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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.
151

Kinematic Constraints on Tremor and Slow Slip in Cascadia and Implications for Fault Properties

Krogstad, Randy 21 November 2016 (has links)
Subduction zone fault processes range from tsunami-generating megathrust events to aseismic creep along the deeper portions of the fault. Episodic tremor and slow slip (ETS) represents the transition between these two regimes, where slip occurs at semi-regular recurrence intervals of months-to-years. These events are also accompanied by low frequency earthquakes, referred to as tremor. The study of ETS in Cascadia has been made possible by the enhancement of large-scale seismic and geodetic networks. In this dissertation, I use a range of geodetic and seismic observations at sub-daily to decadal time scales to investigate the kinematic behavior of individual ETS events, as well as the long-term behavior of the ETS zone and its relationship with the updip seismogenic zone. In Cascadia, current seismic hazard maps use the ETS zone as the downdip limit of rupture during future megathrust events. In Chapter II, I utilize uplift rates derived from 80 years of leveling measurements to explore the possibility that long-term strain accumulation exists near the ETS zone. The uplift rates are consistent with a region of 10-20% locking on the updip side of the ETS zone. The lack of associated topography indicates that the accumulated strain must be released during the megathrust cycle. The correlation of tremor and slip in Cascadia suggests there is an inherent relationship between the two. In Chapter III, I develop a method for using tremor as a proxy for slip to assess the spatial relationship of tremor and slip. I compare predictions of tremor-derived slip models to results from static inversions of GPS offsets by modeling slip based on the density of tremor. These comparisons suggest that the correlation of tremor and slip is variable along strike and along dip. In Chapter IV, I explore how borehole strainmeters can improve our resolution of slip on the plate interface. I incorporate strainmeters into joint, time-dependent kinematic inversions with GPS data. The temporal resolution of strainmeters provides improved constraints when deriving time-dependent slip estimates during slow slip events, allowing us to better image the kinematics of slow slip. This dissertation includes previously published and unpublished material.
152

"A revolução está no prato"

Schneider, Kamila Guimarães January 2015 (has links)
Dissertação (mestrado) - Universidade Federal de Santa Catarina, Centro de Filosofia e Ciências Humanas, Programa de Pós-Graduação em Antropologia Social, Florianópolis, 2015. / Made available in DSpace on 2016-04-19T04:03:05Z (GMT). No. of bitstreams: 1 338084.pdf: 2561244 bytes, checksum: 6a126bed59342f8f2d6933088ad708f4 (MD5) Previous issue date: 2015 / A presente dissertação consiste em um estudo etnográfico juntamente com participantes de um movimento social internacional chamado Slow Food, com o objetivo de vivenciar, descrever e analisar os tipos de redes de interação social que se apresentam no Movimento. Primeiramente irei realizar uma contextualização histórica e estrutural do movimento, assim ver como os participantes do movimento internacional se adaptam para fazer parte do Slow Food e como criam uma base ao incentivo de uma cadeia curta de produção e consumo de alimentos e comidas locais e regionais. Meu percurso etnográfico inicia-se com os grupos locais do movimento que se localizam em Florianópolis ? SC, partindo para as interações estabelecidas nas regiões do Estado de Santa Catarina, na região Sul do Brasil, chegando a suas redes nacionais e as questões internacionais e globais. A metodologia aplicada ao trabalho foi a etnografia multisituada, por meio da observação participante e uma imersão de um ano e meio de contatos cotidianos. Para isso frequentei reuniões, encontros e eventos que o movimento apoiou ou ofereceu. Participei destes eventos tanto pessoalmente como por intermédio virtual. Tive como mediadores do campo meios audiovisuais, em que documentei alguns dos eventos. Para conseguir atingir o objetivo proposto busco no estilo de vida dos participantes do Movimento Slow Food cinco eixos mais comentados e discutidos pelos participantes: educação, ecogastronomia, risco, prazer e tempo.<br> / Abstract : This dissertation consists of an ethnographic study with participants of an international social movement called Slow Food, in order to experience, describe and analyze the types of networks of social interaction that arise in the movement. First I will present a historical and structural context of the movement, thus indicating how the participants of the international movement adapt to join the network and how they support a short chain of production and consumption of local and regional food. My ethnographic route begins with the local movement groups that are located in Florianópolis - SC, heading towards the interactions established in the regions of the State of Santa Catarina, in The South Region of Brazil, reaching their national networks and international and global issues. The methodology used to work was the multi-sited ethnography, through participant observation and immersion of a year and a half of regular contacts. I attended meetings and events supported or held by the movement. I attended these events either in person or by virtual means. I had audiovisual means as aids in the field, resulting in footage of some events. In order to achieve my goals I describe the lifestyle of the participants of the Slow Food movement based on the five main axes discussed by the participants: education, eco-gastronomy, risk, pleasure and time.
153

Acoustic emission-based diagnostics and prognostics of slow rotating bearings using Bayesian techniques

Aye, S.A. (Sylvester Aondolumun) January 2014 (has links)
Diagnostics and prognostics in rotating machinery is a subject of much on-going research. There are three approaches to diagnostics and prognostics. These include experience-based approaches, data-driven techniques and model-based techniques. Bayesian data-driven techniques are gaining widespread application in diagnostics and prognostics of mechanical and allied systems including slow rotating bearings, as a result of their ability to handle the stochastic nature of the measured data well. The aim of the study is to detect incipient damage of slow rotating bearings and develop diagnostics which will be robust under changing operating conditions. Further it is required to explore and develop an optimal prognostic model for the prediction of remaining useful life (RUL) of slow rotating bearings. This research develops a novel integrated nonlinear method for the effective feature extraction from acoustic emission (AE) signals and the construction of a degradation assessment index (DAI), which is subsequently used for the fault diagnostics of slow rotating bearings. A slow rotating bearing test rig was developed to measure AE data under variable operational conditions. The proposed novel DAI obtained by the integration of the PKPCA (polynomial kernel principal component analysis), a Gaussian mixture model (GMM) and an exponentially weighted moving average (EWMA) is shown to be effective and suitable for monitoring the degradation of slow rotating bearings and is robust under variable operating conditions. Furthermore, this study integrates the novel DAI into alternative Bayesian methods for the prediction of RUL. The DAI is used as input in several Bayesian regression models such as the multi-layer perceptron (MLP), radial basis function (RBF), Bayesian linear regression (BLR), Gaussian mixture regression (GMR) and the Gaussian process regression (GPR) for RUL prediction. The combination of the DAI with the GPR model, otherwise, known as the DAI-GPR gives the best prediction. The findings show that the GPR model is suitable and effective in the prediction of RUL of slow rotating bearings and robust to varying operating conditions. Further, the models are also robust when the training and tests sets are obtained from dependent and independent samples. Finally, an optimal GPR for the prediction of RUL of slow rotating bearings based on a DAI is developed. The model performance is evaluated for cases where the training and test samples from cross validation approach are dependent as well as when they are independent. The optimal GPR is obtained from the integration or combination of existing simple mean and covariance functions in order to capture the observed trend of the bearing degradation as well as the irregularities in the data. The resulting integrated GPR model provides an excellent fit to the data and improvements over the simple GPR models that are based on simple mean and covariance functions. In addition, it achieves a near zero percentage error prediction of the RUL of slow rotating bearings when the training and test sets are from dependent samples but slightly different values when the estimation is based on independent samples. These findings are robust under varying operating conditions such as loading and speed. The proposed methodology can be applied to nonlinear and non-stationary machine response signals and is useful for preventive machine maintenance purposes. Keywords: acoustic emission, Bayesian linear regression, Bayesian techniques, covariance function, data-driven, degradation assessment index, diagnostics, experience-based, exponentially weighted moving average, Gaussian mixture model, Gaussian mixture regression, Gaussian process regression, integration, mean function, model-based, multi-layer perceptron, polynomial kernel principal component analysis, prognostics, radial basis function, remaining useful life. / Thesis (PhD)--University of Pretoria, 2014. / lk2014 / Mechanical and Aeronautical Engineering / PhD / unrestricted
154

Cinemas of Endurance

Cottrel, Adam 04 December 2017 (has links)
Cinemas of Endurance begins by questioning the way in which critics and scholars have addressed art cinema over the last decade, specifically the films referred to as “slow cinema.” These films have garnered widespread attention since the start of the 21st century for how they deploy what many believe to be anachronistic and redundant formal techniques, often discussed in terms of nostalgia and pastiche. This dissertation argues that these films have been unfairly couched within this discourse that largely judges their validity based on their stylistic similarities to the art cinema of the 1960s and 1970s. Breaking from this direction, this project proposes we take these films and their aesthetic seriously, not for stubbornly refuting the prevailing formal trends in filmmaking, but for how it creates a critical optic that grants us a greater capacity to recognize some of the most prevailing social, political, and economic issues of the last decade. Further, by using stylistic techniques that can often register as out of place, or protracted, these films can help us to understand the way our physical, mental, and affective coordinates have shifted in this historical moment. Each chapter of this dissertation takes an exemplary film from this subset of art cinema and addresses how the aesthetic works against established modes of viewing to render visible modalities of life that often escape critical ire because they are expected. This project relies on the theories and methodologies of film and media studies, aesthetic theory, realism, materialism, accelerationism, cultural studies, continental philosophy, and political philosophy. The films and filmmakers analyzed include: The Limits of Control (2009), dir. Jim Jarmusch; Ossos (1997), In Vanda’s Room (2000), and Colossal Youth (2006), dir. Pedro Costa; Dogville (2003), dir. Lars von Trier; and, 2046 (2004), dir. Wong Kar-wai.
155

Tunable Slow and Fast Light Generation and the Applications in Microwave Photonics

Shahoei, Hiva January 2014 (has links)
In this thesis, new techniques to generate slow and fast light are proposed and investigated. The use of the slow and fast light for microwave photonics applications is also investigated. This thesis consists of four parts. In the first part, the generation of slow and fast light based on fiber Bragg gratings (FBGs) is studied. Two techniques are proposed. In the first technique, slow and fast light is generated based on a linearly chirped fiber Bragg grating (LCFBG); and in the second technique, slow and fast light is generated based on a tilted fiber Bragg grating (TFBG). Theoretical analysis is performed which is verified by experiments. In the second part, the applications of FBG-based slow and fast light in microwave photonics are studied. These applications include all-optical tunable microwave frequency multiplication, tunable microwave chirped pulse generation, tunable phase shifting, tunable fractional order differentiation, and tunable microwave photonic filtering. In the third part, the generation of slow and fast light based on microring resonators (MRRs) is studied. Novel methods to obtain continuously tunable slow to fast light are proposed and experimentally demonstrated by using a silicon-on-insulator (SOI) MRR with MMI (multi-mode interference) couplers, and a high-contrast Ge-doped silica-on-silicon (SOS) MRR. In the fourth part, the applications of the MRR-based slow and fast light in microwave photonics are studied. These applications include all-optical tunable fractional order differentiation, and tunable fractional order Hilbert transformation.
156

Slow Light Effects in Photonic Integrated Circuits with Application to Microwave Photonics

Lloret Soler, Juan Antonio 09 July 2012 (has links)
Esta tesis doctoral tiene como objetivo el diseño y la implementación de dispositivos ópticos novedosos capaces de realizar tareas de procesado de señales de rediofrecuencia, concretamente en las bandas de microondas y milimétricas, explotando para ello efectos de luz lenta que tienen lugar sobre algunos medios físicos que presentan características especiales. Con este propósito, se han investigado estructuras basadas en tecnología de semiconductor en guiaonda, además de estructuras de naturaleza resonante sobre circuitos en silicio y compuestos híbridos fabricados con materiales activos pertenecientes a los grupos III-V sobre silicio. En concreto, se han prouestos diferentes circuitos ópticos capaces de desarrollar tareas propias de desfasador y retardadeo verdadero de banda ancha para señales de radiofrecuncia. El comportamiento de dichos circuitos ópticos bajo estudio se ha caracterizado mediante modelado teórico, quedando éstos adecuadamente validados a través de resultados experimentales. En primer lugar, se han llevado a cabo estudios concernientes a la degradación producida por ruido en estructuras desfasadores formadas por amplificadores ópticos de semiconductor. Como resultado, se ha propuesto una nueva estructura que ha revertido en un rendimiento optimizado en términos de ruido sin que ello suponga una alteración en su funcionnalidad básica como desfasador. Esta estructura desfasadora ha sido el elemento clave en el ensamblado de un filtro elimina banda sintonizable. En segundo lugar, se han utilizado diferentes configuraciones basadas en anillos de silicio con dimensiones micrométricas para el desarrollo e implementación de diferentes procesadores de señal, tales como filtros reconfigurables y sintonizables y retardadores multicanal. Concretamente, se ha introducido un nuevo concepto inspirado en la técnica conocida como SCT, cuyo beneficio redunda en un aumento considerable del ancho de banda útil de las señales de radiofrecuencia a procesar gracias a / Lloret Soler, JA. (2012). Slow Light Effects in Photonic Integrated Circuits with Application to Microwave Photonics [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/16472 / Palancia
157

Gender Differences in the Language Development of Late-talking Toddlers at Age 3

Johnson, Nancy Ann 07 June 1996 (has links)
Language is a major part of a child's early developmental growth. Research examining early language shows a wide variation in the rate of language acquisition and its pattern of development. These variations also exist when language development is delayed. The purpose of this study was to investigate the possibility of a relationship between gender and language delay by looking for significant differences in the language skills of 3-year-old boys and girls who were identified as late-talkers (LTs) at the age of 2. Data used for analysis in this study were retrieved from data collected earlier as part of the Portland Language Development Project (PLDP) and a concurring study of late-talking girls. Subjects for this study were drawn from these larger cohorts. The files of all prospective subjects were examined for an expressive vocabulary of less than 50 words at 20-34 months, and for participation in the follow-up evaluation at age 3. Final selection of subjects for this study included 23 boys and 16 girls. Scores from five previously administered assessment measures were compiled for analysis, including the Developmental Sentence Score (DSS), the Expressive OneWord Picture Vocabulary Test (EOWPVT), the Goldman-Fristoe Test of Articulation (GFTA), the Test of Auditory Comprehension of Language-Revised {TACL-R), and the Peabody Picture Vocabulary Test-Revised. These measures were administered as part of the PLOP and the study of late-talking girls. Mean scores for the boys and the girls were computed for each assessment measure. A two-tailed t-test was used to analyze the differences between these mean scores. The results revealed a significant difference, beyond the .05 level of confidence, between the boys' and girls' scores for the EOWPVT. Although no other significant differences were found, it was noted that the boys' scores were consistently higher than the girls' scores on all measures. It was also noted that, on 4 out of 5 assessment measures, a higher percentage of girls did not respond or could not complete the test due to inability to attend. The fifth measure, the PPVT-R, was completed by all subjects.
158

Play in the Woods: The Role of the Dramaturg in Facilitating a Holistic, Slow Theater-Making Process

Nolan, Claudia 25 October 2018 (has links)
In this thesis, I document the ideas behind and my process for Play in the Woods, an experiment in slow theater-making that serves as a model for how dramaturgs can facilitate sustainable, holistic methods of performance. This model is grounded in feminist theater practices and the aesthetic of poor theater. In creating the performance of Play in the Woods, I as dramaturg invited participants to serve as co-creators, individually crafting pieces that examined fairytales and the role those stories have played on their lives. The performance was held out of doors at the Amethyst Brook Conservation Area on the afternoon of May 5th, 2018. This framework allowed for an examination of the role of childhood and memory, as well as space, place, and the natural world, on my and the other performers’ sense of self in light of our personal and cultural influences.
159

Detekce slow-rate DDoS útoků / Detection of slow-rate DDoS attacks

Sikora, Marek January 2017 (has links)
This diploma thesis is focused on the detection and protection against Slow DoS and DDoS attacks using computer network traffic analysis. The reader is introduced to the basic issues of this specific category of sophisticated attacks, and the characteristics of several specific attacks are clarified. There is also a set of methods for detecting and protecting against these attacks. The proposed methods are used to implement custom intrusion prevention system that is deployed on the border filtering server of computer network in order to protect Web servers against attacks from the Internet. Then created system is tested in the laboratory network. Presented results of the testing show that the system is able to detect attacks Slow GET, Slow POST, Slow Read and Apache Range Header and then protect Web servers from affecting provided services.
160

A study and analysis of selected factors contributing to retardation among fifth grade pupils in Sebring elementary schools with recommendation for programs of action

Unknown Date (has links)
"The purpose of this study is to make an analysis of the 1951-52 of class of fifth grade pupils to: 1. Find the cases of retardation. 2. Discover through study and research the underlying causes of the retardation. 3. Develop a keener understanding of retarded children. 4. Determine ways of working with these children more effectively"--Introduction. / Typescript. / "August, 1952." / "Submitted to the Graduate Council of Florida State University in partial fulfillment of the requirements for the degree of Master of Science." / Advisor: Virgil E. Strickland, Professor Directing Paper. / Includes bibliographical references (leaves 72-75).

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