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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.
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.
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.
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.
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.
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.
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.
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.