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In this cumulative thesis, I present four manuscripts and two appendixes. In the manuscripts I discuss mindsets and their relation to the effectiveness of negotiation training. My general claim is that mindsets promise to be relevant for training effectiveness. Still, more research needs to be done and my co-authors of chapter 3 and I present the Scale for the Integrative Mindset of Negotiators (SIM) that can be used for some of that research. In the appendixes, I present two negotiation training exercises. The first addresses an international refugee policy summit and the second a negotiation over the sale of a large solar pv park in Thailand.
The Authority, through its planners, implements its housing and urbanizing policy at the macro level by preparing the master plan and zoning processes. How far can the Authority intervene and limit the bundle of rights of the private ownership tenure? And how can externalities be minimized in the process of transformation from the traditional quarter to the new settlement? Political values, whether tacit or explicit, are manifested in the resultant designs. A theoretical base for new urban planning guidelines involving a comprehensive study of housing in Damascus with emphasis on social and cultural factors is the ultimate aim of this research. The research starts with a historical review of the Muslim City in general and distinguishes between cities that existed before Islam and then were conquered and modified by Muslims and cities established by Muslim Authority. The focus is only on the residential quarters in the city and the local market, mosque and etc (outside the old walled city of Damascus). Other Muslim city´ urban elements such as Grand mosque, caliph´s residency, Citadel and etc. are not in the scope of this study. A brief historical review of Damascus before and during Islam and the development of residential quarters are illustrated. Later, the study analyzes the traditional residential quarter and explores the building guidelines that governed the evolution of the built form of the quarter. (Literature reviews based mainly on researches conducted by others). Then, the study explores the multi-faceted changes (economic, social and political) that the Middle Eastern region went through, in the last century, in general and the effect of those changes on the city form, case of Damascus. The effect will be traced through examining the decrees that the Authority issued in order to govern land reform and manage public and private domains. Then, the study looks at the ramifications of those decrees on the urban form of Damascus. It also investigates the decrees that were the guide for new planning and organizing developments. The study will inspect the end products of the planning and organizing process by studying several cases of building permits. Then, provides morphology of the new residential sub-quarter and its urban form. Based on lessons learned from the previous decades of housing policy, the study will recommend foundation for governmental norms to produce responsive physical and social urban forms.
The emission of anthropogenic trace substances into the aquatic environment continuously poses challenges to water suppliers. The contamination of raw waters with organic trace substances requires complex water treatment processes to secure drinking water quality. The routine monitoring of these raw waters as well as the behavior and fate of organic trace substances during different treatment processes is of great interest to recognize and counter potential dangers at an early stage. Chromatographic separation techniques coupled to triple quadrupole mass spectrometers are conventionally used for the reliable monitoring of traces of known polar substances. However, such analytical techniques usually fail to recognize unknown compounds. This weakness presents a serious restriction with regard to the monitoring of treatment processes, since transformation products are often not - or not sufficiently - characterized and are thus only detected sporadically. Non-target screening using liquid chromatography coupled to high-resolution mass spectrometry (LC-HRMS) allows the detection of thousands of compounds within a single run and covers known as well as unknown substances. Compared to the established analytical techniques, this is a decisive advantage for the monitoring of raw and process waters during water treatment. While the analytical technique LC-HRMS has undergone significant developments in recent years, the algorithms for data processing reveal clear weaknesses. This dissertation therefore deals with reliable processing strategies for LC-HRMS data. The first part of this work seeks to highlight the problematics of false positive and false negative findings. Based on repeated measurements, various strategies of data processing were assessed with regard to the repeatability of the results. To ensure that real peaks were barely or not removed by the filtering procedure, samples were spiked with isotope-labeled standards. The results emphasize that the processing of sample triplicates results in sufficient repeatability and that the signal fluctuation across the triplicates emerged as a powerful filtering criteria. The number of false positives and false negatives could be significantly reduced by the developed strategies which consequently improve the validity of the data. The second part of this thesis addresses the development of processing strategies particularly aimed at assessing water treatment processes. The detected signals were tracked across the treatment process and classified based on their fold changes. A more reliable signal classification was achieved by implementing a recursive integration approach. Special integration algorithms allow a reliable signal classification even though the signal to be compared was below the intensity threshold. Different combinations of replicates of process influents and effluents were processed for evaluating the repeatability. The good repeatability was indicated by the results of both the plausibility checks and the ozonation process (ozonation of pretreated river water) and thus points to high reliability. The developed procedure enables the assessment of water treatment processes based on the changes in the pattern of all detected signals and offers a more comprehensive picture of the treatment efficiency. Particularly with regard to transformation products, existing knowledge gaps can be reduced by this approach, albeit the entire variety of chemicals cannot be covered completely. The applicability of the developed strategies to real world applications is demonstrated in the last part of this work. Besides the prioritization of the generated results, the main focus was the identification of recognized compounds. The developed strategies clearly improve the validity of the underlying data. The combination of LC-HRMS analysis with reliable processing strategies opens up multiple possibilities for a more comprehensive monitoring of water resources and for the assessment of water treatment processes. The processing strategies and validation concepts may be easily transferred to other research fields.
Online marketing, especially Paid Search Advertising, has become one of the most important paid media channels for companies to sell their products and services online. Despite being under intensive examination by a number of researchers for several years, this topic still offers interesting opportunities to contribute to the com- munity, particularly because of its large economic impact and practical relevance as well as the detailed and widely unfiltered view of consumer behavior that such marketing offers. To provide answers to some of the important questions from advertisers in this con- text, I present four papers in my thesis, in which I extend previous works on optimization topics such as click and conversion prediction. I apply and extend methods from other fields of research to specific problems in Paid Search. After a short introduction, I start with a paper in which we illustrate a new method that helps advertisers to predict conversion probabilities in Paid Search using sparse keyword- level data. We address one of the central problems in Paid search advertising, which is optimizing own investments in this channel by placing bids in keyword auctions. In many cases, evaluations and decisions are made with extremely sparse data, al- though anecdotal evidence suggests that online marketing is a typical
Netzwerkbildung im Musiksektor Niedersachsen : Funktionsweisen und Mechanismen sozialer Formationen
(2018)
In Niedersachsen existiert eine florierende, ausdifferenzierte kulturelle Szene. Vor allem im Musikbereich sind zahlreiche, teilweise international agierende Initiativen und einige kleinere und mittlere Unternehmen wie auch Solokünstler aktiv, die in einem regen Austausch miteinander stehen. Diese Akteure treten in der Regel mit der Erwartung einer positiven Auswirkung und Nutzensteigerung einem Netzwerk bei. Selten wird jedoch hinterfragt oder im Anschluss evaluiert, inwiefern das jeweilige Netzwerk zur positiven Verstärkung der Einzelakteure, im ökonomischen wie auch im sozialen oder kulturellen Sinne geführt hat, beziehungsweise inwieweit Netzwerkbildungen auch zu negativen Effekten für ihre Akteure führen können. In dieser Dissertation wird mit qualitativen Methoden und auf theoretischer Basis der Relationalen Soziologie die Situation in Bezug auf Netzwerkbildungen im Musiksektor von Niedersachsen analysiert. Dies geschieht vor den Fragen, wer die Akteure in Niedersachsen sind, und welchen Funktionsweisen und Mechanismen ihre Vernetzungsbestrebungen unterliegen. Ferner werden die Interaktionen zwischen sozialen Akteuren und institutioneller Kulturarbeit im Musiksektor dargestellt und aufgezeigt, welche Prozesse in diesem Musiknetzwerk unter dem Einfluss institutioneller Strukturen ablaufen.
Social insects like honeybees (Apis mellifera) and stingless bees (Apidae: Meliponini) face a relatively high risk to be attacked by pests and pathogens. To decrease the risk of infection, in addition to an innate immune system, these species have evolved various cooperative defense mechanisms such as hygienic behavior or allo-grooming, which contribute to the overall health of the colonies and are therefore also referred to as social immunity. The collection and use of plant resin is another important strategy of social immunity. Resin is a sticky, often aromatic substance with antimicrobial and deterrent properties secreted by plants for protection of the vegetative tissue. Honeybees and stingless bees take advantage of these properties by using resins for nest construction (often mixtures of resin and wax called “propolis” or “cerumen”) and as defense against pests and pathogens. Plant resins, thus, play a crucial role for the ecology of these species and are an important resource for them. Nevertheless, how bees exploit available resin sources and if resin collection can protect colonies from diseases received comparatively little attention in the past. Therefore the aim of this thesis is to provide new insights into the plant origin and significance as well as the influence of resin resource diversity on bee colony health. Resource use and availability form fundamental prerequisites, having decisive influence on the viability of individuals and maintenance of populations. Information on the resources required by a species is thus important to effectively promote and preserve it. For honeybees (A. mellifera) in temperate regions, precise information about which resin sources they use is largely lacking. By chemical comparing bee-collected resins and tree resins, I traced back the resin sources used by individual bees. Results show that honeybees collect distinct resin types that are related to different tree species (several poplar species: Populus balsamifera, P. xcanadensis; Betula alba; Aesculus hippocastanum; several poplar species). With this study I provided the first evidence, that A. mellifera in temperate regions use a variety of different tree species as resin sources and, moreover, show preferences for specific resin sources. Maintenance of colony health is probably one of the major purposes of resin collection. Nevertheless, studies investigating the benefits of resins at the colony level are rare and there are only few evidences on the effects of raw propolis (unlike commonly used ethanol extracts) on colony health. For this reason, I conducted an experimental field study in which I investigated whether propolis, as it is naturally deposited in the nests, can protect honeybee colonies against some of the most important pathogens (Varroa destructor mite, Deformed Wing Virus). The results of this study showed that propolis in (semi-) natural conditions can increase the disease resistance of honeybee colonies, underscoring the importance of resins for honeybee health. Resin collection by stingless bees is comparatively well studied and it is known that these species commonly forage on a variety of different plant species. To increase knowledge on whether and how bees may profit from a diversity of resin resources, I tested how the protective function of a resin varied among different sources (and their mixtures) and various potential aggressors (predators, parasites and pathogens). The results of this study revealed that resins from different trees vary in their effectivity against different target organisms. Moreover, resin blends were more effective than some of the individual resins, suggesting that bees can benefit from a variety of resin resources. In summary, honeybees in temperate regions, similar to tropical stingless bees, use a variety of different tree species as resin sources. Because resins from different tree species varied in their protective function, this indicates that bees can profit from a variety of different resins/resin sources by improving the defense against diverse pests and pathogens. Conversely, the lack of resin had a negative impact on the disease resistance of colonies. Consequently, availability as well as the variety of suitable resin sources is of great importance for the health of bees. In addition to nectar and pollen, resin, as a further important resource, should therefore find more attention in beekeeping. Resin collection as the natural disease defense of bees should find more respect in beekeeping praxis and should be more strongly included in future consideration on how to promote bee colony health.
The overall aim of this PhD-thesis is to develop empirical probabilistic frameworks that help to quantify the impacts of temporal and spatial scale dependencies and model uncertainties of climate projections regarding precipitation-dependent parameters. The thesis is structured in four journal articles. Article one is the first study that analyzed climate projections from the spatially highly resolved regional climate model (RCM) ensemble EURO-CORDEX. Additionally, the significance and the robustness of the projected changes are analyzed, and improvements related to the higher horizontal resolution of the new data set are discussed. A major finding is, that RCM simulations provide higher daily precipitation intensities, which are missing in the global climate model (GCM) simulations, and that they show a significantly different climate change of daily precipitation intensities with a smoother shift from low towards high intensities. The second article elaborates on impacts of temporal and spatial aggregation on extreme precipitation intensities. By combining radar data with cloud observations, the different temporal and spatial scaling behavior of stratiform and convective type precipitation events can be analyzed for the first time. The separation between convective and stratiform type events also allows to quantify the contribution of convective events to the extremes. Further, it is shown that temporal averaging has similar effects on the precipitation distribution as spatial averaging. Associated pairs of temporal and spatial resolutions that show comparable intensity distributions are identified. Using precipitation data from radar observations, a gauge station network and a spatially highly resolved regional climate model, the third paper optimizes the process that finds associated temporal and spatial scales (see second article). This information is used to develop a method that adjusts point measurements to the temporal and spatial scale of a previously defined model grid. The study shows that this procedure can be used to improve bias-adjustment methods in areas with a low gauge station density. It is known that the EURO-CORDEX ensemble overestimates precipitation and shows a common cold bias in the Alpine region. The fourth article evaluates how these biases are changing the temperature distribution and the temperature dependency of precipitation-frequencies. These biases are a source of uncertainty that is not captured by the robustness tests performed in the first article. A probabilistic-decomposition-framework is developed to quantify the impact of these biases on precipitation-frequency changes and to investigate causes for the ensemble spread.
The process perspective provides a unifying framework that has substantially contributed to our understanding of entrepreneurship. However, much of the research up to now has neglected this process oriented conception of entrepreneurship. There is therefore a need for studies that take the inherent dynamic processes into account and analyze the underlying mechanisms when researching entrepreneurship. This dissertation aims to improve our understanding of the entrepreneurial process. Specifically, this dissertation focuses on new venture creation and the processes of sustainable opportunity identification and opportunity deviation. Chapter 1 provides a general introduction that highlights the theoretical contributions of this dissertation and gives an overview over the conducted studies. Chapter 2 argues for a process model of entrepreneurship that places entrepreneurs and their actions center stage. The model combines different perspectives and levels of analysis and provides an integrative framework for researching new venture creation. In chapter 3 we establish and test a theoretical model of sustainable opportunity identification. The chapter explains how younger generations identify sustainable opportunities. The findings indicate that sustainable opportunity identification is a process with two transitions from problem to solution identification and from solution identification to sustainable opportunity identification. These transitions are contingent on awareness of consequences and entrepreneurial attitude. Chapter 4 offers insights into how deviation from the original opportunity increases the performance of entrepreneurial teams. The findings indicate that entrepreneurial teams with a high level of error orientation set themselves higher goals when deviating from their original opportunity. Higher goals then lead to higher team performance. Chapter 5 summarizes the overall findings and outlines the general theoretical and practical implications. Each chapter thus contributes to the process perspective by focusing on how different phases of the entrepreneurial process unfold and develop over time. Thereby, this dissertation advances our understanding of entrepreneurship as a process.
Seit den frühen 1990er Jahren wird transdisziplinäre Nachhaltigkeitsforschung in Form von problemorientierten Forschungs- und Lernprojekten konzeptioniert und praktisch umgesetzt, an denen außeruniversitäre Akteur_innen beteiligt sind. Diese Forschungsarbeit verfolgt drei Ziele: Erstens, die Konzeptualisierung der Begriffe Kultur, Multi-, Inter- und Transkulturalität in der Literatur zur transdisziplinären Nachhaltigkeitsforschung zu untersuchen. Zweitens, die Konzeptionierung und Umsetzung von transdisziplinären Forschungs- und Lernprojekten in Hinblick auf kulturelles Differenzieren zu analysieren. Drittens, konzeptionelle Beiträge zur Gestaltung von transdisziplinären Forschungs- und Lernprojekten zu entwickeln. Methodisch wird auf Literaturanalysen und eine qualitative Untersuchung zweier transdisziplinärer Lernforschungsprojekte zurückgegriffen. Unter dem Begriff Forschungs- und Lernprojekt werden in dieser Forschungsarbeit sowohl Forschungsprojekte als auch Lehr-Lernforschungsprojekte gefasst. Zentrale Ergebnisse der Forschungsarbeit sind die Folgenden: Erstens wird der Kulturbegriff in der transdisziplinären Nachhaltigkeitsforschung zwar vielfältig verwendet, als Forschungsthema, Hintergrund von Beteiligten, Kooperationsweise, Projektkontext, in Hinblick auf Interkulturalität oder als Wissenskultur, allerdings kaum ausdifferenziert und konkretisiert. Zweitens besteht auf der Ebene der Konzeptionierung von transdisziplinären Forschungs- und Lernprojekten: 1) ein starkes Übergewicht von Integration und Konsens gegenüber einer Auseinandersetzung mit Differenz, 2) eine implizite Vorauswahl von Beteiligten durch bestimmte Begrifflichkeiten und methodologische Ansätze und 3) eine Reproduktion von Machtverhältnissen durch (dichotome) Symmetrie- und Ausgleichsvorstellungen. Drittens zeigt sich auf der Ebene der Umsetzung von Lernforschungsprojekten: 1) eine starke Prozessorientierung der Projekte, 2) ein Spannungsfeld zwischen einer Öffnung und Steuerung in Hinblick auf den Projektverlauf und 3) vielfältige Differenzaushandlungen in Interaktionen (wie Zeitlichkeit, Verantwortung, Erfahrung, Relevanz). Die Ergebnisse zeigen, dass politische Implikationen der Forschung und zentrale Ungleichheitskategorien der Kultur- und Sozialwissenschaften (u.a. race, class, gender, body) kaum thematisiert werden. Vorschläge zur Gestaltung transdisziplinärer Forschungs- und Lernprojekte werden in Hinblick auf ein Verständnis von Forschungsdesigns als Prozesse, einem Erkunden von Differenzierungen und Forscher_innen-Positionen und der Bedeutung eines Verlernens entwickelt. Die folgenden Vorschläge zur Gestaltung von transdisziplinären Forschungs- und Lernprojekten werden aus den Ergebnissen entwickelt: Kulturkonzepte sollten nicht als voneinander getrennt, sondern als miteinander verschränkt betrachtet werden. Generell sollten Kulturkonzepte stärker definiert werden. So können durch offene Kulturkonzepte problematische Implikationen (Stereotypen, Rassismus, Kulturalisierung) vorgebeugt werden, die Zielen transdisziplinärer Forschung entgegenstehen. In Hinblick auf die Arten und Weisen kulturellen Differenzierens sollte bewusster mit Differenzierungen umgegangen werden (Wer differenziert wen wie?). Dies schließt ein, eine Sensibilität gegenüber kulturellem Differenzieren zu entwickeln und Differenzierungen in Forschungsprozessen zu erkunden. Kulturelles Differenzieren entfaltet ein wichtiges epistemologisches und transformatives Potential in der transdisziplinären Forschung, um Selbstverständlichkeiten zu reflektieren und Gemeinsamkeiten zu entdecken.