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Business rules have become an important tool to warrant compliance at their business processes. But the collection of these business rules can have various conflicting elements. This can lead to a violation of the compliance to be achieved. This conflicting elements are therefore a kind of inconsistencies, or quasi incon- sistencies in the business rule base. The target for this thesis is to investigate how those quasi inconsistencies in business rules can be detected and analyzed. To this aim, we develop a comprehensive library which allows to apply results from the scientific field of inconsistency measurement to business rule formalisms that are actually used in practice.
The mitral valve is one of four human heart valves. It is located in the left heart and acts as a unidirectional passageway for blood between the left atrium and the left ventricle. A correctly functioning mitral valve prevents a backflow of blood into the pulmonary circulation (lungs) and thus constitutes a vital part of the cardiac cycle. Pathologies of the mitral valve can manifest in a variety of symptoms with severity ranging from chest pain and fatigue to pulmonary edema (fluid accumulation in the tissue and air space of lungs), which may ultimately cause respiratory failure.
Malfunctioning mitral valves can be restored through complex surgical interventions, which greatly benefit from intensive planning and pre-operative analysis. Visualization techniques provide a possibility to enhance such preparation processes and can also facilitate post-operative evaluation. The work at hand extends current research in this field, building upon patient-specific mitral valve segmentations developed at the German Cancer Research Center, which result in triangulated 3D models of the valve surface. The core of this work will be the construction of a 2D-view of these models through global parameterization, a method that can be used to establish a bijective mapping between a planar parameter domain and a surface embedded in higher dimensions.
A flat representation of the mitral valve provides physicians with a view of the whole surface at once, similar to a map. This allows assessment of the valve's area and shape without the need for different viewing angles. Parts of the valve that are occluded by geometry in 3D become visible in 2D.
An additional contribution of this work will be the exploration of different visualizations of the 3D and 2D mitral valve representations. Features of the valve can be highlighted by associating them with specified colors, which can for instance directly convey pathology indicators.
Quality and effectiveness of the proposed methods were evaluated through a survey conducted at the Heidelberg University Hospital.
The Internet of Things is still one of the most relevant topics in the field of economics and research powered by the increasing demand of innovative services. Cost reductions in manufacturing of IoT hardware and the development of completely new communication ways has led to the point of bil-lions of devices connected to the internet. But in order to rule this new IoT landscape a standardized solution to conquer these challenges must be developed, the IoT Architecture.
This thesis examines the structure, purpose and requirements of IoT Architecture Models in the global IoT landscape and proposes an overview across the selected ones. For that purpose, a struc-tured literature analysis on this topic is conducted within this thesis, including an analysis on three existing research approaches trying to frame this topic and a tool supported evaluation of IoT Archi-tecture literature with over 200 accessed documents.
Furthermore, a coding of literature with the help of the specialised coding tool ATLAS.ti 8 is conduct-ed on 30 different IoT Architecture Models. In a final step these Architecture Models are categorized and compared to each other showing that the environment of IoT and its Architectures gets even more complex the further the research goes.
Absicherung der analytischen Interpretation von Geolokalisierungsdaten in der Mobilfunkforensik
(2019)
Abstract
Location based services maybe are within one of the most outstanding features of modern mobile devices. Despite the fact, that cached geolocation data could be used to reconstruct motion profiles, the amount of devices capable to provide these information in the field of criminal investigations is growing.
Motivation
The aim of this work is to generate in-depth knowledge to questions concerning geolocation in the field of mobile forensics, making especially somehow cached geolocation data forensically valuable. On top, tools meeting the specific requirements of law enforcement personnel shall be developed.
Problems
Geolocation processes within smartphones are quite complex. For the device to locate its position, different reference systems like GPS, cell towers or WiFi hot\-spots are used in a variety of ways. The whole mobile geolocation mechanism is proprietary to the device manufacturer and not build with forensic needs in mind. One major problem regarding forensic investigations is, that mainly reference points are being extracted and processed instead of real life device location data. In addition, these geolocation information only consist of bits and bytes or numeric values that have to be securely assigned to their intended meaning. The location data recovered are full of gaps providing only a part of the process or device usage. This possible loss of data has to be determined deriving a reliable measurement for the completeness, integrity and accuracy of data. Last but not least, as for every evidence within a criminal investigation, it has to be assured, that manipulations of the data or errors in position estimation have no disadvantageous effect on the analysis.
Research Questions
In the context of localisation services in modern smartphones, it always comes back to similar questions during forensic everyday life:
* Can locations be determined at any time?
* How accurate is the location of a smartphone?
* Can location data from smartphones endure in court?
Approach
For a better understanding of geolocation processes in modern smartphones and to evaluate the quality and reliability of the geolocation artefacts, information from different platforms shall be theoretically analysed as well as observed in-place during the geolocation process. The connection between data points and localisation context will be examined in predefined live experiments as well as desktop- and native applications on smartphones.
Results
Within the scope of this thesis self developed tools have been used for forensic investigations as well as analytical interpretation of geodata from modern smartphones. Hereby a generic model for assessing the quality of location data has emerged, which can be generally applied to geodata from mobile devices.
Despite the inception of new technologies at a breakneck pace, many analytics projects fail mainly due to the use of incompatible development methodologies. As big data analytics projects are different from software development projects, the methodologies used in software development projects could not be applied in the same fashion to analytics projects. The traditional agile project management approaches to the projects do not consider the complexities involved in the analytics. In this thesis, the challenges involved in generalizing the application of agile methodologies will be evaluated, and some suitable agile frameworks which are more compatible with the analytics project will be explored and recommended. The standard practices and approaches which are currently applied in the industry for analytics projects will be discussed concerning enablers and success factors for agile adaption. In the end, after the comprehensive discussion and analysis of the problem and complexities, a framework will be recommended that copes best with the discussed challenges and complexities and is generally well suited for the most data-intensive analytics projects.
The loss of biodiversity is recognised on a global scale and also in the anthropogenic landscapes used for agriculture, now covering almost 50% of the global terrestrial land surface. In agriculture pesticides, biologically active chemicals are deliberately distributed to control pests, disease and weeds in the cropped areas. The quantification of remaining semi-naturals structures such as field margins and hedges is a prerequisite to understand the impact of pesticides on biodiversity, since these structures represent habitats for many organisms in agricultural landscapes. The presence of organisms in these habitats and crops is required to obtain an estimate of their potential pesticide exposure. In this text I provide studies on animal groups so far not addressed in risk assessment procedures for the regulation of pesticides such as amphibians, moths and bats. For all groups it becomes apparent that they are present in agricultural landscapes and potentially coincide with pesticide applications indicating a risk. Risk quantification also requires data on the sensitivity of organisms and here data for plants, amphibians and bees are presented. Effects translating to community level were studied for herbicide, insecticide and fertiliser effects in a natural system. After three years the treatments resulted in simplified plant communities with lower species numbers and a reduction in flowering plants. This reduction of flowers is used as an example for an indirect effect and was especially obvious for the effect of an herbicide on the common buttercup. Sublethal herbicide effects for a plant translated in an impact on feeding caterpillars, indicating a reduction in food quality. Insecticide inputs realistic for field margins also reduced moth pollination of white champion flowers by 30%. These indirect effects by distortions of food web characteristics are playing a critical role to understand declines in organism groups, however so far are not accounted for in pesticide risk assessment schemes. The current intense use of pesticides in agriculture and their inherent toxicity may lead to a chemical landscape fragmentation, where populations may not be connected anymore. Source-sink dynamics are important ecological processes and as a final result not only population size but also genetic population structure might be affected. Including potential pesticide impacts as costs in a model for amphibians migrating to breeding ponds in vineyards in Rhineland-Palatinate indicated the isolation of investigated populations. A first validation by analyzing the population structure of the European common frog confirmed the model prediction for some sites. For the regulation of pesticides in Europe a risk assessment is required and for the organisms of the terrestrial habitat a multitude of guidance documents is in place or is recently developed or improved. The results of the presented research indicate that wild plants and especially their reproductive flower stage are highly sensitive and risks are underestimated. Population recovery of arthropods needs a reevaluation at landscape scale and the addition of amphibian risk assessment in regulation procedures is suggested. However, developing or adopting risk assessment procedures and test systems is a time consuming task and therefore the establishment of risk management options is a pragmatic alternative with immediate effects. Artificial wetlands in the agricultural landscape proved to be important foraging sites for bats and their creation could mitigate negative pesticide effects. The integration of direct and indirect effects in a risk assessment scheme for all organism groups addressing also landscape scale and pesticide mixtures requires a long developing time. The establishment of model landscapes where management options and integrated pest management are applied on a larger scale would allow us to study pesticide effects in a realistic scenario and to develop an approach for the agriculture of the future.
The erosion of the closed innovation paradigm in conjunction with increasing competitive pressure has boosted the interest of both researchers and organizations in open innovation. Despite such rising interest, several companies remain reluctant to open their organizational boundaries to practice open innovation. Among the many reasons for such reservation are the pertinent complexity of transitioning toward open innovation and a lack of understanding of the procedures required for such endeavors. Hence, this thesis sets out to investigate how organizations can open their boundaries to successfully transition from closed to open innovation by analyzing the current literature on open innovation. In doing so, the transitional procedures are structured and classified into a model comprising three phases, namely unfreezing, moving, and institutionalizing of changes. Procedures of the unfreezing phase lay the foundation for a successful transition to open innovation, while procedures of the moving phase depict how the change occurs. Finally, procedures of the institutionalizing phase contribute to the sustainability of the transition by employing governance mechanisms and performance measures. Additionally, the individual procedures are characterized along with their corresponding barriers and critical success factors. As a result of this structured depiction of the transition process, a guideline is derived. This guideline includes the commonly employed actions of successful practitioners of open innovation, which may serve as a baseline for interested parties of the paradigm. With the derivation of the guideline and concise depiction of the individual transitional phases, this thesis consequently reduces the overall complexity and increases the comprehensibility of the transition and its implications for organizations.
Die Nachhaltigkeitsberichterstattung kann als ein zentrales Element einer konsequenten Unternehmensstrategie zur Umsetzung der gesellschaftlichen Verantwortung (Corporate Social Responsibility) angesehen werden. Um die Unternehmen bei dieser Aufgabe zu unterstützen stellt die Global Reporting Initiative (GRI) mit ihren G4 Leitlinien einen Orientierungsrahmen bereit, dessen Anwendung sich allerdings für Klein und Mittelunternehmen sehr komplex gestaltet. Ein branchenspezifisches Sector Supplement für den Weinbau existiert derzeit noch nicht.
Ziel der vorliegenden Arbeit ist es, diese Forschungslücke durch die Entwicklung weinbauspezifischer Nachhaltigkeitsaspekte und Indikatoren zu schließen, um den Betrieben eine selbstständige GRI-konforme Berichterstattung zu ermöglichen.
Der Prozess zur Identifikation wesentlicher Nachhaltigkeitsaspekte und -indikatoren erfolgt mittels Erhebungs- und Auswertungsmethoden der qualitativen Sozialforschung in Form
von Workshops, betrieblichen Vorortanalysen und Experteninterviews.
Parallel dazu erfolgt eine umfassende Analyse der weinbaulichen Wertschöpfungskette in Form einer Internet- und Literaturrecherche. Diese umfasst vorrangig die ökologischen Nachhaltigkeitsaspekte als diejenigen Bestandteile weinbaulicher Tätigkeiten, die sich sowohl positiv als auch negativ auf die Umwelt auswirken können. Anschließend erfolgt die zentrale Priorisierung der identifizieren Handlungsfelder und Nachhaltigkeitsthemen durch die Stakeholder. Zur Visualisierung der bewerteten Handlungsfelder dient das Instrument der Wesentlichkeitsanalyse.
Auf dieser Basis erfolgt die Entwicklung eines Handlungsleitfadens zur Erstellung von Nachhaltigkeitsberichten in der Weinwirtschaft. Hiermit erlangen Weingüter die praktische Kompetenz ein eigenes Nachhaltigkeitsreporting anzugehen.
Im Rahmen der Arbeit wurde auch ein elektronisches Tool entwickelt, das den Betrieben die Möglichkeit eröffnet, betriebliche Umweltaspekte zu erfassen und zu bewerten. Gleichzeitig wird den Anwendern damit die Generierung eines überbetrieblichen Vergleichs der Umweltleistung ermöglicht (Benchmarking).
Eine weitere Forschungsfrage der vorliegenden Arbeit beschäftigt sich mit der Biodiversitätserfassung und -bewertung für Rebland. Hintergrund sind die bisher nur geringen Funde auf der durch das Bundesamt für Naturschutz festgelegten Kennartenlisten bzw. den HNV-Stichprobenflächen (High nature value farmland-Indikator) für Rebland.
Hierzu wurde mittels Geoinformationssystemen das Artenvorkommen in rheinland-pfälzischen Weinanbaugebieten analysiert und 30 Pflanzenarten als Indikatorarten für den Weinbau abgeleitet. Ergänzend wurden weinbergstypische, geschützte Tierarten als „Bonusarten“ identifiziert. Die Indikatorarten werden den Winzern als ein Instrument zur eigenständigen Erfassung der Biodiversität in den Weinbergen dienen und im Rahmen einer Nachhaltigkeitsberichterstattung herangezogen werden können.
Streams are coupled with their riparian area. Emerging insects from streams can be an important prey in the riparian area. Such aquatic subsidies can cause predators to switch prey or increase predator abundances. This can impact the whole terrestrial food web. Stressors associated with agricultural land use can alter insect communities in water and on land, resulting in complex response patterns of terrestrial predators that rely on prey from both systems.
This thesis comprises studies on the impact of aquatic nsects on a terrestrial model ecosystem (Objective 1, hapter 2), the influence of agricultural land use on riparian spiders’ traits and community (Objective 2, Chapter 3), and on the impact of agricultural land use on the contribution of different prey to spider diet (Objective 3, Chapter 4).
In chapter 2, I present a study where we conducted a mesocosm experiment to examine the effects of aquatic subsidies on a simplified terrestrial food web consisting of two types of herbivores (leafhoppers and weevils), plants and predators (spiders). I focused on the prey choice of the spiders by excluding predator immigration and reproduction. In accordance with predator switching, survival of leafhoppers increased in the presence of aquatic subsidies. By contrast, the presence of aquatic subsidies indirectly reduced weevils and herbivory.
In chapter 3, I present the results on the taxonomic and trait response of riparian spider communities to gradients of agricultural stressors and environmental variables, with a particular emphasis on pesticides. To capture spiders with different traits and survival strategies, we used multiple collection methods. Spider community composition was best explained by in-stream pesticide toxicity and shading of the stream bank, a proxy for the quality of the habitat. Species richness and the number of spider individuals, as well as community ballooning ability, were negatively associated with in-stream pesticide toxicity. In contrast, mean body size and shading preference of spider communities responded strongest to shading,
whereas mean niche width (habitat preference for moisture and shading) responded strongest to other environmental variables.
In chapter 4, I describe aquatic-terrestrial predator-prey relations with gradients of agricultural stressors and environmental variables. I sampled spiders, as well as their aquatic and terrestrial prey along streams with an assumed pesticide pollution gradient and determined their stable carbon and nitrogen signals. Potential aquatic prey biomass correlated positively with an increasing aquatic prey contribution of T. montana. The contribution of aquatic prey to the diet of P. amentata showed a positive relationship with increasing toxicity in streams.
Overall, this thesis contributes to the emerging discipline of cross-ecosystem ecology and shows that aquatic-terrestrial linkages and riparian food webs can be influenced by land use related stressors. Future manipulative field studies on aquatic-terrestrial linkages are required that consider the quality of prey organisms, fostering mechanistic understanding of such crossecosystem effects. Knowledge on these linkages is important to improve understanding of consequences of anthropogenic stressors and to prevent further losses of ecosystems and their biodiversity.