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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.
1

Affective Intelligence, The Political Persuasion Process, And Outcome Intent: An Experimental Test

Curran, Michael D. January 2008 (has links)
Political communication scholars aim to understand the effect of messages on political attitudes and behavior. Past scholarship has identified three sources of influence in forming attitudes and behavior: affective, cognitive, and personality factors. While much attention has been paid to the impact of each single factor, little research has attempted to integrate them. Using the Affective Intelligence model as a theoretical point of departure (Marcus, & MacKuen, 1993; Marcus et al., 2000), this dissertation explored the simultaneous--and, in some cases, interactive relationships--between these attitudinal and behavioral influences. An experiment was conducted to answer three questions: first, do the causal claims made by Marcus and colleagues regarding the impact of emotion on political attitudes and behavior hold-up outside the realm of survey research? Second, what role does cognitive appraisals of messages play in the political persuasion process? Finally, does political efficacy moderate the relationships between induced emotional response, cognitive appraisals of messages, and political attitudes and behavior? Alternatively stated, does political efficacy link these factors together?The results of this study should be carefully interpreted as the causal instrument underlying manipulated attitudes was not transparent. The desired experimental manipulation--induced anxiety--was not unidimensional. While inductions did induce negative affect, they simultaneously induced positive affect. Within the confines of this document, this result is discussed at length and numerous possible explanations are offered.Structural equation modeling indicated that affect had a small impact on political attitudes and behavior. Likewise, the impact of cognitive appraisals of messages on attitudes and behavior was small. Alternatively, internal efficacy had a substantial main effect--not an interactive effect--on political attitudes and behavior.In summary, the results demonstrated the power of personality in predicting political attitudes and behavior. By trait, some individuals are more politically efficacious than others. Those with higher levels of internal efficacy tended to identify experimental messages as relevant to the attitudes they held, indicating that confidence in one's ability to comprehend politics and understand political happenings leads to identifying message content as applicable or appropriate. Additionally, these same individuals were likely to seek out more information about politics.
2

Pulling the other one: 1st- and 2nd-order visual information interact to determine perceived location.

Whitaker, David J., McGraw, Paul V., Keeble, David R.T., Skillen, Jennifer January 2004 (has links)
No / We demonstrate that the 1st- and 2nd-order characteristics of a visual stimulus can have a profound influence on each other in terms of perceived position. We use the parameter of spatial separation to selectively manipulate the effect of one characteristic upon the other. 1st-order features have their largest effect upon the perceived position of 2nd-order structure when separation is small, whilst the reciprocal effect is maximal at large separations. Implications for models of 1st- and 2nd-order interaction are discussed.
3

The 2nd-Order Smooth Variable Structure Filter (2nd-SVSF) for State Estimation: Theory and Applications

Afshari, Hamedhossein 06 1900 (has links)
Kalman-type filtering methods are mostly designed based on exact knowledge of the system’s model with known parameters. In real applications, there may be considerable amount of uncertainties about the model structure, physical parameters, level of noise, and initial conditions. In order to overcome such difficulties, robust state estimation techniques are recommended. This PhD thesis presents a novel robust state estimation method that is referred to as the 2nd-order smooth variable structure filter (2nd-order SVSF) and satisfies the first and second order sliding conditions. It is an extension to the 1st-order SVSF introduced in 2007. In the 1st-order SVSF chattering is reduced by using a smoothing boundary layer; however, the 2nd-order SVSF alleviates chattering by preserving the second order sliding condition. It reduces the estimation error and its first difference until the existence boundary layer is reached. Then after, it guarantees that the estimation error and its difference remain bounded given bounded noise and modeling uncertainties. As such, the 2nd-order SVSF produces more accurate and smoother state estimates under highly uncertain conditions than the 1st-order version. The main issue with the 2nd-order SVSF is that it is not optimal in the mean square error sense. In order to overcome this issue, the dynamic 2nd-order SVSF is initially presented based on a dynamic sliding mode manifold. This manifold introduces a variable cut-off frequency coefficient that adjusts the filter bandwidth. An optimal derivation of the 2nd-order SVSF is then obtained by minimizing the state error covariance matrix with respect to the cut-off frequency matrix. An experimental setup of an electro-hydrostatic actuator is used to compare the performance of the 2nd-order SVSF and its optimal version with other estimation methods such as the Kalman filter and the 1st-order SVSF. Experiments confirm the superior performance of the 2nd-order SVSF given modeling uncertainties. / Thesis / Doctor of Philosophy (PhD)
4

二階非線性微分方程與應用 / Nonlinear differential equation of second order and its applications

陳仁發, Chen, Ren Fa Unknown Date (has links)
在這篇論文當中,我們引用`海岸綠堤--水筆仔'網站上的研究資料並且藉由Matlab程式軟體的幫助建構數學模型,我們討論以下的二階非線性微分方程 (i) u''(t)=f(u(t)), u(t_0)=u_0, u'(t_0)=u_1. (ii) u''(t)=f(u'(t)), u(t_0)=u_0, u'(t_0)=u_1. 我們比較拋物線函數,立方函數,傅立葉和函數,正弦和函數並且從這些函數中選出最好的一個當作我們的模型,我們得到一些主要的結果。 / In this paper, we use the real data from website of `Seacoast Green Bank--Kandelia' and construct mathematical models with the help of Matlab, we discuss the following nonlinear 2nd order differential equation (i) u''(t)=f(u(t)), u(t_0)=u_0, u'(t_0)=u_1. (ii) u''(t)=f(u'(t)), u(t_0)=u_0, u'(t_0)=u_1. We compared with the functions of parabolic, cubic, Fourier summation, sum of sine and choose the best one from them as our model, we have obtained main results.
5

Nicht-Nachhaltigkeit auf der Suche nach einer politischen Form. Konturen der demokratischen Postwachstumsgesellschaft. Abhandlung

Blühdorn, Ingolfur 06 1900 (has links) (PDF)
Der vorliegende Beitrag untersucht das Dreiecksverhältnis zwischen ökologischer Nachhaltigkeit, wirtschaftlichem Wachstum und liberaler Demokratie und stellt fest, dass dieses sich in den westlichen Konsumgesellschaften im Angesicht der zunehmenden lebensweltlichen Manifestation der "Grenzen des Wachstums" grundlegend neu konfiguriert. Dabei zeichnen sich tatsächlich die Konturen einer "demokratischen Postwachstumsgesellschaft" ab - allerdings unter gänzlich anderen Vorzeichen, als es der überwiegende Teil der Transformationsforschung ersehnt. In der Absicht, einen Beitrag zur Rückkopplung der normativen und sich als transformativ verstehenden Teile der Nachhaltigkeitsforschung an die sozialwissenschaftliche Analyse moderner Gesellschaften zu leisten, zeigt der Beitrag zunächst, wie im Bereich umweltpolitischer und demokratiebezogener Diskurse zentrale Narrative, die über Jahrzehnte die Debatte bestimmt haben, heute ihre Glaubwürdigkeit verlieren und sich damit das Feld für eine Neujustierung der Dreiecksbeziehung eröffnet. Anschließend wird aus gesellschaftstheoretischer Perspektive ausgeleuchtet, wie die Demokratie im Zeichen moderner Subjektivitätsverständnisse und bestenfalls noch moderater Wachstumsraten zunehmend zu einem Mittel der "nachhaltigen" Verteidigung nicht-nachhaltiger Lebensstile wird. Entschiedener denn je, so zeigt sich, erheben moderne Konsumgesellschaften die "Politik der Nicht-Nachhaltigkeit" zu ihrem Prinzip.
6

Estruturas de edifícios em concreto armado submetidas a ações verticais e horizontais / Reinforced concrete structures of buildings subjected to vertical and horizontal loads

Prado, José Fernão Miranda de Almeida 28 August 1995 (has links)
Nos últimos anos a presença da informática auxiliando os projetos de estruturas de edifícios em concreto armado com múltiplos pavimentos tem atingido grandes proporções. Particularmente em relação à análise das respostas da estrutura frente a solicitações impostas, essa presença possibilita a consideração de modelos estruturais teóricos muito consistentes. Por outro lado, tradicionalmente existem modelos chamados de simplificados que também retratam as respostas da estrutura, porém normalmente com menor grau de aproximação em relação ao comportamento real. Nesse sentido, são apresentadas modelagens de estruturas convencionais de edifícios compreendidas pelos dois aspectos citados, sendo analisados esforços solicitantes e deslocamentos em vigas e pilares frente a ações verticais e horizontais (análise elástico-linear). Notadamente, há uma grande preocupação com o estudo da evolução dos esforços solicitantes nesses elementos ao longo da altura do edifício. Também são abordados os esforços de 2ª ordem global, que aparecem quando atuam simultaneamente as ações verticais e horizontais. Com o intuito de exemplificar e comparar resultados, diferentes modelos estruturais são utilizados na análise do projeto de um edifício em concreto armado com múltiplos pavimentos, construído na cidade de São Carlos-SP, devendo-se destacar a modelagem tridimensional. / In the last years the computation presence auxiliaring the designs of reinforced concrete structures of multistorey buildings has reached great proportions. Particularly concerning the analysis of structural answers due to imputed solicitations, this presence makes possible the consideration of theoretical structural models very consistents. In the other side, traditionally there are models called simplifieds that also describe the structural answers, however normally with less approximation degree concerning the real behavior. In this way, modellings of conventional building structures comprehended by the two cited aspects are presented, being analysed efforts and displacements in beams and columns due to vertical and horizontal loads (elastic-linear analysis). Notably, there is a great preoccupation with the study of the efforts evolution in these elements along the building height. Also are discussed the global 2nd. arder efforts, that appear when the vertical and horizontal loads act simultaneously. In order to exemplify and to compare results, different structural models are utilized in the analysis of the design of a reinforced concrete multistorey building, constructed in São Carlos city, São Paulo state, having to detach the tridimensional modelling.
7

Estruturas de edifícios em concreto armado submetidas a ações verticais e horizontais / Reinforced concrete structures of buildings subjected to vertical and horizontal loads

José Fernão Miranda de Almeida Prado 28 August 1995 (has links)
Nos últimos anos a presença da informática auxiliando os projetos de estruturas de edifícios em concreto armado com múltiplos pavimentos tem atingido grandes proporções. Particularmente em relação à análise das respostas da estrutura frente a solicitações impostas, essa presença possibilita a consideração de modelos estruturais teóricos muito consistentes. Por outro lado, tradicionalmente existem modelos chamados de simplificados que também retratam as respostas da estrutura, porém normalmente com menor grau de aproximação em relação ao comportamento real. Nesse sentido, são apresentadas modelagens de estruturas convencionais de edifícios compreendidas pelos dois aspectos citados, sendo analisados esforços solicitantes e deslocamentos em vigas e pilares frente a ações verticais e horizontais (análise elástico-linear). Notadamente, há uma grande preocupação com o estudo da evolução dos esforços solicitantes nesses elementos ao longo da altura do edifício. Também são abordados os esforços de 2ª ordem global, que aparecem quando atuam simultaneamente as ações verticais e horizontais. Com o intuito de exemplificar e comparar resultados, diferentes modelos estruturais são utilizados na análise do projeto de um edifício em concreto armado com múltiplos pavimentos, construído na cidade de São Carlos-SP, devendo-se destacar a modelagem tridimensional. / In the last years the computation presence auxiliaring the designs of reinforced concrete structures of multistorey buildings has reached great proportions. Particularly concerning the analysis of structural answers due to imputed solicitations, this presence makes possible the consideration of theoretical structural models very consistents. In the other side, traditionally there are models called simplifieds that also describe the structural answers, however normally with less approximation degree concerning the real behavior. In this way, modellings of conventional building structures comprehended by the two cited aspects are presented, being analysed efforts and displacements in beams and columns due to vertical and horizontal loads (elastic-linear analysis). Notably, there is a great preoccupation with the study of the efforts evolution in these elements along the building height. Also are discussed the global 2nd. arder efforts, that appear when the vertical and horizontal loads act simultaneously. In order to exemplify and to compare results, different structural models are utilized in the analysis of the design of a reinforced concrete multistorey building, constructed in São Carlos city, São Paulo state, having to detach the tridimensional modelling.
8

Modélisation du canal de propagation Terre-Espace en bandes Ka et Q/V : synthèse de séries temporelles, variabilité statistique et estimation de risque / Modelling of the Earth-Space propagation channel in Ka and Q/V bands : time series synthesis, statistical variability and risk estimation

Boulanger, Xavier 15 March 2013 (has links)
Les bandes de fréquences utilisées conventionnellement pour les systèmes fixes de télécommunication par satellites (bandes C et Ku i.e. 4-15 GHz) sont congestionnées. Néanmoins, le marché des télécommunications civil et de défense accuse une demande de plus en plus importante en services multimédia haut-débit. Par conséquent, l'augmentation de la fréquence porteuse vers les bandes Ka et Q/V (20-40/50 GHz)est activement étudiée. Pour des fréquences supérieures à 5 GHz, la propagation des signaux radioélectriques souffre de l'atténuation troposphérique. Parmi les différents contributeurs à l'affaiblissement troposphérique total(atténuation, scintillation, dépolarisation, température de bruit du ciel), les précipitations jouent un rôle prépondérant. Pour compenser la détérioration des conditions de propagation, des techniques de compensation des affaiblissements (FMT: Fade Mitigation Technique) permettant d'adapter en temps réel les caractéristiques du système en fonction de l'état du canal de propagation doivent être employées. Une alternative à l'utilisation de séries temporelles expérimentales peu nombreuses est la génération de séries temporelles synthétiques d'atténuation due à la pluie et d'atténuation totale représentatives d'une liaison donnée.Le manuscrit est organisé autour de cinq articles. La première contribution est dédiée à la modélisation temporelle de l'affaiblissement troposphérique total. Le deuxième article porte sur des améliorations significatives du modèle de génération de séries temporelles d'atténuation due à la pluie recommandé par l'UITR.Les trois contributions suivantes constituent une analyse critique et une modélisation de la variabilité des statistiques du 1er ordre utilisées lors des tests des modèles de canal. La variance de l'estimateur statistique des distributions cumulatives complémentaires de l'atténuation due à la pluie et de l'intensité de précipitation est alors mise en évidence. Un modèle à application mondiale paramétré au moyen de données expérimentales est proposé. Celui-ci permet, d'une part, d'estimer les intervalles de confiance associés aux mesures de propagation et d'autre part, de quantifier le risque en termes de disponibilité annuelle associée à la prédiction d'une marge de propagation donnée. Cette approche est étendue aux variabilités des statistiques jointes. Elle permet alors une évaluation statistique de l'impact des techniques de diversité de site sur les performances systèmes, tant à microéchelle(quelques kms) qu'à macro-échelle (quelques centaines de kms). / Nowadays, C and Ku bands used for fixed SATCOM systems are totally congested. However, the demand of the end users for high data rate multimedia services is increasing. Consequently, the use of higher frequency bands (Ka: 20 GHz and Q/V 40/50 GHz) is under investigation. For frequencies higher than 5 GHz, radiowave propagation is strongly affected by tropospheric attenuation. Among the different contributors, rain is the most significant. To compensate the deterioration of the propagation channel, Fade Mitigation Techniques (FMT) are used. The lack of experimental data needed to optimize the real-time control loops of FMT leads tothe use of rain attenuation and total attenuation time series synthesizers. The manuscript is a compilation of five articles. The first contribution is dedicated to the temporal modelling of total impairments. The second article aims at providing significant improvements on the rain attenuation time series synthesizer recommended by ITU-R. The last three contributions are a critical analysis and a modelling of the variability observed on the 1st order statistics used to validate propagation channel models. The variance of the statistical estimator of the complementary cumulative distribution functions of rainfall rate and rain attenuation is highlighted. A worldwide model parameterized in compliance with propagation measurements is proposed. It allows the confidence intervals to be estimated and the risk on a required availability associated with a given propagation margin prediction to be quantified. This approach is extended to the variability of joint statistics. It allows the impact of site diversity techniques on system performances at small scale (few kms) and large scale (few hundred of kms) to be evaluated.
9

Comparison of the 1st and 2nd order Lee–Carter methods with the robust Hyndman–Ullah method for fitting and forecasting mortality rates

Willersjö Nyfelt, Emil January 2020 (has links)
The 1st and 2nd order Lee–Carter methods were compared with the Hyndman–Ullah method in regards to goodness of fit and forecasting ability of mortality rates. Swedish population data was used from the Human Mortality Database. The robust estimation property of the Hyndman–Ullah method was also tested with inclusion of the Spanish flu and a hypothetical scenario of the COVID-19 pandemic. After having presented the three methods and making several comparisons between the methods, it is concluded that the Hyndman–Ullah method is overall superior among the three methods with the implementation of the chosen dataset. Its robust estimation of mortality shocks could also be confirmed.

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