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The conservation of groundwater ecosystems requires an assessment and evaluation scheme that shows the state of the ecosystem. Consequently, faunal and microbial criteria are required for groundwater monitoring, in addition to physico-chemical analyses. To proof the adequacy of the application of groundwater organisms for the biological assessment of groundwater quality, an extensive sampling collection of various groundwater systems was accomplished between 2002 and 2009 in Germany. Key aspects were the examination of the indicator potential of groundwater communities towards surface-groundwater interactions and anthropogenic impacts, as well as the analysis of stygofaunal distribution patterns, as a base and reference for a faunal assessment scheme of groundwater systems. The sampling design considered local, regional, and biogeographic conditions. To test the indicator potential of groundwater organisms on a local and regional scale, groundwater systems in Nordrhein-Westfalen (NRW) and Baden-Württemberg (BW) were examined. The faunal and microbial data from unconsolidated aquifers (Erftgebiet, NRW) show the sensitivity of groundwater organisms against land use effects, e.g. extensive agriculture. Data analyses revealed positive correlations of organic material (estimated amount of detritus, TOC) and nitrate with faunal abundance, species richness, diversity and the proportions of stygoxene species. Moreover, the bacterial abundance and diversity in the groundwater of the Erftgebiet was high compared to oligotrophic groundwater systems, indicating an effect of surface influence due to agricultural land use. The groundwater colonization in the Alb-Donau-Kreis (BW) was analyzed for regional effects (landscape, type of aquifer, hydrogeology) and local effects (comparing single wells). The results show that the fauna reflects the strength of the hydrological exchange on different spatial scales. Furthermore, the fauna reflects the interaction of regional and local conditions. Accordingly, the diversity and abundance of groundwater organisms was influenced by the high connectivity of the karst and unconsolidated alluvial aquifers, the type of land use, covering layers of soil, the age of groundwater, and the sampling depths. In general, faunal and microbial data of the Alb-Donau-Kreis are characteristic for oligotrophic, oligoalimonic groundwaters. The large scale analyses of stygofaunal distribution patterns revealed significant biogeographical differences of the communities. These community patterns of the groundwater fauna do not coincide with existing classification schemes defined for surface landscapes or freshwater systems. The largest differences between faunal surface and subsurface distribution patterns were found between the groundwater of northern and southern Germany and the foothills of the central mountain ranges - all of them regions shaped by the last ice ages.
In accordance with the faunal data assessed in groundwater, four different stygoregions were defined that are populated by distinct faunal assemblages. These are 1) the "Northern lowlands", 2) the "Central mountain ranges", 3) the "South-western mountain ranges", and 4) the "Southern mountain ranges and northern alps". The study corroborates that stygofaunal and microbial communities are an adequate tool for the qualitative assessment and monitoring of groundwater ecosystems. The best indicators to detect anthropogenic impacts on groundwater ecosystems are the faunal diversity, abundance, the proportions of stygobitic (obligate groundwater species) and stygoxene species (species not obligate for groundwater), and the bacterial abundance. The development of an ecologically based groundwater assessment and management, is crucial for the conservation of our groundwater ecosystems and thus, healthy drinking water. The defintion of "stygoregions" is an important base for the development of an assessment and reference scheme for groundwater ecosystems. The assessment of the ecological state of groundwater systems must be conducted on local scale, because the strength of the local hydrological influence determines the amount of food and oxygen as well as stygoxene animals within the aquifer, and thus shapes the local groundwater communities. Nevertheless, information of the biogeographic and regional conditions is needed as a reference for the type of species and abundances that potentially can occur in certain groundwater systems.
In dieser Studienarbeit sollen verschiedene Routing-Lookup Algorithmen aufgelistet und verglichen werden, mit denen eine Routing-Tabelle erstellt und angepasst werden kann. Dazu werden hier nur dynamische Verfahren in Betracht gezogen. Allgemein wird die Funktionsweise einer Routing-Tabelle erklärt und drei Verfahren bzw. Algorithmen analysiert und bewertet. Die Algorithmen werden anhand von Beispielen erläutert und in einem abschließenden Kapitel gegenüber gestellt. Dabei werden die Vor- und Nachteile der einzelnen Verfahren aufgelistet.
Assessment of bat activity in agricultural environments and the evaluation of the risk of pesticides
(2013)
Although agriculture dominates with around 50% area much of Europe- landscape, there is virtually no information on how bats use this farmed environment for foraging. Consequently, little is known about effective conservation measures to compensate potential negative effects of agrarian management practice on the food availability for bats in this habitat. Moreover, there are currently no specific regulatory requirements to include bats in European Union risk assessments for the registration of pesticides since no information about pesticide exposure on this mammal group is available. To evaluate the potential pesticide exposure of bats via ingestion of contaminated insects, information about bat presence and activity in agricultural habitats is required. In order to examine bat activity on a landscape scale it was necessary to establish a suitable survey method. Contrary to capture methods, telemetry, and direct observations, acoustic surveys of bat activity are a logistically feasible and cost-effective way of obtaining bat activity data. However, concerns regarding the methodological designs of many acoustic surveys are expressed in the scientific literature. The reasons are the failing of addressing temporal and spatial variation in bat activity patterns and the limitations of the suitability of the used acoustic detector systems. By comparing different methods and detector systems it was found that the set up of several stationary calibrated detector systems which automatically trigger the ultrasonic recording has the highest potential to produce reliable, unbiased and comparable data sets on the relative activity of bats.
By using the proposed survey method, bat diversity and activity was recorded in different crops and semi-natural habitats in southern Rhineland-Palatinate. Simultaneously, the availability of aerial prey insects was studied by using light and sticky traps. In more than 500 sampling nights about 110,000 call sequences were acoustically recorded and almost 120,000 nocturnal insects were sampled. A total of 14 bat species were recorded, among them the locally rare and critically endangered northern bat (Eptesicus nilssonii) and the barbastelle (Barbastella barbastellum), all of them also occurring over agricultural fields. The agricultural landscape of southern Palatinate is dominated by vineyards, a habitat that was shown to be of low quality for most bat species because of the demonstrated low availability of small aerial insects. By surveying bat activity and food availably in a pair-wise design on several rain water retention ponds and neighbouring vineyards it was demonstrated that aquatic insect emergence in artificial wetlands can provide an important resource subsidy for bats. The creation of artificial wetlands would be a possibility to create important foraging habitats for bats and mitigate negative effects of management practice in the agricultural landscape.
In several other agricultural crops, however, high abundances of suitable prey insects and high bat activity levels, comparable or even higher than in the nearby forests and meadows known to be used as foraging habitats were demonstrated. Especially high bat activity levels were recorded over several fruit orchards and vegetable fields where insects were also present. Both crops are known for high pesticide inputs, and, therefore, a pesticide exposure through ingestion of contaminated insects can not be excluded. To follow the current risk assessment approach for birds and mammals pesticide residues were measured on bat-specific food items in an apple orchard following insecticide applications and bat activity was recorded in parallel. The highest residue values were measured on foliage-dwelling arthropods which may results in a reproductive risk for all bat species that, even to a small extent, include this prey group in their diet. The presence of bats in agricultural landscapes that form a majority of the land area in Europe but also on a global scale leads to exposure of bats by contaminated food and depletion of their food resources by pesticide use. So far conservation efforts for bats focussed on securing hibernation sites and the creation of artificial roost sites since especially the latter were thought to be limiting population growth. However the potential pesticide effects might be also crucial for the population persistence in agricultural landscapes of bats and need to be addressed adequately, especially in risk assessment procedures for the regulation of pesticides.
English prepositions take only a small proportion of the language but play a substantial role. Although prepositions are of course also frequently used in English textbooks for secondary school, students fail to incidentally acquire them and often show low achievements in using prepositions correctly. The strategy commonly employed by language instructors is teaching the multiple senses of prepositions by rote which fails to help the students to draw links between the different meanings in usage. New findings in Cognitive Linguistics (CL) suggest a different approach to teaching prepositions and thus might have a strong impact on the methodologies of foreign language teaching and learning on the aspects of meaningful learning. Based on the Theory of Domains (Langacker, 1987), the notions of image schemas (Johnson, 1987) as well as the Conceptual Metaphor Theory (Lakoff & Johnson, 1980), the present study developed a CL-inspired approach to teaching prepositions, which was compared to the traditional teaching method by an empirical study conducted in a German school setting. Referring to the participants from the higher track and the medium track, who are at different proficiency levels, the results indicate that the CL-inspired teaching approach improved students" performance significantly more than the traditional approach in all the cases for the higher track and in some cases for the medium track. Thus, these findings open up a new perspective of the CL-inspired meaningful learning approach on language teaching. In addition, the CL-inspired approach demonstrates the unification of the integrated model of text and picture comprehension (the ITPC model) in integrating the new knowledge with related prior knowledge in the cognitive structure. According to the learning procedure of the ITPC model, the image schema as visual image is first perceived through the sensory register, then is processed in the working memory by conceptual metaphor, and finally it is integrated with cognitive schemata in the long term memory. Moreover, deep-seated factors, such as transfer of mother tongue, the difficulty of teaching materials, and the influence of prior knowledge, have strong effects on the acquisition of English prepositions.
Augmented Reality (AR) is getting more and more popular. To augment information into the field of vision of the user using HMDs, e.g. front shields of a car, glasses, displays of a smartphone or tablets are the main use of AR technology. It is necessary to get the position and orientation (pose) of the camera in space to augment correctly.
Nowadays, this is solved with artificial markers. These known markers are placed in the room and the system is taught to this set up. The next step is to get rid of these artificial markers. If we are calculating the pose without such markers we are talking about marker-less tracking. Instead of artificial markers we will use natural objects in the real world as reference points to calculate the pose. Thus, this approach can be used flexibly and dynamically. We are no longer dependent on artificial markers but we need much more knowledge about the scenery to find the pose. This is compensated by technical actions and/or the user himself. However, both solutions are neither comfortable nor efficient for the usage of such a system. This is why marker-less 3D tracking is still a big field of research.
This sets the starting point for the bachelor thesis. In this thesis an approach is proposed that needs only a quantity of 2D Feature from a given camera image and a quantity of 3D Feature of an object to find the initial Pose. With this approach, we got rid of the technical and user assistance. 2D and 3D Features can be detected in any way you like.
The main idea of this approach is to build six correspondences between these quantities. With those we are able to estimate the pose. Each 3D Feature is mapped with the estimated pose onto image coordinates, whereby the estimated pose can be evaluated. Each distance is measured between the mapped 3D Feature and the associated 2D Feature. Each correspondency is evaluated and the results are summed up to evaluate the whole pose. The lower this summed up value is, the better the pose. It has been shown to have a correct pose with a value around ten pixels.
Due to lots of possibilities to build six correspondences between the quantities, it is necessary to optimize the building process. For the optimization we will use a genetic algorithm.
During the test case the system worked quite reliably. The hit rate was around 90% with a runtime of approximately twelve minutes. Without optimization it can take easily some years.
Die vorliegende Arbeit behandelt die Entwicklung einer Simulationsumgebung zur Darstellung von Objekten im Weltraum und ihrer gravitativen Wechselwirkung zu einander.
Vorab werden in Kapitel 1 Motivation und Zielsetzung der Arbeit erläutert, des Weiteren werden die verwendeten Werkzeuge benannt. Die nötigen astronomischen Grundlagen werden in Form von Begriffserklärungen und der Vorstellung der dieser Arbeit zugrunde liegenden physikalischen Gesetze in Kapitel 2 beschrieben.
Kapitel 3 befasst sich mit dem Aufbau der einzelnen Klassen. Hier wird insbesondere auf die Berechnung der Positionen und Geschwindigkeiten der simulierten Himmelskörper und den Aufbau und die Funktionsweise der verwendeten Elemente der Graphikengine Ogre3D eingegangen.
Im Kapitel 4 wird der Einsatz des Werkzeugs 3ds Max zur Erstellung der Geometrieobjekte und Materialien erläutert.
Abschließend wird in Kapitel 5 ein Fazit gezogen und mögliche zukünftige Erweiterungen erwogen.
This habilitation thesis deals with the effects of toxicants on freshwater ecosystems and considers different toxicant classes (pesticides, organic toxicants, salinity) and biotic endpoints (taxonomic community structure, trait community structure, ecosystem functions).
The thesis comprises 12 peer-reviewed international publications on these topics. All of the related studies rely on mesocosm or field investigations, or the analysis of field biomonitoring or chemical monitoring data. Publications I and II are devoted to passive sampling of a neonicotinoid insecticide and polycyclic aromatic hydrocarbons (PAHs), respectively. They show that biofouling and a diffusion-limiting membrane can reduce the sampling rate of the pulsed insecticide exposure and that receiving phases of different thicknesses can be used to assess the kinetic regime during field deployment of passive samplers. Publications III to VI mainly focus on trait-based approaches to reveal toxicant effects on invertebrates in streams. An overview on the framework and several applications of a trait-based approach to detect effects of pesticides (SPEARpesticides index) are given in publication III. Publication IV describes the development of a trait database for South-East Australian stream invertebrates and its successful application in the adaptation of SPEARpesticides as well as the development of a salinity index. Moreover, a conceptual model for the future development of trait-based biomonitoring indices is proposed. Publication V reports a mesocom study on the effects of a neonicotinoid insecticide on field-realistic invertebrate communities. The insecticide had long-term effects on the invertebrate communities, which were only detected when grouping the taxa according to their life-history traits. A comprehensive field study employing different pesticide sampling methods including passive sampling and biomonitoring of the invertebrate and microbial communities is presented in publication VI. The study did not find pesticide-induced changes in the microbial communities, but detected adverse effects of current-use pesticides on the invertebrate communities using the trait-based SPEARpesticides index. This index is also applied in a meta-analysis on thresholds for the effects of pesticides on invertebrate communities in publication VII. It is shown that there is a similar dose-response relationship between SPEARpesticides and pesticide toxicity over different biogeographical regions and continents. In addition, the thresholds for effects of pesticides are lower than derived from most mesocosm studies and than considered in regulatory pesticide risk assessment. The publications VIII to X use statistical data analysis approaches to examine effects of toxicants in freshwater ecosystems. Using governmental monitoring data on 331 organic toxicants monitored monthly in 4 rivers over 11 years, publication VIII finds that organic toxicants frequently occurred in concentrations envisaging acute toxic effects on invertebrates and algae even in large rivers. Insecticides and herbicides were the chemical groups mainly contributing to the ecotoxicological risk. Publication IX introduces a novel statistical method based on a similarity index to estimate thresholds for the effects of toxicants or other stressors on ecological communities. The application of the method for deriving thresholds for salinity, heavy metals and pesticides in streams is presented in three case studies. Publication X tackles the question of interactive effects between different toxicants using data from a field study on stream invertebrates in 24 sites of South-East Australia. Both salinity and pesticides exhibited statistically significant effects on the invertebrate communities, but no interaction between the stressors was found. Moreover, salinity acted on a higher taxonomical level than pesticides suggesting evolutionary adaptation of stream invertebrates compared to pesticide stress. Publications XI and XII concentrate on the effects of toxicants on biodiversity, ecosystem functions and ecosystem services, with publication XI summarising different studies related to the ecological risk assessment for these endpoints. A field study on the effects of pesticides and salinity on the ecosystem functions of allochthonous organic matter decomposition, gross primary production and ecosystem respiration is presented in publication XII. Both pesticides and salinity reduced the breakdown of allochthonous organic matter, whereas no effects on the other ecosystem functions were detected. A chapter following these publications synoptically discusses all studies of this habilitation thesis and draws general conclusions. It is stressed that in order to advance the understanding of effects of toxicants on freshwater ecosystems more ecological realism is needed in ecotoxicological approaches and that the spatiotemporal extent of toxicant effects needs more scrutiny.
This study investigates crowdfunding, a new form of financing projects. In the past years more and more crowdfunding platforms emerged. The main question is if crowdfunding is able to compete with the traditional types of financing social projects. The history and development of crowdfunding is presented in this paper. The different crowdfunding models are explained. An overview of German crowd funding platforms is presented. Based on successful social crowdfunding projects a list of key success factors is listed and described. In a case study a concept for financing a social project through crowdfunding is developed upon the previous studies.
Worldwide one third to one half of the freshwater crayfish species are threatened with population decline or extinction. Besides habitat deterioration, pollution, and other man-made environmental changes, invasive species and pathogens are major threats to the survival of European crayfish species. Freshwater crayfish are the largest freshwater invertebrates and strongly influence the structure of food webs. The disappearance of crayfish from a water body may change the food web and could have dramatic consequences for an ecosystem.rnOne goal in modern species conservation strategies is the conservation of genetic diversity, since genetic diversity is an advantage for the long-term survival of a species. The main aim of my thesis was to reveal the genetic structure and to identify genetic hotspots of the endangered noble crayfish (Astacus astacus) throughout Europe (part 1 of my thesis). Since the most significant threat to biodiversity of European crayfish species is the crayfish plague pathogen Aphanomyces astaci I studied new aspects in the distribution of A. astaci (part two of my thesis). The results serve as a basis for future conservation programs for freshwater crayfish. In the first part of my thesis I conducted a phylogeographic analysis of noble crayfish using mitochondrial DNA and nuclear microsatellite data. With these methods I aimed to identify its genetic hotspots and to reconstruct the recolonization history of central Europe by this species. I detected high genetic diversities in southestern Europe indicating that noble crayfish outlasted the cold climate phases during the Pleistocene in this region (Appendix 1). Because of the high genetic diversity found there, southeastern Europe is of particular importance for the conservation of noble crayfish. The mitochondrial DNA analysis points to a bifurcated colonization process from the eastern Black Sea basin to a) the North Sea and to b) the Baltic Sea basin (Appendix 2). A second independent refugium that was localized on the Western Balkans did not contribute to the colonization of central Europe. Furthermore, I found that the natural genetic structure is dissolved, probably due to the high human impact on the distribution of noble crayfish (e.g. artificial translocation). In the second part of this thesis using real-time PCR I identified calico crayfish (Orconectes immunis) as the fourth North American crayfish species to be carrier of the agent of the crayfish plague (Appendix 3). Furthermore I detected the crayfish plague pathogen in American spiny-cheek crayfish (Orconectes limosus) and native narrow-clawed crayfish (Astacus leptodactylus) in the lower Danube in Romania (Appendix 4). The distribution of infected spiny-cheek crayfish poses a threat to the native biodiversity in southeastern Europe and shows the high invasion potential of this crayfish species. Moreover, I found that even the native narrow-clawed crayfish in the Danube Delta, about 970 km downstream of the current invasion front of American crayfish, is a carrier of A. astaci (Appendix 5). This finding is of high importance, as the native species do not seem to suffer from the infection. In Appendix 6 I elucidate demonstrate that the absence of the crayfish plague agent is the most likely explanation for the coexistence of populations of European and American crayfish in central Europe. In my thesis I show that the common assumption that all North American crayfish are carrier of A. astaci and that all native crayfish species die when infected with A. astaci does not hold true. The studies presented in my thesis reveal new aspects that are crucial for native crayfish conservation: 1) The genetic diversity of noble crayfish is highest in southeastern Europe where noble crayfish outlasted the last glacial maximum in at least two different refugia. 2) Not all American crayfish populations are carrier of A. astaci and 3) not all Europen crayish populations die shortly after being infected with the crayfish plague pathogen.rnTo conserve native crayfish species and their (genetic) diversity in the long term, further introductions of American crayfish into European waters must be avoided. However, the introduction will only decrease if the commercial trade with non-indigenous crayfish species is prohibited.
Infinite worlds
(2013)
This work is concerned with creating a 2D action-adventure with roleplay elements. It provides an overview over various tasks of the implementation. First, the game idea and the used gamemechanism are verified and a definfinition of requirements is created. After introducing the used framework, the software engineering concept for realization is presented. The implementation of control components, game editor, sound and graphics is shown. The graphical implementation pays special attention to the abstraction of light and shadow into the 2D game world.
The goal of this Bachelor thesis was programming an existig six-legged robot, which should be able to explore any environment and create a map of it autonomous. A laser scanner is to be integrated for cognition of this environment. To build the map and locate the robot a suitable SLAM(Simultaneous Localization and Mapping) technique will be connected to the sensor data. The map is reported to be the robots base of path planning and obstancle avoiding, what will be developed in the scope of the bachelor thesis, too. Therefore both GMapping and Hector SLAM will be implemented and tested.
An exploration algorithm is described in this bachelor thesis for exploring the robots environment. The implementation on the robot takes place in the space of ROS(Robot Operating System) framework on a "Raspberry Pi" miniature PC.
The search for scientific literature in scientific information systems is a discipline at the intersection between information retrieval and digital libraries. Recent user studies show two typical weaknesses of the classical IR model: ranking of retrieved and maybe relevant documents and the language problem during the query formulation phase. At the same time traditional retrieval systems that rely primarily on textual document and query features are stagnating for years, as it could be observed in IR evaluation campaigns such as TREC or CLEF. Therefore alternative approaches to surpass these two problem fields are needed. Two different search support systems are presented in this work and evaluated with a lab evaluation using the IR test collection GIRT and iSearch with 150 and 65 topics, respectively. These two systems are (1) a query expansion that is based on the analysis of co-occurrences of document attributes and (2) a ranking mechanism that applies informetric analysis of the productivity of information producers in the information production process. Both systems were compared to a baseline system using the Solr search engine. Both methods showed positive effects when applying additional document attributes like author names, ISSN codes and controlled terms. The query expansion showed an improvement in precision (bpref +12%) and in recall (R +22%).
he alternative ranking methods were able to compete with the baseline for author names and ISSN codes and were able to beat the baseline by using controlled terms (MAP +14%). A clear negative influence was seen when using entities like publishers or locations. Both methods were able to generate a substantially different sorting of the result set, measured using Kendall. So, additional to the improved relevance in the result list, the user can get a new and different view on the document set. Query expansion using author names, ISSN codes and thesaurus terms showed great potential that lies within the rich metadata sets of digital library systems. The proposed ranking methods could outperform standard relevance ranking methods after they were filtered by the existence of a so-called power law. This showed that the proposed ranking methods cannot be used universally in any case but require specific frequency distributions in the metadata. A connection between the underlying informetric laws of Bradford, Lotka and Zipf is made clear. The evaluated methods were implemented as interactive search supporting systems that can be used in an interactive prototype and the social science digital library system Sowiport. Besides that, the methods are adaptable to other systems and environments using a free software framework and a web API.
Chemical plant protection is an essential element in integrated pest management and hence, in current crop production. The use of Plant Protection Products (PPPs) potentially involves ecological risk. This risk has to be characterised, assessed and managed.
For the coming years, an increasing need for agricultural products is expected. At the same time, preserving our natural resources and biodiversity per se is of equally fundamental importance. The relationship of our economic success and cultural progress to protecting the environment has been made plain in the Ecosystem Service concept. These distinct 'services' provide the foundation for defining ecological protection goals (Specific Protection Goals, SPGs) which can serve in the development of methods for ecological risk characterisation, assessment and management.
Ecological risk management (RM) of PPPs is a comprehensive process that includes different aspects and levels. RM is an implicit part of tiered risk assessment (RA) schemes and scenarios, yet RM also explicitly occurs as risk mitigation measures. At higher decision levels, RM takes further risks, besides ecological risk, into account (e.g., economic). Therefore, ecological risk characterisation can include RM (mitigation measures) and can be part of higher level RM decision-making in a broader Ecosystem Service context.
The aim of this thesis is to contribute to improved quantification of ecological risk as a basis for RA and RM. The initial general objective had been entitled as "… to estimate the spatial and temporal extent of exposure and effects…" and was found to be closely related to forthcoming SPGs with their defined 'Risk Dimension'.
An initial exploration of the regulatory framework of ecological RA and RM of PPPs and their use, carried out in the present thesis, emphasised the value of risk characterisation at landscape-scale. The landscape-scale provides the necessary and sufficient context, including abiotic and biotic processes, their interaction at different scales, as well as human activities. In particular, spatially (and temporally) explicit landscape-scale risk characterisation and RA can provide a direct basis for PPP-specific or generic RM. From the general need for tiered landscape-scale context in risk characterisation, specific requirements relevant to a landscape-scale model were developed in the present thesis, guided by the key objective of improved ecological risk quantification. In principle, for an adverse effect (Impact) to happen requires a sensitive species and life stage to co-occur with a significant exposure extent in space and time. Therefore, the quantification of the Probability of an Impact occurring is the basic requirement of the model. In a landscape-scale context, this means assessing the spatiotemporal distribution of species sensitivity and their potential exposure to the chemical.
The core functionality of the model should reflect the main problem structures in ecological risk characterisation, RA and RM, with particular relationship to SPGs, while being adaptable to specific RA problems. This resulted in the development of a modelling framework (Xplicit-Framework), realised in the present thesis. The Xplicit-Framework provides the core functionality for spatiotemporally explicit and probabilistic risk characterisation, together with interfaces to external models and services which are linked to the framework using specific adaptors (Associated-Models, e.g., exposure, eFate and effect models, or geodata services). From the Xplicit-Framework, and using Associated-Models, specific models are derived, adapted to RA problems (Xplicit-Models).
Xplicit-Models are capable of propagating variability (and uncertainty) of real-world agricultural and environmental conditions to exposure and effects using Monte Carlo methods and, hence, to introduce landscape-scale context to risk characterisation. Scale-dependencies play a key role in landscape-scale processes and were taken into account, e.g., in defining and sampling Probability Density Functions (PDFs). Likewise, evaluation of model outcome for risk characterisation is done at ecologically meaningful scales.
Xplicit-Models can be designed to explicitly address risk dimensions of SPGs. Their definition depends on the RA problem and tier. Thus, the Xplicit approach allows for stepwise introduction of landscape-scale context (factors and processes), e.g., starting at the definitions of current standard RA (lower-tier) levels by centring on a specific PPP use, while introducing real-world landscape factors driving risk. With its generic and modular design, the Xplicit-Framework can also be employed by taking an ecological entity-centric perspective. As the predictive power of landscape-scale risk characterisation increases, it is possible that Xplicit-Models become part of an explicit Ecosystem Services-oriented RM (e.g., cost/benefit level).
Polsearchine: Implementation of a policy-based search engine for regulating information flows
(2013)
Many search engines regulate Internet communication in some way. It is often difficult for end users to notice such regulation, as well as obtaining background information for it. Additionally, the regulation can usually be circumvented easily. This bachelor thesis presents the prototypical metasearch engine "Polsearchine" for addressing these weaknesses. Its regulation is established through InFO, a model for regulating information flows developed by Kasten and Scherp. More precisely, the extension for regulating search engines SEFCO is being used. For retrieving search results, Polsearchine uses an external search engine API. The API can be interchanged easily to make this metasearch engine independent from one specific API.
ERP market analysis
(2013)
Der aktuelle ERP Markt wird dominiert von den fünf größten Anbietern SAP, Oracle, Microsoft, Infor und Sage. Da der Markt und die angebotenen Lösungen vielfältig sind, bedarf es einer fundierten Analyse der Systeme. Die Arbeit beleuchtet dabei anhand ausgesuchter Literatur und Kennzahlen der verschiedenen Unternehmen die theoretische Seite der angebotenen Lösungen der fünf großen ERP Anbieter. Daneben wird die Nutzung der Systeme in der Praxis anhand der Befragung von sechs Anwendern analysiert und die Systeme miteinander verglichen.
Ziel der Arbeit ist es, dass die Forschungsfragen beantwortet werden und dass es bezogen auf die Systeme dem Leser der Arbeit ersichtlich wird, welches ERP System für welche Unternehmensbranche und Unternehmensgröße am besten geeignet ist.
Des Weiteren gibt die Arbeit Aufschluss darüber, welche Trends für ERP Systeme für die Zukunft zu erwarten sind und welche Herausforderungen sich dadurch für die Unternehmen stellen.
This thesis describes the conception, implementation and evaluation of a collaborative multiplayer game for preschoolers for mobile devices.
The main object of this thesis is to find out, if mobile devices like smartphones and tablet computers are suitable for the interaction of children. In order to develop this kind of game relevant aspects were researched. On this basis a game was designed which was finally tested by preschoolers.
The polysaccharide hydration phenomenon is nowadays the subject of intense research. The interaction of native and modified polysaccharides and polysaccharides-based bioconjugates with water has an important influence on their functional behaviour. Notwithstanding that the hydration phenomenon has been studied for decades, there is still a lack of awareness about the influence of hydration water on the polysaccharide´s structure and consequences for industrial or medicinal applications. The hydration of polysaccharides is often described by the existence of water layers differing in their physical properties depending on the distance from the polysaccharide. Using the differential scanning calorimetry (DSC) such water layers were categorized according their properties upon cooling in hyaluronan (HYA, sodium salt of ß-1,4-linked units of ß-1,3-linked D-glucuronic acid and N-acetyl-D-glucosamine), a model polysaccharide in the present work. The amount of non-freezing water, i.e. water in close proximity of HYA chain which does not freeze et all, was determined around 0.74gH2O/gHYA for HYA with molecular weight from 100 to 740kDa and 0.84gH2O/gHYA for molecular weight of 1390kDa. The amount of freezing-bound water, the water pool which is affected by presence of HYA but freezes, was determined in the range from 0.74 to 2gH2O/gHYA. Above this value only non-freezing and bulk water are present since melting enthalpy measured above this concentration reached the same value as for pure water. Since this approach suffers from several experimental problems, a new approach, based on the evaporation enthalpy determination, was suggested. The analysis of the evaporation enthalpies revealed an additional process associated with apparent energy release taking part below the water content of 0.34gH2O/gHYA. Existence of this phenomenon was observed also for protonated form of HYA. The existence of energy compensating process was confirmed with the Kissinger-Akahira-Sunose method which allowed determination of actual water evaporation/desorption enthalpies in all stages of the evaporation process. In fact, the apparent evaporation enthalpy value increased until water content of 0.34gH2O/gHYA, and then dropped down to lower values which were, still higher than the value of the pure water evaporation enthalpy. By the use of time domain nuclear magnetic resonance (TD-NMR) technique it was revealed that this phenomenon is the plasticisation of HYA.
Further, it was revealed that the non-freezing water determined by the use of DSC consists of two water fractions, i.e. 15% of water structurally integrated, interacting directly with polar sites, and 85% of water structurally restricted, embedded in-between the HYA chains. The occurrence of plasticisation concentration close to equilibrium moisture content provided the possibility to influence the HYA physical structure during the drying. In this way three samples of native HYA, dried under various conditions were prepared and their physical properties were analyzed. The samples differed in kinetics of rehydration, plasticisation concentration, glass transitions, and morphology. The properties of water pool were studied in solutions of 10"25mg HYA/mL as well. The fast filed cycling (FFC) NMR relaxometry showed the existence of three water fractions which correlation times spanned from 10"6 to 10"10 seconds, progressively decreasing in dependency on its distance from HYA chain. The formation of a weak and transient intramolecular water bridge between HYA chains was observed. It was shown that, unlike the inorganic electrolytes, polyelectrolytes hydration is a dynamic process which reflects not only the technique used for the analysis, experimental conditions but also the conformation of the polysaccharide and its "thermal" and "hydration" history.
It was demonstrated that some native polysaccharide structures can be easily modified by manipulation of preparation conditions, giving fractions with specific physicochemical properties without necessity of any chemical modification.
This work deals with the migration of software systems towards the use of the character set defined in the Unicode standard. The work is performed as a case study on the document-management-system PROXESS. A conversion process will be designed that defines the working-steps of the migration for the entire system as well as an arbitrary decomposition of the system into individual modules. The working-steps for each module can be performed chronologically independent of each other to a great extend. For the conversion of the implementation, an approach of automatic recognition of usage patterns is applied. The approach aims at searching the abstract syntax tree for sequences of program instructions that can be assigned to a certain usage pattern. The usage pattern defines another sequence of instructions that acts as an sample solution for that usage pattern. The sample solution demonstrates the Unicode-based management of strings for that usage pattern. By applying a transformation rule, the original sequence of instructions is transferred to the sequence of instructions exposed by the sample solution of the related usage pattern. This mechanism is a starting point for the development of tools that perform this transformation automatically.
This bachelor thesis deals with the concept of a smartphone application for emergencies. It describes the basic problem and provides a conceptual approach.
The core content of this thesis is a requirement analysis of the newly to be designed emergency application. Furthermore the functional and non-functional requirements such as usability are specified to give insights for the concept of the application. In addition, single sub-functions of the mHealth applications of the University Koblenz which exists or are still under construction can be integrated in the future emergency application. Based on the catalog of requirements a market analysis for strengths and weaknesses of existing emergency application systems is realized. In the to-be concept the findings were summarized and possible architectural sketches for future emergency applications were given. Furthermore, one conclusion of dealing with this topic is that a design alone is not sufficient to guarantee a good working app. That is why the requirements for the thesis were expanded by the connection to and integration of rescue centers in the architecture of the emergency app.
At the end of the thesis, the reader will receive a comprehensive overview of the provision of emergency data to the rescue control centers by different transmission channels. Furthermore, conditions for the system requirements are also presented as possible scenarios of the architecture of the whole system of the emergency application. The generic and modular approach guarantees that the system is open for future development and integration of functions of other applications.
This dissertation investigates the usage of theorem provers in automated question answering (QA). QA systems attempt to compute correct answers for questions phrased in a natural language. Commonly they utilize a multitude of methods from computational linguistics and knowledge representation to process the questions and to obtain the answers from extensive knowledge bases. These methods are often syntax-based, and they cannot derive implicit knowledge. Automated theorem provers (ATP) on the other hand can compute logical derivations with millions of inference steps. By integrating a prover into a QA system this reasoning strength could be harnessed to deduce new knowledge from the facts in the knowledge base and thereby improve the QA capabilities. This involves challenges in that the contrary approaches of QA and automated reasoning must be combined: QA methods normally aim for speed and robustness to obtain useful results even from incomplete of faulty data, whereas ATP systems employ logical calculi to derive unambiguous and rigorous proofs. The latter approach is difficult to reconcile with the quantity and the quality of the knowledge bases in QA. The dissertation describes modifications to ATP systems in order to overcome these obstacles. The central example is the theorem prover E-KRHyper which was developed by the author at the Universität Koblenz-Landau. As part of the research work for this dissertation E-KRHyper was embedded into a framework of components for natural language processing, information retrieval and knowledge representation, together forming the QA system LogAnswer.
Also presented are additional extensions to the prover implementation and the underlying calculi which go beyond enhancing the reasoning strength of QA systems by giving access to external knowledge sources like web services. These allow the prover to fill gaps in the knowledge during the derivation, or to use external ontologies in other ways, for example for abductive reasoning. While the modifications and extensions detailed in the dissertation are a direct result of adapting an ATP system to QA, some of them can be useful for automated reasoning in general. Evaluation results from experiments and competition participations demonstrate the effectiveness of the methods under discussion.
This paper consists of the observation of existing first aid applications for smartphones and comparing them to a first aid application developed by the University of Koblenz called "Defi Now!". The main focus lies on examining "Defi Now!" in respect to its usability based on the dialogue principles referring to the seven software ergonomic principles due to the ISO 9241-110 standard. These are known as suitability for learning, controllability, error tolerance, self-descriptiveness, conformity with user expectations, suitability for the task, and suitability for individualization.
Therefore a usability study was conducted with 74 participants. A questionnaire was developed, which was to be filled out by the test participants anonymously. The test results were used for an optimization of the app referring its' usability.
Diese Bachelor-Thesis beschäftigt sich mit der Entwicklung eines Programms, welches den Zahnarzt durch die AR bei seiner Behandlung am Patienten unterstützen soll. Um eine angemessene theoretische Grundlage zu schaffen, wird zunächst der aktuelle Stand der Technik erläutert, der für dieses Projekt relevant ist. Daraufhin werden mögliche zukünftige Technologien vorgestellt, welche die hypothetische Basis dieser Arbeit darstellen. In dem darauffolgenden Unterkapitel wird die Auswahl der Systeme erläutert, die für dieses Projekt verwendet wurden. Der Hauptteil beschäftigt sich zunächst mit dem Vorgehen in der Vorbereitungs- und Planungsphase, um daraufhin den Programmablauf der Applikation sukzessiv vorzustellen. Dabei wird auch auf die Probleme eingegangen, die während des Programmierens entstanden sind. In dem reflektierenden Auswertungsteil werden Verbesserungsvorschlägen und Zusatzfunktionen für das geschriebene Programm präsentiert.
Kapitel 1 führt - unter Berücksichtigung gesamtgesellschaftlicher Tendenzen im Hinblick auf verschiedene Lebensformen - zunächst in das Thema ein. Auf Basis der Tatsache geringer Scheidungsraten von Managerehen werden unterschiedliche Annahmen formuliert, die für die Ehestabilität dieser Paare eine Rolle spielen könnten.
Im Weiteren werden hier wesentliche Fragestellungen zum Thema der vorliegenden Arbeit und deren Zielsetzung begründet. Kapitel 2 fasst den aktuellen Forschungsstand zusammen. Bisherige Untersuchungsergebnisse zum Themenfeld Manager und deren Ehen sowie auch der Ehestabilitätsforschung werden hier vorgestellt und auf ihre Relevanz hin befragt. Ziel ist es, bereits gewonnene Ergebnisse nach ihrer Bedeutung für diese Arbeit zu bewerten und entsprechende Fragestellungen daraus abzuleiten. Kapitel 3 setzt sich mit theoretischen Ansätzen zur Erklärung von Ehestabilität auseinander. Vor dem Hintergrund verschiedener Handlungsmodelle stellt sich die Frage, ob die Stabilität von Managerehen das Ergebnis von wertorientiertem, zweckorientiertem oder gar traditionalem Handeln ist. Insbesondere werden hier der kultursoziologische Ansatz von Schreiber und die Rational Choice Theorie von Esser als maßgebliche theoretische Grundlage für den Leitfaden und die Auswertung des empirischen Materials vorgestellt und erläutert. Im Anschluss daran erklärt Kapitel 4 die Voraussetzungen und den Ablauf der Erhebung der Daten und beschreibt die Paare des vorliegenden Samples. Als Methode der Befragung wurde das Leitfadeninterview gewählt, welches begründet und von seiner Konzeption wie auch seinen Inhalten her beschrieben wird. Die Erläuterung zur Durchführung der Interviews und zur Methode der Analyse der Gespräche bilden den Abschluss dieses Kapitels. Kapitel 5 führt sodann in das vorliegende empirische Material ein. Es dient der Beschreibung der interviewten Paare in der Darstellungsform von insgesamt zehn Paarportraits. Ziel hierbei ist zum einen, die Beziehungswelt der Paare abzubilden, zum anderen zu zeigen, dass es bei allen Befragten prägnant wiederkehrende Strukturelemente innerhalb der Beziehung gibt. Diese geben einen ersten Hinweis auf die besonderen Stabilitätsfaktoren von Managerehen. Das folgende Kapitel 6 fasst die Erfolgsfaktoren ehelicher Stabilität der befragten Paare zusammen. Es kann aufzeigen, wie die Faktoren Heiratsmotivation, Rollenverteilung, Paarinteraktion, Statussymbole, soziales Umfeld, Beziehungswünsche und -visionen von den Paaren beschrieben werden und welche Rolle sie im Hinblick auf die Ehestabilität der Paare spielen. Hier wird deutlich dass es bei den Aussagen der Befragten große Strukturähnlichkeiten gibt, die es erlauben von einem Sondertypus "stabile Ehe" zu sprechen. In einer zusammenfassenden Beschreibung wird herausgestellt, welche Merkmale diesen besonderen Typus kennzeichnen und was ihn letztendlich charakterisiert. Managerehepaare leben in einer erfolgreichen Lebensform zusammen. Sie stellen einen Sondertypus unter den bisher bekannten Lebensformen dar. Das Schlusskapitel 7 fasst die Ergebnisse dieser Arbeit zusammen und pointiert sie in der Konstruktion einer managerspezifischen Lebensform, für die der Name LTA (Living Together Apart)20 gewählt wurde.
In this thesis, a first prototype of a mobile instruction device with mixed reality (MR) funktionality is developed. This system shall be capable to support training on the job through interaction with the work item. The concept corresponds to a didactic approach presented by Martens-Parree that combines constructivism with situated learning. As an application example, the training of glider pilots checked out on a new type was chosen. Whether the MR device could increase the competence, or facilitiate the completion of certain tasks, was examined in a survey with fifteen testers. The results of the study show that in general, the didactic approach of Martens-Parree is valid. While an increase in fact knowledge has been observed, it was not (yet) possible to demonstrate an increase in skills with respect to the work tasks.
The purpose of this bachelor- thesis is to teach Lisa - a robot of the university of Koblenz- AGAS department developed for participation in the @home league of the RoboCup - to draw. This requires the expansion of the robbie software framework and the operation of the robot- hardware components. Under consideration of a possible entry in the Open Challenge of the @home RoboCup, the goals are to detect a sheet of paper using Lisa- visual sensor, a Microsoft Kinect and draw on it using her Neuronics Katana robot arm. In addition, a pen mounting for the arm- gripper has to be constructed.
Outlined within this thesis are the procedures utilized to convert an image template into movement of the robotic arm, which in turn leads to drawing of a painting by the pen attached to the arm on a piece of paper detected by the visual sensor through image processing. Achieved were the parsing and drawing of an object made up of an indefinite amount of straight lines from a SVG-file onto a white sheet of paper, detected on a slightly darker surface and surrounded by various background objects or textures.
Das Kommunikationsverhalten hat sich in den letzten Jahren durch die Smartphonenutzung verändert. Die Nutzer kommunizieren oft nur noch über den elektronischen Weg. Die persönliche Kommunikation, außerhalb des Smartphones, nimmt ab. Das Umfeld gerät unterdessen in Vergessenheit. In der vorliegenden Arbeit werden verschiedene Spielkonzepte entwickelt, welche die Kommunikation steigern sollen. Realisiert wird der Ansatz in einer prototypischen Stadtführer-App, nach den Spielkonzepten von "Scotland Yard" und "Schnitzeljagd". Während der Nutzung müssen die Spieler verschiedene Aufgaben lösen. Welches Spielkonzept sich in Bezug auf die Kommunikationsförderung am besten eignet, wird in einer Evaluation analysiert.
Recipients" youtube comments to the five most successful songs of 2011 and 2012 are tested for nostalgic content. These nostalgic relevant comments are analyzed by content and finally interpreted. It shall be found out, whether nostalgic music content is a factor for success. By using the uses and gratifications theory the recipients" purpose of consuming nostalgic-evoking music will be identified. Music is a clearly stronger trigger for evoking nostalgia than the music video whereas nostalgia triggers positive and/or negative affect. Furthermore personal nostalgia is much more evident than historical nostalgia. Moreover the lyrics have a considerably higher potential to elicit nostalgia than any other song units. Persons and momentous events are the most frequent objects in personal nostalgic reverie. The purpose of consuming nostalgic music is the intended evocation of positive and/or negative affect. Hence nostalgia in music seems to satisfy certain needs and it can be assumed that nostalgia is a factor of success in music industry.
Human detection is a key element for human-robot interaction. More and more robots are used in human environments, and are expected to react to the behavior of people. Before a robot can interact with a person, it must be able to detect it at first. This thesis presents a system for the detection of humans and their hands using a RGB-D camera. First, a model based hypotheses for possible positions of humans are created to recognize a person. By using the upper parts of the body are used to extract, new features based on relief and width of a person- head and shoulders are extracted. The hypotheses are checked by classifying the features with a support vector machine (SVM). The system is able to detect people in different poses. Both sitting and standing humans are found, by using the visible upper parts of the person. Moreover, the system is able to recognize if a human is facing or averting the sensor. If the human is facing the sensor, the color information and the distance between hand and body are used to detect the positions of the person- hands. This information is useful for gestures recognition and thus can further enhances human-robot interaction.
We present the conceptual and technological foundations of a distributed natural language interface employing a graph-based parsing approach. The parsing model developed in this thesis generates a semantic representation of a natural language query in a 3-staged, transition-based process using probabilistic patterns. The semantic representation of a natural language query is modeled in terms of a graph, which represents entities as nodes connected by edges representing relations between entities. The presented system architecture provides the concept of a natural language interface that is both independent in terms of the included vocabularies for parsing the syntax and semantics of the input query, as well as the knowledge sources that are consulted for retrieving search results. This functionality is achieved by modularizing the system's components, addressing external data sources by flexible modules which can be modified at runtime. We evaluate the system's performance by testing the accuracy of the syntactic parser, the precision of the retrieved search results as well as the speed of the prototype.
Structure of soil organic matter (SOM) is a hot topic of discussion among scientific community for several decades. The mostly discussed models, among many, are polymer model and supramolecular model. While the former considers SOM as macromolecules consisting of amorphous and crystalline domains, the latter explains SOM as a physicochemical entity dominated by weak hydrophobic and H-bond interactions in the secondary level, which holds individual molecules of primary structure together. The weak forces in secondary level impart characteristic mobility of SOM. Very important consequence of this multidimensional formulation is that physicochemical structure plays a crucial role in most biogeochemical functions of SOM, apart from the chemical composition. Recently introduced concept of cation and water molecule mediated bridges between OM molecular segments (CaB and WaMB, respectively) evolved from physicochemical understanding of SOM structure. Even though several indirect evidences were produced for CaB and WaMB during last years, no clear-cut understanding of these processes has been achieved yet. Experimental difficulty due to overlapping effects of equally important CaB-governing parameters such a pH and competing cations raises huge challenge in investigating CaB-related influences. This thesis, therefore, aims to validate an experimental set-up for inducing CaB within OM structures and assessing it from various chemical and physicochemical aspects.
The method involved removal of omnipresent cations and adjustment of pH before cation addition. This helped to separate pH effects and cation effects. Based on results obtained on two different types of organic matter, it can be deduced that multivalent cations can cross-link SOM, given that functional group density of the SOM material is enough for the functional groups to be arranged in sufficient spatial proximity to each other. Physicochemical structural reorganisation during aging causes formation of more and/or stronger CaB and WaMB. As for inducing CaB directly after cation treatment, cationic size and valency were found determinant also for aging effect. A strongly cross-linked system in the beginning is less vulnerable to structural changes and undergoes aging with lower intensity, than an initially weakly cross-linked system. Responsible for the structural changes is, the inherent mobility of SOM within its physicochemical assemblage. Thus the information on structural requirement of CaB and its consequences on OM matrix rigidity will help to obtain insight into the physicochemical SOM structure. Additionally, organic matter quality (assessed by thermal analysis) and pore structure of SOM formed in a set of artificial soils showed that mineral materials are important for the chemical nature of SOM molecules, but not for the physical structure of organo-mineral associations, at least after several months of SOM development.
Furthermore, nanothermal analysis using atomic force microscopy (AFM-nTA) was implemented in soils for the first time to reveal nanoscale thermal properties and their spatial distribution in nano- and micrometer scales. This helped to identify physicochemical processes, such as disruption of WaMB, in low-organic soils, in which bulk methods fail due to their low sensitivity. Further, various types of materials constituting in soils were distinguished with high resolution by advanced application of the method, in combination with other AFM parameters. Attempts were done to identify various materials, with the usage of defined test materials. Above all, the method is potent to reveal microspatial heterogeneity on sample surfaces, which could help understanding process-relevant hotspots, for example.
This thesis thus contributes to the scientific understanding on physicochemical structural dynamics via cross-linking by cations and via nanoscale thermal properties. Direct investigation on CaB demonstrated here will potentially help making a big leap in knowledge about the interaction. The observed aging effects add well to the understanding of supramolecular consideration of SOM. By introducing nanothermal analysis to the field of soil science, it is made possible to face the problem of heterogeneity and spatial distribution of thermal characteristics. Another important achievement of AFM-nTA is that it can be used to detect physicochemical processes, which are of low intensity.
Die weltweite Zugänglichkeit und umfangreiche Nutzung des Internets machen dieses Medium zu einem effizienten und beliebten Informations-, Kommunikations-, und Verkaufsinstrument. Immer mehr Menschen und Organisationen versuchen, diese Vorzüge durch eine eigene Website für ihre Zwecke zu verwenden. Als hilfreiches Mittel zur Optimierung von Webpräsenzen bewährte sich in den letzten Jahren der Einsatz von Web-Analytics-Software. Durch diese Software sind Websitebetreiber in der Lage, Informationen über die Besucher ihrer Website und deren Nutzungsverhalten zu sammeln und zu messen. Das angestrebte Resultat sind Optimierungsentscheidungen auf Basis von Daten an Stelle von Annahmen und wirkungsvolle Testmöglichkeiten.
Für den Bereich des E-Commerce existieren bis dato zahlreiche wissenschaftliche und praxiserprobte Hilfestellungen für Web-Analytics-Projekte. Informationswebsites hingegen werden trotz ihrer Wichtigkeit nur vereinzelt thematisiert. Um diesem Defizit entgegenzuwirken, hat Hausmann 2012 das Framework for Web Analytics entwickelt, welches dem Anwender ein hilfreiches Referenzmodell für sein Web Analytics-Vorhaben bietet. Diesen Ansatz weiter voranzutreiben ist das Ziel der Abschlussarbeit. Dazu wird mithilfe einer Literaturanalyse und einer Fallstudie das Framework validiert und ergänzt, sowie weitere Handlungsempfehlungen identifiziert. Als Ergebnis werden die wichtigsten Erkenntnisse dieser Forschung zusammengefasst und für den zukünftigen Gebrauch festgehalten.
Large amounts of qualitative data make the utilization of computer-assisted methods for their analysis inevitable. In this thesis Text Mining as an interdisciplinary approach, as well as the methods established in the empirical social sciences for analyzing written utterances are introduced. On this basis a process of extracting concept networks from texts is outlined and the possibilities of utilitzing natural language processing methods within are highlighted. The core of this process is text processing, to whose execution software solutions supporting manual as well as automated work are necessary. The requirements to be met by these solutions, against the background of the initiating project GLODERS, which is devoted to investigating extortion racket systems as part of the global fiσnancial system, are presented, and their fulσlment by the two most preeminent candidates reviewed. The gap between theory and pratical application is closed by a prototypical application of the method to a data set of the research project utilizing the two given software solutions.
Im Rahmen des "Design Thinking"-Prozesses kommen unterschiedliche Varianten kreativitätsfördernder Techniken zum Einsatz. Aufgrund der zunehmenden Globalisierung ergeben sich immer häufiger Kollaborationen, bei denen sich die jeweiligen Projektteilnehmer an verteilten Standorten befinden. Somit erweist sich die Digitalisierung des Design-Prozesses als durchaus erstrebenswert. Ziel der hier vorliegenden Untersuchung ist daher die Erstellung eines Bewertungsschemas, welches die Eignung digitaler Kreativitätstechniken in Bezug auf das "Entrepreneurial Design Thinking" misst. Des Weiteren soll geprüft werden, inwiefern sich der Einsatz von e-Learning-Systemen in Kombination mit der Verwendung digitaler Kreativitätstechniken eignet. Diese Prüfung soll am Beispiel der e-Learning Software "WebCT" konkretisiert werden. Hieraus ergibt sich die folgende Fragestellung: Welche digitalen Kreativitätstechniken eignen sich für die Anwendung im Bereich des "Entrepreneurial Design Thinkings" unter Einsatz der e-Learning Plattform "WebCT"? Zunächst wird eine Literaturanalyse bezüglich des "Entrepreneurial Design Thinkings", der klassische und digitale Kreativitätstechniken sowie des Arbeitens in Gruppen, was auch das Content Management, e-Learning-Systeme und die Plattform "WebCT" beinhaltet, durchgeführt. Im Anschluss daran wird eine qualitative Untersuchung durchgeführt. Auf Basis bereits bestehender Literatur, soll ein Bewertungsschema erstellt werden, welches misst, welche der behandelten digitalen Kreativitätstechniken für den Einsatz im "Entrepreneurial Design Thinking" am besten geeignet ist. Darauf aufbauend erfolgt die Verknüpfung des digitalisierten "Design Thinking"-Prozesses mit der e-Learning Plattform "WebCT". Abschließend wird diskutiert, in wie fern diese Zusammenführung als sinnvoll erachtet werden kann.
Galerucinae, Latreille 1802 is the second largest subgroup of chrysomelidae. 1837 Chervrolat described the taxon Ootheca, which has originally only one listed species. Nearly 200 years all galerucinae with a "compact" bodyshape, a broad pronotum, a convex dorsum , short antennae and short legs were assigned to Ootheca. When I started a revision of Ootheca, this taxon included 38 species. Comparing morphological characters of the exoskeleton combined with the depiction/description of characteristic structures of the male genitalia allowed a detailed description of the genus Ootheca and its species. After the revision 9 valid species remained in Ootheca, 4 are described to be new, 13 species were transferred to other valid described genera and 10 species remained, because of a lack of unambiguous assignment. The examination of the median lobe additionally enables me to describe three sister taxa: Oothecoides (6 species), Ootibia (5 species ) und Oosagitta (6 species).
Pedestrian Detection in digital images is a task of huge importance for the development of automaticsystems and in improving the interaction of computer systems with their environment. The challenges such a system has to overcome are the high variance of the pedestrians to be recognized and the unstructured environment. For this thesis, a complete system for pedestrian detection was implemented according to a state of the art technique. A novel insight about precomputing the Color Self-Similarity accelerates the computations by a factor of four. The complete detection system is described and evaluated, and was published under an open source license.
This thesis deals with problems, which occure when rendering stereoscopic contents. These problems are elaborated, simulated with the help of a program developed in this thesis and evaluated by a group of volunteers. Thereby it shall be determined, whether the errors are noticeable and how much they influence the 3D effect of the stereoscopic images. Each error is simulated using different camera assemblies and evaluated depending on the choosen assembly.
Die vorliegende Arbeit wurde verfasst, um Einflüsse und Zusammenhänge von Mitarbeiterzufriedenheit auf Burnout zu erforschen. Zudem wurde der Frage nachgegangen, inwieweit organisationsbedingte Variablen beim Zusammenhang von Mitarbeiterzufriedenheit und Burnout bei Flugbegleitern eine Rolle spielen. Hierfür wurde die Airline-Branche, genau genommen das Kabinenpersonal als Repräsentant, verwendet und eine umfangreiche Arbeitsplatzanalyse durchgeführt.
Zur Erfassung der vielfältigen Dimensionen der Mitarbeiterzufriedenheit diente der Fragebogen zur Erfassung der Mitarbeiterzufriedenheit (FEMAZU), sowie für die Facetten von Burnout die Burnout-Screening-Skalen (BOSS) "Beruf" und "körperliche Beschwerden". Die organisationsbedingten Variablen wurden im Zuge einer Gruppendiskussion erhoben und zu entsprechenden Statements ausformuliert, um für den Fragebogen verwendet werden zu können. Dieser wurde im nach der Erstellung durch einen Pretest praktisch validiert. Die Online-Erhebung erfolgte anhand 420 Flugbegleitern im deutschsprachigen Raum.rnZu der quantitativen Erhebung wurde eine qualitative Methode angewandt, um detaillierter Informationen bezüglich der Komplexität in Entstehung und Verlauf der Krankheitsgeschichte von Burnout zu bekommen und Hinweise für die Einwirkung organisationsbedingter Variablen zu erhalten.
Entsprechend der repräsentativen Stichprobe in der vorliegenden Arbeit konnte ein starker Zusammenhang von Mitarbeiterzufriedenheit auf die verschiedenen Facetten von Burnout erwiesen sowie überwiegend signifikante Ergebnisse verzeichnet werden. Als wesentliche Einflussvariablen konnten individuelle Ziele, Arbeitsbedingungen, Aufgabenfeld, Empowerment, Commitment, Emotionsregulation und Work-Life-Balance identifiziert werden. Bedingt durch die ohnehin sehr speziellen Arbeitsbedingungen im Berufsleben der Flugbegleiter sollten die Airlines bei ihren Mitarbeitern auf eine ausgeglichene Work-Life-Balance achten. Die Ergebnisse zeigten hierfür deutliche Zusammenhänge mit Mitarbeiterzufriedenheit und Burnout. Um entsprechende ausfallsbedingten Kosten vorzubeugen, wurde in der vorliegenden Arbeit eine Handlungsempfehlung gegeben. Durch die hohe Flexibilitätsanforderung in der Tätigkeit des Kabinenpersonals sowie den zahlreichen physiologischen Einflüssen wie beispielsweise Lärm, Jetlag, Schichtdienst oder Zeitverschiebungen ist es für Unternehmen, die auf langfristige Mitarbeiter setzen besonders wichtig, an dieser Stelle häufigen und langen krankheitsbedingten Fehlzeiten vorzubeugen. Eine höhere Planstabilität, ein größerer Einfluss auf die Plangestaltung und ausreichend Ruhezeit würde beispielsweise der Vereinbarkeit von Beruf und Privat entgegen kommen.
Andere in der Literatur als bedeutend eruierten Variablen, wie bspw. die Arbeitsplatzsicherheit und der Zivilstand, zeigten keine oder nur eine sehr geringe Signifikanz. Abschließend wurden Faktoren, welche einen Einfluss auf das Ergebnis haben könnten, ausführlich erläutert und diskutiert sowie eine Empfehlung für die Praxis und zukünftige wissenschaftliche Untersuchungen abgeleitet. Insbesondere der Forschungsausblick zeigt, dass der Zusammenhang der Dimensionen Mitarbeiterzufriedenheit und Burnout, welche anhand der Stichprobe der Flugbegleiter in dieser Arbeit erhoben wurde, noch umfassende Erforschungen erfordert, um hier vor allem für die Wirtschaft Verbesserungen und entsprechende Kostenreduktion bewirken zu können. Sowohl für die Wirtschaft als auch die Wissenschaft wäre eine engere Zusammenarbeit wünschenswert und gewinnbringend.
Studies on the toxicity of chemical mixtures find that components at levels below no-observed-effect concentrations (NOECs) may cause toxicity resulting from the combined effects of mixed chemicals. However, chemical risk assessment frequently focuses on individual chemical substances, although most living organisms are substantially exposed to chemical mixtures rather than single substances. The concepts of additive toxicity, concentration addition (CA), and independent action (IA) models are often applied to predict the mixture toxicity of similarly and dissimilarly acting chemicals, respectively. However, living organisms and the environment may be exposed to both types of chemicals at the same time and location. In addition, experimental acquisition of toxicity data for every conceivable mixture is unfeasible since the number of chemical combinations is extremely large. Therefore, an integrated model to predict mixture toxicity on the basis of single mixture components having various modes of toxic action (MoAs) needs to be developed. The objectives of the present study were to analyze the challenges in predicting mixture toxicity in the environment, and to develop integrated models that overcome the limitations of the existing prediction models for estimating the toxicity of non-interactive mixtures through computational models. For these goals, four sub-topics were generated in this study. Firstly, applicable domains and limitations of existing integrated models were analyzed and grouped into three kinds of categories in this study. There are current approaches used to assess mixture toxicity; however, there is a need for a new research concept to overcome challenges associated with such approaches, which recent studies have addressed. These approaches are discussed with particular emphasis on those studies involved in computational approaches to predict the toxicity of chemical mixtures based on the toxicological data of individual chemicals. Secondly, through a case study and a computational simulation, it was found that the Key Critical Component (KCC) and Composite Reciprocal (CR) methods (as described in the European Union (EU) draft technical guidance notes for calculating the Predicted No Effect Concentration (PNEC) and Derived No Effect Level (DNEL) of mixtures) could derive significantly different results. As the third and fourth sub-topics of this study, the following two integrated addition models were developed and successfully applied to overcome the inherent limitations of the CA and IA models, which could be theoretically used for either similarly or dissimilarly acting chemicals: i) a Partial Least Squares-Based Integrated Addition Model (PLS-IAM), and, ii) a Quantitative Structure-Activity Relationship-Based Two-Stage Prediction (QSAR-TSP) model. In this study, it was shown that the PLS-IAM might be useful to estimate mixture toxicity when the toxicity data of similar mixtures having the same compositions were available. In the case of the QSAR-TSP model, it showed the potential to overcome the critical limitation of the conventional TSP model, which requires knowledge of the MoAs for all chemicals. Therefore, this study presented good potential for the advanced integrated models (e.g., PLS-IAM and QSAR-TSP), while considering various non-interactive constituents that have different MoAs in order to increase the reliance of conventional models and simplify the procedure for risk assessment of mixtures.
Im Rahmen dieser Masterarbeit wird ein umfassender Überblick über die Vielfalt der Sicherheitsmodelle gegeben, indem ausgewählte Sicherheitsmodelle beschrieben, klassifiziert und miteinander verglichen werden.
Sicherheitsmodelle beschreiben in einer abstrakten Weise die sicherheitsrelevanten
Komponenten und Zusammenhänge eines Systems. Mit den Sicherheitsmodellen können komplexe Sachverhalte veranschaulicht und analysiert werden.
Da Sicherheitsmodelle unterschiedliche Sicherheitsaspekte behandeln, beschäftigt
sich diese Arbeit mit der Ausarbeitung eines Klassifizierungsschemas, welches
die strukturelle und konzeptuelle Besonderheiten der Modelle in Bezug auf die zugrundeliegenden Sicherheitsaspekte beschreibt. Im Rahmen des Klassifizierungsschemas werden die drei grundlegenden Modellklassen gebildet: Zugriffskontrollmodelle, Informationsflussmodelle und Transaktionsmodelle.
Sicherheitsmodelle werden in einem direkten und indirekten Vergleich gegenüber gestellt. Im letzten Fall werden sie einer oder mehrerer Modellklassen des Klassifizierungsschemas zugeordnet. Diese Klassifizierung erlaubt, Aussagen über die betrachteten Sicherheitsaspekte und die strukturellen bzw. konzeptuellen Besonderheiten eines Sicherheitsmodells in Bezug auf die anderen Sicherheitsmodelle
zu machen.
Beim direkten Vergleich werden anhand der ausgewählten Kriterien die Eigenschaften
und Aspekte der Sicherheitsmodelle orthogonal zu den Modellklassen
betrachtet.
Iterative Signing of RDF(S) Graphs, Named Graphs, and OWL Graphs: Formalization and Application
(2013)
When publishing graph data on the web such as vocabulariesrnusing RDF(S) or OWL, one has only limited means to verify the authenticity and integrity of the graph data. Today's approaches require a high signature overhead and do not allow for an iterative signing of graph data. This paper presents a formally defined framework for signing arbitrary graph data provided in RDF(S), Named Graphs, or OWL. Our framework supports signing graph data at different levels of granularity: minimum self-contained graphs (MSG), sets of MSGs, and entire graphs. It supports for an iterative signing of graph data, e. g., when different parties provide different parts of a common graph, and allows for signing multiple graphs. Both can be done with a constant, low overhead for the signature graph, even when iteratively signing graph data.
Die Dissertation "Schreibprozesse in der Wikipedia" untersucht auf Basis einer linguistischen Textanalyse individuelle und gemeinschaftliche Schreibhandlungen in der Wikipedia. An Beispiel ausgewählter Artikel werden Artikelinitiationen, Handlungsmuster beim Er- und Überarbeiten der Texte, Prozesse des Planens, Gliederns und Bewertens sowie Kontroversen, Edit Wars und Vandalismus als grundlegende Aspekte des Schreibens in gemeinschaftlichen Online-Kontexten betrachtet. Dabei erscheinen vor allem Kontroversen als ein in der Schreibforschung bisher vernachlässigter Einflussfaktor, der nicht nur Auswirkungen auf die Schreibprozesse in der Wikipedia, sondern auch auf die gesamte Abbildung, Genese und vor allem Aushandlung von Wissen hat.
In a software reengineering task legacy systems are adapted computer-aided to new requirements. For this an efficient representation of all data and information is needed. TGraphs are a suitable representation because all vertices and edges are typed and may have attributes. Further more there exists a global sequence of all graph elements and for each vertex exists a sequence of all incidences. In this thesis the "Extractor Description Language" (EDL) was developed. It can be used to generate an extractor out of a syntax description, which is extended by semantic actions. The generated extractor can be used to create a TGraph representation of the input data. In contrast to classical parser generators EDL support ambiguous grammars, modularization, symbol table stacks and island grammars. These features simplify the creation of the syntax description. The collected requirements for EDL are used to determine an existing parser generator which is suitable to realize the requirements.
After that the syntax and semantics of EDL are described and implemented using the suitable parser generator. Following two extractors one for XML and one for Java are created with help of EDL. Finally the time they need to process some input data is measured.
The following thesis analyses the functionality and programming capabilitiesrnof compute shaders. For this purpose, chapter 2 gives an introductionrnto compute shaders by showing how they work and how they can be programmed. In addition, the interaction of compute shaders and OpenGL 4.3 is shown through two introductory examples. Chapter 3 describes an NBodyrnsimulation that has been implemented in order to show the computational power of compute shaders and the use of shared memory. Then it is shown in chapter 4 how compute shaders can be used for physical simulationsrnand where problems may arise. In chapter 5 a specially conceived and implemented algorithm for detecting lines in images is described and then compared with the Hough transform. Lastly, a final conclusion is drawn in chapter 6.
Die Arbeit stellt Path Tracing zum Rendern von Bildern mitrnglobaler Beleuchtung vor. Durch die Berechnung der Rendergleichung, mithilfe von Zufallsexperimenten, ist das Verfahren physikalisch plausibel. Entscheidend für die Qualität der Ergebnisse ist Sampling. Der Schwerpunktrnder Arbeit ist die Untersuchung verschiedener Samplingstrategien. Dazu werden die Ergebnisse unterschiedlicher Dichtefunktionen verglichenrnund die Methoden bewertet. Außerdem werden Effekte, wie beispielsweise Depth of Field, mittels Sampling visualisiert.
In dieser Arbeit wurde der Einfluss von nicht wässrigen Mahlflüssigkeiten auf Metall-Keramik-Pulvermischungen im Nassmahlprozess untersucht. Es wurden Al- und Cr-Al₂O₃-Pulvermischungen ausgewählt, um den Einfluss der Mahlflüssigkeiten auf die Mahlung von Metall-Keramik-Pulvermischungen mit einer duktilen (Aluminium) und einer spröden (Chrom) Metallkomponente zu untersuchen.
The amount of information on the Web is constantly increasing and also there is a wide variety of information available such as news, encyclopedia articles, statistics, survey data, stock information, events, bibliographies etc. The information is characterized by heterogeneity in aspects such as information type, modality, structure, granularity, quality and by its distributed nature. The two primary techniques by which users on the Web are looking for information are (1) using Web search engines and (2) browsing the links between information. The dominant mode of information presentation is mainly static in the form of text, images and graphics. Interactive visualizations offer a number of advantages for the presentation and exploration of heterogeneous information on the Web: (1) They provide different representations for different, very large and complex types of information and (2) large amounts of data can be explored interactively using their attributes and thus can support and expand the cognition process of the user. So far, interactive visualizations are still not an integral part in the search process of the Web. The technical standards and interaction paradigms to make interactive visualization usable by the mass are introduced only slowly through standardatization organizations. This work examines how interactive visualizations can be used for the linking and search process of heterogeneous information on the Web. Based on principles in the areas of information retrieval (IR), information visualization and information processing, a model is created, which extends the existing structural models of information visualization with two new processes: (1) linking of information in visualizations and (2) searching, browsing and filtering based on glyphs. The Vizgr toolkit implements the developed model in a web application. In four different application scenarios, aspects of the model will be instantiated and are evaluated in user tests or examined by examples.
In this thesis we discuss the increasingly important routing aggregation and its consequences on avoiding routing loops. As basis for implementation and evaluation I will use the RMTI protocol, developed at the University of Koblenz, which is an evolution of the RFC2453 specified in the Routing Information Protocol version 2. The virtual network environment Virtual Network User Mode Linux (VNUML) is used within this thesis as environment. With VNUML it is possible to operate and evaluate real network scenarios in a virtual environment. The RMTI has already proven its ability to detect topological loops and thereby prevent the formation of these routing loops. In this thesis we will describe the function of the RMTI and then discuss under which circumstances we can use routing aggregation, without it resulting in routing anomalies. In order to implement these changes it is essential to have a deeper understanding of the structure of routing tables, so the construction will be explained using reference to examples. There follows a description of which points have to be changed, in the RMTI in order to avoid loops despite aggregation. In Summary we will evaluate the affect the routing aggregation has on the reorganization ability of the virtual network.
This thesis deals with the development and evaluation of a concept of novel interaction with ubiquitous user interfaces. To accomplish the evaluation of this interaction concept, a prototype was implementated by using an existing head-mounted display solution and an android smartphone.
Furthermore, in the course of this thesis, a concrete use case for this prototype " the navigation through a city block with the aid of an electronic map " was developed and built as an executable application to help evaluate the quality of the interaction concept. Therefore, fundamental research results were achieved.