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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.
111

Structure of the M31 satellite system : bayesian distances from the tip of the red giant branch

Conn, Anthony Rhys 07 February 2013 (has links) (PDF)
This study focuses on the spatial distribution of the M31 satellite system. A new Bayesian technique for determining object distances from the Tip of their Red Giant Branch is developed and used to obtain distance probability distributions for M31and 27 of its satellite galaxies. These distances are then used to calculate the satellite positions in three dimensions. Subsequent analysis of the resulting spatial distribution reveals striking inhomogeneity, with roughly half of the satellites confined to a curiously oriented thin disk. The distribution is also markedly asymmetric, with the majority of satellites lying on the Milky Way side of M31.
112

International entry modes in Brazil and the CAGE distances effects

Degano, Riccardo 25 February 2016 (has links)
Submitted by Riccardo Degano (riccardo.degano@gmail.com) on 2016-03-09T21:48:53Z No. of bitstreams: 1 29022016_MasterThesis_BR_Final.pdf: 1047509 bytes, checksum: 29eeca11947106b1b1086a9b6f746e23 (MD5) / Approved for entry into archive by Ana Luiza Holme (ana.holme@fgv.br) on 2016-03-10T12:19:57Z (GMT) No. of bitstreams: 1 29022016_MasterThesis_BR_Final.pdf: 1047509 bytes, checksum: 29eeca11947106b1b1086a9b6f746e23 (MD5) / Made available in DSpace on 2016-03-10T12:39:17Z (GMT). No. of bitstreams: 1 29022016_MasterThesis_BR_Final.pdf: 1047509 bytes, checksum: 29eeca11947106b1b1086a9b6f746e23 (MD5) Previous issue date: 2016-02-25 / The international entry mode choices have a relevant importance for the impact they have on successful internationalization strategies. Many theories have been developed to describe which entry mode may be better than another according to the particular situation. The CAGE Distances Framework developed by Ghemawat to identify which dimensions companies should look when develop an internationalization strategy, may be useful to identify also how those dimensions impact on the international entry mode decision. The aim of this thesis is to study which kind of relationship exists between Cultural, Administrative, Geographic and Economic Distances and international entry mode choice. It analyzes a sample of companies that have been entered in Brazil through a logistic regression. According to this analysis, a negative and significant relation between Cultural Distance and need of control exists, a positive one exists between Administrative and Geographic, while no significant relationship has been found with the Economic dimension. Those findings are conceivably explainable through the theories found by scholars, but a deeper analysis that may take into account the specificity of every country is highly recommended, like the one developed with Brazil in this thesis. / As opções internacionais de modo de entrada tem siginificativa importância no que diz respeito ao sucesso de estratégias de internacionalização. Diversos modelos teóricos têm sido desenvolvidos para descrever de que maneira um modo de entrada pode ser do que outro de acordo com uma situação específica. O teoria das distâncias CAGE, desenvolvido por Ghemawat visando a identificação de quais dimensões as empresas devem explorar quando desenvolvem uma estratégia de internacionalização, pode também ser útil para identificar como tais dimensões impactam sobre as decisões de modo de entrada em um contexto internacional. O objetivo desta tese é estudar que tipo de relação existente entre Distâncias Cultural, Administrativa, Geográfica e Econômica e a decisão do modo de entrada. Analisa uma amostra de empresas estrangeiras atuantes no mercado Brasileiro por meio de uma regressão logística. De acordo com esta análise, existe uma relação negativa e significativa entre Distância Cultural e necessidade de controle, uma relação positiva entre a Distância Administrativa e Geográfica, enquanto nenhuma relação significativa foi encontrada com a dimensão econômica. Essas descobertas já foram conceitualmente antecipadas por proposições teóricas previamente propostas em outros estudos, mas deve ser considerado que uma análise mais profunda focando especificidades de cada país seria altamente recomendada, tal como o desenvolvido com o Brasil nesta dissertação.
113

Perception des distances : effets des contraintes environnementales et des variations de la fluence métacognitive / Distance perception : the effects of the environmental constraints and of the variations of metacognitive fluency

Josa, Roman 15 December 2017 (has links)
La perception visuelle de l’espace est largement déterminée par les capacités visuelles des individus. Cependant, la recherche sur l’influence de variables dites non visuelles semble indiquer une importance déterminante des dimensions corporelle et émotionnelle sur la perception visuelle. Dans cette thèse, nous nous sommes intéressés à la perception des distances et avons tenté de comprendre en quoi nos perceptions pouvaient refléter la nature de nos interactions sensorimotrices avec notre environnement. Dans une première étude nous avons montré que des contraintes d’actions, tel que le coût énergétique, générées par les dispositions de l’environnement, pouvaient avoir une influence sur la perception de distances allocentriques. Dans une seconde étude, nous avons tenté de mettre en évidence le rôle du processus d’intégration sensorimotrice dans des tâches d’évaluation de distances, ainsi que de comprendre l’influence des modalités non visuelles, telles que l’audition et la motricité, dans ce même type de tâche. Enfin, dans une troisième étude, nous nous sommes intéressés au concept de fluence – i.e., information métacognitive renseignant le système sur la qualité de ses interactions dans son environnement – et proposons l’idée selon laquelle ce signal contenu dans le flux perceptif permettrait d’expliquer différentes variations perceptives liées aux contraintes de nos actions. Finalement, cette thèse défend une approche unifiée de la perception, selon laquelle la limite entre les concepts d’action et de perception devrait être repensée afin de rendre compte de la nature sensorimotrice de nos connaissances. / Visual perception of space is mainly known as depending upon one’s vision capacity. However, research about the influence of non-visual variables seems to indicate that the body also plays an important role in visual perception. In this Ph.D. thesis, we support the idea that distance perception has to be studied as a function of the sensorimotor interactions between the individuals and their environment. In the first study, we showed that action constraints in the environment such as energetic cost could influence allocentric distance perception. In the second study, we focused on the role of the sensorimotor integration process in distance perception tasks, as well as the influence of non-visual variables such as audition and motor activity. In the third study, we investigated the phenomenology of perception, and more precisely in the relative fluency of motor activity. In other words, we focused here on the metacognitive feedback that emerges from the quality of the interactions with the environment. We highlighted that such a metacognitive signal could explain the influence of action constraints on distance perception. Finally, this work provides strong supports to the idea of an integrative approach of perception according to which the theoretical boundary between perception and action is questioned by the sensorimotor nature of our knowledge.
114

Posicionamento topográfico de alvos visualizados através de espelho plano, estimando a precisão / Topographic positioning of targets seen through plane mirror estimating the accuracy

Pinto, Suelem Farias 02 December 2013 (has links)
Made available in DSpace on 2015-03-26T13:28:33Z (GMT). No. of bitstreams: 1 texto completo.pdf: 1410214 bytes, checksum: d6e65f9be9408724d99530c1a0f7cd58 (MD5) Previous issue date: 2013-12-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / Even in current times, there is a need to develop a topographic survey technique for situations in which the target is not directly visualized from the total station position. With this purpose, q project of a mirror and softwares that allow estimate the coordinates, and its uncertainties, of targets visualized through the mirror was developed. For the work development, 3D virtual models of different scenarios were made, employing CAD, and softwares, in which estimations of topographic coordinates of the targets and its uncertainties were made, were developed. Concludes that measuring the coordinates of the fiducial marks with a precision of one millimeter, the uncertainties on the coordinates of the real targets are above the centimeter and that instead of employing fiducial marks recorded in the mirror, is better to add graduated circles that allow measure the angles of attitude. With a precision of five seconds in the angles and millimeter on the coordinates of the targets comes to the accuracy better than the centimeter on the coordinates of the real targets. / Mesmo com o atual avanço tecnológico, há necessidade de se desenvolver uma técnica de levantamentos topográficos para situações em que o alvo não seja diretamente visualizado de onde a estação total está posicionada. Com este intuito, foi desenvolvido um projeto de um espelho e software que permitam estimar as coordenadas, e suas incertezas, de alvos visualizados indiretamente. Para a realização do trabalho foram construídas maquetes virtuais em 3D, empregando um CAD, de diversos cenários e foi elaborado software para estimar as coordenadas de marcas fiduciais no espelho, relacionar os sistemas do espelho e da estação total e por fim, estimar as coordenadas topográficas dos alvos e suas incertezas. Concluiu-se que medindo as coordenadas das marcas fiduciais com precisão de um milímetro, para uma mesma posição do espelho, da estação e dos alvos virtuais, as incertezas nas coordenadas dos alvos reais ficam acima do centímetro e que em vez de se empregar marcas fiduciais gravadas no espelho, é melhor adicionar círculos graduados que permitam medir os ângulos de atitude. Com precisão de cinco segundos nos ângulos e milímetro nas coordenadas dos alvos virtuais chega-se a precisão melhor que o centímetro nas coordenadas dos alvos reais.
115

Análise das emissões veiculares em trajetos urbanos curtos com localização por GPS / Vehicle emission analysis in urban short distances with GPS localization

Anderson Manzoli 27 March 2009 (has links)
Estuda-se o problema da emissão de gases por veículos automotores movidos a gasolina em trajetos curtos ercorridos em cidades pequenas e médias. Nessa situação, o tipo de percurso que ocorre com mais frequência é curto, o que significa circulação de veículos com os motores ainda frios. Sabe-se que esta circunstância constitui a condição menos favorável no que se refere à emissão de gases poluentes. Tecnologias recentes, como GPS e analisadores de gases portáteis, foram usados para se obterem dados fundamentais para o trabalho, como velocidade, tempo, coordenada espacial, aceleração, mensuração da emissão dos poluentes pelo escapamento do veículo e temperatura do motor. Os testes foram feitos com o motor frio e quente para que fosse possível descrever o comportamento da emissão dos gases nas duas condições. Determinou-se experimentalmente a emissão de CO e HC em diversas condições e construiu-se um banco de dados sobre como esses parâmetros interferem na geração desses gases nos percursos estabelecidos, fornecendo uma previsão mais realista. Os resultados pretendem conscientizar os administradores públicos acerca da necessidade de se mensurar a real emissão de poluentes em qualquer cidade, pois o número reduzido de automóveis não significa diretamente a inexistência de problemas com a poluição. Especialmente no caso das cidades pequenas e médias, esse resultado pode subsidiar uma política preventiva, para que não se alcancem os níveis catastróficos que hoje são encontrados nas grandes cidades. / This work studies the problem of gas emission by automotive petrol moved vehicles in short distances travelled in small and medium towns. In this situation, most distances are short. It means that vehicle circulates commonly with still cold engine, what is known to be the least favorable condition concerned to pollutant gas emission. Recent technologies like GPS and portable gas analyzers were used to obtain fundamental data, like speed, time, spacial coordinate, acceleration, pollutant emission by vehicle leakage and engine temperature. The tests were made with cold and hot engine, so that it would be possible to describe the gas emission behavior in both conditions. CO and HC emission were determined experimentally in several conditions and a data base was built after how these parameters interfere in the gas emission in the established routes, providing a more realistic view. These data can help public administrators to think about the need to measure the real pollutants emission in any town, because the reduced number of automobiles isn\'t directly related to the inexistence of pollution problems. Specially related to short and medium towns, this result may supply preventive politics, so that the catastrophic levels found in big cities nowadays won\'t be held.
116

Calibration of AGN Reverberation Distance Measurements

Koshida, Shintaro, Yoshii, Yuzuru, Kobayashi, Yukiyasu, Minezaki, Takeo, Enya, Keigo, Suganuma, Masahiro, Tomita, Hiroyuki, Aoki, Tsutomu, Peterson, Bruce A. 14 June 2017 (has links)
In Yoshii et al., we described a new method for measuring extragalactic distances based on dust reverberation in active galactic nuclei (AGNs), and we validated our new method with Cepheid variable stars. In this Letter, we validate our new method with Type Ia supernovae (SNe Ia) that occurred in two of the AGN host galaxies during our AGN monitoring program: SN 2004bd in NGC 3786 and SN 2008ec in NGC 7469. Their multicolor light curves were observed and analyzed using two widely accepted methods for measuring SN distances, and the distance moduli derived are m= 33.47 +/- 0.15 for SN 2004bd and 33.83 +/- 0.07 for SN 2008ec. These results are used to obtain independently the distance measurement calibration factor, g. The g value obtained from the SN Ia discussed in this Letter is gSN= 10.61 +/- 0.50, which matches, within the range of 1s uncertainty, gDUST = 10.60, previously calculated ab initio in Yoshii et al. Having validated our new method for measuring extragalactic distances, we use our new method to calibrate reverberation distances derived from variations of Ha emission in the AGN broad-line region, extending the Hubble diagram to z approximate to 0.3 where distinguishing between cosmologies is becoming possible.
117

Quantificando as inomogeneidades da matéria com Supernovas e Gamma-Ray Bursts / Quantifying the Matter Inhomogeneities with Supernovae and Gamma-Ray Bursts

Vinicius Consolini Busti 12 March 2009 (has links)
Nesta dissertação estudamos como os efeitos das inomogeneidades da matéria (escura e bariônica) modificam as distâncias e afetam a determinação dos parâmetros cosmológicos. As inomogeneidades são fenomenologicamente descritas pelo parâmetro de aglomeramento alpha e quantificadas pela equação da distância proposta por ZeldovichKantowskiDyer Roeder (ZKDR). Além disso, utilizando amostras de Supernovas e Gamma-Ray Bursts, aplicamos um teste chi quadrado para vincular os parâmetros de dois modelos cosmológicos distintos, a saber: o modelo LambdaCDM plano e o modelo com criação de matéria escura fria. Para o modelo LambdaCDM plano, vinculamos os parâmetros alpha e ­OmegaM considerando um prior gaussiano para a constante de Hubble. Realizamos também uma análise detalhada envolvendo duas calibrações distintas associadas aos dados de Gamma-Ray Bursts: uma calibração para o modelo LambdaCDM plano e outra para o modelo cardassiano. Verificamos que os resultados são fracamente dependentes da calibração adotada. Uma análise conjunta envolvendo Supernovas e Gamma-Ray Bursts permitiu quebrar a degenerescência entre o parâmetro de aglomeramento alpha e o parâmetro de densidade da matéria ­OmegaM. Considerando a calibração dos Gamma-Ray Bursts para o modelo LambdaCDM plano, o melhor ajuste obtido foi alpha = 1.0 e ­OmegaM = 0.30, com os parâmetros restritos ao intervalos 0.78 < alpha < · 1.0 e 0.26 < ­OmegaM < 0.36 (2sigma). Para o modelo com criação de matéria escura consideramos também um prior gaussiano para a constante de Hubble e as amostras de Supernovas e Gamma-Ray Bursts (calibrados para o modelo LambdaCDM plano). A degenerescência entre o parâmetro alpha e o parâmetro de criação gamma foi novamente quebrada através de uma análise conjunta das 2 amostras de dados. Para o melhor ajuste obtivemos alpha = 1.0 e gamma = 0.61, com os parâmetros restritos aos intervalos 0.85 < alpha < 1.0 e 0.56 < gamma < 0.66 (2sigma). / In this dissertation we study how the effects of matter (baryonic and dark) inhomogeneities modify the distances thereby affecting the determination of cosmological parameters. The inhomogeneities are phenomenologically described by the clumpiness parameter alpha and quantified through the equation distance proposed by ZeldovichKantowskiDyer Roeder (ZKDR). Further, by using Supernovae and Gamma-Ray Bursts separately, a chi-squared analysis was performed to constrain the parameter space for two distinct cosmological models, namely: the flat LambdaCDM model and the cold dark matter creation model. For the flat LambdaCDM model we have constrained the parameters alpha and ­OmegaM by considering a Gaussian prior for the Hubble parameter. A detailed analysis was also performed involving two different calibrations associated to the Gamma-Ray Bursts data: a calibration for the flat LambdaCDM model as well as for the cardassian model. We have verified that the results are weakly dependent on the adopted calibration. A joint analysis involving Supernovae and Gamma-Ray Bursts allowed us to break the degenerescence between the clumpiness parameter alpha and the matter density parameter ­OmegaM. By considering the calibration for the flat LambdaCDM model, the best fits obtained were equal to alpha = 1.0 and ­OmegaM = 0.30 with the parameters restricted on the intervals 0.78 < alpha < 1.0 and 0.26 < ­OmegaM < 0.36 (2sigma). For the dark matter creation model we have also adopted a Gaussian prior for the Hubble constant and the Supernovae and Gamma-Ray Bursts (calibrated for the flat LambdaCDM model) samples. The degenerescence between the clumpiness parameter alpha and the creation parameter gamma was again broken trough a joint analysis of the two data sample. For the best fits we have obtained alpha = 1.0 and gamma = 0.61 with the parameters restricted on the intervals 0.85 < alpha < 1.0 and 0.56 < gamma < 0.66 (2sigma).
118

Méthodes d'éclatement basées sur les distances de Bregman pour les inclusions monotones composites et l'optimisation / Splitting methods based on Bregman distances for composite monotone inclusions and optimization

Nguyen, Van Quang 17 July 2015 (has links)
Le but de cette thèse est d'élaborer des méthodes d'éclatement basées sur les distances de Bregman pour la résolution d'inclusions monotones composites dans les espaces de Banach réels réflexifs. Ces résultats nous permettent d'étendre de nombreuses techniques, jusqu'alors limitées aux espaces hilbertiens. De plus, même dans le cadre restreint d'espaces euclidiens, ils donnent lieu à de nouvelles méthodes de décomposition qui peuvent s'avérer plus avantageuses numériquement que les méthodes classiques basées sur la distance euclidienne. Des applications numériques en traitement de l'image sont proposées. / The goal of this thesis is to design splitting methods based on Bregman distances for solving composite monotone inclusions in reflexive real Banach spaces. These results allow us to extend many techniques that were so far limited to Hilbert spaces. Furthermore, even when restricted to Euclidean spaces, they provide new splitting methods that may be more avantageous numerically than the classical methods based on the Euclidean distance. Numerical applications in image processing are proposed.
119

Untersuchungen zur Entfernungsmessung terrestrischer Long-Range Laserscanner

Martienßen, Thomas, Geier, Andreas, Wand, Robert January 2016 (has links)
Der vorliegende Beitrag beschäftigt sich mit Untersuchungen zur Entfernungsmessung terrestrischer Long-Range Laserscanner. Für diese Studie wurden dem Institut für Markscheidewesen und Geodäsie dankenswerter Weise von der Firma RIEGL ein Laserscanner VZ-4000 zur Verfügung gestellt. In diesem Beitrag werden der Versuchsaufbau erläutert und erste Ergebnisse des Soll-Ist-Vergleiches gezeigt. Die unterschiedlichen Einflussgrößen, wie Temperatur und Luftdruck, die bei Messungen auf große Entfernungen eine Rolle spielen, werden angesprochen. / This paper deals with actual researches for measuring distances of terrestrial long-range Laser scanners. The Institute for Mine Surveying and Geodesy had a laser scanner VZ-4000 by the company RIEGL easy and unconventional provided. The paper presents the experimental setup and the results of the target-actual comparison. Several influences, for example temperature and atmospheric pressure, are considered for long-range measurements.
120

Upplevda och faktiska avstånd för fotgängare : En flerfallsstudie av stationsnära lägen

Haddleton, Vendela, Henriksson, Lisa January 2020 (has links)
Inom stadsplanering finns idag ett stort fokus på skapandet av gångvänliga städer med godtagbara gångavstånd. En gångvänlig miljö kan förkorta både det upplevda och det faktiska avståndet. Begränsningar i vad som finns tillgängligt inom ett accepterbart gångavstånd kan leda till att många väljer att åka bil framför att transportera sig till fots. Kollektivtrafik kan utöka räckvidden för fotgängare, vilket kräver att även promenader till och från stationer är, och upplevs, kortare. Gävle kommun planerar en ny tågstation som kommer att innebära en ökad tillgänglighet till kollektivtrafik för många människor, och således ett ökat användande av hållbara transporter. Studiens syfte har varit att undersöka hur miljöns utformning påverkar upplevda och faktiska avstånd för fotgängare. Målet var att skapa underlag för hur stationsnära miljöer kan utformas för att främja gångtrafik, med förhoppningen att fler ska vilja promenera till och från närliggande målpunkter anslutna till Gävles nya station. De teorier som utvecklats i studien appliceras på verkligheten genom att ett förslag för den nya stationen presenteras. Eftersom Gävle kommun befinner sig tidigt i planeringsprocessen gjordes en flerfallsstudie för att studera liknande områden som kan generaliseras till tågstationen. En dokumentstudie utfördes för att ta reda på vad sakkunniga framhåller som viktigt vid planering av tågstationer samt hur andra kommuner planerar för att uppnå gångvänliga stationsmiljöer. För att undersöka hur fotgängare rör sig i stationsnära miljöer utfördes observationer och inventeringar av befintliga stråk. Stråk kring planområdet för tågstationen undersöktes för att erhålla kunskap om området, vilket låg till grund för att kunna ge lämpliga förslag på framtida utformning. Studien resulterade i fyra aspekter som alla behövs för att skapa gångvänliga miljöer i stationsnära lägen. Studien har dessutom visat vikten av att gångvänliga miljöer planeras utifrån fotgängarens perspektiv, vilket kräver att miljön som planeras upplevs med en fotgängares ögon. / Urban planning today emphasizes the creation of walkable cities with acceptable walking distances. A walkable environment can shorten both the perceived and the actual distance. Limitations in what is available within acceptable walking distance result in people choosing to go by car rather than walking. Public transport can complete the trip, which requires that both perceived and actual distances to and from stations are shorter. Gävle municipality is planning a new train station, which will give many people increased access to public transport and thus potentially increase the use of sustainable transportation. The aim of the study has been to investigate how the design of the environment affects pedestrians perceived and actual distances. The objective was to create a basis for how station environments can be designed to promote pedestrian traffic, hoping that more people would be willing to walk to access Gävle’s new station. The theories developed in the study are applied to reality by presenting a proposal for the new station. A multiple case study was conducted to study similar areas that can be generalized to the new train station, since the municipality is in the planning phase. What experts emphasize as important when planning train stations and how other municipalities plan to achieve walkable train station environments was reviewed in useful documents. In order to investigate how pedestrians walk within the area around train stations, observations and inventories of existing footpaths were carried out. Paths around the plan area of the train station were explored to obtain knowledge about the area, which made up a basis in order to give suitable suggestions for future design. The study resulted in four aspects that are all required when creating walkable environments around stations. The study has also shown the importance of the pedestrian perspective when planning walkable environments, which requires that the planning area is experienced through the eyes of a pedestrian.

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