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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.
31

Detecção e correção de perdas de ciclos para dados GPS de tripla frequência /

Mendonça, Caio Henrique Chrisóstomo January 2019 (has links)
Orientador: Daniele Barroca Marra Alves / Resumo: A observável fase da onda portadora é utilizada quando se deseja obter alta acurácia no posicionamento por sistemas globais de navegação por satélite. Mas, esta observável pode sofrer perdas de ciclos durante o rastreamento do sinal. Uma perda de ciclo é uma descontinuidade de um número inteiro de ciclos na fase da onda portadora, causada por uma perda temporária de rastreamento do sinal pelo receptor. Assim, as perdas de ciclos devem ser detectadas e corrigidas para que se obtenha posicionamento acurado. Diversos métodos foram desenvolvidos com esse objetivo. Algo que também vem sendo amplamente estudado é a detecção das perdas de ciclos nos novos sinais GPS. O advento da terceira frequência disponibilizada a partir da modernização do GPS também deve ser explorado. Na presente pesquisa buscou-se estudar os diferentes métodos de detecção e correção de perdas de ciclos e implementar o mais adequado para o posicionamento de alta acurácia no Brasil. Foram selecionadas duas metodologias para fim de detecção e correção, sendo a primeira baseada no método das triplas diferenças (TD) clássico e a segunda baseada no método de sequência de combinações lineares. Além disso, foi proposta uma terceira metodologia para melhoria do método das TD. Foram realizados dois experimentos, sendo o primeiro realizado com dados simulados e o segundo com dados reais em período de alta atividade ionosférica, e para ambos os casos foram considerados dois cenários: linha de base curta e linha de base lo... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Carrier phase observable are used in high accuracy positioning by global navigation satellite systems. However, the carrier phase measurement may suffer cycle slips during signal tracking. A cycle slip is a discontinuity of an integer number of cycles in the phase observable, caused by a temporary loss of lock in the receiver carrier tracking loop. Thus, cycle slips must be detected and corrected in order to obtain accurate positioning. Several methods were developed for this purpose. Something that has also been studied is the detection of cycle slip in the new GPS signals. The advent of the third frequency available from the GPS modernization. Should be explored in the context of cycle slip detection and correction. In the present research the different cycle slip detection and correction methods were studied and t the most suitable for the high accuracy positioning in Brazil was implemented. Two methodologies were selected for the purpose of this research, the first one based on the classical triple difference (TD) method and the second based on the linear combination sequence method. In addition, a third methodology was proposed to improve the TD method. Two experiments were performed, the first one being carried out with simulated data and the second with real data in the period of high ionospheric activity, and for both cases two scenarios were considered: short baseline and long baseline. For simulated short baseline data, the classical TD method, the proposed TD metho... (Complete abstract click electronic access below) / Mestre
32

Research on the institutions of law on the The laws and decrees of the second year"¡Bthe Bamboo Slips of Zhangjiashan in the Eary Han Dynasty

Zhou, Mei-hwa 22 February 2010 (has links)
In this paper, to write, mainly based on Hubei Jingzhou Han Tomb No. 247 of The laws and decrees of the second year"¡Bthe Bamboo Slips of Zhangjiashan in the Eary Han Dynasty Empress Lu years (186BC) promulgated the "The laws and decrees of the second year". And these systems, do in depth. While many of these systems inherited from Qin, but also in the history of the early Han dynasty and the associated changes in state policy, under which such an amendment and gain. In addition to the time of the early Han Dynasty inherited the Qin, " Registration of Residents " and " The System of Granting Homestead ", but also because of the unified emerging empire, no longer need to use Qin "of dollars in the first grant Jue," The System of Granting Homestead, but to set the succession after the system, military medals Jue system has become extremely important to establish the household registration system supporting measures. So, the early Han Dynasty all the people's economic rights and social well-being, they are all related and the title of nobility class. In addition, even the preparation of the results of Wu is not only related to people, security and home management, also affected the litigation system, and even to sit, and even the limits of regional action. A number of related management measures, they must meet for us. Rather special is that the "The laws and decrees of the second year"Lane set a lot of bearing on women's rights law, women enjoy a number of special treatment; even the servants, there are also benefits in the slave girl slave components. "The laws and decrees of the second year" domain inside the official system should not only permit the " Shiwu System " the existence of, and its importance in the history of philology, but also presents the official system, the superiority of the domain. This with the "Shuo Wen Jie Zi ¡E order" than right, more found that "The laws and decrees of the second year".
33

Language Production In A Typological Perspective: A Corpus Study Of Turkish Slips Of The Tongue

Erisen, Ibrahim Ozgur 01 June 2010 (has links) (PDF)
The main purpose of this study is to establish a Turkish slips of the tongue (SOT) corpus and make typological comparisons with English, French and German corpora. In the first part of the study, a slips of the tongue corpus has been created. 85 podcast recordings were analyzed and 53 SOT errors were found. SOT errors were extracted from the podcasts and these audio clips were combined with their spectrograms in a flash video. Classification of SOT errors were carried out with respect to linguistic units involved, type of error, and repair behavior. In this study it is hypothesized that Turkish will have more morphological errors due to agglutination, and Turkish will have less phonological errors as vowel harmony will function as an extra control mechanism. Classification of the SOT errors with respect to linguistic units that are involved shows that 54.27% of the errors are phonological, 16.98% of errors are morphological, 13.21% of errors are lexical and 7.55% errors are phrasal. The classification with respect to error type shows that 26.42% of errors are anticipations, 30,19% of errors are perseverations, 18.87% errors are substitutions and 7.56% of errors are blends. There is a difference in the percentages of errors as compared to the other corpora. Turkish has more morphological and phonological errors. Also the data shows that there are more perseverations than anticipations, similar to German. Typological comparisons with other languages suggests that the difference in the ratio might be caused by the SOV sentence structure rather than agglutination. The first hypothesis was therefore confirmed partly. However, the second hypothesis was not supported. Vowel harmony did not function as a control mechanism on the phonological well-formedness of the utterance. Rather, it seems to be located at the level of morpho-phonology in the lexicon proper. Turkish having more phonological errors might also be related with a higher demand on working memory because of the head-final SOV sentence structure. In order to be able to draw more reliable conclusions the size of the Turkish SOT database needs to be increased.
34

Modes normaux des oscillations de la phase supraconductrice dans des chaînes de jonctions Josephson / Normal modes of superconducting phase oscillations in Josephson junction chains

Nguyen, Van Duy 05 November 2018 (has links)
Le sujet de thèse est une étude théorique des modes normaux d’oscillations plasma dans des chaînes de jonctions Josephson supra-conductrices. Les propriétés de ces modes normaux peuvent être contrôlés en choisissant une modulation spatiale appropriée de paramètres des jonctions le long de la chaîne et/ou un couplage approprié à l'environnement extérieur. Le travail théorique au sein du LPMMC se fait en étroite collaboration avec l'équipe expérimentale"Cohérence Quantique" à l'Institut Néel. Les problèmes spécifiques étudiés dans la thèse sont : modélisation détaillée du couplage des modes normaux à l'environnement pour leur caractérisation dans une expérience de transmission de micro-ondes, dissipation intrinsèque des oscillations du plasma à cause de quasi-particules hors équilibre, l'optimisation de la structure spatiale de la chaîne de jonctions Josephson pour son utilisation en tant qu'une super-inductance. / The subject of thesis is a theorerical study of normal modes of plasma oscillations in superconducting Josephson junction chains. The properties of these normal modes can be controlled by choosing an appropriate spatial modulation of the junction parameters along the chain and/or an appropriate coupling to the external environment. The theoretical work at LPMMC is performed in a close collaboration with the experimental Quantum Coherence group at Néel Institute. The specific problems studied in this thesis are : detailed modeling of the normal mode coupling to the environment for probing them in a microwave transmission experiment, intrinsic dissipation of plasma oscillations due to the presence of non-equilibrium quasi-particles, optimization of the spatial structure of the Josephson junction chain for its use as a super-inductance.
35

Laminage asymétrique de l'alliage de magnésium AZ31 / Structural and textural design of metallic alloys rolled by non conventional way

Forget, Mathilde 08 February 2013 (has links)
L’alliage de magnésium AZ31 présente une très faible densité. Cette caractéristique en fait un matériau apprécié pour la conception de structures légères. La limitation principale de son utilisation industrielle est sa mauvaise formabilité et ce en raison de la texture cristallographique des tôles qui s’avère être peu adaptée aux procédés de mise en forme tel que l’emboutissage. Cette texture résultant du laminage initial, l’ambition de ce travail est de la modifier en utilisant la technique de laminage asymétrique et de mesurer l’impact de cette voie sur la formabilité de l’alliage. Il a été montré que l’asymétrie, produite par un différentiel de vitesses de rotation des cylindres du laminoir, induit systématiquement de fortes instabilités plastiques sous forme de bandes de cisaillement. Des techniques de cartographie sur microscope électronique en transmission (ACOM) et à balayage (EBSD) ainsi que des analyses de texture par DRX ont été utilisées pour analyser les mécanismes physiques concourant à l’émergence de cette instabilité. Il résulte de cette analyse que l’asymétrie du laminage provoque une forte activité du système de glissement basal que ne compense ni les autres systèmes ni le maclage. Ceci conduit à une localisation marquée de la déformation plastique et à la ruine du matériau. / The low density of the magnesium alloy AZ31 makes it valuable for low weight components. The main limitation for industrial applications is the poor formability of sheets during deep drawing type processing. This is linked to the fibre crystallographic texture resulting from rolling. The objective of the present work is to modify the sheet texture through asymmetrical rolling. It has appeared that the asymmetry promoted by monitoring the roll speeds separately induces plastic instabilities through shear banding. The physical mechanisms involved in the instability were analysed with the help of orientation imaging techniques on transmission electron (ACOM/TEM) and scanning electron (EBSD/SEM) microscopes as well as with X-ray measurements. It is concluded that the shear resulting from the asymmetry in roll speeds promotes a dramatic increase of basal slip that neither twinning nor the activities of other slip systems are able to compensate. Such activity induces strain localisation and premature failure of the material.
36

Aproveitamento dos rejeitos da agroindústria de leite no município de Nossa Senhora da Glória/Semi-árido de Sergipe : caracterização e perspectivas de desenvolvimento sustentável

Costa, Antônio Wilson Macedo de Carvalho 08 March 2005 (has links)
The industrialization of the milk in the Sergipe semi-arid presents, nowadays, several kinds of cheese as main product, despising as slips many components with high nutritious value, provoking, beyond the economical loss, an environmental aggression. This study presents two integrations focus: (1) the technological question, with the characterization of the milk agriculture-industry slips, with the purpose of identifying economical and technological possibilities of utilization of the components of rejected nutritious value; and (2) the environmental question of these slips utilization, with the purpose of decreasing the environmental impacts and then guaranteeing the region development. Considering the context of the Nossa Senhora da Glória county, characterized as farming subsistence, the possibility of adapting the industrialization process with the social-economicalenvironmental questions will allow a more including social scope, promoting the improvement of the region life quality, as long as the milk industrialization process presents, in the technological question, considerable losses and environment impacts proportional, needing urgently of consolidated development alternatives in the principles of sustentation. The slips characterization, in this study, is made by means of physicchemistry and microbiological assays. The economical losses are calculated in function of the load and average productions of the agriculture-industries, considering their slips production, with the purpose of characterizing the agriculture-industries inside the context and suggesting alternatives of development, reducing the environmental impacts and allowing the sustainable development of the Sergipe semi-arid. / A industrialização do leite no semi-árido de Sergipe apresenta, atualmente, como principal produto, diversos tipos de queijo, desprezando vários componentes de alto valor nutritivo, na forma de rejeitos, provocando, além da perda econômica, uma agressão ambiental. Este estudo apresenta dois focos integrados: (1) a questão tecnológica, com a caracterização dos rejeitos da agroindústria de leite, com o objetivo de identificar possibilidades econômicas e tecnológicas de aproveitamento dos constituintes de valor nutritivo descartados; e (2) a questão ambiental do aproveitamento desses rejeitos, com o objetivo de minimizar os impactos ambientais de forma a garantir o desenvolvimento sustentável da região. Considerando o contexto do Município de Nossa Senhora da Glória, caracterizado como de subsistência agropecuária, a possibilidade de compatibilizar o processo de industrialização com as questões sócio-econômico-ambientais permitirá um alcance social mais abrangente, promovendo a melhoria da qualidade de vida da região, uma vez que o processo de industrialização do leite apresenta, na questão tecnológica, perdas consideráveis e proporcionais impactos ambientais, necessitando, urgentemente, de alternativas de desenvolvimento alicerçadas nos princípios da sustentabilidade. A caracterização dos rejeitos, neste estudo, é efetuada através de análises fisico-químicas e microbiológicas. As perdas econômicas são calculadas em função do porte e da produção média das agroindústrias, considerando sua geração de rejeitos, com a finalidade de caracterizar as agroindústrias de forma contextualizada, sugerindo alternativas de desenvolvimento, reduzindo os impactos ambientais e permitindo o crescimento sustentável do semi-árido de Sergipe.
37

Slips or errors? : A study of the grammatical mistakes in Swedish pupils' written production of English

Jonsson, Elina January 2015 (has links)
Grammar is an important aspect of language learning and is thus of concern in language teaching as well. This study sets out to investigate the kinds of grammatical mistakes Swedish secondary school pupils make in their written production of English and the possible causes behind these different mistakes. Forty essays from pupils in year nine have been used to study the phenomenon of frequently occurring mistakes and their causes, and the salient mistakes have been quantatively and qualitatively accounted for in the study.      Common mistakes found in the material were subject-verb concord mistakes, mistakes involving plural nouns, incorrect article usage as well as problems using prepositions correctly. Interlingual transfer, i.e. negative transfer from the pupils’ L1, proved to be one significant factor causing mistakes in the material. However, other causes could be traced as well, such as intralingual transfer for example.      Consequently, the findings of this study point in the direction of areas which need specific attention in English L2 learning in Swedish classrooms. Thus, the study contributes with valuable insights for English teacher and teacher trainees to consider in their future practice.
38

Positioning in GNSS-challenged environments : design framework, algorithms and technologies / Positionnement en environnements contraints : conception, algorithmes et technologies

Lu, Ye 17 September 2015 (has links)
Tandis que les humains explorent la nature sans relâche, ils font également attention à être plus conscients d'eux-mêmes, à mieux connaître ce qui les entourent, et, par exemple, à être informés de leurs positions, vitesses, ou trajectoires où qu'ils se trouvent. Les systèmes de positionnement par satellites (GNSS) ont fourni une manière de le faire à l'extérieur, devenant un assistant indispensable pour nous. Après le succès de GPS et GLONASS, Galileo et BeiDou sont actuellement en cours de déploiement, offrant plus de choix pour le positionnement autonome ou assisté. Toutefois, les signaux GNSS sont vulnérables aux obstacles: il n'y a presque pas de service GNSS à l'intérieur des bâtiments, dans les tunnels, ou dans les parkings souterrains; la continuité des services de positionnement par satellites n'est toujours pas assurée dans les "canyons urbains". Afin de faire face à ce problème, cette thèse est consacrée au positionnement en environnements contraints (où le GNSS n'est pas disponible), en y incluant la conception, les algorithmes et les technologies correspondantes. Un état de l'art est élaboré sur les systèmes de positionnement à radio ou à l'inertie. Parmi les technologies possibles, la discussion ne se limite pas à l'approche basée sur GNSS, mais elle est centrée sur cette dernière à cause de ses avantages et aussi de l’implication profonde de notre groupe de recherche dans ce domaine. Nous avons, d'une part, étudié la possibilité ainsi que les limites du positionnement avec une précision centimétrique en déployant notre système Repealite (i.e. un système de positionnement à l'intérieur d'une base des émetteurs GNSS spéciaux); et proposé, d'autre part, une méthode de localisation en groupe d'objets dynamiques communicants. Cette méthode procède d'une problématique délicate que l'on rencontre dans les approches GNSS, qu'est la détermination de la position initiale du récepteur. On montre en quoi elle permet également d'aller au-delà de la portée des approches classiques GNSS / While the human beings explore the nature tirelessly, they also put significant concerns to be aware of themselves, to know better of the circumstances, and to be informed with their precise positions, velocities, trajectories, and so on, in local environments. The Global Navigation Satellite Systems (GNSS) have provided an efficient method to do so outdoors, and have already become an indispensable assistant of many people. After the success of GPS and GLONASS, Galileo and BeiDou are currently under deployment, offering more choices of the independent or collaborative positioning. However, the GNSS signal is vulnerable to obstructions: almost no GNSS services are available inside buildings, tunnels, or underground parkings; the services are not always coherent in urban canyons. In order to address this problem, this thesis is dedicated to the design frameworks for the positioning in GNSS-challenged environments, as well as the corresponding algorithms and technologies. A brief survey of the latest radio-based and inertial positioning/tracking systems is provided. Among the feasible technologies, the discussion is centered on but not limited to the GNSS-based approach, which is due to the inherited advantages of this approach and also the deep engagement of our research group in this domain. We have, on one hand, explored the possibility and limitations on the centimeter-accuracy positioning with our Repealite system (i.e. a GNSS-base indoor positioning system with specific features); on the other hand, a method of batch localization for the nodes in a network of dynamic communicating objects is proposed, which is originated from an issue of the GNSS-based approach - the resolution of the receiver initial point, but then it goes beyond the scope of the “classical” GNSS-based approach
39

An Investigation into Type, Severity, and Cost of Injuries in the Automotive Repair Sector: Overall and by Age

Adkins, Ecstasy D. January 2014 (has links)
No description available.
40

Superconductive Effects in Thin Cluster Films

Grigg, John Antony Hugh January 2012 (has links)
In this thesis, the superconductive and superresistive properties of thin percolating films of lead nanoclusters are presented. The samples were created by depositing clusters from an inert gas aggregation cluster source onto substrates held at either room temperature or 10K. Observations of the characteristic behaviours of the samples were made through R(T ) and V (I) measurements. Several interesting features were observed - smooth and discrete steps in the R(I) curves, hysteresis between increasing and decreasing bias currents, and non-zero resistances at superconducting temperatures. Explanations are proposed in terms of theoretical models of several phenomena - phase slips, phase slip centres and hotspots - which have seen little prior application to percolating systems in literature.

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