Made available in DSpace on 2014-06-12T15:59:54Z (GMT). No. of bitstreams: 2 arquivo5705_1.pdf: 963823 bytes, checksum: 471ae4b6b6c49b8c08bc92915c2f412b (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2006 / Algumas tecnologias têm se mostrado promissoras como meios de auxiliar na tomada de decisões estratégicas, destacando-se Sistemas de Informação Geográfica(SIG), Data Warehouses( DW) e On-Line Analytical Processing(OLAP), que constituem mecanismos úteis para suporte à decisão e normalmente atuam de forma independente. Devido à natureza diversificada das informações, uma abordagem unindo as funcionalidades presentes em cada ambiente aponta como uma solução mais adequada ao cenário atual, resultando numa poderosa ferramenta para análise dos dados ao considerar simultaneamente características presentes nos dados analíticos e aspectos específicos dos dados geográficos. O presente trabalho demonstrou que as limitações tecnológicas existentes pelo fato de não haver uma linguagem de consulta única, que permita o uso de operações geográficomultidimensionais para acessar um Data Warehouse Geográfico, podem ser superadas. Através da união de linguagens de consulta distintas e que operam individualmente, ele permitiu a realização do processamento geográfico-multidimensional. Para lidar com este contexto, os algoritmos Restrição Multidimensional-Geográfica e Restrição Geográfico-Multidimensional foram propostos e validados. Um engenho para processamento geográfico-multidimensional que implementava estes algoritmos foi desenvolvido a partir de extensões de ferramentas disponibilizadas como Software Livre. Também foi elaborado um protótipo com interface web que estendia uma ferramenta OLAP existente e incorporava a possibilidade de executar consultas geográfico-multidimensionais de mapeamento, permitindo assim a visualização dos resultados das requisições de forma tabular, gráfica ou através de mapas. Por fim, um DWG com dados sobre o sistema público de saúde brasileiro foi construído e utilizado como base em uma análise estatística conduzida para verificar qual, dentre os dois algoritmos propostos e considerando as situações em que eles produzem o mesmo resultado, tinha melhor desempenho. A avaliação experimental mostrou que o algoritmo Restrição Geográfico-Multidimensional é o mais indicado, visto que apresentou melhor desempenho em situações consideradas mais realistas para consultas a um DWG

L'échocardiographie est la modalité d'imagerie la plus utilisée pour évaluer la morphologie et la fonction cardiaque. Il s'agit d'un outil non invasif pour le diagnostic et l'évaluation des maladies cardiaques et il permet en outre de surveiller la réponse au traitement. Cependant, la quantification des événements cardiaques rapides demeure un défi avec la cadence d’imagerie actuellement réalisable, en particulier dans des applications telles que l'échocardiographie d'effort. De plus, cette limitation devient plus prononcée en imagerie 3D conventionnelle focalisée en raison du temps nécessaire pour insonifier et acquérir un volume complet. Le fait que l’on puisse actuellement atteindre au mieux ~20 volumes par seconde est l'une des raisons qui limitent son utilisation courante dans la pratique clinique. Des améliorations dans ce domaine permettraient d'exploiter l'important potentiel de l'imagerie 3D pour la quantification complète de la déformation cardiaque.Dans ce contexte, l'objectif de cette thèse était de développer des méthodes à haute cadence d'images et de tester leur performance dans des conditions réalistes visant la prise de décision pour une transition vers la pratique clinique. Pour atteindre cet objectif, des expériences in vitro et in vivo ont été menées en utilisant l'imagerie 2D et 3D. Notre première contribution a été une comparaison 2D entre deux modalités à haute cadence d'images en termes de qualité d'image et de performance d'estimation de mouvement. Motivés par nos résultats 2D mais surtout par le défi d'implémenter le MLT dans la pratique, nous avons étendu cette approche en 3D. Nous avons étudié la faisabilité de la MLT 3D dans des conditions statiques et dynamiques. Enfin, comme l’évaluation de nouvelles approches dans des conditions physiologiques de flux complexes constitue un pas en avant vers la transition clinique, notre troisième contribution a consisté à valider des modalités 2D et 3D à haut cadence d'images sur un fantôme du vortex / Echocardiography is the most widely used imaging modality for assessing cardiac morphology and function. It does provide a non-invasive tool in diagnosis and assessment of heart diseases and it allows, in addition, monitoring the response to the treatment. However, quantifying fast cardiac events remains a challenge when using the current achievable frame rate, especially in applications such as stress-echocardiography. Moreover, this limitation becomes more pronounced in 3D conventional focused imaging due to the time needed to insonify and acquire a full volume. The fact that only ~20 volumes per second can currently be achieved is one of the reasons restricting its common usage in clinical practice. Improvements in this field would allow exploiting the important potential of 3D imaging in providing a full quantification of cardiac deformation.In this context, the aim of this thesis was to develop high frame rate methods and to test their performance in realistic conditions aiming decision making towards clinical translation. To achieve this objective, both in vitro and in vivo experiments were conducted using 2D and 3D imaging. Our first contribution was a 2D comparison between two high frame rate modalities in terms of image quality and motion estimation performance. Motivated by our 2D results but especially by the challenge of implementing MLT in practice, we extended this approach to 3D. We studied the feasibility of 3D MLT in both static and dynamic conditions. Finally, as testing novel approaches in physiological complex flows conditions is a step forward towards clinical translation, our third contribution was to validate 2D and 3D high frame rate modalities on a ring vortex phantom

Die vorliegende Arbeit bezieht sich auf die gewerkschaftliche Jugendbildungsarbeit (JBA) als Ausdruck der politischen Bildung von jungen Erwachsenen bzw. ihre Aus- und Weiterbildung zu gewerkschaftlichen Funktionären. Als Gegenstand der Untersuchung ist ihre Verbindung zum gesamtgesellschaftlichen Zusammenhang von Interesse, da die JBA auf Grundlage einer kritischen Theorie der Gesellschaft, beeinflusst durch die Frankfurter Schule, die Kritik der politischen Ökonomie von Karl Marx sowie durch diverse marxistische Theoretiker analysiert wird. Ziel dieser Analyse ist die Verwirklichung von drei grundsätzlichen Ansprüchen. Zum einen die Vermittlung von Informationen über den historischen Entwicklungsverlauf der JBA, um ihren Diskurs unter Berücksichtigung der vereinzelten historischen Epochen und Situationen dazustellen. Diese Darstellung bietet die Grundlage, von der aus anhand des erkenntnisleitenden Interesses – der Emanzipation von Herrschaft – das zweite, das zentrale Anliegen der vorliegenden Arbeit, die Falsifikation bzw. die Verifikation ihrer Hypothese – die JBA als „ungelebte Emanzipation“ – verfolgt wird. Die Untersuchung geht zu diesem Zweck der Frage der Politisierung bzw. Entpolitisierung der JBA nach, um anhand dieser Fragestellung den historischen Entwicklungsverlauf der JBA sowie der in ihr kommunizierten politischen Ansprüche zu untersuchen. Ziel ist es, die gewerkschaftlichen Positionen qualitativ zu bestimmen bzw. eine Aussage über ihre politisierende bzw. entpolitisierende Wirkung auf die JBA zu treffen. / The work here refers primarily to the “Jugendbildungsarbeit”, JBA (Youth Education Work) as an expression of the political education of young adults in terms of their education and training as trade union officials. The subject of the investigation is its connection with an overall social coherence of interest, which in turn is analyzed on the basis of a critical theory of society, influenced by the “Frankfurter School”, the criticism of the political economy of Karl Marx and other Marxist theoreticians. This analysis strives to realize three basic goals. The first two are: Providing information concerning the course of JBA development in order to represent that information with regard to each of the historic epochs and situations. That representation is the starting point, from which follows, based on the cognition-inducing interest, the emancipation from rule, the second central concern of the work, namely the falsification and in fact verification of its hypothesis of the JBA as „unfulfilled emancipation“. To do that the question of the politicization or depoliticizing of the JBA is examined, in order, based on this line of questioning, to investigate the historical course of development of the JBA as well as the political demands it communicates. The goal is to qualitatively determine the trade union positions and to formulate a statement about the politicization or depoliticizing effect of the JBA.

Trabalhos anteriores sobre a síntese de imagens de difusão por ressonância magnética se limitaram a estudos sobre estruturas microscópicas, menores que as dimensões típicas de um voxel (e.g., [BF08] [BF13] [LFS + 10] e [BA94]). Isto decorre em parte devido às metodologias utilizadas, que têm como ponto em comum serem simulações de tipo Monte Carlo, nas quais os elementos mínimos da simulação são as partículas de água. Portanto o custo computacional destas simulações é proporcional ao número de partículas a simular, e isto limita os volumes que podem ser simulados a tamanhos microscópicos. Propomos uma metodologia alternativa, que utiliza a imagem T 2 de uma amostra para sintetizar imagens de difusão por ressonância magnética. Os elementos mínimos desta nova metodologia são os pontos da imagem T 2 , e portanto seu custo computacional é proporcional à resolução da imagem T 2 utilizada, o que permite a síntese a partir de amostras de qualquer tamanho físico. Estas sínteses são realizadas por meio da integração numérica da equação do artigo seminal de Stejskal e Tanner [ST65] que relaciona a atenuação do sinal de ressonância magnética devida à difusão com os parâmetros da sequência de pulsos PGSE. Usamos os parâmetros típicos dessa sequência (b, gamma, tau\', g 0, g, delta e Delta), que podem ser configurados explicitamente em máquinas de ressonância magnética, para calcular valores do coeficiente de difusão aparente D em direções arbitrárias. Desenvolvemos software, disponibilizado [Bor] por licença GPL [Fou07], para realizar estas simulações, e para especificar uma máscara de direções, útil para modelar a difusão de uma amostra. Estas ferramentas permitem o estudo sistemático das variações dos parâmetros na síntese de imagens de difusão por ressonância magnética. Apresentamos um estudo de um fantoma de capilares imersos em água, exemplificando como utilizar as ferramentas para investigar a influência destes parâmetros na difusão da água da amostra. / Previous work on the synthesis of diffusion-weighted magnetic resonance imaging are limited to microscopic structures, smaller than the typical dimensions of a single voxel (e.g., [BF08] [BF13] [LFS + 10] and [BA94]). This is consequence, in part, of the methodologies used, that have in common the adoption of Monte Carlo simulation strategies, in which the minimal elements of simulation are the water particles. Therefore the computational cost of these simulations is proportional to the number of particles to simulate, and this limits the volume to be simulated to microscopic sizes. We propose a novel methodology, that uses the T 2 image from a sample to synthesize diffusion-weighted magnetic resonance images. The mininal elements of this novel methodology are the points of the T 2 image, and therefore its computational cost is proportional to the resolution of the T 2 image to be used, which allows the synthesis from samples of any physical size. These syntheses are made through numerical integration of the equation from the seminal article by Stejskal and Tanner [ST65] that relates the attenuation of the magnetic resonance signal due to diffusion to the parameters of the PGSE pulse sequence. We use the typical parameters of this sequence (b, gamma, tau\', g 0, g, delta and Delta), that can be explicitly configured in magnetic resonance machines, to calculate apparent diffusion coefficients D in arbitrary directions. We developed software, available [Bor] through GPL license [Fou07], to run these simulations, and to specify a mask of directions useful to model diffusion. These tools allow the systematic study of parameter variation in the synthesis of diffusion-weighted magnetic resonance images. We present a case study of a phantom made of capillary tubes immersed in water, to exemplify the use of these tools and how to investigate the influence of parameter variation on diffusion in the sample.

Neuartige Kontraste in der Magnetresonanz-Bildgebung wie Diffusionswichtung (DW) oder Magnetisierungstransfer (MT) finden zunehmend Verwendung in der klinischen Diagnostik. Während bei der DW der Kontrast durch unterschiedliche Diffusionseigenschaften von Wassermolekülen in Gewebe verursacht wird, wird der MT-Kontrast durch unterschiedliche Anteile an gebundenen und freien Protonen im Gewebe beeinflusst. Der MT basiert auf einer selektiven Sättigung der an Makromolekülen gebundenen Protonen und dem anschließenden Transfer dieser Sättigung der Magnetisierung auf freie Protonen. Dieser Austausch führt zu einem Abfall der Signalsättigung von freien Protonen. Diese Methode besitzt das Potential, Rückschlüsse auf spezifische mikrostrukturelle Veränderung im Gewebe zu ziehen. In der vorliegenden Pilotstudie wurde ein neuer Parameter zur Beschreibung des MT-Kontrastes - die MT-Sättigung - auf ihr Potential untersucht,  Gewebeveränderungen in einem Teil der Basalganglien bei der sporadischen Creutzfeldt-Jakob-Erkrankung (sCJK) zu detektieren. Typische mikrostrukturelle Gewebeveränderungen bei der sCJK beinhalten die Ablagerungen pathologischer Prion-Proteine, spongiformen Umbau des Neuropils sowie astrozytäre Gliose und Nervenzellverlust. Anonymisierte klinisch-diagnostische MRT-Bilddaten (3D-FLASH, DWI) von 5 Patienten mit definitiver oder wahrscheinlicher sCJD wurden retrospektiv untersucht und mit denen altersangepasster gesunder Kontrollen verglichen. Mittels einer ROI-Analyse auf den MT-Karten wurden neben dem Caput des Ncl. caudatus, dem Putamen und dem Pulvinar auch MT-Werte in der Amygdala bestimmt. Im Gegensatz zum Pulvinar und zur Amygdala konnten mit dieser Methode im Ncl. caudatus und im Putamen Veränderungen aufgezeigt werden. Hier wurden im Vergleich zu einer gesunden Kontrollkohorte in beiden Strukturen signifikant niedrigere MT-Werte bei sCJK-Patienten gefunden. Eine Regressionsanalyse gegen die DW-MRT, dem etablierten diagnostischen Kriterium, ergab eine signifikante positive Korrelation von MT und mittlerer Diffusivität (MD), die auf einen Zusammenhang von erhöhten Diffusionsbarrieren und erhöhtem Wassergehalt schließen lässt. Diese Korrelation könnte auf mikrozystische Veränderungen im Neuropil zurückzuführen sein. Eine inverse Korrelation im Pulvinar sowohl in der erkrankten als auch in der gesunden Kohorte deutet dagegen auf inhärent strukturelle Barrieren hin, die die Diffusion dominierend einschränken. Die MT-Sättigung hat somit das Potential, als diagnostisches Kriterium bei der sCJK eingesetzt zu werden. Der Informationsgewinn kann hierdurch gesteigert werden, indem verschiedene quantitative MR-Techniken miteinander kombiniert werden.

Trabalhos anteriores sobre a síntese de imagens de difusão por ressonância magnética se limitaram a estudos sobre estruturas microscópicas, menores que as dimensões típicas de um voxel (e.g., [BF08] [BF13] [LFS + 10] e [BA94]). Isto decorre em parte devido às metodologias utilizadas, que têm como ponto em comum serem simulações de tipo Monte Carlo, nas quais os elementos mínimos da simulação são as partículas de água. Portanto o custo computacional destas simulações é proporcional ao número de partículas a simular, e isto limita os volumes que podem ser simulados a tamanhos microscópicos. Propomos uma metodologia alternativa, que utiliza a imagem T 2 de uma amostra para sintetizar imagens de difusão por ressonância magnética. Os elementos mínimos desta nova metodologia são os pontos da imagem T 2 , e portanto seu custo computacional é proporcional à resolução da imagem T 2 utilizada, o que permite a síntese a partir de amostras de qualquer tamanho físico. Estas sínteses são realizadas por meio da integração numérica da equação do artigo seminal de Stejskal e Tanner [ST65] que relaciona a atenuação do sinal de ressonância magnética devida à difusão com os parâmetros da sequência de pulsos PGSE. Usamos os parâmetros típicos dessa sequência (b, gamma, tau\', g 0, g, delta e Delta), que podem ser configurados explicitamente em máquinas de ressonância magnética, para calcular valores do coeficiente de difusão aparente D em direções arbitrárias. Desenvolvemos software, disponibilizado [Bor] por licença GPL [Fou07], para realizar estas simulações, e para especificar uma máscara de direções, útil para modelar a difusão de uma amostra. Estas ferramentas permitem o estudo sistemático das variações dos parâmetros na síntese de imagens de difusão por ressonância magnética. Apresentamos um estudo de um fantoma de capilares imersos em água, exemplificando como utilizar as ferramentas para investigar a influência destes parâmetros na difusão da água da amostra. / Previous work on the synthesis of diffusion-weighted magnetic resonance imaging are limited to microscopic structures, smaller than the typical dimensions of a single voxel (e.g., [BF08] [BF13] [LFS + 10] and [BA94]). This is consequence, in part, of the methodologies used, that have in common the adoption of Monte Carlo simulation strategies, in which the minimal elements of simulation are the water particles. Therefore the computational cost of these simulations is proportional to the number of particles to simulate, and this limits the volume to be simulated to microscopic sizes. We propose a novel methodology, that uses the T 2 image from a sample to synthesize diffusion-weighted magnetic resonance images. The mininal elements of this novel methodology are the points of the T 2 image, and therefore its computational cost is proportional to the resolution of the T 2 image to be used, which allows the synthesis from samples of any physical size. These syntheses are made through numerical integration of the equation from the seminal article by Stejskal and Tanner [ST65] that relates the attenuation of the magnetic resonance signal due to diffusion to the parameters of the PGSE pulse sequence. We use the typical parameters of this sequence (b, gamma, tau\', g 0, g, delta and Delta), that can be explicitly configured in magnetic resonance machines, to calculate apparent diffusion coefficients D in arbitrary directions. We developed software, available [Bor] through GPL license [Fou07], to run these simulations, and to specify a mask of directions useful to model diffusion. These tools allow the systematic study of parameter variation in the synthesis of diffusion-weighted magnetic resonance images. We present a case study of a phantom made of capillary tubes immersed in water, to exemplify the use of these tools and how to investigate the influence of parameter variation on diffusion in the sample.

The aim of this thesis is to present possibility to integrate Decision Support System with specialized system for statistical computing and provides easier way to analyze economics indicators using sophisticated statistical methods. The R project is complex set of applications, designated for manipulation, computing and graphical presentation of data sets. It is mostly used for statistical analysis and graphical presentations. It allows users to create new methods with language similar to S as well as using the default methods provided.

Durch Weiterentwicklungen der MR-Technologie hat die diffusionsgewichtete MRT in der Bildgebung des Abdomens zunehmend an Bedeutung gewonnen. Einige wenige Studien zeigten bereits vielversprechende Ergebnisse für den Einsatz der DWI in der Diagnostik und Verlaufsbeurteilung des Morbus Crohn. Ziel dieser Arbeit war es, zu untersuchen, ob die DWI zur Detektion entzündlicher Darmwandläsionen und extraluminaler Komplikationen bei pädiatrischen Patienten mit Morbus Crohn ebenso geeignet ist wie die kontrastmittelverstärkte MRT. Hierzu wurden retrospektiv die klinischen und MR-tomographischen Daten von 48 Kindern, Jugendlichen und jungen Erwachsenen mit Morbus Crohn sowie von 42 Kontrollpatienten ausgewertet, bei denen im Zeitraum zwischen Juli 2008 und Mai 2013 eine MRT-Untersuchung durchgeführt wurde. Aktuelle Befunde einer Ileokoloskopie waren als Referenz bei 60% der Morbus Crohn Patienten und bei etwa einem Drittel der Patienten der Kontrollgruppe vorhanden. Das Bestehen eines Morbus Crohn konnte bei 47 der insgesamt 48 Patienten anhand der diffusionsgewichteten Sequenzen und in 46 Fällen mittels der kontrastverstärkten T1w-Aufnahmen korrekt nachgewiesen werden. Extramurale Komplikationen wie Abszesse oder Fisteln konnten sowohl mittels DWI als auch durch die KM-MRT detektiert werden. Da die DWI weder eine intravenöse Kontrastmittelapplikation noch Atemanhaltetechniken erfordert, ist sie gerade bei pädiatrischen Patienten ein geeignetes Bildgebungsverfahren. Wegen der relativ geringen Ortsauflösung der diffusionsgewichteten Sequenzen sollte jedoch zusätzlich eine Standardsequenz, wie die T2-gewichtete HASTE-Sequenz, akquiriert werden. Nach den Ergebnissen dieser Studie ist die diffusionsgewichtete MRT zur Beurteilung der entzündlichen Veränderungen des Morbus Crohn sehr gut geeignet und besitzt das Potenzial, nicht nur ergänzend, sondern als Alternative zur KM-MRT zum Einsatz zu kommen. / The purpose of this retrospective study was to evaluate the detectability of inflammatory bowel lesions and of extramural complications with diffusion-weighted MRI (DWI), compared to contrast-enhanced MRI (CE-MRI), in pediatric patients with Crohn disease. The study included 48 children and young adults with Crohn disease and 42 matched controls who underwent routine MRI with DWI and contrast-enhanced T1-weighted sequences during a 5-year-period. Colonoscopy as reference standard was available in about two-thirds of the children with Crohn disease and in about one-third of controls. Overall diagnostic accuracy for identifying pediatric patients with inflammatory bowel lesions among patients and controls in our study was 99% (89/90) for DWI and 98% (88/90) for CE-MRI. In conclusion, the results suggest that free-breathing DWI has potential as an alternative to standard CE-MRI protocols in pediatric patients with known or suspected Crohn disease, without a substantial loss of diagnostic information and without the need for intravenous administration of contrast medium.

This thesis is written at the department of Business Studies at Uppsala University. The study addresses the differences in possibilities and difficulties of implementing business intelligence (BI)-systems among small IT-enterprises. BI-systems support enterprises in decision-making. To answer the aim of this thesis, theories regarding organizational factors determining a successful implementation of a BI-system were used. Theories regarding components of BI- systems, data warehouse (DW) and online analytical processing (OLAP) were also used. These components enable the decision-support provided by a BI-system. A qualitative study was performed, at four different IT-enterprises, to gather the empirical material. Interviews were performed with CEOs and additional employees at the enterprises. After the empirical material was gathered an analysis was performed to draw conclusion regarding the research topic. The study has concluded that there are differences in possibilities and difficulties of implementing BI-systems among small IT-enterprises. A difference among the enterprises is the perceived ability to finance an implementation. Another difference is in the managerial- and organizational support of an implementation, but also in the business need of using a BI- system in decision-making. There are also differences in how the enterprises use a DW. Not all enterprises benefits from the ability of a DW to manage complex and large amounts of data, neither from the advanced analysis performed by OLAP. The enterprises thus need to examine further if the use of a BI-system is beneficial and would be used successfully in their company.

Over the past two decades organizations have made considerable investment in implementing data warehousing and business intelligence to improve business performance through facts-based decision-making. Although many of these organizations reap the rewards of their investments, others find that realizing the full value proposition is elusive. While the literature is rich with studies regarding data warehousing and business intelligence, much of the existing research focused on the initial experiences of adoption and implementation, and few yielded empirical data that reflected post-implementation conditions that lead to mature capabilities and improved business performance. Sited at the Defense Intelligence Agency where data warehousing and business intelligence capabilities have been in place for 10 years, this study investigated the perceived influences of data warehousing and business intelligence maturity on organizational performance through the perceptions of end users and senior leaders. This study employed mixed methods to examine the linkages between organizational support, information technology capabilities, practices, use, and organizational performance. Using survey responses from end users (N = 29 respondents), the researcher employed linear regressions, and mediation analyses to test hypotheses and assess correlations among maturity variables and their effect on organizational performance. Conversely, the qualitative phase included semi-structured interviews with six senior leaders to understand their perceptions of existing data warehousing and business intelligence capabilities. The quantitative results and qualitative findings indicated significant correlations between the perceptions of organizational support, information technology capabilities, and use in predicting organizational performance. The discoveries resulting from this research represent an original contribution to the body of knowledge by providing empirical data to aid in advancing the scholarship and practice of the data warehousing and business intelligence maturity phenomenon.