This essay argues that repression and defense mechanisms contribute to the unreliability of Stevens’ narrationthrough three aspects: Stevens’ uncertainty of certain memories, his failure to report certain scenescorrectly and his defensive, self-contradictory discourse. There is no single best way to define what is consideredreliable and what is unreliable in narratology because the complexity of fictional characters will renderdifferent kinds of unreliability. This essay detects three kinds of unreliability of Stevens corresponding to thethree aspects mentIoned above: the first kind results from the untrustworthiness of our memory, the secondkind is the contradiction between the voice of the narrator and the other characters and the third kind lieswithin the narrative discourse. The unreliability of Stevens’ narration attributes to repression and defensemechanisms. The five kinds of defense mechanisms analyzed in the essay are selective memory, denial,projection, reaction formation and rationalization. In order to defend his self-image as a great butler, Stevenslies to or hides from himself and tries to avoid acknowledging certain undesirable thoughts or emotions. Eventhough Stevens becomes more reliable as he gains more self-realization during the road trip, his defensesare still on.

Le constat selon lequel le droit au juge au profit des personnes physiques et morales est un élément de l’État de droit, et donc de l’Union de droit, constitue le point de départ de l’étude du droit au juge dans l’Union européenne. Sur le plan de l’effectivité de la protection juridictionnelle des droits que les particuliers tirent de l’ordre juridique de l’Union, on ne peut que constater que celle-ci est profondément conditionnée par les voies de droit ouvertes aux individus dans les ordres juridiques nationaux.L’examen du droit au juge devant les juridictions nationales démontre que l’ordre juridique de l’Union a réussi à leur imposer les prémisses d’un véritable droit processuel de l’Union. Concernant la capacité des juridictions de l’Union à assurer le droit au juge des particuliers, il est permis de soutenir que les limitations originaires de ce dernier ont, en partie, été comblées par l’entrée en vigueur du Traité de Lisbonne, qui a réduit le déficit juridictionnel dans le cadre de l’Union par la mise en place d’une juridictionnalisation accrue, une meilleure accessibilité à certaines voies de recours et l’inscription de garanties complémentaires, notamment en ce qui concerne le respect du droit à un procès équitable. Le postulat selon lequel l’Union européenne dispose d’un système complet et effectif de protection des droits des particuliers, s’il n’est pas exempt de critiques, tend néanmoins à se confirmer.Telle est l’ambition de cette recherche qui s’ordonne selon une structure bipartite : la protection juridictionnelle devant les juridictions nationales ; la protection juridictionnelle devant les juridictions de l’Union européenne. / The finding that the right to an effective judicial protection for the benefit of natural and legal persons is an element of the rule of law, and thus the Union of law, is the starting point of the study to the effective judicial protection in the European Union. In terms of effectiveness of the judicial protection of rights, which individuals derive from the legal order of the Union, it has been established that this latter is deeply conditioned by the remedies offered to individuals in the national legal systems. The review of judicial protection before the national courts demonstrates that the legal order of the European Union has managed to impose national courts the beginnings of a real procedural law of the Union. Concerning the ability of the European Union courts to ensure the right to an effective judicial protection of individuals, it is permitted to argue that the original limitations to the judicial protection have, in part, been addressed by the entry into force of the Lisbon Treaty, which reduced the judicial deficit through the Union by the extension of the jurisdiction of the courts, the improvement of the accessibility to certain remedies before the courts of the Union and the inclusion of additional safeguards, especially concerning the right to a fair trial. The assumption that the European Union has a complete and effective system of judicial protection of individual rights, which is not always free from criticisms, nevertheless, tends to confirm. This is the ambition of this research, which is organized in a bipartite structure: the judicial protection before the national courts ; the judicial protection before the courts of the European Union.

This thesis deals with the Syrian conflict. The Syrian conflict has continued for over three years (April 2014) and still constitutes a topical and developing affair. It represents a pressing and unresolved national and international issue. There is a vast amount of groups with different ideas involved in this conflict. During the conflict, conventional, as well as chemical weapons were used. The consequences of the fighting are mostly faced by local inhabitants who have been severely suffering due to the harsh living and humanitarian conditions. The aim of this thesis is to depict the problems of the Syrian conflict, evaluate the role the UN has had up to the present, and answer the question whether the UN has totally failed in solving the Syrian conflict, or not.

Over the last years, bicycles have been addressed in newly developed driver assistance systems for passenger cars on a voluntary basis, and beginning with the blind spot assist systems, this tendency has been picked up by vehicle regulations and systems are made mandatory. This paper intends to give a detailed summary of which vehicle regulations are currently addressing bicycles, when they come into force and if they will be mandatory in the EU. Also, the performance of already available active safety systems for bicycles (not covered by regulatory requirements) and their technological potential will be included.

Problématique : Les adultes ayant des troubles neurologiques doivent composer avec moins de possibilités de participation sociale et lutter contre l’isolement. Mis ensemble, ces éléments contribuent au défi que constitue l’intégration communautaire chez ces populations. L’atteinte d’un niveau d’intégration communautaire satisfaisant aux yeux de ces individus est souvent décrite comme l’ultime finalité en réadaptation. Or, ce niveau d’intégration communautaire est rarement atteint, ce qui suggère que les interventions en réadaptation connaissent des limites à ce niveau. Afin de favoriser l’intégration communautaire des personnes ayant des troubles mentaux, plusieurs approches en réadaptation psychosociale intègrent une perspective centrée sur les forces (PCF). L’approche centrée sur les forces (ACF) est la plus robuste au niveau scientifique et fait souvent office d’exemple dans le domaine. Or, il n’y a pas de PCF formalisée ou formellement implantée en réadaptation physique. Toutefois, cela ne veut pas dire que certains principes d’intervention qui sont propres à une PCF ne sont pas perçus ou vécus en réadaptation physique. La présence de tels principes en réadaptation physique pourrait entre autres s’expliquer par le virage proposé à l’intérieur des lignes directrices régissant la pratique de l’ergothérapie au Canada. Objectifs : (1) Synthétiser l’état des connaissances quant aux objets d’interventions soutenant l’intégration communautaire dans un champ spécifique, soit celui de l’ergothérapie auprès de clientèles adultes aux prises avec des troubles neurologiques (article 1). (2) Vérifier si le Community Integration Questionnaire mesure bien un des effets attendus des PCF, plus précisément l’intégration communautaire, par le biais d’un examen des connaissances concernant ses qualités métrologiques (article 2). (3) Dépeindre les perceptions des objets d’interventions s’inscrivant dans une PCF, plus particulièrement celles qui touchent les forces de l’individu, du point de vue d’adultes aux prises avec des troubles neurologiques dans un contexte de services externes de réadaptation. Le recours à l’expérience de personnes iii composant avec une sclérose en plaques et une blessure médullaire permettra de considérer différents contextes et services de réadaptation, puisque les caractéristiques de la mise en œuvre de services de réadaptation pour ces deux clientèles sont très contrastées (article 3). Méthodes : Trois études ont été réalisées : (1) un examen de la portée dans cinq bases de données scientifiques ; (2) une revue systématique dans cinq bases de données scientifiques ; et (3) une étude de cas exploratoire auprès deux clientèles aux prises avec des troubles neurologiques (sclérose en plaques et blessure médullaire). Résultats : (1) L’examen des 47 écrits retenus démontre que les interventions ergothérapiques porteuses en matière d’intégration communautaire doivent être centrées sur l’occupation, viser l’atteinte de buts autodéterminés et être réalisées à même la communauté. Aucun des écrits retenus ne présentait de façon explicite une pratique centrée sur l’habilitation ; (2) L’analyse de dix études réalisées auprès de plus de 3000 individus sur les qualités métrologiques du Community Integration Questionnaire (CIQ) démontre un niveau preuve embryonnaire quant à une utilisation sécuritaire du CIQ pour mesurer l’IC (un des effets attendus d’une PCF) auprès de populations autres que celles vivant avec les séquelles d’un traumatisme crânien ; (3) Aux yeux des participants interviewés, les relations thérapeutiques supportent bien l’espoir et l’autodétermination. Les forces individuelles semblent toutefois peu mobilisées dans les processus de réadaptation physique auprès des clientèles à l’étude, ce qui limite l’atteinte d’un niveau satisfaisant d’intégration communautaire. Conclusion : Les pistes d’interventions probantes énoncées doivent guider les pratiques et la recherche en ergothérapie en matière d’intégration communautaire et davantage de place doit être faite à l’habilitation. Une perspective axée sur les forces comprend des composantes communautaires ou collectives ; tant sur le plan d’objets d’intervention, que sur le plan des finalités attendues. Les forces de l’individu ayant été mises en évidence dans le cadre de cette thèse, les forces environnementales devront être documentées afin de iv dresser un portrait initial plus complet de l’intégration d’une perspective axée sur les forces en réadaptation auprès des clientèles présentant des troubles neurologiques. / Rationale: Adults living with a neurological disorder must negotiate with fewer opportunities for social participation and fight isolation. Taken together, these elements contribute to the challenge of community integration for these populations. Reaching a satisfactory level of community integration is often described as the ultimate goal in rehabilitation. However, this goal is rarely achieved, which suggests that interventions know limits at this level. Several approaches to psychosocial rehabilitation incorporate this concern for community integration and a strengths-based perspective (SBP). The strengths model of case management (SM) is an evidence-based approach that often serves as an example in the field. However, there is no formalized or formally implemented strengths-based perspective in physical rehabilitation. However, this does not mean that some interventions or principles that are specific to such perspectives are not perceived or experienced in physical rehabilitation. The presence of strengths-based perspective in physical rehabilitation could be explained, among other things, by the proposed shift in occupational therapy practice guidelines in Canada. Objectives: (1) Synthesize the state of knowledge regarding the objects of interventions supporting community integration in a specific field, that is, occupational therapy for adults with neurological disorders (article 1). (2) Verify that the Community Integration Questionnaire (CIQ) measures community integration, through a systematic review of its metrological qualities (article 2). (3) Depict the perceptions of the objects of interventions within a SBP, regarding the mobilization of individual’s strengths, from the perspective of adults with neurological disorders in the context of outpatient rehabilitation services. Experience of people with multiple sclerosis and spinal cord injury will make it possible to consider different contexts and rehabilitation services, since the characteristics of the implementation of rehabilitation services for these two clienteles are very different (section 3). vi Methods: Three studies were conducted: (1) a scoping review in five scientific databases; (2) a systematic review in five scientific databases; and (3) an exploratory case study with two clienteles with neurological disorders (multiple sclerosis and spinal cord injury). Results: (1) Data from 47 articles demonstrate that supportive occupational therapy interventions for community integration must be occupation-based, selfdetermined, and community-based. None of the selected literature explicitly presented a practice focused on enablement; (2) Data from ten studies conducted with more than 3000 individuals on the metrological qualities of the Community Integration Questionnaire (CIQ) demonstrate an embryonic level of evidence for the safe use of CIQ to measure CI (one of the expected effects of a SBP) with populations other than those living with the aftermaths of traumatic brain injury; (3) Therapeutic relationships support hope and self-determination. However, individual strengths appear to be little involved in physical rehabilitation processes with the clientele in question, which limits the achievement of a satisfactory level of community integration. Conclusion: Outlined scientific evidences must guide occupational therapy practices and research in community integration and more research should be made concerning enablement. SBP includes community or collective components; both in terms of objects and effects of intervention. Environmental strengths will need to be documented in order to provide a more complete initial picture of SBP in the rehabilitation of people living with neurological condition.

Non-UN peace operations are becoming an increasingly important conflict mitigating tool. Whilst many studies find these operations unable to mitigate conflict and promote peace, the explanations for these findings mainly focus on material aspects like mission size and peacekeepers’ capability. In order to better understand the discrepancies between UN and non-UN peace operations’ success, this thesis argues that UN operations might be more efficient due to higher perceived legitimacy. In order to analyze whether the superior legitimacy of the UN explains their higher ability to mitigate conflict, this study analyzes whether non- UN peace operations authorized by the UN are more able to mitigate conflict than non-authorized peace operations. The argument is tested by applying an OLS regression to a data frame including all intrastate conflicts between 1993 and 2016 to study the covariation between conflict intensity and the presence of UN authorized and non-authorized peace operations. The results do not support the hypothesis that UN authorization increases non-UN peace operations’ conflict mitigating abilities. This suggests that material factors might better explain peace operations’ success or that UN authorization does not substantially increase the perceived legitimacy of non-UN peace operations.

United Nations peacekeeping forces and operations, have long had a history of crimes against civilians by its personnel, not least concerning crimes of sexual exploitation and abuse. While human rights violations are grave despite their origin, there is a specific element of impunity and distrust when the same people who comes to ‘protect’, are the same people who become perpetrators. In this sense, it is notably interesting and important to examine victims’ rights to access justice when crimes have been committed by UN Personnel. The primary aim is to explore to what extent the fore-mentioned victims have the possibility to access justice within the legal system of UN Transitional Administrations. These UN operations are chosen since it is particularly important to examine the extent to which victim’s may access justice when the UN exercises governmental powers and acts as a quasi-state. An underlying aim is to explore how the eventual inconsistencies within this system may be colored by postcolonial tendencies. In this sense, the study is conducted through a doctrinal method with a postcolonial perspective, examining the normative aspects of law in the light of a critical lens. The legal basis and the legal obligations of UN Transitional Administrations are compared to the International Standard on Victims’ rights and evidence on how victims’ rights to access justice is practiced within these administrations. Finally, the aim is to evaluate the result of this analysis from the standpoint of postcolonial theory.

Diese Dissertation beschreibt die Messung des Wirkungquerschnitts für die Produktion von ttbb in Protonkollisionen mit einer Schwerpunktsenergie von √s = 8 TeV. Der verwendete Datensatz entspricht einer integrierten Luminosität von 20.3/fb. Der Wirkungsquerschnitt wurde aus der Anzahl der Signalereignisse bestimmt, die durch harte Schnitte insbesondere auf genau 4 identifizierten b-jets, selektiert wurden, was zu einer hohen Reinheit des Signals führt. Bei der Messung wurden die präzisesten Kalibrierungen von der Jet-Energieskala und der b-jet Effizienz benutzt. Die Messung wurde in einem Referenzphasenraum durchgeführt, der daraufhin optimiert wurde, die Abhängigkeit von der Modellierung zu minimisieren. Der gemessene Wirkungsquerschnitt beträgt 18.9 ± 3.5 (stat)+5.6 (sys) ± 0.6 (Lumi) fb oder, nachdem der Beitrag von ttH(bb) und ttZ(bb) abgezogen wurde: 17.8 ± 3.5 (stat)+5.9 (sys) ± 0.6 (Lumi) fb. Das Ergebnis wurde mit einer Vielzahl von theoretischen Vorhersagen verglichen, einschließlich NLO-Berechnungen mit Partonschauern und einer Reihe von Modellen die sich in der Beschreibung der Gluon Spaltung unterscheiden. Es wurde gezeigt, dass das exstremste Model den Wirkungsquerschnitt überschätzt und dass die Messung die Vorhersagen bevorzugt, die mit einer niedrigen Renormierungs- und Faktorisierungsskala, berechnet wurden. / This thesis presents the measurement of the ttbb production cross-section, using a dataset of 20.3/fb of pp collisions collected with the ATLAS detector at 8 TeV. The measurement is based on a cut-and-count method, using a sample of events with exactly four b-tagged jets, which is shown to have a high purity in signal events. The measurement exploits the most precise jet energy scale and b-tagging calibrations and is performed in a fiducial phase space that is designed to minimize the model dependence of the measurement. The fiducial cross-section is measured to be 18.9 ± 3.5 (stat)+5.6 (sys) ± 0.6 (Lumi) fb or subtracting the contribution from ttH(bb) and ttZ(bb) final states, 17.8 ± 3.5 (stat)+5.9 (sys) ± 0.6 (Lumi) fb. The result is compared with a multitude of theoretical predictions, including different NLO calculations matched to a parton shower, which constitute the most precise predictions available to date, as well as with a series of models that differ in the description of the gluon splitting to b-quarks. It is shown that the most extreme gluon splitting model overestimates the observed rate of ttbb production and that the measurement favors calculations performed with renormalization/factorization scales which are softer than the scales usually employed in similar calculations.

Das HERA-$B$-Experiment am Deutschen Elektronen-Synchrotron (DESY) in Hamburg dient der Untersuchung der Physik von Teilchen, die $b$-Quarks enthalten. Der Schwerpunkt des Ex\-pe\-ri\-mentes liegt auf der Messung der CP-Verletzung im System der neutralen $B$-Mesonen. Es wird erwartet, dass die pr\"azise Bestimmung der CP-Asymmetrie im Zerfallskanal $B^0(\bar{B}^0)\to J/\psi K_S^0$ gro{\ss}en Einfluss auf die Weiterentwicklung des Standardmodells der Elementarteilchenphysik und g\"angiger kosmologischer Theorien haben wird. Das HERA-$B$-Experiment nutzt den Protonenstrahl des HERA-Ringes, um in Kollisionen mit einem feststehenden Target paarweise $B$-Hadronen zu erzeugen. Die Wechselwirkungen werden in einem Vorw\"artsspektrometer mit etwa 600.000 Auslesekan\"alen nachgewiesen. Aufgrund der relativ niedrigen Schwerpunktsenergie von 41.6\,GeV sind Ereignisse mit $b$-Quarks im Vergleich zu Wechselwirkungen mit leichteren Quarks um etwa sechs Gr\"o{\ss}enordnungen unterdr\"uckt. Die Selektion von Signalereignissen stellt daher eine besondere Herausforderung dar. Sie wird von einem vierstufigen Datennahme- und Triggerystem \"ubernommen, das die Ereignisrate von 10\,MHz auf etwa 20\,Hz reduziert. Neben speziell entwickelter Elektronik werden im Triggersystem mehrere hundert handels\"ubliche PCs eingesetzt. Die Computer sind in zwei so genannten PC-Farmen mit jeweils mehr als 200 Prozessoren angeordnet, die die Rechenkapazit\"at f\"ur Triggerentscheidungen und die prompte Analyse der Ereignisdaten zur Verf\"ugung stellen. Auf der einen Farm laufen schnelle Triggerprogramme mit einer Rechenzeit von etwa 1--100\,ms pro Ereignis ab. Die andere Farm rekonstruiert die Ereignisse online, bevor die Daten auf Band dauerhaft archiviert werden. Die pro Ereignis aufgewandte Rechenzeit liegt dabei im Bereich einiger Sekunden. Die vorliegende Arbeit behandelt zwei Themenkreise. Einerseits wird die technische Umsetzung der Trigger- und der Rekonstruktionsfarm beschrieben. Besonderes Augenmerk liegt dabei auf den Software-Systemen, die den Farmen erforderliche Kalibrationsdaten verf\"ugbar machen und die zentrale \"Uberwachung der Ergebnisse der ablaufenden Programme gestatten. Der Hauptteil der Arbeit besch\"aftigt sich mit Algorithmen f\"ur eine dritte Triggerstufe, die zus\"atzlich zu existierenden Programmen auf der Triggerfarm zum Einsatz kommen sollen. Der Zerfall $B^0(\bar{B}^0)\to J/\psi X$ hat eine sehr klare Signatur, wenn das $J/\psi$ in ein $e^+e^-$- oder $\mu^+\mu^-$-Paar zerf\"allt. Im Triggersystem wird nach einem Paar entgegengesetzt geladener Leptonen des gleichen Typs gesucht, deren invariante Masse der des $J/\psi$ entspricht und deren Spuren von einem gemeinsamen Vertex in der N\"ahe des Targets ausgehen. Es wird davon ausgegangen, dass die Ausnutzung aller kinematischen Zwangsbedingungen ausreicht, um diesen Zerfallskanal klar von Untergrundereignissen zu trennen. Die dritte Triggerstufe soll dagegen auf Signalprozesse mit weniger kinematischen Beschr\"ankungen angewandt werden. Solche Ereignisse entstehen zum Beispiel dann, wenn zwei in der Proton-Target-Kollision erzeugte $B$-Mesonen semileptonisch zerfallen. Das Triggersystem selektiert lediglich die beiden Leptonen, die aber hier nicht von einem gemeinsamen Vertex kommen. Die dritte Triggerstufe soll f\"ur derartige Zerfallstopologien innerhalb von 100\,ms pro Ereignis weitere Kriterien zur Unterscheidung von Signal- und Untergrundprozessen aus den Daten extrahieren. In der Arbeit wird anhand von Monte-Carlo-Studien untersucht, inwieweit die Daten des Silizium-Vertexdetektors des Experimentes zur Entscheidungsfindung einer dritten Triggerstufe beitragen k\"onnen. Dabei wird die Rekonstruktion von Spuren aus der Zerfallskaskade der $B$-Hadronen zus\"atzlich zu den von der vorhergehenden Triggerstufe selektierten Lep\-ton\-en an\-ge\-strebt. Mithilfe einer schnellen Mustererkennung f\"ur den Vertexdetektor wird gezeigt, dass das Auffinden aller Spuren und die Anwendung von Triggeralgorithmen innerhalb des vorgegebenen Zeitfensters von 100\,ms m\"oglich sind. Die Bestimmung der Spurparameter nahe der Targetregion macht von der Methode des Kalman-Filters Gebrauch, um der Vielfachstreuung im Detektormaterial Rechnung zu tragen. Dabei tritt das Problem auf, dass weder der Impuls der gefundenen Spuren bekannt ist, noch die Materialverteilung im Vertexdetektor aus Zeitgr\"unden in aller Strenge ber\"ucksichtigt werden kann. Durch geeignete N\"aherungen gelingt es, eine ausreichende Genauigkeit f\"ur die Spurparameter zu erreichen. Die aufgefundenen Teilchen bilden den Ausgangspunkt f\"ur Triggeralgorithmen. Hierbei wird untersucht, welche Methoden am besten geeignet sind, um Signal- und Unter\-grund\-ereignisse voneinander zu trennen. Es erweist sich, dass das Auffinden von Spuren mit gro{\ss}em Impaktparameter aussichtsreichere Ans\"atze als eine Suche nach Sekund\"arvertices bietet. / The HERA-$B$ experiment at Deutsches Elektronen-Synchrotron (DESY) Hamburg aims at investigating the physics of particles containing $b$ quarks. The experiment focusses on measuring CP violation in the system of neutral $B$ mesons. It is expected that the precise determination of the CP asymmetry in the channel $B^0(\bar{B}^0)\to J/\psi K_S^0$ will have an impact on the further development of the Standard Model of Elementary Particle Physics and cosmological theories. The HERA-$B$ experiment uses the proton beam of the HERA storage ring in fixed-target mode. $B$ hadrons are produced in pairs when protons from the beam halo interact with target nuclei. The interactions are recorded by a forward-spectrometer with roughly 600.000 readout channels. At the HERA-$B$ centre-of-mass energy of 42.6\,GeV, the $b\bar{b}$ cross section is only a tiny fraction of the total inelastic cross section. Only one in about 10$^6$ events contains $b$ quarks, which turns the selection of signal events into a particular challenge. The selection is accomplished by a four-stage data acquisition and trigger system reducing the event rate from 10\,MHz to about 20\,Hz. Besides custom-made electronics, several hundreds of PCs are used in the trigger system. The computers are arranged in two so-called PC farms with more than 200 processors each. The PC farms provide the computing capacity for trigger decisions and the prompt analysis of event data. One farm executes fast trigger programs with a computing time of 1--100\,ms per event. The other farm performs online reconstruction of the events before data are archived on tape. The computing time per event is in the range of several seconds. This thesis covers two topics. In the beginning, the technical implementation of the trigger and the reconstruction farm are described. In doing so, emphasis is put on the software systems which make calibration data available to the farms and which provide a centralised view on the results of the executing processes. The principal part of this thesis deals with algorithms for a Third Level Trigger. This trigger is to come into operation on the trigger farm together with existing programs. Processes of the type $B^0(\bar{B}^0)\to J/\psi X$ have a very clean signature when the $J/\psi$ decays to a $e^+e^-$ or $\mu^+\mu^-$ pair. The trigger system attempts to identify two unlike-sign leptons of the same flavour whose invariant mass matches the $J/\psi$. In later steps, the tracks are required to originate from a common vertex close to the target. It is assumed that these kinematic constraints are sufficient to pick out events of this type among the copious background processes. In contrast, the Third Level Trigger is to be applied to signal processes with fewer kinematic constraints. Such events occur for example when two $B$ mesons, which were created in a proton-target collision, decay semileptonically. The trigger system selects merely the two leptons which do not originate from a common vertex in this case. The Third Level Trigger has 100\,ms at its disposal to extract further criteria from the data which can serve to distinguish between signal and background events. This thesis investigates with the aid of Monte-Carlo simulations how the data of the experiment's silicon vertex detector can contribute to the decisions of a Third Level Trigger. The trigger aims at reconstructing tracks from the decay cascade of $B$ mesons in addition to the leptons selected by the preceding trigger levels. A fast pattern recognition for the vertex detector demonstrates that the reconstruction of all tracks and the application of trigger algorithms are possible within the given time slot of 100\,ms. The determination of track parameters in the target region exploits the Kalman-filter method to account for the multiple scattering of particles in the detector material. The application of this method is, however, made difficult by two facts. First, the momentum of the reconstructed tracks is not known. And, second, the material distribution in the detector cannot be taken into consideration in detail due to timing limitations. Adequate approximations for the momentum and the material traversed by a particle help to accomplish a sufficient accuracy of the track parameters. The reconstructed tracks constitute the starting point of several trigger algorithms, whose suitability to select signal events is investigated. Our studies indicate that the reconstruction of tracks with large impact parameters is a more promising approach than a search for secondary vertices.

In dieser Arbeit wird eine Messung des totalen {\ttb} Produktions-Wirkungsquerschnitts im Einzellepton-Kanal vorgestellt. Der Wirkungsquerschnitt wird mittels einer Profile-Likelihood-Anpassung von Templates bestimmt, welche \"uber einen Lieklihood-Klassifikator unter Benutzung von vier kinematischen Variablen konstruiert werden. F\"ur ein Top-Quark der Masse $m_t=172.5$ GeV ergibt sich ein gemessener Wirkungsquerschnitt von $178.9 \pm 12$ pb, welcher innerhalb einer Standardabweichung mit den aktuellsten theoretischen Vorhersagen \"uberein stimmt. Um die Massenabh\"angigkeit des experimentellen Wirkungsquerschnitts zu bestimmen, wird die Messung f\"ur sieben weitere Werte der Top-Quarkmasse im Bereich zwischen 140 GeV und 200 GeV wiederholt. Mittels Vergleich dieser Massenabh\"angigkeit mit theoretischen Vorhersagen h\"oherer Ordnung wird die Top-Quarkmasse ermittelt. Diese Methode erlaubt die Bestimmung von zwei verschiedenen theoretischen Massenparametern: der Top-Quarkmasse im On-Shell-Schema $m_t^{\mathrm{pole}}$ sowie der Masse im $\overline{MS}$-Schema $\overline{m}_t(\overline{m}_t)$. Der Messwert mit der h\"ochsten erhaltenen Genauigkeit liegt bei $m_t^{\mathrm{pole}} = 171.2\pm 4.5$ GeV, und wird durch Verwendung der derzeit pr\"azisesten Berechnungen h\"oherer Ordnung im $\overline{MS}$-Schema erhalten. Dieser Wert stimmt innerhalb einer Standardabweichung mit den derzeitig besten Mittelwert von Messungen der Top-Quarkmasse am Tevatron \"uberein. / A measurement of the total {\ttb} production cross section in the single lepton channel is presented. The cross section is extracted in a profile likelihood fit of templates constructed from a likelihood classifier using four kinematic variables. For a top quark of mass $m_t=172.5$ GeV, the measured cross section is $178.9 \pm 12$ pb. The measurement agrees within one-standard deviation with the latest theoretical predictions. The cross section measurement is repeated for seven other values of the top quark mass ranging from 140 GeV to 200 GeV to obtain the mass dependence of the experimental cross section. By comparing this with the mass dependence of different higher-order predictions, the top quark mass is extracted. This method allows the determination of two different theoretical mass parameters: the top quark mass in the on-shell scheme $m_t^{\mathrm{pole}}$ and in the $\overline{MS}$ scheme $\overline{m}_t(\overline{m}_t)$. The most precise measurement obtained is $m_t^{\mathrm{pole}} = 171.2\pm 4.5$ GeV, obtained when employing the most precise higher-order calculations in the $\overline{MS}$ scheme. This value agrees within one-standard deviation with the latest Tevatron average of the best top quark mass measurements.