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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.
251

Redes sociais e a l?gica do desvio comportamental em rela??o ?s normas de trabalho / Social networks and the logic of deviance about work norns

Burlamaqui, Nestor Medeiros Filgueira 23 March 2012 (has links)
Made available in DSpace on 2014-12-17T14:20:06Z (GMT). No. of bitstreams: 1 NestorMFB_DISSERT.pdf: 1580506 bytes, checksum: 2c3d6905b4637985a9bbe9946eeb948a (MD5) Previous issue date: 2012-03-23 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / This paper aim to check a hypothesis that assumes several behaviors related to social work norm?s obeying as a phenomenon that can be explained by actor?s social network structure and the rational choice processes related to the social norm inside that network, principally the payoff?s analysis received by the closest actors, or neighbors, at a social situation. Taking the sociological paradigm of rational action theory as a basis, the focus is on a debate about the logic of social norms, from ?mile Durkheim?s method to Jon Elster?s theory, but also including social network analysis?s variables according to Robert Hanneman; and also Vilfredo Pareto?s constants related to human sociability, at the aim to detect elements that can help the scholars to develop an agent based model which could explain the sociological problem of deviance by a better way than the common sense?s view about morality and ethics at a social work environment / Este trabalho pretende verificar a hip?tese de que a ado??o de comportamentos de obedi?ncia ou desobedi?ncia a norma social de trabalho pode ser explicada pela posi??o estrutural dos indiv?duos numa rede social e pelos processos racionais relevantes ? norma dentro desta rede; especialmente no tocante ? avalia??o de puni??es e recompensas recebidas pelas pessoas com as quais se tem mais contato no ambiente social em quest?o. Adotando o paradigma da sociologia da a??o, o foco ? o debate a respeito de uma l?gica das normas sociais a partir de ?mile Durkheim e que chega at? Jon Elster, mas tamb?m inclui uma explora??o do conceito de res?duos de Vilfredo Pareto recorrendo, dessa forma, ?s constantes comportamentais relacionadas ao desvio e ? sociabilidade humana e nos utilizando de medidas da an?lise de redes sociais de acordo com a obra de Robert Hanneman, no objetivo de detectar elementos necess?rios ao desenvolvimento de um modelo matem?tico explicativo que possa ajudar aos pesquisadores a compreender o problema do desvio comportamental relacionado ?s normas sociais de forma mais eficaz do que o recurso a eventuais fatores utilizados pelo senso comum, como princ?pios morais ou valores ?ticos e, no caso abordado, um eventual senso de responsabilidade no ambiente de trabalho
252

A dinâmica da percepção de qualidade em serviços estéticos sob uma perspectiva diádica

Zimbres, Rubens de Almeida 02 June 2009 (has links)
Made available in DSpace on 2016-03-15T19:31:19Z (GMT). No. of bitstreams: 1 Rubens de Almeida Zimbres.pdf: 953627 bytes, checksum: 788a11f034cfb7d55e50c105894ec1f3 (MD5) Previous issue date: 2009-06-02 / Wolfram Research, Inc. / The main goal of this thesis was to verify the influence of clients and providers role clarity in quality perception of esthetic services. Starting from a dyadic perspective, we studied how interactions during service cycle clarify roles of its participants, generating cognitive and emotional involvement, thus influencing quality perception and behavioral intentions. We did a quali-quantitative research, and had developed a scale for measuring the constructs. We evaluated psychometric properties of the scale and results suggest that relationships proposed and the scale for measuring constructs are valid. Results also show that there are perception discrepancies related to quality criteria among clients and providers. The use of control variables allowed to understand better clients and providers idiosyncrasies. After data analysis, we developed an artificial society based in cellular automata concept. Simulation results allowed to understand information diffusion in the social network and may be useful for service cycle management and development of Marketing strategies based in market segmentation. / A presente tese teve como objetivo verificar a influência da clareza do papel de clientes e provedores de serviços estéticos na percepção de qualidade dos mesmos. Partindo de uma perspectiva diádica, estudou-se como as interações durante o ciclo de serviço esclarecem os papéis dos participantes do mesmo, gerando envolvimento cognitivo e emocional, e influenciando assim a percepção de qualidade de serviço e as intenções comportamentais. Foi realizada uma pesquisa quali-quantitativa longitudinal, onde foram desenvolvidas escalas para mensuração dos construtos estudados. Foram avaliadas as propriedades psicométricas da escala desenvolvida e os resultados sugerem que as relações propostas e a escala desenvolvida apresentam validade. Os resultados também mostram que existem discrepâncias de percepção com relação aos critérios de qualidade entre clientes e provedores e o uso de variáveis de controle permitiu aprofundar o conhecimento das idiossincrasias de clientes e provedores. Após a análise dos dados, procedeu-se à construção de uma sociedade artificial baseada no conceito de autômatos celulares. Os resultados da simulação permitiram entender melhor a dinâmica de evolução de opiniões na rede social estudada, podendo ser úteis para gestão do ciclo de serviço e desenvolvimento de estratégias de Marketing baseadas em segmentação de mercado.
253

METODOLOGIA SEMI-AUTOMÁTICA PARA RECONSTRUÇÃO 3D DE SÓLIDOS GEOMÉTRICOS BASEADA EM IMAGEM / METHODOLOGY SEMI-AUTOMATIC 3D FOR RECONSTRUCTION OF SOLID GEOMETRY BASED IMAGE

Almeida, Irlandino Oliveira 17 September 2007 (has links)
Made available in DSpace on 2016-08-17T14:53:12Z (GMT). No. of bitstreams: 1 Irlandino Almeida.pdf: 795180 bytes, checksum: 9f8896e26b58665bad7d75b665940404 (MD5) Previous issue date: 2007-09-17 / We present a semi-automatic methodology for three-dimensional reconstruction using an image-based modeling environment. This is done through an initial camera calibration step that makes possible to the viewer, identify objects in the 2D acquired image and them get its position from the camera parameters. This methodology can be applied in the real word model reconstruction like electric and industry installations. / Apresentamos uma metodologia semi-automática para reconstrução tridimensional utilizando um ambiente de modelagem no qual o usuário, a partir de uma determinada imagem e de pontos nela selecionados com seu correspondente no espaço do mundo, realiza a calibração da câmera. Após este processo, a cena poderá ser composta a partir de objetos pré-estabelecidos fornecidos pelo ambiente de modelagem tridimensional baseado na imagem. Esta metodologia pode ser aplicada na reconstrução de modelos do mundo real, como instalações elétricas e industriais.
254

Infrared image-based modeling and rendering

Wretstam, Oskar January 2017 (has links)
Image based modeling using visual images has undergone major development during the earlier parts of the 21th century. In this thesis a system for automated uncalibrated scene reconstruction using infrared images is implemented and tested. An automated reconstruction system could serve to simplify thermal inspection or as a demonstration tool. Thermal images will in general have lower resolution, less contrast and less high frequency content as compared to visual images. These characteristics of infrared images further complicates feature extraction and matching, key steps in the reconstruction process. In order to remedy the complication preprocessing methods are suggested and tested as well. Infrared modeling will also impose additional demands on the reconstruction as it is of importance to maintain thermal accuracy of the images in the product. Three main results are obtained from this thesis. Firstly, it is possible to obtain camera calibration and pose as well as a sparse point cloud reconstruction from an infrared image sequence using the suggested implementation. Secondly, correlation of thermal measurements from the images used to reconstruct three dimensional coordinates is presented and analyzed. Lastly, from the preprocessing evaluation it is concluded that the tested methods are not suitable. The methods will increase computational cost while improvements in the model are not proportional. / Bildbaserad modellering med visuella bilder har genomgått en stor utveckling under de tidigare delarna av 2000-talet. Givet en sekvens bestående av vanliga tvådimensionella bilder på en scen från olika perspektiv så är målet att rekonstruera en tredimensionell modell. I denna avhandling implementeras och testas ett system för automatiserad okalibrerad scenrekonstruktion från infraröda bilder. Okalibrerad rekonstruktion refererar till det faktum att parametrar för kameran, såsom fokallängd och fokus, är okända och enbart bilder används som indata till systemet. Ett stort användingsområde för värmekameror är inspektion. Temperaturskillnader i en bild kan indikera till exempel dålig isolering eller hög friktion. Om ett automatiserat system kan skapa en tredimensionell modell av en scen så kan det bidra till att förenkla inspektion samt till att ge en bättre överblick. Värmebilder kommer generellt att ha lägre upplösning, mindre kontrast och mindre högfrekvensinnehåll jämfört med visuella bilder. Dessa egenskaper hos infraröda bilder komplicerar extraktion och matchning av punkter i bilderna vilket är viktiga steg i rekonstruktionen. För att åtgärda komplikationen förbehandlas bilderna innan rekonstruktionen, ett urval av metoder för förbehandling har testats. Rekonstruktion med värmebilder kommer också att ställa ytterligare krav på rekonstruktionen, detta eftersom det är viktigt att bibehålla termisk noggrannhet från bilderna i modellen. Tre huvudresultat erhålls från denna avhandling. För det första är det möjligt att beräkna kamerakalibrering och position såväl som en gles rekonstruktion från en infraröd bildsekvens, detta med implementationen som föreslås i denna avhandling. För det andra presenteras och analyseras korrelationen för temperaturmätningar i bilderna som används för rekonstruktionen. Slutligen så visar den testade förbehandlingen inte en förbättring av rekonstruktionen som är propotionerlig med den ökade beräkningskomplexiteten.
255

Erweiterung des CRC-Karten-Konzeptes um Rollen

Hamann, Markus 11 January 2018 (has links) (PDF)
Die rollenbasierte Modellierung ist ein aktueller Forschungszweig, welcher Verfahren für die Analyse und die Lehre benötigt. Zu diesem Zweck präsentiert die Arbeit eine Erweiterung des klassischen, objektorientierten CRC-Karten-Verfahrens um rollenbasierte Konzepte. Diese basiert auf grundlegenden Eigenschaften rollenbasierter Elemente, wie Rollen, Objekte und Kontexte, welche modular in das CRC-Karten- Verfahren eingebunden werden. Weiterhin soll anhand einer empirische Studie ermittelt werden, wie gut das rollenerweiterte R-CRC-Karten-Verfahren für die Aufgaben in Analyse und Lehre geeignet ist. Das R-CRC-Karten-Verfahren soll letztendlich eine effiziente Möglichkeit bieten, Problemstellungen rollenbasiert zu analysieren und rollenbasierte Konzepte in der Lehre zu vermitteln.
256

An Agent-Based Model of Institutional Life-Cycles

Wäckerle, Manuel, Rengs, Bernhard, Radax, Wolfgang January 2014 (has links) (PDF)
We use an agent-based model to investigate the interdependent dynamics between individual agency and emergent socioeconomic structure, leading to institutional change in a generic way. Our model simulates the emergence and exit of institutional units, understood as generic governed social structures. We show how endogenized trust and exogenously given leader authority influences institutional change, i.e., diversity in institutional life-cycles. It turns out that these governed institutions (de)structure in cyclical patterns dependent on the overall evolution of trust in the artificial society, while at the same time, influencing this evolution by supporting social learning. Simulation results indicate three scenarios of institutional life-cycles. Institutions may, (1) build up very fast and freeze the artificial society in a stable but fearful pattern (ordered system); (2) exist only for a short time, leading to a very trusty society (highly fluctuating system); and (3) structure in cyclical patterns over time and support social learning due to cumulative causation of societal trust (complex system).
257

Simulation à base d'agents de la propagation de la Schistosomiase : une approche de composition et de déploiement de modèles / Agent-based simulation of the spread of schistosomiasis : a composition and deployment approach of models

Cissé, Papa Alioune 09 December 2016 (has links)
Nos travaux de thèse portent sur la modélisation et la simulation à base d'agents de systèmes complexes, appliquées au phénomène de propagation de la Schistosomose. Plus particulièrement, nous nous sommes intéressés aux aspects spatiaux et sociaux de la propagation de cette maladie, en utilisant une approche de couplage de modèles à base d'agents. En effet, nous avons initialement étudié la modélisation mathématique de la Schistosomose et la complexité du phénomène de sa propagation. Ce qui nous a permis d'identifier deux dynamiques épidémiologiques (dynamiques spatiale et sociale) sous-jacentes à la propagation de la Schistosomose pour lesquelles, les modèles mathématiques présentent des limites. Cette problématique nous a poussés à étudier isolément ces deux dynamiques et à proposer un modèle multi-agents pour chacune d'elles. Ces deux modèles à base d'agents, représentant deux dynamiques complémentaires d'un même système, ont été implémentés selon des formalismes et des plateformes différentes : un modèle dans GAMA, une plateforme de simulation à base d'agents ; et un autre dans JASON, une plateforme de programmation d'agents BDI (Belief, Desire, Intention). Le modèle GAMA implémente l'aspect comportemental (pour la dynamique spatiale) qui se penche sur la réactivité des individus face à l'environnement physique et le suivi de l'infection. Le modèle JASON implémente l'aspect décisionnel (pour la dynamique sociale) qui introduit la dimension cognitive et mentale des individus en assurant leur capacité de décision et de sélection qui sont déterminées par leur environnement social, culturel, économique, etc. Pour assurer la composition des deux modèles, nous avons proposé une solution de couplage (par Co-simulations) des deux plateformes GAMA et JASON. Nous avons finalement expérimenté le modèle avec un cas de dynamique de propagation de la maladie à Niamey (au Niger) pour lequel les données étaient accessibles. / Our thesis work focuses on agent-based modeling and simulation of complex systems, applied to the spread of schistosomiasis. Specially, we were interested in the spatial and social aspects of the spread of the disease, using an agent-based coupling approach of models.Indeed, we initially studied the mathematical modeling of schistosomiasis and the complexity of its propagation, which allowed us to identify two epidemiological dynamics (spatial and social dynamics) underlying the spread of schistosomiasis for which mathematical models have limits. This problematic led us to study separately these two dynamics and propose an agent-based model for each. These two agent-based models, representing two complementary dynamics of a system, were implemented according different formalisms and different platforms: one model on GAMA (an agent-based simulation platform); and another on JASON (a programming platform of BDI agents). The GAMA model implements the behavioral aspect (for the spatial dynamic) that focuses on individuals reactivity with regards to the physical environment, and the monitoring of the infection. The JASON model implements the decisional aspect (for the social dynamic) that introduces the cognitive and mental dimension of individuals, ensuring their decision and selection capacities which are determined by their social, cultural and economic environment. To ensure the composition of the two models, we proposed an agent-based coupling solution (co-simulation) of the two platforms (GAMA and JASON). We finally experienced the model with a case of dynamic spread of the disease in Niamey (Niger) for which data were available.
258

Methods for image-based 3-D modeling using color and depth cameras

Ylimäki, M. (Markus) 05 December 2017 (has links)
Abstract This work addresses the problems related to three-dimensional modeling of scenes and objects and model evaluation. The work is divided into four main parts. At first, the work concentrates on purely image-based reconstruction while the second part presents a modeling pipeline based on an active depth sensor. Then, the work introduces methods for producing surface meshes from point clouds, and finally, a novel approach for model evaluation is presented. In the first part, this work proposes a multi-view stereo (MVS) reconstruction method that takes a set of images as an input and outputs a model represented as a point cloud. The method is based on match propagation, where a set of initial corresponding points between images is expanded iteratively into larger regions by searching new correspondences in the spatial neighborhood of the existing ones. The expansion is implemented using a best-first strategy, where the most reliable match is always expanded first. The method produces comparable results with the state-of-the-art but significantly faster. In the second part, this work presents a method that merges a sequence of depth maps into a single non-redundant point cloud. In the areas, where the depth maps overlap, the method fuses points together by giving more weight to points which seem to be more reliable. The method overcomes its predecessor both in accuracy and robustness. In addition, this part introduces a method for depth camera calibration. The method develops on an existing calibration approach which was originally designed for the first generation Microsoft Kinect device. The third part of the thesis addresses the problem of converting the point clouds to surface meshes. The work briefly reviews two well-known approaches and compares their ability to produce sparse mesh models without sacrificing accuracy. Finally, the fourth part of this work describes the development of a novel approach for performance evaluation of reconstruction algorithms. In addition to the accuracy and completeness, which are the metrics commonly used in existing evaluation benchmarks, the method also takes the compactness of the models into account. The metric enables the evaluation of the accuracy-compactness trade-off of the models. / Tiivistelmä Tässä työssä käsitellään näkymän tai esineen kolmiulotteista mallintamista ja tulosten laadun arviointia. Työ on jaettu neljään osaan. Ensiksi keskitytään pelkästään valokuvia hyödyntävään mallinnukseen ja sitten esitellään menetelmä syvyyskamerapohjaiseen mallinnukseen. Kolmas osa kuvaa menetelmiä verkkomallien luomiseen pistepilvestä ja lopuksi esitellään menetelmä mallien laadun arviointiin. Ensimmäisessä osassa esitellään usean kuvan stereoon perustuva mallinnusmenetelmä, joka saa syötteenä joukon valokuvia ja tuottaa kuvissa näkyvästä kohteesta pistepilvimallin. Menetelmä perustuu vastinpisteiden laajennukseen, jossa kuvien välisiä pistevastaavuuksia laajennetaan iteratiivisesti suuremmiksi vastinalueiksi hakemalla uusia vastinpistepareja jo löydettyjen läheisyydestä. Laajennus käyttää paras ensin -menetelmää, jossa luotettavin pistevastaavuus laajennetaan aina ensin. Menetelmä tuottaa vertailukelpoisia tuloksia johtaviin menetelmiin verrattuna, mutta merkittävästi nopeammin. Toisessa osassa esitellään menetelmä, joka yhdistää joukon syvyyskameralla kaapattuja syvyyskarttoja yhdeksi pistepilveksi. Alueilla, jotka sisältävät syvyysmittauksia useasta syvyyskartasta, päällekkäiset mittaukset yhdistetään painottamalla luotettavammalta vaikuttavaa mittausta. Menetelmä on tarkempi kuin edeltäjänsä ja toimii paremmin kohinaisemmalla datalla. Lisäksi tässä osassa esitellään menetelmä syvyyskameran kalibrointiin. Menetelmä kehittää jo olemassa olevaa kalibrointityökalua, joka alun perin kehitettiin ensimmäisen sukupolven Microsoft Kinect laitteelle. Väitöskirjan kolmas osa käsittelee pintamallin luomista pistepilvestä. Työ esittelee kaksi hyvin tunnettua menetelmää ja vertailee niiden kykyä luoda harvoja, mutta edelleen tarkkoja malleja. Lopuksi esitellään uudenlainen menetelmä mallinnusmenetelmien arviointiin. Tarkkuuden ja kattavuuden lisäksi, jotka ovat yleisimmät arvioinnissa käytetyt metriikat, menetelmä ottaa huomioon myös mallin pistetiheyden. Metriikan avulla on mahdollista arvioida kompromissia mallin tarkkuuden ja tiheyden välillä.
259

[en] BOOLEAN OPERATIONS ON POINT-BASED MODELS / [pt] OPERAÇÕES BOOLEANAS NA MODELAGEM POR PONTOS

HELOISA REIS LEAL 19 January 2005 (has links)
[pt] Operações booleanas em modelagem 3D são usadas para criar novos modelos ou para modificá-los. Na maioria dos tipos de representação de objetos 3D, estas operações são bastante complexas. Nos últimos anos tem sido muito explorado um novo tipo de modelagem, a modelagem por pontos, que apresenta muitas vantagens em relação às outras representações como maior simplicidade e eficiência. Dois trabalhos exploram as operações booleanas na modelagem por pontos, o trabalho de Adams e Dutré e o trabalho de Pauly et. al. Dada a grande importância deste novo tipo de modelagem e do uso de operações booleanas, esta dissertação apresenta uma introdução à modelagem por pontos, implementa o algoritmo proposto em Adams e Dutré com algumas melhorias e o compara com o método de Pauly et. al. / [en] Boolean operations are used to create or modify models. These operations in the majority of 3D object representations are very complex. In the last years a significant trend in computer graphics has been the shift towards point sampled 3D models due to their advantages over other representations, such as simplicity and efficiency. Two recent works present algorithms to perform interactive boolean operations on point-based models: the work by Adams and Dutré and the work by Pauly et. Al.. Due to great importance of this novel representation and of the use of boolean operations, the present work makes an introduction to point-based representation, implements the algorithm proposed by Adams and Dutré with some improvements, and compares this implementation with the work by Pauly et. al..
260

Formal and exact reduction for differential models of signalling pathways in rule-based languages / Réduction formelle et exacte de modèles différentiels de voies de signalisation en Kappa

Camporesi, Ferdinanda 23 January 2017 (has links)
Le comportement d'une cellule dépend de sa capacité à recevoir, propager et intégrer des signaux, constituant ainsi des voies de signalisations. Les protéines s'associent entre elles sur des sites de liaisons, puis modifient la structure spatiale des protéines voisines, ce qui a pour effet de cacher ou de découvrir leurs autres sites de liaisons, et donc d'empêcher ou de faciliter d'autres interactions. En raison du grand nombre de différents complexes bio-moléculaires, nous ne pouvons pas écrire ou générer les systèmes différentiels sous-jacents. Les langages de réécritures de graphes à sites offrent un bon moyen de décrire ces systèmes complexes. Néanmoins la complexité combinatoire resurgit lorsque l'on cherche à calculer de manière effective ce comportement. Ceci justifie l'utilisation d'abstractions. Nous proposons deux méthodes pour réduire la taille des modèles de voies de signalisation, décrits en Kappa. Ces méthodes utilisent respectivement la présence de symétries parmi certains sites et le fait que certaines corrélations entre l'état de différentes parties des complexes biomoléculaires n'ont pas d'impact sur la dynamique du système global. Des sites qui ont la même capacité d'interaction sont liés par une relation de symétrie. Nous montrons que cette relation induit une bisimulation qui peut être utilisée pour réduire la taille du modèle initial. L'analyse du flot d'information détecte les parties du système qui influencent le comportement de chaque site. Ceci nous autorise à couper les espèces moléculaires en petits morceaux pour écrire un nouveau système. Enfin, nous montrons comment raffiner cette analyse pour tenir compte d'information contextuelle. Les deux méthodes peuvent être combinées. La solution analytique du modèle réduit est la projection exacte de la solution originelle. Le calcul du modèle réduit se fait au niveau des règles, en évitant l'exécution du modèle initial. / The behaviour of a cell is driven by its capability to receive, propagate and communicate signals. Proteins can bind together on some binding sites. Post-translational modifications can reveal or hide some sites, so new interactions can be allowed or existing ones can be inhibited. Due to the huge number of different bio-molecular complexes, we can no longer derive or integrate ODE models. A compact way to describe these systems is supplied by rule-based languages. However combinatorial complexity raises again when one attempt to describe formally the behaviour of the models. This motivates the use of abstractions. We propose two methods to reduce the size of the models, that exploit respectively the presence of symmetries between sites and the lack of correlation between different parts of the system. The symmetries relates pairs of sites having the same capability of interactions. We show that this relation induces a bisimulation which can be used to reduce the size of the original model. The information flow analysis detects, for each site, which parts of the system influence its behaviour. This allows us to cut the molecular species in smaller pieces and to write a new system. Moreover we show how this analysis can be tuned with respect to a context. Both approaches can be combined. The analytical solution of the reduced model is the exact projection of the original one. The computation of the reduced model is performed at the level of rules, without the need of executing the original model.

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