• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 166
  • 62
  • 30
  • 14
  • 10
  • 10
  • 5
  • 4
  • 4
  • 2
  • 2
  • 2
  • 2
  • 1
  • 1
  • Tagged with
  • 383
  • 102
  • 73
  • 56
  • 53
  • 45
  • 45
  • 42
  • 42
  • 38
  • 35
  • 34
  • 34
  • 29
  • 27
  • 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.
91

Multilingual Zero-Shot and Few-Shot Causality Detection

Reimann, Sebastian Michael January 2021 (has links)
Relations that hold between causes and their effects are fundamental for a wide range of different sectors. Automatically finding sentences that express such relations may for example be of great interest for the economy or political institutions. However, for many languages other than English, a lack of training resources for this task needs to be dealt with. In recent years, large, pretrained transformer-based model architectures have proven to be very effective for tasks involving cross-lingual transfer such as cross-lingual language inference, as well as multilingual named entity recognition, POS-tagging and dependency parsing, which may hint at similar potentials for causality detection. In this thesis, we define causality detection as a binary labelling problem and use cross-lingual transfer to alleviate data scarcity for German and Swedish by using three different classifiers that make either use of multilingual sentence embeddings obtained from a pretrained encoder or pretrained multilingual language models. The source languages in most of our experiments will be English, for Swedish we however also use a small German training set and a combination of English and German training data.  We try out zero-shot transfer as well as making use of limited amounts of target language data either as a development set or as additional training data in a few-shot setting. In the latter scenario, we explore the impact of varying sizes of training data. Moreover, the problem of data scarcity in our situation also makes it necessary to work with data from different annotation projects. We also explore how much this would impact our result. For German as a target language, our results in a zero-shot scenario expectedly fall short in comparison with monolingual experiments, but F1-macro scores between 60 and 65 in cases where annotation did not differ drastically still signal that it was possible to transfer at least some knowledge. When introducing only small amounts of target language data, already notable improvements were observed and with the full German training data of about 3,000 sentences combined with the most suitable English data set, the performance for German in some scenarios even almost matches the state of the art for monolingual experiments on English. The best zero-shot performance on the Swedish data was even outperforming the scores achieved for German. However, due to problems with the additional Swedish training data, we were not able to improve upon the zero-shot performance in a few-shot setting in a similar manner as it was the case for German.
92

ANALYSES OF URSEIS MOHO REFLECTIONS BENEATH THE PREURALIAN FOREDEEP OF THE URAL MOUNTAINS, RUSSIA

Atef, Ali Hadi, Mr 13 September 2007 (has links)
No description available.
93

Estimating the Relative Value of Individual Strokes Gained on the PGA Tour

Censullo, Alex 01 January 2017 (has links)
This study compares the predictive ability of newly introduced strokes gained measures on PGA Tour earnings performance with that of more conventional golf statistics. It is found that the strokes gained measures explain slightly more of the variability in the distribution of earnings. Strokes gained on the approach shot are determined to be the most valuable relative to the other strokes gained metrics.
94

Optimisation of shot peening for 12Cr steel in steam turbine blade applications

Newby, Mark January 2013 (has links)
Power generation in thermal stations typically relies on large steam turbines. The corrosion resistant steel blades used in the last stage of a typical low pressure rotor set are approximately 1m long and experience high centrifugal loading during service. They operate in a wet steam environment, at approximately 60°C while rotating at 3000rpm, and failure modes include high and low cycle fatigue, stress corrosion cracking or corrosion fatigue. The blades are retained by a fir tree root which is normally shot-peened to generate compressive residual stresses that resist crack initiation. Finite element (FE) modelling has indicated that, in the absence of shot-peening, stresses above yield are induced at the fir tree root during operation. In a shot-peened blade these lead to relaxation of the shot peening residual stresses. To date, no systematic information has been obtained on the level of residual stresses induced in the fir tree by shot-peening and their subsequent relaxation during service loading, nor are there any guidelines as to the magnitude of residual stresses necessary to ensure integrity of the turbine over a life span of at least twenty years. At least one of these blades has suffered catastrophic failure in recent years causing severe damage, in excess of €100M, to the turbine-generator set on a South African power station [1]. This thesis reports results from a comprehensive program of residual stress measurements at the shot-peened fir tree roots of service blades, and in specimens that simulate the root conditions, using diffraction data from laboratory and synchrotron X-ray radiation (SXRD). Shot-peening coverage between 75% and 200% was used and stresses were measured over a depth of 5mm into the blades/specimens. Measurements were made in the as-peened condition and after applying cyclic stresses representative of overspeed proof testing and of service operation. The results were used to calibrate FE modelling of residual stresses and as input into fatigue life prediction.
95

Zero-shot Learning for Visual Recognition Problems

Naha, Shujon January 2016 (has links)
In this thesis we discuss different aspects of zero-shot learning and propose solutions for three challenging visual recognition problems: 1) unknown object recognition from images 2) novel action recognition from videos and 3) unseen object segmentation. In all of these three problems, we have two different sets of classes, the “known classes”, which are used in the training phase and the “unknown classes” for which there is no training instance. Our proposed approach exploits the available semantic relationships between known and unknown object classes and use them to transfer the appearance models from known object classes to unknown object classes to recognize unknown objects. We also propose an approach to recognize novel actions from videos by learning a joint model that links videos and text. Finally, we present a ranking based approach for zero-shot object segmentation. We represent each unknown object class as a semantic ranking of all the known classes and use this semantic relationship to extend the segmentation model of known classes to segment unknown class objects. / October 2016
96

The Effects of Needle Play on Pre-School Children's Anxiety Concerning Injections

Belyea, Michelle Anne 01 January 1985 (has links)
The purpose of this study was to determine the effects of needle play in reducing pre-school children's anxiety concerning injections. The Pre-school Observational Scale of Anxiety was used to measure the degree of anxiety experienced by the children. The hypothesis stated that there would be a significant decrease in anxiety of pre-school children who participated in needle play as compared with the anxiety scores of pre-school children who did not participate in needle play.The sample consisted of 20 pre-school children who were receiving routine health care and injections for immunizations or PPDs (purified protein derivative) at a county health department in the southeast. After obtaining informed consent, children were randomly assigned to either a control group (n = 10) or experimental group (n = 10). The control group was involved in putting together a puzzle with the investigator prior to their injection. The experimental group participated in needle play with the investigator prior to their injection. The Pre-school Observational Scale of Anxiety (POSA) which specifies behavioral indicators of anxiety in children was used on all subjects immediately prior to the actual needle penetration and a score was given to each subject.The scores on the Pre-school Observational Scale of Anxiety showed no statistically significant difference between the control group and the experimental group when analyzed using the Mann-Whitney U Test. On the basis of these findings, the hypothesis that pre-school children who participate in needle play immediately prior to receiving an injection would show a significant decrease in anxiety when compared to pre-school children who did not-participate in needle play prior to an injection was not accepted.
97

Trénink a výkonnost vrhačky. / Training and performance of a shot put thrower.

Radová, Pavlína January 2013 (has links)
Title Training and performance of a shot put thrower Aim of study The aim of study was to analyze performance development of shot put thrower Pavlína Radová in a five-year period. Analysis was focused on connection between the dynamics of athletic performance and the effect of training load during each of the two training cycles 2010/2011 and 2011/2012. Methods In this thesis, we used auto-analysis and comparison. Data for analysis of training load and performance development were obtained from the training diaries of the years 2010/2011 and 2011/2012. Results Sports performance development was majorly affected by character of training load and mental condition of the athlete in each yearly training cycle. Poorly chosen training load and insufficient regeneration lead to stagnation or decline in physical performance. Individual approach of the coach and his communication with trainee is very important. Key words Sports training, shot put, performance, analysis, training load
98

The Good Killing

Aaron, Alex F 20 December 2013 (has links)
This paper will provide a far-ranging analysis of the relevant aspects of the filmmaking process as it pertains to the development and production of the thesis project, The Good Killing. This analysis will include both a detailed, biographic overview of the making of the film, as well as an in-depth critique of the creative decision-making and practical methodology that guided the production. In this regard, special attention will be first be given to how the project was initially conceived, and, broadly speaking, what was originally intended. Secondly, proceeding sections will examine key elements of the filmmaker’s technical planning, performance, and working philosophy, specifically citing directing style, cinematography, sound and editing. Through this evaluative process, the film will be judged from the standpoint of both concept and execution in order to determine overall success.
99

Quantum Shot Noise in Graphene / Bruit de grenaille quantique dans le graphène

Mostovov, Andrey 23 April 2014 (has links)
Nous avons mené une étude expérimentale du bruit de grenaille quantique dans une mono-couche de graphène. La conductance et l'effet Hall quantique ont été également examinés. Le modèle théorique, décrivant la conductance et le bruit quantique dans du graphène idéal (balistique) a été proposé par Tworzydlo et al., 2006. Dans du graphène diffusif, plus facilement réalisable expérimentalement, le bruit de grenaille a été étudié numériquement par plusieurs auteurs (San-Jose et al., 2007, Lewenkopf et al., 2008, Logoteta et al., 2013). Les conclusions des premiers travaux expérimentaux (DiCarlo et al., 2008 and Danneau et al., 2008) sur ce sujet n'en ont pas permis une compréhension suffisamment approfondi et des études complémentaires sont nécessaires. Dans notre expérience nous avons tenté de réduire au maximum les contributions du système de mesure sur le signal détecté en effectuant une mesure du bruit en tension quatre points et en utilisant la détection en cross-corrélation. En plus, notre système de mesure inclut des amplificateurs bas bruit cryogéniques faits maison combinés avec des filtres passe-bande alors que notre couche de graphène contient une constriction au centre. n utilisant les résultats des mesures de la conductance et de l'effet Hall quantique nous avons déterminé le libre parcours moyen dans notre échantillon et conclu qu'il est dans le régime diffusif. Les valeurs du facteur de Fano que nous avons extraites sont en bon accord avec les simulations pour ce régime, un pic au point de Dirac prévu par Lewenkopf et al. a été observé. D'autre part, nos résultats sont compatibles avec ceux de Danneau et al. and DiCarlo et al. / We have conducted an experimental study of the quantum shot noise in a mono-layer graphene device. Conductance of the device and the quantum Hall effect were also investigated. A theoretical model, describing conductance and quantum shot noise in ideal (ballistic) graphene was proposed by Tworzydlo et al., 2006. In diffusive graphene, that is much easier achievable experimentally, shot noise was investigated numerically by several authors (San-Jose et al., 2007, Lewenkopf et al., 2008, Logoteta et al., 2013). Conclusions of the first experimental works (DiCarlo et al., 2008 and Danneau et al., 2008), addressing this problem, didn’t lead to an enough broad understanding of it and a further investigation was required. In our experiment we intended to maximally reduce the contributions of the measurement system to the detected signal by performing four-point voltage noise measurement as well as by using cross-correlation detection. In addition to that, our measurement system include home-made cryogenic low-noise amplifiers combined with band-pass filters, while our experimental device carries a constriction in the center of graphene layer and side-gates are used instead of back-gate. First, using the results of the conductance and of the quantum Hall effect measurements we determined the mean free path in our sample and concluded that it was in diffusive regime. The extracted values of the Fano factor show a good agreement with the above-mentioned simulations for this regime, in particular, the peak at Dirac point, predicted by Lewenkopf et al., was observed. Moreover our results are consistent with those of Danneau et al. and DiCarlo et al.
100

Efeito do jateamento com granalhas de aço na tensão residual e no comportamento mecânico da liga de alumínio 6082 / Effect of shot peening on residual stress and mechanical behavior of aluminum alloy 6082

Borges, Arnaldo Augusto Ciquielo 13 December 2017 (has links)
A liga de alumínio 6082 apresenta de média para alta resistência mecânica e é de grande importância no mercado de perfis extrudados. O processo de jateamento com granalha de aço em componentes automotivos e aeronáuticos, visando induzir uma condição otimizada de tensão residual de compressão na superfície, tem se mostrado eficaz na melhoria das propriedades mecânicas em fadiga desses componentes. Neste sentido, este trabalho tem como objetivo estudar os efeitos do jateamento com granalhas de aço na tensão residual e no comportamento mecânico em fadiga da liga de alumínio 6082 solubilizada e envelhecida artificialmente. Inicialmente foram feitos tratamentos térmicos de solubilização e envelhecimento artificial visando a determinação da melhor condição em termos de resistência mecânica da liga de alumínio 6082. A seguir foram realizados experimentos com diversos tipos de granalhas esféricas de aço e em condições variadas de jateamento (velocidade de rotação e tempo), definindo-se a melhor condição de tensão residual medida por difração de raios x. Ensaios de fadiga em corpos de prova jateados com granalha de aço na melhor condição de tensão residual foram executados em máquina flexo-rotativa e comparados com os resultados do material sem jateamento. A melhor condição de tensão residual ocorreu em decorrência do jateamento com o uso da granalha de aço S170PEE, rotação da turbina à 2500 rpm e tempo de exposição de 1 minuto. A curva de tensão residual em profundidade para a condição escolhida apresentou resultados coerentes somente até 76 μm devido à presença de grãos grandes em profundidades superiores a esta. As curvas S-N mostraram que houve um ganho na vida em fadiga em tensões elevadas e baixo número de ciclos para romper devido jateamento com granalha de aço. Ao contrário, ocorreu um efeito deletério na vida em fadiga em tensões baixas e número de ciclos elevados para romper, devido à influência do aumento da rugosidade em ensaios de fadiga mais longos. / Aluminum alloy 6082 exhibits medium to high strength and is widely used as extruded products. Shot peening of automobile and aircraft components, carried out to induce optimum residual compressive stress on the surface, improves fatigue properties of these components. In this context, the aim of this investigation was to study the effects of shot peening on the residual stress and fatigue behavior of solution treated and artificially aged 6082 aluminum alloy. Initially, solution treatment and artificial ageing of this alloy were carried out to determine the best conditions in terms of alloy strength. Subsequently, experiments were carried out with different types of spherical steel shots, under a variety of peening conditions (rotation speed and duration), to define the best set of conditions to increase residual stress that was measured using x-ray diffraction. Fatigue tests were carried out using a rotating-bending machine on shot peened specimens that had the highest residual stress. These results were compared with those of specimens that were not shot peened. The highest residual stress was observed when peening was done with S170PEE steel shots, at 2500 rpm for 1 minute. The variation in residual stress as a function of depth, for the above-mentioned peening conditions, was coherent only up to a depth of 76 μm and attributable to the presence of large grains at depths higher than this. The S-N curves revealed an increase in fatigue life at high stresses and at low cycles to failure and attributed to shot peening. Contrary to this, a deleterious effect in terms of reduction in fatigue life was observed at low stresses and at high cycles to failure, due to increase in surface roughness of the specimens during the extended fatigue tests.

Page generated in 0.0633 seconds