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Im Mittelpunkt der Systemprogrammierung steht die Entwicklung, Anpassung, parametergesteuerte Generierung und Betreuung der gesamten Betriebssoftware eines DV-Systems sowie eine Unterstützung bei der Anpassung von Basissoftware und Anwendungssoftware an ein Betriebssystem. Der vorliegende Text beinhaltet folgende Themen: Beschreibung grundlegender Aspekte von Rechnerarchitektur, Sprachkonzepte höherer Programmiersprachen, systemnahe Aspekte der Programmierung, Konzepte der objektorientierten Programmierung etc.
During the nineties of the last century, several formerly monopolistic markets (telecommunication, electricity, gas, and railway) have been deregulated in Germany based on European directives and theoretically inspired by the theory of contestable markets. The original contestable market theory implied three assumptions necessary to be satisfied to establish potential competition: Free market entry, market exit possible without any costs, and the price adjustment lag exceeding the entry is shows that if the incumbent reduces its prices slowly (high adjustment lag) and the market entry can be performed quickly (low entry lag), a new competitor will be able to earn back sunk costs. Therefore it is not necessary that all three conditions are complied with for potential competition to exist. Applying this 'revised' contestable market theory to the deregulated sectors in Germany sections, natural monopolies can be identified in telecommunication local loops and local/regional connection networks, in the national electricity grid and the regional/local electricity distribution networks, in the national and regional/local gas transmission/distribution sections, and in the railroad network only. These sections are not contestable due to sunk costs, high entry lags expected and a probable short price adjustment lag. They are identified as bottlenecks which should be regulated. The function of system operators in energy and railroad are closely related to the non contestable monopolistic networks.
Das Leistungssystem der Destinationen wird zukünftig aus einzelnen Angebotsbausteinen bestehen, die potentiell an jedem Ort dieser Erde vom Kunden in Anspruch genommen werden können. Die normative Kraft dieser grenzenlosen (touristischen) Destination besteht aus einer tourismustypischen Grundausrichtung, deren sensueller Kern in einer profilierten Touristischen Region liegt. Als sensualisierte Marke löst sich diese Touristische Region von ihren Grenzen und steuert markt- und wettbewerbsorientiert ein Netzwerk destinationstypischer Angebote.
Die Studie untersucht Möglichkeiten, durch Optimierung Energie einzusparen und sich weitgehend auf erneuerbare Energien zu stützen.
Die vorliegende Diplomarbeit entstand im Rahmen eines Praxissemesters bei der Nike Deutschland GmbH und stellt das Sportsponsoring aus Sicht eines Sportartikelherstellers dar.
This paper analyzes conditions for existence of a strongly rational expectations equilibrium (SREE) in models with private information, where the amount of private information is endogenously determined. It is shown that the conditions for existence of a SREE known from models with exogenously given private information do not change as long as it is impossible to use the information transmitted through market prices. In contrast, these conditions are too weak, when there is such learning from prices. It turns out that the properties of the function which describes the costs that are associated with the individual acquisition of information are important in this respect. In case of constant marginal costs, prices must be half as informative than private signals in order for a SREE to exist. An interpretation of this result that falls back on the famous Grossman–Stiglitz–Paradox is also given.
This paper traces the profound decline in German unionism over the course of the last three decades. Today just one in five workers is a union member, and it is now moot whether this degree of penetration is consistent with a corporatist model built on encompassing unions. The decline in union membership and density is attributable to external forces that have confronted unions in many countries (such as globalization and compositional changes in the workforce) and to some specifically German considerations (such as the transition process in postcommunist Eastern Germany) and sustained intervals of classic insider behavior on the part of German unions. The ‘correctives’ have included mergers between unions, decentralization, and wages that are more responsive to unemployment. At issue is the success of these innovations. For instance, the trend toward decentralization in collective bargaining hinges in part on the health of that other pillar of the dual system of industrial relations, the works council. But works council coverage has also declined, leading some observers to equate decentralization with deregulation. While this conclusion is likely too radical, German unions are at the cross roads. It is argued here that if they fail to define what they stand for, are unable to increase their presence at the workplace, and continue to lack convincing strategies to deal with contemporary economic and political trends working against them, then their decline may become a rout.
This paper discusses the interdependencies that exist between vertically-linked industries in the (Spence-)Dixit-Stiglitz model of monopolistic competition. The main objective is to develop a concept for quantifying the magnitude of sectoral coherence in models of the New Economic Geography. It is motivated by the suggestion, by Venables (1996), that 'strategic industries' be identi®ed in terms of their agglomeration potential. Using a partial-analytic approach, we focus on inter-industrial relations in a closed economy to draw conclusions regarding international trade. We ascertain that two factors have an impact upon the strength of industrial linkages: 1) the monopolistic scope of intermediate suppliers, in terms of (technical) substitution elasticity; and the share in downstream costs for intermediates. Within a simulation study, this paper applies this new theoretical concept to eight basic industries across ten European countries.
An empirical analysis of various waves of the ALLBUS social survey shows that union density fell substantially in western Germany from 1980 to 2004 and in eastern Germany from 1992 to 2004. Such a negative trend can be observed for men and women and for different groups of the workforce. Regression estimates indicate that the probability of union membership is related to a number of personal and occupational variables such as age, public sector employment and being a blue collar worker (significant in western Germany only). A decomposition analysis shows that differences in union density over time and between eastern and western Germany to a large degree cannot be explained by differences in the characteristics of employees. Contrary to wide-spread perceptions, changes in the composition of the workforce seem to have played a minor role in the fall in union density in western and eastern Germany.
Abstract. The ecological literature suggests that biodiversity reduces the variance of ecosystem services. Thus, conservative biodiversity management has an insurance value to risk-averse users of ecosystem services. We analyze a conceptual ecological-economic model in which such management measures generate a private benefit and, via ecosystem processes at higher hierarchical levels, a positive externality on other ecosystem users. We find that ecosystem management and environmental policy depend on the extent of uncertainty and risk-aversion as follows: (i) Individual effort to improve ecosystem quality unambiguously increases. The free-rider problem may decrease or increase, depending on the characteristics of the ecosystem and its management; in particular, (ii) the size of the externality may decrease or increase, depending on how individual and aggregate management effort influence biodiversity; and (iii) the welfare loss due to free-riding may decrease or increase, depending on how biodiversity influences ecosystem service provision.
Systemanalyse für Softwaresysteme ist ein Manuskript zum Selbststudium und zur Begleitung von Lehrveranstaltungen. Es vermittelt eine Einführung in die Systemanalyse in diesem Informatik-Kontext. Systemanalyse wird dargestellt als ein zielorientiertes Vorgehen mit vielfältigen Konkretisierungs- und Abstraktionsaktivitäten. Die Vorgehensweise wird anhand von Beispielen erläutert.
This paper examines whether the attacks on the World Trade Center and the Pentagon on September 11th, 2001 have influenced the job prospects of Arabs in the German labor market. Using a large, representative database of the German working population, the attacks are treated as a natural experiment that may have caused an exogenous shift in attitudes toward persons who are perceived to be Arabs. Evidence from regression-adjusted difference-in-differences-estimates indicates that 9/11 did not cause a severe decline in job prospects. This result is robust over a wide range of control groups and several definitions of the sample and the observation period. Several explanations for this result, which is in line with prior evidence from Sweden, are offered.
Datenmodelle sind ein zentraler Bestandteil betrieblicher Informationssysteme. In der Praxis eingesetzte Datenmodelle erreichen oft eine erhebliche Komplexität. Eine Möglichkeit zur Reduktion der Komplexität besteht darin, gleiche oder ähnliche Teilstrukturen zu identifizieren. Durch Ausnutzung solcher Strukturanalogien kann dann das Datenmodell vereinheitlicht und vereinfacht werden. Ziel dieses Aufsatzes ist es, die bestehenden Ansätze zur Definition, Identifikation und Ausnutzung von Strukturanalogien in Datenmodellen weiterzuentwickeln.
Dieses Papier präsentiert deskriptive Evidenz zur Struktur von Ich-AG-Gründungen und Gründern aus dem Arbeitsagenturbezirk Lüneburg. Die Ergebnisse basieren auf einer Befragung aller Gründer, die zwischen Juni 2004 und Februar 2005 selbstständig geworden sind und von der Arbeitsagentur Lüneburg gefördert wurden.
Reviewing the development of network access charges in the German electricity market since 2002 reveals significant variation. While some firms continually increased or decreased their access charges, a variety of firms exhibited discontinuous behavior with price changes in both directions. From an economic viewpoint this price setting turbulence is astonishing because grid operators are non-contestable natural monopolists, which in this time period were regulated by Negotiated Third Party Access (NTPA). Depending on the effectiveness or ineffectiveness of NTPA, expected behavior would be either regulated average cost prices or monopoly prices, but not the observed turbulence. Although in 2005 NTPA scheme was replaced by a Regulated Third Party Access (RTPA) scheme with a regulator, an analysis of the factors influencing the price setting behavior within this period offers valuable information for the new regulator and the still discussed new incentive regulation, which is expected to start in 2009. Using multivariate estimations based on firm data covering the years 2000-2005, we test the hypotheses that asymmetric influence of regulatory threat, different cost and price calculation knowledge, strategic use of structural features and the obligation to publish specific access charges have influenced the electricity network access charges in Germany.
This paper aims to determine if the contingent valuation method (CVM) can provide valid results useful in policy-making. This will be investigated by using a CV study that captures the willingness to pay (WTP) for the municipal cultural supply in Lueneburg, Germany. In contrast to previous CV studies that included a wide range of descriptive statistics, the empirical analysis of the current study focuses on multivariate analysis to explore the factors associated with the WTP. The results reflect current hypotheses in cultural economics. Thus, higher education levels and higher income are positively correlated with higher WTP. While the results indicate a highly significant impact of non-use values on the WTP for cultural goods across the different regression models, the findings for some variables differ considerably in magnitude across different regression models.
In this paper, we conduct a pan-European efficiency analysis to investigate the performance of European railways with a particular focus on economies of vertical integration. We test the hypothesis that integrated railways realize economies of scope and, thus, produce railway services with a higher level of efficiency. To determine whether joint or separate production is more efficient, we apply a Data Envelopment Analysis super-efficiency bootstrapping model which relates the efficiency for integrated production to a reference set consisting of separated firms which use a different production technology. We find that for a majority of European railways economies of scope exist.
Das Ziel dieser Arbeit war es, ein Lernarrangement (=Modul) zur Gesundheitsförderung durch „Emotions-zentrierte Selbstreflexion und kollegiale Supervision“ zu entwickeln, zu erproben und hinsichtlich seiner Effekte auf die Gesundheit und Leistungsfähigkeit angehender Sozialassistentinnen und Erzieherinnen zu überprüfen. Mit dieser Untersuchung wurden außerdem erstmalig gesundheits- und leistungsrelevante Persönlichkeits- und Verhaltensvariablen angehender Sozialassistentinnen und Erzieherinnen erhoben, die als Ressourcen, Hilfen und Schutzfaktoren für die gesundheitsförderliche Bewältigung der beruflichen und privaten Anforderungen von besonderer Bedeutung sind. Vor diesem Hintergrund wurde auch das Training der „Emotions-zentrierten Selbstreflexion und kollegialen Supervision“ konzipiert. Neben einer generellen und differenziellen Wirkungsanalyse im Hinblick auf das Modul „Emotionszentrierte Selbstreflexion und kollegiale Supervision“, realisiert durch ein Vorher-Nachher-Kontrollgruppen-Design an einer Stichprobe von knapp 400 Teilnehmerinnen, leistet die vorliegende Untersuchung vor allem einen Klärungsbeitrag darüber, über welche gesundheitsdienlichen Ressourcen Erzieherinnen und Sozialassistentinnen während ihrer Ausbildung verfügen, welche Beziehung zwischen diesen Ressourcen bestehen und welche Skalen sich für eine Eignungsanalyse eignen würden. Ferner wurde ein Instrument zur Erfassung der berufsspezifischen Selbstwirksamkeit von Erzieherinnen und Sozialassistentinnen in Anlehnung an ein Berufseignungsinventar für das Lehramtsstudium entwickelt und hinsichtlich seiner Korrelationen zu den bereits erprobten Skalen überprüft. Die erhobenen Persönlichkeits- und Verhaltensvariablen der Erzieherinnen und Sozialassistentinnen unterstreichen die Relevanz einer frühzeitigen Intervention zur Stärkung personaler Ressourcen, vor allem deshalb, weil einige Erzieherinnen und Sozialassistentinnen nur über besonders gering ausgeprägte personale Ressourcen verfügen. Wichtig wäre vor allem, dass schon zu Beginn der Ausbildung angehende Sozialassistentinnen und Erzieherinnen ihre Passung zwischen den künftigen Berufsanforderungen und ihrem individuellen Eignungsprofil selbst diagnostizieren und sie mit differenziellen Maßnahmen begleitet werden, damit sie sich in eine für sie und ihre Berufsaufgaben günstige Richtung entwickeln können. Gezielte Selbstreflexionen emotionsrelevanter Tagesereignisse und kollegiale Supervision sollten als ein Modul in Aus- und Fortbildung zur Steigerung der Reflexionsfähigkeit, der emotionalen Kompetenz und anderer personaler Ressourcen implementiert und intensiv trainiert werden.
Subaquatic ammunition dumpsites of both, conventional as well as chemical ammunition do practically exist in every single ocean and even in a significant number of inland waters. Most of these dumpsites are based on related post world war dumping actions, when victorious and defeated states had to get rid of their enormous surplus stocks of ammunition and especially the not easy to be handled chemical warfare agents like mustard, phosgene and even nerve agents. After first attempts of conventional destruction like burning, explosion or even simple emptying of chemical agents into pits or holes in the ground, those attempts soon emerged to be very time-consuming and dangerous. Adequate destruction technologies of today’s standards like detonation chambers or plasma kiln did just not exist at that time. The persons in charge soon focused on a much more promising solution attempt: the dumping of this ammunition into surrounding water bodies. In the case of the post World War II dumping actions, the focusing on the former deep water sites soon turned out to be not practicable, based on related enormous costs and logistical problems. The Baltic Sea – with maximum water depths of about 150 m – seemed then to represent the easiest way to get rid of the problematic ammunition. By these activities 65,000 to up to 300.000 tons of chemical ammunition ended up in the Baltic Sea. Concerning conventional ammunition like water mines, torpedo warheads, high explosive devices etc., there is practically no information available but experts assume at least another 100.000 tons of conventional material in the Baltic Sea. Environmental aspects and the issue of protection of the sea were – like in other cases of subaquatic dumping actions worldwide – completely ignored at that time. Nevertheless, subaquatic dumping actions took place until the late 1980ies. Today these dumping sites – whether based on conventional or on chemical ammunition – do represent a very problematic and highly dangerous heritage to present and future generations: Corrosion of the containers and shells results in a not to be forecasted diffuse emission or rather leaking of the ammunition contents into the water body. Substances that are in most cases highly or even extremely toxic for humans, flora as well as fauna contaminate the marine environment with mostly unknown toxicological and ecotoxicological effects. The majority of these substances are known to have carcinogenic, teratogenic and/or mutagenic effects and practically nothing is known about the potential of these substances to end up in the food chains. Especially in recent years there are more and more findings of significantly increased arsenic values in fish that cannot be explained but there are strong signs that these values are based on ammunition dumpsites. Besides the mentioned toxicological and ecotoxicological effects, there are further significant risks as e.g. the possible access to the ammunition also in the context of terrorist and right-wing extremist activities, the continuous catching of and resulting injuring of fishermen by ammunition, the constant endangering of the civil and commercial shipping by direct contact or rather too close convergence to dumped ammunition especially in the context of self detonation or a sudden release of significant amounts of these substances e.g. in the context of an accident and last but not least the uncontrollable landing of containers and ammunition as well as already flushed out contents on coasts and beaches. Basically can be stated that there is still a significant need of action and scientific investigation in the general topic of subaquatic ammunition dumpsites and that related measures have to be taken immediately – especially concerning our sense of responsibility for future generations.
Als Fallstudie wird im ersten Paper der Einsatz der Szenarioanalyse als ein zentrales Element des Forschungsdesigns im Projekt „Sustainable University“ beleuchtet. Mit einem formalen Ansatz wurden Szenarien zum zukünftigen Umfeld der Hochschullandschaft entwickelt. Dieses Paper zeigt detailliert die notwendigen Denkschritte bei der Szenarioentwicklung auf und hilft zu verstehen, an welchen Punkten Integrationsschritte in Bezug auf Wissensarten und Perspektiven unterstützt und geleistet werden und somit auch (soziale) Lernprozesse gefördert werden können. Ferner werden die konkreten Ergebnisse der Szenarioanalyse vorgestellt und diskutiert. Zur Untersuchung von Lerneffekten wird die Methode der Szenarioanalyse in einen formalen Bildungskontext transferiert. Das zweite Paper leistet einen konzeptionellen Beitrag. Einleitend werden spezifische individuelle Kompetenzen diskutiert, die aus der Perspektive der Bildung für eine nachhaltige Entwicklung zum Umgang mit dem Klimawandel als komplexes Nachhaltigkeitsproblem und zu einer aktiven Teilnahme an Transformationsprozessen der Gesellschaft wichtig sind. Die Kompetenzen, wie proaktives Denken, der Umgang mit Unsicherheiten und unterschiedlichen Wissensbeständen sowie das vernetze Denken konnten hier beschrieben werden. Anschließend werden zwei Forschungsmethoden, der Syndromansatz und die Szenarioanalyse, für den Kontext der formalen Bildung nutzbar gemacht, und es wird theoretisch abgeleitet, wie in diesen Lernsettings die eingangs identifizierten Kompetenzen gefördert werden können. Die Szenarioanalyse bietet beispielsweise beim Denkschritt der Entwicklung von Zukunftsprojektionen großes Potential für Reflexionsprozesse oder die Integration von Wissen und Perspektiven zur Förderung der Kompetenz des proaktiven Denkens in Alternativen. Die diskursive Bewertung von Konsistenzen während der Szenarioerstellung birgt ähnliches Potential zur Förderung des vernetzten Denkens. Im dritten Paper wird ein Messinstrument für die Kompetenz des vernetzen Denkens (systems thinking) entwickelt. Es leistet einen empirischen Beitrag zur Lehr-Lernforschung, respektive zur Kompetenzmessung im Bereich der BNE. Dieses Instrument erfasst mit Hilfe eines Similarity Judgment Tests (SJT) den Grad der Vernetzung von Konzepten eines bestimmten Kontextes, in dem konkreten Fall von Aspekten des Klimawandels. In einer prä-post-Studie wurden zwei Kontroll und zwei Versuchsgruppen, die an dem zuvor genannten Lernsetting im Rahmen von Seminaren an der Leuphana Universität Lüneburg teilgenommen haben, empirisch begleitet. Auch wenn keine statistisch signifikanten Veränderungen des vernetzten Denkens der Teilnehmenden nachgewiesen werden konnten, bedeutet das nicht, dass die zuvor abgeleiteten Einflüsse der Szenarioanalyse widerlegt sind. Hier sind weitere Studien und die Weiterentwicklung des Messinstruments nötig. Zudem wurde nur ein Teil möglicher Einflüsse auf die Kompetenzentwicklung untersucht. Für die Szenarioanalyse als Lernsetting lässt sich schlussfolgern, dass zum einen der Moderation von Reflexions- und Diskussionsprozessen während unterschiedlicher Phasen eine sehr wichtige Rolle zukommt und sie einen wesentlichen Einfluss auf Lernprozesse hat. Zum anderen ist den Phasen, in denen Lernen stattfinden kann, genügend Zeit einzuräumen, so dass transdisziplinäre oder interdisziplinäre Forschungsprozesse mit der Methode Szenarioanalyse auch das Potential für Lernprozesse entfalten können. So kann mit Hilfe der Szenarioanalyse ein Setting geschaffen werden, in dem individuelle mentale Modelle und Handlungsmuster hinterfragt und Kompetenzen im Umgang mit komplexen Problemen gefördert werden, und somit individuelles und soziales Lernen für eine nachhaltige Entwicklung stattfinden kann.
Die Steigerung ihrer Ressourceneffizienz ist heute für viele Unternehmen des produzierenden Gewerbes sowohl aus Gründen des Umweltschutzes als auch zur Steigerung ihrer Wettbewerbsfähigkeit ein wichtiges Anliegen. Als ein in vielfältiger Hinsicht geeignetes Planungsinstrument für das industrielle Energie- und Stoffstrommanagement hat sich in den letzten Jahren die in den 1990er Jahren entwickelte Methode der Stoffstromnetze erwiesen. Ihr Manko besteht hauptsächlich darin, dass bislang keine automatische Suche nach Systemkonfigurationen mit optimalem Ressourcenverbrauch möglich ist. Gängige Optimierungsmethoden des Operations Research wie die mathematische Programmierung sind hierfür prinzipiell geeignet. Aufgrund ihres hohen Abstraktionsniveaus lassen sie sich jedoch nur schwer in betriebliche Planungsprozesse, insbesondere in mittelständischen Unternehmen, einbinden. Daher wird in dieser Arbeit eine neuartige Methode für die Optimalplanung industrieller Produktionssysteme entwickelt, die die Vorteile der Stoffstromnetze mit denen der Parameteroptimierung verbindet: die stoffstromnetzbasierte Optimalplanung. Als formale Schnittstelle zwischen Stoffstromanalyse und Operations Research wird durch die Einbettung eines Stoffstromnetzes in ein Parameteroptimierungsproblem das stoffstromnetzbasierte Optimierungsproblem (SSNOP) definiert. Dabei wird deutlich, dass aus der methodischen Integration nur dann ein sinnvolles Planungswerkzeug resultiert, wenn auch die jeweiligen Modellierungsparadigmen von Stoffstromanalyse und Optimalplanung miteinander verschmolzen werden. Das SSNOP ermöglicht daher nicht nur die angestrebte Erweiterung des Stoffstrommanagements um den Aspekt der automatischen Systemoptimierung. Es induziert darüber hinaus einen Perspektivwechsel von der traditionell eher beschreibenden zu einer entscheidungsorientierten Stoffstromanalyse. Nur durch die systematische Berücksichtigung der Freiheitsgrade eines Produktionssystems in Form von vorhandenen oder potenziellen Handlungs- und Gestaltungsspielräumen entstehen Stoffstrommodelle, die gleichzeitig als Optimierungsmodelle einsetzbar sind. Weiterhin werden in dieser Arbeit konkrete Lösungsansätze für das SSNOP untersucht. In Abhängigkeit von den Eigenschaften des eingebetteten Stoffstromnetzes gibt es zwei Möglichkeiten für die Optimierung: Einerseits die algebraische Reformulierung als mathematisches Programm, welches anschließend mit analytischen Optimierungsalgorithmen gelöst werden kann, andererseits die Anwendung direkter Suchalgorithmen im Rahmen einer simulationsbasierten Optimierung. Weiterhin wird ein Optimierungsmodul für eine stoffstromnetzbasierte Stoffstromanalysesoftware konzipiert, welches beide Lösungsansätze integriert. Mittels numerischer Experimente wird schließlich die Eignung verschiedener direkter Optimierungsalgorithmen zur Lösung des SSNOP untersucht.
In den Jahren 2006 und 2007 wurden auf dem Gebiet der Lüneburger Heide nach einer Vorstratifizierung im Rahmen ausgedehnter Feldforschung Umweltdaten für die stark bedrohte Spinnenart Eresus kollari Rossi 1846 und die eurytope Spinnenart Trochosa terricola Thorell 1856 erhoben. Ziel der Arbeit war es, die Habitatbindung beider Arten zu beschreiben und Heidepflegemaßnahmen vor allem für erstere zu benennen, um zu ihrem dauerhaften Erhalt beizutragen. Außerdem sollten beide Arten auf dem gleichen Standort in ihren Habitatansprüchen verglichen werden. Mit Hilfe der vorliegenden Untersuchungen konnte die spezifische Habitatbindung von E. kollari in der Lüneburger Heide beschrieben werden. Heidepflegemaßnahmen, die dazu führen, dass die organische Auflage des Bodens gering, die Temperatur auf Höhe der Röhren der Tiere (in 10 cm Tiefe) hoch und die Heidebedeckung gleichzeitig relativ groß ist, entsprechen den ermittelten Mikrohabitatansprüchen der Art Eresus kollari. Der Nischenvergleich der stenotopen Art E. kollari mit der eurytopen Art T. terricola zeigte, dass die beiden Arten sich hinsichtlich ihrer Habitatparameter nur in den drei Faktoren ‚Bedeckungsgrad Bäume‘, ‚Dicke der organischen Auflage‘ und ‚Bedeckungsgrad Gräser‘ unterschiedlich verhalten. Dabei stellt sich der Reaktionsraum von E. kollari wie eine Teilmenge desjenigen von T. terricola dar. Unter diesem Aspekt kann E. kollari nicht nur als Leitart sondern auch als Schirmart in der Lüneburger Heide dienen. Pflegemaßnahmen wie kontrolliertes Brennen und Schoppern, variabel in Zeit und Raum angewandt, erscheinen vor dem Hintergrund der Ergebnisse der Habitateignungsmodellierung als besonders geeignet, um langfristig die Mikrohabitatansprüche für E. kollari (aber auch für T. terricola) zu sichern. Angesichts des geringen Ausbreitungspotentials von E. kollari werden vielleicht manche geeignete Lebensräume nicht besiedelt. Ein Monitoring sowie (Wieder-) Besiedlungsexperimente auf geeignet erscheinenden Flächen sollten daher für den dauerhaften Erhalt der Art im norddeutschen Raum in naher Zukunft ausgeführt werden.
In the light of the concurrent loss of biodiversity, biodiversity and ecosystem functioning (BEF) research attracted a great deal of attention and emerged as one of the important fields of research in ecology. Since important ecological interactions such as competition occur between individuals, the understanding of individual tree growth was considered to be fundamental for forest related BEF research. Individual tree growth is determined by the above- and belowground interactions of a tree individual with its local neighbourhood. To obtain a deeper understanding of BEF relationships, I broadened the focus from individual tree growth (usually measured as diameter or biomass increment) to the arrangement and dynamics of the above-ground modules of trees in dependence of their local neighbourhood. More precisely, the main objective of the present thesis was to analyse the impact of tree diversity on individual tree growth, crown architectural and branch demographic variables. Thereby I considered crown architectural variables as important indicators of the competition for light. In addition, crown architectural variables impacted ecosystem services such as erosion control. Furthermore, the results of the present thesis contributed to the current discussion on species coexistence theories, which may be differentiated by two opposing views: one that relies on neutral processes and one that implicates a role for meaningful differences in the ecological strategy (niche) of co-occurring species. The studied forest ecosystems were the subtropical broad-leaved evergreen forests of southeast China, which have been under high human pressure due to a long history of intensive land-use. The area is of particular interest for BEF research due to the high species richness of woody plants, including many, yet poorly studied species, and due to the rough terrain with steep slopes, which cause severe soil erosion. The present thesis combines three observational with two experimental studies, applying the local neighbourhood approach along an age gradient from tree saplings to mature trees. In the Gutianshan National Nature Reserve (GNNR), I conducted two observational studies on permanent plots which were chosen according to a space-for-time substitution design. The aim of the first study was to reveal the effects of diversity (species richness, functional diversity) together with other biotic and abiotic variables on morphological growth parameters (crown area, crown displacement and stem inclination) of target trees of four tree species (Castanea henryi, Castanopsis eyrei, Quercus serrata and Schima superba). In the second study, the same target trees together with their neighbours were used to analyse the relation between stand related functional diversity and the horizontal and vertical structure of the canopy. The third study was conducted in a young secondary broad-leaved evergreen forest. Using two target species (Castanopsis fargesii and Quercus fabri), the role of diversity, intra- vs. inter-specific competition and the mode of competition (symmetric vs. asymmetric) on the target individuals was tested by analysing five-year radial growth increments. The two other studies were carried out in an experimentally established plantation, using saplings of four tree species (C. henryi, Elaeocarpus decipiens, Q. serrata and S. superba), which were planted in monoculture, twoand four-species combinations and in three densities. The fourth study focused on mechanisms of coexistence and the role of species richness, species composition, species identity and density on sapling growth. The fifth study tested the effect of sapling density and identity on the througfall kinetic energy, which represents a measure for the erosive power of rain. It was found that functional diversity does affect crown architectural and canopy related parameters of forests in the GNNR. However, no effects of species richness on radial-growth were detected in the younger forest. Since I also did not find strong effects of species richness on saplings in the experimental plantation, diversity effects may evolve at a later age stage. The importance of the diversity effect may be related reversely to that of species identity in an age gradient of forest stands. The findings suggest that different mechanisms of coexistence operate simultaneously but that their relative importance may shift through the life stages of trees. During the sapling stage, species-specific differences in growth and architectural traits support niche theory. In older forest stands, no species-specific differences in growth parameters could be detected. However, I did find effects of functional diversity on horizontal canopy structure. I conclude that mechanisms of coexistence may not only change with forest stand age, but may also differ for distinct traits. The present thesis, being the first to apply the local neighbourhood approach with regard to crown architecture and branch demography within the BEF field of research, stresses the importance of this individual based approach. Although the observed forest systems are very complex, crown architectural and canopy structural variables were found to be affected by diversity. The finding that the degree of erosive power of rain could be elucidated by crown architectural variables, encourages further studies to reveal possible relations between biodiversity and other ecosystem functions or services, which might be mediated by crown architectural and canopy structural variables.
Entrepreneurs and entrepreneurial firms are a frequent research topic in psychological research. However, the focus of this research has largely been on the entrepreneur as a person and on the entrepreneurs’ strategy for the business. By contrast, the entrepreneur as a leader and the entrepreneurial firm as a work environment for employees have received little attention. Therefore, this dissertation aims to integrate theoretic thoughts from organizational behavior research into entrepreneurship research. Specifically, I will focus on novelty creation within entrepreneurial firms and organizational phenomena which provide a context for employees in novelty creating activities. This dissertation adds to the literature as it provides insight in the effects of work environment facets on employees’ engagement in novelty creating activities in entrepreneurial businesses. In three empirical chapters, I will focus first on the effects of entrepreneurial orientation on efficiency of employee work in innovation projects. Second, I will look at a facet of organizational culture, the error management culture, and its effects on individual learning of employees. Last, I will focus on occupational roles of employees within small businesses and effects of these roles on responses to a questionnaire and on work in innovation projects. In all three empirical chapters I test my hypotheses in a sample of N = 40 entrepreneurial businesses and employees within these businesses. For my chapter on occupational roles this sample is complemented by two additional samples of college students. In sum, results indicate that the entrepreneurial business in all three chapters exerts significant influences on employee work. Furthermore, I show that employee participation in novel activities is positive for entrepreneurial businesses (Chapter 2: Correlation between employees’ and entrepreneurs’ evaluation of innovation project effectiveness: r = .44; p < .01; Chapter 3: Correlation between organizational level leaning and organizational growth in sales: r = .35; p < .01). Therefore, I suggest that research on the entrepreneurial firm as a context for work may contribute to our knowledge on success factors in entrepreneurship, and may therefore be a relevant direction of future research. Especially, it may be fruitful to investigate aspects of work in which entrepreneurial firms may differ from other, less entrepreneurial organizations.
The challenges of sustainable development have spurred the complexity of management reality, unveiling considerable risks and opportunities for companies. The past twenty years of development in management science and practice have refined the understanding of the linkages between corporate success and sustainability aspects of business. Nevertheless, numerous management tools and concepts have been criticised for failing to contribute to improved sustainability performance. Management accounting is an indispensable system for generating, preparing and providing information for recognising decision situations and informing decisions. Building on the relevance of information, sustainability accounting has received considerable attention in the past decade. Related research has emphasised the contribution of sustainability accounting to tackling sustainability challenges in specific settings. A systematic investigation of the role of sustainability accounting is virtually non-existent to date. To overcome this limitation and provide an insight into the practice of sustainability accounting and its role in sustainability management and ultimately in corporate success, this doctoral thesis approaches the question How does sustainability accounting contribute to improved information management and management control? The direct contribution is two-fold. First, a number of decision situations are explicated. Examples for such decision situations include utilising certain types of information for specific decisions, engaging various functions in different ways, etc. Making a decision within these decision situations was observed to contribute to achieving corporate goals. Second, the overarching view on the results reveals an interesting pattern. It is the existence of this pattern that supports the view that sustainability accounting can help companies in the pursuit of improved sustainability performance and (thereby) corporate success. The findings enable both practitioners and researchers gain an insight into how sustainability accounting can be deployed so that the company’s limited resources are focused on the crucial decisions in information management and management control. Subsequent recommendations are supported by up-to-date examples. The nature and the scope of the research constituting this doctoral thesis also highlight the path for future research to expand and refine the propositions made herein.
Der vielfältige Einsatz von unterschiedlichen organischen Substanzen in Haushalt, Landwirtschaft und Industrie hat zur Folge, dass diese eventuell in die aquatische Umwelt gelangen. Jede dieser Substanzen stellt potentiell eine Gefährdung der verschiedenen Wasserressourcen dar. Deshalb ist zur Sicherung der Trinkwasserqualität eine ständige und umfassende Überwachung der Ressourcen, die für die Trinkwasseraufbereitung verwendet werden, auf diese organischen Spurenstoffe notwendig. Als Ergänzung zum weitverbreiteten Target-Screening gewinnt das Non-Target-Screening mittels HPLC-MS in den letzten Jahren zunehmend bei der Überwachung von für die Trinkwasserherstellung genützter Wasserressourcen an Bedeutung. Diese Arbeit beschreibt neue Strategien für das Screening und die Identifizierung unerwarteter oder unbekannter organischer Spurenstoffe in Wasser mittels HPLC-QTOF-MS. Dabei werden alle Komponenten bei der Datenauswertung berücksichtigt, die mittels der verwendeten Analysenmethode detektierbar sind. Dies entspricht der Grundidee des Non-Target-Screenings. Dabei ist während des Screenings aufgrund der hohen Anzahl an detektierten Substanzen pro Probe eine Fokussierung auf wenige relevante Kontaminanten zwingend notwendig. Deshalb wird eine Probe nicht isoliert betrachtet, sondern es erfolgt eine vergleichende Betrachtung von mehreren Proben mit einer räumlichen, zeitlichen oder prozessbezogenen Beziehung. Die Effizienz der entwickelten Strategien konnte sowohl bei der Identifizierung von unbekannten Substanzen in Grundwasserüberwachungsproben als auch bei der Ermittlung von Oxidationsnebenprodukten von bekannten Kontaminanten (4- and 5-Methyl-1H-benzotriazol) bei der Ozonierung von Donauwasser erfolgreich gezeigt werden. Außerdem wurde für eine effektivere Unterstützung der Identifizierung von Substanzen das Datenbankkonzept DAIOS (Database-Assisted Identification of Organic Substances) angewandt. Schlussendlich können die beschriebenen neuen Strategien für das Screening und die Identifizierung organischer Spurenstoffe in Wasser für zahlreiche andere Anwendungsgebiete und Fragestellungen der Umweltanalytik, wie z.B. Überwachung von Altlastensanierung oder Prozessschritten der Trink- und Abwasseraufbereitung, eingesetzt werden.
The Ili Delta in Kazakhstan is an important ecosystem that offers crucial wetland habitats for several bird species. However, the Ili River, the Ili Delta and the Balkhash Lake are suffering from water shortage due to climate change and human activities. The desertification of the Aral Sea, an obvious point of comparison to the Balkhash region, also involved the degradation of wetland habitats and the related loss of many bird species relying on these habitats. Therefore, water shortage at the Ili Delta may also be the reason for the loss of wetland habitats and bird species. In this study, bird species numbers, species abundances as well as bird diversity at different habitats in the Ili Delta were examined. There are many habitat types provided by the Ili Delta, for example reed bed vegetation, Tugay forest, bare soil floodplains along rivers and steppe. The results of this study showed that the central delta region with habitats of submerged reed vegetation showed the highest number of bird species and the greatest diversity. Threatened bird species at the Ili Delta were also observed only in these wetland habitats. Steppe habitats showed the lowest numbers of bird species and the lowest bird diversity. In general, all habitats at the Ili Delta are important for the ecosystem and essential for the bird species that depend on them for their survival. With expansion of arid steppe habitats due to water shortage, however, previous wetland habitats may be lost. Moreover, bird species that depend on these wetland habitats may also be lost. Therefore, protective measures for the Balkhash region in general and the wetland habitats at the Ili Delta and its distinct avifauna in particular are urgently needed.
Sustainability aims at justice in a threefold sense: intragenerational justice, intergenerational justice, and justice towards nature. However, the justification, specific content and practical implications of justice claims and obligations in the sustainability context often remain underspecified. This dissertation therefore asks: How can the concept of justice be structured systematically? How can justice be specified in the context of sustainability? Which specific problems of justice arise in sustainability policy? And what are the respective contributions of (sustainability) economics and (sustainability) ethics? The five papers of this cumulative dissertation approach these issues from different angles, working at the conceptual level and at the level of cases from biodiversity and fishery policy. In Paper 1, a formal conceptual structure of justice is developed, which lists the conceptual elements of justice conceptions: the community of justice including claim holders and claim addressees, their claims (and corresponding obligations), the judicandum (that which is to be judged as just or unjust), the informational base for the assessment, the principles of justice, and on a more practical level, the instruments of justice. By specifying these conceptual elements of justice, it is possible to analyse and compare different conceptions of justice. In Paper 2, the normative dimension of sustainability is discussed in terms of justice. Based on the identification of certain core characteristics of the concept of sustainability, we determine the specific challenges of justice in the context of sustainability along the conceptual structure of justice (from Paper 1). Inter alia, we show that sustainability calls for the integration of justice claims in the relationships with contemporaries, future humans and nature in a non-ideal context characterized by uncertainty, systemic mediation and limits. Paper 3 addresses the contribution of economics to the assessment of trade-offs between intergenerational and intragenerational justice. Economic analysis can delineate the opportunity set of politics with respect to the two justice objectives and identify the opportunity cost of attaining one justice to a higher degree. While the two justices are primary normative objectives, the criterion of efficiency - when directed at the attainment of these justice objectives - has the status of a secondary normative objective. Paper 4 constitutes a case study, reconstructing the ´biopiracy´ debate from a justice perspective. The paper links to the so called Access and Benefit-Sharing framework of the Convention on Biological Diversity, and addresses the question, which problems of justice arise regarding the utilization of genetic resources and traditional knowledge, especially if associated with patenting. It is shown that the predominant perspective of justice-in-exchange is insufficient and therefore complementary conceptions, namely of distributive justice, corrective justice and structural justice have to be taken into account. Paper 5 empirically assesses the justice notions of stakeholders in the Newfoundland fishery, building on qualitative semi-structured interviews and a combination of inductive and deductive coding. A central result is that inshore fishers are seen as the main claim holders, with a claim to participate and being listened to, and the opportunity to make a living from the fishery. Recognition, participation and distribution are all important domains of justice in the context of the Newfoundland fishery. The paper also discusses the relationship between normative theorizing and empirical justice research. Overall, this thesis integrates ideal and non-ideal normative theorizing, economic analysis, empirical justice research and hints at institutional implementation in the debate on sustainability and justice.
Die Webbasierte Rehabilitationsnachsorge (W-RENA) unterstützt Patienten psychosomatischer Rehabilitation zum einen in der Vorbereitung auf den Transfer von in der Klinik erworbenen Strategien in den poststationären Alltag. Den Kern der Intervention bildet zum anderen die 3-monatige Begleitung über das Internet bei diesem Prozess des Anwendungslernens im Alltag. Damit bietet die W-RENA zugleich auch eine Überbrückung der Wartezeit auf einen ambulanten Therapieplatz, denen Patienten psychosomatischer Rehabilitation häufig ausgesetzt sind. Diese Arbeit fokussiert die Rolle von Selbststeuerungskompetenzen im Rahmen dieses Lerntransfers und prüft, ob die W-RENA hier eine förderliche Funktion einnimmt. Die Messung von Selbststeuerungskompetenzen erfolgte zu 4 Erhebungszeitpunkten mit dem SSI-K3 (Kuhl, 2004). Eindeutige Effekte konnten für die Subskalen Selbstregulation und Selbstzugang nachgewiesen werden. Dass Patienten der W-RENA stationär erlernte Strategien im poststationären Alltag auch 12 Monate nach Entlassung signifikant häufiger anwenden als Patienten der Kontrollgruppe konnte mit dem KFB-EQUA (Schmidt, 2003) nachgewiesen werden.
This PhD thesis examines the connections between sustainability knowledge management (SKM) and sustainability management tools in small and medium-sized enterprises (SMEs). While previous literature has established that knowledge is essential for the application of sustainability management tools, the effects of such tools on knowledge management are under-researched in the sustainability context. Drawing on multiple academic papers and utilizing various research methods, including a systematic literature review, several quantitative surveys and a multiple case study approach, the thesis systematically examines how such tools can facilitate the identification, acquisition, conversion, application and retention of sustainability knowledge, and potentially lead to the improvement of SKM effectiveness in SMEs. Furthermore, it examines how support functions for sustainability management tools and SKM correspond with each other. The findings reveal that sustainability management tools facilitate the SKM processes (identification, acquisition, conversion, application and retention), and align with the support factors (e.g. top management support, shared vision, employee qualifications) to advance SKM in SMEs. Particularly, such tools permit the institutionalization of sustainability knowledge into the daily routines and practices in SMEs. Additionally, tools create a support structure for SKM, embedding and preserving sustainability knowledge in documents, policies, procedures and norms for an enterprise´s collective knowledge for sustainability management. The thesis concludes with complementing areas of future research and offers practical implications for SME management.
The importance of a social perspective on the relationships between humans and nature has longbeen acknowledged. The field of social-ecological systems research in particular is striving toachieve a holistic understanding of human-nature relationships by balancing social andecological perspectives. Here I sought to develop a social understanding of the Saxon area inCentral Romania, by exploring aspects of human-nature relationships as seen from theperspective of local people. To this end, I employed the concepts of social-ecological systems(SES), ecosystem services (ES) and cultural landscapes to assess perceptions of locals throughempirical case studies.I first conducted a literature review to acquire an overview of a particular type of human-naturerelationship mediated by non-consumptive use and non-use values (“cultural ecosystemservices”). Second, to isolate and address the interaction from the social system to the ecologicalsystem, I investigated the different ways locals perceived the role of landscapes in SouthernTransylvania. I conceptually mapped these landscape preferences by revealing their potentialland use and management implications. Third, to approach the human-nature relationship fromthe ecological system to the social system, I studied the flow of ES to disaggregated humanbeneficiaries. Specifically, I studied which factors, beyond ecosystem processes and functions,influenced nature derived human well-being from the perspective of potential beneficiaries. Iconceptualised the mediating role of a range of contextual factors underpinning the currentdistribution of ES, with regard to the relation between ES and human well-being. Fourth, inorder to explore an example of bidirectional human-nature relationship, I studied the particularcase of human-carnivore coexistence and the suite of mechanisms shaping it.Despite building throughout this thesis a more complex and in-depth understanding of the humandimensions of the studied system, I chose four main cross-cutting themes to explain the human-nature connection in Southern Transylvania. These four themes may serve as pillars of a sociallyminded understanding, as well as potential research and policy foci. First, the values held bylocals are key for understanding the endemic human-nature relationships and should not beoverlooked in future social-ecological assessments or policy interventions. Second, the culturallandscape of Southern Transylvania is both a physical and virtual space of social-ecologicalinteraction fostering human-nature experiences and social-ecological knowledge integration.Third, the identified diversity of the social system in terms of landscape aspirations and ESbeneficiaries is expanding the range of human-nature connections, but at the same time, may infuture be a source of conflict or disconnection if not managed appropriately. Finally, small-scalefarmers, through their interactions with the land and resultant belief system, play a major role inmaintaining the human-nature relationships, but their values and lifestyle are threatened.
This thesis makes an important contribution to better understanding biodiversity and ecosystem function relationships across trophic levels in forests - aspects that are still underrepresented in BEF research. Ongoing biodiversity loss can be expected to change important trophic interaction pathways in these ecosystems, making increased efforts in exploring the mechanisms underlying, and the drivers determining, the impact of trophic complexity on the relationships between biodiversity and ecosystem functioning a crucial objective for holistic approaches to BEF research.
In 1999 David Elstein delivered a lecture series examining the evolvement of UK broadcasting policy from 1949 to 1999. His sharp analysis is a valuable contribution to the post-war devel-opment of the British broadcasting system and unfolds many topical issues in current media policy debates.
Despite the great progress that has been made in the prophylaxis of oral diseases over the past decades, dental caries and periodontal diseases remain major challenges in the field of dentistry. Biofilm formation on dental hard tissues is strongly associated with the etiology of these oral diseases. Therefore, the process of bioadhesion and biofilm formation on tooth surfaces is of particular interest for dental research. The first stage of bioadhesion on dental surfaces is the formation of the pellicle layer. This mainly acellular film, composed largely of adsorbed proteins, glycoproteins, and lipids, is distinguished from the microbial biofilm (plaque). As the interface between teeth and the oral environment, the pellicle plays a key role in the maintenance of oral health and is of great physiological and pathophysiological importance. On the one hand, the pellicle shows protective properties for the underlying dental hard tissues. On the other hand, it also serves as the basis for dental plaque and therefore, for the development of oral diseases such as caries and periodontitis. Hydrophobic interactions, which are governed by lipophilic substances, are of high relevance for bacterial adherence. Therefore, pellicle lipids, which are a significant constituent of this biological structure, are an interesting target for dental research, as they could modulate oral surfaces, influence microbial interactions, and potentially impede bacterial adherence. Compared to the extensive work on the pellicle´s ultrastructure and protein/amino acid composition, little attention has been given to its lipid profile. Knowledge of the lipid composition of the pellicle may provide insight into several oral pathological states, including caries, dental erosion, and periodontal disease processes and could contribute to novel approaches in preventive dentistry. The principle aim of this thesis was the comprehensive characterization of the fatty acid (FA) profile of the in situ formed pellicle layer. This includes the influence of pellicle maturation on the FA profile as well as intra- and interindividual differences. Furthermore, investigations on the effect of rinses with edible oils on the pellicle´s FA composition were a focus of this work. For these purposes, an analytical method based on a combination of innovative specimen generation and convenient sample preparation with sensitive mass spectrometric analysis was successfully developed and comprehensively validated within this thesis. Pellicle samples were formed in situ on bovine enamel slabs mounted on individual upper jaw splints. After a comprehensive sample preparation, gas chromatography coupled with electron impact ionization mass spectrometry (GC-EI/MS) was used in order to characterize qualitatively and quantitatively a wide range of FA (C12-C24). The individual FA profiles of pellicle and saliva samples collected from ten research participants were investigated. The relative FA profiles of the pellicle samples gained from the different subjects were very similar, whereas the amount of FAs showed significant interindividual variability. Compared to the pellicle´s characteristic FA profile, higher proportions of unsaturated FAs were detected in the saliva samples, highlighting that FAs available in saliva are not adsorbed equivalently to the pellicle layer. This, in turn, shows that pellicle formation is a highly selective process that does not correlate directly with salivary composition. Additionally, pellicle samples collected after 3, 30, 60, 120, and 240 min of intraoral exposure were analyzed. It could be shown that pellicle maturation has only a minor impact on the FA composition. However, the FA content increased substantially with increasing oral exposure time. Modifying the pellicle´s lipid composition by using edible oils as a mouthwash could alter the physicochemical characteristics of the pellicle and strengthen its protective properties by delaying bacterial adhesion. Therefore, the impact of rinses with safflower oil on the pellicle´s FA composition was determined. The application of rinses with safflower oil resulted in an accumulation of its specific FAs in the pellicle, thus representing a possibility for modifying the pellicle´s lipid profile. The present work is the first to apply a validated method that combines in situ pellicle formation, sample preparation, and the comprehensive determination of FAs via a sensitive analytical method. The results provide valuable information regarding the pellicle´s FA composition which closes an existing knowledge gap in pellicle research. A broader knowledge of the lipid composition of the pellicle contributes to the understanding of oral bioadhesion processes and may help facilitate novel approaches in preventive dentistry.
After being administrated to humans or animals, pharmaceuticals may be metabolized by a variety of mechanisms and pathways within the body. Once these compounds and/or their metabolites are excreted, they may undergo degradation in the aquatic environment. Unfortunately, a rapid and complete mineralization cannot always be guaranteed, whereas relatively stable transformation products (TPs) may be formed. The largest part of older studies focused on investigation of the elimination kinetics of parent compounds without considering the amount and chemical structure of individual TPs. Only recently, there is an increasing trend to deliver such information. Nevertheless, since drugs are defined as significant environmental pollutants, it is not only important to elucidate their TPs, but also necessary to investigate whether these formed compounds preserve the same mode of action as the parent compound or are even more toxic. Thus, two main objectives of this thesis can be formulated. Firstly, to highlight the concern originated by metabolites and transformation products of pharmaceuticals that contaminate the environment. Hereby, the already-published knowledge on TPs within a certain selection of drugs is assessed to exemplify the number and quality of the existing information on their TPs. Secondly, to particularly investigate the fate of the antibiotic ciprofloxacin (CIP). This is done by (a) evaluating the suitability and sustainability of the photolytic decomposition as an advanced water treatment technique, (b) monitoring the course of genotoxicity of the irradiated mixtures using a battery of genotoxicity and cytoxicity in vitro assays, and (c) considering the potential genotoxicity for CIP´s individual TPs by the employment of in silico approaches using quantitative structure activity relationships (QSAR) models. This thesis based on the results and conclusions of five articles, which can be found in the appendix. A systematic literature review was conducted on the current state of knowledge on pharmaceuticals and its derivatives in the environment. Two groups, namely antibiotics and anticancer drugs, were considered more closely with respect to the availability of chemical structures for their TPs. Furthermore, the photodegradation of CIP as well as a preliminary toxicity assessment of its identified TPs were investigated in three research papers. An extensive review with a table at its core shows the existing data on 158 TPs, which already have an assigned registry number in chemical abstracts service (CAS-RN), was presented. In total, 294 TPs, identified with chemical structures in the literature, were found for 15 compounds out of the 21 that were selected as target compounds. Eleven TPs, created from CIP, were identified by high-performance liquid chromatography/high-resolution multiple-stage mass spectrometry. It was detected that the transformation of CIP mainly occurred through substitution of fluorine, defluorination, hydroxylation of the quinolone core and the breakdown of the piperazine ring. Some of the identified TPs of CIP were predicted as genotoxic by QSAR analysis, while the experimental testing for a few genotoxic and cytotoxic endpoints showed that the potential of the resultant mixtures could be primarily dependent on the concentration of residual CIP. In contrast, irradiation mixtures were neither mutagenic in the Ames Test nor genotoxic in the in vitro Micronucleus Test. It is possible that the effect of the TPs was masked by antagonistic mixture interactions and/or they were not formed at effectively concentrations. Nevertheless, all of the identified TPs of CIP still retained the core quinolone moiety, which is responsible for the biological activity. Thus, a more comprehensive assessment, encompassing more genotoxic endpoints, chemical analysis characterization and exposure analyses, needs to be conducted. Information available on TPs demonstrates that already slight changes in treatment conditions and processes result in the formation of different TPs. Nevertheless, most of the transformation products could neither be identified nor fully assessed regarding their toxicity. This, in turn, presents a major challenge for the identification and assessment of TPs. Hence, from a practical and sustainability point of view, limiting the input of pharmaceuticals into effluents as well as improving their (bio)degradability and elimination behavior, instead of only relying on advanced effluent treatments, is urgently needed. Solutions that focus on this
Agricultural production of smallholder farmers in Myanmar is facing soil fertility degradation and in consequence, crop yields decline due to the imbalances of nutrient supply. In most cases, all above ground biomass is removed from the fields after harvesting the crops and during land preparation for the next crop. Higher temperatures also stimulate the higher mineralisation rates and released mineral nutrients are lost from fallow lands before sowing the next crops. Regarding the addition of mineral fertilizers, except for cash crops, farmers are reluctant to apply fertilizers for the crops that are sown for household’s self-sufficiency. In the Dry Zone, irrigated agriculture is available in recent years and farmers could overcome water scarcity through irrigation. With the availability of irrigation water, farmers could prolong the cropping period, nevertheless crop yields are decreasing year by year. In recent decades, research findings are indicating the benefits of biochar application for soil fertility improvement and food security. Smallholder farmers can produce biochar from agricultural by-products such as pigeon pea stems, cotton stems and rice husks by using biochar stoves. Large-scale production is possible by producing both biochar and thermal energy simultaneously, such as getting rice husk biochar and producing thermal energy by burning rice husks. By those means, environmental pollution due to the smokes from stubble burnings and the health hazards from smokes arise from kitchens can also be reduced. Present research was conducted to test the effects of the application of biochars produced from different crop residues together with NPK fertilizers on crop yields and soil properties in the rice-chickpea-cotton cropping system of the Central Dry Zone area of Myanmar during 2012 and 2013 cropping seasons at Shwe Daung Farm, Mandalay Division, Myanmar. Effects of biochar applications in combination with NPK fertilizers were compared with NPK fertilizer (without biochar) application and the control (without biochar and NPK fertilizers). Biochars used in the experiments were produced from three kinds of locally available raw materials (rice husk, rice straw and, pigeon pea stem) at temperature above 550°C by using a kiln made from a 200-Liter diesel barrel. Field experiments were conducted on sandy loam soil in the Central Dry Zone of Myanmar. After harvesting rice in 2012, chickpea was sown without application of both organic and inorganic fertilizers. After harvesting chickpea in 2013, cotton was sown on the same experimental plots. Treatments were rice husk biochar (Rh) 20 Mg ha-1 + NPK fertilizers; rice straw biochar (Rs) 20 Mg ha-1 + NPK fertilizers; pigeon pea stem biochar (Ps) 20 Mg ha-1 + NPK fertilizers; rice husk biochar and farmyard manure mixture (Rh biochar + FYM) 10 Mg ha-1 + NPK fertilizers; NPK fertilizers (without biochar); and the control (without fertilizer and biochar). Biochar weights represented fresh biochar weights. Equal rate of NPK fertilizers were applied in all treatments. However, fertilizer rates were different with respect to the crops. In rice experiment, 100:50:50 kg ha-1 rate of Urea (N): Triple Super Phosphate (P): Muriate of potash (K) was applied. In cotton experiment, 100:30:117 kg ha-1 rate of Urea (N): Triple Super Phosphate (P): Muriate of potash (K) was applied. Crop growth data, yield component data and yield data of each treatment were recorded. Soil samples from topsoil (0-0.2 m) were taken before starting the experiments, after harvesting rice and cotton, respectively, and analysed. A biogeochemical model, denitrification decomposition (DNDC) model, was used to estimate soil organic carbon storage and greenhouse gas emissions during crop growing seasons and to quantify the long-term impact of biochar applications on rice, chickpea and cotton yields.The results from soil analyses indicated that although initial soil pH was at 8.0 and pH values of biochars ranged between 8.0 and 10.0 soil pH after two years of biochar application did not increase. pH values were below 8.0. That value was lower than initial soil pH. That could be due to the effect of the change of cropping system from upland to lowland rice cultivation and the effects of biochar additions to the alkaline sandy loamy soil of the experimental site. Although total exchangeable cation value was not significantly different among the treatments, compositions of major cations were significantly different among the treatments. Exchangeable potassium increased in Rs biochar + NPK applied soils. Exchangeable sodium increased in control, and conventional NPK fertilizer applied soils. Reduction of soil bulk density from 1.8 g cm-3 to 1.6-1.7 g cm-3 occurred in biochar treatments compared to control and conventional NPK fertilizer application treatments. Positive changes of total carbon and total nitrogen of soils were found in biochar treatments compared to control and conventional NPK fertilizer application. Application of pigeon pea stem biochar + NPK fertilizers showed the highest crop growth and the highest yield in rice. The highest chickpea yield was obtained from the plot that applied rice husk biochar + NPK fertilizers. Cotton crop growth and yield was the highest in rice husk biochar and farmyard manure mixture + NPK fertilizer application. The lowest crop growth and yield was obtained from the control in cotton. The results of this study suggested that biochars from different biomass materials had different effects on soil properties and crop yields under different growing conditions and cultivated crops. Although the applied biochars had a high pH, soil pH did not increase after biochar applications. The growth and yield of tested crops were higher than that of the control and conventional NPK fertilizer application. Rice husk biochar and farmyard manure mixture + NPK fertilizer application can be assumed as a suitable soil amendment application under upland crop cultivation. Pigeon pea stems biochar + NPK fertilizers should be applied in rice cultivation. Rice husk biochar + NPK fertilizers and rice husk biochar-farmyard manure mixture + NPK fertilizers showed as the appropriate biochar soil amendments for the study area compared to rice straw biochar + NPK fertilizers and pigeon pea stem biochar + NPK fertilizers. Application of these biochars increased total exchangeable cations, reduced bulk density, increased organic carbon, regulated soil pH and, can easily be accessed by smallholder farmers by promising crop yields for sustainable agricultural production. Rice straw biochar + NPK fertilizers and pigeon pea stem biochar + NPK fertilizers also showed positive influences on soil fertility and crop growth. However, extensive application of those biochars might require large-scale productions and distributions. To obtain the detail information regarding the impact of biochar application on the agro-ecosystem and surrounding atmosphere, further research activities may need to carry out under different agricultural production conditions. When model fitness was tested, it was found that DNDC model was fit for the simulation of crop yields and soil organic carbon under the conditions of the experimental site. Simulation of soil organic carbon dynamics and crop yields for 30 years and 50 years after the addition of biochars in combination with NPK fertilizers showed that such applications could maintain the crop yields at the same level up to 50 years. That could maintain soil organic carbon at a level higher than conventional NPK fertilizer application. Regarding the simulation of GHGs emissions, the model simulated nitrous oxide emission close to actual emissions of agricultural soils of Myanmar. Simulated CH4 emissions from control and conventional NPK fertilizer application variant were consistent with the well-known emissions of Myanmar rice fields. To confirm the accuracy of simulated CH4 emissions from biochar applied soils, it may need field investigations and validations of model results. Simulated effects of rice husk-, rice straw- and pigeon pea stem fresh biomass applications and that of rice husk-, rice straw- and pigeon pea stem biochar applications on rice, chickpea, cotton yields and soil organic carbon (SOC) were compared. Objective of this simulation was to compare the effects of fresh biomass-applications and the application of biochars produced from the same biomass on crop yields and SOC by using DNDC model. The results showed that simulated rice yields of rice husk biochar and rice straw biochar applications were 33% and 31%, respectively, higher than that of pigeon pea green manure applications. However, simulated rice yield from pigeon pea stem biochar application was 4% higher than that of iv pigeon pea stem green manure application. Simulated chickpea yield from pigeon pea green manure treatment was the highest among all of biochar and biomass applications. Simulated cotton yields obtained from fresh biomass applications were lower than that of biochar applications. In estimating the future yields, all crop yields from rice husk and rice straw biomass applications were lower than that of rice husk and rice straw biochar applications in the initial year of simulation. However, in the following years, the yields remained at the same level up to the end of simulated years. In pigeon pea stem green manure application, crop yields were higher than the other treatments since the initial year up to the end of simulated years. Simulated SOC was lower in fresh biomass applications compared to biochar applications.
Members of Western organizations differ in various diversity attributes. In response, research aims to provide evidence-based recommendations on how to effectively manage diversity in teams. Within diversity research, the diversity faultlines approach has been particularly fruitful. It considers the impact of the alignment of multiple diversity attributes in teams. Strong diversity faultlines are associated with the emergence of relatively homogeneous subgroups in teams and have an overall negative impact on team processes and outcomes. This dissertation investigates factors that mitigate the detrimental consequences of strong diversity faultlines in teams, namely pro-diversity beliefs. It extends faultline literature beyond the conventional focus on processes and outcomes related to team members by emphasizing the leaders' perspective. The three empirical papers included in this dissertation systematically examine how strong pro-diversity beliefs can help unleashing the positive effects of team diversity despite strong faultlines. The first paper highlights the role of leaders' pro-diversity beliefs in mitigating the negative impact of diversity faultlines on two team processes: perceived cohesion and social loafing. Moreover, it compares the impact of socio-demographic faultlines (based on gender and age) and experience-based faultlines (based on team tenure and education level). Data was collected in a multisource field sample with 217 team members nested in 44 teams and the corresponding leaders. The second paper takes the impact of members' pro-diversity beliefs into account. It examines whether the impact of sociodemographic faultlines on performance is contingent on leaders' and members' pro-diversity beliefs. Moreover, the research group assumed that aggregate LMX would mediate this relationship. In a multisource data set obtained from 41 teams with 219 members and the corresponding leaders working for the German Ministry of Foreign Affairs, the investigators found partial support for their hypotheses. As expected, the impact of strong socio-demographic faultlines on diplomats' performance was least negative when both leaders and members held strong pro-diversity beliefs. The third paper zooms into processes and outcomes related to team leaders. It investigates how leaders' pro-diversity beliefs and their perceptions of members' prodiversity beliefs in teams with strong socio-demographic faultlines impact leaders´ task role assignment, performance expectation, and motivation. The research group conducted two experimental studies with students, one in Germany (N=55) and one in the US (N=134). Findings showed that strong pro-diversity beliefs held and perceived by leaders made them assign task roles that cross-cut rather than aligned with the subgroup structure created by faultlines. Moreover, leaders' perceptions of members' pro-diversity beliefs, but not their own beliefs, had a positive impact on their motivation, mediated by their performance expectation.
The effects of habitat fragmentation and land use changes are usually studied by relating patterns of genetic diversity and differentiation to environmental factors, habitat history, landscape structure, or to a combination thereof. However, these three drivers are rarely addressed simultaneously. In addition, these studies are usually carried out in conservation-driven contexts, and therefore tend to concentrate on hyper-fragmented landscapes and on rare or endangered species. However, how habitat fragmentation and land use affect widespread species in more typical landscapes has not been fully investigated. This thesis addresses these two gaps. Abax parallelepipedus, a flightless ground beetle with low dispersal power, was used as a model species to test how environmental factors, habitat history, and landscape structure affect genetic diversity and genetic differentiation in three study regions located across Germany. Although all of the study regions represent fairly typical rural landscapes for central Europe, each consisting of a complex matrix of land uses, they differ from one another in terms of environmental factors, habitat history, and landscape structure, and thus can serve as three test cases. In the first stage of the work, the investigator identified polymorphic microsatellite loci which could potentially be used to study genetic diversity and differentiation in A. parallelepipedus. She then developed PCR and genotyping protocols for two suites of loci, in the end selecting to use the set of 14 fully multiplexed loci for the study. After having developed the needed study system, she genotyped over 3300 beetles from 142 study sites. In her investigation of how environmental factors and habitat history affect genetic diversity and genetic differentiation, and found that genetic diversity was being driven by variables that could be related to population sizes rather than by habitat history. She also did not find evidence of an influence of habitat history on the genetic differentiation patterns. Although populations of A. parallelepipedus in the past were probably smaller due to deforestation, they apparently remained large enough to prevent rapid genetic drift. In addition, the researcher carried out a landscape genetics analysis of the genetic differentiation patterns found in each of her study regions, in which she examined the relationship between genetic differentiation and landscape structure. She tested whether she could find patterns of isolation by distance, isolation by resistance, or isolation by barriers in the study regions. No effects of land use or of fragmentation were found. Based on the importance of population sizes found in the previous study, combined with the beetle's known avoidance of non-wooded areas and its inability to cross roads, the investigator concludes that although there is probably little gene flow across the study regions, large population sizes are preventing the rapid development of genetic differentiation. Models simulating the development of genetic differentiation over time in populations of different starting sizes support this conclusion.
The dissertation project focuses on empirically investigating consumers' attitudes, motivations and purchasing decisions regarding sustainable products. The focus on this micro perspective, however, does not reflect consumers' roles within the transformation towards sustainable consumption. Therefore, the present framework paper puts the included papers into a greater context and evaluates the findings on a meta-level by applying an enhanced transition management theory. The analysis underlines that consumers' limited personal capabilities are an underlying reason for unsustainable practices. Therefore, the active engagement not only of consumers, but also of companies is required if the transformation is to be successful. If companies actively support consumers in making sustainable choices, consumers can engage in sustainable consumption with only low cognitive efforts. On this basis, genuine sustainable choices are enabled. The dissertation provides practical implications by highlighting potential measures which will help to promote sustainable products from niches to mainstream. In sum, the dissertation project enhances academic understanding of consumers´ sustainable purchasing behavior and reveals the potential of integrating such insights into the management of transformations towards sustainable consumption.
The research aims to assess the sustainability of rural electrification efforts based on off-grid photovoltaic (PV) systems in three Andean countries: Chile, Ecuador, and Peru. Although deployment of off-grid PV solutions for rural electrification began in the early 1990s in the Andean region, most of the projects turned out to be unsustainable and did not last. Prior efforts have addressed the different issues and barriers that plagued these projects and inhibited their sustainability. However, these prior analyses were mostly quantitative; systematic qualitative evaluations have been scarce. In this thesis, the researcher addresses the following research question: "Are the rural electrification programs (based on off-grid PV Systems) in the Andean countries sustainable?" In order to answer this research question, he conducted an exhaustive qualitative document analysis complemented by semi-structured expert interviews. The interviewees included experts from different ministries, project managers from leading Non-Governmental Organizations (NGOs), public and private companies ' representatives, supervisors, and researchers. Although the author also describes several relevant PV-based electrification efforts in the Andean countries, the research was aimed at providing an overall picture of the rural electrification efforts in these countries, rather than measuring the success or failure of specific projects. The gathered information allowed me to assess the sustainability of rural electrification efforts in the Andean countries. This assessment was based on a set of indicators corresponding to the four dimensions of sustainability considered in this thesis: institutional, economical, environmental, and socio-cultural. It was found that Ecuador and Chile have consistently failed to ensure mechanisms for the operation and maintenance of the deployed off-grid systems, which has made these solutions in poor Chilean and Ecuadorian communities inevitably unsustainable. Although Peru has adopted a cross-tariff scheme, the Peruvian case shows that ensuring the funding of off-grid PV solutions is not enough. Peruvian officials appear to be unaware of the importance of local participation (local values and lifestyles are constantly disregarded) and most of the projects have been designed without the participation and engagement of the communities, which has often led to project failures and payment defaults. Although each country has its particular challenges, it was found that the three Andean countries have consistently neglected the importance of strong formal institutions with a flexible and decentralized structure, which in turn significantly compromised the rural electrification effort in these countries.
European species-rich grasslands are threatened both by land use intensification as well as land abandonment. The studies shown in this thesis tested the possible use of ecological knowledge to ensure hay productivity whilst maintaining diversity of grasslands, with a view to informing ecological restoration. The overall approach was to understand interactions between plants, to study diversity effects on productivity, and mainly investigate how plant functional groups that arrive first in the system can create priority effects that influence community productivity both above- and belowground. A grassland field experiment was established and monitored for four years, in order to verify the effects of manipulating the order of arrival of different plant functional groups, as well as the sown diversity level on productivity and methane yield. The overall findings were: a) sowing legumes first created priority effects aboveground (higher biomass) and belowground (lower root length), plants invested less in roots and more in shoots, b) priority effects were more consistent below than aboveground, c) sown diversity did not affect aboveground biomass, d) the order of arrival treatments indirectly affected methane yield by affecting the relative dominance of plant functional groups. Since the researchers lack information on how legumes and non-legumes interact spatially belowground, (particularly related to root foraging) a controlled experiment was performed, using two grass species and one legume. The identity and location of the neighbours played a role in interactions, and the order plants arrived modulated it. When the focal species (grass) was growing with a legume it generally equated to the same outcome as not having a neighbour. Roots from the focal species grew more toward the legume than the grass neighbour, indicating a spatial component of facilitation. Since these studies involved root measurements, a method study was also conducted to verify how comparable and accurate are root length estimates obtained from different techniques. Results showed that the use of different methods can lead to different results, the studied methods did not have the same accuracy, and the automated methods can underestimate the root length. Overall, the results allow to conclude that different groups of plants arriving before others affected above and belowground biomass, roots may be key drivers during the creation of these priority effects, and interaction outcomes between plants depended on neighbour identity and location, modulated by the order they arrive in. The results suggest that priority effects can be used by sowing different species or plant functional groups at different time to steer a community to a desired trajectory depending on the restoration goal. However, there is a need to test contingency, potential, and long term impacts of such possible tools for restoration.
Für die lernförderliche Verknüpfung von Theorie und Praxis in der Lehrerbildung bieten sich insbesondere innovative Lerntools wie das Lernarrangement Videokonferenzsystem an. Selten liegt der Fokus bei der Forschung zu Theorie und Praxis allerdings auf den Überzeugungen der Lehramtsstudierenden zu Theorie und Praxis. Man weiß deswegen nur wenig darüber, was Lehramtsstudierende über diese beiden Konzepte denken. In dieser Studie wird deswegen der Frage nachgegangen, welche Überzeugungen Lehramtsstudierende zu Theorie und Praxis haben. Des Weiteren wird anhand des Lernarrangements Videokonferenzsystem untersucht, inwieweit Lehramtsstudierende Verknüpfungen von Theorie und Praxis als solche wahrnehmen und ob sich die Überzeugungen zu Theorie und Praxis nach der Arbeit mit dem Lernarrangement Videokonferenzsystem verändern können. Anhand qualitativer Leitfadeninterviews wurden 54 Lehramtsstudierende der Leuphana Universität Lüneburg zu zwei Messzeitpunkten befragt und anschließend mithilfe der qualitativen Inhaltsanalyse ausgewertet. Die Ergebnisse zeigen, dass die Studierenden theoriekonforme, unvollständige sowie der Theorie widersprechende Überzeugungen zu Theorie und Praxis haben und dass ihnen beide Konzepte wichtig sind. Allerdings wissen die Studierenden häufig nicht, wie sie Theorien nutzen können. Positiv für das Lernen der Studierenden scheint dabei zu sein, wenn diese möglichst viele unterschiedliche Praxiselemente sowie Theorie-Praxis-Verhältnisse in ihrem Studium wahrnehmen. Die Studierenden erkennen das Lernarrangement Videokonferenzsystem als eine Verknüpfung von Theorie und Praxis an. Sie nennen außerdem die grundliegenden Konzepte des Lernarrangements Videokonferenzsystem als lernförderlich. Schließlich scheinen die Überzeugungen der Studierenden zu Theorie und Praxis veränderbar zu sein. Aus den Ergebnissen der Studie lässt sich ableiten, dass eine einfache Erhöhung des Praxisbezugs in der Lehrerbildung nicht zielführend scheint. Es werden aber mehr Konzepte benötigt, die Theorie und Praxis sowie ihre unterschiedlichen Verhältnisse miteinander verbinden. Des Weiteren bedarf es im Studium mehr Kommunikation über sowie Lerngelegenheiten zu Theorie und Praxis.
Die Agenda 2030 der Vereinten Nationen und diverse daraus abgeleitete Nachhaltigkeitsstrategien setzen einen zeitlich fest definierten Rahmen bis in das Jahr 2030. Für die Umsetzung dieser Strategien sind zwei Aspekte entscheidend - ein fundiertes inhaltliches Verständnis von politischer Strategie und ein darauf aufbauendes praxistaugliches Instrument, das den politischen Strategen bei einer erfolgreichen Umsetzung und Implementierung einer Strategie unterstützt. Diese Arbeit möchte zu beiden Aspekten einen Beitrag leisten. Zum einen wird aus der Zusammenführung von Theorie und Praxis die Natur des inhaltlichen politischen Strategiebegriffs erforscht. Zum anderen wird darauf aufbauend ein praxis- und erfahrungsorientiertes Anwendungsmodell entwickelt, das typische potentielle Herausforderungen und entsprechende potentielle Handlungsoptionen je Strategieabschnitt benennt. Durch die Subsumierung von Erfahrungswissen unterstützt das Modell dabei vor allem das praktische Urteilsvermögen des politischen Strategen bei der Erreichung politikstrategischer Ziele. Um zu dem praxisrelevanten Anwendungsmodell zu gelangen ist es notwendig, sich zuvor Klarheit über die besonderen Anforderungen und Herausforderungen des speziellen politischen Strategiebegriffs zu verschaffen. Die politische Umwelt mit ihren spezifischen Mechanismen unterscheidet sich fundamental von den bisher bekannten Strategiefeldern Militär und Betriebswirtschaft. Da eine Strategie immer die konkrete Umweltsituation und die individuellen Situationsmerkmale berücksichtigen muss, ist - wie diese Arbeit zeigt - eine simple Übertragung strategischer Allgemeinplätze aus Militär und Ökonomie von vornherein zum Scheitern verurteilt.
Lehrkräfte benötigen professionelle Kompetenzen, um den spezifischen Bedürfnissen von mehrsprachigen Schülern gerecht zu werden. Gelegenheiten zum Kompetenzerwerb im Bereich sprachlicher Heterogenität sind daher unerlässlich in der Lehramtsausbildung. Um angemessene Lerngelegenheiten identifizieren und evaluieren zu können, werden in dieser Arbeit zum einen die kognitiven und motivational-affektiven Facetten professioneller Kompetenz für den Bereich Sprachliche Heterogenität modelliert. Zum anderen werden ein Testinstrument zur Messung der kognitiven Facetten (DaZKom-Test) sowie ein Fragebogen zur Erfassung motivational-affektiver Facetten vorgestellt. Die vorliegende Arbeit informiert über die Validierung der Testwertinterpretation des DaZKom-Tests, die Identifizierung von Typen bezogen auf ihre Überzeugungen zu Mehrsprachigkeit in der Schule bei angehenden Lehrkräften, und stellt ein erweitertes theoretisches Kompetenzmodell vor, welches einen internationalen Vergleich von Kompetenzen (angehender) Lehrer ermöglicht. Anhand der gewonnenen Ergebnisse dieser Arbeit ist ein besseres Verständnis der Lehramtsausbildung in Bezug auf den Umgang mit mehrsprachigen Schülern möglich.
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.
Die Öffnung der Universitäten in Deutschland für nicht-traditionelle Zielgruppen schafft neue Bildungsmöglichkeiten für Studienanwärter mit beruflichen Vorbildungen. Eine entscheidende Funktion kommt hierbei den außeruniversitär akkumulierten Berufserfahrungen zu. Diese lassen sich mittlerweile auf Studienleistungen anrechnen. Vor dieser Ausgangslage werden Berufserfahrungen als berufliches Kapital verstanden, das verstärkt von dieser neuen und nicht homogenen Gruppe zukünftiger Studierender als Zugangsmöglichkeit zur Universität genutzt wird. Zudem bieten Universitäten in wachsendem Umfang weiterbildende Studiengänge an, die den Erwerb von beruflichem Kapital synchron zum Erwerb von universitärem akademischem Kapital ermöglichen. Das Auftauchen neuer, nicht-traditioneller Studierendengruppen führt zu Veränderungen im System der Universität, auf welche die bereits etablierten Akteure in diesem Feld, insbesondere die akademischen Mitarbeitenden, reagieren müssen. Die Dissertation untersuchte mit Hilfe eines Mixed-Method-Designs habitualisierte Verhaltens-, Denk- und Wahrnehmungsmuster von akademischen Hochschulmitarbeitenden im Hinblick auf Studierende mit beruflichem Kapital. Es wurde zum einen eine quantitative Befragung von akademischen Mitarbeitenden an einer Universität und zum anderen eine explorative qualitative Interviewstudie über akademische Hochschullehrende an insgesamt sechs deutschen Universitäten durchgeführt. Die Universitäten und Fächer in beiden Studien unterschieden sich in dem Grad, in dem die Hochschulöffnung bereits vorangeschritten war. In beiden Studien wurden geschlechtsbezogene, fachspezifische und organisationale Unterschiede analysiert, die Rückschlüsse auf den Habitus der Hochschulmitarbeitenden und deren Blick auf die (angehenden) Studierenden mit beruflichem Kapital ermöglichen. Die Analyse konnte in beiden Studien aufzeigen, dass akademische Hochschulmitarbeitende mehrheitlich Einstellungen geäußert haben, die zwischen Ambivalenz und einer ausgesprochen inklusiven Haltung gegenüber der Hochschulöffnung zu verorten sind. Durch die quantitative Studie ließ sich ermitteln, dass weibliche Befragte und Angehörige der sogenannten weichen Wissenschaften, hinsichtlich der Hochschulöffnung solche Positionen einnahmen, die durch ein hohes bzw. ein Höchstmaß an Inklusion gekennzeichnet sind. Die Auswertung der qualitativen Analyse konnte zeigen, dass Befragte, die ihrerseits offen auf die neuen Studierendengruppen zugehen, überwiegend auch eine konstruktivistische Lehr-Lern-Überzeugung haben und eine verstärkte Anwendungsorientierung in der Lehre praktizieren, organisationale Faktoren hatten hingegen einen vernachlässigbaren Einfluss auf die Einstellungen und den Habitus der untersuchten Wissenschaftler.
Poor quality of freshwaters is a widespread problem. The concept of complexity is a particularly promising concept to analyse and address this problem, and public policy problems more generally. The main reason is the concept's strength in unifying structural features of problems within a more comprehensive structural approach to political problem-solving. So far, however, these possible benefits remained hidden given the lack of a clear understanding of complexity, ultimately hampering a systematic analysis of the implications of complexity for solutions and governance strategies. This study aims at strengthening the value of the concept of complexity for systematic comparative analyses of water-related problems and public policies in general. To achieve this goal, this work is to specify the concept of complexity as well as the implications of complexity for solutions and governance strategies, both from a theoretical and an empirical point of view. To this end, five main basic approaches are applied, referring to underlying premises, the role of an interdisciplinary approach, the European Water Framework as an empirical reference point, the integration of practical knowledge, and the focus on external validity. This dissertation provides a detailed operationalisation of complexity related to the dimensions of goals, variables, dynamics, interconnections, and informational uncertainty. It also shows that freshwater pollution-related problems in Germany differ along these five complexity dimensions. This applies to 37 types of pollution-related problems and four clusters of problems, which refer here to tame, wicked, system complexity, and uncertainty problems. This dissertation suggests that relations between complexity and policy delivery can be both positive and negative and vary along dimensions of complexity and policy delivery. Regarding the analysed freshwater pollution problems, this work also shows various effects of complexity on policy delivery, both along the 37 types of problems, and along four clusters of wicked problems. This dissertation suggests a differentiated theoretical approach to define governance for complex problem-solving, demonstrating that the role of diverse institutions, actors, and interactions differs for solutions along five key dimensions of complexity and different management strategies that are information gathering, modelling, using decision-support tools, prioritising of measures, conflict solving, deciding under uncertainty, and being adaptive and flexible.
This thesis deals with the influence of sustainability communication on the purchase decision of sustainable tourism products involving German specialist tour operators. Sustainability communication is a challenge, because sustainable tourism is an abstract and vague concept which consumers find it difficult to grasp and about which they are sceptical. The service characteristics of tourism products complicate the decision making stage, which is a high-involvement situation of uncertainty to which sustainable product attributes add complexity. As an introduction, an interdisciplinary theory discussion reveals knowledge gaps in terms of the value-belief-norm theory and the elaboration likelihood model (ELM). The first article, which is the first systematic literature review on the topic, reveals that there is a limited theoretical understanding of sustainability communication, a lack of practical understanding of how to design sustainability messages, and an inadequate set of methodologies for its research. It identifies knowledge gaps concerning: the holistic approach to sustainability communication; its role in the attitude-behaviour gap; an interdisciplinary theoretical understanding focusing on belief-based social psychological theories and theories of persuasion; qualitative methods; and experimental design. The second article investigates the role of sustainability communication in the attitude-behaviour gap, employing the value-belief-norm theory to explain how information is processed by special interest customers. Interview findings show that ineffective sustainability communication is the reason for the gap and that customers unintentionally booked sustainably. The study identifies eight groups of beliefs which explain the processing of sustainability attributes. Sustainability information is effective when it is value-congruent, that is, when customers perceive they can make a difference, they begin to ascribe a responsibility to themselves. The third article investigates how to design an effective sustainability message in tour operator advertising. Drawing on the ELM, the study shows that appeal type does not significantly influence persuasion but the topic presented is important. Cultural sustainability is the sustainability topic that is most persuasive for cultural tourists, while consumer prior knowledge and issue-involvement with the topic promote successful information processing.
Space-related science and technologies affect our daily life. Many countries have already formulated national space regulations to regulate their space activities. China, as one space-faring country, has obtained several achievements in space science and technologies. In recent years, Chinese private space companies have sprung up quickly, which requires a stable and foreseeable legal framework to ensure development. However, compared to the other space powers, China is the only one that has not enacted any formal national space laws. Against the background of strengthening the rule of law in China, research on China's domestic space legislation is valuable and significant. The purpose of this thesis is two-fold. First, to find the legal basis and necessity of national space legislation and to extract the basic content of the existing national space legislation, simultaneously, to identify the new developments in the content of other States´ legislative practices. Second, based on the study of national space legislation, to propose the essential content of China's space legislation.
This cumulative thesis extends the econometric literature on testing for cointegration in nonstationary panel data with cross-sectional dependence. Its self-contained chapters consist of two publications and two publication manuscripts which present three new panel tests for the cointegrating rank and an empirical study of the exchange rate pass-through to import prices in Europe. The first chapter introduces a new cointegrating rank test for panel data where the dependence is assumed to be driven by unobserved common factors. The common factors are first estimated and subtracted from the observations. Then an existing likelihood-ratio panel cointegration test is applied to the defactored data. The distribution of the test statistic, computed from defactored data, is shown to be asymptotically equivalent to that of a test statistic computed from cross-sectionally independent data. The second chapter proposes a new panel cointegrating rank test based on a multiple testing procedure, which is robust to positive dependence between the individual units' test statistics. The assumption of a certain type of positive dependence is shown by simulations not to be violated in panels with dependence structures commonly assumed in practice. The new test is applied to find empirical support of the monetary exchange rate model in a panel of eight OECD countries. The third chapter puts forward a new panel cointegration test allowing for both cross-sectional dependence and structural breaks. It employs known individual likelihood-ratio test statistics accounting for breaks in the deterministic trend and combines their p-values by a novel modification of the Inverse Normal method. The average correlation between the probits is inferred from the average cross-sectional correlation between the residuals of the individual VAR models in first differences. The fourth chapter studies the exchange rate pass-through to import prices in a panel of nineteen European countries through the prism of panel cointegration. Empirical evidence supporting a theoretical long-run equilibrium relationship between the model's variables is found by the newly proposed panel cointegration tests. Two different panel regression models, which take both cointegration and cross-sectional dependence into account, provide most recent estimates of the exchange rate pass-through elasticities.
Mit der Vergabe- und Vertragsordnung für Bauleistungen (VOB) des Deutschen Vergabe- und Vertragsausschusses (DVA) für Bauleistungen existiert ein verbindliches dreiteiliges Regelwerk, welches allen Bauverträgen zugrunde gelegt werden kann. Teil B beinhaltet die Allgemeinen Vertragsbedingungen für die Ausführung von Bauleistungen und definiert die Abwicklung der beauftragten Leistungen. Auf Grund des hohen Konfliktpotenzials kommt es dabei nicht selten zu Gerichtsverfahren mit hohen Kosten und Risiken. Diese Streitigkeiten behandelt inhaltlich der § 18 VOB/B. Gemäß § 18 Abs. 2 VOB/B wird ein außergerichtliches Verfahren im Umgang mit Meinungsverschiedenheiten beschrieben. Kostenaufwendige Gerichtsprozesse können durch die Inanspruchnahme der Verfahrensarten gem. § 18 VOB/B vermieden werden. Speziell das Verfahren gem. § 18 Abs. 2 VOB/B beschreibt ein Schlichtungsverfahren, welches sich im Vergleich zu gerichtlichen Auseinandersetzungen durch seine Kostenneutralität und verhältnismäßig kurze Verfahrensdauer auszeichnet. Mit der vorliegenden Arbeit wird herausgearbeitet, welche Maßnahmen ergriffen werden müssen, um dieses Verfahren zu stärken. Dazu werden als Erstes die Grundlagen des Bauvertrags dargelegt. Das zweite Kapitel befasst sich umfänglich mit Konfliktursachen und ihre Auswirkungen in Bauvorhaben. Im dritten Kapitel werden die Verfahrensarten nach § 18 VOB/B als Streitbeilegungsinstrumente des öffentlichen Auftraggebers detailliert vorgestellt und im vierten Kapitel die praxisbezogene Anwendung des Verfahrens nach § 18 Abs.2 VOB/B beleuchtet. Die Darstellung der Praxiserfahrungen sowohl der Auftraggeber als auch der Auftragnehmer führt zu den Schwächen und Stärken des Verfahrens. Im fünften Kapitel folgt die Betrachtung der Wiederstände, die eine Weiterentwicklung des Verfahrens entgegenstehen und gleichzeitig werden die Maßnahmen zur Stärkung der Akzeptanz des Verfahrens aufgezeigt.
The dissertation analyzes the role of large banks in the context of financial (in)stability. Based on the underlying "too big to fail"-problem (TBTF), the three included papers investigate the reasons for the instability of banking systems on a national and international level. Already in advance, but at least since the years 2007/2008 with the escalation of the financial crisis, especially large banks are under critical supervision of regulators and the society. There exist numerous aspects that should to be taken into account when addressing TBTF which complicates the finding of a solution to the problem. In particular, the thesis investigates three major issues in this context: (1) The contribution of the size of a bank to the development of financial crises or the exposure of large banks to systematic risk and contagious spillovers. (2) The spillover effects from one banking system to another and the importance of banks' foreign asset holdings for the transmission of sovereign risk on foreign banks. (3) The impact of the degree of competition in the German banking market on the stability of the banking system.
Whereas the extant literature discusses what Sustainability-Oriented Innovations (SOIs) are and why firms develop them, little is known about how they are developed. To enable firms to innovate for sustainability, it is essential to know more about the processes underlying SOI development, which are considered as very difficult, with many firms failing. Drawing on several academic papers and relying on qualitative research methods, the thesis uses the Fireworks model to examine how innovation processes unfold at established small and medium-sized enterprises (SMEs). The main contribution of the thesis is to advance the Fireworks model to the context of SOIs unfolding at SMEs. The findings reveal that SOIs unfold in an emergent, somewhat chaotic way, that duration and outcome are uncertain, that the overall journey is composed of multiple intertwined innovation paths, of which several will likely lead to setbacks. To manage this complex process, the thesis suggests to set four management foci: (1) to create a dedicated organizational unit for exploration, (2) to create conditions allowing intelligent learning for efficient exploration, (3) to carry out in-depth investigation of the related technological innovation systems, and (4) to plan carefully the re-integration of the innovation into the core business for commercialization.
The timber shortage led to large scale afforestations on previously agriculturally used land in Central Europe during the 19th and 20th century. Widespread afforestation programs created recent forest ecosystems (i.e. young forest systems in terms of their development history). Despite the positive effect of increasing the forest area of Central Europe, the ecological effects of these land-use changes on forest ecosystems remain poorly understood. In order to increase the understanding of ecosystem processes in forests, an assessment of conceivable shifts in ecosystem functions caused by former land-use changes and forest management is required. By analysing aboveground growth rates of European beech (Fagus sylvatica L.) in response to environmental change drivers, such as climate extremes and nitrogen (N) deposition, the presented thesis aims to assess the role of land-use and management legacies in modulating present responses to drivers of environmental change. To this end, annual radial growth rates of individual trees were measured in mature beech stands. The investigated stands differed either in their land-use history (i.e. ancient forest sites versus recent forests) or their forest management history (i.e. managed forest sites versus short-term and long-term unmanaged forest sites). Measurements of radial growth rates were complemented by analyses of the fine root systems, soil chemical properties and crown projection areas to gain insights into the mechanisms underlying alterations in tree growth. Within the projects of the presented thesis, shifts in the climate-growth relationships driven by land-use and management legacies were analysed. In addition, land-use legacy mediated differences in the climate-nitrogen-growth relationships were assessed. The key findings are: (I) Soil legacy driven alterations in the fine root systems cause a higher sensitivity of radial increment rates to water deficits in summer for trees growing on recent forest sites than for trees growing on ancient forest sites. (II) Management legacies (in terms of tree release) enhance the sensitivity of beech’s radial growth to water deficits in spring through changes in crown sizes. (III) Interacting effects of spring water deficits and co-occurring high deposition of reactive N compounds lead to stronger radial growth declines in trees growing in ancient forests. This is likely caused by resource allocation processes towards seed production, which is, in turn, mirrored by decreasing radial growth rates. In this context, high N deposition likely boosts mass fructification in beech trees. Overall, it has been demonstrated that the ecological continuity plays a crucial role in modulating both climate sensitivity and the growth response to interacting effects of water deficits and nitrogen deposition in beech trees. The presented thesis identified a trade-off between the climate sensitivity and maximised growth rates within beech trees, depending on forest history. The results show that the growth of beech in ancient, unmanaged beech forests is less sensitive to water deficits than in recent and managed beech forests. Additionally, interacting effects of spring water deficits and N deposition likely increase the reproductive effort of beech trees, particularly in ancient forests. Thus, the results of this thesis once again underpin the uniqueness of ancient, unmanaged beech forests, whose importance for the conservation of biodiversity has been widely acknowledged. In summary, the presented thesis highlights the need to consider the "ecological memory" of forest ecosystems when predicting responses to current and future environmental changes.
Metals fulfill crucial functions in areas as diverse as renewable energy, digitization and life style appliances, mobility, communication, or medicine. In the context of sustainability, achieving a more sustainable metal use means (i) minimizing the adverse effects associated with metal production and use and (ii) sustaining the availability of metals in a way that benefits present and future generations. Urgent need to act to avoid bottlenecks as well as meeting the challenge of possible conflicts of use among those areas of application calls for appropriate strategy making to intervene in the complex field of metal production and use that involves various, often interlinked operating levels, actors, and spatial and temporal scales. This dissertation focuses on strategies as a means to intervene in a system. It pursues the question, which design features could guide future strategy making to foster sustainability along the whole metal life cycle, and especially, how a better understanding of temporalities, i.e. understanding time in a diverse sense, could improve strategy design and help to bridge the assumed "transformation-material gap". This research converges the results from four research studies. A conceptual part explores the role of temporalities for interventions in complex and interlinked systems, which adds to the conceptual basis, on which the empirical part builds up to explore present and future interventions in metal production and use. The research revealed three essential needs that future strategies must tackle: (i) managing the complex interlinkages of processes and activities on various operational levels and spatial and temporal scales, (ii) providing clear guidance concerning the operationalization of sustainability principles, and (iii) keeping activities within the planet’s carrying capacity and embracing constant change as an inherent system characteristic. In response to these needs, the author developed three guidelines with two design features each (one relating to content, and one to the process of formulating and implementing the strategy) to guide future strategy making. The results show that time matters in this respect. If considered in close relation to space and diversely understood in the sense of temporalities, it serves to (i) understand the impact (duration and magnitude) of an intervention, (ii) recognize patterns of change that go beyond establishing linear, one-dimensional connections, and (iii) design interventions in a way that considers the resilience of a system. These findings can contribute to closer considering our understanding of transformation processes towards sustainability in future interventions in metal production and use.
This cumulative dissertation deals with the association between corporate governance, corporate finance and corporate tax avoidance in four scientific articles. The aim of this dissertation is to explain corporate tax avoidance by (a) focusing on corporate governance institutions as determinants of tax avoidance and (b) focusing on financial consequences of tax avoidance. Due to the close association between corporate governance and the concept of corporate social responsibility (CSR), the relationship between CSR and tax avoidance is also addressed. The first article using structured literature review methodology, analyzes extant research on the association between corporate governance and tax avoidance based on stakeholder-agency theory. However, also classical principal-agent theory is taken into account as its classical foundation. The first article identifies a number of open research questions and thereby serves as a theoretical basis for the subsequent articles. The second article also using structured literature review methodology, analyzes extant research on the association between CSR and tax avoidance. This article is also based on stakeholder-agency theory and identifies open research questions. The third article based on results of the first article, investigates tax avoidance by German private family firms as a specific variant of corporate governance, using an empirical quantitative approach. The article finds that (a) German private family firms avoid more tax than non-family firms, that (b) tax avoidance is positively associated with the capital stake of the family and that (c) tax avoidance is positively associated with the number of shareholders in both family and non-family firms. Results reinforce that corporate tax avoidance is associated to conflicts among the shareholders of private firms. The fourth article investigates the cost of debt of German public firms as a function of tax avoidance and tax risk. The article finds that (a) tax avoidance is negatively associated to the cost of debt, that (b) tax risk is positively associated to the cost of debt and that (c) the association between tax avoidance and the cost of debt becomes negative when a high level of tax risk is present.
Wissen äußert sich in der Fähigkeit, Sachverhalte wahrheitsgetreu zu beschreiben, ihre Ursachen zu erkennen und zu erklären. Grundlage einer angewandten Wissenschaft der Unternehmensführung ist Wissen über das Verhalten von Unternehmen. Die Entscheidungsforschung ist als Versuch zu verstehen, solches Wissen zu schaffen. Sie nimmt dabei eine sehr spezielle Perspektive ein, die sie von anderen unternehmenstheoretischen Ansätzen unterscheidet, d.h. andere wissenschaftliche Ansätze beabsichtigen zwar ebenfalls die Erklärung des Unternehmensverhaltens, sie wählen aber einen anderen Ausgangspunkt. Der vorliegende Aufsatz geht auf einige ausgewählte Studien ein, die dazu dienen können, das Anliegen der entscheidungsorientierten Betrachtungsweise an einer ausgewählten Fragestellung zu verdeutlichen. Er soll außerdem zeigen, wie die Erkenntnisse der Entscheidungsforschung dazu beitragen können, die Unternehmensführung zu verbessern. Zu diesem Zweck wird das deskriptive dem normativen Vorgehen gegenübergestellt.
Die vorliegende Studie versucht, einige Aspekte der „Qualität“ strategischen Handelns in KMU zu beleuchten. Im Einzelnen geht es um die folgenden Teilfragen: Welche inhaltlichen Strategien verfolgen KMU? Welche strategischen Orientierungen („Handlungsdispositionen“)lenken das Handeln von KMU? Entspricht das Zustandekommen strategischer Entscheidungen den Anforderungen an einen
Abstract Es ist ein verbreitetes Vorurteil, dass kleinere Unternehmen weniger gut geführt werden als größere Unternehmen. Empirische Unterstützung erfährt diese Auffassung durch Erhebungen, die zeigen, dass kleinere Unternehmen das vorhandene betriebswirtschaftliche Instrumentarium nicht in gleichem Umfang nutzen wie größere Unternehmen. Der vorliegende Beitrag zeigt, dass dieser Tatbestand nichts über die Qualität der Unternehmensführung aussagt. Die Unternehmensgröße schafft zwar unterschiedliche Handlungsvoraussetzungen. Die Fähigkeit effiziente Handlungsstrukturen zu entwickeln bleibt davon jedoch unberührt.
Abstract As simple as it is, results describing the world are heavily dependent on the quality of the underlying data. One of the very crucial variables in microanalytical analyses of well-being and human resources is income. The more, when the situation of the self-employed is regarded. This paper focus on the distribution of income based on very sound data: the German Income Tax Statistic (Einkommensteuerstatistik) 1992. New is the actual possibility to use for the first time such a sound microdatabase to analyze the self-employed in particular: a 100.000 microdata sample of the population wide German Income Tax Statistic. New is the comparison between income from dependent and self-employed work with emphasis on the entrepreneurs and professions, and new is the indepth decomposition inequality analysis of the aggregated groups and of the single professions based on an inequality generalized entropy decomposition approach. One overall striking result is: the occupational status as an employee, entrepreneur or as a profession with its connected low between inequality share is by far not the overall driving factor to ‘explain’ the overall income distribution and inequality picture of the re-unified Germany; it is the within group inequality which counts in particular.
To improve the properties of thermochemical heat storage materials, salt mixtures were evaluated for their heat storage capacity and cycle stability as part of the innovation incubator project "Thermochemical battery" of the Leuphana university Lüneburg. Based on naturally occurring compound minerals, 16 sulfates, 18 chlorides and 5 chloride multi-mixtures, 18 bromides and 5 intermixtures between sulfates, chlorides and bromides were synthesized either from liquid solution or by dry mixing for TGA/DSC screening before continuing the heat storage evaluation with five different measurement setups at a laboratory scale. The TGA/DSC analysis served as a screening process to reduce the number of testing materials for the upscaled experiments. The evaluation process consisted of a three-cycle dehydration/hydration measurement at Tmax=100°C and Tmax=200°C. In case of the bromide samples a measurement of hydration conditions with Tmax=110°C and a water flow at e=18.68mbar, were added to the procedure to detect the maximum water uptake temperature. Also, a single dehydration to a temperature of Tmax=500°C was implemented to observe melting behavior and to easier calculate the samples’ stages of hydration from the remaining anhydrous mass. Materials which showed high energy storage density and improved cycle stability during this first evaluation were cleared for multi-cycle measurements of 10 to 25 dehydration and hydration cycles at Tmax = 100 to 120°C and the evaluations at m=20 to 100g scale. An estimate for the specific heat capacities at different temperatures of the materials which passed the initial stage was calculated from the TGA/DSC results as well. The laboratory scale measurement setup went through five stages of refining, which led to reducing the intended maximum sample mass from m=100g to m=20g. A switch from supplied liquid water to water vapor as the used reactant was also implemented in exchange for improved dehydration conditions. Introducing a vacuum pump for evaporating the water limited the influence of outside heat sources during hydration and in-situ dehydration was enabled as to not disturb the state the samples were settling in between measurements. Baseline calculation from blanc measurements with glass powder and attempts to calculate the specific heat capacity cp of the tested materials by 6 applying the Joule-Lenz-law to the measurement apparatus was another step of method development. The evaluation process of the laboratory scale tests at the final setting consisted of 1 to 5 cycle measurements of in-situ dehydration and hydrations with applied vacuum for t=30 minutes at p~30mbar. Upscaling the sample mass to m=20g allowed for a close observation of different material behaviors. Agglomeration, melting and dissolving of the m=10mg samples during the TGA/DSC analysis can be deducted from the recorded measurement curves and the state of the sample after measurement. However, at laboratory scale the visible volume changes, observed sample consistency after agglomeration and an automatic removal of molten and dissolved sample mass during the measurement allowed for a better characterization and understanding of the magnitude of the actual changes. This was done for the first time, particularly for mixed salts. Of the original number of 62 samples, 4 mixtures which passed the initial TGA/DSC screening namely {2MgCl2+ KCl}, {2MgCl2+CaCl2}, {5SrBr2+8CaCl2} and {2ZnCl2 + CaCl2} were chosen for further evaluation. The multi-cycle TGA/DSC measurements of {2MgCl2+ KCl}, {2MgCl2+CaCl2} and {5SrBr2+8CaCl2} showed an improved cycle stability for all three materials over the untreated educts. Of the four materials {2ZnCl2 + CaCl2} displayed the strongest deliquescence during hydration in the upscaled experimental setup. {2MgCl2+CaCl2} proved to be the most stable material regarding the heat storage density. The {MgCl2} content of the mixture is likely to partially or completely react to {Mg(OH)Cl} at temperatures of T>110°C, which however does not impede the heat storage density. {5SrBr2+8CaCl2} displayed a low melting point in hydrated state, causing a fast material loss. This makes it an undesirable storage material. A lower heating rate may still help to avoid an early melting. The {2MgCl2+KCl} mixture was the most temperature stable of the mixtures showing no melting or dissolving behavior. A reaction of the {MgCl2} component of the mixture to {Mg(OH)Cl} was not observed within the applied temperature range of T=25 to 200°C.
Many fewer women than men try the entrepreneurial way in Germany. Any explanation for this phenomenon must be complex, as many factors are relevant for its production. Among other things, it is possible to speculate on sexual/gender discrimination, on more or less voluntary decisions of women or on different starting conditions for potential entrepreneurs. We assume that these options are closely related. This paper will concentrate, though, on the third alternative. Its focus will be set on the “family field,” or more precisely, on the role of family law in hindering women from trying self-employment. The family field in Germany has not evolved in the sense of gender equality along with all other areas of society - e.g., entrepreneurship. No gender equality is possible if the family field is not part of it. This paper analyses causes and consequences for this phenomenon.
Key Words: Gender studies, Family Law, Entrepreneurship, chance equality, social sustainability
Umsonstläden und couchsurfing sind Beispiele neuer Nutzungsformen
Der massive Ausbau der Photovoltaik (PV) stellt das deutsche Stromversorgungssystem vor Herausforderungen. Es gilt, die Stromerzeugung aus PV dem Bedarf anzupassen, Netzüberlastungen durch Solarstrom zu verhindern und den Strom in den Markt zu integrieren. Diese Arbeit untersucht, inwiefern dezentrale Stromspeicher als Lö-sungsansatz zur Bewältigung dieser Herausforderungen geeignet sind und inwieweit der derzeitige Rechtsrah-men diesen Ansatz fördert. Es zeigt sich, dass dezentrale Speicher einen Beitrag zur System- und Marktintegrati-on der PV leisten könnten, die rechtliche Förderung aber unzureichend ist, um dieses Potential auszuschöpfen.
In dieser Arbeit wird das Thema der Suffizienz als Aspekt der Frage nach dem guten Leben betrachtet. Der Rekurs auf das gute Leben ermöglicht den Rückgriff auf die Konzeptionen des guten Lebens von Epikur und der Stoa. Diese Konzeptionen werden hinsichtlich ihrer Suffizienz untersucht und es wird der Frage nachgegangen, ob sich durch deren Aktualisierung individualethische Zugänge zu Suffizienz ergeben. Ergebnis der Arbeit ist, dass die von den Philosophen vorgeschlagenen Lebensweisen suffizient sind und sich unter verschiedenen Anknüpfungspunkten an heutige gesellschaftliche Probleme aktualisieren lassen. Über die in den Konzeptionen thematisierten Zielen des lustvollen Lebens (Epikur) und der Selbstmächtigkeit (Stoa) ergeben sich individualethische Zugänge zu Suffizienz. Diese benötigen nicht den Rückgriff auf das Konzept der Nachhaltigkeit.
Personally meaningful tourist experiences foster subjective mental wellbeing. Modern, human-centred technologies such as gamified technology have been recognised as a promising means to support tourists in their co-creation of meaningful tourist experiences. However, a deeper understanding and conceptualisation of tourists' engagement with gamified technologies in the tourist experience has remained absent so far. This study draws on positive psychology as the guiding theoretical lens to conceptualise and explore tourists' underlying motives for engaging with gamified technology, as well as the gratifications thereof for the tourist experience. In doing so, this thesis identifies how tourists generate meaning through interacting with gamified technology in the tourist experience, thereby fostering the co-creation of meaningful tourist experiences and contributing to subjective mental wellbeing. Being among the first studies to link the concepts of positive psychology, gamified technology, and tourist experiences, the results of this thesis provide rich findings on the underlying motives for tourists to engage with gamified technology during vacation, as well as the gratifications of gamified technology for the creation of meaning in the tourist experience. Using the theoretical lens of positive psychology and achievement motivation theory as the main theoretical underpinning, this study is positioned at the intersection of social psychology, human-computer interaction, and tourism as the field of application. Conceptually, this thesis provides an in-depth understanding of tourists’ engagement with gamified technology, including the socio-psychological motivators for engagement and the outcomes thereof for the tourist experience.
This thesis analyses how European merger control law is applied to the energy sector and to which extent its application may facilitate the liberalisation of the electricity, natural gas and petroleum industries so that only these concentrations will be cleared that honour the principles of the liberalisation directives. After having discussed the complex micro- and macro-economic considerations which accompany any concentration of business activities, this thesis discusses the merger control regime of the European Community (EC) so as to establish whether the merger control under either Art. 66 Treaty Establishing the European Coal and Steal Community (ECSCT), the case law under Art. 101 and 102 Treaty on the functioning of the European Union (TFEU) and (Art. 81 and Art. 82 Treaty Establishing the European Economic Community (ECT), as it was introduced by the Commission and reviewed by the CJEU, the original Merger Regulation (MR1989) or the amended Merger Regulation of 1997 (MR1997) or the amended Merger Regulation of 2004 (MR2004) facilitate the liberalisation of European electricity and gas markets. Said liberalisation was introduced by the Internal Electricity Market Directive (IEMD), the Hydrocarbons Licensing Directive and the Internal Gas Market Directive (IGMD). The paper focuses on the contestable idea that regulatory amendments - especially the introduction of third party access by means of the directives - only form a first necessary condition for attaining economic alterations whereas pro-active conduct of the marketers is the second and decisive one in order to increase the competitive performance of the European energy supply industries. The analysis is supported by a second argument which relates closely to the ambivalent nature of concentrations: A concentration may be used to increase the process of market opening and the expansion into new markets by pooling of scarce resources. It may also be used as a retro -active means so as to create national champions, increase barriers to market entry of new competitors, enable cross-subsidisation so as to expand dominant positions on heretofore competitive up- and downstream markets.
This dissertation includes six articles tied together by the overarching question of how changes in public opinion, economics and public policy co-evolve in mature democracies, with a focus on redistributive (in seven European democracies) and secessionist preferences (in Catalonia and Scotland). The theoretical inspiration derives from three sources: 1. the Macro Polity model by Erikson, MacKuen/Stimson, 2. the Thermostatic Responsiveness model by Soroka and Wlezien, and 3. the literature on representation gap models by Gilens, Elsaesser and others. The Macro Polity and Thermostatic Responsiveness models come with an optimistic undertone, emphasizing that public policies adapt to public opinion, producing the policy-opinion congruence that defines responsive government. The Representation Gap model, by contrast, is more pessimistic in highlighting that the preferences of low-income groups are generally worse represented in public policies than the preferences of middle-income and especially high-income groups. While there is evidence in favor of these models for the majoritarian political systems in the US, Canada and the UK, less is known about the validity of these models in proportional democracies of continental Europe. The contributions in this dissertation address this research gap by integrating the three models and combining nearly 500 surveys to study the evolution of European public opinion at the national and subnational level.
Uganda has been plagued by political instability in the past and wide spread abuse of human rights coupled with failed economic policies. However, the country has witnessed increased economic growth and the government has embarked on several poverty eradication programmes despite rising income inequalities and poverty in the country. The task of ensuring poverty as a human right in the country has not been an easy one for those charged with the duty of ensuring the right to freedom from poverty. This research examines the complexity of attaining the right to freedom from poverty in a country like Uganda. This study will also give a philosophical view on poverty and human rights and those responsible for ensuring the implementation of this right. Through the analysis, the research examined the key challenges faced in attaining the right to freedom from poverty in Uganda, discussed how poverty was defined through different perspectives. The information provided in the analysis is further examined by putting the theoretical findings in correspondence with the gathered empirical information for more definitive results of the study. The fundamental results and conclusion of this research revealed the overall challenges faced in regarding poverty as a human right which include how poverty is defined, the mindset, the political history of Uganda and so on. However, the study has recommended extensive research into the role of the family in ensuring poverty as a human right and further research in the effectiveness of the laws in Uganda in ensuring poverty as a human right.
Since the early 2000s, ecosystem services strongly gained significance as a research topic. However, the temporal dimension of ecosystem services has not been taken into consideration, although this should be the basis for a sustainable long-term management of ecosystems and their services. Therefore, the author presents three articles in this thesis that deal with temporal aspects of ecosystem services. In two of them she also present a proposal for a framework for the classification of ecosystem services based on their temporal dynamics. In this dissertation she differentiates between two types of temporal aspects, both of which have in common that change takes place over a certain period of time. The concepts of transformation, transition and regime shift are used to describe changes in social or ecological systems as a whole, for example the transformation towards a more sustainable society. The temporal dynamics, on the other hand, relate to the temporal changes in ecosystem services themselves. The first article focuses on how the literature on ecosystem services incorporates social and ecological change. The second and third articles deal with the temporal dynamics of ecosystem services. While the second article presents a preliminary framework for categorizing the temporal dynamics of ecosystem services, the third article uses this framework to test how the temporal dynamics of ecosystem services are represented in the literature. Based on the insights from the three articles, the author concludes that most of the studies on ecosystem services only focus on one point in time. One reason for this is that most studies are conducted over a maximum of a four-year time span which does not allow to monitor dynamics over longer time spans.
Mental health is an important factor in an individuals' life. Online-based interventions have been developed for the treatment of various mental disorders. During these interventions, a large amount of patient-specific data is gathered that can be utilized to increase treatment outcomes by informing decision-making processes of psychotherapists, experts in the field, and patients. The articles included in this dissertation focus on the analysis of such data collected in digital psychological treatments by using machine learning approaches. This dissertation utilizes various machine learning methods such as Bayesian models, regularization techniques, or decision trees to predict different psychological factors, such as mood or self-esteem, dropout of patients, or treatment outcomes and costs. These models are evaluated using a variety of performance metrics, for example, receiver operating characteristics curve, root mean square error, or specialized performance metrics for Bayesian inference. These types of analyses can support decision- making for psychologists and patients, which can, in turn, lead to better recommendations and subsequently to increased outcomes for patients and simultaneously more insight about the interplay between psychological factors. The analysis of user journey data has not yet been fully examined in the field of psychological research. A process for this endeavor is developed and a technical implementation is provided for the research community. The application of machine learning in this context is still in its infancy. Thus, another contribution is the exploration and application of machine learning techniques for the revelation of correlations between psychological factors or characteristics and treatment outcomes as well as their prediction. Additionally, economic factors are predicted to develop a process for treatment type recommendations. This approach can be utilized for finding the optimal treatment type for patients on an individual level considering predicted treatment outcomes and costs. By evaluating the predictive accuracy of multiple machine learning techniques based on various performance metrics, the importance of considering heterogeneity among patients' behavior and affect is highlighted in some articles. Furthermore, the potential of machine learning-based decision support systems in clinical practice has been examined from a psychotherapists' point of view.
This dissertation investigates interpersonal competence development in project-based sustainability courses. Visions of a sustainable, safe, and just future cannot be reached by one individual alone. Thus, future change agents need to be able to collaborate and engage with stakeholders, to approach the manifold crises, challenges, problems, and conflicts we are facing together, and to promote and push forward sustainability transitions and transformations. Therefore, this research investigates three project-based sustainability graduate courses by comparing and contrasting teaching and learning outcomes, processes, and environments. A comparative case study approach using a Grounded Theory-inspired research design which triangulates several qualitative methods and perspectives is applied to allow for generalizable insights. Thereby, this dissertation provides empirically-informed insights which are further discussed in relation to selected teaching and learning theories. This leads, first, to a discussion of practical implications within (and beyond) sustainability higher education; and second, provides a theoretical foundation for interpersonal competence development in project-based learning settings – so that educating future change agents can gain momentum. Findings of this research show that embracing conflicts when they occur (i.e. before they provoke cascading effects in the form of further conflicts down-the-road) is an effective strategy to help further develop interpersonal competence. This requires a conflict-embracing attitude. Attitude, in general, seems to be key in interpersonal competence and competence development overall. Self-reflection, if not explicitly required by outside influences (such as instructors), arises naturally from a self-reflective attitude, and is shown to provide the basis for developing interpersonal competence. This research introduces the term "Refl-Action" which stresses the importance of pairing "learning by doing" (as is often the focus in project-based learning settings) with conscious moments of "reflecting about the doing". More specifically, the research presented here identified four learning processes for interpersonal competence development: receiving input, experiencing, reflecting, and experimenting. Based on the empirical data, when the four processes are purposefully combined, following a meaningful sequence attitudes, knowledge, and skills in collaborative teamwork and impactful stakeholder engagement, are fostered (two facets of interpersonal competence). Each of the four learning processes is set in motion through various interactions students engage in during project-based sustainability courses: student-student (labeled "peer"), student-instructor (labeled "deliberate"), student-stakeholder (labeled "professional"), and student-mentor (labeled "supportive") interactions. When these interactions are made explicit subjects of inquiry - i.e. the (inter-)action is linked with (self-)reflection – different learning processes complement one another: Interpersonal competence facets (collaborative teamwork and impactful stakeholder engagement) and domains (attitudes, knowledge, skills) are fostered. While, overall, interactions, processes, and conflicts have been identified as supportive for interpersonal competence development, trust has emerged as another variable inviting further investigation.
The dissertation consists of three scientific papers and a synopsis. The synopsis addresses the relevance of the dissertation and lists the key factors for the sustainability transition in the electricity system as a common denominator of the three papers. The relevance of the dissertation results, on the one hand, from the urgency of the sustainability transition in the electricity system and an insufficient transition willingness of the eastern European Member States. On the other hand, the Multi-Level-Perspective as one of the most important scientific frameworks to grasp transitions does not provide a sufficient explanation of its mechanisms. Moreover, Demand Response aggregators as new enterprises on the European electricity market and potential reform initiators are still under researched. The following key factors for the sustainability transition of the electricity system have been identified: supply security concerns, Europeanisation, policy making and the dominance of short-term oriented economic evaluation. Paper#1 sheds light on the roots of this problem in the context of Poland. It suggests that unfavorable regulation is symptomatic of the real, underlying barriers. In Poland, these barriers are coal dependence and political influence on energy enterprises. As main drivers, supply security concerns, EU regulatory pressure, and a positive cost-benefit profile of DR in comparison to alternatives, are revealed. A conceptual model of DR uptake in electricity systems is proposed. Applying a social mechanisms approach to the Multi-Level Perspective, paper#2 conceptualizes mechanisms of socio-technical transitions and of gaining legitimacy for transitions as co-evolutionary drivers and outcomes. Situational, action-formational, and transformational mechanisms that operate as drivers of change in a socio-technical transition require corresponding framing and framing contests to achieve legitimacy for that transition. The study illustrates the conceptual insight with the case of the coal dependent Polish electricity system. Paper #3, a qualitative study reveals Demand Response (DR) aggregators as institutional entrepreneurs that struggle to reform the still largely supply-oriented European electricity market. Unfavourable regulation, low value of flexibility, resource constraints, complexity, and customer acquisition are the key challenges DR aggregators face. To overcome them they apply a combination of strategies: lobbying, market education, technological proficiency, and upscaling the business. The study highlights DR aggregation as an architectural innovation that alters the interplay between key actors of the electricity system and provides policy recommendations including the necessity to assess the real value of DR in comparison to other flexibility sources by taking all externalities into account, a technology-neutral approach to market design and the need for simplification of DR programmes, and common standards to reduce complexity and uncertainty for DR providers.
Siliziumorganische Substanzen sind aus dem Alltag kaum wegzudenken. Sie kommen in vielfältiger Form vor und finden durch ihre Stabilität in vielen Produkten des Haushalts und der Industrie Anwendung. Eine Freisetzung in die Umwelt ist unvermeidbar. Siliziumorganische Substanzen konnten bereits in allen Umweltkompartimenten (Luft, Wasser, Boden) analytisch nachgewiesen werden. Welche Risiken von dieser Stoffgruppe ausgehen, ist noch nicht abschließend geklärt. Dennoch gibt es Hinweise auf negative Auswirkungen auf Mensch und Umwelt. Deshalb sollten Strukturen in siliziumorganischen Substanzen untersucht werden, die einen Abbau in der Umwelt begünstigen, um die Akkumulation dieser Stoffe in der Umwelt zu verringern. Dafür wurden diverse biotische und abiotische Abbautests mit unterschiedlichen siliziumorganischen Substanzen durchgeführt. Der Fokus der vorliegenden Arbeit lag vor allem in der biologischen Abbaubarkeit der Substanzen. Es wurden die Organisation for Economic Co-operation and Development (OECD)-konformen Tests Closed-Bottle-Test (CBT, OECD 301D) und Manometrischer Respirationstest (MRT, OECD 301F) durchgeführt. Die Hydrolysierbarkeit wurde mithilfe des Hydrolysetests OECD 111 bei unterschiedlichen pH-Werten untersucht. Bei bestimmten Substanzgruppen ohne biologischen Abbau wurde das Verhalten der Substanzen bei Bestrahlung mit verschiedenen Bestrahlungsquellen untersucht. Die Analyse der Primärelimination der siliziumorganischen Substanzen erfolgte je nach Substanzeigenschaften mithilfe der Hochleistungsflüssigkeitschromatografie gekoppelt mit einem Spektrometer mit ultraviolettem und sichtbarem Licht (HPLC-UV/Vis) oder der Gaschromatografie gekoppelt mit einem Massenspektrometer (GC-MS). Die Transformationsprodukte wurden hingegen mithilfe der Flüssigkeitschromatografie gekoppelt mit einem Mehrfach-Massenspektrometer (LC-MSn) analysiert. Für eine umfassende Bewertung des biologischen Abbaus von siliziumorganischen Substanzen wurden ein Vergleich mit analogen Kohlenstoffverbindungen und eine Aufstockung mit Daten aus der Datenbank der Europäischen Chemikalien Agentur (ECHA) durchgeführt. Die Gruppierung der Substanzen nach ihren Strukturmerkmalen wurde hinzugezogen, um Rückschlüsse auf die Abbaubarkeit zu ziehen. Eine besser biologisch abbaubare Grundstruktur brachte für die Benzenderivate keine Verbesserung der biologischen Abbaubarkeit. Dennoch hatte die Einführung von +M-Gruppen am Aromaten einen positiven Einfluss auf die Geschwindigkeit und den Grad des photolytischen Abbaus. Die Bestrahlungsquelle hatte ebenfalls einen deutlichen Einfluss auf die Eliminierungsrate während des Photolyseexperiments. Mit einer Veränderung der Wellenlängen in den kurzwelligen Bereich und der daraus resultierenden energiereicheren Strahlung konnten die Substanzen schneller und teilweise vollständig primär eliminiert werden. Bei allen Abbaupfaden hatte die Hydrolyse eine entscheidende Rolle und wurde als einer der Hauptabbauprozesse charakterisiert. Bei einer Verbindung wurde im Nachgang an die biotischen und abiotischen Abbautests eine ausführliche Aufklärung der elf gebildeten Transformationsprodukte vorgenommen. Um den Einfluss von Silizium in organischen Substanzen auf die biologische Abbaubarkeit zu untersuchen, wurde der direkte Vergleich von siliziumorganischen Substanzen und deren Kohlenstoffanaloga im CBT durchgeführt. Dabei hat sich gezeigt, dass drei von fünf Kohlenstoffverbindungen und keine siliziumorganische Verbindung als leicht biologisch abbaubar eingestuft werden konnten. In allen bis auf einen Fall konnten für die Kohlenstoffverbindungen höhere Abbauraten im CBT beobachtet werden. Die Hydrolyse wurde als erforderlicher Schritt vor dem biologischen Abbau von siliziumorganischen Substanzen identifiziert. Das siliziumfreie Produkt der Hydrolyse bestimmte den Grad des biologischen Abbaus. Die gute biologische Abbaubarkeit der einen siliziumorganischen Verbindung resultierte aus der leicht hydrolysierbaren Silizium-Stickstoff-Bindung und der leichten biologischen Abbaubarkeit des siliziumfreien Hydrolyseproduktes. Die siliziumhaltigen Reaktionsprodukte der Hydrolyse waren nicht biologisch abbaubar. Bioabbaudaten aus eigenen Experimenten, aus vorhergehenden in der Arbeitsgruppe durchgeführten analogen Arbeiten und aus der ECHA-Datenbank wurden zusammengetragen, um einen Datensatz zu generieren. Die 182 Substanzen des Datensatzes wurden hinsichtlich ihrer Struktur gruppiert, um allgemeine Erkenntnisse für die biologische Abbaubarkeit von siliziumorganischen Verbindungen abzuleiten. Es gab Gruppen mit Substanzen, die überhaupt nicht biologisch abbaubar waren (z. B. zyklische, lineare und verzweigte Siloxane). Gruppen, die Substanzen mit Ethern, Estern, Oximen, Aminen und Amiden enthielten, waren hydrolyseanfällig, sodass auch leicht biologisch abbaubare Zwischenprodukte gebildet werden konnten. Die siliziumfreien Hydrolyseprodukte waren meist biologisch abbaubar, während die siliziumhaltigen Hydrolyseprodukte persistent waren. Allgemein hat sich gezeigt, dass Modifikationen am Molekül einen positiven Einfluss auf die Abbaubarkeit haben können. Beispielsweise können Heteroatome eine Veränderung der Polarität bzw. der Elektronendichte hervorrufen, was die Photolyse- und Hydrolysefähigkeit und folglich auch den Bioabbau zum Positiven verändern kann. Das Einführen solcher Heteroatome oder funktioneller Gruppen in Polysiloxanketten kann demnach ein vielversprechender Ansatz für leichter abbaubare siliziumorganische Verbindungen sein. Nicht abbaubare Stoffe sollten vermieden werden, wenn sie nach ihrer Verwendung in die Umwelt gelangen.
Understanding that entrepreneurship can be better modeled from a systemic point of view is a primordial aspect that determines the important role of universities in entrepreneurial ecosystems. What makes the ecosystem approach a valuable tool for understanding social systems is that, from a holistic perspective, their behavior seems to have emerging characteristics. This dissertation presents a dual scientific account of the entrepreneurship phenomenon in universities. The work is divided into two equal parts, each of which is composed of two research papers. The narrative of the first half takes on a macro perspective view, consisting of one theoretical and one empirically-based conceptual case study. This part conceptually depicts a systematic approach to entrepreneurialism in higher education, namely an ecosystems perspective. The second half concentrates on the meso- and micro levels of study from the university's point of view, comprising of a case study as historical account for the emergence of the entrepreneurial university, and of a metasynthesis of empirical case studies in entrepreneurial universities, which serves as the basis for the development of entrepreneurial university archetypes. This doctoral work contributes to an in-depth understanding of Entrepreneurship in universities regarding its systemic qualities and archetypal characteristics of entrepreneurial universities. It argues for an ecosystem's perspective on the phenomenon of entrepreneurial activity, highlighting the fundamental role that universities play as the heart of entrepreneurial ecosystems. Furthermore, this research expands on the novel concept of the entrepreneurial university by using extensive case study literature to empirically identify distinct archetypes that better reflect the diverse reality of how universities engage as entrepreneurial actors by way of differentiated entrepreneurial structures, systems, and strategies.
Consisting of three articles and a framework manuscript, this cumulative dissertation deals with sustainable compensation of chief executive officer (CEO) with a focus on climate-related aspects. Against the backdrop of the European action for sustainability and the EU Green Deal, the dissertation pays special attention to the consideration of climate-related aspects of corporate performance in CEO compensation. In this context, sustainable compensation is characterized by the consideration of long-term interests and sustainability of the company as well as by the inclusion of financial and non-financial aspects of environmental, social and governance performance (ESG) in compensation agreements. While this novel instrument of corporate governance aims to incentivize the implementation of sustainability-oriented corporate strategy, it is particularly important to unfold this incentive effect at the individual CEO level in view of their managerial discretion. The framework manuscript discusses the research objectives, the regulatory and theoretical background, the results of the dissertation and their implications in the context of regulation, research, and business practice. The essence of the dissertation are the three articles. The first article examines the current state of empirical research based on 37 articles that were published between 1992 and 2018. Based on a multidimensional research framework, the structured literature review compiles past research findings, identifies contentual and methodological foci in the research area, and derives questions for future research. The second article addresses the topic from a conceptual perspective. Taking the existing work as a starting point, a conceptual framework is derived, which organizes the determinants of carbon-related CEO compensation at societal, organizational, group and individual levels of analysis. On this basis, eight propositions are presented that seek to distinguish between the determinants which support and challenge the implementation of carbon-related CEO compensation. The third article focuses on the use of CO2-oriented performance indicators in CEO compensation. The empirical-qualitative study analyzes corporate disclosure of the 65 largest companies in the EU for the years 2018 and 2019. The study addresses the use of CO2-oriented performance indicators in corporate strategy and CEO compensation. It also examines which compensation components are determined with the help of CO2-oriented performance indicators, which type of performance indicators are used, and whether CO2-intensive and less CO2-intensive companies differ in this regard.
Increasing objections have been formulated towards broadening the security category. Securitisation is used to bring attention to urgent and existential threats that cannot be resolved through ordinary political decisions. During the time of the state of emergency between 2015 and 2017, France strengthened its security forces and introduced generalised surveillance measures to curb the terrorist threat. The purpose of this Bachelor thesis is to problematise the securitisation of terrorism in the French case. To do so, the Just Securitisation Theory by Rita Floyd is used to examine the following research question: Was it just to securitise terrorism in France between 2015 and 2017? Through critical discourse analysis of 54 presidential speech acts and secondary text analysis, this study aims to scrutinise securitising moves and security practices of the French government. The presented results indicate that the justness of securitisation is highly questionable. The analysis shows that the governments set excessive goals of eliminating terrorism and that security measures were misappropriated to fight organised crime instead of terrorism.
The transition of our energy system towards a generation by renewables, and the corresponding developments of wind power technology enlarge the requirements that must be met by a wind turbine control scheme. Within this thesis, the role of modern, model-based control approaches in providing an answer to present and future challenges faced by wind energy conversion systems is discussed. While many different control loops shape the power system in general, and the energy conversion process from the wind to the electrical grid specifically, this work addresses the problem of power output regulation of an individual turbine. To this end, the considered control task focuses on the operation of the turbine on the nonlinear power conversion curve, which is dictated by the aerodynamic interaction of the wind turbine structure and the current inflow. To enable a power tracking functionality, and thereby account for requirements of the electrical grid instead of operating the turbine at maximum efficiency constantly, an extended operational range is explicitly considered in the implemented control scheme. This allows for an adjustment of the produced power depending on the current state of the electrical grid and is one component in constructing a reliable and stable power system based on renewable generation. To account for the nonlinear dynamics involved, a linear matrix inequalities approach to control based on Takagi-Sugeno modeling is investigated. This structure is capable of integrating several degrees of freedom into an automated control design, where, additionally to stability, performance constraints are integrated into the design to account for the sensitive dynamical behavior of turbines in operation and the loading experienced by the turbine components. For this purpose, a disturbance observer is designed that provides an estimate of the current effective wind speed from the evolution of the measurements. This information is used to adjust the control scheme to the varying operating points and dynamics. Using this controller, a detailed simulation study is performed that illustrates the experienced loading of the turbine structure due to a dynamic variation of the power output. It is found that a dedicated controller allows wind turbines to provide such functionality. Additionally to the conducted simulations, the control scheme is validated experimentally. For this purpose, a fully controllable wind turbine is operated in a wind tunnel setup that is capable of generating reproducible wind conditions, including turbulence, in a wide operational range. This allows for an assessment of the power tracking performance enforced by the controller and analysis of the wind speed estimation error with the uncertainties present in the physical application. The controller showed to operate the turbine smoothly in all considered operating scenarios, while the implementation in the real-time environment revealed no limitations in the application of the approach within the experiments. Hence, the high flexibility in adjusting the turbine operating trajectories and structural design characteristics within the model-based design allows for efficient controller synthesis for wind turbines with increasing functionality and complexity.
Considering the recent success of right-wing populist candidates and parties in the United States and across Europe, there has for some years now been talk among scholars (and the wider public) about a worldwide democratic recession. The younger generations appear to be especially unsupportive of democracy’s liberal principles and more willing to express support for authoritarian alternatives. What these authors overlook, however, is that the publics of advanced industrial societies have experienced an intergenerational value shift. In fact, populations in industrial democracies have become more liberal overall, but not everyone’s mindset is changing at the same speed. It is mainly – but not exclusively – the members of the lower classes that do not keep up. While societies have generally become more liberal, there is increasing alienation between the social classes over these liberal values. Drawing on a more recent trend in social class research with a social cognitive approach, this dissertation contributes to the study of growing anti-democratic tendencies around the world by analyzing the interplay between inequality dynamics and value orientations. The focus lies on investigating the effect socio-cultural polarization (i.e., ideological polarization between social classes) has on civic culture in the mature democracies of the West. The findings suggest that it is not ideological polarization between the social classes that has the greatest negative effect on civic culture, or general civic attitudes and behavior, for that matter. It is the increasing dissent in society about whether the country’s elites are still to be trusted with making the right decisions to increase the average citizen’s quality of life. This difference in opinion manifests itself in a decline in some civic attitudes.
In contrast to the U.S., little research on the impact of structural racism in education in Germany has been conducted so far. Also, the Critical Race Theory (CRT) has little to no relevance in education. As school significantly influences the further life of children and young people, equal opportunities must be ensured to prevent the reinforcement of the social division in Germany. Therefore, this work will examine whether findings from studies in the U.S. can be transferred to the German educational system since both countries struggle with a substantial rise in racism, racially motivated violence, and hate.Hence this work aims to answer the following research question: How does the CRT influence the U.S. educational system and to what extent can these findings be transferred to the German context? First, key terms and the Critical Race Theory will be defined, which are at the core of education reforms and controversies in the US. Then, the history of the U.S. will be examined to contextualise the status quo of the educational system in the U.S. With this background knowledge and drawing from the theoretical framework of CRT, recent educational reforms and their impact will be analysed. Lastly, based on these findings, possible implications for Germany will be formulated.
This study examines the perspective of German venture capitalists on the success factors of digital startups and follows an explorative three-dimensional research approach that integrates the micro perspective on the entrepreneurial personality, the macro perspective on the entrepreneurial context, and the meso perspective on the business model. Thus, the study operates in a very young field of entrepreneurship research. One of the purposes of this research project is to work out the significance of particular characteristics at each research level for the economic success of a digital start-up from the perspective of German venture capitalists. Furthermore, the study sheds light on the view of this group of experts on the relevance of an entire group of characteristics. To answer the central research questions, qualitative research methods and a mixed-methods approach are pursued, with quantitative and qualitative primary data being collected by means of theory-driven semi-structured expert interviews. As a result, a total of four articles have been produced: three articles that focus on presenting the results of qualitative research from only one of the three aforementioned research perspectives each, and a fourth article that combines methods from qualitative and quantitative research and derives an integrated, evidence-based working model of the economic success of digital startups from the perspective of German venture capital (VC) investors.
This dissertation contributes to research on generating actionable knowledge for coastal governance to enhance the resilience of coastal social-ecological systems (SES) to climate change. It does this by providing theoretical, methodological and empirical insights on three research questions (RQs). These are: (1) what is a more actionable concept for applying the concept of resilience in coastal governance?; (2) what methods and approaches are suitable to generate actionable knowledge for coastal governance?; (3) what obstacles to knowledge co-production exist for early-career researchers (ECRs) and how can they be overcome? The RQs are addressed in five publications. For answering RQ1, the dissertation applies a research synthesis to bring together common themes and challenges documented in resilience, climate change and environmental governance literature. For answering RQ2, different methods and approaches for generating actionable knowledge are proposed and tested using a case-study in the SES of Algoa Bay, South Africa. These include (i) the analysis of stakeholder agency; (ii) the application of a stakeholder analysis; and (iii) the combination of a capital approach framework, and fuzzy cognitive mapping. Finally, for answering RQ3, the thesis provides a perspective on the obstacles that especially ECRs face, and actions that are needed to create the conditions under which knowledge co-production processes can be successful. This is done by applying a multi-method approach combining an online survey and workshop targeted at ECRs in the marine sciences. Key findings suggest that system and transformative knowledge are particularly important when applying the concept of resilience in coastal governance to generate actionable knowledge. The different methods and approaches that are proposed and tested contribute to generating both system and transformative knowledge. Firstly, they provide an overview of the capacities of different stakeholders to act, shed light on current collaboration and knowledge exchange, and enable the identification of different governance processes for coastal governance and climate change adaptation (system knowledge). Secondly, results have implications for how to improve knowledge exchange and identify leverage points that can enhance overall governance performance, thus providing recommendations on actions and processes that can enhance climate resilience in the case-study area (transformative knowledge). It is also highlighted how knowledge co-production can contribute to generating system and transformative knowledge together with stakeholders, and what actions are needed to build the capacities to translate knowledge into action. Additionally, the findings of this dissertation put forward actions that are needed at different organisational levels of the academic system to facilitate knowledge co-production processes with stakeholders involved in coastal governance. The results of this dissertation have implications for stakeholders and decision-making in the case-study area, as well as for environmental governance, climate change adaptation and broader sustainability research. Implications for stakeholders include recommendations for implementing formal commitments to share climate information across levels and sectors, establishing the role of information providers in the municipality, and reinforcing human capital within the local municipality in Algoa Bay. Findings also suggest the need for a more integrated approach to climate change adaptation in coastal planning and management frameworks. It also suggests that the conservation of environmental assets presents an important bottleneck for resilience management and needs to be further prioritised within decision-making. Implications for research include the applicability of methods beyond the context of this dissertation; a more actionable concept for approaching resilience in (coastal) governance systems; and a more critical reflection on how transformative research is conducted, and what academic foundation is needed so that it can fulfil its societal goal.
This research argues that the emergent driverless car, as a kind of autonomous vehicle, is a Foucault-ian "ethical apparatus", working as an epistemic device to materially embody and enable discursive power by generating notions of "autonomy" and "ethical decision-making". The ethical implications of AI, algorithmic, and autonomous technologies are topics of current regulatory and academic concern. This concern relates to the lack of meaningful oversight of black boxes inside AI systems, liabilities for manufacturers, and inadequate frameworks to hold AI-based socio-technical systems to account. One recent artefact, the driverless car, has taken on these concerns quite literally in the shaping of a niche discourse of the "ethics of autonomous driving". Ambitions to produce a fully autonomous vehicle based on AI technologies are constrained by speculative concerns that its decision-making in unexpected accident situations cannot be assumed to protect humans. "The ethics of autonomous driving" evaluates proposals to build "ethical machines" by examining the relationship between structures of human values and moral decision-making, and how they comport to computational architectures for decision-making. This is the first case this work takes up, chiefly organised around an analysis of a thought experiment, the Trolley Problem, and the online game, Moral Machine, that crowdsourced values to suggest approaches to an "ethics of autonomous driving". Rather than evaluate the feasibility or appropriateness of these two approaches, this work attends to the more critical issue that ethics is being proposed in terms of technologies turning on the logics of risk, speculation, and probabilistic correlations that are fundamental to how machine learning makes decisions. The concern in this work is less a normative framework or approach for a better or more appropriate ethics of autonomous driving. Rather, this work argues that what we understand as "the ethical" is being transformed when architected by, through, and for Artificial Intelligence / autonomous technologies to become their own regulators. Hence the production of autonomous driving necessitates computational infrastructures that are creating a world legible to and for the navigation of a driverless car. The author argues that this is fostering computational governance that has implications for human bodies and social relations, chiefly that conventional approaches to regulation and accountability attend to human values and decision-making rather than computational ones. A second case that this research examines is that of driverless car crashes, to examine how "autonomous" driving requires substantial embodied human knowledge and micro-work. Taken together, these two cases make an argument for how myriad practices of knowledge-production are translating the human world into something legible to the navigational needs of the car, producing changes in the human world through the actions of the car on that basis, and advancing notions of "autonomy". This work concludes with arguments for a critical reconceptualisation of ethics and ethical decision-making in AI / autonomous systems.
This thesis deals with sustainability in African Higher Education Institutions (HEIs) and the influence of language in achieving sustainable development. Several authors highlight the existing imbalance of sustainability research in higher education, with most publications focusing on the so-called Global North. Little is known about sustainability in the so-called Global South, and in African educational institutions in particular. The first article of this thesis investigated existing sustainability activities in African HEIs. Rather than focusing on the shortcomings, the paper took a positive stance, opposing the predominant language of deficits in research on Africa. In the Delphi study conducted, 32 experts from 29 HEIs in 16 African countries described the sustainability activities they are engaging in. Experts provided information about their experiences in their respective HEI, while language and culture emerged as areas in need of further research. The second article therefore focused on the relationship between language and education for sustainable development in African educational institutions, and systematically reviewed scholarly literature regarding this connection. Authors of the reviewed 33 papers approached this connection mainly on a theoretical and philosophical level, focusing on education and Africa as a whole rather than specified forms of education in specific countries. The third article examined the views of Tanzanian higher education students and graduates regarding language and sustainability. Participants explained how they integrate sustainability and the Sustainable Development Goals (SDGs) into their research and how they approach translations in the process. In the ensuing interviews, participants estimated that only a fraction of people outside of academia are aware of sustainability and the SDGs, rendering the achievement of target 4.7 unlikely. This thesis therefore contributes to a better understanding of the current challenges in implementing sustainability and the SDGs in African educational institutions. It highlights the need to integrate (local) African languages in order for sustainability activities as well as the SDGs to be successful.