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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.
391

Estratégias e táticas nas visitações da inquisição portuguesa ao Brasil: o imaginário da teatralização da fé, primeiros regimentos e direito inquisitorial (1552 – 1620)

Pascoal, José Runivaldo Marques 31 August 2015 (has links)
Submitted by Maike Costa (maiksebas@gmail.com) on 2016-07-08T12:16:23Z No. of bitstreams: 1 arquivo total.pdf: 1957254 bytes, checksum: fede19224bb6003868ad6f9f76eb5c00 (MD5) / Made available in DSpace on 2016-07-08T12:16:23Z (GMT). No. of bitstreams: 1 arquivo total.pdf: 1957254 bytes, checksum: fede19224bb6003868ad6f9f76eb5c00 (MD5) Previous issue date: 2015-08-31 / From the cultural history perspective and through the comparative method this paper proposes that during visitations by the hole court in Bahia, Pernanbuco, Paraiba and Itamaracá states between the end of the sixteenth and early seventeenth century. “The representatives of faith” developed several strategies of advertisements that supported themselves in several symbolics mechanisms of visual or oral character to highlight a certain drama that has been able to change the social coexistence in colonial territories that was investigated in order to establish a control on religious beliefs and the settlers` moral behavior and, this way, to enable the confrontation of “offenders” behaviors that threatened the expected homogenization of the christianity dreamt by all. In this context of strong religious feelings, the edicts, the monitorio, the preparation of deocesan and inquisitorial visits, the cerimonies, the processions, the sermans of faith, the encouragement to the complaint and confession, the symbolic contained during public presentations, the exhibition of the sabenitos that was processed at the churches, the retualistic procedural and all kind of rituals have been gradually formed into an advertising instrument that by its turn has motivated the speech of “ forgiveness” and “mercy” spreaded by those who represented themselves as “heroes of christianity” the only ones who could cut with their “justice sword” the evil of heterodoxies and apply it according to 1552 and 1613 regulations, the established standards and duties, by transforming this way, the moment of their arrival and remaining in this places in a perfomance of faith that was able to give logical sense to the implemantation and relevance to their “discretionary justice” responsible for directing the sociability of relationships that should be ruled according to the dominant discourse by the “combat armed of faith” and “courage” in order to guarantee “ life after death” and the transcendental “reconnect” / Na perspectiva da História Cultural e através de estudo comparativo, esta dissertação propõe que durante as visitações executadas pelo Tribunal do Santo Ofício aos espaços da Bahia, Pernambuco, Paraíba e Itamaracá, entre o término do século XVI e início do XVII, os representantes da fé fomentaram diversas estratégias de propagandas que se apoiaram em diversos mecanismos simbólicos de caráter visual ou oral para pôr em destaque uma certa dramaturgia, que foi capaz de modificar o convívio social nos territórios coloniais os quais foram investigados para tentar se estabelecer nos mesmos uma vigilância sobre as crenças religiosas e as condutas morais dos colonos e, dessa maneira, possibilitar o enfrentamento dos comportamentos transgressores que ameaçavam à tão sonhada homogeneização da cristandade. Nesse contexto de forte sentimento religioso, os éditos, monitórios, a preparação das visitas diocesanas e inquisitoriais, as cerimônias, procissões, sermões da fé, o estímulo à denúncia e as confissões, a simbólica contida durante as apresentações públicas, a exposição dos sambenitos dos processados nas igrejas, a ritualística processual e toda a sorte de rituais se constituíram paulatinamente em instrumentos publicitários estimuladores do discurso do “perdão” e “misericórdia” disseminados pelos que se representavam como heróis da cristandade únicos que podiam cortar com o seu gládio da justiça, o mal das heterodoxias e aplicar, de acordo com os regimentos de 1552 e 1613, as normas e deveres estabelecidos, transformando desse modo, o momento de sua chegada e permanência nesses lugares numa espetacularização da fé, capaz de dar um sentido lógico para implementação e pertinência da sua justiça discricionária, responsável por direcionar as relações de sociabilidades que deviam ser pautadas, de acordo com os discursos dominantes, pelo combate armado de fé e coragem a fim de garantir a tão deseja vida após a morte e o religar transcendental.
392

Padroniza??o de testes para avalia??o do estado de mania e potencial anti-man?aco de um agonista do receptor NOP

Souza, Lisiane de Santana 13 March 2015 (has links)
Submitted by Automa??o e Estat?stica (sst@bczm.ufrn.br) on 2016-02-22T22:44:30Z No. of bitstreams: 1 LisianeDeSantanaSouza_DISSERT.pdf: 745201 bytes, checksum: 806e3c4a0c61a452eb082563d4b09ac0 (MD5) / Approved for entry into archive by Arlan Eloi Leite Silva (eloihistoriador@yahoo.com.br) on 2016-02-25T22:35:00Z (GMT) No. of bitstreams: 1 LisianeDeSantanaSouza_DISSERT.pdf: 745201 bytes, checksum: 806e3c4a0c61a452eb082563d4b09ac0 (MD5) / Made available in DSpace on 2016-02-25T22:35:00Z (GMT). No. of bitstreams: 1 LisianeDeSantanaSouza_DISSERT.pdf: 745201 bytes, checksum: 806e3c4a0c61a452eb082563d4b09ac0 (MD5) Previous issue date: 2015-03-13 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / O transtorno bipolar ? caracterizado pela disfun??o do humor, alternando entre epis?dios de mania/hipomania e depress?o, e sua fisiopatologia exata ainda continua indeterminada. A farmacoterapia do transtorno bipolar baseia-se na preven??o dos epis?dios de mania e depress?o atrav?s do uso de estabilizadores do humor. A nociceptina/orfanina FQ (N/OFQ) ? um heptadecapept?deo end?geno e agonista do receptor NOP, um receptor acoplado ? prote?na G do tipo inibit?ria. A N/OFQ e seu receptor desempenham uma s?rie de pap?is funcionais no organismo, e, entre eles, est? a modula??o de processos emocionais. Sabe-se que h? altera??o na concentra??o plasm?tica de N/OFQ em pacientes na fase depressiva e man?aca do transtorno bipolar e, por isso, presume-se que esse sistema teria algum papel na etiologia deste transtorno. Com rela??o ? mania, os modelos animais utilizados na pesquisa tendem a focar em apenas um aspecto do quadro man?aco, como a hiperatividade ou agressividade. Nos anos 60, foi proposto o teste do hole board, aparato provido de furos onde prioritariamente se mede nos animais um comportamento conhecido como ?imers?o de cabe?a? (head-dipping). Altos n?veis de head-dippings podem ser indicativos de neofilia, enquanto baixos n?veis poderiam ser reflexo de um comportamento do tipo ansioso. Como o aumento do comportamento explorat?rio e direcionado a objetivos s?o sintomas caracter?sticos dos quadros man?acos, este teste poderia oferecer subs?dios para a pesquisa deste transtorno. Deste modo, o presente trabalho foi dividido em 3 etapas e visa apresentar (1) a indu??o de um estado similar ao de mania promovido pela administra??o de ouaba?na, um inibidor da enzima Na+ /K+ -ATPase, em camundongos no campo aberto; (2) a padroniza??o do hole board como um teste para mensura??o de comportamentos do tipo man?acos; e (3) a investiga??o do efeito da N/OFQ na preven??o destes comportamentos no hole board. Para o desenvolvimento deste estudo, foram usados camundongos Swiss machos que participaram de apenas uma das etapas descritas acima e receberam um ou mais dos seguintes tratamentos, de acordo com a etapa: (1) ouaba?na, nas doses de 10-6 , 10-5 , 10-4 , 10-3 ou 10-2 M, intracerebroventricular (icv); (2) valproato de s?dio 300 mg/kg, intraperitoneal (ip); (3) valproato de s?dio 400 mg/kg, ip; (4) diazepam 1 mg/kg, ip; (5) metilfenidato 10 mg/kg, ip; e (6) N/OFQ nas doses de 0,1 ou 1 nmol, icv. Os resultados sugerem que o hole board ? um teste que pode ser usado para a avalia??o de quadros man?acos, atrav?s da an?lise de v?rios comportamentos do animal. Entretanto, n?o foi poss?vel padronizar o modelo da disfun??o da enzima Na+ /K+ -ATPase induzido pela administra??o de ouaba?na usando camundongos como sujeitos experimentais. Ainda, os dados sugerem que a N/OFQ, nas doses testadas, n?o ? eficaz na preven??o de um quadro de mania. Tomados em conjunto, os resultados apontam para uma nova abordagem na pesquisa da mania, atrav?s do uso do hole board. Entretanto, mais estudos precisam ser feitos a fim de comprovar o envolvimento do sistema da nociceptina/orfanina FQ na ocorr?ncia do transtorno bipolar. / Bipolar disorder is characterized by mood impairment, alternating between mania/hypomania and depression, and its exact pathophysiology is already unknown. The treatment of bipolar disorder is based on prevention of the manic and depressive episodes using mood stabilizers. Nociceptin/orfanin FQ (N/OFQ) is an endogenous heptadecapeptide which binds as an agonist to NOP receptor, which is a G-coupled inhibitory receptor. N/OFQ and its receptor modulate a lot of functions in the organism, including emotional processes. It is known that the plasmatic concentration of N/OFQ is altered in patients in both phases depressive and manic of bipolar disorder and it is assumed that this system has a role on the etiology of this disorder. Concerning mania, the animal models used in research tend to focus in an unique aspect of the manic behavior, as hyperactivity or agressivity. In the 60?s, the hole board test was proposed, and it consists of an apparatus with holes where a behavior known as head-dippings is measured. High levels of head-dippings are suggestive of neophilia, while low levels can be characteristic of an anxious-like behavior. As the increase of exploratory and goal-directed behavior are characteristics of manic behavior, this test could help in mania research. Thus, this work was organized in 3 steps and aims to: (1) investigate the induction of a manic-like state promoted by ouabain, a Na+/K+-ATPase inhibitor, in the mouse open field test; (2) set up the hole board as a test to measure manic-like behaviors; and (3) investigate the N/OFQ effects in prevention of this kind of behavior on hole board. Male Swiss mice were used in this study, and they take part of only one of the described steps. Depending on the step performed, mice received one or more of the following treatments: (1) ouabain 10-6 , 10-5 , 10-4 , 10-3 or 10-2 M, intracerebroventricular (icv); (2) sodium valproate 300 mg/kg, intraperitoneal (ip); (3) sodium valproate 400 mg/kg, ip; (4) diazepam 1 mg/kg, ip; (5) methylphenidate 10 mg/kg, ip; and (6) N/OFQ 0,1 or 1 nmol, icv. The results suggest that hole board can be used to evaluate a manic state, through analysis of different animal behaviors. However, it was not possible to standard the model of Na+ /K+ -ATPase dysfunction through ouabain administration in mice. Moreover, the data suggest that N/OFQ, at the doses tested, has not affected the methylphenidate-induced mania-like behavior. Taken together, the results point to a new approach of manic research, through the hole board using. However, more studies are necessary in order to verify the role of N/OFQ system on bipolar disorder.
393

Estudo da incerteza de medição na análise das tensões residuais através do método do furo cego

Pelizzari, Elisangela January 2013 (has links)
Para muitos componentes e estruturas de engenharia a determinação precisa do estado de tensões residuais presente é de fundamental importância para a avaliação de sua integridade estrutural. O método do furo cego (MFC) é um dos métodos mais difundidos para a medição de tensões residuais, no entanto, por se tratar de um ensaio relativamente complexo, a determinação da sua incerteza de medição apresenta uma série de dificuldades, as quais se refletem na inexistência de estudos na literatura que abordem esse assunto de forma completa. Este trabalho tem como objetivo a determinação da incerteza de medição do MFC englobando todas as fontes de incerteza em potencial do método. Para tanto, foi elaborado um procedimento envolvendo a determinação e caracterização das fontes de incerteza tanto na parte experimental como no tratamento matemático dos dados. A partir da caracterização das fontes de incerteza detectou-se como fator principal na determinação da incerteza o erro do operador, que foi possível através do desvio de repetitividade. A fonte de incerteza devido ao erro do operador foi a de determinação mais complexa e envolveu o projeto e a construção de uma máquina especialmente desenvolvida para a aplicação de um estado de tensões homogêneo e que permitisse medir com precisão as tensões residuais com o método do furo cego. Técnicas de medição de tensões residuais por difração de raios-X e monitoramento de tensão com extensometria de resistência elétrica foram utilizadas para a verificação da homogeneidade das tensões nas amostras. A metodologia se mostrou adequada, conduzindo a resultados que permitiram determinar com sucesso a incerteza de medição através de planilhas eletrônicas. / The characterization of the residual stress state of engineering components and structures is of fundamental importance for assessments of their structural integrity. The hole drilling method is one of the most commonly used methods; however, due to its relative complexity, quantifying its measurement uncertainties is not straightforward. It is a semi-destructive method, which means that multiple measurements cannot be repeated in a same location, and stress distributions mean that it is difficult to guarantee that a number of points in the same state will be available in a given volume. This study suggests a global uncertainty measurement which includes a study of repeatability related to the operator. This is thought to be novel in the existing literature. For this, a standard sample and a machine which guarantees a homogeneous stress distribution in the sample were developed. To ensure the homogeneity of the stresses, x-ray diffraction measurements were performed. The results obtained show good repeatability for different operators and good results for the uncertainty of measurements for the method.
394

Determinação de pressões em fossas de erosão a jusante de dissipadores tipo salto esqui / Pressures determination in scour holes downstream of ski jump dissipators

Buffon, Franco Turco January 2016 (has links)
Nesta dissertação estão apresentados os principais conceitos teóricos envolvidos na ação dos jatos formados em dissipadores tipo salto esqui sobre fossa de erosão pré-escavada, desde o trajeto do jato em sua fase aérea e em sua fase submersa, dando especial ênfase às pressões hidrodinâmicas e sua caraterização junto ao fundo da bacia. Para estudar experimentalmente a ação dos jatos nas bacias de dissipação, utilizou-se de um modelo físico de escala 1:100 construído no Laboratório de Obras Hidráulicas do IPH/UFRGS com ensaios de diferentes vazões e diferentes profundidades de fossas pré-escavadas. Os dados foram extraídos dos ensaios no modelo físico através de vasta instrumentação, utilizando-se comportas, pontas linimétricas, piezômetros, sensores de pressão, imagens e outros equipamentos. Foi realizada uma análise criteriosa dos dados gerados no modelo físico a partir das imagens do jato na sua trajetória aérea e no escoamento do jato em sua fase submersa, comparando os dados do modelo aos resultados obtidos por métodos tradicionais de cálculo. Também foram analisados os dados de pressão gerados durante os ensaios, sendo apresentados os resultados relativos às pressões médias e às pressões dinâmicas. As pressões dinâmicas observadas no modelo físico foram comparadas com as calculadas por meio de metodologia teórica abordada na bibliografia com a finalidade de avaliar a qualidade dessa metodologia para aplicação em projetos de engenharia, onde se observou grandes diferenças de magnitude da pressão quando em colchões rasos, e diferenças de distribuição de pressão ao longo do fundo da bacia de dissipação, principalmente quando em colchões profundos. No sentido de ajustar a metodologia aplicada, foi proposta a variação de parâmetros que regulam a forma do bulbo de pressões e a aplicação de um coeficiente de amortecimento de pressões, sendo que assim foi possível melhorar significativamente a distribuição e a magnitude das pressões calculadas devido à ação dos jatos no fundo da bacia de dissipação. Os resultados se mostram satisfatórios até determinada distância após o pico de pressão provocado pelo jato, sendo que após este ponto os efeitos de ressalto hidráulico prevalecem e devem ser pesquisados em estudos futuros. / In this dissertation are presented the main theorical concepts involved in the action of the jets formed in ski jump spillways on stilling basins type pre-excavated scour hole, from the path of the jet in its air stage and in his submerged phase, with particular emphasis on hydrodynamic pressures and its characterization by the bottom of the basin. To experimentally study the action of the jets in stilling basins, was used a physical model in scale 1:100 built in Hydraulic Works Laboratory of IPH/UFRGS with experiments of different flow rates and different depths of pre-excavated scour hole. The data were extracted from experiments on the physical model through extensive instrumentation, using gates, piezometers, pressure sensors, images and other equipment. A careful analysis of the data generated in the physical model from the jet images in your path through the air was performed and the flow of the jet in its submerged phase, comparing the model data to the results obtained by traditional methods of calculation. The pressure data generated during the tests and presented the results for the mean pressures and dynamic pressures were also analyzed. Dynamic pressures observed in the physical model were compared with those calculated by means of theoretical methods for the purpose of evaluating the quality of this methodology for use in engineering projects, where we observed large differences in magnitude of pressure when in shallow water beds, and diferences in pressure distribution over the stilling basin bottom, especially when in deep water beds. In order to adjust the applied methodology, it was proposed to change parameters governing the shape of the pressure bulb and the application of a pressure damping coefficient, and thus was possible to significantly improved the distribution and magnitude of the calculated pressures due to action of the jets in the stilling basin bottom. The results have been satisfactory up to a certain distance after the peak pressure caused by the jet, and after this point the hydraulic jump effects prevail and should be investigated in future studies.
395

Síntese de vistas em depht-image-based rendering (DIBR) / View synthesis with depth-image-based rendering (DIBR)

Oliveira, Adriano Quilião de January 2016 (has links)
Esta dissertação investiga soluções para o problema genérico de geração de vistas sintéticas a partir de um conjunto de imagens utilizando a abordagem Depth-Image-Based Rendering. Essa abordagem utiliza um formato compacto para a representação de imagens 3D, composto basicamente por duas imagens, uma colorida para a vista de referência e outra em tons de cinza com a correspondência de disparidade para cada pixel. Soluções para esse problema beneficiam aplicações como Free Viewpoint Television. O maior desafio é o preenchimento de regiões sem informação de projeção considerando o novo ponto de vista, genericamente denominados holes, além de outros artefatos como cracks e ghosts que ocorrem por oclusões e erros no mapa de disparidade. Nesta dissertação apresentamos técnicas para remoção e tratamento de cada uma das classes de potenciais artefatos. O conjunto de métodos propostos apresenta melhores resultados quando comparado com o atual estado da arte em geração de vistas sintéticas com o modelo DIBR para o conjunto de dados Middlebury, considerando-se as métricas SSIM e PSNR. / This dissertation investigates solutions to the general problem of generating synthetic views from a set of images using the Depth-Image-Based Rendering approach. This approach uses a compact format for the 3D image representation, composed basically of two images, one color image for the reference view and other grayscale image with the disparity information available for each pixel. Solutions to this problem benefit applications such as Free Viewpoint Television. The biggest challenge is filling in regions without projection information considering the new viewpoint, usually called holes, and other artifacts such as cracks and ghosts that occur due to occlusions and errors in the disparity map. In this dissertation we present techniques for removal and treatment of each of these classes of potential artifacts. The set of proposed methods shows improved results when compared to the current state of the art generation of synthetic views using the DIBR model applied to the Middlebury dataset, considering the SSIM and PSNR metrics.
396

Otimização do Infill para redução das incertezas em um depósito sintético de cobre / Infill optimization to reduce uncertainty in a copper ore synthetic deposit

Gustavo Zanco Ramos 19 September 2016 (has links)
A aquisição de novas informações de sondagem é realizada por intermédio do infill de furos de sonda e esta é uma prática utilizada em diversas etapas da exploração mineral. Métodos de otimização são largamente utilizados em várias fases e processos na vida da mina, por exemplo na otimização de cavas, na otimização do sequenciamento de lavra, entre outros. Contudo a utilização de métodos de otimização aplicados à locação de furos de inifill não é usual. Neste trabalho propõem-se utilizar a otimização matemática para melhorar a distribuição espacial dos novos furos, bem como para definir a quantidade adequada de furos a serem realizados. Métodos de otimização meta-heurísticos foram testados com o objetivo de minimizar duas funções objetivo que tratam das incertezas associadas à simulação dos dados, que são a soma da variância e a soma dos coeficientes de variação dos blocos simulados. O método que apresentou melhores resultados na otimização da função objetivo no menor tempo e custo computacional foi o método simulated annealing com resfriamento rápido e memória. Com base neste método de otimização comparou-se as funções objetivo propostas. Para efetuar a comparação amostraram-se os 11 furos definidos pela otimização para ambas as funções objetivo. O infill amostral foi realizado no corpo sintético e as comparações realizadas foram: a estatística descritiva - dos dados de infill comparados à população - e o gráfico Q-Q entre o e-type das simulações realizadas na base com infill e a população. A estatística descritiva do infill permitiu interpretar que a amostragem atualizada (soma das amostragens inicial e a nova) apresentou-se mais representativa do que a amostragem incial. Baseado no resultado dos gráficos Q-Q, a simulação calculada com o infill otimizando a minimização da soma dos coeficientes de variação apresentou maior aderência à população. / The acquisition of new drillhole information can be accomplished by the drill hole infill, a practice used in several steps of the mineral exploration. Optimization methods are widely used in several stages and processes of the mine life cycle, for example, mine pit optimization, mine scheduling optimization among others. However the optimization of drill hole infill locations are unusual. This work proposes the use of mathematical optimization to improve the spatial distribution and the number of the new drill holes to be made. Metaheuristics optimization methods were tested to minimize two objective functions that deal with the uncertainty associated to simulated data, the sum of the simulated blocks variance and the sum of the simulated blocks coefficient of variation. The best processing cost, processing time and results were obtained by simulated annealing method with fast cooling and memory for both objective functions. Based on this optimization method both proposed objective functions were compared. In order to perform the comparison 11 optimized drill holes locations by both objective functions were sampled. Sampling infill were done in the synthetic ore body and the made comparisons were: statistics - comparison between the infill data and population - and the QQ plot of the e-type statistics computed for simulation based on infill and population. Statistics for infill allowed to interpret that updated sample (the addition of new sampling in the initial data) was more representative than the initial sampling. Based on Q-Q plot the simulation computed for optimized infill location by the sum of the coefficient of variation minimization has more adherence to population.
397

Analysis of Black Hole attack on MANETs Using different MANET routing protocol

Ur-Rehman, Shoaib, Ullah, Irshan January 2010 (has links)
ABSTRACT Wireless networks are gaining popularity day by day, as users want wireless connectivity irrespective of their geographic position. There is an increasing threat of malicious nodes attacks on the Mobile Ad-hoc Networks (MANET). Black hole attack is one of the security threat in which the traffic is redirected to such a node that actually does not exist in the network. It’s an analogy to the black hole in the universe in which things disappear. MANETs must have a secure way for transmission and communication which is quite challenging and vital issue. In order to provide secure communication and transmission, researcher worked specifically on the security issues in MANETs, and many secure routing protocols and security measures within the networks were proposed. The scope of this thesis is to study the effects of Black hole attack in MANET using both Proactive routing protocol i.e. Optimized Link State Routing (OLSR) and Reactive routing protocol Ad-Hoc on Demand Distance Vector (AODV). Comparative analysis of Black Hole attack for both protocols is taken into account. The impact of Black Hole attack on the performance of MANET is evaluated finding out which protocol is more vulnerable to the attack and how much is the impact of the attack on both protocols. The measurements were taken in the light of throughput, end-to-end delay and network load. Simulation is done in Optimized Network Engineering Tool (OPNET). Previously the works done on security issues in MANET were based on reactive routing protocol like Ad-Hoc on Demand Distance Vector (AODV). Different kinds of attacks were studied, and their effects were elaborated by stating how these attacks disrupt the performance of MANET.
398

Analysis of Black Hole Attack on MANETs Using Different MANET Routing Protocols

ULLAH, IRSHAD, REHMAN, SHOAIB UR January 2010 (has links)
Wireless networks are gaining popularity to its peak today, as the users want wireless connectivity irrespective of their geographic position. There is an increasing threat of attacks on the Mobile Ad-hoc Networks (MANET). Black hole attack is one of the security threat in which the traffic is redirected to such a node that actually does not exist in the network. It’s an analogy to the black hole in the universe in which things disappear. The node presents itself in such a way to the node that it can attack other nodes and networks knowing that it has the shortest path. MANETs must have a secure way for transmission and communication which is quite challenging and vital issue. In order to provide secure communication and transmission, researcher worked specifically on the security issues in MANETs, and many secure routing protocols and security measures within the networks were proposed. Previously the works done on security issues in MANET were based on reactive routing protocol like Ad-Hoc On Demand Distance Vector (AODV). Different kinds of attacks were studied, and their effects were elaborated by stating how these attacks disrupt the performance of MANET. The scope of this thesis is to study the effects of Black hole attack in MANET using both Proactive routing protocol i.e. Optimized Link State Routing (OLSR) and Reactive routing protocol Ad-Hoc On Demand Distance Vector (AODV). Comparative analysis of Black Hole attack for both protocols is taken into account. The impact of Black Hole attack on the performance of MANET is evaluated finding out which protocol is more vulnerable to the attack and how much is the impact of the attack on both protocols. The measurements were taken in the light of throughput, end-to-end delay and network load. Simulation is done in Optimized Network Engineering Tool (OPNET).
399

Current transport in hydrogenated amorphous silicon nitride

Morgan, B. A. January 2000 (has links)
A defect band is formed in hydrogenated amorphous silicon nitride (a-SiNx:H) due to current stressing of the material. This gives rise to an increase in conductivity, referred to as current induced conductivity. This thesis investigates the current transport mechanisms that occur in the induced defect band, by comparing the temperature dependence of the conductivity of several sets of a-SiNx:H thin film diodes. These sets were systematically current stressed to different levels with one set remaining unstressed. Samples with energy gaps of 2.06 eV and 2.28 eV were considered. We show that around room temperature a modified Poole-Frenkel description of conduction (i.e. field enhanced hopping of carriers via charged defect states) provides a good fit to the data. Using this model the activation energy of current transport was calculated and shown to depend on the material band gap. Data fitting to the Poole-Frenkel model provided further support for the field-assisted hopping mechanism. Previous investigations had suggested that the defect band resides in the lower half of the band gap, so that current transport through the defect band was then expected to be due to the movement of holes, in a manner consistent with Poole-Frenkel conduction. By considering samples grown on p-type and n-type substrates, we demonstrated that transport was indeed the result of the movement of holes through the defect states within the induced defect band. At lower temperatures the experimental data is poorly described by a modified Poole-Frenkel type process, so further mechanisms were considered, including variable-range hopping and nearest-neighbour hopping. Due to the similar nature and slight temperature dependence of each process, differentiating between the two mechanisms proved difficult. However, other factors such as the temperature range and defect density favoured variable-range hopping transport. By assuming this form of low temperature hopping transport, conduction through the defect-band of the a-SiNx:H, could then be convincingly explained over the entire temperature range from 320 K to 20 K in terms of two dominant transport mechanisms, Poole-Frenkel conduction and variable-range hopping.
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The Torus Does Not Have a Hyperbolic Structure

Butler, Joe R. 08 1900 (has links)
Several basic topics from Algebraic Topology, including fundamental group and universal covering space are shown. The hyperbolic plane is defined, including its metric and show what the "straight" lines are in the plane and what the isometries are on the plane. A hyperbolic surface is defined, and shows that the two hole torus is a hyperbolic surface, the hyperbolic plane is a universal cover for any hyperbolic surface, and the quotient space of the universal cover of a surface to the group of automorphisms on the covering space is equivalent to the original surface.

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