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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.
11

A Escola Normal de Juiz de Fora: crises e permanências (1881-1911) / The Normal School of Juiz de Fora: crises and permanences (1881-1911)

Priscila Alves Ferreira 04 July 2013 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / A motivação apresentada nesta dissertação alimentou-se pela instabilidade evidenciada no processo de criação e na tentativa de consolidação da Escola Normal de Juiz de Fora. Sendo alvo de constantes críticas e debates, o papel da escola normal, assim como sua permanência, motivou propostas, reformas e manifestações, que envolveram não só o poder político, mas também a sociedade. Tais apontamentos foram observados tanto em periódicos da cidade, como o Jornal do Commercio e o Correio de Minas, quanto em documentos encontrados no Arquivo Público Mineiro, como relatórios de inspetores e correspondências de professores.Algumas das publicações presentes nesses periódicos expressaram e, de certa forma, mobilizaram a população a tomar atitudes contra a supressão da mesma, através de abaixo-assinados e representações enviadas ao governo do estado, muitas vezes enaltecendo não só a escola normal, mas principalmente a cidade de Juiz de Fora, considerada a principal da Zona da Mata mineira. Assim, foram mapeadas as discussões sobre a instituição, levantando questões sobre o posicionamento dos diferentes atores sociais acerca da instituição que, mesmo após sua supressão, não deixou de ser alvo de debates. Ainda, teceu-se algumas reflexões acerca da Reforma do Ensino Primário e Normal de João Pinheiro (1906), no que se refere ao ensino normal, mais especificamente no contexto juizforano. Para tanto, foram abordadas questões sobre a preferência da mulher para o magistério,o papel do professor e os institutos equiparados à Escola Normal Modelo de Belo Horizonte. Esse estudo concluiu que as determinações políticas não são produzidas apenas pelos discursos e decisões dos governantes, mas também são influenciáveis e podem ser modificadas por pressões de outros grupos sociais. Tais grupos sociais são formados por indivíduos com ideias e objetivos semelhantes, fazendo parte de um lugar e de uma posição social que os permitam circular e se manifestar em espaços que atinjam proporções significativas, como é o caso da imprensa. / The motivation presented in this dissertation was fed by the instability evident in the process of creation and in the attempt to consolidate the Normal School of Juiz de Fora. Being the target of constant criticism and debates, the role of the Normal School, as well as its permanence, motivated proposals, reforms and demonstrations, which involved not only political power, but also society. These notes were observed in both journals of the city, such as the Jornal do Commercio and Correio de Minas, as well as in documents found in the Mineiro Public Archives, such as reports of inspectors and teachers correspondences. Some of the publications present in these journals expressed and, in a way, mobilized the population to take action against its obliteration, through petitions and representations submitted to the State Government, often praising not only the Normal School, but mostly Juiz de Fora, considered the most important city of the Zona da Mata of Minas Gerais. Thus, the discussions about the institution were mapped, raising questions about the placement of the different social actors in regards to the institution which, even after its obliteration, did not cease to be the subject of debate. Furthermore, they wove some reflections on the JoãoPinheiros Primary and Normal Education (1906), in regards to normal teaching, specifically in the context of Juiz de Fora. Therefore, issues like the preference of women for teaching, the teacher's role and institutes equivalent to the Model Normal School of Belo Horizonte were addressed. This study concluded that the political determinations are not produced only by speeches and decisions of the rulers, but are also influenced and can be modified by pressure from other social groups. Such social groups are formed by individuals with similar goals and ideas, and are part of a place and a social position that allows them to move and manifest in spaces that reach significant proportions, as is the case of the press
12

Simulação estocástica de variáveis aleatórias Poisson correlacionadas: aplicação ao controle populacional do percevejo (Euschistus heros Fabricius) da soja (Glycine max L.) / Stochastic simulation for correlated Poisson random variables: application to population control bedbug (Euschistus heros Fabricius) soy (Glycine max L.)

Raphael Antonio Prado Dias 07 March 2014 (has links)
A simulação de dados que seguem distribuição de Poisson é essencial em muitas aplicações reais de várias áreas, tais como saúde, marketing, ciências agronômicas, entre outras em que os dados são contagens multivariadas. Métodos de simulação atuais sofrem de limitações computacionais e restrições à estrutura de correlação e, portanto, são raramente usados. Neste trabalho propôs-se uma modificação do método NORTA para gerar dados com distribuição Poisson multivariada a partir de uma distribuição normal multivariada com matriz de correlações e vetor de médias pré estabelecidos. Como as distribuições Normal multivariada e univariada e a distribuição Poisson univariada já estão implementadas em softwares estatísticos, inclusive no R, implementou-se algumas linhas de código. Mostrou-se que o método funciona bem e é altamente preciso na geração de dados multivariados com distribuição marginais de Poisson, para diferentes estruturas de correlações (negativas e positivas e variando os valores) e para altos e baixos valores de médias. Mostrou-se as vantagens práticas da simulação de dados de Poisson multivariada sobre a normal multivariada na detecção da taxa de falsos alertas de super populações de percevejos, evidenciando que simulações inadequadas podem levar a excesso de falsos alertas. Uma vez que os dados seguem distribuição Poisson multivariada, a taxa de falsos alertas pode ser maior do que a imaginada. Essa taxa pode ser estimada por um modelo ajustado. A mesma técnica pode ser aplicada em diversos problemas de várias áreas do conhecimento. / The simulation data that follow a Poisson distribution is essential in many real applications in various areas such as healthcare, marketing, agronomic sciences, among others that the data are multivariate counts. Current simulation methods suffer from limitations and constraints on computing correlation structure and are therefore seldom used. This paper proposed a modification of the NORTA method for generating data with multivariate Poisson distribution from a multivariate normal distribution with correlation matrix and vector of predetermined average. As the multivariate and univariate Normal distribution and univariate Poisson distribution are already implemented in statistical software, including R, was implemented just a few lines of code. It was shown that the method works well and is highly accurate in generating multivariate data with marginal Poisson distribution structures for different correlations (negative and positive values) and for high and low ?. Proved the practical benefits of the simulation data on the multivariate Poisson multivariate normal in the detection of super bugs populations, inadequate simulations can lead to excessive false alerts. Once the data are multivariate Poisson distribution, the rate of false alarms can be greater than the imagined. This rate can be estimated by an adjusted model. The same technique can be applied to many problems in various fields of knowledge.
13

Normal forms, connections and chains on nondegenerate CR manifolds.

January 2001 (has links)
Cheung Wing-chuen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 80-82). / Abstracts in English and Chinese. / Chapter 1 --- Introduction to CR manifolds --- p.6 / Chapter 1.1 --- Non-equivalence of real analytic hypersurfaces in C2 --- p.6 / Chapter 1.2 --- CR manifold and Levi form --- p.9 / Chapter 1.3 --- The real hyperquadrics --- p.16 / Chapter 2 --- Normal Forms --- p.22 / Chapter 2.1 --- Formal theory of normal forms --- p.22 / Chapter 2.2 --- Geometric theory of normal forms --- p.33 / Chapter 3 --- Connections and Curvatures --- p.45 / Chapter 3.1 --- Solution of the equivalence problem --- p.45 / Chapter 3.2 --- Geometric interpretation of the solution --- p.59 / Chapter 4 --- Chains --- p.65 / Chapter 4.1 --- Identification of the two definitions of chains --- p.65 / Chapter 4.2 --- Chain-preserving maps --- p.73 / Chapter 4.3 --- Some pathological behaviour of chains --- p.76 / Bibliography --- p.80
14

Examining relay ramp evolution through paleo-shoreline deformation analysis, Warner Valley fault, Oregon

January 2018 (has links)
acase@tulane.edu / Fault growth is often accomplished by linking a series of en echelon faults through relay ramps. A relay ramp is the area between two overlapping fault segments that tilts and deforms as the faults accrue displacement. The structural evolution of breached normal fault relay ramps remains poorly understood because of the difficulty in defining how slip is partitioned between the most basinward fault (known as the outboard fault, which includes the severed fault tip), the overlapping fault (inboard fault), and any ramp-breaching linking faults. Along the Warner Valley fault in south-central Oregon, two relay ramps displaying different fault linkage geometries are lined with a series of pluvial shorelines that record a Pleistocene paleolake regression. The inner edges of these shorelines act as paleo-horizontal datums that have been deformed by fault activity, and are used to measure relative slip variations across the relay ramp bounding faults. By measuring the elevation changes using a 10m digital elevation model (DEM) of shoreline inner edges, I estimate the amount of fault activity on severed fault tips. In order to attribute shoreline deformation to fault activity I identify shoreline elevation anomalies, where deformation exceeds a ± 0.3% window from normalized elevation values; this encompasses my conservative estimates of natural variability in the shoreline geomorphology and the error associated with the data collection. For each ramp-breaching fault style activity is concentrated near the fault linkage site. Even after a ramp is fully breached the severed fault tip temporarily retains some connectivity to the main fault segment. Severed fault tips along a mid-ramp breach tend to be more active than the severed fault tip at a footwall breach. Persistent fault activity along the entire severed fault tip is dependent on the position of the linkage. These results indicate that on the time scale of 104 years after linkage, severed fault tips persist as active structures and accommodate meaningful amounts of strain. / 1 / Christopher Samuel Young
15

Attention in normal aging and Alzheimer's disease

Corney, Patrick 26 January 2009
A large body of research has investigated various aspects of attention in normal aging and Alzheimers disease (AD). Most of the previous studies have shown that divided attention, the ability to attend to two tasks or stimuli simultaneously, declines in both normal aging and AD. In a recent study of attention, Baddeley, Baddeley, Bucks, and Wilcock (2001) reported findings that contrast with other divided attention research. Specifically, they found no effects of aging on divided attention. Taken in combination with their findings of age and AD effects on other aspects of attention, the authors concluded that age-equivalent results on divided attention tasks support the theory that attentional control should be viewed as a fractionated system. Study 1 considered methodological differences between the divided attention tasks used by Baddeley et al., and the tasks used by researchers who have reported age-related differences. Specifically, the effects of task difficulty on age effects were examined. Young, middle-aged, and older adults were compared on a dual-task procedure that combined a secondary visuomotor task (box joining) with a primary verbal task (month reciting) administered at two levels of difficulty. Results showed a significant Age x Task Difficulty interaction. That is, differences among age groups were proportionately greater in the difficult dual-task condition versus the easy condition, suggesting that age-related declines in divided attention may only be detected if tasks are sufficiently difficult.<p> Study 2 examined attention in normal aging and AD. Young adults, older adults, and early-stage AD patients were compared on tasks of selective attention, focal attention, and divided attention, with each task administered at two levels of difficulty. Similar Group x Task Difficulty interaction effects were detected for all attentional tasks, a finding which is more consistent with a general-purpose model than a fractionated model of attention. Study 3 considered attentional tasks from a clinical perspective. Specifically, the attentional tasks utilized in Study 2 were examined with respect to their ability to correctly classify individuals with early-stage AD and normal older adults. Findings showed that all attentional tasks successfully discriminated patients from cognitively healthy older adults, with one task of divided attention showing particularly impressive sensitivity and specificity. Findings of the three studies are discussed with regard to their implications for future research and clinical practice.
16

The Role of Chinese Normal Universities in the Professional Development of Teachers

Qi, Jie 31 August 2012 (has links)
The major purpose of the study was to analyze the role of the normal universities in China in the field of teacher professional development. In order to achieve this purpose, the following two questions guided this research: 1) What efforts are normal universities in China making in continuing teacher education? 2) What are the factors that support or inhibit normal universities in these endeavors? The research includes case studies of four Chinese normal universities as well as a comparison to the work of universities in Ontario, Canada. In-depth interviews were utilized as the major data collecting method, and document review was used as a supplementary method. The participants included university administrators, university teacher educators and government administrators. The study outlined the current state of normal universities’ work in the field of in-service teacher education by reviewing the larger policy context around teacher development in China and how it contributes to the development of this work. In addition, the study identified key issues and major challenges normal universities face in taking part in in-service teacher education system. The study found that government policy on in-service teacher education in China is currently dominating the work of provincial governments and normal universities. The training programs delivered by normal universities are often university-based, intensive teacher learning and result from contracts between universities and either central or provincial governments. Normal universities often feel poorly prepared in terms of institutional structure, promotion standards, and the number of well-qualified teacher training experts. Although willing to take an important position in the overall in-service teacher training system, normal universities lack confidence that they will be given consistent policy and financial support and are unclear about the direction of in-service teacher education reform in the future. Key findings of this study can be used to inform the role that Chinese Normal Universities might play in in-service teacher education that could lead to higher quality teaching and learning both at the university and school levels.
17

The Role of Chinese Normal Universities in the Professional Development of Teachers

Qi, Jie 31 August 2012 (has links)
The major purpose of the study was to analyze the role of the normal universities in China in the field of teacher professional development. In order to achieve this purpose, the following two questions guided this research: 1) What efforts are normal universities in China making in continuing teacher education? 2) What are the factors that support or inhibit normal universities in these endeavors? The research includes case studies of four Chinese normal universities as well as a comparison to the work of universities in Ontario, Canada. In-depth interviews were utilized as the major data collecting method, and document review was used as a supplementary method. The participants included university administrators, university teacher educators and government administrators. The study outlined the current state of normal universities’ work in the field of in-service teacher education by reviewing the larger policy context around teacher development in China and how it contributes to the development of this work. In addition, the study identified key issues and major challenges normal universities face in taking part in in-service teacher education system. The study found that government policy on in-service teacher education in China is currently dominating the work of provincial governments and normal universities. The training programs delivered by normal universities are often university-based, intensive teacher learning and result from contracts between universities and either central or provincial governments. Normal universities often feel poorly prepared in terms of institutional structure, promotion standards, and the number of well-qualified teacher training experts. Although willing to take an important position in the overall in-service teacher training system, normal universities lack confidence that they will be given consistent policy and financial support and are unclear about the direction of in-service teacher education reform in the future. Key findings of this study can be used to inform the role that Chinese Normal Universities might play in in-service teacher education that could lead to higher quality teaching and learning both at the university and school levels.
18

Attention in normal aging and Alzheimer's disease

Corney, Patrick 26 January 2009 (has links)
A large body of research has investigated various aspects of attention in normal aging and Alzheimers disease (AD). Most of the previous studies have shown that divided attention, the ability to attend to two tasks or stimuli simultaneously, declines in both normal aging and AD. In a recent study of attention, Baddeley, Baddeley, Bucks, and Wilcock (2001) reported findings that contrast with other divided attention research. Specifically, they found no effects of aging on divided attention. Taken in combination with their findings of age and AD effects on other aspects of attention, the authors concluded that age-equivalent results on divided attention tasks support the theory that attentional control should be viewed as a fractionated system. Study 1 considered methodological differences between the divided attention tasks used by Baddeley et al., and the tasks used by researchers who have reported age-related differences. Specifically, the effects of task difficulty on age effects were examined. Young, middle-aged, and older adults were compared on a dual-task procedure that combined a secondary visuomotor task (box joining) with a primary verbal task (month reciting) administered at two levels of difficulty. Results showed a significant Age x Task Difficulty interaction. That is, differences among age groups were proportionately greater in the difficult dual-task condition versus the easy condition, suggesting that age-related declines in divided attention may only be detected if tasks are sufficiently difficult.<p> Study 2 examined attention in normal aging and AD. Young adults, older adults, and early-stage AD patients were compared on tasks of selective attention, focal attention, and divided attention, with each task administered at two levels of difficulty. Similar Group x Task Difficulty interaction effects were detected for all attentional tasks, a finding which is more consistent with a general-purpose model than a fractionated model of attention. Study 3 considered attentional tasks from a clinical perspective. Specifically, the attentional tasks utilized in Study 2 were examined with respect to their ability to correctly classify individuals with early-stage AD and normal older adults. Findings showed that all attentional tasks successfully discriminated patients from cognitively healthy older adults, with one task of divided attention showing particularly impressive sensitivity and specificity. Findings of the three studies are discussed with regard to their implications for future research and clinical practice.
19

Bifurcations, Normal Forms and their Applications

Chen, Jian 19 May 2005 (has links)
The first part is a study of an ecological model with one herbivore and $N$ plants. The system has a new type of functional response due to the speculation that the plants compete with each other and have different levels of toxin which inhibit the herbivore's ability to eat up to a certain amount. We first derive the model mathematically and then investigate, both analytically and numerically, the possible dynamics for this model, including the bifurcation and chaos. We also discuss the conditions under which all the species can coexist. The second part is a study in the normal form theory. In particular, we study the relations between the normal forms and the first integrals in analytic vector fields. We are able to generalize one of Poincare's classical results on the nonexistence of first integrals in an autonomous system. Then in the space of 2n-dimensional analytic autonomous systems with exactly n resonances and n functionally independent first integrals, we obtain some results related to the convergence and generic divergence of the normalizations. Lastly we give a new proof of the necessary and sufficient conditions for a planar Hamiltonian system to have an isochronous center.
20

Geology of the McMillan Ranch in Mason, Texas: An Assessment of the Nature of Normal Faults in the Mason Area

Harper, Rebecca Anne 2011 August 1900 (has links)
Mason, Texas and the surrounding areas have been previously studied and mapped at small scales, showing the large normal faults that cut through the area. Many secondary faults exist close to the large faults, and are not mapped in previous studies because of the small scale of the maps. The large number of faults, when the smaller secondary faults are considered, makes Mason a good place for studying the nature of normal faults in this region and making generalizations about their nature. This thesis examines one of these faults, the McMillan Fault, and the secondary faults in its hanging wall at a large scale, in order to assess the nature of normal faults in the Mason area. The McMillan Ranch in Mason, Texas, was mapped at a scale of 1:7,000 using both traditional and digital mapping methods, to determine the lengths and displacements of each fault, and attempt to determine a length/displacement ratio which can be applied to all normal faults in this area. A single length/displacement ratio was not determined, just as in previous studies. This study determined that the normal faults in the area are planar, high angle normal faults with varying displacement amounts. As a result, observations determined that deformation in the hanging wall of normal faults exceeded the deformation in the footwalls of the same faults. The main fault on the McMillan Ranch is the McMillan Fault, and its shape is determined based upon the orientation of the subsidiary normal faults in its hanging wall. A detailed study of the geology of the McMillan Ranch and the surrounding area, including a geologic history of the area, geologic map and cross section, and stratigraphic descriptions including bed-by-bed descriptions, stratigraphic column, and thin sections of each unit was carried out as a preliminary step to perform analyses of the faults on the ranch. The presence of the McMillan Fault was already known, and the pasture that was chosen for this study was best represented at a scale of 1:7,000. At such a large scale, it was necessary to recognize precisely where in the stratigraphic section the mapper was located, as some subsidiary faults were recognized by beds missing, rather than entire units. The structural data gathered from the field convey the varying natures of faults, even within the same area, and support the conclusion that length alone is not sufficient to predict displacement value on a fault.

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