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While in some Eastern European countries a wave of colored revolutions challenged existing political orders, Belarus has remained largely untouched by mass protests. In Minsk, the diffusion of democratic ideas leading to the mobilization of population meets a stable authoritarian regime. Nevertheless, the stagnating democratization process cannot be only attributed to the strong authoritarian rule and abuse of power. Indeed, Belarusian president Alexander Lukashenko still enjoys popularity by a large part of the population. Although international observers report that elections in Belarus have never been free and fair, few commentators doubt that Lukashenko would not have won in democratic elections. This evidence suggests that the regime succeeded in building a strong legitimizing basis, which has not been seriously challenged during the last two decades. This paper explores the authoritarian stability in Belarus by looking at the patterns of state ideology. The government effectively spreads state ideology since the early 2000s. Ideology departments have been created in almost all state institutions. The education sector has been affected by the introduction of the compulsory course "The Fundamentals of Belarusian State Ideology" at all universities, and increasing attention to the patriotic education at schools. Based on document analysis, I trace the creation of "ideological vertical" in Belarus and focuse on the issue of ideology in education and youth policy sectors.
This cumulative thesis consists of six single contributions: five independent essays and an introductory chapter. All of the conributions have been published or accepted for publication. The overarching scope of these essays is to analyze different factors accounting for the stability of post-Soviet authoritarian regimes and the obstacles, which Western democracy promoters can face when dealing with autocrats. The starting point for these enquiries has been the striking inability of Western democracies and in particular of the European Union to encourage and to assist political transformation in the majority of the post-Soviet republics.
Data management is a cornerstone for any kind of information system - including the aerospace and aviation sector. In contrast to conventional domains, software development in the avionics domain must adhere to a legally binding certification process, called qualification. The success of the process depends on compliance with international standards, such as DO-178: Software Considerations in Airborne Systems and Equipment Certification. From a software developer's perspective, challenges arise in terms of methods and tools. Techniques that have a potential impact on the deterministic and predictable execution of avionics software are prohibited.
The objective of this thesis' research is to develop a scalable method to realize data-management for multi-variant avionics software under the restrictions and constraints of the domain. Since avionics software faces very long-term life-cycles (up to 75 years), a particular focus is being placed on maintenance and evolution. Based on the insights gained in a semi-structured interview at Airbus Helicopters, industrial established approaches to implement qualified avionics software are assessed at first and compared with respect to strengths and weaknesses for data-management afterwards. As a result, a novel development approach is proposed, combining model-based techniques and product-line technology to derive the source code of highly specific data-management variants, as well as the majority of assets required for the qualification process, from a declarative system specification.
In order to demonstrate the practicability of the approach in industry, a framework is presented that is deployed and applied at Airbus Helicopters to generate qualifiable data-management components for the variants of the NH90 helicopter. The maintainability is shown by means of a domain-specific optimization, in which the model-based and generative approach is used to establish safe memory overlays at compile-time. Key findings reveal a substantially reduced memory footprint (29,1% in case of a real-world scenario), as well as an significantly facilitated implementation process, which would not be accomplishable using conventional methods for software development in the avionics domain.
Data is an important competitive resource in digital online markets. As a result, the access and availability of data can be the basis for a competitive advantage. This thesis analyzes the role and competitive effects of data in digital markets and contributes to an improved understanding of data as a (potential) basis for market power. Thereby, the thesis also contributes to the ongoing policy debate on how to safeguard a fair and open competitive environment for internet-based digital (i.e., online) services as well as traditional services.
In doing so, Study 1 surveys the literature and discusses (i) the challenges that are associated with assessing market power in digital markets, (ii) the challenges in creating a level playing field in digital markets, e.g., by harmonizing regulatory obligations for online and offline services, and (iii) the vital role of data and data protection in the context of data-driven business models. Study 2 and Study 3 focus on the competitive effects of transferring data between online competitors. The study on social logins (Study 2) highlights the strategic effects as well as welfare implications if competing online services deliberately and voluntarily decide to share user and usage data. Whereas Study 2 abstracts from the user’s decision how much data to provide to an online service, Study 3 focuses on the amount of data that firms require for their services and that is provided by users. In particular, Study 3 investigates the competitive and welfare effects of a new fundamental consumer right: The right to data portability. This right is part of the General Data Protection Regulation (GDPR) which becomes effective in May 2018 for all online services available to users in the European Union and allows users to transfer their personal data from one online service to another (competing) online service (c.f., GDPR Article 20). In this context, the study examines the firms’ strategic reactions to the introduction of such a right and identifies the ensuing market outcomes as well as policy and managerial implications.
In conclusion, this doctoral thesis contributes to an improved understanding of (i) the competitive effects that arise from data as an economic good or valuable asset for digital services, and (ii) the aspects that may constitute market power in digital markets. Moreover, from a policy perspective, the thesis can be understood as a theoretically founded research project that (i) informs which market failures may arise in the context of digital (data-driven) markets and that (ii) highlights the peculiarities that need to be considered to define appropriate legal requirements in order to establish a level playing field between online services and traditional (established) services, but also between competing online services. Therefore, the thesis also contributes to the discussion on whether and how dominant online platforms should and can be regulated.
Information has a particular importance in online purchase decision processes. As opposed to consumers in online markets, consumers in online markets cannot inspect the physical product to evaluate it and reduce their perceived risk. Hence, consumers in online markets are dependent upon the information that they can gather about a product in which they are interested. Therefore, they have two primary sources of information: Product descriptions and customer reviews. Both sources affect consumers’ purchase decision processes and hence have an economic impact for consumers, shop providers and manufacturers. It is important to know how these sources of information influence a customer’s online purchase decision and how to extract the relevant information.
To examine these research objectives, several studies applying different methodological approaches have been conducted. The results are presented in this dissertation.
Ausgehend von den gattungsspezifischen Besonderheiten des Historienfilms zeigt Thomas Wegener anhand zahlreicher Beispiele, dass der historische Spielfilm höchst eklektizistische Geschichtsbilder (nach)zeichnet. Diese Geschichtsbilder basieren einerseits überwiegend auf Vorstellungen des 19. Jahrhunderts, andererseits auf einer aus dem Faschismus bekannten Bildsprache. Keiner der Filme berücksichtigt den aktuellen historischen Forschungsstand. Vielmehr kommentieren die dargestellten, vergangenen, Welten aktuelle Ereignisse und Konflikte und spiegeln rezente Werte und Normen wider. Daher scheint es, so Thomas Wegener, für die historiographische Forschung sinnvoller zu sein, weniger nach dem „richtig“ oder „falsch“ zu fragen, sondern angesichts der enormen Breitenwirkung des Medium Films zu erörtern, wie genau Geschichte im Spielfilm gedacht und inszeniert wird.
Smart Grids integrate currently isolated power and communications networks, while introducing several new technologies on the hardware and software sides. One of the most important ingredients is the potential for demand-response programs, which offer the possibility of sending instructions to consumers to adapt their power consumption over a certain period of time. However, high-frequency data collection exposes consumers’ usage behaviors, leading to security and privacy challenges for Smart Grids.
In this thesis, three cryptographic schemes are constructed for different demand-response programs. In the mandatory incentive-based demand-response program, privacy preservation depends on the power consumption of consumers. An anonymous authentication scheme is constructed for overload auditing and privacy preservation. Consumers’ identities are anonymous during normal operation. The operation center defines an acceptable consumption threshold at times of power shortage. Consumers must follow the instruction and curtail their power consumption to meet the threshold. If they do so, the consumers keep their anonymity, while disobedient consumers, whose power consumption exceeds the threshold, can be identified. Security analysis demonstrates that the constructed anonymous authentication scheme is secure in a random oracle model. In the voluntary incentivebased demand-response program, consumers are categorized as either obedient or disobedient consumers according to their consumption curtailment. Consumers utilize a homomorphic encryption algorithm to encrypt their usage and report the ciphertexts to the operation center periodically. At a time of grid instability, the obedient consumers reduce their consumption and prove their curtailment by using a range proof. Both the usage reports and the proofs from obedient consumers concerning their consumption are reported without leaking private information. In order to achieve the real-time requirement, a security model is proposed and a batch verification algorithm is constructed, which is proved to be secure in the defined oracle model. Apart from reward and penalty detection in demand-response programs, theft detection is also an important requirement in Smart Grids. In order to achieve theft detection, this thesis employs the dynamic k-times anonymous authentication and blind signatures to create an efficient theft detection mechanism in the prepaid card system, where consumers pay for their consumption in advance and obtain credentials. A consumer sends the credentials anonymously and obtains corresponding credentials during times of consumption. If a thief tries to send reused credentials to steal electricity, his anonymity will be revoked. Finally, this thesis proves that the proposed mechanism finds the real identities of power thieves, without sacrificing the privacy of honest consumers under the random oracle model.
Für Monumentalbauten als Teil unseres Kulturgutes im Speziellen als auch für Gebäude im Allgemeinen, wurden im Rahmen des MonArch- rojektes verschiedene Methoden zur digitalen Speicherung von Informationen über Monumentalbauten erforscht. Das daraus entstandene MonArch-System ist für die Dokumentation von Monumentalbauten verwendbar und speichert das digitale Modell des Bauwerks in einer relationalen Datenbank. Das digitale Modell des Bauwerks entsteht durch eine Segmentierung in Gebäudeteile, die dann in einer Strukturhierarchie zusammengefasst werden können. Als Strukturhierarchie versteht man in diesem Zusammenhang eine Hierarchie von Gebäudeteilen, die in einer Teil-von-Beziehung stehen. Die Strukturhierarchie erlaubt es Informationen z.B. Dokumente mit einem räumlichen Bezug auszuzeichnen. Zusätzlich wird eine Themenhierarchie unterstützt, die es erlaubt Informationen thematisch mit Begriffen zu beschreiben.
Betrachtet man räumliche und thematische Anfragen in vernetzten MonArch-Systemen, in denen sich mehrere Gebäudearchive zusammenschließen, ist diese starke Bindung der Information an die einzigartige Struktur jedes Gebäudes ein Hindernis für ein einfaches Verfahren zur räumlichen Suche. Da sich jedes Gebäude in seinem speziellen strukturellen und räumlichen Aufbau unterscheidet, liefert eine räumliche Anfrage, die speziell auf diese Eigenheiten eines Gebäudes ausgerichtet ist, für andere Gebäude keine Suchergebnisse. Für thematische Anfragen stellen nicht kompatible Themenhierarchien ein Hindernis dar, die eine übergreifende thematische Anfrage verhindern. Die größte Herausforderung ist es, Struktur- und Themenhierarchien aufeinander abzubilden.
Zur Lösung des geschilderten Problems wird in vernetzten Informationssystemen auf eine geeignete Transformation der ursprünglichen Anfrage zurückgegriffen, um den Anfragefokus zu erweitern (Relaxation) oder eine Anpassung an die Gegebenheiten des entfernten Informationssystems zu erreichen (Transformation). Das Anfragetransformations- und -relaxationsverfahren, das in dieser Arbeit vorgestellt wird, nutzt eine Generalisierungsbeziehung aus, um ausgehend von einer Anfrage an eine spezielle Struktur- und Themenhierarchie eine automatische Transformation der Anfrage durchzuführen. Bei Themenhierarchien sind gemeinsame Oberthemen ein Ansatzpunkt. Bei Strukturhierarchien können Typinformationen zu Gebäudeteilen die Generalisierungsbeziehung darstellen. Die transformierte und dadurch relaxierte Anfrage kann dann an ein Netzwerk von MonArch-Systemen gestellt werden, ohne dass eine manuelle Auswahl der Gebäudeteile in anderen Strukturhierarchien oder eine angepasste Themenauswahl erfolgen muss. Dazu muss die Strukturhierarchie der anderen Gebäude im Netzwerk von MonArch-Systemen nicht bekannt sein. Im Rahmen der vorliegenden Arbeit werden verschiedene Relaxationsverfahren, z.B. ein angepasstes Spreading-Activation-Verfahren, zur automatischen Anfragetransformation von räumlichen und thematischen Anfragen vorgestellt, mit dem Ziel eine vollständige Abbildung zwischen den Strukturhierarchien von Gebäuden und Themenhierarchien zu vermeiden. Erreicht wird das Ziel durch eine Erweiterung des MonArch-Datenmodells und eine Verallgemeinerung der MonArch-Anfragen, die eine Anfragetransformation zum Anfragezeitpunkt erlauben.
An increasing number of companies report that eco-sustainable initiatives have a positive impact on firms’ economic performance and concurrently allow the combination of social and commercial goals by optimizing environmental and economic decisions simultaneously. These initiatives are considered an integral part of organizational sustainability transformations, which are a special case of multilayered, complex organizational change efforts that relate to environmental, organizational, and individual factors. Institutional logics and information systems (IS) have shown to be two important perspectives from which to explore mechanisms and processes central to organizational sustainability transformations. Institutional logics offer a unique perspective to investigate organizational change for sustainability because they provide a new approach to organizational change that incorporates macro structures, culture, and agency to explain how actions are enabled or constrained. It thus allows for insights into the complex and miscellaneous interplay of external and internal determinants that govern organizational transformation processes towards sustainability. By providing insights into institutional changes of practice and behaviors, an institutional logic perspective allows for a detailed analysis of organizational transformations. Within these change processes, IS have shown to be an efficient and pervasive tool to leverage sustainability by integrating human and technological factors. Since IS have become a key resource for the encouragement of organizational sustainability transformations, adopting an IS perspective allows for an understanding of mechanisms and processes that enable IS to foster sustainability in organizations. Thus, this dissertation draws on four studies by investigateing an institutional logic perspective as well as an IS perspective to explore organizational sustainability transformations and facilitate an in-depth understanding of organizational, human, and technological factors that encourage sustainability in organizational transformations.
Der deutsche Markt für Abschlussprüfungen: Marktstruktur, Regulierungsmaßnahmen und Prüferwechsel
(2018)
Diese Dissertation ist eine empirische Untersuchung über die Entwicklung des deutschen Markts für Abschlussprüfungen in den Jahren 2005 bis 2014. Das Ziel ist es, eine Beurteilung über die Notwendigkeit, die Auswirkungen sowie die Zielerreichung regulatorischer Eingriffe in diesem Zeitraum abzugeben. Dabei folgt die Arbeit einer Dreiteilung. Die Analyse der Marktstruktur soll u. a. über die Notwendigkeit der Einführung rechtlicher Normen Aufschluss geben. Auf Basis der Untersuchung von Regulierungsmaßnahmen werden Auswirkungen sowie die Zielerreichung dieser Normen untersucht. Eine Ereignisstudie zur Kapitalmarktreaktion auf Prüferwechsel soll schließlich die Einschätzung des Kapitalmarkts gegenüber der kontrovers diskutierten Regulierungsmaßnahme einer externen Rotationspflicht aufzeigen. Die methodische Vorgehensweise basiert auf Mehrebenenmodellen. Mit einem Paneldatensatz von 2.636 Beobachtungen (353 Unternehmen) weist die Arbeit eine der umfangreichsten Basisstichproben der deutschen Prüfungsmarktforschung auf. Die Resultate zeigen, dass die Notwendigkeit für regulatorische Eingriffe durch die analysierte Erhöhung der Prüferunabhängigkeit im Untersuchungszeitraum gerechtfertigt werden kann. Hinsichtlich der Auswirkungen ergeben sich ein Anstieg der Prüferhonorare sowie eine Verringerung der Bilanzpolitik. Die Zielerreichung einer Stärkung der Prüferunabhängigkeit sowie einer Erhöhung der Qualität der Abschlussprüfung kann zudem nachgewiesen werden. Zuletzt wird aufgezeigt, dass der Kapitalmarkt negativ auf Prüferwechsel reagiert.