suggestions: "subject:"lld"" "subject:"dld""
71 |
Circuitos embebidos aplicados a equipos médicosGómez Cornejo Campana, David Yusseff January 2011 (has links)
This thesis describes the design guidelines from two medical teams, electrocardiogram and pulse oximetry using embedded logic circuitry such as FPGA and microcontrollers, digital filters used to filter the signals obtained from analog converters to digital, graphic obtaining the data is displayed in a graphic display GLCD, and has an interface to send data to a PC through a port USB 2 at full speed.
The digital filters used are FIR filters, these filters are chosen to be linear and time invariant, developed with 40 coefficients FIR filters, these filters were implemented in the FPGA, use a FPGA that has implemented only 20 multipliers For the implementation we used the VHDL language and algorithmic state machines in order to control the 20 boxes and get the 40 products.
Filtered data in the stage of the FPGA, are taken to a microcontroller that is responsible for managing the data, can lead to a graphic display GLCD, and so we can see the signal and obtained values or you can send the data to a PC right through USB port and software right through it can see the graphics on the PC.
|
72 |
La présence de la politique dans les médias au Japon : l'ingérence de la politique et les stratégies médiatiques du pouvoir face à l'évolution des médias / Presence of politics in the media in Japan : the interference of politics and the media strategies in the power facing the evolution of the mediaKawada, Yutaka 13 June 2014 (has links)
Dans la société d’aujourd’hui, les médias sont indispensables et très importants pour les activités des citoyens. Les médias se sont développés avec les évolutions des systèmes sociaux et économiques aussi bien qu'avec les avancées technologiques. Les médias ont été utilisés par les autorités pour le contrôle de la société pendant la période de la guerre quand la liberté d’expression était sévèrement limitée. Cependant, après l’époque de l’Occupation, le Japon a gagné le statut de régime démocratique où les médias peuvent s’exprimer librement. Le système de 1955, qui a assuré la domination d'un parti du parlement ( le PLD ) sans interruption pendant 38 ans, a été rendu possible par les conditions propres à la situation politique au Japon. Par contre, plus tard, les médias ont largement contribué à la chute de ce système politique solide ayant duré si longtemps. Désormais, les médias ont tendance à exercer une grande influence sur la politique. D’autre part, les autorités ont commencé à prendre des mesures pour le contrôle des médias en leur faveur, ce qui est une ingérence dans les médias et une pression considérable sur leurs activités d’expression. Dans une situation où la liberté des médias est limitée, les citoyens, en revanche, ont réagi face aux autorités avec des moyens nouveaux, et la relation entre les médias et la politique devient plus essentielle pour nous de nos jours. / Nowadays in the society, the media are essential and very important for the activities of people. The media have developed with the evolution of social and economic systems as well as technological advancements. The media were used by the authorities to control the society during the war, when the freedom of expression was severely limited. However, after the period of the occupation, Japan won the state of a democratic regime, where the media could enjoy freedom of expression. The 1955 system, where domination by one party of Parliament ( the LDP ) continued without interruption for 38 years, was created by the unique conditions of politics in Japan. However, later, the media contributed greatly to the fall of this strong political system with long duration. Now the media have a tendency to exert a great influence on politics. On the other hand, the authorities began to take measures to control the media in favor of their policy, which is interference in the media and made considerable pressure on their expression activities. Under the situation where media freedom is limited, the people, however, reacted against the authorities with new means and the relationship between media and politics is becoming more serious for us today.
|
73 |
The CB1R system within the nucleus accumbens of vervet monkeysKucera, Ryan 04 1900 (has links)
No description available.
|
74 |
Técnicas de reconfigurabilidade dos FPGAs da família APEX 20K - Altera. / Reconfigurability technics for the FPGAs of family APEX 20K - Altera.Teixeira, Marco Antonio 26 August 2002 (has links)
Os dispositivos lógicos programáveis pertencentes à família APEX 20K, são configurados no momento da inicialização do sistema com dados armazenados em dispositivos especificamente desenvolvidos para esse fim. Esta família de FPGAs possui uma interface otimizada, permitindo também que microprocessadores os configure de maneira serial ou paralela, síncrona ou assíncronamente. Depois de configurados, estes FPGAs podem ser reconfigurados em tempo real com novos dados de configuração. A reconfiguração em tempo real conduz a inovadoras aplicações de computação reconfigurável. Os dispositivos de configuração disponíveis comercialmente, limitam-se a configurar os FPGAs apenas no momento da inicialização do sistema e sempre com o mesmo arquivo de configuração. Este trabalho apresenta a implementação de um controlador de configuração capaz de gerenciar a configuração e reconfiguração de múltiplos FPGAs, a partir de vários arquivos distintos de configuração. Todo o projeto é desenvolvido, testado e validado através da ferramenta EDA Quartus II, que propicia um ambiente de desenvolvimento integrado de projeto, compilação e síntese lógica, simulação e análise de tempo. / The APEX 20K programmable logic devices family, are configured at system power-up with data stored in a specific serial configuration device. This family of FPGAs contain an optimized interface that permits microprocessors to configure APEX 20K devices serially or in parallel, and synchronously or asynchronously. After configured, it can be reconfigured in-circuit by resetting the device and loading new data. Real-time changes lead to innovative reconfigurable computing applications. The commercial available configuration devices limit to configure the APEX 20K devices only on the system power-up and always with the same configuration data file. This work shows a configuration controller implementation that can manage the configuration and reconfiguration of several FPGAs from multiple configuration files. The entire project is developed, tested and validated through the EDA tool Quartus II, that provide a integrated package with HDL and schematic design entry, compilation and logic synthesis, full simulation and worst-case timing analysis.
|
75 |
Optimisation de films minces électrochromes à base d'oxyde de nickelPark, Dae-Hoon 08 June 2010 (has links) (PDF)
Dans la perspective du développement de vitrages électrochromes « en milieu protonique », des films minces électrochromes à coloration anodique, à base d'oxyde de nickel, ont été synthétisés et caractérisés. Afin d'améliorer la durabilité des films minces à base de NiO, trois approches ont été envisagées. (i)Des films d'oxyde de nickel et d'oxyde mixte nickel/lithium, déposés par PLD (Pulsed Laser Deposition). Nous avons étudié l'influence du lithium sur les propriétés physico-chimiques (‘amorphisation..), et les caractéristiques électrochromes (électrochimique-optique) en milieu aqueux KOH 1M. (ii) Des films composites, préparés par voie chimique (solution), constitués d'une phase amorphe (en diffraction des Rayons X), de composition Ti1-xZnxO2-x□x, englobant des cristallites de NiO de ~ 5 nm de diamètre. Les courbes voltampérométriques révèlent que seule la phase NiO est électrochimiquement active, mais la phase amorphe, grâce aux lacunes anioniques neutres, □x, renforce la tenue mécanique des films déposés sur les substrats FTO/verre. Il s'ensuit que ces films composites sont plus stables au cyclage, en milieu aqueux KOH 1M, que leurs homologues TiO2/NiO. (iii) Des films minces d'oxyde de nickel dopés par du carbone, préparés par une voie sol-gel originale, présentant une remarquable tenue en cyclage (> 25000 cycles en milieu aqueux KOH 1M), jamais observée jusqu'ici pour NiO.
|
76 |
In Situ Transmission Electron Microscopy Characterization of NanomaterialsLee, Joon Hwan 1977- 14 March 2013 (has links)
With the recent development of in situ transmission electron microscopy (TEM) characterization techniques, the real time study of property-structure correlations in nanomaterials becomes possible. This dissertation reports the direct observations of deformation behavior of Al2O3-ZrO2-MgAl2O4 (AZM) bulk ceramic nanocomposites, strengthening mechanism of twins in YBa2Cu3O7-x (YBCO) thin film, work hardening event in nanocrystalline nickel and deformation of 2wt% Al doped ZnO (AZO) thin film with nanorod structures using the in situ TEM nanoindentation tool. The combined in situ movies with quantitative loading-unloading curves reveal the deformation mechanism of the above nanomaterial systems.
At room temperature, in situ dynamic deformation studies show that the AZM nanocomposites undergo the deformation mainly through the grain-boundary sliding and rotation of small grains, i.e., ZrO2 grains, and some of the large grains, i.e., MgAl2O4 grains. We observed both plastic and elastic deformations in different sample regions in these multi-phase ceramic nanocomposites at room temperature.
Both ex situ (conventional) and in situ nanoindentation were conducted to reveal the deformation of YBCO films from the directions perpendicular and parallel to the twin interfaces. Hardness measured perpendicular to twin interfaces is ~50% and 40% higher than that measured parallel to twin interfaces, by ex situ and in situ, respectively.
By using an in situ nanoindentation tool inside TEM, dynamic work hardening event in nanocrystalline nickel was directly observed. During stain hardening stage, abundant Lomer-Cottrell (L-C) locks formed both within nanograins and against twin boundaries. Two major mechanisms were identified during interactions between L-C locks and twin boundaries. Quantitative nanoindentation experiments recorded during in situ experiments show an increase of yield strength from 1.64 to 2.29 GPa during multiple loading-unloading cycles.
In situ TEM nanoindentation has been conducted to explore the size dependent deformation behavior of two different types (type I: ~ 0.51 of width/length ratio and type II: ~ 088 ratio) of AZO nanorods. During the indentation on type I nanord structure, annihilation of defects has been observed which is caused by limitation of the defect activities by relatively small size of the width. On the other hand, type II nanorod shows dislocation activities which enhanced the grain rotation under the external force applied on more isotropic direction through type II nanorod.
|
77 |
Study Of Pulsed Laser Ablated Barium Strontium Titanate Thin Flims For Dynamic Random Access Memory ApplicationsSaha, Sanjib 08 1900 (has links)
The present study describes the growth and characterization of pulsed laser ablated Bao.sSro.sTiOs (BST) thin films. Emphasis has been laid on the study of a plausible correlation between structure and property in order to optimize the processing parameters suitably for required application. An attempt has been made to understand the basic properties such as, origin of dielectric response, charge transfer under low and high-applied electric fields across the BST capacitor and finally the dielectric breakdown process.
Chapter 1 gives a brief introduction on the application of ferroelectric thin films in microelectronic industry and its growth techniques. It also addresses the present issues involved in the introduction of BST as a capacitor material for high-density dynamic random access memories. Chapter 2 outlines the motivation for the present study and briefly outlines the research work involved.
Chapter 3 describes the experimental procedure involved in the growth and characterization of BST thin films using pulsed laser ablation technique. Details include the setup design for PLD growth, material synthesis for the ceramic targets, deposition conditions used for thin film growth and basic characterizations methods used for study of the grown films.
Chapter 4 describes the effect of systematic variation of deposition parameters on the physical and electrical properties of the grown BST films. The variation in processing conditions has been found to directly affect the film crystallinity, structure and morphology. The change observed in these physical properties may also be correlated to the observed electrical properties. This chapter summarizes the optimal deposition conditions required for growing BST thin films using a pulsed laser ablation technique.
Microstructure of BST films has been categorized into two types: (a) Type I structure, with multi-grains through the film thickness, for amorphous as-grown films after high temperature annealing (exsitu crystallized), and (b) columnar structure (Type II) films, which were as-grown well-crystallized films, deposited at high temperatures.
The ac electrical properties have been reviewed in detail in Chapter 5. Type I films showed a relatively lower value of dielectric constant (e ~ 426) than Type II films with dielectric constant around 567. The dissipation factors were around 0.02 and 0.01 for Type I and Type II films respectively. The dispersion in the frequency domain characteristics has been quantitatively explained using Jonscher's theory. Complex impedance spectroscopy employed showed significant grain boundary response in the case of multi-grained Type I films while negligible contribution from grain boundaries has been obtained in the case of columnar grained Type II BST films. The average relaxation time r obtained from the complex impedance plane plots show almost three orders higher values for Type I films. The obtained results suggest that in multi-grained samples, grain boundary play a major role in electrical properties. This has been explained in accordance to a model proposed on the basis of depleted grains in the case of Type I films where the grain sizes are smaller than the grain boundary depletion width.
Chapter 6 describes the dc leakage properties of the grown BST thin films and the influence of microstructure on the leakage properties. It was evident from the analysis of the graph of leakage current against measurement temperature, that, the observed leakage behavior in BST films, can not be attributed to a single charge transport mechanism. For Type I films, the Arrhenius plot of the leakage current density with 1000/T exhibits different regions with activation energy values in the range of 0.5 and 2.73 for low fields (2.5kV/cm). The activation energy changes over to 1.28 eV at high fields (170 kV/cm). The obtained values agree well with that obtained from the ac measurements, thus implying a similarity in the origin of the transport process. The activation energy value in the range of 0.5 eV is attributed to the electrode/film Schottky barrier, while the value in the range of 2.73 eV is due to deep trap levels originating from Ti+3 centers. The value in the range of 1.28 eV has been attributed to oxygen vacancy motion. Similar results have been obtained from the Arrhenius plot of the leakage current for Type II films. In this case, only two different activation energy values can be identified in the measured temperature and applied electric field range. At low fields the activation energy value was around 0.38 eV while at high fields the value was around 1.06 eV. These values have been identified to be originating from the electrode/film Schottky barrier and oxygen vacancy motion respectively. Thus a complete picture of the charge transport process in the case of BST thin film may be summarized as comprising of both electronic motion as well as contribution from oxygen vacancy motion.
The effect of electrical stress on the capacitance-voltage (C-V) and the leakage current has been analyzed in Chapter 7. From the change in the zero bias capacitance after repeated electron injection through the films the values of the electronic capture cross-section and the total trap density for Type I and II films have been estimated. The results showed higher values for Type I film in comparison to Type II films. The difference has been attributed to the presence of grain boundaries and a different interface in the case of Type I films when compared to Type II films where the absence of grain boundaries is reflected in the columnar microstructure. A study of the time-dependent-dielectric-breakdown (TDDB) characteristics under high fields for Type I and Type II films showed higher endurance for Type I film. On the other hand space-charge-transient characteristics have been observed in the case of Type II films at elevated temperature of measurement. Mobility and activation energy values extracted from the transient characteristics are found to be in the range of 1 x 10~12 cm2 /V-sec and 0.73 eV respectively, suggesting a very slow charge transport process, which has been attributed to the motion of oxygen vacancies. An overall effect of electrical stress suggested that oxygen vacancy motion can be related to the observed resistance degradation and TDDB, which has been further enhanced by the combination of high temperature and high electric fields.
Chapter 8 deals with the effect of intentional doping in the BST films. The doping includes Al at the Ti-site, Nb in the Ti-site and La at the Ba/Sr-site. The effect of doping was observed both on the structure and electrical properties of the BST films. Acceptor doping of 0.1 atomic 7c Al was found to decrease the dielectric constant as well as the leakage current. For higher concentration of acceptor-dopant, the leakage current was found to increase while showing space-charge-transient in the TDDB characteristics, again suggesting the effect of increased concentration of oxygen vacancies. Donor doping using 2 atomic % La and Xb significantly improved the leakage as well as the TDDB characteristics by reducing the concentration of oxygen vacancies. A further procedure using graded donor doping in the BST films exhibits even better leakage and TDDB properties. An unconventional, graded doping of donor cations has been carried out to observe the impact on leakage behavior, in particular. The leakage current measured for a graded La-doped BST film show almost six orders of lower leakage current in comparison to undoped BST films, while endurance towards breakdown has been observed to increase many-fold.
Chapter 9 highlights the main findings of the work reported in this thesis and lists suggestions for future work, to explore new vistas ahead.
|
78 |
Multiferroic hexagonal HoMnO3 filmsKim, Jong-Woo 18 January 2010 (has links) (PDF)
The fundamental properties of hexagonal multiferric HoMnO3 films have been thoroughly investigated. The films are grown by pulsed laser deposition on Y:ZrO2(111) substrates. High quality epitaxial HoMnO3 films of 25 { 1000 nm thickness were successfully prepared. The film properties are compared to those of single-crystals.
The magnetization measurements revealed that the films show a deviating magnetic behavior from the single-crystals in several ways. For instance, the films have a weakened antiferromagnetic Ho3+ order confirmed from magnetic susceptibility. The difierences are likely to be related to the modified (mostly larger) lattice parameters of films. An approximate phase diagram in comparison with the single-crystal's one is constructed. For multiferroicity investigations, Second Harmonic Generation
(SHG; in collaboration with the group of M. Fiebig) has been employed. By SHG, the ferroelectric polar order of the films is obviously confirmed. The ferroelectric switching at room temperature could be clearly demonstrated, whereas leakage of films requires generally a more sophisticated approach. / Die fundamentalen Eigenschaften von hexagonalen multiferroischen HoMnO3 Schichten
werden eingehend untersucht. Die dünnen Schichten wurden mittels gepulster
Laserdeposition auf Y:ZrO2(111)-Substraten gewachsen. Hochwertige epitaktische
HoMnO3-Dünnschichten von 25 { 1000 nm Dicke wurden erfolgreich hergestellt. Die
Dünnschichteigenschaften werden mit denen von Einkristallen verglichen. Die Magnitisierungsmessungen
ergeben, dass die dünnen Schichten ein von den Einkristallen
in verschiedener Weise abweichendes magnetischen Verhalten zeigen. Zum Beispiel
haben die dünnen Schichten eine abgeschwächte antiferromagntetische Ho3+ Ordnung,
die durch die magnetische Suszeptibilität bestätigt wird. Die Unterschiede
sind wahrscheinlich auf die veränderten (meistens grösseren) Gitterparameter der
dünnen Schichten zurückzuführen. Ein Phasendiagramm wird zum Vergleich mit
Einkristallen konstruiert. Durch Second Harmonic Generation (SHG; in Zusammenarbeit
mit der Gruppe von M. Fiebig) wird die ferroelektrische Ordnung der dünnen
Schichten eindeutig bestätigt. Das ferroelektrische Umschalten bei Raumtemperatur
kann eindeutig nachgewiesen werden, wobei durch den Leckstrom der dünnen Schichten
allgemein eine detailliertere Vorgehensweise benötigt wird.
|
79 |
Synthèse et Caractérisation de poudres et couches minces de SrSn₁₋ₓ Ti ₓ O₃Menezes de Oliveira, André Luiz 07 October 2013 (has links) (PDF)
Le stannate (SrSnO3) et le titanate de strontium (SrTiO3) sont des oxydes de type pérovskite, de structures orthorhombique (Pbnm) et cubique (Pm3m), respectivement. Ces matériaux ont reçu beaucoup d'attention ces dernières années en raison de leurs propriétés physiques et chimiques intéressantes conduisant à différents types d'applications technologiques. Pour ces raisons, ces deux matériaux ont été combinés pour obtenir la solution solide de SrSn1-xTixO3, sous forme de poudres et couches minces. Au niveau des poudres, la solution solide a présenté des transitions de phases successives allant d'une structure orthorhombique à tétragonale puis cubique avec l'augmentation de la quantité de Ti4+ dans le système. Ces transitions ont été observées par affinement Rietveld des spectres de diffraction des rayons X et confirmées par spectroscopie Raman. Ces différentes structures cristallines ont conduit à des propriétés différentes de photoluminescence dans le spectre visible, l'émission variant d'une région de basse énergie vers les régions de plus haute énergie avec l'augmentation de Ti4+ dans la structure (structure orthorhombique (SrSnO3), tétragonale (SrSn0,75Ti0,25O3) à cubique (SrSn0,50Ti0,50O3, SrSn0,25Ti0,75O3 et SrTiO3). Ces émissions sont probablement favorisées par différents types de défauts formés dans le gap d'énergie de ces matériaux. Par ailleurs, les couches minces ont montré différents types de croissance qui ont été fortement influencés par la nature cristalline du substrat, la composition des films ainsi que par la méthode de dépôt utilisée (dépôt par voie chimique en solution - CSD - et dépôt par ablation laser pulsé - PLD). Les films minces déposés sur silice sont polycristallins (croissance aléatoire des cristallites), les couches sur saphir-R (Al2O3-012) sont également polycristallines mais avec une orientation préférentielle (h00) quand préparées par PLD (croissance texturée), excepté SrTiO3 qui est épitaxié avec une rotation de 45º par rapport au plan du substrat de saphir-R. Tous les films déposés sur LAO (LaAlO3-100) sont épitaxiés (h00) quelque soit la méthode de dépôt. De plus, les caractéristiques morphologiques et les propriétés photocatalytiques des films ont également été fortement influencées par ces mêmes paramètres cités précédemment. Concernant les propriétés photocatalytiques, les films préparés par la méthode CSD ont été plus efficaces que ceux obtenus par PLD et les couches de compositions plus riches en Sn4+ ont été plus actives face à la photodégradation du colorant Remazol jaune or, l'efficacité maximale étant observée pour la couche polycristalline de SrSnO3 obtenue par CSD avec un pourcentage de dégradation et de décoloration d'environ 55 et 90 %, respectivement. Le type de croissance des films de SrSnO3 préparés par les deux méthodes de dépôt a aussi montré une forte influence sur la photodégradation du colorant, les couches polycristallines d'orientation aléatoire obtenues sur silice étant plus efficaces que les texturées, elles-mêmes plus efficaces que les couches épitaxiales.
|
80 |
A utilização de instrumentos derivativos na gestão de riscos associada à contratação de energia elétrica por grandes consumidoresHonorato, Elaine Fridman 16 June 2010 (has links)
Submitted by Cristiane Shirayama (cristiane.shirayama@fgv.br) on 2011-05-24T13:09:28Z
No. of bitstreams: 1
61080100065.pdf: 2231348 bytes, checksum: 235b121ee6f62ddc94f7bcdc52256691 (MD5) / Approved for entry into archive by Gisele Isaura Hannickel(gisele.hannickel@fgv.br) on 2011-05-24T13:42:08Z (GMT) No. of bitstreams: 1
61080100065.pdf: 2231348 bytes, checksum: 235b121ee6f62ddc94f7bcdc52256691 (MD5) / Approved for entry into archive by Gisele Isaura Hannickel(gisele.hannickel@fgv.br) on 2011-05-24T13:42:43Z (GMT) No. of bitstreams: 1
61080100065.pdf: 2231348 bytes, checksum: 235b121ee6f62ddc94f7bcdc52256691 (MD5) / Made available in DSpace on 2011-05-24T13:43:07Z (GMT). No. of bitstreams: 1
61080100065.pdf: 2231348 bytes, checksum: 235b121ee6f62ddc94f7bcdc52256691 (MD5)
Previous issue date: 2010-06-16 / No Brasil, os contratos firmados entre geradores e grandes consumidores são registrados na Câmara de Comercialização de Energia que é responsável por contabilizar as diferenças entre o consumo contratado e o consumo verificado. Essas diferenças são negociadas ao Preço de Liquidação das Diferenças, o PLD. Este preço apresenta, como uma de suas principais características, o fato de ser volátil, pois está relacionado ao volume de água disponível para a geração de energia elétrica, o que é algo dependente das condições meteorológicas (no Brasil aproximadamente 80% da geração é proveniente de fontes hidráulicas).
|
Page generated in 0.0279 seconds