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The PhD thesis offers a long-term investigation of German TV debates with regard to the extent to which the topics dealt with in the debates correspond to the political problems perceived by the voters and whether the actor-specific topics discussed in the TV debates have an influence on the voters' perception of the problems and the perceived responsiveness of the political actors. To this purpose, contents and effects of the Chancellor debates 2002-2013 and the TV debates between 1997 and 2016 are examined at the state level. The empirical investigation is based on an implementation and evaluation of content analyses, the evaluation of opinion polls and the investigation of experimental data on the occasion of the chancellor duels in 2002, 2009 and 2013. The analyses show that TV debates are not only show events, but that the focus of TV debates is on political content (rather than entertaining elements), that the (camp-specific) responsiveness of the format has increased over time, and that successful persuasion - as one of two theme management strategies - by challengers in particular can lead viewers to better assess the effectiveness of the political system.
With 47% land coverage in 2016, agricultural land was one of the largest terrestrial biomes in Germany. About 70% of the agricultural land was cropped area with associated pesticide applications. Agricultural land also represents an essential habitat for amphibians. Therefore, exposure of amphibians to agrochemicals, such as fertilizers and pesticides, seems likely. Pesticides can be highly toxic for amphibians, even a fraction of the original application rate may result in high amphibian mortality.
To evaluate the potential risk of pesticide exposure for amphibians, the temporal coincidence of amphibian presence on agricultural land and pesticide applications (N = 331) was analyzed for the fire-bellied toad (Bombina bombina), moor frog (Rana arvalis), spadefoot toad (Pelobates fuscus) and crested newt (Triturus cristatus) during spring migration. In 2007 and 2008, up to 80% of the migrating amphibians temporally coincided with pesticide applications in the study area of Müncheberg, about 50 km east of Berlin. Pesticide interception by plants ranged between 50 to 90% in winter cereals and 80 to 90% in winter rape. The highest coincidence was observed for the spadefoot toad, where 86.6% of the reproducing population was affected by a single pesticide in winter rape during stem elongation with 80% pesticide interception by plants. Late migrating species, such as the fire-bellied toad and the spadefoot toad, overlapped more with pesticide applications than early migrating species, such as the moor frog, did. Under favorable circumstances, the majority of early migrants may not coincide with the pesticide applications of arable fields during spring migration.
To evaluate the potential effect of pesticide applications on populations of the common frog (Rana temporaria), a landscape genetic study was conducted in the vinicultural area of Southern Palatinate. Due to small sample sizes at breeding sites within viniculture, several DNA sampling methods were tested. Furthermore, the novel repeated randomized selection of genotypes approach was developed to utilize genetic data from siblings for more reliable estimates of genetic parameters. Genetic analyses highlighted three of the breeding site populations located in viniculture as isolated from the meta-population. Genetic differentiation among breeding site populations in the viniculture (median pairwise FST=0.0215 at 2.34 km to 0.0987 at 2.39 km distance) was higher compared to genetic differentiation among breeding site populations in the Palatinate Forest (median pairwise FST=0.0041 at 5.39 km to 0.0159 at 9.40 km distance).
The presented studies add valuable information about the risk of pesticide exposure for amphibians in the terrestrial life stage and possible effects of agricultural land on amphibian meta-populations. To conserve endemic amphibian species and their (genetic) diversity in the long run, the risk assessment of pesticides and applied agricultural management measures need to be adjusted to protect amphibians adequately. In addition, other conservation measures such as the creation of new suitable breeding site should be considered to improve connectivity between breeding site populations and ensure the persistence of amphibians in the agricultural land.
Within aquatic environments sediment water interfaces (SWIs) are the most important areas concerning exchange processes between the water body and the sediment. These spatially restricted regions are characterized by steep biogeochemical gradients that determine the speciation and fate of natural or artificial substances. Apart from biological mediated processes (e.g., burrowing organisms, photosynthesis) the determining exchange processes are diffusion or a colloid-mediated transport. Hence, methods are required enabling to capture the fine scale structures at the boundary layer and to distinguish between the different transport pathways. Regarding emerging substances that will probably reach the aquatic environment engineered nanomaterials (ENMs) are of great concern due to their increased use in many products and applications. Since they are determined based on their size (<100 nm) they include a variety of different materials behaving differently in the environment. Once released, they will inevitable mix with naturally present colloids (< 1 μm) including natural nanomaterials.
With regard to existing methodological gaps concerning the characterization of ENMs (as emerging substances) and the investigation of SWIs (as receiving environmental compartments), the aim of this thesis was to develop, validate and apply suitable analytical tools. The challenges were to i) develop methods that enable a high resolution and low-invasive sampling of sediment pore water. To ii) develop routine-suitable methods for the characterization of metal-based engineered nanoparticles and iii) to adopt and optimize size-fractionation approaches for pore water samples of sediment depth profiles to obtain size-related information on element distributions at SWIs.
Within the first part, an available microprofiling system was combined with a novel micro sampling system equipped with newly developed sample filtration-probes. The system was thoroughly validated and applied to a freshwater sediment proving the applicability for an automatic sampling of sediment pore waters in parallel to microsensor measurements. Thereby, for the first time multi-element information for sediment depth profiles were obtained at a millimeter scale that could directly be related to simultaneously measured sediment parameters.
Due to the expected release of ENMs to the environment the aim was to develop methods that enable the investigation of fate and transport of ENMs at sediment water interfaces. Since standardized approaches are still lacking, methods were developed for the determination of the total mass concentration and the determination of the dissolved fraction of (nano)particle suspensions. Thereby, validated, routine suitable methods were provided enabling for the first time a routine-suitable determination of these two, among the most important properties regarding the analyses of colloidal systems, also urgently needed as a basis for the development of appropriate (future) risk assessments and regulatory frameworks. Based on this methodological basis, approaches were developed enabling to distinguish between dissolved and colloidal fractions of sediment pore waters. This made it possible for the first time to obtain fraction related element information for sediment depth profiles at a millimeter scale, capturing the fine scale structures and distinguishing between diffusion and colloid-mediated transport. In addition to the research oriented parts of this thesis, questions concerning the regulation of ENPs in the case of a release into aquatic systems were addressed in a separate publication (included in the Appendix) discussing the topic against the background of the currently valid German water legislation and the actual state of the research.
Navigation is a natural way to explore and discover content in a digital environment. Hence, providers of online information systems such as Wikipedia---a free online encyclopedia---are interested in providing navigational support to their users. To this end, an essential task approached in this thesis is the analysis and modeling of navigational user behavior in information networks with the goal of paving the way for the improvement and maintenance of web-based systems. Using large-scale log data from Wikipedia, this thesis first studies information access by contrasting search and navigation as the two main information access paradigms on the Web. Second, this thesis validates and builds upon existing navigational hypotheses to introduce an adaptation of the well-known PageRank algorithm. This adaptation is an improvement of the standard PageRank random surfer navigation model that results in a more "reasonable surfer" by accounting for the visual position of links, the information network regions they lead to, and the textual similarity between the link source and target articles. Finally, using agent-based simulations, this thesis compares user models that have a different knowledge of the network topology in order to investigate the amount and type of network topological information needed for efficient navigation. An evaluation of agents' success on four different networks reveals that in order to navigate efficiently, users require only a small amount of high-quality knowledge of the network topology. Aside from the direct benefits to content ranking provided by the "reasonable surfer" version of PageRank, the empirical insights presented in this thesis may also have an impact on system design decisions and Wikipedia editor guidelines, i.e., for link placement and webpage layout.
Assessment of renewable energy potentials based on GIS. A case study in southwest region of Russia
(2018)
In the present thesis, the initial conditions for the development of RES potentials for the production of wind, solar and biomass energy in the Krasnodar region (southwestern region of the Russian Federation) are examined using a multi-criteria assessment methodology. For the assessment of the RES potentials at regional scale, the prosed multi-criteria methodology based on the geographic information systems (GIS) and has been complemented by the evaluation and analysis of primary and secondary data as well as economic calculations relevant related to economic feasibility of RES projects.
The cytological examination of bone marrow serves as clarification of variations in blood smears. It is also used for the clarification of anemia, as exclusion of bone marrow affection at lymphoma and at suspicion of leukemia. The morphological evaluation of hematopoietic cells is the basis for the creation of the diagnosis and for decision support for further diagnostics. Even for experienced hematologists the manual classification of hematopoietic cells is time-consuming, error-prone and subjective. For this reason new methods in the field of image processing and pattern recognition for the automatic classification including preprocessing steps are developed for a computer-assisted microscopy system. These methods are evaluated by means of a huge reference database. The proposed image analysis procedures comprise methods for the automated detection of smears, for the determination of relevant regions, for the localization and segmentation of single hematopoietic cells as well as for the feature extraction and classification task. These methods provide the basis for the first system for the automated, morphological analysis of bone marrow aspirates for leukemia diagnosis and are therefore a major contribution for a better and more efficient patient care in the future.
Technologische Fortschritte auf dem Gebiet der integrierten Halbleitertechnik, die unter anderem auch zur gestiegenen Leistungsfähigkeit der Kamerasensoren beitragen, konzentrierten sich bisher primär auf die Schnelligkeit und das Auflösungsvermögen der Sensoren. Die sich ständig verändernde Entwicklung hat jedoch direkte Folgen auf das physikalische Verhalten einer Kamera und damit auch Konsequenzen für die erreichbare geometrische Genauigkeit einer photogrammetrischen 3D-Rekonstruktion. Letztere stand bisher nicht im Fokus der Forschung und ist eine Aufgabe, der sich diese Arbeit im Sinne der Photogrammetrie und Messtechnik stellt. Aktuelle Untersuchungen und Erfahrungen aus industriellen Projekten zeigen in diesem Zusammenhang, dass das geometrisch-physikalische Verhalten digitaler Kameras - für höchste photogrammetrische Ansprüche - noch nicht ausreichend modelliert ist. Direkte Aussagen zur erreichbaren Genauigkeit bei gegebener Hardware erweisen sich daher bislang als unzureichend. Ferner kommt es aufgrund der unpräzisen Modellierung zu Einbußen in der Zuverlässigkeit der erreichten Ergebnisse. Für den Entwickler präziser kamerabasierter Messverfahren folgt daraus, dass zu einer optimalen Schätzung der geometrischen Genauigkeit und damit auch vollständigen Ausschöpfung der Messkamera geeignete mathematische Modelle erforderlich sind, die das geometrisch physikalische Verhalten bestmöglich beschreiben. Diese Arbeit beschreibt, wie die erreichbare Genauigkeit einer Bündelblockausgleichung, schon a priori mithilfe des EMVA1288 Standards approximiert werden kann. Eine in diesem Zusammenhang wichtige Teilaufgabe ist die Schaffung einer optimalen Messanordnung. Hierzu gehören Untersuchungen der üblicherweise verwendeten Kalibrierkörper und die Beseitigung von systematischen Fehlern vor und nach der Bündelblockausgleichung. Zum Nachweis dieser Systematiken wird eine auf statistischem Lernen basierende Methode beschrieben und untersucht. Erst wenn alle genauigkeitsmindernden Einflüsse berücksichtigt sind, wird der Anteil des Sensors in den Messdaten sichtbar und damit auch mathematisch parametrisierbar. Die Beschreibung des Sensoreinflusses auf die erreichbare Genauigkeit der Bündelblockausgleichung erfolgt in drei Schritten. Der erste Schritt beschreibt den Zusammenhang zwischen ausgewählten EMVA1288-Kennzahlen und der Unsicherheit eines Grauwertes. Der zweite Schritt ist eine Modellierung dieser Grauwertunsicherheit als Zentrumsunsicherheit einer Zielmarke. Zur Beschreibung dieser Unsicherheit innerhalb der Bündelblockausgleichung wird ein stochastisches Modell, basierend auf dem EMVA1288-Standard, vorgeschlagen. Ausgehend vom Rauschen des Zielmarkenmittelpunktes wird im dritten Schritt die Unsicherheit im Objektraum beispielhaft mit Hilfe von physikalisch orientierten Simulationen approximiert. Die Wirkung der vorgeschlagenen Methoden wird anhand von Realkalibrierungen nachgewiesen. Abschließend erfolgt die Diskussion der vorgeschlagenen Methoden und erreichten Ergebnisse sowie ein Ausblick auf kommende Untersuchungen.
Changing Lives through Relocation - Ethnography of a Socialized Housing Project in the Philippines
(2018)
Changing lives through relocation - This is the vision of a socialized housing project in the Philippines which is subject of this dissertation. It is a polyphonic ethnography that investigates the transition process from an informal, marginalized, self-organized lifestyle in squatter areas and dumpsite settlements to an institutionalized and policy-based life in the socialized housing project. The transition process is analyzed from a material cultural perspective taking into account selected aesthetic theories. With this approach, the dissertation aims to contribute to the study of the aesthetic dimension of everyday life from an ethnographic perspective. Aesthetics are applied on three levels: (1) On the theoretical level, the concepts of social aesthetics and atmospheres enrich the analysis of the interrelation between the residents and their new house in the socialized housing project. (2) On the methodological level, the relevance of aesthetic experiences for the ethnographic knowledge process are discussed. And (3) on the descriptive level, selected and thematically relevant sensory and aesthetic experiences of the researcher inform the ethnographic account in the form of memoirs. By incorporating aesthetic theories, the dissertation gives a more holistic account of the dynamics active in the transition process. It shows that the change of lifestyle is experienced sensorily through the daily physical engagement with the new material environment, i.e. its specific materiality and infrastructure, its affordances and constraints giving rise to new experiences and needs. In this process, the residents become aware of the differences between the past and present way of life and thus experience the new challenges through their physical being in the new material environment. On the one hand, this evokes a nostalgic attitude towards their previous life, but on the other hand, it also gives form to ideas of a possible future.
The primary aims of the study are (1) to identify classroom instructional factors which have a crucial effect on the academic growth of ninth-graders in EFL in Vietnam, and (2) to gain insight into their interplay with each other and with context factors. Besides, this study has a strong focus on methodological approaches: (a) using multiple methods in order to deal with the “large p, small n” problem, (b) to understand the relevance of the scaling model used for the results.
Data from a research project carried out in Vietnam during the school year 2006–2007 were used in this study. Besides a longitudinal design with two measurement points (MPs) using adapted English tests and questionnaires from the DESI-study in Germany, a video study was conducted in the middle of the school year between two MPs. The recorded video data were transcribed, micro-analytically coded, and lessons were rated to gain indicators of classroom instruction. Different IRT scaling models were chosen to estimate student ability in the pretest and posttest. For the C-test, the unidimensional 1PL and 2PL models, the Rasch testlet model, and testlet 2PL model were selected to model student ability. To estimate student ability via the listening comprehension test (LC-test), the Rasch model, the unidimensional 2PL, and 3PL models were applied. The student ability estimates at the two MPs were linked to one common scale using the concurrent calibration approach with different a priori ability distributions. The plausible values (PVs) were generated and treated as student ability estimates for all analyses. To understand the relationship between the instructional variables and student growth, we explored the hypothesized linear and nonlinear, additive and interactive effects of classroom instructional factors. To examine these hypothetical effects, OLS and regularized regression models using lasso (least absolute shrinkage and selection operators) were applied, including main effects as well as quadratic and interaction terms of instructional variables. Initial student ability and the socioeconomic status of students were treated as context variables.
The results show, on the one hand, a positive view of important general instructional quality dimensions of teaching effectiveness and, on the other hand, a strongly teacher-centered and textbook-driven instruction and poor instructional quality from the point of view of EFL didactics. The most important instructional factors of student growth in the C-test were quality aspects of motivation in instruction as well as aspects related to the teaching language. Regarding the LC-test results, language-related aspects together with the relative frequency of repeated questions were the most important predictors of student growth. While the findings confirmed all the hypothesized instructional effects on student growth, aptitude treatment interaction effects of instruction were only confirmed with regard to student growth in the C-test. The different scaling models produced significant differences in the results regarding instructional effects on student growth.
Tradierte Managementsysteme und primär auf die Erfüllung finanzieller Ziele ausgerichtete Führungsansätze scheinen heute der wirtschaftlichen Dynamik nicht mehr gewachsen. Die Zahl ausgebrannter Führungskräfte und Mitarbeiter nimmt zu. Ebenso der volkswirtschaftliche Schaden durch schlechte Führungsleistung. Zwar beeinflussen externe Faktoren wie globaler Wettbewerb, aufkeimende Handelskriege, die Digitalisierung in Wirtschaft und Gesellschaft die Rahmensetzungen für Unternehmen. Die Entscheidung über Erfolg oder Misserfolg verlagert sich aber signifikant nach Innen.
Diese Arbeit zeigt auf, dass Wissenschaftler und erfolgreiche CEOs einen Paradigmenwechsel fordern, da sie Kommunikationsbereitschaft und Kommunikationsfähigkeit als die relevanten Erfolgsfaktoren identifizieren. Unterstützend bestätigen interdisziplinäre Erkenntnisse und Forschungsergebnisse anderer Disziplinen – speziell der Neurowissenschaften, die Wirksamkeit einer Kommunikationskultur, die alle Sinne des Menschen aktiviert.
Das Phänomen der Kommunikation ganzheitlich zu verstehen und mittels dialogbasiertem Management umzusetzen, wird zum neuen Erfolgsschlüssel und wirkt sich auf alle unternehmerischen Prozesse, Führungs- und Interaktionssituationen aus. Unabhängig von Betriebsgröße und Branche. Die durch Dialog in Gang gesetzte positive reziproke Eskalation führt dazu, dass Kollegen/Mitarbeiter ihr Können und ihr Engagement in viel höherem Maße freiwillig zur Verfügung stellen, als es z.B. finanzielle Anreizsysteme je bewirken können.
Die Empirie dieser Forschungsarbeit spiegelt das Wissen der 22 hoch erfolgreichen österreichischen CEOs, Führungskräfte und Firmeneigentümer über Interne Kommunikation und deren Annäherung an diese Führungsaufgabe wider. In der Folge sind Leit-Ideen das vernetzte Ergebnis der theoretischen und empirischen Analysen. Diese daraus destillierten Leit-Ideen stehen für einen radikal dialogbasierten Kommunikationsansatz, der sämtliche Management-, Geschäfts- und Unterstützungsprozesse determiniert.
Verstehen CEOs und Führungskräften eine dialogbasierte Interne Kommunikation als eindeutig ihnen zufallende Führungsaufgabe, kann heute und in Zukunft die Querschnittsmaterie Interne Kommunikation zum größten Ressourcen-Pool für unternehmerischen Erfolg werden, so die diesbezüglichen Schlussfolgerungen.