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See detailThe Refugees and Article 56 of the 1971 Constitution
Al Hajjaji, Shams Al Din UL

Bachelor/master dissertation (2007)

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See detailGlobal and Local Gravity Field Recovery from Satellite-to-Satellite Tracking
Weigelt, Matthias UL

Doctoral thesis (2007)

The main objective of this thesis is the gravity field recovery using satellite-to-satellite tracking methods. Based on new technologies like the global positioning system and accelerometers satellite-to ... [more ▼]

The main objective of this thesis is the gravity field recovery using satellite-to-satellite tracking methods. Based on new technologies like the global positioning system and accelerometers satellite-to-satellite tracking yields a dramatic improvement in the de- termination of the Earth gravity field. Two dedicated satellite missions, namely the CHAllenging Minisatellite Payload (CHAMP) and the Gravity Recovery And Climate Experiment (GRACE) are underway. This work describes the processing of the satel- lite data from CHAMP and GRACE based on the energy balance approach. The first part discusses the global gravity field recovery from CHAMP. Specifically, it aims at a reprocessing of kinematic position data and at a refinement of the data processing strategies. Although the energy balance approach is theoretically simple, its imple- mentation proved to be quite challenging. By refining the processing techniques an improvement of up to 30\% is reached for the low degree spherical harmonic coefficients. Nevertheless, the solutions still depend strongly on the variability of the groundtrack. The quality of the monthly solutions can vary up to one order of magnitude. To ad- dress this challenge, an in-depth analysis gives new insight into the phenomenon, and a new and unique combination method with GRACE data is presented, which yields a more homogeneous set of solutions and reaches the edge of the recoverability of a time-variable gravity signal from high-low satellite-to-satellite tracking missions. In the second part the energy balance approach is applied to the GRACE mission. Pre- vious attempts of expressing the kinetic energy in terms of the K-band measurement make use of an approximation. In this work, an exact representation is introduced and is validated by simulations. In the third part, the aim is to make optimal usage of the data distribution in the high latitude area. For this, interpolation and downward continuation techniques are investigated and an improvement, compared to the global solutions, is achieved. Overall, the analysis provides new and valuable insight into the data processing of satellite-to-satellite tracking data using the energy balance approach. [less ▲]

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See detailAre there cross-cultural differences in empathy, self-esteem and distress disclosure?
Aleksic, Gabrijela UL

Bachelor/master dissertation (2007)

The purpose of this research was to find possible cross-cultural differences in empathy, self-esteem and distress disclosure involving 418 adolescents (217 females, 201 males) from four schools in the U.K ... [more ▼]

The purpose of this research was to find possible cross-cultural differences in empathy, self-esteem and distress disclosure involving 418 adolescents (217 females, 201 males) from four schools in the U.K., U.S.A., Serbia, and Luxembourg. Moreover, we wanted to know are there gender differences and is there an association between academic achievement and empathy, self-esteem, and distress disclosure. We used three scales: A Measure of Emotional Empathy for Adults and Adolescents (MEEAA) (Caruso & Mayer, 1998), The Distress Disclosure Index (DDI) (Kahn & Hessling, 2001), and Rosenberg’s Self-Esteem Scale (RSE) (Rosenberg, 1965). The scales appeared to be reliable (alphas ranging from .87 for the MEEAA, .86 for the RSE, and to .93 for DDI). The factor analysis showed that the RSE is bidimensional depicting Self-Worth and Self-Deprecation, the DDI is unidimensional as it supposed to be, and we chose three-dimensional solution for MEEAA depicting Empathic Suffering, Responsive Crying, and Positive Sharing. The MANOVA results showed that hypothesis on country differences in empathy, self-esteem, and distress disclosure is confirmed. There are significant country differences especially concerning the U.K. participants that reported the lowest tendency for empathy, self-esteem, and distress disclosure. Hypothesis that Serbian participants are the highest in reporting empathy was not confirmed. Moreover, hypothesis that American participants are the highest in reporting self-esteem was not confirmed either. Finally, hypothesis that the U.K. participants are the lowest in reporting distress disclosure was confirmed. Furthermore, hypotheses on gender differences were confirmed: females reported more of a tendency for empathy than males, males reported more of a tendency for self-esteem than females, and females reported more of a tendency to disclose distress than males. No association between academic achievement and empathy, self-esteem, and distress disclosure was found. Considering associations between empathy, self-esteem, and distress disclosure the results showed that there is a medium to strong association between empathy and distress disclosure in all countries, and a positive association between distress disclosure and self-esteem. Moreover, the results showed that there is a significant negative association between self-esteem and empathy, especially in the U.K. and Luxembourg. As well, cluster analysis grouped participants who are high in self-esteem, but low in empathy, and distress disclosure, in one group. We speculated that this general self-esteem might be “false” self-esteem or narcissism since narcissism is negatively correlated to empathy. [less ▲]

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See detailRelating to Nature: The Performative Spaces of Icelandic Tourism
Olafsdottir, Gunnthora UL

Doctoral thesis (2007)

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See detailZum Tragverhalten von Flachdecken mit integrierten hohlkastenförmigen Stahlprofilen
Schäfer, Markus UL

Doctoral thesis (2007)

Due to the demand for slim constructions and improvement of erection methods on building site composite slim-floor systems become more important. In the present european and national codes do not include ... [more ▼]

Due to the demand for slim constructions and improvement of erection methods on building site composite slim-floor systems become more important. In the present european and national codes do not include complete design rules for slim-floor constructions. Therefore the objective of this thesis is concentrated on the development of design rules for slim-floor girders. During the erection stage the elastic design resistance of the steel girder is decisive. Because of the slight plate thickness and sometimes considerable torsional stressing the influence of the shape deformation becomes more important and has to be considered. In this approach the steel sections are filled with concrete in the final state. Thereby the concrete in the openings, arranged in the web or upper flange, work concurrently as concrete dowels. The determination of moment resistance follows the rules for composite structures, respectively whereas in many cases the strain limited design is relevant and additionally the influences from transverse bending in the bottom flange have to be considered. Because of the sheathing of the concrete encasement by the steel section a hybrid truss model with a compression strut in the concrete section is developed, increasing the shear of the section. In case of fire, the directly flamed bottom flange can be substituted by longitudinal reinforcement bars and a high fire resistance period can be realized without any additional activities. For the analysis in case of fire, a design-method is extracted according to EN 1994-1-2. Based on a transient analysis, thermal analytic functions are developed to describe the temperature distribution in the cross section. The crack behaviour of the concrete slab has already a significant impact on the girder deformation in the serviceability limit state. The concrete flange adopts a remarkable part of the bending-moment. Compared to general treatment of common composite girders, the neglecting of these bending influences can lead to unrealistic camber of the girder. Therefore, an approximation procedure is derived that considers the bearing of the resilience of composite connector and the crack behaviour on the structure deformation. [less ▲]

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See detailUse of commercial simulation software for analyzing the dynamics of an injection-molding clamp unit
Hostert, Claude UL

Doctoral thesis (2006)

Today, the interest in integrated dynamic analysis of mechatronic systems increases. Different approaches are possible depending on the nature of the system, on the required complexity of the model, or ... [more ▼]

Today, the interest in integrated dynamic analysis of mechatronic systems increases. Different approaches are possible depending on the nature of the system, on the required complexity of the model, or simply on the tools available to the engineer. During this work, the aim was to implement specialized commercial simulation software packages and to combine them in order to simulate the dynamic behavior of mechatronic systems as for example an injection molding machine. The multi-body simulation software is the backbone of the current analysis as it inherently models large non-linear motions. It is possible to account for the flexibility of components in the MBS model if necessary. Furthermore, other simulation codes were used to model the hydraulic and controls systems. The case studies show the interest and the potential of a combined analysis of mechatronic systems. Once the different sub-models, generated with the adequate simulation tool, have been successfully linked and validated by measurements, various scenarios can be simulated and analyzed. The model provides the engineer with an additional insight into the overall system and thus with a better understanding of its dynamic characteristics. The interactions between the subsystems, which may be of very distinctive nature, can be investigated. Generally, it is difficult to predict such relations intuitively. Finally, the model allows to simulate with different design parameters and to asses the effect of modifications to these on the overall performance of the machine. This helps to identify the significant parameters that are crucial for an optimized functioning. [less ▲]

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See detailPeer‐to‐peer Mediation – Ein Unterrichtssubkonzept
Fischbach, Antoine UL

Bachelor/master dissertation (2006)

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See detailA Neural Reinforcement Learning Approach for Behavior Acquisition in Intelligent Autonomous Systems
Antonelo, Eric Aislan UL

Bachelor/master dissertation (2006)

In this work new artificial learning and innate control mechanisms are proposed for application in autonomous behavioral systems for mobile robots. An autonomous system (for mobile robots) existent in the ... [more ▼]

In this work new artificial learning and innate control mechanisms are proposed for application in autonomous behavioral systems for mobile robots. An autonomous system (for mobile robots) existent in the literature is enhanced with respect to its capacity of exploring the environment and avoiding risky configurations (that lead to collisions with obstacles even after learning). The particular autonomous system is based on modular hierarchical neural networks. Initially,the autonomous system does not have any knowledge suitable for exploring the environment (and capture targets œ foraging). After a period of learning,the system generates efficientobstacle avoid ance and target seeking behaviors. Two particular deficiencies of the forme rautonomous system (tendency to generate unsuitable cyclic trajectories and ineffectiveness in risky configurations) are discussed and the new learning and controltechniques (applied to the autonomous system) are verified through simulations. It is shown the effectiveness of the proposals: theautonomous system is able to detect unsuitable behaviors (cyclic trajectories) and decrease their probability of appearance in the future and the number of collisions in risky situations is significantly decreased. Experiments also consider maze environments (with targets distant from each other) and dynamic environments (with moving objects). [less ▲]

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See detailDie Rolle der Landwirtschaft in der Eigenständigen Regionalentwicklung der Region "West" Irlands
Sprenger, Birte UL

Doctoral thesis (2005)

Die Bedeutung der Landwirtschaft für die Eigenständige Regionalentwicklung unter Berücksichtigung der Multifunktionalität der landwirtschaft am Fallbeispiel der peripherem agrarstrukturell geprägten ... [more ▼]

Die Bedeutung der Landwirtschaft für die Eigenständige Regionalentwicklung unter Berücksichtigung der Multifunktionalität der landwirtschaft am Fallbeispiel der peripherem agrarstrukturell geprägten region West in der Republik Irland wird untersucht und bewertet. [less ▲]

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See detailFamily adjustment to disability and chronic illnessin children
Pit-Ten Cate, Ineke UL

Doctoral thesis (2004)

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See detailThe speech and language therapist’s role in differential diagnosis
Deroey, Katrien UL

Bachelor/master dissertation (2004)

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See detailNon-observabilité des communications interactives
Bernard, Nicolas UL

Bachelor/master dissertation (2004)

Ce stage a porté sur le problème consistant à rendre des communications interactives via l'Internet non-observables, afin d'apporter une intimité "forte" aux utilisateurs du réseau. En effet, bien qu'il ... [more ▼]

Ce stage a porté sur le problème consistant à rendre des communications interactives via l'Internet non-observables, afin d'apporter une intimité "forte" aux utilisateurs du réseau. En effet, bien qu'il existe un certain nombre de protocoles pour "sécuriser" les communications via l'Internet (par exemple SSL et IPsec), un certain nombre d'informations ne sont absolument pas dissimulées à un éventuel observateur. Ces protocoles ont pour but, en utilisant les techniques cryptographiques résumées dans la section précédente, d'une part de rendre inutilisables les informations transmises via le réseau pour ledit observateur en les lui rendant incompréhensibles, d'autre part d'identifier et d'authentifier un utilisateur de manière fiable, afin que des données confidentielles ne soient pas transmises à un attaquant se faisant passer pour quelqu'un d'autre. Par contre, dans ces protocoles "sécurisés", un observateur peut toujours déterminer quelles sont les parties qui communiquent, pendant combien de temps elles communiquent, et avoir une idée plus ou moins précise de la quantité de données échangées. Ces protocoles sont observables. Cela semble anodin, mais peut cependant avoir des répercussions d'ampleur non négligeable. Par exemple, prenons la consultation d'un site web statique (i.e. dont les pages ne changent pas et sont les mêmes pour chaque visiteur): Alice visite donc le site (statique) de Bob en utilisant le protocole https (c'est-à-dire le protocole du web "sécurisé" en le faisant passer dans SSL). Eve qui écoute le trafic sait qu'Alice consulte ce site, par contre elle ne peut voir quelles pages elle y consulte. Cependant, on peut imaginer qu'elle enregistre chaque requête (elle peut les distinguer par les pauses qui les séparent) et mesure la quantité de données échangées pour chacune. Ensuite, elle consulte elle-même le site de Bob et en télécharge (en utilisant également https) chaque page en procédant à des mesures similaires. En établissant des correspondances entre les deux jeux de mesures, elle a de bonnes chances de retracer le parcours d'Alice qui utilisait pourtant un protocole "sûr" pour consulter ce site! Nous avons étudié différentes possibilités pour rendre les communications non-observables et avons implémenté certaines d'entre-elles, en nous focalisant plus particulièrement sur des communications dont la durée est grande par rapport au temps d'établissement, et nécessitant une faible latence. [less ▲]

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See detailDie bakterielle Signalverarbeitung am Beispiel des Sucrose Phosphotransferasesystems in Escherichia coli : Modellierung und experimentelle Überprüfung
Sauter, Thomas UL

Doctoral thesis (2003)

Bacterial signal processing was investigated concerning the sucrose phosphotransferase system (sucrose PTS) in the bacterium Escherichia coli as an example. The about 20 different phosphotransferase ... [more ▼]

Bacterial signal processing was investigated concerning the sucrose phosphotransferase system (sucrose PTS) in the bacterium Escherichia coli as an example. The about 20 different phosphotransferase systems (PTSs) of the cell fulfil besides the transport of various carbohydrates, also the function of one signal processing system. Extra- and intracellular signals are converted within the PTS protein chain to important regulatory signals affecting e.g. carbon metabolism and chemotaxis. A detailed dynamical model of the sucrose PTS was developed describing transport and signal processing function. It was formulated using a detailed description of complex formation and phosphate transfer between the chain proteins. Model parameters were taken from literature or were identified with own experiments. Using a formal algorithm including cluster analysis, PTS and glycolysis could be identified as biological functional units with limited autonomy. Simulation studies together with experimental hints showed that the dynamic behaviour of phosphate transfer in the PTS runs within one second. Therefore a description of steady state characteristics is sufficient for describing the signaling properties of the sucrose PTS. A steady state characteristic field describes the degree of phosphorylation of the PTS protein EIIACrr as a function of the input variables extracellular sucrose concentration and intracellular PEP:pyruvate ratio. The model has been validated with different experiments performed in a CSTR using an sucrose positive Escherichia coli W3110 derivative. A method for determining intracellular metabolite concentrations has been developed. A sample preparation technique using a boiling ethanol buffer solution was successfully applied. The PTS output signal degree of phosphorylation of EIIACrr was also measured. Steady state conditions with varying dilution rate and dissolved oxygen concentration and dynamical variations applying different stimuli to the culture were considered. Pulse, and stop feeding experiments with limiting sucrose concentrations were performed. Simulation and experimental results matched well. The same holds for the expanded sucrose PTS and glycolysis model. [less ▲]

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See detailSécurisation de calculs pairs à pairs sur une grille de grappes
Varrette, Sébastien UL

Bachelor/master dissertation (2003)

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See detailDas modale Zeitgedächtnis
Klapproth, Florian UL

Doctoral thesis (2003)

Detailed reference viewed: 35 (2 UL)
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See detailHabilitation Thesis
Baraud, Yannick UL

Dissertation and these (2002)

Detailed reference viewed: 79 (8 UL)
See detailRichtungsmessung zu Satelliten
Weigelt, Matthias UL

Bachelor/master dissertation (2002)

Detailed reference viewed: 37 (0 UL)
See detailBenetzung in ternären Flüssigkeitsmischungen
Schilling, Tanja UL

Doctoral thesis (2001)

Detailed reference viewed: 66 (5 UL)
See detailLa discrimination des femmes au travail: le cas de la Commission européenne
Weis, Christiane UL

Bachelor/master dissertation (2001)

Detailed reference viewed: 69 (6 UL)
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See detailFacteurs associés à l’intégration stratégique des TIC par le personnel enseignant
Busana, Gilbert UL

Bachelor/master dissertation (2001)

Ce mémoire porte sur les facteurs qui incitent le personnel enseignant à faire une intégration stratégique des TIC1. Nous avons remarqué qu’une partie des enseignants et des enseignantes, en faible ... [more ▼]

Ce mémoire porte sur les facteurs qui incitent le personnel enseignant à faire une intégration stratégique des TIC1. Nous avons remarqué qu’une partie des enseignants et des enseignantes, en faible proportion, réussissent à faire une telle intégration, et qu’une partie n’en font pas. L’objectif de cette recherche est d’identifier les facteurs qui tendent à avoir une influence sur ce phénomène, ainsi que de saisir leur rôle et de comprendre comment ils opèrent. Dans une première partie, nous décrivons les possibilités des TIC et analysons pourquoi les technologies peuvent avoir un apport substantiel dans l’apprentissage des élèves. Or, nous constaterons par la suite qu’il y a une grande variabilité dans l’intégration des TIC chez le personnel enseignant, tant au niveau primaire qu’au secondaire. Comme nous aimerions comprendre le phénomène en profondeur, nous avons choisi une méthodologie de type qualitative. À l’aide d’entrevues semi-dirigées, nous relèverons les données nécessaires pour répondre à notre question de recherche. L’analyse par théorisation ancrée nous permet d’identifier les facteurs, leurs rôles respectifs et de comprendre comment ils opèrent. Nous constatons que les facteurs peuvent être classés en quatre catégories : Les connaissances et compétences du personnel enseignant, l’enseignant et l’enseignante comme personne, l’environnement de l’école et les facteurs “autres”. L’analyse fait ressortir tant les facteurs qui ont une influence positive que ceux qui tendent à inhiber l’intégration stratégique. Contrairement à ce que nous avons cru, les compétences techniques ne constituent pas le facteur le plus important, bien qu’il soit difficile, compte tenu du type de méthodologie employée, d’évaluer l’influence proportionnelle de chacun des facteurs. D’après les sujets interviewés, il semble que le facteur « gestion de classe » ressorte comme étant un peu plus important. Cette recherche se démarque du fait qu’elle traite des facteurs qui influencent l’intégration stratégique des TIC, un thème peu exploité dans le domaine des technologies en éducation. Nous croyons que les résultats de cette recherche permettront de faire avancer les connaissances dans ce domaine, et de donner des indices aux responsables en éducation qui veulent procéder à des changements pour faire avancer l’intégration stratégique des technologies. [less ▲]

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See detailLes algorithmes Minimax et Minimax(alpha,beta) : Application au jeu de Dames
Bernard, Nicolas UL

Dissertation and these (2001)

Detailed reference viewed: 115 (4 UL)
See detailMotologie zwischen objektiver und subjektiver Sinnesphysiologie
Wantz, Marc UL

Doctoral thesis (2000)

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See detailMaking Sense of Video Games: A textual Analysis of Tomb Raider II
Sunnen, Patrick UL

Bachelor/master dissertation (2000)

This dissertation is a textual analysis of the hard- profile computer game Tomb Raider II. After reviewing and discussing the literature related to computer games and associated action movies, I shall ... [more ▼]

This dissertation is a textual analysis of the hard- profile computer game Tomb Raider II. After reviewing and discussing the literature related to computer games and associated action movies, I shall outline Dowling's social activity theory and apply it exploratively to a range of computer game texts. I shall then apply the language of description more thoroughly to a sample of Tomb Raider II and a related walkthrough in order to analyse how they construct author and reader positions and to describe the nature and mechanisms of the distribution of practices between these positions. My work also includes an account of my personal engagement with the game. Finally, in my conclusion I shall give suggestions for further research. [less ▲]

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See detailRéalisation d'un Jeu de Dames en Objective Caml
Bernard, Nicolas UL

Dissertation and these (2000)

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See detailOverall mate attractiveness: Towards a Computational Metaphor of Human Mate Choice
Reuter, Robert UL

Dissertation and these (1999)

This paper provides a computational characterisation of human mate choice. In terms of evolutionary biology, choosing the "best" mating strategy is a matter of maximising the trade-offs resulting from the ... [more ▼]

This paper provides a computational characterisation of human mate choice. In terms of evolutionary biology, choosing the "best" mating strategy is a matter of maximising the trade-offs resulting from the costs and benefits associated with any activity "aiming" at survival and reproduction, like living to reproductive age, displaying desirable features, courting, mating, parenting, etc. Evolved mating strategies can descriptively be characterised as such cost/benefit analyses (or conditional strategies). They should take into account the effects of those biological, ecological, populational, social and cultural constraints that were recurrently affecting the long- term inclusive fitness of our hominid ancestors. Similarly, in terms of evolutionary cognitive science, choosing the "best" mate is a matter of maximising satisfaction of a set of positive and negative constraints affecting inclusive fitness. Overall mate attractiveness is conjectured to be the product of this dynamic multiple constraint satisfaction process. It is, moreover, shown that a computational metaphor based on parallel distributed processing captures essential features of human mate choice, like infatuation and the "beautiful-is-good" effect. It also provides an integrating view on the numerous preference factors documented to affect perceived mate value. Finally, the author proposes new empirical predictions about constraints on overall mate attractiveness to be explored in future multidisciplinary studies. [less ▲]

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See detailStaatliche Forschungsförderung der Sozialwissenschaften: Die Deutsche Forschungsgemeinschaft und die amerikanische National Science Foundation im Vergleich
Powell, Justin J W UL

Bachelor/master dissertation (1999)

Why have the social sciences been more successful at gaining funding from Germany's national science foundation, the Deutsche Forschungsgemeinschaft (DFG), than from the U.S. National Science Foundation ... [more ▼]

Why have the social sciences been more successful at gaining funding from Germany's national science foundation, the Deutsche Forschungsgemeinschaft (DFG), than from the U.S. National Science Foundation (NSF)? Historical-institutional case studies of the DFG's difficult reconstruction and NSF's complicated birth show how scientists negotiated postwar political conditions. Further, comparative analysis examines postwar research and development trends through 1997, including organization-level data on funding distributions between branches of science. Postwar consensus about the increasing importance of science enabled the rapid growth of government-sponsored research funds and distributing organizations, with the DFG and the NSF created to allocate basic research funds among and within disciplines. While institutionalized peer review systems balanced external political control and scientific freedom, competition between levels and branches of government and complex decision making processes affected federal research-sponsoring agencies' expansion as intermediary institutions. While both organizations attempt to shield themselves from political control by nonscientists, the NSF has been less successful than the DFG in maintaining its autonomy from federal policymakers. In Germany, the federal science ministry with its comprehensive budgeting process and constitutionally guaranteed academic freedoms strengthen the equilibrium of the science-politics nexus. In contrast, the US still lacks an executive branch department of science or technology and American social scientists only obtained a full-fledged social science directorate at the NSF in the 1990s. Comparative analysis shows significant differences in political decision-makers' control of these organizations, especially with respect to the natural sciences' dominance over the social sciences. German social scientists have maintained higher levels of government funding for basic research than their American peers, who suffered both lost autonomy and diminished funding, especially at NSF. [less ▲]

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See detailMetalmorphosis – Ou les délices inorganiques de quelques pierceurs à Rome
Reckinger, Rachel UL

Bachelor/master dissertation (1999)

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See detailDas Erstellen eines Programmes zum Lösen von mathematischen Sachaufgaben mit Hilfe der Pfeilsprache auf dem Computer (MSPC)
Busana, Gilbert UL

Bachelor/master dissertation (1999)

In dem vorliegenden Dokument werden die Voraussetzungen zur Erstellung eines Programmes zum Lösen von Mathematischen Sachaufgaben mit Hilfe der Pfeilsprache am Computer erläutert. Veröffentlichungen ... [more ▼]

In dem vorliegenden Dokument werden die Voraussetzungen zur Erstellung eines Programmes zum Lösen von Mathematischen Sachaufgaben mit Hilfe der Pfeilsprache am Computer erläutert. Veröffentlichungen von verschiedenen Autoren werden bezüglich des Aufbaus eines solchen Interfaces verglichen. Verschiedene Einflussfaktoren wie die geschlechtsspezifischen Unterschiede, Interaktionen zwischen Mensch und Maschine, der Erwerb mathematischer Kompetenzen, die Notwendigkeit von Feedback u.a. werden auf ihre Relevanz für den Entwurf eines solchen Programms untersucht. Aus den Schlussfolgerungen entstehen präzise Richtlinien (Vorschläge) an denen man sich bei der Programmation orientieren kann. Diese informatischen Richtlinien, und nicht die mathematischen, stehen im Mittelpunkt dieser Arbeit. Das Vergleichen der Aussagen der verschiedenen Autoren geschieht auf einer psychologisch-pädagogisch- und didaktischen Ebene, immer auf das logische Denkvermögen von 10- bis 12-jährigen Kindern bezogen. Im praktischen Teil wird ein Programm nach diesen Richtlinien erstellt und dessen Funktionsweise anhand einer Beispielaufgabe erläutert. Schließlich wird es mit einem ähnlichen Programm verglichen und kritisch beleuchtet, bevor mögliche Verbesserungsvorschläge aufgezählt werden. [less ▲]

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See detailAggregation Operators for Multicriteria Decision Aid
Marichal, Jean-Luc UL

Doctoral thesis (1998)

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See detailLes differénces liées au sexe dans les habiletés verbales et visuo-spatiales: Etude des effets de présentation intermodale
Reuter, Robert UL

Bachelor/master dissertation (1998)

The present study is based on predictions developed in the field of evolutionary psychology concerning the existence of sex differences in verbal and visuo-spatial abilities, namely in navigational ... [more ▼]

The present study is based on predictions developed in the field of evolutionary psychology concerning the existence of sex differences in verbal and visuo-spatial abilities, namely in navigational abilities (MARTIN 1998), in mastery of water-level horizontality (ROBERT 1990), geographic knowledge, spatial memory (EALS & SILVERMAN 1994) and verbal fluencies. We investigated the potential influence of verbal processes on the processing of visuo-spatial information. Cross-modality conditions were thus used, which required verbal processing of visuo-spatial inputs at different levels. The significant results obtained all show a male advantage: in spatial navigation, in mastery of water-level horizontality, in geographic knowledge (names of countries), but also in spatial location memory, as well as in a verbal fluencies task (animal condition), although no such advantages were expected here. No female advantage was found, not even for the "female" task. This clearly restricts the conclusions that could be drawn from our study. Overall, the performances in tasks requiring verbal encoding of spatial information are very similar to those in classical (spatial) conditions, or they are not directly linked to language processing. Thus no clear-cut conclusions can be made about the intervention of verbal processes in navigational behaviour or spatial memory. The verbal fluency task on names of countries yielded a male advantage suggesting a male superiority in rapidly accessing information represented - in a visuo-spatial format - in long-term memory. This result clearly contrasts with Halpern et al.’s (1996) process-oriented model of cognitive sex differences. On the other hand, the spatial precision of geographic representations in males are rather low, as is suggested by the results in a task about relative positions of countries of the American continent. It seems that the quality of spatial discourse depends more on the quality of spatial representations than on verbal abilities. [less ▲]

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See detailPolitische Partizipation von Frauen in Luxemburg seit 1919
Wagener, Renée UL

Bachelor/master dissertation (1998)

Detailed reference viewed: 80 (8 UL)
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See detailDiscrete element analysis of granular materials
Van Baars, Stefan UL

Doctoral thesis (1996)

Discrete Element Analysis of Granular Materials During oil and gas production, several years after drilling a borehole, sand particles and small sandstone particles start to break away from the borehole ... [more ▼]

Discrete Element Analysis of Granular Materials During oil and gas production, several years after drilling a borehole, sand particles and small sandstone particles start to break away from the borehole surface. These particles can damage the transport pipes and other equipment in a short period of time. By simulating this borehole behaviour with the thick-walled cylinder test, four phenomena were found which cannot be explained by conventional continuum mechanics: 1. Despite the compressive stress, failure occurs on the micro level due to tension cracks. 2. These cracks are not diagonal to, but parallel to, the borehole surface. 3. These cracks cause two diametrically opposite breakouts. 4. The functional failure of the borehole starts at a higher radial pressure than predicted. In 1979, Cundall developed a computer model, based on the basic elements of granular materials, i.e. the grains themselves and their interactions, to describe the behaviour of these materials. Lindhout tried, in 1992, to use this model to describe the cylinder test. Due to compaction problems, stability problems and the large computational time, this could not be achieved. Therefore a new model was developed by the author, which does not use the equations of motion, but the equations of equilibrium, to calculate the new grain positions. This model can be used both for non-cohesive grains (sand) and for cohesive grains (sandstone). The results can generally be described by an advanced Mohr-Coulomb model. However, there are a few exceptions. Firstly, during loading of a granular structure, many contacts between the grains will collapse, not due to shear deformation as Coulomb suggests, but due to tension failure. Secondly, these micro cracks always occur in the direction of the major principal stress, which might be another direction than the observed failure surface. In this way, the axial micro cracks form a diagonal failure surface during a biaxial test, but the axial micro cracks in a cylinder test may form a failure surface parallel to the borehole surface. During the formation of natural sandstone, the difference between the horizontal and vertical stress causes anisotropy in the strength behaviour of this material. This or other anisotropies may explain the diametrically opposite breakouts. The conclusion that a borehole fails at a higher radial pressure than predicted, originates from the definition difference between local failure and functional failure and the large rest capacity of a thick-walled cylinder. [less ▲]

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See detailRhoticity and related sound changes in British English from 1700 to the present day
Deroey, Katrien UL

Bachelor/master dissertation (1995)

Detailed reference viewed: 49 (2 UL)
See detailDéchiffrer Borges : le thème des mathématiques dans les contes, essais et poèmes
de Saint-Georges, Ingrid UL

Bachelor/master dissertation (1995)

Detailed reference viewed: 71 (3 UL)
See detailThe gerund and the infinitive: A contrastive study of their functions within the sentence
Deroey, Katrien UL

Bachelor/master dissertation (1994)

Detailed reference viewed: 68 (3 UL)
See detailSequenz und Sequenz-Struktur Vergleiche und deren Anwendung für die Struktur- und Funktionsvorhersage von Proteinen
Schneider, Reinhard UL

Doctoral thesis (1994)

Zusammenfassung der Inaugural-Dissertation Name: Reinhard Schneider Titel: Sequenz und Sequenz-Struktur Vergleiche und deren Anwendung für die Struktur- und Funktionsvorhersage von Proteinen Betreuer ... [more ▼]

Zusammenfassung der Inaugural-Dissertation Name: Reinhard Schneider Titel: Sequenz und Sequenz-Struktur Vergleiche und deren Anwendung für die Struktur- und Funktionsvorhersage von Proteinen Betreuer: Prof. Dr. K. C. Holmes (MPI für medizinische Forschung, Heidelberg) Durch die sogenannten Genomprojekte wird es in den nächsten Jahren zu einer enormen Vergrößerung der biologischen Sequenzdatenbanken kommen. Eine unabdingbare Voraussetzung zur Nutzung dieses Rohmaterials stellt dabei die Analyse dieser Sequenzdaten mit Hilfe rechnergestützter Methoden dar. Eines der Hauptanwendungsgebiete von Rechnern für die Funktions- und Strukturvorhersage von Proteinen werden dabei selektive Datenbanksuche nach biologisch signifikanten Ähnlichkeiten sein. Zur Signifikanzabschätzung eines Proteinsequenzvergleiches (Alignment) wurde ein empirisch abgeleiteter Homologieschwellenwert definiert. Wichtigstes Merkmal ist dabei eine starke Abhängigkeit von der Länge des betreffenden Alignments. Diese Signifikanzabschätzung ermöglicht sowohl den Ausschluß von nicht verwandten Proteinen, wie auch die Detektion von schwachen Sequenzverwandtschaften. Aufgrund der Allgemeingültigkeit des Homologieschwellenwertes kann er als einfacher und effizienter zusätzlicher Filter für andere Methoden, wie z.B. schnelle Datenbanksuchen, verwendet werden. Es wurde ein neuer Algorithmus für den multiplen Sequenzvergleich entwickelt, der eine relativ geringe rechnerische Komplexität besitzt. Das Hauptmerkmal dieses Algorithmus besteht in der Ableitung von sogenannten positionsabhängigen Konservierungsgewichten, die als zusätzliche Parameter im dynamischen Programmieralgorithmus verwendet werden und zu einer deutlich gesteigerten Sensitivität bei Datenbanksuchen führt. Die programmiertechnische Auslegung des Algorithmus erlaubt die zukünftige Erweiterung auf den Vergleich einer Sequenz gegen ein Sequenzprofil bzw. den Vergleich zweier Sequenzprofile. Um auch zukünftig sensitive Datenbanksuchen in einer vertretbaren Rechenzeit durchführen zu können,, wurde das Programm auf parallele Rechner portiert. Die Ergebnisse zeigen, daß mit den heute verfügbaren massiv parallelen Rechnern ein beinahe interaktives Arbeiten möglich ist. Aufbauend auf dieser Arbeit wird derzeit im Rahmen eines europäischen Projektes die Implementierung der Profilmethoden auf Parallelrechner der neuesten Generation durchgeführt und der Nutzen für das industrielle “Protein design” bestimmt. Mit Hilfe des Homologieschwellenwertes konnte eine Datenbank für homologie-abgeleitete Proteinstrukturen (HSSP) entwickelt werden. Diese Datenbank wird der Öffentlichkeit auf verschiedenen Wegen zugänglich gemacht und hat sich als ein gewisser Standard etabliert. Die Datenbank findet dabei Verwendung im automatisierten dreidimensionalen Modellbau von Proteinstrukturen, sowie als Hilfsmittel und Datengrundlage für ein weitgestecktes Feld von statistischen und anderen theoretischen Arbeiten. Die Verwendung der Datenbank hat einen entscheidenden Beitrag bei der Entwicklung des derzeit besten Programms zur Vorhersage der Sekundärstruktur von Proteinen geleistet. Diese Vorhersagemethode basiert auf einem neuronalen Netzwerk, das die Informationen eines multiplen Sequenzvergleichs ausnutzt. Zur Berechnung der multiplen Sequenzalignments und der dazu notwendigen Datenbanksuche wird das in dieser Arbeit entwickelte Programm verwendet. Die Methode wurde in Form eines Vorhersagedienstes, der über internationale Datenleitungen verfügbar ist, der Öffentlichkeit zugänglich gemacht. Einen neuen Ansatz für die Vorhersage von Proteinstruktur bei fehlender Sequenzverwandtschaft zu einer bereits bekannten Struktur stellt die Methode für das Sequenz-Strukturalignment (“threading”) dar. Dazu wird eine dreidimensionale Struktur in Form von interatomaren Kontakten beschrieben und mit Hilfe von Präferenzparametern die Tauglichkeit einer Sequenz in eine Struktur bewertet. Die Ergebnisse zeigen, daß sowohl eine Verbesserung der abstrahierten Beschreibung für eine dreidimensionale Proteinstruktur, wie auch ein verbesserter Alignmentalgorithmus notwendig ist. Ein in der Praxis vielversprechender Ansatz ist die Verwendung von Methoden, die einerseits eine abstrahierte 3D-Beschreibung zulassen und zusätzlich einen gewissen Grad an Sequenzinformation, etwa in Form eines Sequenzprofils mit einbeziehen. Am Beispiel eines kompletten Chromosoms aus Hefe wurde eine komplexe funktionelle Genomanalyse durchgeführt. Hierbei konnten eine Reihe von biologisch interessanten Sequenzverwandtschaften aufgedeckt werden, waren jedoch mit einem hohen Arbeitsaufwand verbunden. Dabei stellte sich die ungenügende Integration der vorhanden Methoden und heterogenen Datenbanken als Hauptproblem heraus. Die dabei gesammelten Erfahrungen fließen derzeit in die Entwicklung eines integrierten Softwarepackets ein, mit dessen Hilfe es möglich sein wird, den Arbeitsaufwand, der zur Analyse von großen Datenmengen notwendig ist, drastisch zu reduzieren. [less ▲]

Detailed reference viewed: 145 (2 UL)
Full Text
See detailLe fait du prince étranger
Kinsch, Patrick UL

Doctoral thesis (1994)

Detailed reference viewed: 127 (12 UL)
See detailMainstreaming, Social Reproduction, and the Continuing Search for Integration
Powell, Justin J W UL

Bachelor/master dissertation (1992)

Detailed reference viewed: 83 (15 UL)
Full Text
See detailCaractérisation de méthodes de rangement basées sur des relations binaires valuées
Marichal, Jean-Luc UL

Bachelor/master dissertation (1992)

Detailed reference viewed: 95 (14 UL)
See detailEmotionale Verarbeitung von Arbeitslosigkeit
Limbach-Reich, Arthur UL

Bachelor/master dissertation (1992)

Detailed reference viewed: 44 (0 UL)
See detailModelle der dreimodalen Faktorenanalyse
Krolak-Schwerdt, Sabine UL

Doctoral thesis (1991)

Detailed reference viewed: 24 (1 UL)
See detailEast-West Migration and Unification Policy in Germany, 1945–1990
Powell, Justin J W UL

Bachelor/master dissertation (1990)

Detailed reference viewed: 73 (9 UL)
See detailEvaluation und Meta-Evaluation in Sozialarbeit und Sozialpädagogik
Limbach-Reich, Arthur UL

Bachelor/master dissertation (1990)

Detailed reference viewed: 45 (3 UL)
See detailAudiovisuelle Bestandsaufnahme des Sprachunterrichts für Ausländerkinder
Wantz, Marc UL

Bachelor/master dissertation (1989)

Detailed reference viewed: 30 (0 UL)
See detailUntersuchungen zum luxemburgischen Volkslied
Sagrillo, Damien UL

Bachelor/master dissertation (1989)

Detailed reference viewed: 61 (5 UL)
See detailLes œuvres d’art temporelles de Voth - Les coordonnées de Hannsjörg Voth entre l’art du passé et les expressions plastiques contemporaines
Dell, Paul UL

Dissertation and these (1987)

Hannsjörg Voth produces with the evident necessity of high physical endurance art projects with mythical and utopian contents. The creations of the artist touch so many artistic domains that it is not ... [more ▼]

Hannsjörg Voth produces with the evident necessity of high physical endurance art projects with mythical and utopian contents. The creations of the artist touch so many artistic domains that it is not possible to attach him to a single typology of art expression. The present research features an analyze and an interpretation of Voths’ artwork in the setting of his personal artistic evolution. In his creative approach, the methodical progress to accomplish what is called in this research an art project, is studied in all its sequences in order to define in a more clear way this new artistic expression. It tries not only to overcome the traditional supports but also includes modern medias, so as photos and videos as integral and essential parts of the artists’ works. A confrontation with the art of the past and simultaneously contemporary creative expressions allows to better define the art coordinates of Voth and to give an evaluation of originality and artistic quality in the context of countless aesthetic forms that represent visual arts at the end of the XXth century. [less ▲]

Detailed reference viewed: 108 (13 UL)
See detailEin neues graphentheoretisches Modell für die dreimodale Faktorenanalyse
Krolak-Schwerdt, Sabine UL

Bachelor/master dissertation (1986)

Detailed reference viewed: 36 (2 UL)
See detailSprachpolitik in Katalonien
Ehrhart, Sabine UL

Bachelor/master dissertation (1985)

Detailed reference viewed: 82 (1 UL)
See detailRéminiscences des maîtres anciens et éléments modernes dans le réalisme de Claudio Bravo
Dell, Paul UL

Bachelor/master dissertation (1984)

At the beginning of his career, Claudio Bravo became known as a portraitist of the jet set people. Yet, to reduce him on these activities would not do justice to him. In fact, he was a neo-realistic ... [more ▼]

At the beginning of his career, Claudio Bravo became known as a portraitist of the jet set people. Yet, to reduce him on these activities would not do justice to him. In fact, he was a neo-realistic painter with many facets. His trompe-l’oeil paintings showed that Bravo was fascinated by form and texture of the represented characters or objects. The artist tried in same way to give the signs of reality a metaphysical presence: Conceptually significance should go beyond their outward appearance. Just as his technique, his paintings become statements of perfection. Compared to his contemporary mainstream fellows, his approach was somehow an anachronism. He borrowed iconographic content or image composition from famous artist of the past such as Rafael, Caravaggio, Velasquez, Titian or Manet, in order to transform the appropriations with his hyper-realistic technique into a modern version, stating a touch of timelessness, due to the sobriety of the decoration and time neutral garment of the protagonists. He had also formal affinities to photo- or hyper-realistic US-painters of the 1960s such as Estes, Close and Goings or even the American illustrator Rockwell. His package wrapped subject paintings were obviously inspired by the smaller cloth enveloped and tied up objects of an early Christo. Pop artists gave also inspiration with their representation of banal consumer objects. However, Bravo did not share the message of the pop artists, who were critical time spirit oriented reporters of popular consuming routines in a society that was switching more and more to futility and sometimes vulgar communication. This lack of a deeper message, going beyond celebrating the aesthetics of super-realistic representation, was pointed out by many art critics, committed to a more contemporary view on art. When Bravo painted a pop icon like a Coca-Cola bottle or a moto-sport helmet, his inherent interest focused on the fidelity to the outward appearance and conceptually on a metaphysical sublimation of its mere physical presence. The research deals with the above mentioned questions and discusses whether the approach of Bravo was simple epigonism or an authentic renewal of realistic painting. [less ▲]

Detailed reference viewed: 119 (14 UL)