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With the emergence of current generation head-mounted displays (HMDs), virtual reality (VR) is regaining much interest in the field of medical imaging and diagnosis. Room-scale exploration of CT or MRI data in virtual reality feels like an intuitive application. However in VR retaining a high frame rate is more critical than for conventional user interaction seated in front of a screen. There is strong scientific evidence suggesting that low frame rates and high latency have a strong influence on the appearance of cybersickness. This thesis explores two practical approaches to overcome the high computational cost of volume rendering for virtual reality. One lies within the exploitation of coherency properties of the especially costly stereoscopic rendering setup. The main contribution is the development and evaluation of a novel acceleration technique for stereoscopic GPU ray casting. Additionally, an asynchronous rendering approach is pursued to minimize the amount of latency in the system. A selection of image warping techniques has been implemented and evaluated methodically, assessing the applicability for VR volume rendering.
This Work analyzes if a hardware prototype on an Arduino basis for an Adhoc Network can be created. The objective of the prototype development is, the creation of a sensor node with a modular design, where components can be easily changed. Furthermore the application area has requirements, which the node must fulfill. These requirements are derived from the Tmote Sky sensor node, therefore the new created sensor node must be a possible alternative for it and fulfill the same functions. For that purpose this study reviews some available Arduino microprocessors on their suitability for a sensor node. Later in the work the composition of the sensor node is documented. For this, the hardware and their costs are illustrated. The created hardware prototype allows, through easily changed radio modules, the covering of 433 MHz, 866 MHz and 2,40 GHz radio frequencies. At the end of the work, the sensor node prototype is used in an experiment to check for the suitability for water monitoring. For this, an experiment was performed on land and on water and the results evaluated. In the end the prototype fulfilled most of the requirements, but the cost was a little too high.
This bachelor thesis deals with the development of an application for the Microsoft HoloLens. The application is used for the marketing of advertis- ing spaces that belongs to the company awk AUSSENWERBUNG GmbH. On basis of the development, the question is answered which are the pos- sibilities and limitations of the HoloLens and the Mixed Reality Platform. Problems are also addressed, that come along with the development of an application for such a new technology, like the HoloLens is. Beside the new technologies, some challenges come also from the applications oper- ational locations. Several application examples and presentations suggest, that the HoloLens is primarily designed for indoor usage. Instead the de- veloped application is for outdoor use only. During the development, sev- eral insights can be gained about this new technology. On the one hand it becomes clear, that the HoloLens and also the development environment aren’t completely matured yet. On the other hand, that the HoloLens isn’t an outdoor device at all. Despite the difficulties during the development, there occur many possibilities that are associated with this new technology.
Im schulischen Kontext wird dem Prozess der Erkenntnisgewinnung in eigenverantwortlichen Lernprozessen immer mehr Bedeutung beigemessen. Experimentelles Arbeiten wird in den nationalen Bildungsstandards als Prozess beschrieben, welcher vier Teil-schritte durchläuft: (1) Fragestellung entwickeln, (2) Experimente durchführen, (3) Daten notieren und (4) Schlussfolgerung ziehen [1]. In der fachdidaktischen Forschung gibt es bisher keine Untersuchungen, die explizit den Teilschritt der Datenaufnahme und dessen Bedeutung behandeln.
In dieser Arbeit werden die unterschiedlichen Definitionen der naturwissenschaftlichen Protokollformen voneinander abgegrenzt sowie im Rahmen von drei Teilstudien die Bedeutung des Protokollierens für die Lernwirksamkeit untersucht. Zusätzlich wird eine Auswertungsmethode für die Qualität von Erarbeitungsprotokollen vorgestellt.
This thesis tests several methods and measures in pathtracing for selecting either the Line Space or the Bounding Volume Hierarchy data structure to make use of the advantages of both. The structures are defined locally around each object and each Line Space shaft contains one candidate ID each. All implementation is done as a C++ and OpenGL framework with compute shaders handling the pathtracing and Line Space generation. The measures include the probability distribution, the effect dependency, as well as a distance threshold and are tested against several different scenes. In most situations, the results show a noticeable increase in performance, partly only with minor visual differences, with the probability measure producing the highest quality images for a given performance. The fundamental problems of the Line Space concering the high memory consumption and a long generation time compared to the BVH still persist, despite the object local structure, a minimal amount of data per shaft and the compute shader implementation.
Campuszeitung Ausg. 1/2017
(2017)
Coordination and awareness mechanisms are important in systems for Computer-Supported Cooperative Work (CSCW) and traditional groupware systems. It has been a key focus of research into collaborative groupware and its capability to enable people to efficiently collaborate and coordinate work. Until now, no classification of the mechanisms has been undertaken to identify commonalities and differences in coordination and awareness mechanisms and to show their significance in collaborative environments. In addition, there is a little investigation of coordination and awareness mechanisms in new forms of groupware such as socially enabled Enterprise Collaboration Systems (ECS). Indeed, both in science and in practices, ECS incorporating social software have become increasingly important. Based on the combination of traditional groupware and social software, ECS also include coordination and awareness mechanisms that may simplify collaboration, but these have not yet been investigated.
Therefore, the aim of this thesis is to identify coordination and awareness mechanisms in the academic literature to provide a general overview of those mechanisms examples. Additionally, this thesis aims to classify the mechanism examples. Based on a deep literature analysis, concepts described in literature are chosen and applied with the intension to analyse the mechanisms and to reach a classification. Based on the classification of the identified mechanisms their commonalities and differences are examined and described to gain a better understanding of them. For illustration purpose, examples of coordination and awareness mechanisms and their application are portrayed. The mechanisms examples refer to the classification groups derived. The selection of the mechanisms for the visualization is based on significant differences in their functionality. Subsequently, the selected mechanisms, more based on traditional groupware, are checked to a limited extend whether they can be found in socially enabled ECS. The collaborative platform of IBM Connections serves as a practical example of ECS incorporating social software. IBM Connections is used at the University of Koblenz to run the platform "UniConnect". On the platform it is investigated which of the identified mechanisms examples of the literature are applied in IBM Connections and which additional mechanisms are created by users. This work is the first step in the study of coordination and awareness mechanisms in socially-enabled ECS. In addition, it is expected to detect new mechanisms which are used while the social factor to collaborative work is new.
The purpose of this thesis is to examine and collect coordination and awareness mechanisms examples in literature to analyse them. Additionally, the purpose is to provide a first overview of mechanisms and to classify them by investigating their commonalities. Beside this thesis should give incentive for further investigations to investigate coordination and awareness mechanisms in socially integrated ECS.
The European weatherfish (Misgurnus fossilis) is a benthic freshwater fish species belonging to the family Cobitidae, that is subjected to a considerable decline in many regions across its original distribution range. Due to its cryptic behavior and low economic value, the causes of threat to weatherfish remained partly unknown and the species is rarely at the center of conservation efforts. In order to address these concerns, the overall aim of the present thesis was to provide a comprehensive approach for weatherfish conservation, including the development of stocking measures, investigations on the species autecology and the evaluation of potential threats. The first objective was to devise and implement a regional reintroduction and stock enhancement program with hatchery-reared weatherfish in Germany. Within this program (2014-2016), a total number of 168,500 juvenile weatherfish were stocked to seven water systems. Recaptures of 45 individuals at two reintroduction sites supported the conclusion that the developed stocking strategy was appropriate. In order to broaden the knowledge about weatherfish autecology and thereby refining the rearing conditions and the selection of appropriate stocking waters, the second objective was to investigate the thermal requirements of weatherfish larvae. Here, the obtained results revealed that temperatures higher than previously suggested were tolerated by larvae, whereas low temperatures within the range of likely habitat conditions increased mortality rates. As weatherfish can be frequently found in agriculturally impacted waters (e.g. ditch systems), they are assumed to have an increased probability to be exposed to chemical stress. Since the resulting risk has not yet been investigated with a focus on weatherfish, the third objective was to provide a methodical foundation for toxicity testing that additionally complies with the requirements of alternative test methods. For this purpose, the acute fish embryo toxicity test was successfully transferred to weatherfish and first results exhibited that sensitivity of weatherfish towards a tested reference substance (3,4-dichloroaniline) was highest compared to other species. On the basis of these findings, the fourth objective was to apply weatherfish embryos for multiple sediment bioassays in order to investigate teratogenic effects derived from sediment-associated contaminants. In this context, weatherfish revealed particular sensitivity to water extractable substances, indicating that sediment contamination might pose a considerable risk. Moreover, as an endangered benthic fish species with high ecological relevance for European waters that are specifically exposed to hazardous contaminants, the weatherfish might be a prospective species for an ecological risk assessment of sediment toxicity. Overall, the present thesis contributed to the conservation of weatherfish by considering a variety of aspects that interact and reinforce one another in order to achieve improvements for the species situation.
Die Analyse ortsbezogener Strukturdaten und Merkmale ist eine der wesentlichen Voraussetzungen für die Bewertung von Standorten und Räumen. Durch die Erfassung der lokalen Ausprägung ausgewählter Standortfaktoren und unter Zuhilfenahme eines Geographischen Informationssystems werden in der vorliegenden Dissertation die Städte und Gemeinden des hessischen Rheingau-Taunus-Kreises kategorisiert und miteinander verglichen. Hierbei erfolgt eine besondere Fokussierung auf die lokal bestehende technische und soziale Infrastruktur, um vorrangig das vorhandene Gewerbe- und Wohnumfeld sowie die darüber hinaus existierenden räumlichen Disparitäten eingehend veranschaulichen und beurteilen zu können.
The Internet of Things (IoT) is a network of addressable, physical objects that contain embedded sensing, communication and actuating technologies to sense and interact with their environment (Geschickter 2015). Like every novel paradigm, the IoT sparks interest throughout all domains both in theory and practice, resulting in the development of systems pushing technology to its limits. These limits become apparent when having to manage an increasing number of Things across various contexts. A plethora of IoT architecture proposals have been developed and prototype products, such as IoT platforms, been introduced. However, each of these architectures and products apply their very own interpretations of an IoT architecture and its individual components so that IoT is currently more an Intranet of Things than an Internet of Things (Zorzi et al. 2010). Thus, this thesis aims to develop a common understanding of the elements forming an IoT architecture and provide high-level specifications in the form of a Holistic IoT Architecture Framework.
Design Science Research (DSR) is used in this thesis to develop the architecture framework based on the pertinent literature. The development of the Holistic IoT Architecture Framework includes the identification of two new IoT Architecture Perspectives that became apparent during the analysis of the IoT architecture proposals identified in the extant literature. While applying these novel perspectives, the need for a new component for the architecture framework, which was merely implicitly mentioned in the literature, became obvious as well. The components of various IoT architecture proposals as well as the novel component, the Thing Management System, were combined, consolidated and related to each other to develop the Holistic IoT Architecture Framework. Subsequently, it was shown that the specifications of the architecture framework are suitable to guide the implementation of a prototype.
This contribution provides a common understanding of the basic building blocks, actors and relations of an IoT architecture.
This dissertation will discuss the theories of exponents of the philosophy of dialogue. Through that it shall establish the basis to reflect entrepreneurial leadership action. The goal is to find an approach for the development of a dialogical leadership culture.
The empirical part shall examine on what basis, in correlation with a dialogical leadership style, subjective assumptions are made by managers in their leadership action who work in inpatient nursing services. Furthermore, it shall address the question of how those subjective assumptions can be considered and utilized towards establishing future dialogically oriented leadership cultures and the development of coinciding management personnel.
It shall also debate the question to what extent the philosophy of dialogue includes theoretical concepts which can be used to describe a leadership culture. The intellectual approach of Martin Bubers is especially taken into consideration.
Based on these theoretical grounds, the attempt shall be made to develop the basic intention of a dialogical leadership culture which will appropriately justify a didactical concept for the development of management personnel in nursing services.
Grundwasser ist eine lebenswichtige Ressource und gleichzeitig ein thermisch stabiler Lebensraum mit einer außergewöhnlichen Fauna. Aufgrund der Klimageschichte der letzten ca. 1,8 Millionen Jahre in Mitteleuropa war die Ausgangshypothese, dass die meisten Grundwasserarten an Temperaturen unterhalb von 14 °C angepasst sind und sich Temperaturerhöhungen daher negativ auf die Grundwasserfauna auswirken.
Um die Folgen einer Klimaerwärmung in situ beurteilen zu können, wurden anthropogen erwärmte Grundwässer als Modelle herangezogen. In ersten Teil dieser Arbeit wurden die Crustaceagemeinschaften natürlich temperierter und anthropogen erwärmter Standorte untersucht. Dazu wurden insgesamt 70 Grundwassermessstellen im Oberrheingraben über ein Jahr (2011 bis 2012) sechsmal beprobt. Ergänzend zu diesem synökologischen Ansatz wurde in einem zweiten Teil die Temperaturpräferenz ausgewählter Arten überprüft. Für diese autökologische Betrachtung wurde ein deutschlandweiter Datensatz herangezogen.
Die ausgewählten Untersuchungsgebiete haben sich als geeignete Modelle für die prognostizierten Temperaturerhöhungen herausgestellt. Die Temperatur erwies sich als einer der wichtigsten Parameter für die Crustaceagemeinschaften. Erwärmungen beeinflussen die Zusammensetzung der Gemeinschaften und die Diversität. Dabei zeigte sich, dass es artspezifisch unterschiedliche Temperaturpräferenzen gibt. Einige vermutlich weniger streng stygobionte Arten scheinen höhere Temperaturen zu tolerieren. Der Großteil der stygobionten Grundwasserarten bevorzugt allerdings Temperaturen unterhalb von 14 °C, wobei wenige Arten als „extrem kalt¬steno-therm“ einzustufen sind. Diese Arten wurden an Standorten nachgewiesen, die aufgrund der hydrologischen Verhältnisse relativ kühl sind und der Fauna auch zukünftig als kalte Refugien Schutz bieten könnten. Einer dieser Standorte ist aufgrund seiner Artenvielalt als „Hot Spot“ einzustufen. Die Ergebnisse legen nahe, dass vor allem kaltstenotherme Arten durch eine Klimaerwärmung und anthropogene Wärmeeinträge gefährdet sind.
Die Untersuchung zeigt, dass Grundwasserlebensräume vor Temperaturerhöhungen zu bewahren sind. Lokale anthropogene Wärmeeinträge sollten keine dauerhafte und großflächige Grundwassererwärmung über 14 °C zur Folge haben. Thermische Ein-träge sollten überwacht und bewertet werden. Es wird empfohlen, die bestehenden rechtlichen Rahmenbedingungen den ökologischen Erfordernissen anzupassen.
This thesis explores different approaches for the acceleration of raytracing calculations on the graphics processing unit (GPU). For that a voxel grid is used and extended by the linespace data structure. The linespace consists of direction based shafts and stores the objects located in those shafts in a candidate list. Different methods for the sorting and traversal of the linespace are presented and evaluated. The shown methods cannot provide a speed up of the frame rate without resulting in a loss of image quality.
World’s ecosystems are under great pressure satisfying anthropogenic demands, with freshwaters being of central importance. The Millennium Ecosystem Assessment has identified anthropogenic land use and associated stressors as main drivers in jeopardizing stream ecosystem functions and the
biodiversity supported by freshwaters. Adverse effects on the biodiversity of freshwater organisms, such as macroinvertebrates, may propagate to fundamental ecosystem functions, such as organic matter breakdown (OMB) with potentially severe consequences for ecosystem services. In order to adequately protect and preserve freshwater ecosystems, investigations regarding potential and observed as well as direct and indirect effects of anthropogenic land use and associated stressors (e.g. nutrients, pesticides or heavy metals) on ecosystem functioning and stream biodiversity are needed. While greater species diversity most likely benefits ecosystem functions, the direction and magnitude of changes in ecosystem functioning depends primarily on species functional traits. In this context, the functional diversity of stream organisms has been suggested to be a more suitable predictor of changes in ecosystem functions than taxonomic diversity.
The thesis aims at investigating effects of anthropogenic land use on (i) three ecosystem functions by anthropogenic toxicants to identify effect thresholds (chapter 2), (ii) the organic matter breakdown by three land use categories to identify effects on the functional level (chapter 3) and (iii)on the stream community along an established land-use gradient to identify effects on the community level.
In chapter 2, I reviewed the literature regarding pesticide and heavy metal effects on OMB, primary production and community respiration. From each reviewed study that met inclusion criteria, the toxicant concentration resulting in a reduction of at least 20% in an ecosystem function was standardized based on laboratory toxicity data. Effect thresholds were based on the relationship between ecosystem functions and standardized concentration-effect relationships. The analysis revealed that more than one third of pesticide observations indicated reductions in ecosystem functions at concentrations that are assumed being protective in regulation. However, high variation within and between studies hampered the derivation of a concentration-effect relationship and thus effect thresholds.
In chapter 3, I conducted a field study to determine the microbial and invertebrate-mediated OMB by deploying fine and coarse mesh leaf bags in streams with forested, agricultural, vinicultural
and urban riparian land use. Additionally, physicochemical, geographical and habitat parameters were monitored to explain potential differences in OMB among land use types and sites. Regarding results, only microbial OMB differed between land use types. The microbial OMB showed a negative relationship with pH while the invertebrate-mediated OMB was positively related to tree cover. OMB responded to stressor gradients rather than directly to land use.
In chapter 4, macroinvertebrates were sampled in concert with leaf bag deployment and after species identification (i) the taxonomic diversity in terms of Simpson diversity and total taxonomic
richness (TTR) and (ii) the functional diversity in terms of bio-ecological traits and Rao’s quadratic entropy was determined for each community. Additionally, a land-use gradient was established and the response of the taxonomic and functional diversity of invertebrate communities along this gradient was investigated to examine whether these two metrics of biodiversity are predictive for the rate of OMB. Neither bio-ecological traits nor the functional diversity showed a significant relationship with
OMB. Although, TTR decreased with increasing anthropogenic stress and also the community structure and 26 % of bio-ecological traits were significantly related to the stress gradient, any of these shifts propagated to OMB.
Our results show that the complexity of real-world situations in freshwater ecosystems impedes the effect assessment of chemicals and land use for functional endpoints, and consequently our potential to predict changes. We conclude that current safety factors used in chemical risk assessment may not be sufficient for pesticides to protect functional endpoints. Furthermore, simplifying real-world stressor gradients into few land use categories was unsuitable to predict and quantify losses in OMB. Thus, the monitoring of specific stressors may be more relevant than crude land use categories to detect effects on ecosystem functions. This may, however, limit the large scale assessment of the status of OMB. Finally, despite several functional changes in the communities the functional diversity over several trait modalities remained similar. Neither taxonomic nor functional diversity were suitable predictors of OMB. Thus, when understanding anthropogenic impacts on the linkage between biodiversity and ecosystem functioning is of main interest, focusing on diversity metrics that are clearly linked to the stressor in question (Jackson et al. 2016) or integrating taxonomic and functional metrics (Mondy et al., 2012) might enhance our predictive capacity.
Agricultural land-use may lead to brief pulse exposures of pesticides in edge-of-field streams, potentially resulting in adverse effects on aquatic macrophytes, invertebrates and ecosystem functions. The higher tier risk assessment is mainly based on pond mesocosms which are not designed to mimic stream-typical conditions. Relatively little is known on exposure and effect assessment using stream mesocosms.
Thus the present thesis evaluates the appliacability of the stream mesocosms to mimic stream-typical pulse exposures, to assess resulting effects on flora and fauna and to evaluate aquatic-terrestrial food web coupling. The first objective was to mimic stream-typical pulse exposure scenarios with different durations (≤ 1 to ≥ 24 hours). These exposure scenarios established using a fluorescence tracer were the methodological basis for the effect assessment of an herbicide and an insecticide. In order to evaluate the applicability of stream mesocosms for regulatory purposes, the second objective was to assess effects on two aquatic macrophytes following a 24-h pulse exposure with the herbicide iofensulfuron-sodium (1, 3, 10 and 30 µg/L; n = 3). Growth inhibition of up to 66 and 45% was observed for the total shoot length of Myriophyllum spicatum and Elodea canadensis, respectively. Recovery of this endpoint could be demonstrated within 42 days for both macrophytes. The third objective was to assess effects on structural and functional endpoints following a 6-h pulse exposure of the pyrethroid ether etofenprox (0.05, 0.5 and 5 µg/L; n = 4). The most sensitive structural (abundance of Cloeon simile) and functional (feeding rates of Asellus aquaticus) endpoint revealed significant effects at 0.05 µg/L etofenprox. This concentration was below field-measured etofenprox concentrations and thus suggests that pulse exposures adversely affect invertebrate populations and ecosystem functions in streams. Such pollutions of streams may also result in decreased emergence of aquatic insects and potentially lead to an insect-mediated transfer of pollutants to adjacent food webs. Test systems capable to assess aquatic-terrestrial effects are not yet integrated in mesocosm approaches but might be of interest for substances with bioaccumulation potential. Here, the fourth part provides an aquatic-terrestrial model ecosystem capable to assess cross-ecosystem effects. Information on the riparian food web such as the contribution of aquatic (up to 71%) and terrestrial (up to 29%) insect prey to the diet of the riparian spider Tetragnatha extensa was assessed via stable isotope ratios (δ13C and δ15N). Thus, the present thesis provides the methodological basis to assess aquatic-terrestrial pollutant transfer and effects on the riparian food web.
Overall the results of this thesis indicate, that stream mesocosms can be used to mimic stream-typical pulse exposures of pesticides, to assess resulting effects on macrophytes and invertebrates within prospective environmental risk assessment (ERA) and to evaluate changes in riparian food webs.
Since software influences nearly every aspect of everyday life, the security of software systems is more important than ever before. The evaluation of the security of a software system still poses a significant challenge in practice, mostly due to the lack of metrics, which can map the security properties of source code onto numeric values. It is a common assumption, that the occurrence of security vulnerabilities and the quality of the software design stand in direct correlation, but there is currently no clear evidence to support this. A proof of an existing correlation could help to optimize the measurements of program security, making it possible to apply quality measurements to evaluate it. For this purpose, this work evaluates fifty open-source android applications, using three security and seven quality metrics. It also considers the correlations between the metrics. The quality metrics range from simple code metrics to high-level metrics such as object-oriented anti-patterns, which together provide a comprehensive picture of the quality. Two visibility metrics, along with a metric that computes the minimal permission request for mobile applications, were selected to illustrate the security. Using the evaluation projects, it was found that there is a clear correlation between most quality metrics. By contrast, no significant correlations were found using the security metrics. This work discusses the correlations and their causes as well as further recommendations based on the findings.
Die vorliegende Doktorarbeit hatte zum Ziel zu prüfen, ob Emulsionspolymere auf Acrylatbasis als neuartige Photokatalysatoren bzw. Katalysatoren genutzt werden können.
Auf Grund der Beschaffenheit und der Eigenschaften von Emulsionspolymeren ist davon auszugehen, dass die Nutzung selbiger als Katalysatoren eine neue Art einer chemischen Katalyse ermöglicht. So sollen die Vorteile der heterogenen und homogenen Katalyse vereint und die jeweiligen Nachteile minimiert werden. Als besonders erfolgversprechend hat sich während der praktischen Arbeit die Nutzung von Emulsionspolymeren als Photokatalysatoren herausgestellt.
Die Anbindung der photokatalytisch aktiven Moleküle an/in den Polymerstrang soll kovalent erfolgen. Deshalb war ein erstes Teilziel dieser Arbeit prototypische Katalysatormoleküle zu synthetisieren, die über einen Acrylat-Substituenten verfügen, der in einer radikalischen Polymerisationsreaktion reagieren kann. Als Photokatalysatoren wurden Ruthenium- Polypyridin-Komplexe ausgewählt, die sowohl für eine inter- als auch intramolekulare Photokatalyse zur Herstellung von Wasserstoff aus Wasser geeignet sind. Für organokatalytische Zwecke wurde ein L-Prolin-Derivat synthetisiert, welches jedoch nicht auf seine Polymerisierbarkeit getestet wurde.
In einem ersten Schritt wurden die prototypischen 2,2’-Bipyridin-Liganden synthetisiert. Dabei konnte eine verbesserte Synthesemethode für 4-Brom-2,2’-bipyridin ausgearbeitet werden. Die Funktionalisierung erfolgte letztendlich durch eine Horner-Wadsworth-Emmons-Reaktion, die anschließend an eine Eintopfsynthese zur Darstellung von 4-Formyl-2,2’-biypridin erfolgte. Die prototypischen Photokatalysatoren zeigten mäßige Erfolge (TON: 37-136, 6h, 10% H2O, 470 nm) in Bezug auf die photokatalytische Wasserstoffproduktion, sodass an dieser Stelle eine Verbesserung der entsprechenden katalytischen Systeme erfolgen sollte.
Die Polymerisationsreaktion konnte für zwei intermolekulare Photokatalysatoren und zwei intramolekulare Photokatalysatoren durchgeführt werden. Dabei fiel auf, dass die intermolekularen Photokatalysatoren besser polymerisieren als die intramolekularen Photokatalysatoren. Es wird angenommen, dass dies mit der Löslichkeit der Substanzen im Monomer Ethylmethacrylat zusammen hängt.
Die photokatalytisch funktionalisierten Emulsionspolymere zeigten eine ähnliche photokatalytische Aktivität (TON: 9-101, 6h, 10% H2O, 470 nm) wie die jeweiligen Ausgangsstoffe selbst. Es konnte jedoch bewiesen werden, dass Emulsionspolymere als Photokatalysatoren genutzt werden können, wenn auch noch weitere Arbeiten zur Optimierung der Systeme nötig sind.
The market for virtual reality is rapidly evolving regarding its hardware components. Further applications are the result of this progress. In addition to the gaming market virtual reality offers further possibilities and advantages in research. That way this technology provides the investigation of perceptual phenomena. Therefore the present thesis aimed to examine the induced roelofs effect in a virtual environment and in reality in front of a computer screen. The roelofs effect describes a misperception that occurs if a persons midline and a target surrounding frame are offset, which results in a false localisation of the object. Thus the present study provides insight into the influence of a computer screen regarding this effect. Moreover, conclusions concerning the suitability of virtual reality in perceptual research are drawn. The results obtained by the virtual reality indicated a greater degree of perceptual distortion. Therefore the fixed frame of the computer screen can be assumed as an additional orientation.
An assistance system has been developed for the purpuse of supporting the surgeon during the repositioning phase of intramedullary nailing of femural shaft fractures. As a basic principle the high forces generated by femural muscles and ligaments are taken by a linear sledge and a threaded rod. In order to move bone fragments directly Schanz screws are used as bone-machine interface. Two more Schanz screws are used for fine tuning orientation and position of the fragments according to the well known Joystick technique. The screws are fixed to two articulated arms, one passive and one fully robotic with manipulator. Thanks to the serial kinematic configuration of the system only minmal space of the surgeons working area gets occupied. Running a realtime operating system, the central control unit consits could be implemented as an embedded system comprising of a ARM Cortex-M0 microcontroller at it’s heart. This enables realtime computation and motor control of each joints value of the robotic arm using inverse kinematics. As inverse kinematics solver the iterative FABRIK algorithm was chosen. Serving as innovative and single user interface for the surgeon an optical force-torque sensor is used. The robotic arm always follows the surgeons motion when interacting with the sensor. Using the proposed demonstrator system a positioning resulution of <0,1mm could be accomplished. Thus by using the proposed solution during intramedullary nailing of femural shaft fractures a tremendous gain in positioning precision of bone fragments can be achieved. Furthermore a massive reduction of x-ray exposition of the surgeon is possible when applying the proposed approach. Also this approach enables the chance of cost reduction of femural fracture therapy due to reduction of needed time and staff.
Augmented reality is being present for many years. Through progress in technology smaller augmented reality glasses became possible. These new technologies allow many new ways of interaction and usage of augmented reality.
This thesis is about the Microsoft HoloLens and its possiblities for consumers and industry. In the context of this thesis a new interactive and augmented application to measure the possiblities and limitations of the Microsoft HoloLens has been developed. The scene is an assembly szenario with a step by step instruction of building with Lego bricks. The evaluation showed that the HoloLens can already be used to assist in assembling scenarios and offers some advantages over other methods, although the glasses still have some flaws.
Die deutsche Holzhausbranche wächst seit Jahren, allerdings beschäftigen sich die Unternehmen nicht strategisch mit dem Thema Marketing. Diese Dissertation bildet durch qualitative und quantitative Bewohnerbefragungen die Basis für die Entwicklung eines strategischen Marketingansatzes im Holzhausbereich.
E-Learning Anwendungen sind heutzutage im Trend. Jedoch nicht nur aus diesem Grund sind sie vom großen Interesse. Im Vordergrund steht ihr didaktisches Konzept. Heutzutage ist es technisch möglich, die Teilnehmer interaktiv in einen
E- Learning Kurs einzubinden. Die Lernschritte können durch die Anwendung kontrolliert werden. Im Gegensatz zu einer Vorlesung, kann die Theorie direkt mit der Praxis verknüpft werden. Das Ziel der Arbeit ist die Erstellung eines Konzeptes und die Entwicklung eines Prototypen einer interaktiven Entwicklungsumgebung von Java für Programmieranfänger. In dieser Arbeit wurden aktuelle E-Learning Plattformen zu Java analysiert. Aus den gewonnen Erkenntnissen wurde ein Konzept für eine E-Learningplattform entwickelt. Dieses Konzept wurde erfolgreich als Prototyp implementiert. Für die Implementation wurden bewährte Technologien, wie das Django-Framework und das Javascript-Framework Vue.js eingesetzt. Der Kurs wurde von neun Teilnehmern getestet. Zusätzlich wurde eine Umfrage zu der Kursanwendung durchgeführt. Das Testergebnis bestätigt, dass die Teilnehmer den Kurs bestanden haben.
This thesis presents the use of a local linespace data structure, which is designed and implemented on the basis of an existing GPU-based raytra- cer with a global linespace data structure. For each scene object, an N-tree is generated whose nodes each have a linespace. This saves informations about existing geometry in its shafts. A shaft represents a volume between two faces on the outside of the node. This allows a faster skipping of em- pty spaces during raytracing. Identical objects can access already calcula- ted linespaces, which can reduce the memory requirement by up to 94.13% and the initialization time of the datastructure by up to 97.15%. Due to the local access possibilities dynamic scenes can be visualized. An increase in quality can also be observed.
For a comprehensive understanding of evolutionary processes and for providing reliable prognoses about the future consequences of environmental change, it is essential to reveal the genetic basis underlying adaptive responses. The importance of this goal increases in light of ongoing climate change, which confronts organisms worldwide with new selection pressures and requires rapid evolutionary change to avoid local extinction. Thereby, freshwater ectotherms like daphnids are particularly threatened. Unraveling the genetic basis of local adaptation is complicated by the interplay of forces affecting patterns of genetic divergence among populations. Due to their key position in freshwater communities, cyclic parthenogenetic mode of reproduction and resting propagules (which form biological archives), daphnids are particularly suited for this purpose.
The aim of this thesis was to assess the impact of local thermal selection on the Daphnia longispina complex and to reveal the underlying genetic loci. Therefore, I compared genetic differentiation among populations containing Daphnia galeata, Daphnia longispina and their interspecific hybrids across time, space, and species boundaries. I revealed strongly contrasting patterns of genetic differentiation between selectively neutral and functional candidate gene markers, between the two species, and among samples from different lakes, suggesting (together with a correlation with habitat temperatures) local thermal selection acting on candidate gene TRY5F and indicating adaptive introgression. To reveal the candidate genes’ impact on fitness, I performed association analyses among data on genotypes and phenotypic traits of D. galeata clones from seven populations. The tests revealed a general temperature effect as well as inter-population differences in phenotypic traits and imply a possible contribution of the candidate genes to life-history traits. Finally, utilizing a combined population transcriptomic and reverse ecology approach, I introduced a methodology with a wide range of applications in evolutionary biology and revealed that local thermal selection was probably a minor force in shaping sequence and gene expression divergence among four D. galeata populations, but contributed to sequence divergence among two populations. I identified many transcripts possibly under selection or contributing strongly to population divergence, a large amount thereof putatively under local thermal selection, and showed that genetic and gene expression variation is not depleted specifically in temperature-related candidate genes.
In conclusion, I detected signs of local adaptation in the D. longispina complex across space, time, and species barriers. Populations and species remained genetically divergent, although increased gene flow possibly contributed, together with genotypes recruited from the resting egg bank, to the maintenance of standing genetic variation. Further work is required to accurately determine the influence of introgression and the effects of candidate genes on individual fitness. While I found no evidence suggesting a response to intense local thermal selection, the high resilience and adaptive potential regarding environmental change I observed suggest positive future prospects for the populations of the D. longispina complex. However, overall, due to the continuing environmental degradation, daphnids and other aquatic invertebrates remain vulnerable and threatened.
Skalierbarkeit und garantierte Ausliererung sind essentielle Eigenschaften eines jeden Routingalgorithmus. Beides bietet bei drahtlosen Ad-hoc Netzwerken die Kombination aus Greedy- und Face- Routing, sofern ein planarer Graph zur Verfügung steht. Doch gerade die fehlerfreie Planarisierung bereitet bei realistischen Netzwerken Schwierigkeiten. Daher soll mit dieser Arbeit die Frage beantwortet werden, zu welcher Fehlerrate es führt, wenn der Graph lediglich mit lokalen Methoden teilplanarisiert wird. Dazu wurde eine Simulationsumgebung geschaffen, um unter Anwendung des Log-Normal-Shadowing-Modells zufällige Konnektivitätsgraphen zu generieren. Diese wurden anschließend durch zwei unterschiedliche, lokale Strategien teilplanarisiert. Es wurden neun verschiedene Settings definiert, die sich aus drei unterschiedlichen Graphendichten und drei unterschiedlichen Werten für den Sigmaparameter des Log-Normal-Shadowing-Modells ergeben. Für jedes Setting wurde in 2000 Simulationsdurchläufen das Verhalten von Greedy-, Face- und kombiniertem Greedy-Face-Routing untersucht und ausgewertet. Zum Abschluss wurden die Ergebnisse dieser Simulation bewertet und diskutiert.
Der Fachbereich 4 (Informatik) besteht aus fünfundzwanzig Arbeitsgruppen unter der Leitung von Professorinnen und Professoren, die für die Forschung und Lehre in sechs Instituten zusammenarbeiten.
In jedem Jahresbericht stellen sich die Arbeitsgruppen nach einem einheitlichen Muster dar, welche personelle Zusammensetzung sie haben, welche Projekte in den Berichtszeitraum fallen und welche wissenschaftlichen Leistungen erbracht wurden. In den folgenden Kapiteln werden einzelne Parameter aufgeführt, die den Fachbereich in quantitativer Hinsicht, was Drittmitteleinwerbungen, Abdeckung der Lehre, Absolventen oder Veröffentlichungen angeht, beschreiben.
Der Fachbereich 4 (Informatik) besteht aus fünfundzwanzig Arbeitsgruppen unter der Leitung von Professorinnen und Professoren, die für die Forschung und Lehre in sechs Instituten zusammenarbeiten.
In jedem Jahresbericht stellen sich die Arbeitsgruppen nach einem einheitlichen Muster dar, welche personelle Zusammensetzung sie haben, welche Projekte in den Berichtszeitraum fallen und welche wissenschaftlichen Leistungen erbracht wurden. In den folgenden Kapiteln werden einzelne Parameter aufgeführt, die den Fachbereich in quantitativer Hinsicht, was Drittmitteleinwerbungen, Abdeckung der Lehre, Absolventen oder Veröffentlichungen angeht, beschreiben.
Gefährdete Weltmacht USA
(2017)
Aims and findings of the dissertation
The completed research uses holistic, politological and historical approaches to present how, during the studied period of the administrations of Clinton to Obama, the liberal, rule-based world order system is gradually supplemented and replaced by a system of realist imposition of vital interests that have short-term effects, preferring military means combined with continuous military optimisation. This also explains a continuity between the leading-power policy of administrations in this study (1993-2017) and the subsequent period of the “transactional leadership of Trump”(1), with its recognizable, far-reaching effects of aiming to reduce idealistic Grand Strategy elements and measures of a benevolent order by passing on costs to and reducing the benefits of European NATO allies. The results of this dissertation, such as the increasingly evident dissolution of a multilateral fundamental order, therefore indicate that Trump’s foreign and security policy to date should be regarded as a clearly noticeable crisis symptom, rather than the cause of a decline in the world order established after 1945. This decline is synonymous with the erosion of the transatlantically initiated bipolar “American system”. Its implementation was the result of the “lesson of two world wars”, based on modern concepts of order introduced by the Enlightenment and the founding criteria of the United States: thus its dissolution is also an indicator of the failure of contemporary criteria of order that thrive in the “American way of life”.
The cause of the described development is shown to be a constantly exacerbating overall threat, from Clinton to Obama, which is connected to the consistent erosion of US supremacy. Among other aspects, this is based on climate change effects postulated in 1979, which multiply the threat while coinciding with American peak production of fossil fuels and increased demand on resources in the context of dwindling raw material resources. Furthermore, during the period of this study, the “US conservative revolution”, which began in the 1980s, increasingly affected foreign and security policy, combining with a consolidation in the influence of corporations and lobby groups in fields such as policy implementation and new underlying conditions. They include the onset of digitisation, entailing a high consumption of resources, and a growing world population faced with specific demographic indicators. Additionally, the maintenance of the armaments sector, originally a result of bipolar development, as the economic basis of military supremacy and the slow decline of the Dollar hegemony since around 1973, should also be taken into account. Complex interaction between Grand Strategy implementation according to the premise of expanding US-American dominance under neoconservative and Christian Right-wing influences, as well as asymmetrical and reactivated conventional security threats and threat multipliers clearly indicate the linear development of the overall threat in the period between 1993 and 2017: in the context of Grand Strategy statements, above all the understanding of defence against this threat, of the latter’s multiplying factors and the market economy explains the following with respect to the US far-right in a complex interaction with the growth of transnational corporations, lobby groups, individuals(2), informal networks and state actors with respect to objects of threat and threat multipliers(3) in connection with the post-bipolar, global anchoring of US economic and consumer patterns: US adaptation of its reaction to this threat – while consolidating imperial presidency(4) and weakening the system of checks and balances – including its implications of a bipolar liberal order. In this way, the necessary continued leadership within NATO through the US-proposed NATO reform can be seen as an appropriate implementation of transformed threat-reaction measures and the legitimisation of systemic adaptation. It equally becomes clear that the established threat reaction measures only provide a short-term defence: instead, they enhance the asymmetric and conventional threat, as well as threat multipliers – by introducing arms races and breaking down arms control – thereby heightening the overall threat. The consequence is the consistently growing likelihood of a conflict of hitherto unimaginable proportions. At the same time, the urgent need to mobilise transatlantic cooperation with respect to supporting global cooperation between state and non-government actors is illustrated with respect to the roots of the threat and its deteriorating underlying conditions: each increase in the overall threat, the adapted US security policy and its continuation in NATO is connected to an erosion of rule-based underlying criteria during the studied period. This continuously and consistently undermines the basis of the above-stated, ever-increasingly important cooperation, to prevent or at least limit the successive erosion of the bipolar “American system” under future dystopias. The research results completely overturn the state of research to date, since for instance it is possible to show that, by means of NATO transformation findings, no transatlantic sharing of burdens on an equal footing and no NATO reform in accordance with its founding principles can be achieved. The same also applies to European opposition to the actual anchoring of NATO transformation positions(5), which is based on the erosion of the bipolar liberal order system and the maintenance of US advantages as well as the consolidation of particular interests they facilitate. Furthermore, it is apparent that a line of continuity in the threat-reaction measures from Clinton to Obama exists with varying external effects, along with an underlying pattern of “Battleship America” – as opposed to a multilaterally orientated foreign and security policy under Clinton, which merged into a unilateral, radical swing under G. W. Bush 43 following 9/11, but was reverted by the Obama administration. A comprehensive wealth of literature was used of the doctoral thesis, as reflected by the extensive bibliography: they firstly include diverse American and European publications, monographs and relevant secondary literature, including biographies, publications of various kinds of important political planning and implementation, as well as collected volumes and research articles from specialist journals on all fields of research and politological methodology and theory. The same applies to publications by leading European and American institutions, research centres and think tanks. Furthermore, this author used publications and documents by governments, foreign ministries, defence ministries, other government bodies and Nato.
Dissertation structure
This dissertation is divided into two volumes and one Appendix: Volume 1 discusses Focus 1, namely a process-tracing in the context of offensive neorealist positioning. Volume 2 presents Focus 2, which is based on the preceding focus in making a structured, focussed comparison in the context of defensive neorealist positioning. The Appendix volume contains further discussion of Chapter 1, Volume 1 with respect to the state of research, literature and sources, theoretical positioning and the choice of the region of study and selected European NATO partners. Furthermore, a historical chapter provides underlying information for process-tracing in Chapter 2, Volume 1, an index of images and abbreviations, and a bibliography.
The entire dissertation uses qualitative methods to focus on these two mutually supporting, building on each other, themes to investigate the following from a US-perspective: firstly the overriding US security-policy reaction to a new overall threat and secondly, its continuation combined with the opportunity of for enabling and legitimising it within and through NATO during the studied period from Clinton to Obama.
Based on the first part of this hypothesis, Focus 1 (Volume 1) establishes a connection between, on the one hand, maintaining the bipolar Grand Strategy target of consolidating the USA as a leading, regulating power, bipolar foreign-policy Grand Strategy indicators and a new overall threat that is developing in a complex way, and, on the other, the necessity of its continued leadership within NATO and the required NATO transformation according to US-proposed NATO transformation positions.
Focus 2 (Volume 2) is based on the second part of the hypothesis, investigating the transatlantic negotiation process to establish these US-proposed NATO transformation positions: in this context, Volume 2 investigates whether the attempt to actually secure and consolidate such US supremacy was unsuccessful in the face of resistance from selected European NATO partners, namely France, Germany and the United Kingdom.
The overall result shows that due to a complex, developing, linear increase in the overall threat, the chance for the USA to consolidate its status as a leading power is steadily diminishing. This must be compensated by adapting US security policy. The resulting American security-policy realignment based on the initiated “revolution in military affairs” in turn modifies the indicators of bipolar collective security guarantees. Everything is enabled and legitimised by means of actually securing US NATO-transformation positions. The actual implementation of such NATO transformation – representing the consistent adaptation of US security policy – enables a mission-orientated, rapid response, flexible, global security projection. It also creates conditions for “alliances of choice” within NATO. Furthermore, the modification of a “bipolar NATO” exacerbates the erosion of key achievements of civilisation as a result of adapted US security policy, as well as undermining the tasks of bipolar collective security guarantees through diminished benefits to European NATO partners.
The actual anchoring of NATO transformation positions is achieved by reactivating the conventional threat in the context of the Ukraine crisis of 2014 and the extension of NATO partnership rings on a global level, without providing them with NATO membership status, thus avoiding globalisation in a mutual defence case. The German and French resistance is particularly intensive through the involvement of European founder states, while the formation of a European leadership triumvirate consisting of France, Germany and the United Kingdom does not take place.
Moreover, a relevant investigation of causes particularly shows that despite constant mutually supporting US security reaction measures with varying international effects and actual continued leadership within NATO, the overall threat is not receding: this leads to a constant increase in the overall threat, a loss of influence of state actors, the diffusion and concentration of power and the increased probability of reactive conventional, nuclear, cyber and ecological destruction scenarios. On this basis, the consequence is an increasingly comprehensive and rapidly responding precision defence combined with growing securitization to compensate for the ongoing containment of US supremacy. This developing process steadily diminishes the reach and power of a liberal, rule-based, bipolar “American system” and the establishment of “idealistic, liberal” elements of US-Grand Strategy. This entails a further reduction in benefits for European NATO allies and increasing US cost-cutting demands – based on the successive NATO transformation positions that build on each other and Obama’s “smart power”(6) during the period studied in this dissertation. Thus the chance is receding of developing the post-bipolar, globally adopted American way of life with individual national character, which is regarded as “non-negotiable”: for instance its articulation is expressed through increasing right-wing populism, the election of outsider-candidates, the dissolution of traditional party systems, isolationist tendencies combined with burgeoning ethnic, regional movements, the rejection of supranationalism, and religious fundamentalism. At the same time, the ongoing erosion of global public goods is apparent.
This all paves the way to limiting the benevolent American regulating power and state actors’ leverage – and therefore to a return to classic power politics in the context of a resulting diffusion and concentration of power. In view of the urgency of a long-term containment of asymmetrical or conventional threats to security, or aspects that exacerbate such threats or clusters thereof, as well as underlying global conditions, this undermines the ability to achieve the following: to achieve transatlantic cooperation by broadening the range of levels and actors in the spirit of proactive and expanded, networked security to achieve according global cooperation with respect to containing the root causes of threats.
Overall, this research work reveals how and why the anticipated “peace dividend” and the notion of an “age of hope”, as postulated by President Clinton, were hardly perceptible during the period of study between 1993 and 2017.
Notes
(1) Cf. Braml, Josef (2018), Trumps transaktionaler Transatlantizismus, in: Jäger, Thomas (Hrsg.), Zeitschrift für Außen- und Sicherheitspolitik, Oktober 2018, Volume 11, Ausgabe 4, S. 439-448, Wiesbaden.
(2) Cf. National Intelligence Council (Ed.) (2012), Global Trends 2013: Alternative Worlds (NIC 2012-001), https://publicintelligence.net/global-trends-2030/, last accessed: 12.04.19. See also the “international financial leadership, self-selected at Davos” cit. McCoy, Alfred W. (2017), In the Shadows of the American Century. The Rise and Decline of US Global Power, Chicago.
(3) In 1990, the threat-enhancing nature of climate change was already postulated with respect to asymmetric objects of threat as well as conventional and complex clusters: “Over the next half century, the global average temperature may increase by approximately 4 degrees C. (…) All nations will be affected. (…) How much time will there be to confirm the amount of change and then to act? (…) However, many believe that we will have waited too long to avoid major dislocation, hardship and conflict – on a scale not as yet seen by man“. Cf. Kelley, Terry P. (1990), Global Climate Change. Implications For The United States Navy (The United States Naval War College, Newport, RI), http://documents.theblackvault.com/documents/weather/climatechange/globalclimatechange-navy.pdf, last accessed: 30.03.19. Cf. Mazo, Jeffrey (2010), Climate Conflict. How global warming threatens security and what to do about it, London, Abingdon.
This supports the thesis of a developing, constant overall threat during the period between 1993 and 2017.
(4) Cf. Schlesinger, Arthur M., Jr. (1973), The Imperial Presidency, Boston.
(5) In this dissertation, the proposed US positions on NATO adaptation, the NATO Response Force and the Global Partnership Initiative are described as “NATO transformation positions”: Their actual establishment was connected to a NATO transformation with the consistent continuation of adapted US security policy.
(6) Cf. Nossel, Suzanne (2004), Smart Power. Reclaiming Liberal Internationalism, http://www.democracyarsenal.org/SmartPowerFA.pdf, last accessed: 26.08.17, Nye, Joseph S. Jr. (2011), The Future of Power, New York, Nye, Joseph S. Jr. (2011), Macht im 21sten Jahrhundert. Politische Strategien für ein neues Zeitalter, München, Rodham Clinton, Hillary (2010), Leading Through Civilan Power. Redefining American Diplomacy and Development, in: Foreign Affairs, November/December 2010, Vol. 89, No.6, S. 13-24.
This thesis presents a novel technique in computer graphics to simulate realtime
global illumination using path tracing. Path tracing is done with compute shaders on the graphics card (GPU) to perform rendering in a highly parallelized manner. To improve the overall performance of tracing rays, the Line Space is used as an acceleration data structure in different variations, resulting in better
empty space skipping. The Line Space saves scene information based on a previous voxelization in direction-dependent shafts and is generated and traversed on the GPU. With this procedure, indirect lighting and soft shadows can be computed in a physically correct way. Furthermore, using the Line Space, path tracing can be performed mostly independent of the complexity of the scene geometry with over 100 frames per second, which is truly real-time and much faster than using a comparable voxel grid. The image quality is not affected negatively by this technique and the shadow quality is in most cases much better compared to shadow-mapping.
This thesis deals with the exploration of different interaction possibilities
for three-dimensional, virtual objects in a real environment. The focus lies
especially on interaction possibilities from new AR-technologies.
A playful prototype of an application for Microsofts HoloLens will be
designed and implemented. The prototype consists of three parts. The first
part is the scan-process of the real environment of the user. In the second
part the user can augment the real environment with three-dimensional,
virtual objects. In the third part the user is supposed to navigate a virtual
avatar through the real environment.
The interaction possibilities of the HoloLens like Gaze, Gesture and VoiceInput
will be evaluated in the following categories menu navigation, positioning
of three-dimensional objects in a real environment and controlling an
avatar.
Die Erzählung Der Sandmann ist seit nun mehr zwei Jahrhunderten Bestandteil der deutschen Literaturhistorie. Als eines der bekanntesten Werke E.T.A. Hoffmanns hat es im Laufe der Zeit darüber hinaus seinen Platz unter anderem in der Oper, im Hörspiel und auch im Film gefunden. An dieser Stelle setzt die hier vorgelegte Arbeit an und untersucht Hoffmanns Novelle sowie eine filmische Umsetzung in Hinblick auf ihre (formalen und inhaltlichen) Eigenheiten. Das Ziel dieser Arbeit ist dabei die Beantwortung der Frage, ob die behandelten Motive als Leitmotive bezeichnet werden können, welche formalen Eigenheiten sie möglicherweise unterstützen und wie sich die Charakteristik der Erzählung inklusive der Motive für einen Film (beziehungsweise für ein Drehbuch) adaptieren lässt.
Identifikation und Analyse von Konfigurationen zwischenbetrieblicher Integration in der Möbelbranche
(2017)
In der Möbelbranche in Deutschland existieren seit mehreren Jahren branchenweite Bemühungen, zwischenbetriebliche Kooperationen durch organisatorische und technische Lösungen (z.B. Standardisierung von Austauschformaten) zu unterstützen. In einigen Branchensegmenten (vor allem Küche und Polster) konnten sich Infrastrukturen zur Integration etablieren, die von vielen Branchenteilnehmern akzeptiert und genutzt werden. Trotz dieser Entwicklung sind in den genannten Branchensegmenten überraschende Phänomene in jüngerer Vergangenheit zu beobachten: Mängel in der Prozessintegration zwischen Branchenakteuren, Unterschiede im Standardisierungsfortschritt zwischen den Branchensegmenten und die Entstehung unterschiedlicher Infrastrukturen zur zwischenbetrieblichen Integration. Bei näherer Betrachtung der beobachteten Phänomene offenbart sich ein hoch-komplexes Zusammenspiel der in der Möbelbranche agierenden Akteure auf drei unterschiedlichen Ebenen (institutionell, organisatorisch und technisch). Um die verantwortlichen Zusammenhänge zu verstehen, ist eine ganzheitliche Betrachtung relevanter Faktoren erforderlich. Dafür gibt es bislang nur wenige überzeugende Konzepte. Die Konfigurationsanalyse nach Lyytinen und Damsgaard betrachtet Unternehmensnetzwerke als Konfigurationen zwischenbetrieblicher Integration, die einem stabilen Muster von Kooperationsformen entsprechen. Sie ist insbesondere dafür geeignet, Unternehmensnetzwerke auf Branchenebene zu untersuchen. In der vorliegenden Arbeit wird die Konfigurationsanalyse mittels eines speziell dafür entwickelten bzw. angepassten Forschungsdesigns zum ersten Mal operationalisiert. Dazu wurden in 21 Interviews mit 19 Organisationen Daten zu Konfigurationen zwischenbetrieblicher Integration in zwei Branchensegmenten der Möbelbranche (Küche und Polster) in Deutschland erhoben, analysiert und Erklärungsansätze für die drei oben genannten Phänomene entwickelt. Die Ergebnisse zeigen, dass komplexe Konstellationen von Brancheneigenschaften die existierenden Konfigurationen begründen. Insgesamt wurden vier Konfigurationstypen (Mittler, Branche, Dyade und Triade) identifiziert, die in 17 konkreten Konfigurationen zum Einsatz kommen (Mittler (4-mal), Branche (5-mal), Dyade (6-mal) und Triade (2-mal)). Die Ursachen für die beobachteten Phänomene sind vielfältig. Insbesondere sind bestimmte branchenbezogene Charakteristika (u.a. Produkteigenschaften),der Wettbewerb zwischen Akteursklassen und zuletzt die wirtschaftliche Überlegenheit des Handels gegenüber den Herstellern ausschlaggebend. Der Standardisierungsfortschritt in den Branchensegmenten und die zugrunde liegenden Infrastrukturen sind vor allem von dem betriebswirtschaftlichen Nutzenpotenzial abhängig, das ihnen jeweils zugeschrieben wird. Die Prozessintegration hingegen benötigt eine zentral steuernde Instanz zur erfolgreichen IOIS-Diffusion.
In the last few years the Internet of things has gained increased attention from authors as well as companies due to its innovation potential. The rising interest in the Internet of Things has also affected the logistics, which currently suffers from the effects of the globalization and the ever-increasing competitive pressure. Thus, there are efforts to discover how the logistics can profit from the use of IoT concepts, ideas and technologies to help it overcome its challenges. This research study focuses on the identification of these efforts and the corresponding research for logistics processes. For that purpose the researcher explored current literature referring to this topic. The final outcome of this paper is a structured overview of the identified IoT use-cases, their corresponding technologies and devices and finally their affected stakeholders. Whether the expectations regarding the IoT implementation in logistics processes are met, how companies can profit from these use-cases and which problems potentially arise by using IoT devices and technologies in logistics are answered at the end of this paper.
The output of eye tracking Web usability studies can be visualized to the analysts as screenshots of the Web pages with their gaze data. However, the screenshot visualizations are found to be corrupted whenever there are recorded fixations on fixed Web page elements on different scroll positions. The gaze data are not gathered on their fixated fixed elements; rather they are scattered on their recorded scroll positions. This problem has raised our attention to find an approach to link gaze data to their intended fixed elements and gather them in one position on the screenshot. The approach builds upon the concept of creating the screenshot during the recording session, where images of the viewport are captured on visited scroll positions and lastly stitched into one Web page screenshot. Additionally, the fixed elements in the Web page are identified and linked to their fixations. For the evaluation, we compared the interpretation of our enhanced screenshot against the video visualization, which overcomes the problem. The results revealed that both visualizations equally deliver accurate interpretations. However, interpreting the visualizations of eye tracking Web usability studies using the enhanced screenshots outperforms the video visualizations in terms of speed and it requires less temporal demands from the interpreters.
Diese Arbeit kombiniert zwei Themengebiete, welche in unserer Gesellschaft und Wirtschaft immer präsenter und aktueller werden. Das erste Thema beinhaltet die Nachhaltigkeit, welche sich in dieser Arbeit in die drei Säulen Ökologie, Ökonomie und Soziales untergliedert. Die erste Säule, Ökologie, beschäftigt sich hauptsächlich mit der Bekämpfung von Umweltproblemen und dem nachhaltigen Erhalt der Natur. Der Bereich Ökonomie befasst sich damit, die Ressourcen nachhaltig zu nutzen, um ein langfristiges Erzielen von wirtschaftlichen Erträgen zu gewährleisten. Die letzte Säule hat den Zweck die Soziale Nachhaltigkeit zu fördern, indem der gesellschaftliche Zusammenhalt gesichert und die Chance auf Arbeit ermöglicht wird, um gleichzeitig für gute Arbeitsbedingungen zu sorgen. Alle drei Säulen sind daher auch für Unternehmen relevant und sollten von diesen stetig beachtet werden, um eine sogenannte unternehmerische Nachhaltigkeit umzusetzen. Zur Unterstützung dieser Umsetzung, soll hier das zweite Thema hinzugezogen werden, das sogenannte Internet of Things. Das Internet of Things gewinnt, wie auch das Thema Nachhaltigkeit, zunehmend an Bedeutung und bietet viele Vorteile zur Unterstützung nachhaltiger Unternehmen. Dabei sollen immer mehr Geräte zu intelligenten Geräten gewandelt werden um eine Integration in ein Informationsnetzwerk zu gewährleisten. Dort können gesammelte Daten sinnvoll analysiert und genutzt werden, wodurch viele Bereiche effizienter gestaltet und viele Handlungen erleichtert werden können.
Aufbauend auf diesen zwei Themengebiete werden, im weiteren Verlauf dieser Arbeit, IoT- Technologien vorgestellt, die der Unterstützung, in den Bereichen Ökologie, Ökonomie und Soziales, von Unternehmen dienen. Zu den aufgezeigten Technologien werden anschließend Beispiele präsentiert und, wenn vorhanden, auch die jeweiligen Anbieter.
Da eine Nutzung von IoT-Technologien nicht nur von Vorteil ist, sondern auch Herausforderungen mit sich bringt, werden diese abschließend aufgezeigt. Diesen Herausforderungen gilt es sich seitens der Unternehmen, der Gesellschaft und auch der Politik zu stellen, um eine effiziente Nutzung zu ermöglichen.
The Internet of Things (IoT) recently developed from the far-away vision of ubiquitous computing into very tangible endeavors in politics and economy, implemented in expensive preparedness programs. Experts predict considerable changes in business models that need to be addressed by organizations in order to respond to competition. Although there is a need to develop strategies for upcoming transformations, organizational change literature did not turn to the specific change related to the new technology yet. This work aims at investigating IoT-related organizational change by identifying and classifying different change types. It therefore combines the methodological approach of grounded theory with a discussion and classification of identified change informed by a structured literature review of organizational change literature. This includes a meta-analysis of case studies using a qualitative, exploratory coding approach to identify categories of organizational change related to the introduction of IoT. Furthermore a comparison of the identified categories to former technology-related change is provided using the example of Electronic Business (e-business), Enterprise Resource Planning (ERP) systems, and Customer Relationship Management (CRM) systems. As a main result, this work develops a comprehensive model of IoT-related business change. The model presents two main themes of change indicating that personal smart things will transform businesses by means of using more personal devices, suggesting and scheduling actions of their users, and trying to avoid hazards. At the same time, the availability of information in organizations will further increase to a state where information is available ubiquitously. This will ultimately enable accessing real time information about objects and persons anytime and from any place. As a secondary result, this work gives an overview on concepts of technology-related organizational change in academic literature.
The extensive literature in the data visualization field indicates that the process of creating efficient data visualizations requires the data designer to have a large set of skills from different fields (such as computer science, user experience, and business expertise). However, there is a lack of guidance about the visualization process itself. This thesis aims to investigate the different processes for creating data visualizations and develop an integrated framework to guide the process of creating data visualizations that enable the user to create more useful and usable data visualizations. Firstly, existing frameworks in the literature will be identified, analyzed and compared. During this analysis, eight views of the visualization process are developed. These views represent the set of activities which should be done in the visualization process. Then, a preliminary integrated framework is developed based on an analysis of these findings. This new integrated framework is tested in the field of Social Collaboration Analytics on an example from the UniConnect platform. Lastly, the integrated framework is refined and improved based on the results of testing with the help of diagrams, visualizations and textual description. The results show that the visualization process is not a waterfall type. It is the iterative methodology with the certain phases of work, demonstrating how to address the eight views with different levels of stakeholder involvement. The findings are the basis for a visualization process which can be used in future work to develop the fully functional methodology.
The presence of anthropogenic chemicals in the natural environment may impact both habitats and human use of natural resources. In particular the contamination of aquatic resources by organic compounds used as pharmaceuticals or household chemicals has become evident. The newly identified environmental pollutants, also known as micropollutants, often have i) unknown ecotoxicological impacts, ii) unknown partitioning mechanisms, e.g. sorption to sediments, and iii) limited regulation to control their emission. Furthermore, like any compound, micropollutants can be transformed while in the environmental matrix to unknown transformation products (TPs), which add to the number of unknown chemicals to consider and thus increase the complexity of risk management. Transformation is at the same time a natural mechanism for the removal of anthropogenic compounds, either by complete degradation (mineralisation) or to innocuous TPs. However, how transformation occurs in real-world conditions is still largely unknown. During the transport of micropollutants from household wastewater to surface water, a large amount of transformation can occur during wastewater treatment—specifically during biological nitrifying–denitrifying treatment processes. The thesis considers the systematic optimisation of laboratory investigative techniques, application of sensitive mass-spectrometry-based analysis techniques and the monitoring of full-scale wastewater treatment plants (WWTPs) to elucidate transformation processes of five known micropollutants.
The first of the five compounds investigated was the antibiotic trimethoprim. Incubation experiments were conducted at different analyte spike concentrations and different sludge to wastewater ratios. Using high-resolution mass spectrometry, a total of six TPs were identified from trimethoprim. The types of TPs formed was clearly influenced by the spike concentration. To the best of our knowledge, such impacts have not been previously described in the literature. Beginning from the lower spike concentration, a relatively stable final TP was formed (2,4-diaminopyrimidine-5-carboxylic acid, DAPC), which could account for almost all of the transformed trimethoprim quantity. The results were compared to the process in a reference reactor. Both by the detection of TPs (e.g., DAPC) and by modelling the removal kinetics, it could be concluded that only experimental results at the low spike concentrations mirrored the real reactor. The limits of using elevated spike concentrations in incubation experiments could thus be shown.
Three phenolic micropollutants, the antiseptic ortho-phenylphenol (OPP), the plastics additive bisphenol A (BPA) and the psychoactive drug dextrorphan were investigated with regard to the formation of potentially toxic, nitrophenolic TPs. Nitrite is an intermediate in the nitrification– denitrification process occurring in activated sludge and was found to cause nitration of these phenols. To elucidate the processes, incubation experiments were conducted in purified water in the presence of nitrite with OPP as the test substance. The reactive species HNO2, N2O3 and the radicals ·NO and ·NO2 were likely involved as indicated by scavenger experiments. In conditions found at WWTPs the wastewater is usually at neutral pH, and nitrite, being an intermediate, usually has a low concentration. By conducting incubation experiments inoculated with sludge from a conventional WWTP, it was found that the three phenolic micropollutants, OPP, BPA and dextrorphan were quickly transformed to biological TPs. Nitrophenolic TPs were only formed after artificial increase of the nitrite concentration or lowering of the pH. However, nitrophenolic-TPs can be formed as sample preparation artefacts through acidification or freezing for preservation, creating optimal conditions for the reaction to take place.
The final micropollutant to be studied was the pain-reliever diclofenac, a micropollutant on the EU-watch list due to ecotoxicological effects on rainbow trout. The transformation was compared in two different treatment systems, one employing a reactor with suspended carriers as a biofilm growth surface, while the other system employed conventional activated sludge. In the biofilm-based system, the pathway was found to produce many TPs each at relatively low concentration, many of which were intermediate TPs that were further degraded to unknown tertiary TPs. In the conventional activated sludge system some of the same reactions took place but all at much slower rates. The main difference between the two systems was due to different reaction rates rather than different transformation pathways. The municipal WWTPs were monitored to verify these results. In the biofilm system, a 10-day monitoring campaign confirmed an 88% removal of diclofenac and the formation of the same TPs as those observed in the laboratory experiments. The proposed environmental quality standard of 0.05 μg/L might thus be met without the need for additional treatment processes such as activated carbon filtration or ozonation.
Key mechanisms for the release of metal(loid)s from a construction material in hydraulic engineering
(2017)
Hydraulic engineering and thus construction materials are necessary to enable the navigability of water ways. Since, a variety of natural as well as artificial materials are used, this materials are world wide tested on a potential release of dangerous substances to prevent adverse effects on the environment. To determine the potential release, it is important to identify and to understand key mechanisms which are decisive for the release of hazardous substances. A limited correlation between the conditions used in regulatory tests and those found in environmental systems is given and hence, often the significance of results from standardised tests on construction materials is questioned, since they are not designed to mimic environmental conditions.
In Germany industrial by-products are used as armour stones in hydraulic engineering. Especially the by-product copper slag is used during the last 40 years for the construction of embankments, groynes and coastal protection. On the one hand, this material has a high density and natural resources (landscape) are protected. One the other hand, the material contains high quantities of metal(loid)s. Therefore the copper slag (product name: iron silicate stones) is very suitable as test material. Metal(loid)s examined were As, Sb and Mo as representatives for (hydr)oxide forming elements and Cd, Co, Cu, Fe, Ni, Pb and Zn were studied as representatives for elements forming cations during the release.
Questions addressed in this Thesis were: (i) can we transfer the results from batch experiments to construction scenarios under the prevalent environmental conditions, (ii) which long-term trends exist for the release of metal(loid)s from copper slags and (iii) how environmental conditions influence the leaching of metal(loid)s from water construction materials?
To answer the first question the surface depending release of the metal(loid)s from the construction materials was examined. Therefore, batch leaching experiments with different particle sizes and a constant liquid/solid ratio were performed. In a second step a comparison between different methods for the determination of the specific surface area of armour stones with a 3D laser scanning method as a reference were performed. In a last step it was possible to show that via a roughness factor the results of the specific surface area from small stones, measured with gas adsorption, can be connected with the results from armour stones, determined with an aluminium foil method. Based on calculations of the specific surface area, it was possible to significantly improve catchment scale calculation about the release of metal(loid)s and to evaluate a potential impact of construction materials in hydraulic engineering on the water chemistry of rivers and streams.
To answer the second question long-term leaching diffuse gradient in thin films supported experiments were performed for half a year. Diffuse gradients in thin films (DGT) is an in situ method to passive sample metal(loid)s in water, sediments and soils. They were used as a sink for metal(loid)s in the eluate to provide solution equilibriums. Thus the exchange of the eluent, which is performed normally in long-term experiments, was superfluous and long-term effects under undisturbed conditions were studied. The long-term leaching experiments with DGT have proven to be capable (i) to differentiate between the depletion of the material surface and the solution equilibriums and (ii) to study sorption processes with or without a further release of the analytes. This means for the practically relevant test material copper slag that: (i) the cations Cd, Co, Cu, Ni and Pb are confirmed to be released from the slag over the whole time period of six months, (ii) a surface depletion of Zn was detected, and (iii) that the (hydr)oxide forming elements As, Mo and Sb were released from the slag over the hole periods of six months but the release was masked by adsorption to Fe-oxide colloids, which were formed during the leaching experiments. It was confirmed, that sulphide minerals are the main source for long-term release of Cd, Cu, Ni, Pb and Mo.
To answer the third question short-term leaching experiments simulating environmental conditions in hydraulic engineering were performed. One factor is the salinity. The influence of this parameter was tested in batch experiments with sea salt solution (30 g/l), river Rhine water, ultra pure water and in addition with different NaCl concentration (5, 10, 20 and 30 g/l). In general, the ionic strength is an important factor for the metal(loid) release but the composition of the water (e.g. the HCO3- content) may superimpose this effect. Therefore, the concentrations of the metal(loid)s in the experiments with ultra-pure water spiked with sea salt or native river water and the ultra-pure water spiked with NaCl were significantly different. In a second experiment the influence of the environmental parameters and the interactions between the environmental parameters pH (4–10), sediment content (0 g–3.75 g), temperature (4 °C–36 °C) and ionic strength (0 g/l–30 g/l NaCl) on the release of metal(loid)s from the test material was examined. The statistical Design of Experiments (DoE) was used to study the influence of these factors as well as their interactions. All studied factors may impact the release of metal(loid)s from the test material to the eluent, whereas the release and the partitioning between sediment and eluate of metal(loid)s was impacted by interactions between the studied factors. The main processes were sorption, complexation, solubility, buffering and ion exchange. In addition, by separating the sediment from the slag after the experiments by magnetic separation, the enrichment of metal(loid)s in the sediment was visible. Thus, the sediment was the most important factor for the release of the metal(loid)s, via pH, temperature and ionic strength, because the sediment acted as a sink.
This bachelor thesis examines methods of Social Network Analysis in the context of in-house collaboration platforms and gives an overview of appropriate metrics based on findings in literature. Within this literature analysis advantages in analyzing these enterprise social networks for companies are pointed out. Also possible problems, for example relating to data protection, will be explained. Based on dynamical long-term analysis of the network of UniConnect it was detected, that measures of centrality show the connectedness of an actor. These measures allow drawing conclusions concerning position and function of the employee in the company. Furthermore the complexity of the network can be determined through clique analysis. By viewing at the gradual development of the network, it is possible to identify persons, who are strongly interconnected within a short period of time. These employees have strategic importance relating to knowledge management and the dissemination of information within the company.
This thesis presents two methods for the computation of global illumination. The first is an extension of Reflective Shadow Maps with an additional shadow test in order to handle occlusion. The second method is a novel, bidirectional Light-Injection approach. Rays originating from the light source are traced through the scene and stored inside the shafts of the Linespace datastructure. These shafts are a discretization of the possible spatial directions. The Linespaces are embedded in a Uniform Grid. When retrieving this pre-calculated lightning information no traversal of datastructures and no additional indirection is necessary in the best-case scenario. This reduces computation time and variance compared to Pathtracing. Areas that are mostly lit indirectly and glas profit the most from this. However, the result is only approximative in nature and produces visible artifacts.
With global and distributed project teams being increasingly common Collaborative Project Management is becoming the prevalent paradigm for the work in most organisations. Software has for many years been one of the most used tools for supporting Project Management and with the focus on Collaborative Project Management and accompanied by the emergence of Enterprise Collaboration Systems (ECS), Collaborative Project Management Software (CPMS) is gaining increased attention. This thesis examines the capabilities of CPMS for the long-term management of information which not only includes the management of files within these systems, but the management of all types of digital business documents, particularly social business documents. Previous research shows that social content in collaboration software is often poorly managed which poses challenges to meeting performance and conformance objectives in a business. Based on literature research, requirements for the long-term management of information in CPMS are defined and 7 CPMS tools are analysed regarding the content they contain and the functionalities for the long-term management of this content they offer. The study shows that CPMS by and large are not able to meet the long-term information management needs of an organisation on their own and that only the tools geared towards enterprise customers have sufficient capabilities to support the implementation of an Enterprise Information Management strategy.
The Web contains some extremely valuable information; however, often poor quality, inaccurate, irrelevant or fraudulent information can also be found. With the increasing amount of data available, it is becoming more and more difficult to distinguish truth from speculation on the Web. One of the most, if not the most, important criterion used to evaluate data credibility is the information source, i.e., the data origin. Trust in the information source is a valuable currency users have to evaluate such data. Data popularity, recency (or the time of validity), reliability, or vagueness ascribed to the data may also help users to judge the validity and appropriateness of information sources. We call this knowledge derived from the data the provenance of the data. Provenance is an important aspect of the Web. It is essential in identifying the suitability, veracity, and reliability of information, and in deciding whether information is to be trusted, reused, or even integrated with other information sources. Therefore, models and frameworks for representing, managing, and using provenance in the realm of Semantic Web technologies and applications are critically required. This thesis highlights the benefits of the use of provenance in different Web applications and scenarios. In particular, it presents management frameworks for querying and reasoning in the Semantic Web with provenance, and presents a collection of Semantic Web tools that explore provenance information when ranking and updating caches of Web data. To begin, this thesis discusses a highly exible and generic approach to the treatment of provenance when querying RDF datasets. The approach re-uses existing RDF modeling possibilities in order to represent provenance. It extends SPARQL query processing in such a way that given a SPARQL query for data, one may request provenance without modifying it. The use of provenance within SPARQL queries helps users to understand how RDF facts arederived, i.e., it describes the data and the operations used to produce the derived facts. Turning to more expressive Semantic Web data models, an optimized algorithm for reasoning and debugging OWL ontologies with provenance is presented. Typical reasoning tasks over an expressive Description Logic (e.g., using tableau methods to perform consistency checking, instance checking, satisfiability checking, and so on) are in the worst case doubly exponential, and in practice are often likewise very expensive. With the algorithm described in this thesis, however, one can efficiently reason in OWL ontologies with provenance, i.e., provenance is efficiently combined and propagated within the reasoning process. Users can use the derived provenance information to judge the reliability of inferences and to find errors in the ontology. Next, this thesis tackles the problem of providing to Web users the right content at the right time. The challenge is to efficiently rank a stream of messages based on user preferences. Provenance is used to represent preferences, i.e., the user defines his preferences over the messages' popularity, recency, etc. This information is then aggregated to obtain a joint ranking. The aggregation problem is related to the problem of preference aggregation in Social Choice Theory. The traditional problem formulation of preference aggregation assumes a I fixed set of preference orders and a fixed set of domain elements (e.g. messages). This work, however, investigates how an aggregated preference order has to be updated when the domain is dynamic, i.e., the aggregation approach ranks messages 'on the y' as the message passes through the system. Consequently, this thesis presents computational approaches for online preference aggregation that handle the dynamic setting more efficiently than standard ones. Lastly, this thesis addresses the scenario of caching data from the Linked Open Data (LOD) cloud. Data on the LOD cloud changes frequently and applications relying on that data - by pre-fetching data from the Web and storing local copies of it in a cache - need to continually update their caches. In order to make best use of the resources (e.g., network bandwidth for fetching data, and computation time) available, it is vital to choose a good strategy to know when to fetch data from which data source. A strategy to cope with data changes is to check for provenance. Provenance information delivered by LOD sources can denote when the resource on the Web has been changed last. Linked Data applications can benefit from this piece of information since simply checking on it may help users decide which sources need to be updated. For this purpose, this work describes an investigation of the availability and reliability of provenance information in the Linked Data sources. Another strategy for capturing data changes is to exploit provenance in a time-dependent function. Such a function should measure the frequency of the changes of LOD sources. This work describes, therefore, an approach to the analysis of data dynamics, i.e., the analysis of the change behavior of Linked Data sources over time, followed by the investigation of different scheduling update strategies to keep local LOD caches up-to-date. This thesis aims to prove the importance and benefits of the use of provenance in different Web applications and scenarios. The exibility of the approaches presented, combined with their high scalability, make this thesis a possible building block for the Semantic Web proof layer cake - the layer of provenance knowledge.
Mapping ORM to TGraph
(2017)
Object Role Modeling (ORM) is a semantic modeling language used to describe objects and their relations amongst each other. Both objects and relations may be subject to rules or ORM constraints.
TGraphs are ordered, attributed, typed and directed graphs. The type of a TGraph and its components, the edges and vertices, is defined using the schema language graph UML (grUML), a profiled version of UML class diagrams. The goal of this thesis is to map ORM schemas to grUML schemas in order to be able to represent ORM schema instances as TGraphs.
Up to this point, the preferred representation for ORM schema instances is in form of relational tables. Though mappings from ORM schemas to relational schemas exist, those publicly available do not support most of the constraints ORM has to offer.
Constraints can be added to grUML schemas using the TGraph query language GReQL, which can efficiently check whether a TGraph validates the constraint or not. The graph library JGraLab provides efficient implementations of TGraphs and their query language GReQL and supports the generation of grUML schemas.
The first goal of this work is to perform a complete mapping from ORM schemas to grUML schemas, using GReQL to sepcify constraints. The second goal is to represent ORM instances in form of TGraphs.
This work gives an overview of ORM, TGraphs, grUML and GReQL and the theoretical mapping from ORM schemas to grUML schemas. It also describes the implementation of this mapping, deals with the representation of ORM schema instances as TGraphs and the question how grUML constraints can be validated.
Wahlordnung der örtlichen Studierendenschaft
der Universität Koblenz-Landau, Campus Landau
Ordnung zur Änderung der Einschreibeordnung für
die Universität Koblenz-Landau
Promotionsordnung des Fachbereichs 5: Erziehungswissenschaften
der Universität Koblenz-Landau
Erste Ordnung zur Änderung der Promotionsordnung
des Fachbereiches 6: Kultur- und Sozialwissenschaften
der Universität Koblenz–Landau
Änderungssatzung zur Satzung über die Festsetzung
von Zulassungszahlen an der Universität Koblenz-
Landau für das Studienjahr 2016/2017
Erste Ordnung zur Änderung der Ordnung für die
Eignungsprüfung Musik an der Universität Koblenz-
Landau
Siebzehnte Ordnung zur Änderung der Prüfungsordnung
für die Prüfung im lehramtsbezogenen Bachelorstudiengang
an der Universität Koblenz-
Landau
Redaktionelle Korrektur betreffend die Ordnung zur
Änderung der Einschreibeordnung für die Universität
Koblenz-Landau
Ordnung zur Änderung der Beitragsordnung des
Studierendenwerks Koblenz
Ordnung zur Aufhebung der Prüfungsordnung für
den Bachelorstudiengang Anglistik und Medienmanagement
/ English Studies and Media Management
an der Universität Koblenz-Landau
Achtzehnte Ordnung zur Änderung der Prüfungsordnung
für die Prüfung im lehramtsbezogenen Bachelorstudiengang an der Universität Koblenz-Landau
Sechzehnte 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
Fünfzehnte Ordnung zur Änderung der Ordnung für
die Prüfung im lehramtsbezogenen Zertifikatsstudiengang
(Erweiterungsprüfung) an der Universität
Koblenz-Landau
Dreizehnte Ordnung zur Änderung der Prüfungsordnung
für die Prüfung im Zwei-Fach-Bachelorstudiengang
an der Universität Koblenz-Landau
Zweite Ordnung zur Änderung der Gemeinsamen
Prüfungsordnung für die Bachelor- und Masterstudiengänge
des Fachbereichs Informatik an der Universität
Koblenz-Landau
Fünfte Ordnung zur Änderung der Ordnung für die
Prüfung im Bachelorstudiengang Umweltwissenschaften
und in den Masterstudiengängen Umweltwissenschaften
/ Environmental Sciences und
Ecotoxicology an der Universität Koblenz-Landau,
Campus Landau
Erste Ordnung zur Änderung der Gemeinsamen
Prüfungsordnung für den Bachelorstudiengang
„Mathematische Modellierung“ und den Masterstudiengang
„Mathematical Modeling of Complex Systems“
an der Universität Koblenz-Landau
Erste Ordnung zur Änderung der Gemeinsamen
Prüfungsordnung für den Bachelorstudiengang
„Angewandte Naturwissenschaften“ und den Masterstudiengang
„Chemie und Physik funktionaler
Materialien“ an der Universität Koblenz-Landau
Zweite Ordnung zur Änderung der Prüfungsordnung
für Studierende des Bachelorstudiengangs
„Pädagogik“ (B.A.) und des Masterstudiengangs
„Erziehungswissenschaft mit dem Schwerpunkt
Forschung und Entwicklung in Organisationen“
(M.A.) des Fachbereichs 1: Bildungswissenschaften
an der Universität Koblenz-Landau, Campus Koblenz
Erste Ordnung zur Änderung der Promotionsordnung des Fachbereiches 3: Mathematik / Naturwissenschaften der Universität Koblenz–Landau
Prüfungsordnung für den Bachelorstudiengang „Mensch und Umwelt: Psychologie, Kommunikation, Ökonomie“ an der Universität Koblenz-Landau, Campus Landau
Sechzehnte Ordnung zur Änderung der Prüfungsordnung für die Prüfung im lehramtsbezogenen Bachelorstudiengang an der Universität Koblenz-Landau
Fünfzehnte 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
Vierzehnte Ordnung zur Änderung der Ordnung für die Prüfung im lehramtsbezogenen Zertifikatsstudiengang (Erweiterungsprüfung) an der Universität Koblenz-Landau
Achte Ordnung zur Änderung der Prüfungsordnung für die Prüfung im lehramtsbezogenen Bachelorstudiengang Berufsbildende Schulen an der Universität Koblenz-Landau, der Hochschule Koblenz und der Philosophisch-Theologischen Hochschule Vallendar
Siebte Ordnung zur Änderung der Ordnung für die
Prüfung im Masterstudiengang Lehramt an berufsbildenden Schulen an der Universität Koblenz-Landau, der Hochschule Koblenz und der Philosophisch-Theologischen Hochschule Vallendar
Beitragsordnung der Studierendenschaft der Universität Koblenz-Landau, Campus Landau
Satzung zur Festsetzung der Normwerte für den Ausbildungsaufwand (Curricularnormwerte) der Universität Koblenz-Landau
Satzung zur Festsetzung von Zulassungszahlen an der Universität Koblenz-Landau für das Studienjahr 2017/2018
Neunzehnte Ordnung zur Änderung der Prüfungsordnung für die Prüfung im lehramtsbezogenen Bachelorstudiengang an der Universität Koblenz Landau
Siebzehnte 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
Sechzehnte Ordnung zur Änderung der Ordnung für die Prüfung im lehramtsbezogenen Zertifikatsstudiengang (Erweiterungsprüfung) an der Universität Koblenz Landau
Vierzehnte Ordnung zur Änderung der Prüfungsordnung für die Prüfung im Zwei-Fach-Bachelorstudiengang an der Universität Koblenz-Landau
Ordnung zur Änderung der Einschreibeordnung für die Universität Koblenz-Landau
Redaktionelle Korrektur betreffend die Vierzehnte Ordnung zur Änderung der Prüfungsordnung für die Prüfung im Zwei-Fach-Bachelorstudiengang an der Universität Koblenz-Landau
Satzung der örtlichen Studierendenschaft an der Universität Koblenz-Landau, Campus Koblenz
Sechste Ordnung zur Änderung der Ordnung für die Prüfung im Bachelorstudiengang Umweltwissenschaften und in den Masterstudiengängen Umweltwissenschaften / Environmental Sciences und Ecotoxicology an der Universität Koblenz-Landau, Campus Landau
Zwanzigste Ordnung zur Änderung der Prüfungsordnung
für die Prüfung im lehramtsbezogenen Bachelorstudiengang
an der Universität Koblenz-Landau
Zweite Ordnung zur Änderung der Ordnung für die Prüfung im Bachelorstudiengang und im Masterstudiengang BioGeoWissenschaften der Universität Koblenz-Landau
Fünfzehnte Ordnung zur Änderung der Prüfungsordnung für die Prüfung im Zwei-Fach-Bachelorstudiengang an der Universität Koblenz-Landau
Sechste Ordnung zur Änderung der Prüfungsordnung für den Bachelorstudiengang und den Masterstudiengang „Sozial- und Kommunikationswissenschaften“ des Fachbereichs 6: Kultur- und Sozialwissenschaften an der Universität Koblenz-Landau
Die Forschung im Bereich der modellbasierten Objekterkennung und Objektlokalisierung hat eine vielversprechende Zukunft, insbesondere die Gebäudeerkennung bietet vielfaltige Anwendungsmöglichkeiten. Die Bestimmung der Position und der Orientierung des Beobachters relativ zu einem Gebäude ist ein zentraler Bestandteil der Gebäudeerkennung.
Kern dieser Arbeit ist es, ein System zur modellbasierten Poseschätzung zu entwickeln, das unabhängig von der Anwendungsdomäne agiert. Als Anwendungsdomäne wird die modellbasierte Poseschätzung bei Gebäudeaufnahmen gewählt. Vorbereitend für die Poseschätzung bei Gebäudeaufnahmen wird die modellbasierte Erkennung von Dominosteinen und Pokerkarten realisiert. Eine anwendungsunabhängige Kontrollstrategie interpretiert anwendungsspezifische Modelle, um diese im Bild sowohl zu lokalisieren als auch die Pose mit Hilfe dieser Modelle zu bestimmen. Es wird explizit repräsentiertes Modellwissen verwendet, sodass Modellbestandteilen Bildmerkmale zugeordnet werden können. Diese Korrespondenzen ermöglichen die Kamerapose aus einer monokularen Aufnahme zurückzugewinnen. Das Verfahren ist unabhängig vom Anwendungsfall und kann auch mit Modellen anderer rigider Objekte umgehen, falls diese der definierten Modellrepräsentation entsprechen. Die Bestimmung der Pose eines Modells aus einem einzigen Bild, das Störungen und Verdeckungen aufweisen kann, erfordert einen systematischen Vergleich des Modells mit Bilddaten. Quantitative und qualitative Evaluationen belegen die Genauigkeit der bestimmten Gebäudeposen.
In dieser Arbeit wird zudem ein halbautomatisches Verfahren zur Generierung eines Gebäudemodells vorgestellt. Das verwendete Gebäudemodell, das sowohl semantisches als auch geometrisches Wissen beinhaltet, den Aufgaben der Objekterkennung und Poseschätzung genügt und sich dennoch an den bestehenden Normen orientiert, ist Voraussetzung für das Poseschätzverfahren. Leitgedanke der Repräsentationsform des Modells ist, dass sie für Menschen interpretierbar bleibt. Es wurde ein halbautomatischer Ansatz gewählt, da die automatische Umsetzung dieses Verfahrens schwer die nötige Präzision erzielen kann. Das entwickelte Verfahren erreicht zum einen die nötige Präzision zur Poseschätzung und reduziert zum anderen die Nutzerinteraktionen auf ein Minimum. Eine qualitative Evaluation belegt die erzielte Präzision bei der Generierung des Gebäudemodells.
Hintergrund: Veränderte gesetzliche Rahmenbedingungen in der stationären Altenhilfe, die demografische Entwicklung mit dem steigenden Bedarf an Pflegekräften einerseits und die Tatsache, dass immer weniger Menschen aufgrund des Images des Berufes und der Arbeitsbedingungen in der Pflege tätig sein wollen andererseits, machen es notwendig neue Wege zu suchen. Die Träger im Sozial- und Gesundheitswesen sind gefordert, Konzepte zu entwickeln, die ihre Wirtschaftlichkeit sichern, gleichzeitig aber auch den Belastungen und der Unzufriedenheit von Mitarbeitenden entgegenwirken. Es braucht Gestaltungsräume, um Lösungen im Konflikt zwischen Anspruch und Machbarkeit zu finden und so dem alltäglichen Stress, der Mitarbeiterfluktuation und dem drohenden Leistungsabfall entgegenzuwirken. Durch das Praxisprojekt eines sozial-karitativen Trägers zur Implementierung einer ´Konstruktiven Konfliktkultur´ in einer stationären Altenhilfeeinrichtung sollte eine Organisationskultur geschaffen werden, in der Konflikte offen angesprochen werden, eine Offenheit für Veränderungsprozesse entsteht, Belastungen reduziert und die Mitarbeitenden an die Organisation gebunden werden. Dazu wurden drei pädagogische Interventionen entwickelt, durch die die Mitarbeitenden und die Führungskräfte in ihrer Konfliktfähigkeit geschult werden sollten. Methode: Die wissenschaftliche Begleitung dieses Praxisprojektes fand als Evaluationsstudie statt. Zu drei Erhebungszeitpunkten wurde eine repräsentative Mitarbeitergruppe dieser Einrichtung zu den Themen Konflikterleben, Führungsverhalten, Macht/ Regeln und Veränderungen durch qualitative Leitfadeninterviews befragt. Die Auswertung und Analyse der Daten erfolgte im Sinne der qualitativen Inhaltsanalyse nach Mayring und floss ein in eine formative Prozessevaluation der einzelnen Interventionen und einer summativen Effektevaluation zu Bewertung der Zielerreichung des Projektes. Ergebnis: Die einzelnen Interventionen des Projektes konnten nicht dazu beitragen, dass eine ´Konstruktiven Konfliktkultur´ nachhaltig entwickelt werden konnte. Zwar gab es in der Bewusstseinsspanne des Projektes einen expliziten Wissensgewinn, jedoch mehr bei den Führungskräften als bei den Mitarbeitenden. Die Führungskräfte sahen im Projekt einen Gewinn, für einen Teil der Mitarbeitenden war es sogar Zeitverschwendung. Anhand der Ergebnisse lassen sich drei Merkmale herauskristallisieren, die kennzeichnend sind für die zugrundeliegenden Denk-, Urteils-, und Handlungsstrukturen in sozialen Organisationen im Umgang mit Konflikten: Konflikte sind nicht wahrnehmbare Konstrukte der Alltagswelt. Sie manifestieren sich aufgrund fehlender Legitimation in Überforderung und eine ´Konstruktiven Konfliktkultur´ kann nicht auf das Wissen Einzelner aufbauen, sondern benötigt verbindliche Handlungsstrukturen für alle Organisationsmitglieder gleichermaßen. Ergebnisinterpretation: Durch die Einbeziehung wissenssoziologischer und konfliktsoziologischer Theorien und deren Einordnung in Institutionen – und Organisationstheorien konnten die Ergebnisse diskutiert und neue Erkenntnisse über Konflikte in Organisationen, die sich in drei Spannungsfeldern zeigen, gewonnen werden. Die Spannungsfelder bewegen sich zwischen dem Konflikt als nicht-wahrnehmbarem Alltagsphänomen auf der einen Seite und einer manifestierten Belastung auf der anderen Seite, dem Gewohnheitswissen im alltäglichen Umgang einerseits und einem fehlenden Handlungswissen andererseits, einer funktional-positiven Sicht hier und einer dysfunktional-negativen Sicht dort. Anhand dieser Spannungsfelder kann die Konfliktmentalität und ihre Entstehung und auch die Möglichkeit ihrer Veränderbarkeit reflektiert und können Erfolgsfaktoren für die Implementierung einer ´Konstruktiven Konfliktkultur´ entwickelt werden.
Schlussfolgerung: Wissen, Legitimation und Institutionalisierung und die Stärkung der Wahrnehmungen sind der Schlüssel für die Veränderung der Konfliktmentalität in sozialen Organisationen. Nachhaltigkeit erhält die Thematik aber erst, wenn alle Organisationsmitglieder eine gewisse Handlungsnotwendigkeit für sich erkennen. Aktuell steht die Organisationsentwicklung für den expliziten Veränderungswillen von Management, der jedoch auf ein gewisses Beharrungsvermögen von Mitarbeitenden trifft.
This thesis proposes the use of MSR (Mining Software Repositories) techniques to identify software developers with exclusive expertise about specific APIs and programming domains in software repositories. A pilot Tool for finding such
“Islands of Knowledge” in Node.js projects is presented and applied in a case study to the 180 most popular npm packages. It is found that on average each package has 2.3 Islands of Knowledge, which is possibly explained by the finding that npm packages tend to have only one main contributor. In a survey, the maintainers of 50 packages are contacted and asked for opinions on the results produced by the Tool. Together with their responses, this thesis reports on experiences made with the pilot Tool and how future iterations could produce even more accurate statements about programming expertise distribution in developer teams.
The implementation of physiological indicators reflecting the response of organisms to changes in their environment is assumed to provide potential benefits for ecological studies. By analysing the physiological condition of organisms in freshwater ecological studies rather than their ultimate effects, physiological indicators can contribute to a faster assessment of effects than using traditional ecological indicators, such as the evaluation of the benthic community structure or the determination of the reproductive success of organisms. This can increase the effectiveness of environmental health assessment and experimental ecology. In this respect the thesis focuses on physiological measures characterizing the energetic condition and energy consumption (the concentration of energy storage compounds, the adenylate energy charge, the energy consumption in vivo), as well as individual growth (RNA:DNA ratio) of organisms. Although these sub-individual indicators are commonly applied in marine ecology and more recently in ecotoxicology, they have been rarely applied in freshwater ecology to date. With respect to an increased use of physiological indicators in freshwater ecological studies, the objectives of the present thesis are twofold. First, it highlights the potential of assessing the individual fitness by means of physiological indicators in freshwater ecological studies. For that reason, Chapter 2 provides the basic assumptions as well as the theoretical and methodological fundamentals necessary for the application of physiological indicators within freshwater ecology and, furthermore, points out their applicability by several case studies. As second objective, the thesis addresses selected ecophysiological aspects of native and non-native freshwater amphipods, which are considered suitable candidates for the determination of physiological indicators in ecological studies due to their function as keystone species within aquatic habitats. The studies presented in Chapters 3−5 of the thesis provide information on (i) species- and sex-specific seasonal variations within the energetic condition of natural Gammarus populations (G. fossarum, G. pulex), (ii) differences in metabolic activity and behaviour between different amphipod species (G fossarum, G. roeselii and D. villosus), as well as (iii) the direct effects of ambient ammonia on the physiology and behaviour of D. villosus. The fundamental conclusions drawn from the conducted field and laboratory studies, as well as their relevance and general implications for the application of physiological indicators in freshwater ecological research are discussed in Chapter 6.
Natural pest control and pollination are important ecosystem services for agriculture. They can be supported by organic farming and by seminatural habitats at the local and landscape scale.
The potential of seminatural habitats to support predatory flies (chapters 2 and 3) and bees(chapter 7) at the local and landscape scale was investigated in seminatural habitats. Predatory flies were more abundant in woody habitats and positively related to landscape complexity. The diversity and the abundance of honey and wild bees were positively related to the supply of flowers offered in the seminatural habitats.
The influence of organic farming, adjacent seminatural habitats and landscape complexity on pest control (chapter 4) and pollination (chapter 6) was investigated in 18 pumpkin fields. Organic farming lacked strong effects both on the pest control and on the pollination of pumpkin.
Pest control is best supported at the local scale by the flower abundance in the adjacent habitat. The flower supply positively affected the density of natural enemies and tended to reduce aphid densities in pumpkin fields.
Pumpkin provides a striking example for a dominant role of wild pollinators for pollination success, because bumble bees are the key pollinators of pumpkin in Germany, despite a higher visitation frequency of honey bees. Pollination is best supported by landscape complexity. Bumble bee visits and as a result pollen delivery in pumpkin were negatively related to the dominance of agricultural land in the surrounding landscape.
The influence of aphid density (chapter 8) and pollination (chapter 5) on pumpkin yield was evaluated. Pumpkin yields were not affected by aphid densities observed in the pumpkin fields and not limited by pollination at the current levels of bee visitation.
In conclusion, especially seminatural habitats, that provide diverse, continuous floral resources, are important for natural enemies and pollinators. A sufficient proportion of different seminatural habitat types in agricultural landscapes should be maintained and restored. Thereby natural enemies such as predatory flies, wild pollinators such as bumble bees, and the pest control and pollination provided by them can be supported.
This thesis explores the possibilities of probabilistic process modelling for the Computer Supported Cooperative Work (CSCW) systems in order to predict the behaviour of the users present in the CSCW system. Toward this objective applicability, advantages, limitations and challenges of probabilistic modelling are excavated in context of CSCW systems. Finally, as a primary goal seven models are created and examined to show the feasibilities of probabilistic process discovery and predictions of the users behaviour in CSCW systems.
Motion capture refers to the process of capturing, processing and trans- lating real motions onto a 3D model. Not only in the movie and gaming industries, motion capture creates an indispensable realism of human and animal movement. Also in the context of robotics, medical movement therapy, as well as in AR and VR, motion capture is used extensively. In addition to the well established optical processes, especially in the last three areas, alternative systems based on inertial navigation (IMUs) are being used in-creasingly, because they do not rely on external cameras and thus limit the area of movement considerably less.
Fast evolving technical progress in the manufacturing of such IMUs allows building small sensors, wearable on the body which can transfer movements to a computer. The development of applying inertial systems to a motion capture context, however, is still at an early state. Problems like drift can currently only be minimized by adding additional hardware for correcting the read data.
In the following master thesis an IMU based motion capture system is designed and constructed. This contains the assembly of the hardware components as well as processing of the received movement data on the software side and their application to a 3D model.
Introduction:
In March 2012 a secessionist-Islamist insurgency gained momentum in Mali and quickly took control of two-thirds of the state territory. Within weeks radical Islamists, drug smugglers and rebels suddenly ruled over a territory bigger than Germany. News of the abuse of the population and the introduction of harsh Sharia law spread soon, and word got out that the Malian Army had simply abandoned the land. The general echo of the IC was surprise, a reaction that was, as this research will show, as unfunded as it was unconstructive*. When Malian state structures collapsed, the world watched in shock, even though the developments couldhave been anticipated –and prevented. Ultimately, the situation had to be resolved by international forces (most notably French troops), who are still in Mali at the time of writing (Arieff 2013a: 5; Lohmann 2012: 3; Walther and Christopoulos 2015: 514f.; Shaw 2013: 204; Qantara, Interview, 2012;L’Express, Mali, 2015; Deutscher Bundestag, MINUSMA und EUTM Mali, 2016; UN, MUNISMA, 2016; Boeke and Schuurmann 2015: 801; Chivvis 2016: 93f.).
This research will show that the developments in Mali in 2012 have been developing for a long time and could have been avoided. In doing so, it will also show why state security can never be analyzed or consolidated in an isolated manner. Instead, it is necessary to take into account regional dynamics and developments in order to find a comprehensive approach to security in individual states. Once state failure occurs, not only does the state itself fail, but the surrounding region equally failed to prevent the failure.
Weak states are a growing concern in many world regions, particularly in Africa. As international intervention often proves unsustainable for various reasons*, the author believes that states which cannot stabilize themselves need a regional agent to support them. This regional agent should be a Regional Security Complex (RSC) asdefined by Barry Buzan and Ole Waever (Buzan and Waever 2003). As the following analysis will show, Mali is a case in point. The hope is that this study will help avoid similar failures in the future by making a strong case for the establishment of RSC’s.
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Using semantic data from general-purpose programming languages does not provide the unified experience one would want for such an application. Static error checking is lacking, especially with regards to static typing of the data. Based on the previous work of λ-DL, which integrates semantic queries and concepts as types into a typed λ-calculus, this work takes its ideas a step further to meld them into a real-world programming language. This thesis explores how λ-DL's features can be extended and integrated into an existing language, researches an appropriate extension mechanism and produces Semantics4J, a JastAdd-based Java language semantic data extension for type-safe OWL programming, together with examples of its usage.
In scientific data visualization huge amounts of data are generated, which implies the task of analyzing these in an efficient way. This includes the reliable detection of important parts and a low expenditure of time and effort. This is especially important for the big-sized seismic volume datasets, that are required for the exploration of oil and gas deposits. Since the generated data is complex and a manual analysis is very time-intensive, a semi-automatic approach could on one hand reduce the time required for the analysis and on the other hand offer more flexibility, than a fully automatic approach.
This master's thesis introduces an algorithm, which is capable of locating regions of interest in seismic volume data automatically by detecting anomalies in local histograms. Furthermore the results are visualized and a variety of tools for the exploration and interpretation of the detected regions are developed. The approach is evaluated by experiments with synthetic data and in interviews with domain experts on the basis of real-world data. Conclusively further improvements to integrate the algorithm into the seismic interpretation workflow are suggested.
Part-of-Speech tagging is the process of assigning words with similar grammatical properties to a part of speech (PoS). In the English language, PoS-tagging algorithms generally reach very high accuracy. This thesis undertakes the task to test against these accuracies in PoS-tagging as a qualitative measure in classification capabilities for a recently developed neural network model, called graph convolutional network (GCN). The novelty proposed in this thesis is to translate a corpus into a graph as a direct input for the GCN. The experiments in this thesis serve as a proof of concept with room for improvements.
Statistical eco(-toxico)logy
(2017)
Freshwaters are of immense importance for human well-being.
Nevertheless, they are currently facing unprecedented levels of threat from habitat loss and degradation, overexploitation, invasive species and
pollution.
To prevent risks to aquatic ecosystems, chemical substances, like agricultural pesticides, have to pass environmental risk assessment (ERA) before entering the market.
Concurrently, large-scale environmental monitoring is used for surveillance of biological and chemical conditions in freshwaters.
This thesis examines statistical methods currently used in ERA.
Moreover, it presents a national-scale compilation of chemical monitoring data, an analysis of drivers and dynamics of chemical pollution in streams and, provides a large-scale risk assessment by combination with results from ERA.
Additionally, software tools have been developed to integrate different datasets used in ERA.
The thesis starts with a brief introduction to ERA and environmental monitoring and gives an overview of the objectives of the thesis.
Chapter 2 addresses experimental setups and their statistical analyses using simulations.
The results show that current designs exhibit unacceptably low statistical power, that statistical methods chosen to fit the type of data provide higher power and that statistical practices in ERA need to be revised.
In chapter 3 we compiled all available pesticide monitoring data from Germany.
Hereby, we focused on small streams, similar to those considered in ERA and used threshold concentrations derived during ERA for a large-scale assessment of threats to freshwaters from pesticides.
This compilation resulted in the most comprehensive dataset on pesticide exposure currently available for Germany.
Using state-of-the-art statistical techniques, that explicitly take the limits of quantification into account, we demonstrate that 25% of small streams are at threat from pesticides.
In particular neonicotinoid pesticides are responsible for these threats.
These are associated with agricultural intensity and can be detected even at low levels of agricultural use.
Moreover, our results indicated that current monitoring underestimates pesticide risks, because of a sampling decoupled from precipitation events.
Additionally, we provide a first large-scale study of annual pesticide exposure dynamics.
Chapters 4 and 5 describe software solutions to simplify and accelerate the integration of data from ERA, environmental monitoring and ecotoxicology that is indispensable for the development of landscape-level risk assessment.
Overall, this thesis contributes to the emerging discipline of statistical ecotoxicology and shows that pesticides pose a large-scale threat to small streams.
Environmental monitoring can provide a post-authorisation feedback to ERA.
However, to protect freshwater ecosystems ERA and environmental monitoring need to be further refined and we provide software solutions to utilise existing data for this purpose.
One of the greatest goals in computer graphics is the aesthetic representation of objects. In addition to conventional methods, another field focuses on non-photorealistic renderings. The so-called example-based rendering is an area where users can transfer their art style to a pre-computed 3D rendering, using a hand-painted template. There are some algorithms that already provide impressive results, but their problem is that most of these procedures count as offline methods and are not able to produce results in real-time. For this reason, this work show a method that satisfies this condition. In addition, the influence of the run-time reduction on the results is investigated. Requirements are defined, to which the method and its results are examined. Other methods in this field are referenced and compared with their results.
While real-time applications used to be executed on highly specialized hardware and individually developed operation systems, nowadays more often regular off-the-shelf hardware is used, with a variation of the Linux kernel running on top.
Within the scope of this thesis, test methods have been developed and implemented as a real-time application to measure several performance properties of the Linux kernel with regards to its real-time capability.
These tests have been run against three different versions of the Linux kernel. Afterwards, the results of the test series were compared to each other.
Pelagic oxyclines, the transition zone between oxygen rich surface waters and oxygen depleted deep waters, are a common characteristic of eutrophic lakes during summer stratification. They can have tremendous effects on the biodiversity and the ecosystem functioning of lakes and, to add insult to injury, are expected to become more frequent and more pronounced as climate warming progresses. On these grounds, this thesis endeavors to advance the understanding of formation, persistence, and consequences of pelagic oxyclines: We test, whether the formation of metalimnetic oxygen minima is intrinsically tied to a locally enhanced oxygen consuming process, investigate the relative importance of vertical physical oxygen transport and biochemical oxygen consumption for the persistence of pelagic oxyclines, and finally assess their potential consequences for whole lake cycling. To pursue these objectives, the present thesis nearly exclusively resorts to in situ measurements. Field campaigns were conducted at three lakes in Germany featuring different types of oxyclines and resolved either a short (hours to days) or a long (weeks to months) time scale. Measurements comprised temperature, current velocity, and concentrations of oxygen and reduced substances in high temporal and vertical resolution. Additionally, vertical transport was estimated by applying the eddy correlation technique within the pelagic region for the first time. The thesis revealed, that the formation of metalimnetic oxygen minima does not necessarily depend on locally enhanced oxygen depletion, but can solely result from gradients and curvatures of oxygen concentration and depletion and their relative position to each other. Physical oxygen transport was found to be relevant for oxycline persistence when it considerably postponed anoxia on a long time scale. However, its influence on oxygen dynamics was minor on short time scales, although mixing and transport were highly variable. Biochemical consumption always dominated the fate of oxygen in pelagic oxyclines. It was primarily determined by the oxidative breakdown of organic matter originating from the epilimnion, whereas in meromictic lakes, the oxidation of reduced substances dominated. Beyond that, the results of the thesis emphasize that pelagic oxyclines can be a hotspot of mineralization and, hence, short-circuit carbon and nutrient cycling in the upper part of the water column. Overall, the present thesis highlights the importance of considering physical transport as well as biochemical cycling in future studies.
Grassland management has been increasingly intensified throughout centuries since mankind started to control and modify the landscape. Species communities were always shaped alongside management changes leading to huge alterations in species richness and diversity up to the point where land use intensity exceeded the threshold. Since then biodiversity became increasingly lost. Today, global biodiversity and especially grassland biodiversity is pushed beyond its boundaries. Policymakers and conservationists seek for management options which fulfill the requirements of agronomic interests as well as biodiversity conservation alongside with the maintenance of ecosystem processes. However, there is and will always be a trade-off.
Earlier in history, natural circumstances in a landscape mainly determined regionally adapted land use. These regional adaptions shaped islands for many specialist species, and thus diverse species communities, favoring the establishment of a high β-diversity. With the raising food demand, these regional and traditional management regimes became widely unprofitable, and the invention of mineral fertilizers ultimately led to a wide homogenization of grassland management and, as follows, the loss of biotic heterogeneity. In the course of the green revolution, this immediate coherence and the dependency between grassland biodiversity and traditional land use practices becomes increasingly noticed. Indeed, some traditional forms of management such as meadow irrigation have been preserved in a few regions and thus give us the opportunity to directly investigate their long-term relevance for the species communities and ecosystem processes. Traditional meadow irrigation was a common management practice to improve productivity in lowland, but also alpine hay meadows throughout Europe until the 20th century. Nowadays, meadow irrigation is only practiced as a relic in a few remnant areas. In parts of the Queichwiesen meadows flood irrigation goes back to the Middle Ages, which makes them a predestined as a model region to study the long- and short-term effects of lowland meadow irrigation on the biodiversity and ecosystem processes.
Our study pointed out the conservation value of traditional meadow irrigation for the preservation of local species communities as well as the plant diversity at the landscape scale. The structurally more complex irrigated meadows lead to the assumption of a higher arthropod diversity (Orthodoptera, Carabidae, Araneae), which could not be detected. However, irrigated meadows are a significant habitat for moisture dependent arthropod species. In the light of the agronomic potential, flood irrigation could be a way to at least reduce fertilizer costs to a certain degree and possibly prevent overfertilization pulses which are necessarily hazardous to non-target ecosystems. Still, the reestablishment of flood irrigation in formerly irrigated meadows, or even the establishment of new irrigation systems needs ecological and economic evaluation dependent on regional circumstances and specific species communities, at which this study could serve as a reference point.
In der vorliegenden Arbeit wird das thermochemische Wechselwirkungsverhalten verschiedener Magnesiakohlenstoffmaterialen in Abhängigkeit verschiedener Einflussgrößen wissenschaftlich untersucht. Schwerpunkte der experimentellen Arbeiten bilden thermoanalytische Experimente, Gefügeuntersuchungen der Magnesiakohlenstoff-Proben sowie thermodyna-mische Berechnungen und Auswertungen durch CAT (Computer Aided Thermochemistry) mittels des Softwarepakets FactSage.
Erster Themenbereich dieser Arbeit ist die Untersuchung des Einflusses der in dem Rohstoff Magnesia enthaltenen mineralogischen Nebenphasen Merwinit (C3MS2), Monticellit (CMS) und Belit (C2S) auf den carbothermisch induzierten Verschleiß im MgO-C-Material. Für die Messreihen wurden die Nebenphasen eigens synthetisiert und hiermit MgO-C-Nebenphase-Modellwerkstoffe hergestellt. Die Nebenphase Monticellit ist unbeständig gegenüber der carbothermischen Reduktion. Monticellit wird im MgO-C-Gefüge durch Kohlenstoff reduziert und hieraus ergibt sich ein erhöhter Gewichtsverlust des Probenmaterials. Auch Merwinit wird bei T = 1600°C reduziert, der Gewichtsverlust wird dadurch allerdings nicht erhöht. Belit ist im MgO-C-Gefüge stabil gegenüber carbothermischer Reduktion.
Ein weiterer Schwerpunkt der Arbeit lag auf der Untersuchung des Einflusses des klassischen Antioxidans Aluminium auf die thermochemische Stabilität von MgO-C. Bei geringen Sauerstoffpartialdrücken ist die Reaktion des Aluminium-Metalls bzw. des bereits zu Al4C3 carbidisierten Aluminiums mit dem steineigenen Periklas unter Mg(g)-Bildung möglich, was einen erhöhten Gewichtsverlust zur Folge hat. Aber auch nach der Oxidation zu Al2O3 bzw. Spinell liegt Aluminium in signifikanten Mengen als Al(g) und Al2O(g) in der Gasphase vor und greift des Weiteren die Nebenphasen an, was ebenfalls zu einem messbaren Gewichtsverlust führt.
Dritter Arbeitsschwerpunkt war die Untersuchung des Einflusses des Umgebungsdruckes auf die carbothermische Reduktion von MgO. Die Ergebnisse zeigen, dass der Druck sich in zweierlei Hinsicht auf die carbothermische Reduktion von MgO auswirkt. Zum einen bewirkt ein sinkender Umgebungsdruck eine Beschleunigung der carbothermischen Reduktion durch die Verschiebung des thermodynamischen Gleichgewichts auf die Produktseite. Des Weiteren sorgt er für einen schnelleren Abtransport der Produktgase vom Reaktionsort und ver-hindert somit die Einstellung eines lokalen Gleichgewichts im Gefüge. Dritter Effekt ist die mit steigendem Druck verstärkt ablaufende Kohlenstoffoxidation durch Umgebungssauerstoff, da die Sauerstoffmenge in der Umgebung des MgO-C-Materials vom Umgebungsdruck bestimmt wird. Für die Geschwindigkeit des thermochemischen Verschleißes von Magnesiakohlenstoffmaterialien, der immer eine Kombination aus Kohlenstoffoxidation und carbothermischer Reduktion darstellt, bedeutet dies, dass sie in Abhängigkeit vom Umgebungsdruck in unterschiedlichem Ausmaß von diesen beiden Reaktionen beeinflusst wird.
Im Bereich Augmented Reality ist es von großer Bedeutung, dass virtuelle
Objekte möglichst realistisch in ein Kamerabild eingebettet werden. Nur
so ist es möglich, dem Nutzer eine immersive Erfahrung zu bieten. Dazu
gehört unter anderem, Verdeckung dieser Objekte korrekt zu behandeln.
Während schon verschiedene Ansätze existieren, dieses Verdeckungsproblem
zu beheben, wird in dieser Arbeit eine Lösung mittels Natural Image
Matting vorgestellt. Mit Hilfe einer Tiefenkamera wird das Kamerabild in
Vorder- und Hintergrund aufgeteilt und anschließend das virtuelle Objekt
im Bild platziert. Für Bereiche, in denen die Zugehörigkeit zu Vorder- oder
Hintergrund nicht eindeutig ist, wird anhand bekannter Pixel ein Transparenz-
Wert geschätzt. Es werden Methoden präsentiert, welche einen
Ablauf des Image Matting in Echtzeit ermöglichen. Zudem werden
Verbesserungsmöglichkeiten dieser Methoden präsentiert und gezeigt, dass
durch diese eine höhere Bildqualität für schwierige Szenen erreicht wird.
Die Dissertation bietet einen internationalen Vergleich von Gestaltungsmustern der Flexibilitätssteuerung von Unternehmen mit Schwerpunkt auf die Automobilindustrie. Vor dem Hintergrund unterschiedlicher nationaler institutioneller Systeme werden betriebliche Flexibilitätsstrategien analysiert und deren Hintergründe und Funktionsweisen detailliert erläutert. Die Analyse institutioneller Rahmenbedingungen erfolgt mittels der "Varieties of Capitalism". Die Eruierung von Flexibilitätsstrategien basiert auf einer internationalen Fallstudie.
Im Zentrum der Arbeit steht die Frage, inwiefern erwachsenenpädagogische Professionalität und Qualitätsmanagement als je eigene Zugänge der Qualitätssicherung im Kontext der Weiterbildung miteinander kompatibel sind.
Diese Frage wird seit den 1990er Jahren diskutiert und stellt sich gegenwärtig neu, u.a. angesichts branchenspezifischer Ansätze wie der Lernerorientierten Qualitätstestierung in der Weiterbildung (LQW).
Zur Beantwortung werden einschlägige Vertreter des Professionalitäts- und Qualitätsmanagementzugangs aus einer handlungstheoretischen Perspektive vergleichend im Hinblick auf ihre Handlungsordnungen gegenübergestellt. Grundlage bildet eine kategoriengeleitete, heuristisch angelegte Dokumentenanalyse sowohl von Grundlagentexten als auch von Normen- und Anforderungskatalogen.
Die Untersuchung zeigt, dass die Passung differenziert und jenseits dichotomisierender Gegenüberstellungen von Pädagogik bzw. Profession und Organisation oder von Pädagogik und Ökonomie zu beurteilen ist:
Zum einen wird die Heterogenität der Einzelansätze deutlich, welche sich in unterschiedlichem Umfang als kompatibel zueinander erweisen. Zum anderen werden entlang einzelner Handlungsdimensionen sowohl Anschluss- als auch Bruchstellen sichtbar.
Als ein weiterer zentraler Befund lässt sich festhalten, dass auch die Art der Spannungsverhältnisse zwischen erwachsenenpädagogischer Professionalität und Qualitätsmanagement unterschieden werden muss:
Während die Spannungen zwischen den gegensätzlichen methodischen Strategien (z.B. zwischen professionellem Fallbezug und organisationaler Standardisierung) gradueller Natur sind und „bearbeitet“ werden können, zeigen sich zwischen den programmatischen Zweck- und Aufgabenbestimmungen kategoriale Unterschiede und antinomische Konstellationen.
So verweisen das professionelle Leitprinzip der Teilnehmerorientierung sowie die für die Qualitätsmanagement-Ansätze maßgebliche Kunden- bzw. Lernerorientierung auf jeweils eigene sowie voneinander abweichende Vermittlungskonzepte, die nicht widerspruchsfrei zusammengeführt werden können.