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Arbeitgeberreputation und Mitarbeiterverhalten in sozialen Netzwerken
No full textDie Reputation von Unternehmen ist einer zunehmenden Gefahr ausgesetzt, die sich aus der (unreflektierten) Nutzung sozialer Netzwerke durch die eigenen Mitarbeiter ergibt. Die Treiber und Hemmnisse eines solchen Nutzerverhaltens von Arbeitnehmern in sozialen Netzwerken wurden bislang nur unzureichend erforscht. Der vorliegende Beitrag untersucht unter Verwendung der Boundary Theorie am Beispiel der Plattform Facebook, inwieweit die Persönlichkeitsmerkmale Neurotizismus und Extraversion, die Organisationsidentifikation und die Unternehmensreputation ein zustimmendes Verhalten von Nutzern begünstigen. Eine experimentelle Online-Studie mit 494 Probanden zeigt, dass insbesondere eine hohe Unternehmensreputation und Organisationsidentifikation zu einem erhöhten zustimmenden Verhalten führen
Comparison of mobile applications for enterprise content management systems
No full textThis thesis is providing an overview over the current topics and influences of mobile components on Enterprise Content Management (ECM). With a literature review the core topics of enterprise mobility and ECM have been identified and projected on the context of using mobile Apps within the environment of ECM. An analysis of three ECM systems and their mobile software lead to an understanding of the functionalities and capabilities mobile systems are providing in the ECM environment. These findings lead to a better un- derstanding for the usage of mobile Enterprise Content Management and is preparation. The thesis focuses the most important topics, which need to be considered for the usage and adoption of mobile Apps in ECM
Veranstaltungsverzeichnis Sommersemester 2016 - Landau
Get PDFVeranstaltungsverzeichnis - Landau - Sommersemester 201
Effects of fungicides on decomposer communities and litter decomposition in streams
Get PDFAgriculture covers one third of the world land area and has become a major source of water pollution due to its heavy reliance on chemical inputs, namely fertilisers and pesticides. Several thousands of tonnes of these chemicals are applied worldwide annually and partly reach freshwaters. Despite their widespread use and relatively unspecific modes of action, fungicides are the least studied group of pesticides. It remains unclear whether the taxonomic groups used in pesticide risk assessment are protective for non-target freshwater fungi. Fungi and bacteria are the main microbial decomposers converting allochthonous organic matter (litter) into a more nutritious food resource for leaf-shredding macroinvertebrates. This process of litter decomposition (LD) is central for aquatic ecosystem because it fuels local and downstream food webs with energy and nutrients. Effects of fungicides on decomposer communities and LD have been mainly analysed under laboratory conditions with limited representation of the multiple factors that may moderate effects in the field.
In this thesis a field study was conducted in a German vineyard area to characterise recurrent episodic exposure to fungicides in agricultural streams (chapter 2) and its effects on decomposer communities and LD (chapter 3). Additionally, potential interaction effects of nutrient enrichment and fungicides on decomposer communities and LD were analysed in a mesocosm experiment (chapter 4).
In the field study event-driven water sampling (EDS) and passive sampling with EmporeTM styrene-divinylbenzene reverse phase sulfonated disks (SDB disks) were used to assess exposure to 15 fungicides and 4 insecticides. A total of 17 streams were monitored during 4 rainfall events within the local application period of fungicides in 2012. EDS exceeded the time-weighted average concentrations provided by the SDB disks by a factor of 3, though high variability among compounds was observed. Most compounds were detected in more than half of the sites and mean and maximum peak (EDS) concentrations were under 1 and 3 µg/l, respectively. Besides, SDB disk-sampling rates and a free-software solution to derive sampling rates under time-variable exposure were provided.
Several biotic endpoints related to decomposers and LD were measured in the same sampling sites as the fungicide monitoring, coinciding with the major litter input period. Our results suggest that polar organic fungicides in streams change the structure of the fungal community. Causality of this finding was supported by a subsequent microcosm experiment. Whether other effects observed in the field study, such as reduced fungal biomass, increased bacterial density or reduced microbial LD can be attributed to fungicides remains speculative and requires further investigation. By contrast, neither the invertebrate LD nor in-situ measured gammarid feeding rates correlated with water-borne fungicide toxicity, but both were negatively associated with sediment copper concentrations. The mesocosm experiment showed that fungicides and nutrients affect microbial decomposers differently and that they can alter community structure, though longer experiments are needed to determine whether these changes may propagate to invertebrate communities and LD. Overall, further studies should include representative field surveys in terms of fungicide pollution and physical, chemical and biological conditions. This should be combined with experiments under controlled conditions to test for the causality of field observations
Impact of fungicides on an aquatic decomposer-detritivore system
Get PDFLeaf litter breakdown is a fundamental process in aquatic ecosystems, being mainly mediated by decomposer-detritivore systems that are composed of microbial decomposers and leaf-shredding, detritivorous invertebrates. The ecological integrity of these systems can, however, be disturbed, amongst others, by chemical stressors. Fungicides might pose a particular risk as they can have negative effects on the involved microbial decomposers but may also affect shredders via both waterborne toxicity and their diet; the latter by toxic effects due to dietary exposure as a result of fungicides’ accumulation on leaf material and by negatively affecting fungal leaf decomposers, on which shredders’ nutrition heavily relies. The primary aim of this thesis was therefore to provide an in-depth assessment of the ecotoxicological implications of fungicides in a model decomposer-detritivore system using a tiered experimental approach to investigate (1) waterborne toxicity in a model shredder, i.e., Gammarus fossarum, (2) structural and functional implications in leaf-associated microbial communities, and (3) the relative importance of waterborne and diet-related effects for the model shredder.
Additionally, knowledge gaps were tackled that were related to potential differences in the ecotoxicological impact of inorganic (also authorized for organic farming in large parts of the world) and organic fungicides, the mixture toxicity of these substances, the field-relevance of their effects, and the appropriateness of current environmental risk assessment (ERA).
In the course of this thesis, major differences in the effects of inorganic and organic fungicides on the model decomposer-detritivore system were uncovered; e.g., the palatability of leaves for G. fossarum was increased by inorganic fungicides but deteriorated by organic substances. Furthermore, non-additive action of fungicides was observed, rendering mixture effects of these substances hardly predictable. While the relative importance of the waterborne and diet-related effect pathway for the model shredder seems to depend on the fungicide group and the exposure concentration, it was demonstrated that neither path must be ignored due to additive action. Finally, it was shown that effects can be expected at field-relevant fungicide levels and that current ERA may provide insufficient protection for decomposer-detritivore systems. To safeguard aquatic ecosystem functioning, this thesis thus recommends including leaf-associated microbial communities and long-term feeding studies using detritus feeders in ERA testing schemes, and identifies several knowledge gaps whose filling seems mandatory to develop further reasonable refinements for fungicide ERA
Funktionelle Erweiterung und Anpassung für das Mikrosimulationsprogramm CoMicS im Bereich der grafischen Ergebnisausgabe
No full textDiese Arbeit befasst sich mit der grafischen Ergebnisauswertung bei Mikrosimulationsprogrammen. Konkret für die vorhandene Software "CoMicS" eine Erweiterung implementiert, die es erlaubt die errechneten Daten einer Simulation visuell zu explorieren
Terrainklassifikation mit Markov Zufallsfeldern für autonome Roboter in unstrukturiertem Terrain
No full textThis thesis addresses the problem of terrain classification in unstructured outdoor environments. Terrain classification includes the detection of obstacles and passable areas as well as the analysis of ground surfaces. A 3D laser range finder is used as primary sensor for perceiving the surroundings of the robot. First of all, a grid structure is introduced for data reduction. The chosen data representation allows for multi-sensor integration, e.g., cameras for color and texture information or further laser range finders for improved data density. Subsequently, features are computed for each terrain cell within the grid. Classification is performedrnwith a Markov random field for context-sensitivity and to compensate for sensor noise and varying data density within the grid. A Gibbs sampler is used for optimization and is parallelized on the CPU and GPU in order to achieve real-time performance. Dynamic obstacles are detected and tracked using different state-of-the-art approaches. The resulting information - where other traffic participants move and are going to move to - is used to perform inference in regions where the terrain surface is partially or completely invisible for the sensors. Algorithms are tested and validated on different autonomous robot platforms and the evaluation is carried out with human-annotated ground truth maps of millions of measurements. The terrain classification approach of this thesis proved reliable in all real-time scenarios and domains and yielded new insights. Furthermore, if combined with a path planning algorithm, it enables full autonomy for all kinds of wheeled outdoor robots in natural outdoor environments.Diese Doktorarbeit beschäftigt sich mit dem Problem der Terrainklassifikation im unstrukturierten Außengelände. Die Terrainklassifikation umfasst dabei das Erkennen von Hindernissen und flachen Bereichen mit der einhergehenden Analyse der Bodenoberfläche. Ein 3D Laser-Entfernungsmesser wurde als primärer Sensor verwendet, um das Umfeld des Roboters zu vermessen. Zunächst wird eine Gitterstruktur zur Reduktion der Daten eingeführt. Diese Datenrepräsentation ermöglicht die Integration mehrerer Sensoren, z.B. Kameras für Farb- und Texturinformationen oder weitere Laser-Entfernungsmesser, um die Datendichte zu erhöhen. Anschließend werden für alle Terrainzellen des Gitters Merkmale berechnet. Die Klassifikation erfolgt mithilfe eines Markov Zufallsfeldes für Kontextsensitivität um Sensorrauschen und variierender Datendichte entgegenzuwirken. Ein Gibbs-Sampling Ansatz wird zur Optimierung eingesetzt und auf der CPU sowie der auf GPU parallelisiert um Ergebnisse in Echtzeit zu berechnen. Weiterhin werden dynamische Hindernisse unter Verwendung verschiedener State-of-the-Art Techniken erkannt und über die Zeit verfolgt. Die berechneten Informationen, wohin sich andere Verkehrsteilnehmer bewegen und in Zukunft hinbewegen könnten, werden verwendet, um Rückschlüsse auf Bodenoberflächen zu ziehen die teilweise oder vollständig unsichtbar für die Sensoren sind. Die Algorithmen wurden auf unterschiedlichen autonomen Roboter-Plattformen getestet und eine Evaluation gegen von Menschen annotierte Grundwahrheiten von Karten aus mehreren Millionen Messungen wird präsentiert. Der in dieser Arbeit entwickelte Ansatz zur Terrainklassifikation hat sich in allen Anwendungsbereichen bewährt und neue Erkenntnisse geliefert. Kombiniert mit einem Pfadplanungsalgorithmus ermöglicht die Terrainklassifikation die vollständige Autonomie für radgetriebene Roboter in natürlichem Außengelände
Mitteilungsblatt der Universität Koblenz-Landau Nr. 4/2015
No full textZwölfte Ordnung zur Änderung der Prüfungsordnung für die Prüfung im lehramtsbezogenen Bachelorstudiengang an der Universität Koblenz-Landau
Elfte Ordnung zur Änderung der Prüfungsordnung für die Prüfung in den Masterstudiengängen für das Lehramt an Grundschulen, das Lehramt an Realschulen plus, das Lehramt an Förderschulen sowie das Lehramt an Gymnasien an der Universität Koblenz-Landau
Zehnte Ordnung zur Änderung der Ordnung für die Prüfung im lehramtsbezogenen Zertifikatsstudiengang (Erweiterungsprüfung) an der Universität Koblenz-Landau
Neunte Ordnung zur Änderung der Prüfungsordnung für die Prüfung im Zwei-Fach-Bachelorstudiengang an der Universität Koblenz-Landau
Vierte Ordnung zur Änderung der Gemeinsamen Prüfungsordnung für Studierende des Bachelorstudiengangs und des Masterstudiengangs "Kulturwissenschaft" des Fachbereichs 2: Philologie / Kulturwissenschaften an der Universität Koblenz-Landau
Dritte Ordnung zur Änderung der Ordnung für die Prüfung im Bachelorstudiengang Umweltwissenschaften und in den Masterstudiengängen Umweltwissenschaften und Ecotoxicology an der Universität Koblenz-Landau, Campus Landau
Ordnung zur Änderung der Einschreibeordnung für die Universität Koblenz-Landau
Habilitationsordnung des Fachbereichs 5: Erziehungswissenschaften der Universität Koblenz-Landa
Uniprisma Ausg. 2009
No full text30 Jahre Informatik
Jugendstil-Tagung
Sprit aus Regenwäldern
Musikfestival Koblen
Einführung in die Kryptographie sowie die Informations- und Codierungstheorie
No full textVorlesungsskript für eine vierstündige Vorlesung im Master Mathematik oder Informati