@phdthesis{Abel2020, author = {Abel, Johannes}, title = {Politischer Radikalismus innerhalb des Social Web. Eine Analyse g{\"a}ngiger Narrative und diskursiver Strategien rechter Akteure}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-8803}, school = {Universit{\"a}t Passau}, pages = {177, XXXIII Seiten}, year = {2020}, abstract = {Ziel der Arbeit ist es, Narrative und diskursive Strategien von politisch rechten Akteuren zu erforschen und aus einer p{\"a}dagogischen Sicht zu bewerten. Der Fokus der Untersuchung wird hierbei auf Kommunikation innerhalb des Social Web gelegt. Zur Bew{\"a}ltigung des Forschungsvorhabens wird als Methode eine Diskursanalyse angewendet. Die Analyse kommt zu dem Ergebnis, dass sowohl die erzeugten Narrative als auch die verwendeten diskursiven Strategien in allen untersuchten diskursiven Arenen starke {\"A}hnlichkeiten aufweisen - unabh{\"a}ngig davon, ob die Arena vorrangig rechtsextreme, rechtsradikale oder rechtspopulistische Tendenzen besitzt. Dies legt den Verdacht nahe, dass ein Großteil der politisch rechte Akteure immer wiederkehrende Narrative verbreiten und diese mit den stets gleichen diskursiven Strategien untermauern, eine klare diskursive Grenze zwischen Rechtsextremismus, Rechtsradikalismus und Rechtspopulismus scheint es nicht zu geben. Dadurch besteht die Gefahr, dass Rechtsextreme Gedanken zunehmend in die Mitte der Gesellschaft vordringen k{\"o}nnen.}, language = {de} } @article{AdamKraemer2022, author = {Adam, Marc T. P. and Kr{\"a}mer, Jan}, title = {Evaluating the emotional bidding framework: new evidence from a decade of neurophysiology}, series = {Electronic Markets}, volume = {2022}, journal = {Electronic Markets}, number = {32}, publisher = {Springer Nature}, address = {Berlin}, doi = {10.1007/s12525-022-00555-x}, url = {http://nbn-resolving.de/urn:nbn:de:101:1-2022080421114680906980}, pages = {1529 -- 1540}, year = {2022}, abstract = {Ten years ago the "emotional bidding framework" (Adam et al., Electronic Markets, 21(3), 197-207, 2011b) was published in this journal. It provided a conceptualization for the role of human emotion in electronic auctions along six propositions on how emotions emerge during the auction process and affect auction outcomes. While the framework emphasized the importance of immediate emotional responses and momentary changes in the bidders' emotional state, the original articledid not include an evaluation of its propositions given the limited data on how bidders experience emotions in the moment that they occur. Ten years on, advances in the growing research field of NeuroIS allow to evaluate the propositions based on neurophysiological evidence. As a rejoinder of the original article, the present paper synthesizes these insights, refines the framework further, and identifies fruitful areas for future research based on remaining gaps in the body of knowledge.}, language = {en} } @article{Adiatu2024, author = {Adiatu, Afeez}, title = {Energizing the inter-regional cooperation and energy governance : an exploration of the Africa-EU energy partnership}, series = {Journal of Sustainable Development of Energy, Water and Environment Systems (ISSN: 1848-9257, DOI: 10.13044/j.sdewes)}, volume = {2024}, journal = {Journal of Sustainable Development of Energy, Water and Environment Systems (ISSN: 1848-9257, DOI: 10.13044/j.sdewes)}, number = {12(4)}, publisher = {SDEWES Centre}, address = {Zagreb}, doi = {10.13044/j.sdewes.d12.0517}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-15782}, pages = {21 Seiten}, year = {2024}, abstract = {The emergence of change in the global energy governance structure is precipitated by the shift in global energy technology. The shift from carbon-intense energy to cleaner sources surpasses technological discontinuation. The inter-regional, regional, and sub-regional grouping emerged in global energy governance to support governance capabilities across countries. This research seeks to investigate the inter-regional partnership between Africa and the European Union initiated to facilitate energy decision-making. This study adopts thematic analysis to explore literature and reports on the Africa-EU partnership to understand its impact on the future of the African energy sector. This research argues using a neo-liberal lens that the limited state capacity in energy governance may necessitate inter-regional partnerships to aid energy sector development in Africa. The study concludes that considering Africa's potential in renewable energy sources such as solar irradiation and the limited energy access in the Sub-Saharan region, intervention of external capabilities through technological and financial aids may stimulate the utilization of such potential.}, language = {en} } @article{AistleitnerFruehwirthProchno2024, author = {Aistleitner, Christoph and Fr{\"u}hwirth, Lorenz and Prochno, Joscha}, title = {Diophantine conditions in the law of the iterated logarithm for lacunary systems}, series = {Probability Theory and Related Fields (ISSN: 1432-2064)}, volume = {192}, journal = {Probability Theory and Related Fields (ISSN: 1432-2064)}, number = {1}, publisher = {Springer}, address = {Berlin/Heidelberg}, issn = {0178-8051}, doi = {10.1007/s00440-024-01272-6}, url = {http://nbn-resolving.de/urn:nbn:de:101:1-2406190937284.886045166092}, pages = {545 -- 574}, year = {2024}, abstract = {It is a classical observation that lacunary function systems exhibit many properties which are typical for systems of independent random variables. However, it had already been observed by Erdős and Fortet in the 1950s that probability theory's limit theorems may fail for lacunary sums (sum f(n_k x)) if the sequence ((n_k)_{k ge 1}) has a strong arithmetic "structure". The presence of such structure can be assessed in terms of the number of solutions k, l of two-term linear Diophantine equations (an_k - bn_l = c). As the first author proved with Berkes in 2010, saving an (arbitrarily small) unbounded factor for the number of solutions of such equations compared to the trivial upper bound, rules out pathological situations as in the Erdős-Fortet example, and guarantees that (sum f(n_k x)) satisfies the central limit theorem (CLT) in a form which is in accordance with true independence. In contrast, as shown by the first author, for the law of the iterated logarithm (LIL) the Diophantine condition which suffices to ensure "truly independent" behavior requires saving this factor of logarithmic order. In the present paper we show that, rather surprisingly, saving such a logarithmic factor is actually the optimal condition in the LIL case. This result reveals the remarkable fact that the arithmetic condition required of ((n_k)_{k ge 1}) to ensure that (sum f(n_k x)) shows "truly random" behavior is a different one at the level of the CLT than it is at the level of the LIL: the LIL requires a stronger arithmetic condition than the CLT does.}, language = {en} } @phdthesis{Alhamzeh2023, author = {Alhamzeh, Alaa}, title = {Language Reasoning by means of Argument Mining and Argument Quality}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-12699}, school = {Universit{\"a}t Passau}, pages = {ix, 154 Seiten}, year = {2023}, abstract = {Understanding of financial data has always been a point of interest for market participants to make better informed decisions. Recently, different cutting edge technologies have been addressed in the Financial Technology (FinTech) domain, including numeracy understanding, opinion mining and financial ocument processing. In this thesis, we are interested in analyzing the arguments of financial experts with the goal of supporting investment decisions. Although various business studies confirm the crucial role of argumentation in financial communications, no work has addressed this problem as a computational argumentation task. In other words, the automatic analysis of arguments. In this regard, this thesis presents contributions in the three essential axes of theory, data, and evaluation to fill the gap between argument mining and financial text. First, we propose a method for determining the structure of the arguments stated by company representatives during the public announcement of their quarterly results and future estimations through earnings conference calls. The proposed scheme is derived from argumentation theory at the micro-structure level of discourse. We further conducted the corresponding annotation study and published the first financial dataset annotated with arguments: FinArg. Moreover, we investigate the question of evaluating the quality of arguments in this financial genre of text. To tackle this challenge, we suggest using two levels of quality metrics, considering both the Natural Language Processing (NLP) literature of argument quality assessment and the financial era peculiarities. Hence, we have also enriched the FinArg data with our quality dimensions to produce the FinArgQuality dataset. In terms of evaluation, we validate the principle of ensemble learning on the argument identification and argument unit classification tasks. We show that combining a traditional machine learning model along with a deep learning one, via an integration model (stacking), improves the overall performance, especially in small dataset settings. In addition, despite the fact that argument mining is mainly a domain dependent task, to this date, the number of studies that tackle the generalization of argument mining models is still relatively small. Therefore, using our stacking approach and in comparison to the transfer learning model of DistilBert, we address and analyze three real-world scenarios concerning the model robustness over completely unseen domains and unseen topics. Furthermore, with the aim of the automatic assessment of argument strength, we have investigated and compared different (refined) versions of Bert-based models that incorporate external knowledge in the decision layer. Consequently, our method outperforms the baseline model by 13 ± 2\% in terms of F1-score through integrating Bert with encoded categorical features. Beyond our theoretical and methodological proposals, our model of argument quality assessment, annotated corpora, and evaluation approaches are publicly available, and can serve as strong baselines for future work in both FinNLP and computational argumentation domains. Hence, directly exploiting this thesis, we proposed to the community, a new task/challenge related to the analysis of financial arguments: FinArg-1, within the framework of the NTCIR-17 conference. We also used our proposals to react to the Touch{\´e} challenge at the CLEF 2021 conference. Our contribution was selected among the «Best of Labs».}, language = {en} } @phdthesis{Ali2011, author = {Ali, Rashid}, title = {Weyl Gr{\"o}bner Basis Cryptosystems}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus-23195}, school = {Universit{\"a}t Passau}, year = {2011}, abstract = {In this thesis, we shall consider a certain class of algebraic cryptosystems called Gr{\"o}bner Basis Cryptosystems. In 1994, Koblitz introduced the Polly Cracker cryptosystem that is based on the theory of Gr{\"o}bner basis in commutative polynomials rings. The security of this cryptosystem relies on the fact that the computation of Gr{\"o}bner basis is, in general, EXPSPACE-hard. Cryptanalysis of these commutative Polly Cracker type cryptosystems is possible by using attacks that do not require the computation of Gr{\"o}bner basis for breaking the system, for example, the attacks based on linear algebra. To secure these (commutative) Gr{\"o}bner basis cryptosystems against various attacks, among others, Ackermann and Kreuzer introduced a general class of Gr{\"o}bner Basis Cryptosystems that are based on the difficulty of computing module Gr{\"o}bner bases over general non-commutative rings. The objective of this research is to describe a special class of such cryptosystems by introducing the Weyl Gr{\"o}bner Basis Cryptosystems. We divide this class of cryptosystems in two parts namely the (left) Weyl Gr{\"o}bner Basis Cryptosystems and Two-Sided Weyl Gr{\"o}bner Basis Cryptosystems. We suggest to use Gr{\"o}bner bases for left and two-sided ideals in Weyl algebras to construct specific instances of such cryptosystems. We analyse the resistance of these cryptosystems to the standard attacks and provide computational evidence that secure Weyl Gr{\"o}bner Basis Cryptosystems can be built using left (resp. two-sided) Gr{\"o}bner bases in Weyl algebras.}, subject = {Gr{\"o}bner-Basis}, language = {en} } @techreport{AlmainiAnthuberEggeretal.2026, author = {Almaini, Amar and Anthuber, Stefan and Egger, Gottfried and Grabner, Daniel and Gutbrod, Amelie and Herburger, Michael and Holzer, Laura and Icyer, Abdurrahman and Katzenbeisser, Stefan and Kraxberger, Manuel and Kufner, Sven and Langner, Karoline and Lill, Bjarne and Mexis, Nico and Pichler, Julia and Plasch, Michael and Sauerwein, Clemens and Schramm, Martin and Szilagyi, Daniel and Wagner, Carina and Zeisler, Alexander}, title = {Cyber-Security und Resilienz in Supply Chains mit Fokus auf KMU}, organization = {FH Ober{\"o}sterreich - Logistikum}, doi = {10.15475/cyseres_kmu.2026}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-20549}, pages = {IX, 115 Seiten}, year = {2026}, abstract = {Dieser Best Practice Guide zeigt, wie kleine und mittlere Unternehmen (KMU) ihre Cyber-Resilienz umfassend st{\"a}rken k{\"o}nnen, von der technischen Basis {\"u}ber Lieferketten und Unternehmenskultur bis hin zu Notfallmanagement und OT-Security. Da Cyberangriffe zunehmend komplexer werden und menschliches Verhalten weiterhin in {\"u}ber 80 \% der Vorf{\"a}lle eine entscheidende Rolle spielt, reicht technische Absicherung allein nicht aus. Entscheidend ist ein integrierter Ansatz, der Mindset (sicherheitsbewusste Haltung), Skillset (praktisches Wissen und regelm{\"a}ßige Schulungen) und Toolset (ad{\"a}quate technische L{\"o}sungen) miteinander verbindet. Der Cyber-Security Grundschutz vermittelt KMU praxisnahe Schritte zur Identifikation des IST-Zustands, zur Priorisierung von Schutzmaßnahmen und zur Einf{\"u}hrung eines kontinuierlichen Verbesserungsprozesses nach dem PDCA-Modell. Das Supply Chain Cyber-Security Handbuch verdeutlicht, wie digital vernetzte Lieferketten zu kritischen Angriffspunkten werden k{\"o}nnen und unterst{\"u}tzt Unternehmen dabei, relevante Partner zu identifizieren, zu klassifizieren und risikobasierte Maßnahmen zu implementieren. Das Awareness- \& Kultur-Handbuch zeigt, wie eine „Security-First"-Kultur entsteht, die Cybersicherheit als Teamaufgabe begreift und {\"u}ber Zero-Trust-Prinzipien, klare Verantwortlichkeiten und moderne Lernformate wie Serious Games nachhaltig verankert. Das Cyber-Notfallkonzept bietet KMU einen strukturierten Leitfaden zur Vorbereitung, Reaktion und Wiederherstellung bei Sicherheitsvorf{\"a}llen - inklusive Checklisten, Rollenmodellen und Incident-Response-Pl{\"a}nen, um Ausfallzeiten zu minimieren und handlungsf{\"a}hig zu bleiben. Erg{\"a}nzend vermittelt das OT-Security Handbuch die Besonderheiten industrieller Systeme und zeigt, wie KMU ihre Produktionsumgebungen sch{\"u}tzen k{\"o}nnen - von der Bewertung kritischer Anlagen {\"u}ber sichere Konfigurationen bis zur schrittweisen Umsetzung praxistauglicher OT-Security-Maßnahmen. Gemeinsam bilden die f{\"u}nf Handb{\"u}cher ein ganzheitliches Rahmenwerk, das KMU bef{\"a}higt, Cybersicherheit als festen Bestandteil des Arbeitsalltags zu verankern, Risiken entlang der gesamten Wertsch{\"o}pfungskette zu reduzieren und die eigene Widerstandsf{\"a}higkeit gegen{\"u}ber Cyberbedrohungen systematisch zu erh{\"o}hen.}, language = {de} } @phdthesis{Alsarem2016, author = {Alsarem, Mazen}, title = {Semantic Snippets via Query-Biased Ranking of Linked Data Entities}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-3959}, school = {Universit{\"a}t Passau}, pages = {148 S.}, year = {2016}, abstract = {In our knowledge-driven society, the acquisition and the transfer of knowledge play a principal role. Web search engines are somehow tools for knowledge acquisition and transfer from the web to the user. The search engine results page (SERP) consists mainly of a list of links and snippets (excerpts from the results). The snippets are used to express, as efficiently as possible, the way a web page may be relevant to the query. As an extension of the existing web, the semantic web or "web 3.0" is designed to convert the presently available web of unstructured documents into a web of data consumable by both human and machines. The resulting web of data and the current web of documents coexist and interconnect via multiple mechanisms, such as the embedded structured data, or the automatic annotation. In this thesis, we introduce a new interactive artifact for the SERP: the "Semantic Snippet". Semantic Snippets rely on the coexistence of the two webs to facilitate the transfer of knowledge to the user thanks to a semantic contextualization of the user's information need. It makes apparent the relationships between the information need and the most relevant entities present in the web page. The generation of semantic snippets is mainly based on the automatic annotation of the LOD1's entities in web pages. The annotated entities have different level of impor- tance, usefulness and relevance. Even with state of the art solutions for the automatic annotations of LOD entities within web pages, there is still a lot of noise in the form of erroneous or off-topic annotations. Therefore, we propose a query-biased algorithm (LDRANK) for the ranking of these entities. LDRANK adopts a strategy based on the linear consensual combination of several sources of prior knowledge (any form of con- textual knowledge, like the textual descriptions for the nodes of the graph) to modify a PageRank-like algorithm. For generating semantic snippets, we use LDRANK to find the more relevant entities in the web page. Then, we use a supervised learning algorithm to link each selected entity to excerpts from the web page that highlight the relationship between the entity and the original information need. In order to evaluate our semantic snippets, we integrate them in ENsEN (Enhanced Search Engine), a software system that enhances the SERP with semantic snippets. Finally, we use crowdsourcing to evaluate the usefulness and the efficiency of ENsEN.}, subject = {World Wide Web 3.0}, language = {en} } @phdthesis{Alshawish2021, author = {Alshawish, Ali}, title = {Risk-based Security Management in Critical Infrastructure Organizations}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-10026}, school = {Universit{\"a}t Passau}, pages = {xii, 181 Seiten}, year = {2021}, abstract = {Critical infrastructure and contemporary business organizations are experiencing an ongoing paradigm shift of business towards more collaboration and agility. On the one hand, this shift seeks to enhance business efficiency, coordinate large-scale distribution operations, and manage complex supply chains. But, on the other hand, it makes traditional security practices such as firewalls and other perimeter defenses insufficient. Therefore, concerns over risks like terrorism, crime, and business revenue loss increasingly impose the need for enhancing and managing security within the boundaries of these systems so that unwanted incidents (e.g., potential intrusions) can still be detected with higher probabilities. To this end, critical infrastructure organizations step up their efforts to investigate new possibilities for actively engaging in situational awareness practices to ensure a high level of persistent monitoring as well as on-site observation. Compliance with security standards is necessary to ensure that organizations meet regulatory requirements mostly shaped by a set of best practices. Nevertheless, it does not necessarily result in a coherent security strategy that considers the different aims and practical constraints of each organization. In this regard, there is an increasingly growing demand for risk-based security management approaches that enable critical infrastructures to focus their efforts on mitigating the risks to which they are exposed. Broadly speaking, security management involves the identification, assessment, and evaluation of long-term (or overall) objectives and interests as well as the means of achieving them. Due to the critical role of such systems, their decision-makers tend to enhance the system resilience against very unpleasant outcomes and severe consequences. That is, they seek to avoid decision options associated with likely extreme risks in the first place. Practically speaking, this risk attitude can significantly influence the decision-making process in such critical organizations. Towards incorporating the aversion to extreme risks into security management decisions, this thesis investigates thoroughly the capabilities of a recently emerged theory of games with payoffs that are probability distributions. Unlike traditional optimization techniques, this theory provides an alternative decision technique that is more robust to extreme risks and uncertainty. Furthermore, this thesis proposes a new method that gives a decision maker more control over the decision-making process through defining loss regions with different importance levels according to people's risk attitudes. In this way, the static decision analysis used in the distribution-valued games is transformed into a dynamic process to adapt to different subjective risk attitudes or account for future changes in the decision caused by a learning process or other changes in the context. Throughout their different parts, this thesis shows how theoretical models, simulation, and risk assessment models can be combined into practical solutions. In this context, it deals with three facets of security management: allocating limited security resources, prioritizing security actions, and tweaking decision making. Finally, the author discusses experiences and limitations distilled from this research and from investigating the new theory of games, which can be taken into account in future approaches.}, subject = {Spieltheorie}, language = {en} } @phdthesis{Alyousef2021, author = {Alyousef, Ammar}, title = {E-Mobility Management: Towards a Grid-friendly Smart Charging Solution}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-9302}, school = {Universit{\"a}t Passau}, pages = {xvii, 159 Seiten}, year = {2021}, abstract = {Replacing fossil-fueled vehicles with Electric Vehicles (EVs) poses new challenges for power distribution networks. Specifically speaking, the electrification of the mobility sector relies on the ability to process and analyze information on when, where, for how long, or how fast charging processes will take place. Nevertheless, such kind of information is typically difficult to acquire or insufficiently predictable due to the dynamic nature of the system. Also, the increasing adoption rate of the renewable energy sources, specifically the domestic Photovoltaic (PV) systems, and the potentially associated grid defection scenarios will significantly impact the cost and efforts required to operate the grid in terms of power quality and demand-supply aspects. However, such emerging requirements have arguably not been taken into account when the distribution grid was built originally. Besides, expanding the distribution and transmission capacity is a very costly and lengthy process. Therefore, any proposed solution should be cost-effective as well as environment-, grid- and user-friendly. To this end, the advancements in Information and Communications Technology (ICT) are increasingly adopted and applied. This thesis addresses the rapidly growing EV sector and deals with the problems to overcome potential power quality degradation caused by the challenges mentioned above. Since time switch and radio ripple control as existing solutions in Germany are costly and neither very effective nor scalable as it requires hardware retrofitting of existing public Charging Stations (CSs), the primary focus of this work is the development of an appropriate, standards-based, scalable, and smart charging solution of EVs. Such a solution can, in turn, boost the usage of renewable energy by ensuring that the existing grid infrastructure can operate within its permissible limits while maintaining acceptable levels of power quality. This work introduces a new definition of the concept, "grid-friendly EV charging", where the power demand of a CS is adjusted depending on the real-time status of a power grid. In this regard, the conflicting concerns of stakeholders in an EV ecosystem are considered. For example, a Distribution System Operator (DSO) does not want to reveal a lot of technical details about the power grid or its status. Similarly, a Charging Service Provider (CSP) wants to keep its clients happy without sharing the details of its business model with others, namely, DSOs. For that sake, a distributed smart charging architecture is proposed in this thesis. It is event-driven and responds in nearly real-time to unforeseen and critical grid situations such as high/low voltage, congestion, phase unbalance, and harmonics. In that regard, the publish/subscribe messaging pattern, used as a part of the architecture, enables an efficient and well-performing communication scheme among the different components. Moreover, an indication mechanism about the different issues in a power grid is developed; it adopts the traffic light model. It works as a black box to separate smart controllers for each CS and configured only by the CSP. Smart chargers enable a smooth adjustment of the charging power to avoid drastic changes in the grid state. To that end, two types of intelligent controllers are developed and tested. While the first controller is inspired by the fuzzy logic, the second one is inspired by the slow-start mechanism used in TCP to control congestion in computer networks. A simulative approach is applied to evaluate the solution, thereby, a topology of a real low voltage grid with realistic load and generation profiles is used. Furthermore, a set of metrics is defined regarding the main concerns of stakeholders: voltage, overloading, fairness, the satisfaction of EV users and grid operator, as well as the grid-friendly behavior of a CS/ EV user. The evaluation shows that the solution is able to guarantee a safe operation of the grid. The proposed system can ensure a grid-friendly charging by sacrificing of a small portion of user satisfaction, that sacrifice of a user is awarded via a points-based reward system. Last but not least, the proposed distributed controllers are compared to two other controllers: (1) a decentralized controller based only on sensing the local voltage and (2) a very strict centralized controller focusing on grid-friendliness. The latter ensures proportional fairness among users regarding the objective function of the optimization problem solved in each simulation step. The distributed controllers are superior to the decentralized controller in terms of grid friendly and fairness and converge in general to the centralized one.}, subject = {Elektromobilit{\"a}t}, language = {en} } @article{AnagnostopoulosTeymuriSeratietal.2023, author = {Anagnostopoulos, Nikolaos Athanasios and Teymuri, Benyamin and Serati, Reza and Rasti, Mehdi}, title = {LP-MAB: Improving the Energy Efficiency of LoRaWAN Using a Reinforcement-Learning-Based Adaptive Configuration Algorithm}, series = {Sensors}, volume = {23}, journal = {Sensors}, number = {4}, editor = {Xie, Bin and Wang, Ning and Gu, Yi and Stefanidis, Angelos}, publisher = {MDPI}, address = {Basel, Switzerland}, issn = {1424-8220}, doi = {10.3390/s23042363}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-11853}, pages = {22 Seiten}, year = {2023}, abstract = {In the Internet of Things (IoT), Low-Power Wide-Area Networks (LPWANs) are designed to provide low energy consumption while maintaining a long communications' range for End Devices (EDs). LoRa is a communication protocol that can cover a wide range with low energy consumption. To evaluate the efficiency of the LoRa Wide-Area Network (LoRaWAN), three criteria can be considered, namely, the Packet Delivery Rate (PDR), Energy Consumption (EC), and coverage area. A set of transmission parameters have to be configured to establish a communication link. These parameters can affect the data rate, noise resistance, receiver sensitivity, and EC. The Adaptive Data Rate (ADR) algorithm is a mechanism to configure the transmission parameters of EDs aiming to improve the PDR. Therefore, we introduce a new algorithm using the Multi-Armed Bandit (MAB) technique, to configure the EDs' transmission parameters in a centralized manner on the Network Server (NS) side, while improving the EC, too. The performance of the proposed algorithm, the Low-Power Multi-Armed Bandit (LP-MAB), is evaluated through simulation results and is compared with other approaches in different scenarios. The simulation results indicate that the LP-MAB's EC outperforms other algorithms while maintaining a relatively high PDR in various circumstances.}, language = {en} } @phdthesis{Anderl2014, author = {Anderl, Eva}, title = {Three Essays on Analyzing and Managing Online Consumer Behavior}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus-27453}, school = {Universit{\"a}t Passau}, year = {2014}, abstract = {Over the last two decades, the Internet has fundamentally changed the ways firms and consumers interact. The ongoing evolution of the Internet-enabled market environment entails new challenges for marketing research and practice, including the emergence of innovative business models, a proliferation of marketing channels, and an unknown wealth of data. This dissertation addresses these issues in three individual essays. Study 1 focuses on business models offering services for free, which have become increasingly prevalent in the online sector. Offering services for free raises new questions for service providers as well as marketing researchers: How do customers of free e-services contribute value without paying? What are the nature and dynamics of nonmonetary value contributions by nonpaying customers? Based on a literature review and depth interviews with senior executives of free e-service providers, Study 1 presents a comprehensive overview of nonmonetary value contributions in the free e-service sector, including not only word of mouth, co-production, and network effects but also attention and data as two new dimensions, which have been disregarded in marketing research. By putting their findings in the context of existing literature on customer value and customer engagement, the authors do not only shed light on the complex processes of value creation in the emerging e-service industry but also advance marketing and service research in general. Studies 2 and 3 investigate the analysis of online multichannel consumer behavior in times of big data. Firms can choose from a plethora of channels to reach consumers on the Internet, such that consumers often use a number of different channels along the customer journey. While the unprecedented availability of individual-level data enables new insights into multichannel consumer behavior, it also makes high demands on the efficiency and scalability of research approaches. Study 2 addresses the challenge of attributing credit to different channels along the customer journey. Because advertisers often do not know to what degree each channel actually contributes to their marketing success, this attribution challenge is of great managerial interest, yet academic approaches to it have not found wide application in practice. To increase practical acceptance, Study 2 introduces a graph-based framework to analyze multichannel online customer path data as first- and higher-order Markov walks. According to a comprehensive set of criteria for attribution models, embracing both scientific rigor and practical applicability, four model variations are evaluated on four, large, real-world data sets from different industries. Results indicate substantial differences to existing heuristics such as "last click wins" and demonstrate that insights into channel effectiveness cannot be generalized from single data sets. The proposed framework offers support to practitioners by facilitating objective budget allocation and improving team decisions and allows for future applications such as real-time bidding. Study 3 investigates how channel usage along the customer journey facilitates inferences on underlying purchase decision processes. To handle increasing complexity and sparse data in online multichannel environments, the author presents a new categorization of online channels and tests the approach on two large clickstream data sets using a proportional hazard model with time-varying covariates. By categorizing channels along the dimensions of contact origin and branded versus generic usage, Study 3 finds meaningful interaction effects between contacts across channel types, corresponding to the theory of choice sets. Including interactions based on the proposed categorization significantly improves model fit and outperforms alternative specifications. The results will help retailers gain a better understanding of customers' decision-making progress in an online multichannel environment and help them develop individualized targeting approaches for real-time bidding. Using a variety of methods including qualitative interviews, Markov graphs, and survival models, this dissertation does not only advance knowledge on analyzing and managing online consumer behavior but also adds new perspectives to marketing and service research in general.}, subject = {Internet}, language = {en} } @article{AndraschkoDannerKreuzer2024, author = {Andraschko, Bernhard and Danner, Julian and Kreuzer, Martin}, title = {SAT Solving Using XOR-OR-AND Normal Forms}, series = {Mathematics in Computer Science (ISSN: 1661-8289)}, volume = {18}, journal = {Mathematics in Computer Science (ISSN: 1661-8289)}, number = {4}, publisher = {Springer International Publishing}, address = {Cham}, issn = {1661-8270}, doi = {10.1007/s11786-024-00594-x}, url = {http://nbn-resolving.de/urn:nbn:de:101:1-2502242130589.859216082138}, pages = {26 Seiten}, year = {2024}, abstract = {This paper introduces the XOR-OR-AND normal form (XNF) for logical formulas. It is a generalization of the well-known Conjunctive Normal Form (CNF) where literals are replaced by XORs of literals. As a first theoretic result, we show that every CNF formula is equisatisfiable to a formula in 2-XNF, i.e., a formula in XNF where each clause involves at most two XORs of literals. Subsequently, we present an algorithm which converts Boolean polynomials efficiently from their Algebraic Normal Form (ANF) to formulas in 2-XNF. Experiments with the cipher ASCON-128 show that cryptographic problems, which by design are based strongly on XOR-operations, can be represented using far fewer variables and clauses in 2-XNF than in CNF. In order to take advantage of this compact representation, new SAT solvers based on input formulas in 2-XNF need to be designed. By taking inspiration from graph-based 2-CNF SAT solving, we devise a new DPLL-based SAT solver for formulas in 2-XNF. Among others, we present advanced pre- and in-processing techniques. Finally, we give timings for random 2-XNF instances and instances related to key recovery attacks on round reduced ASCON-128, where our solver outperforms state-of-the-art alternative solving approaches.}, subject = {-}, language = {en} } @phdthesis{Ansah2021, author = {Ansah, Frimpong}, title = {Performance and optimization technologies for software defined industrial networks}, publisher = {Universit{\"a}t Passau}, address = {Passau}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-9002}, school = {Universit{\"a}t Passau}, pages = {xxi, 173 Seiten}, year = {2021}, abstract = {The concept of programmable networks is radically changing the way communication infrastructures are designed, integrated, and operated. Currently, the topic is spearheaded by concepts such as software-defined networking, forwarding and control element separation, and network function virtualization. Notably, software-defined networking has attracted significant attention in telecommunication and data centers and thus already in some production-grade networks. Despite the prevalence of software-defined networking in these domains, industrial networks are yet to see its benefits to encourage adoption. However, the misconceptions around the concept itself, the role of virtualization, and algorithms pose a significant obstacle. Furthermore, the desire to accommodate new services in the automation industry results in a pattern of constantly increasing complexity of industrial networks, which is compounded by the requirement to provide stringent deterministic service guarantees considering characteristically different applications and thus posing a significant challenge for management, configuration, and maintenance as existing solutions are architecturally inflexible. Therefore, the first contribution of this thesis addresses the misconceptions around software-defined networking by providing a comparative analysis of programmable network concepts, detailing where software-defined networks compare with other concepts and how its principles can be leveraged to evolve industrial networks. Armed with the fundamental principles of programmable networks, the second contribution identifies virtualization technologies and proposes novel algorithms to provide varied quality of service guarantees on converged time-sensitive Ethernet networks using software-defined networking concepts. Finally, a performance analysis of a software-defined hybrid deployment solution for control and management of time-sensitive Ethernet networks that integrates proposed novel algorithms is presented as an industrial use-case that enables industrial operators to harness the full potential of time-sensitive networks.}, language = {en} } @phdthesis{Apfler2018, author = {Apfler, Sabine}, title = {Erwerb mathematischer Kompetenzen in der Regelvolksschule}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-5593}, school = {Universit{\"a}t Passau}, pages = {447 Seiten}, year = {2018}, abstract = {Durch die Einf{\"u}hrung der Bildungsstandards{\"u}berpr{\"u}fungen erh{\"a}lt die Frage nach der Kompetenzentwicklung von Kindern einen zentralen Stellenwert in Bildungsangelegenheiten. Lehrkr{\"a}fte stehen dadurch vor der Aufgabe, ihren Unterricht diesbez{\"u}glich zu ver{\"a}ndern und L{\"o}sungen zu finden. Die Frage, ob der Einsatz der Montessorip{\"a}dagogik die Entwicklung mathematischer Kompetenzen positiv beeinflusst, wurde im Rahmen einer Dissertation diskutiert und empirisch erforscht werden. Der Arbeit liegt folgende Fragestellung zugrunde: Kann die Montessorip{\"a}dagogik dazu beitragen, dass Sch{\"u}lerinnen und Sch{\"u}ler in {\"o}sterreichischen Regelvolksschulen ein hohes Kompetenzniveau in Mathematik erreichen? Wie unterscheidet sich die Kompetenzentwicklung in Klassen, die von Lehrpersonen mit beziehungsweise ohne Montessoriausbildung unterrichtet werden? Bei der vorliegenden Studie handelt es sich um eine L{\"a}ngsschnittuntersuchung mit zwei Testzeitpunkten. Im Sinne einer summativen Evaluation wurden zu Beginn der Untersuchung die Basiskompetenzen mit dem „Entwicklungsorientierten Test zur Erfassung mathematischer Basiskompetenzen ab Schuleintritt (MBK 1+)" analysiert. Am Ende der dritten Schulstufe wurde eine abschließende Bewertung im Rahmen der IKM-Testung des BIFIE vorgenommen, um die Wirksamkeit des Einsatzes der Montessorimethode zu ermitteln. Untersucht wurden 14 Volksschulklassen, die entweder einer Untersuchungsgruppe oder einer Kontrollgruppe zugeordnet wurden. Die Klassen der Untersuchungsgruppe wurden von Lehrpersonen mit Montessori-Diplomausbildung unterrichtet, die Klassen der Kontrollgruppe von Lehrpersonen, die keine Montessoriausbildung absolviert haben. An der Studie nahmen 248 Sch{\"u}lerinnen und Sch{\"u}ler teil. Der Untersuchungszeitraum erstreckte sich {\"u}ber insgesamt drei Schuljahre. Die Ergebnisse der Studie zeigen Tendenzen, dass sich der Einsatz der Montessorip{\"a}dagogik positiv auf die Kompetenzentwicklung der Kinder im Bereich der Mathematik auswirkt.}, subject = {{\"O}sterreich}, language = {de} } @misc{AsenMolzPlank2016, author = {Asen-Molz, Katharina and Plank, Kathrin}, title = {P{\"a}dagogische Zertifikate im Lehramtsstudium zur individuellen Profilbildung}, doi = {10.15475/paradigma.2016.1.6}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-4325}, pages = {9}, year = {2016}, abstract = {Studierende sollen mittels gezielter und vertiefter Qualifizierung individuelle Profile herausbilden k{\"o}nnen. Deswegen wurden am Lehrstuhl f{\"u}r Grundschulp{\"a}dagogik und -didaktik der Universit{\"a}t Passau zum Wintersemester 2015/16 die beiden Schwerpunktprofile „Begabungsf{\"o}rderung und kindzentriertes Unterrichten" und „Inklusion und inklusive Schulgestaltung" implementiert. Im Folgenden werden die konzeptionellen {\"U}berlegungen und die Durchf{\"u}hrung dieser Schwerpunktprofilsetzung erl{\"a}utert.}, subject = {Universit{\"a}t Passau}, language = {de} } @phdthesis{Asjoma2021, author = {Asjoma, Jan}, title = {Die EU-Wirtschaftsordnung im Lichte wirtschaftssystemischer Einordnung und volkswirtschaftlicher Entwicklung}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-10318}, school = {Universit{\"a}t Passau}, pages = {xii, 411 Seiten}, year = {2021}, abstract = {Die Arbeit unternimmt eine begriffshistorische Einordnung des Wirtschaftsverfassungsbegriffs von 1924 bis 2017 aus Sicht der deutschen, vor allem rechtswissenschaftlichen Literatur und den damit verbundenen anhaltenden Deutungsschwierigkeiten. Im Hauptteil wird die EU-Wirtschaftsordnung in Gestalt von Prim{\"a}rrecht, Sekund{\"a}rrecht sowie der bedeutendsten (EU-)Kommissionspraxis in Sachen Regulierung und finanzieller Mittelvergabe auf deren wirtschaftssystemischen Gehalt untersucht, mithin inwieweit die EU-Politik aus ordnungspolitischer Sicht als liberal/liberalisierend, b{\"u}rokraitsch-neutral oder als interventionistisch anzusehen ist. Dabei wird ein Schwerpunkt bei der bisher wirtschaftssystemisch wenig beleuchteten Geldpolitik am Beispiel der EWU gesetzt. Zuletzt wird die Entwicklung mitgliedsstaatlicher Volkswirtschaften anhand {\"u}blicher Kennziffern der volkswirtschaftlichen Gesamtrechnungen im Zeitraum von 1997 bis 2018 im direkten Vergleich dargestellt. Ausgew{\"a}hlte Problemkreise der {\"o}konomischen Analyse wurden vertieft, darunter die Verteilung der Geldsch{\"o}pfung im Euroraum (nach Eurozonen-Mitgliedsstaaten) sowie die Bedeutung anhaltender Zahlungsbilanzungleichgewichte.}, language = {de} } @phdthesis{Audebert2000, author = {Audebert, Fritz}, title = {Faktor Zeit: Internationale Fernsehwerbung im Spannungsfeld von Kultur und {\"O}konomie}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus-139}, school = {Universit{\"a}t Passau}, year = {2000}, abstract = {Die Arbeit befasst sich mit dem Faktor Zeit in der internationalen Fernsehwerbung und seinen Kulturraum bedingten Unterschiede. In keinem anderen Medium spielen marktwirtschaftliche Regeln und Kontrollinstrumente eine so entscheidende Rolle wie in der Fernsehwerbung. Bei Kulturraum-{\"o}konomisch optimalem Einsatz von Werbebudget k{\"o}nnen zuk{\"u}nftig große Summen Geld gespart werden. Insbesondere im zeitlich bedingten suboptimalen Einsatz von Werbegeldern liegt großes Verbesserungspotential.}, subject = {Werbesendung / Fernsehsendung}, language = {de} } @phdthesis{Auer2014, author = {Auer, Christopher}, title = {Planar Graphs and their Duals on Cylinder Surfaces}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus-27430}, school = {Universit{\"a}t Passau}, year = {2014}, abstract = {In this thesis, we investigates plane drawings of undirected and directed graphs on cylinder surfaces. In the case of undirected graphs, the vertices are positioned on a line that is parallel to the cylinder's axis and the edge curves must not intersect this line. We show that a plane drawing is possible if and only if the graph is a double-ended queue (deque) graph, i. e., the vertices of the graph can be processed according to a linear order and the edges correspond to items in the deque inserted and removed at their end vertices. A surprising consequence resulting from these observations is that the deque characterizes planar graphs with a Hamiltonian path. This result extends the known characterization of planar graphs with a Hamiltonian cycle by two stacks. By these insights, we also obtain a new characterization of queue graphs and their duals. We also consider the complexity of deciding whether a graph is a deque graph and prove that it is NP-complete. By introducing a split operation, we obtain the splittable deque and show that it characterizes planarity. For the proof, we devise an algorithm that uses the splittable deque to test whether a rotation system is planar. In the case of directed graphs, we study upward plane drawings where the edge curves follow the direction of the cylinder's axis (standing upward planarity; SUP) or they wind around the axis (rolling upward planarity; RUP). We characterize RUP graphs by means of their duals and show that RUP and SUP swap their roles when considering a graph and its dual. There is a physical interpretation underlying this characterization: A SUP graph is to its RUP dual graph as electric current passing through a conductor to the magnetic field surrounding the conductor. Whereas testing whether a graph is RUP is NP-hard in general [Bra14], for directed graphs without sources and sink, we develop a linear-time recognition algorithm that is based on our dual graph characterization of RUP graphs.}, subject = {Planarer Graph}, language = {en} } @phdthesis{Auer2024, author = {Auer, Michael}, title = {Improving Automated Android Test Generation}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-14955}, school = {Universit{\"a}t Passau}, pages = {x, 140 Seiten}, year = {2024}, abstract = {Mobile apps are nowadays the preferred means to accomplish ubiquitous tasks like messaging, e-commerce and even playing games. Often, there exist multiple apps for the same purpose, and it is the choice of the end user to pick an appropriate app. Apps that behave unexpected, e.g., crash frequently, are sooner or later replaced, which isundesirable for the companies developing such apps. Thus, it is essential to tests apps properly before they are released onto the market. However, testing manually is often not only too cost-intensive but also too time-consuming in the short development phase, thus an automated solution is preferred. Testing mobile apps automatically received increased attention in the last decade from primarily people in academia, and several testing techniques evolved. One technique that yielded promising results, especially in different domains, is search-based software testing in which a metaheuristic, e.g., a genetic algorithm, is applied to solve an optimisation problem, e.g., test generation. A main objective of test generation is to produce tests that reveal as many faults as possible. This in turn requires the generation of tests that deeply explore the tested app. The core metric to quantify how much code tests cover is the measurement of code coverage, which can be computed at different levels of granularity ranging from determining the fraction of covered activities to a very fine-grained measurement that calculates the percentage of covered lines. This coverage information is then often used to guide the search of the employed metaheuristic. However, current automated test generation approaches produce tests with a rather low code coverage. Thus, a substantial part of tested apps remains unexplored, which in turn misses revealing deeply residing faults. We identified three core issues that are directly related to the generation of low-coverage tests. First, the applicability of current test generators is often limited. This comprises the fact that current state-of-the-art code coverage tools are incapable of instrumenting a substantial number of apps and consequently, test generators cannot utilise detailed coverage information during exploration. In addition, test generators are often only equipped with a primitive set of actions that are insufficient to simulate system events and complex user inputs. Second, the test execution is extremely time-consuming. This includes among other things the overhead associated with executing individual actions, intermediate restart operations as well as fitness evaluations. Since search-based algorithms require a substantial number of test executions to play out their strengths, the slow test execution impedes the effectiveness of the search. Third, the guidance offered by search-based algorithms is often hampered by applying inadequate fitness functions or by using non-representation-specific variation operators. In this thesis we address the problem of low-coverage tests in the Android domain by proposing several enhancements for the three identified core issues. Concerning the applicability problem, we provide the implementation of a robust code coverage tool that is capable of measuring coverage at different levels of granularity and requires no access to the source code. We also propose to include actions that can simulate system events as well as complex user inputs. Regarding the performance issue, we suggest the integration of a surrogate model that is capable of predicting the outcome of individual actions or complete tests over time in order to reduce the overall test execution costs. With respect to the lack of guidance offered by traditional search-based algorithms, we suggest alternative search strategies. In the case of a deceptive fitness landscape, we propose using novelty search algorithms. Alternatively, we suggest utilising estimation of distribution algorithms that require no crossover or mutation perators to sample new tests. While all those enhancements had a positive impact on the Android test generation process, the individual empirical studies highlighted that further research is necessary to unleash the full power of the proposed search-based algorithms. In particular, exploring complex user interfaces meaningfully requires more attention whether by introducing additional actions or by extracting valuable hints to infer reasonable text inputs. In addition, the guidance offered by fitness functions is often limited because they are either designed too coarse at all or do not accurately reflect the search objectives.}, language = {en} } @phdthesis{Aufenvenne2022, author = {Aufenvenne, Philipp}, title = {Looking at what Geographers do - Empirische Beitr{\"a}ge zur Wissenschaftsbeobachtung in der Geographie}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-12764}, school = {Universit{\"a}t Passau}, pages = {VII, 214 Seiten}, year = {2022}, abstract = {The research interest of this doctoral thesis addresses the academic practice of German-speaking geography. It is thus both a "meta-geographical" thesis in the sense of disciplinary science research and a social-geographical thesis that examines how scientists interact with each other as social actors in the academic field. In this dissertation, a total of five scientific articles are presented. All contributions examine German-language geography from a scientometric perspective. The unifying aspect of this work is not the one major research question, but the research object and the methodological perspective taken. The work is divided into two parts: Based on bibliometric data research and network analysis, the first part is dealing with the question of the unity of geography (papers 1-3) and paradigm evolution exemplified by the new cultural geography (paper 4). The second part deals with gender inequalities in geography. Here, one scientific article (paper 5) is presented and put into context. The focus is on gender differences in scientific practices at geographic conferences.}, subject = {Netzwerkanalyse }, language = {de} } @phdthesis{Augsten2002, author = {Augsten, Frank}, title = {Zur Begrenzung der Staatsverschuldung im f{\"o}deralen Staat}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus-362}, school = {Universit{\"a}t Passau}, year = {2002}, abstract = {Seit geraumer Zeit wird den {\"o}ffentlichen Haushalten in der Bundesrepublik Deutschland und hierbei insbesondere den Haushaltsdefiziten sowie dem Schuldenstand eine große Aufmerksamkeit zuteil. Dazu beigetragen hat nicht nur der enorme Anstieg der Schulden der {\"o}ffentlichen Hand und die damit einhergehende Zinslast nach der Wiedervereinigung. Auch die Verpflichtung Deutschlands, als Mitglied der Europ{\"a}ischen W{\"a}hrungsunion {\"u}berm{\"a}ßige {\"o}ffentliche Defizite zu vermeiden und im Rahmen des europ{\"a}ischen Stabilit{\"a}ts- und Wachstumspakts in den kommenden Jahren sogar einen ausgeglichenen Staatshaushalt auszuweisen, l{\"a}sst sich als Ursache f{\"u}r diese Entwicklung ausmachen. Vor dem Hintergrund der Frage, wie es zuk{\"u}nftig gelingen kann, das gesamtstaatliche Defizit und damit auch den Anstieg des Schuldenstandes des Staates zu begrenzen, werden zun{\"a}chst auf der Grundlage der langfristigen Auswirkungen der Staatsverschuldung auf die gesamtwirtschaftliche Entwicklung die Grenzen der Staatsverschuldung herausgearbeitet. Daraufhin werden die Grenzen der Staatsverschuldung aus {\"o}konomischer Sicht mit jenen Grenzen der Staatsverschuldung verglichen, die sich aus dem Grundgesetz ergeben. In diesem Zusammenhang wird dargelegt, dass die institutionellen Grenzen der Staatsverschuldung zum einen weiter gefasst sind, als dies aus {\"o}konomischer Sicht sinnvoll ist. Zum anderen wird aufgezeigt, dass sich aus der Finanzverfassung f{\"u}r die Entscheidungstr{\"a}ger dar{\"u}ber hinaus Anreize ergeben, den verfassungsrechtlichen Rahmen in einem Umfang in Anspruch zu nehmen, der zu einem {\"U}berschreiten der {\"o}konomischen Grenzen der Staatsverschuldung f{\"u}hrt. Vor diesem Hintergrund wird ein Vorschlag zur Reform der Finanzverfassung vorgestellt, der den {\"o}konomischen Anforderungen besser Rechnung tr{\"a}gt als die derzeitigen Regelungen und der gleichzeitig mit der bundesstaatlichen Ordnung des Grundgesetzes vereinbar ist.}, subject = {{\"O}ffentliche Schulden}, language = {de} } @article{AugstenGlassnerRall2022, author = {Augsten, Pauline and Glassner, Sebastian and Rall, Jenni}, title = {The Myth of Responsibility: Colonial Cruelties and Silence in German Political Discourse}, series = {Global Studies Quarterly}, journal = {Global Studies Quarterly}, doi = {10.1093/isagsq/ksab040}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-10437}, pages = {1 -- 12}, year = {2022}, abstract = {Germany is considered a role model for dealing with past mass atrocities. In particular, the social reappraisal of the Holocaust is emblematic of this. However, when considering the genocide on the Herero and Nama in present-day Namibia, it is puzzling that an official recognition was only pronounced after almost 120 years, in May 2021. For a long time, silence surrounded this colonial cruelty in German political discourse. Although the discourse on German responsibility toward Namibia emerged after the end of World War II, it initially appeared detached from the genocide. That silence on colonial atrocities is to be considered a cruelty itself. Studies on silence have been expanding and becoming richer. Building on these works, the paper sets two goals: First, it advances the theorization of silence by producing a new typology, which is then integrated into discourse-bound identity theory. Second, it applies this theory to the analysis of the silencing and later acknowledging of the genocide on the Herero and Nama by German political elites. To this end, Bundestag debates, official documents, and statements by relevant political actors are analyzed in the period from 1980 to 2021. The results reveal the dynamics between hegemonic and counter-hegemonic discursive formations, how those are shifting in a period of 40 years, and what role silence plays in it. Beyond our emphasis on the genocide on the Herero and Nama, our findings might benefit future studies as the approach proposed in this paper can make silence a tangible research object for global studies.}, language = {en} } @phdthesis{Awwad2018, author = {Awwad, Tarek}, title = {Context-Aware Worker Selection For Efficient Quality Control In Crowdsourcing}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-7409}, school = {Universit{\"a}t Passau}, pages = {106 Seiten}, year = {2018}, abstract = {In the last decade, crowdsourcing has proved its ability to address large scale data collection tasks, such as labeling large data sets, at a low cost and in a short time. However, the performance and behavior variability between workers as well as the variability in task designs and contents, induce an unevenness in the quality of the produced contributions and, thus, in the final output quality. In order to maintain the effectiveness of crowdsourcing, it is crucial to control the quality of the contributions. Furthermore, maintaining the efficiency of crowdsourcing requires the time and cost overhead related to the quality control to be at its lowest. While effective, current quality control techniques such as contribution aggregation, worker selection, context-specific reputation systems, and multi-step workflows, suffer from fairly high time and budget overheads and from their dependency on prior knowledge about individual workers. In this thesis, we address this challenge by leveraging the similarity between completed and incoming tasks as well as the correlation between the worker declarative profiles and their performance in previous tasks in order to perform an efficient task-aware worker selection. To this end, we propose CAWS (Context AwareWorker Selection) method which operates in two phases; in an offline phase, completed tasks are clustered into homogeneous groups for each of which the correlation with the workers declarative profile is learned. Then, in the online phase, incoming tasks are matched to one of the existing clusters and the correspondent, previously inferred profile model is used to select the most reliable online workers for the given task. Using declarative profiles helps eliminate any probing process, which reduces the time and the budget while maintaining the crowdsourcing quality. Furthermore, the set of completed tasks, when compared to a probing task split, provides a larger corpus from which a more precise profile model can be learned. This translates to a better selection quality, especially for harder tasks. In order to evaluate CAWS, we introduce CrowdED (Crowdsourcing Evaluation Dataset), a rich dataset to evaluate quality control methods and quality-driven task vectorization and clustering. The generation of CrowdED relies on a constrained sampling approach that allows to produce a task corpus which respects both, the budget and type constraints. Beside helping in evaluating CAWS, and through its generality and richness, CrowdED helps in plugging the benchmarking gap present in the crowdsourcing quality control community. Using CrowdED, we evaluate the performance of CAWS in terms of the quality of the worker selection and in terms of the achieved time and budget reduction. Results shows the following: first, automatic grouping is able to achieve a learning quality similar to job-based grouping. And second, CAWS is able to outperform the state-of-the-art profile-based worker selection when it comes to quality. This is especially true when strong budget and time constraints are present on the requester side. Finally, we complement our work by a software contribution consisting of an open source framework called CREX (CReate Enrich eXtend). CREX allows the creation, the extension and the enrichment of crowdsourcing datasets. It provides the tools to vectorize, cluster and sample a task corpus to produce constrained task sets and to automatically generate custom crowdsourcing campaign sites.}, subject = {Qualit{\"a}tssicherung}, language = {en} } @techreport{AzcuyBecquerHeinrich2023, author = {Azcuy Becquer, Claudia and Heinrich, Horst-Alfred}, title = {Data documentation on history visualisations on the covers of all issues of Der Spiegel between 1965 and 2021}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-12678}, pages = {126 Seiten}, year = {2023}, abstract = {To answer the research question, all SPIEGEL covers from 1965 to 2021 were examined for a reference to history topics. The report documents the assignments of the 533 covers recorded to the categories of history narrative, politics of memory and politics of the past. Main article: https://doi.org/10.3167/jemms.2023.150107}, language = {en} } @phdthesis{Baak2025, author = {Baak, Werner}, title = {Advanced Ordered Weighted Averaging Methods in Robust Optimization}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-15879}, school = {Universit{\"a}t Passau}, pages = {viii, 88 Seiten}, year = {2025}, abstract = {In decision-making under uncertainty, robust optimization is a critical tool across various fields, providing solutions that perform effectively across a range of scenarios where precise probabilities are unavailable or unreliable. Traditional approaches, such as min-max and min-max regret, focus on minimizing the worst-case outcomes and worst-case regret, respectively, often resulting in highly conservative solutions. To address this limitation, this dissertation investigates the Ordered Weighted Averaging (OWA) operator, which offers a flexible framework for aggregating outcomes according to varying risk preferences, from risk-averse to risk-neutral, encompassing traditional robust approaches as special cases. This work is organized around three primary contributions that expand the application and understanding of OWA in robust optimization. The first contribution develops a preference elicitation framework for OWA weights, enabling decision-makers to derive weighting schemes based on observed historical decisions, thereby aligning aggregation strategies with specific risk attitudes. The second contribution introduces a novel variant of OWA for robust optimization, integrating OWA into a regret minimization framework to generalize both robust min-max and min-max regret approaches. This model is complemented by new complexity results, including insights into the inapproximability and approximability of OWA regret, providing stronger approximation bounds that asymptotically improve on previously established results for classic OWA models. These advancements position the OWA regret model as a powerful alternative to min-max regret, offering a more adaptable approach to risk-sensitive decision-making. The third contribution addresses interval uncertainty, extending the OWA framework to scenarios where outcomes are represented as bounded intervals instead of discrete points. This interval-based OWA model accommodates real-world decision-making needs, where scenario data are uncertain or costly to specify. By using Value-at-Risk (VaR) in our definition, we provide a natural way to handle continuous ranges of uncertainty while maintaining computational tractability for large-scale problems. Together, these contributions advance both the theoretical and practical applications of OWA in decision making, establishing OWA-based methods as versatile tools for addressing complex uncertainties across a variety of decision-making environments.}, language = {en} } @article{Bach2024, author = {Bach, Maurizio}, title = {Effektiveres Pandemiemanagement durch sozialwissenschaftliche Politikberatung? Ein kritischer Kommentar zu J{\"o}rn Knoblochs Beitrag in Heft 4/2023}, series = {Berliner Journal f{\"u}r Soziologie (ISSN: 1862-2593)}, volume = {34}, journal = {Berliner Journal f{\"u}r Soziologie (ISSN: 1862-2593)}, number = {3}, publisher = {Springer Fachmedien}, address = {Wiesbaden}, issn = {0863-1808}, doi = {10.1007/s11609-024-00535-2}, url = {http://nbn-resolving.de/urn:nbn:de:101:1-2412102126103.260519352471}, pages = {443 -- 460}, year = {2024}, abstract = {Der Kommentar setzt sich kritisch mit J{\"o}rn Knoblochs Analyse des Corona-Pandemiemanagements in Deutschland auseinander. Er hinterfragt die Behauptung Knoblochs, durch eine st{\"a}rkere Ber{\"u}cksichtigung von Sozialwissenschaftlern in den einschl{\"a}gigen Beratungsgremien h{\"a}tte eine effektivere Krisenbew{\"a}ltigung erreicht werden k{\"o}nnen. Der Beitrag fokussiert zum einen die strukturellen epistemischen Grenzen sowohl der biomedizinischen Wissenschaften als auch der empirischen Sozialforschung. Zum anderen beleuchtet er die Eigenlogik politischer Entscheidungsprozesse, die durch die Notwendigkeit der Unsicherheitsabsorption und Systemstabilisierung gepr{\"a}gt sind und gegen{\"u}ber externen Einfl{\"u}ssen als relativ immun erscheinen. Der Beitrag pl{\"a}diert f{\"u}r eine differenzierte Betrachtung der Schnittstelle zwischen wissenschaftlicher Beratung und politischer Praxis und mahnt eine kritische Reflexion der Rolle und der Grenzen der wissenschaftsgest{\"u}tzten Politikberatung an.}, subject = {-}, language = {de} } @phdthesis{Bachl2001, author = {Bachl, Sabine}, title = {Isomorphe Subgraphen und deren Anwendung beim Zeichnen von Graphen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus-149}, school = {Universit{\"a}t Passau}, year = {2001}, abstract = {In der Arbeit wird der Begriff der Isomorphen Subgraphen definiert. Anschließend werden theoretische und praktische Ergebnisse bei der Erkennung Isomorpher Graphen er{\"o}rtert.}, subject = {Isomorpher Teilgraph}, language = {de} } @phdthesis{Bachl2003, author = {Bachl, Walter}, title = {Interaktives orthogonales Zeichnen von planaren Graphen}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus-392}, school = {Universit{\"a}t Passau}, year = {2003}, abstract = {Die Arbeit besch{\"a}ftigt sich mit dem automatischen Zeichnen von Graphen. Hier wird ein interaktiver Ansatz untersucht, bei dem der Graph mit einer Menge von Operationen Schritt f{\"u}r Schritt aufgebaut wird. Der Zielgraph und die Einf{\"u}gereihenfolge sind dabei nicht fest vorgegeben, sondern werden vom Benutzer bestimmt. In der Arbeit wird vor allem ein Szenario f{\"u}r zweifach zusammenh{\"a}ngende Graphen untersucht und ein f{\"u}r diese Zwecke passendes Zeichenmodell entwickelt. Dieser Ansatz wird dann um verschiedene Varianten erweitert. Außerdem wird gezeigt, dass das fl{\"a}chenminimale Zeichnen in dem neu entwickelten Zeichenmodell NP-vollst{\"a}ndig ist.}, subject = {Graphenzeichnen}, language = {de} } @phdthesis{Bachmaier2004, author = {Bachmaier, Christian}, title = {Circle Planarity of Level Graphs}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus-385}, school = {Universit{\"a}t Passau}, year = {2004}, abstract = {In this dissertation we generalise the notion of level planar graphs in two directions: track planarity and radial planarity. Our main results are linear time algorithms both for the planarity test and for the computation of an embedding, and thus a drawing. Our algorithms use and generalise PQ-trees, which are a data structure for efficient planarity tests.}, subject = {Graphentheorie}, language = {en} } @phdthesis{Bachmann2005, author = {Bachmann, Ralf}, title = {Die Straubinger Volksschullehrer und ihre Geistliche Schulaufsicht (1790-1918)}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus-693}, school = {Universit{\"a}t Passau}, year = {2005}, abstract = {1790 hatte die Stadt Straubing auf Anordnung der Regierung das Volksschulwesen im Stadtgebiet zu organisieren und zu {\"u}berwachen. Aus den existierenden drei Winkelschulen entwickelten sich bis zum Ende des Ersten Weltkriegs f{\"u}nf Elementarschulen: Die Knaben-schule zu St. Jakob, die M{\"a}dchenschule St. Jakob bei den Ursulinen, die Knaben- und die M{\"a}dchenschule zu St. Peter sowie die Protestantische Schule. Die vorliegende Dissertation will zun{\"a}chst die Entwicklungsgeschichte dieser f{\"u}nf Schulen verfolgt und einen Blick auf die wechselnden Schulh{\"a}user und die stetig wachsenden Kollegien werfen. Im Anhang befinden sich Schematismen f{\"u}r insgesamt fast 300 nachgewiesene geistliche und weltliche P{\"a}dagogen. In dem Streifzug durch die Geschichte wird auf dem Hintergrund der Stadtentwicklung das Schulleben fr{\"u}herer Tage lebendig, wobei auch einige herausragende Lehrerpers{\"o}nlichkeiten in Leben und beruflichen Wirken genauer vorgestellt werden. Im Zentrum des zweiten Teiles steht die Beaufsichtigung dieser Schulen. Unmittelbarer Vorgesetzter war der Lokalschulinspektor. Insgesamt 23, bislang weitgehend unbekannte Stadtpfarrer von St. Jakob und St. Peter waren in diesem Amt t{\"a}tig und hatten als Geistliche die fachliche Leitung inne. Sie trugen mittels Visitation und {\"o}ffentlicher Schulpr{\"u}fung zur Qualit{\"a}tssicherung bei. In Fragen der Organisation dagegen war die Stadtschulenkommission mit dem B{\"u}rgermeister an der Spitze zust{\"a}ndig. In dem Spannungsfeld zwischen Geistlichen, Stadtinteressen und P{\"a}dagogik waren Alltagsprobleme wie z.B. Schulvers{\"a}umnisse ebenso zu l{\"o}sen wie Fragen im Bereich von Fortbildung und Didaktik. So wurde 1843 ein schulspezifischer Lehrplan entwickelt, der in ganz Altbayern Vorbildfunktion hatte. Mit Abschluss des Jahres 1918 aber wurde die Geistliche Schulaufsicht nach langem und erbittert gef{\"u}hrtem Kampf auch im Volksschulwesen durch die Fachaufsicht der Schulr{\"a}te abgel{\"o}st.}, subject = {Volkssch{\"u}ler}, language = {de} } @phdthesis{Bajec2008, author = {Bajec, Luka}, title = {Three Essays On The Bank Lending Channel}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus-12827}, school = {Universit{\"a}t Passau}, year = {2008}, abstract = {Monetary policy is commonly assumed to impact on commodity demand via relative prices. The bank lending channel (BLC) proposes an additional effect via the quantity of loans. This has found its way into economic textbooks, although it remains empirically controversial. I present various theoretical criticisms of the BLC and its building block, the formal model by Bernanke and Blinder (1988). This model operates with lopsided loan demand, money demand and money supply functions. The logic of the BLC is valid for individual investors who are affected by a cut in bank loans. For a whole sector with a given level of interest rates a reduction of loans does not however dry up investment, but only the holding of money. Since 1988 academics have been using model by Bernanke and Blinder as a work horse to empirically address the question of the quantitative relevance of the BLC. Cecchetti (1995) und Hubbard (1995) summarize the overall evolution of the controversial debate up to then. The data used for the research is mainly from the United States. In this literature review, I mainly focus on the next and more recent cohort of empirical investigations on the BLC in Europe that follow papers by Kashyap and Stein (1995, 2000) and Kishan and Opiela (2000) on U.S. transmission mechanisms. It is crucial that these authors are the first to address the question using individual bank balance sheet data for the U.S. Until now, empirical research has produced largely inconsistent results. This is more revealing as many of these investigations have deficiencies in controlling for other transmission channels that relate to relative prices. The debate on how monetary policy works has not ended: the BLC, which stresses the importance of potential changes in the supply of loans as a result of monetary policy, and its subsequent impact on aggregate demand, became prominent recently, but the concluding empirical evidence is absent. I attempt to contribute to this debate by conducting a cross-section and panel data analysis of developed and developing countries and by choosing the availability of bank loans as a dependent variable. The latter circumvents identification problems that appear when analyzing the response of aggregated bank loans to monetary policy changes. This evidence finds no support for the prediction of the BLC that there is an additional channel of monetary transmission mechanism.}, subject = {Bankkredit}, language = {en} } @misc{Barbato2015, author = {Barbato, Mariano}, title = {Posts{\"a}kulare Weltpolitik}, editor = {Barbato, Mariano and Marfeld, Sarah}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-5564}, pages = {190 Seiten}, year = {2015}, abstract = {Der Sammelband analysiert den Einfluss von Religion in der Weltpolitik an Fallbeispielen zwischen Internationalen Beziehungen, Welt{\"o}ffentlichkeit, L{\"a}nderstudien und Europ{\"a}ischer Integration. Der posts{\"a}kulare Ansatz von J{\"u}rgen Habermas wird auf sein globales Potential an der Schnittstelle von Außen- und Innenpolitik {\"u}berpr{\"u}ft und weiterentwickelt.}, subject = {Religion}, language = {de} } @book{Barbato2023, author = {Barbato, Mariano}, title = {Regieren durch Argumentieren?}, volume = {2023}, edition = {2., aktualisierte und erweiterte Auflage}, publisher = {Nomos}, address = {Baden-Baden}, isbn = {978-3-7489-1490-7}, doi = {10.5771/9783748914907}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-12899}, publisher = {Universit{\"a}t Passau}, pages = {316 Seiten}, year = {2023}, abstract = {Macht und Legitimit{\"a}t der europ{\"a}ischen Argumentationszusammenh{\"a}nge haben gelitten. Dennoch z{\"a}hlen Interessen und Ideen in Europa weiter nur dann, wenn sie als Argumente vorgebracht werden. Jenseits des Argumentierens ist Europa unregierbar. Zwei Fragen stehen im Zentrum des Bandes: Was meint Argumentieren? Wie lauten die Argumente Europas? Mit Aristoteles und Wittgenstein entwickelt der erste Teil eine Methode zur Narration politischer Argumentationszusammenh{\"a}nge. Der zweite Teil legt eine historische Sprachspieltopik von der Montanunion bis zum Green New Deal vor. Das Buch ist gleichermaßen interessant f{\"u}r alle mit praktischem Interesse an der EU wie f{\"u}r alle mit sprachphilosophischem Interesse an der Politikwissenschaft.}, language = {de} } @article{Basmadjian2019, author = {Basmadjian, Robert}, title = {Flexibility-Based Energy and Demand Management in Data Centers}, series = {Energies}, volume = {2019}, journal = {Energies}, number = {12}, publisher = {MDPI}, address = {Basel}, doi = {10.3390/en12173301}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-9251}, pages = {1 -- 22}, year = {2019}, abstract = {The power demand (kW) and energy consumption (kWh) of data centers were augmenteddrastically due to the increased communication and computation needs of IT services. Leveragingdemand and energy management within data centers is a necessity. Thanks to the automated ICTinfrastructure empowered by the IoT technology, such types of management are becoming more feasiblethan ever. In this paper, we look at management from two different perspectives: (1) minimization of theoverall energy consumption and (2) reduction of peak power demand during demand-response periods.Both perspectives have a positive impact on total cost of ownership for data centers. We exhaustivelyreviewed the potential mechanisms in data centers that provided flexibilities together with flexiblecontracts such as green service level and supply-demand agreements. We extended state-of-the-artby introducing the methodological building blocks and foundations of management systems for theabove mentioned two perspectives. We validated our results by conducting experiments on a lab-gradescale cloud computing data center at the premises of HPE in Milano. The obtained results support thetheoretical model, by highlighting the excellent potential of flexible service level agreements in Green IT:33\% of overall energy savings and 50\% of power demand reduction during demand-response periods inthe case of data center federation.}, language = {en} } @article{BauerHauptLinner2024, author = {Bauer, Ida and Haupt, Harry and Linner, Stefan}, title = {Pinball boosting of regression quantiles}, series = {Computational Statistics \& Data Analysis (Online ISSN: 1872-7352)}, volume = {2024}, journal = {Computational Statistics \& Data Analysis (Online ISSN: 1872-7352)}, number = {200}, publisher = {Elsevier}, address = {Amsterdam}, doi = {10.1016/j.csda.2024.108027}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-18850}, pages = {12 Seiten}, year = {2024}, abstract = {An algorithm for boosting regression quantiles using asymmetric least absolute deviations, better known as pinball loss, is proposed. Existing approaches for boosting regression quantiles are essentially equal to least squares boosting of regression means with the single difference that their working residuals are based on pinball loss. All steps of our boosting algorithm are embedded in the well-established framework of quantile regression, and its main components - sequential base learning, fitting, and updating - are based on consistent scoring rules for regression quantiles. The Monte Carlo simulations performed indicate that the pinball boosting algorithm is competitive with existing approaches for boosting regression quantiles in terms of estimation accuracy and variable selection, and that its application to the study of regression quantiles of hedonic price functions allows the estimation of previously infeasible high-dimensional specifications.}, language = {en} } @phdthesis{Bauer2022, author = {Bauer, Judith}, title = {Judas Iskariot - Eine narrative Analyse der Figur im Matth{\"a}usevangelium}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-10529}, school = {Universit{\"a}t Passau}, pages = {262 Seiten}, year = {2022}, abstract = {Die Studie betrachtet das Matth{\"a}usevangelium als zusammenh{\"a}ngende und durchkomponierte Erz{\"a}hlung, um anhand einer narrativen Analyse eine Charakterisierung der Judasfigur vorzunehmen. Dieser Ansatz ber{\"u}cksichtigt, wie sich die Figur in das Gesamtkonzept des Textes einf{\"u}gt und welches Erz{\"a}hlinteresse mit ihr verfolgt wird. Diese synchrone, zusammenh{\"a}ngende Lesart erhellt: Judas ist im Matth{\"a}usevangelium keine rein historische Figur, sondern seine Darstellung hat eine bestimmte Funktion, die mit dem historischen Kontext, der Pragmatik und der theologischen Konzeption des gesamten Textes zu tun hat. Das Matth{\"a}usevangelium behandelt das Thema der Sch{\"u}lerschaft und Nachfolge Jesu, wobei die beiden Pole „Mit-Jesus-Sein" und „Wenigvertrauen" eine zentrale Rolle spielen. Vor diesem Horizont steht Judas nicht f{\"u}r den „B{\"o}sen", von dem sich die Leserinnen und Leser abgrenzen sollten, sondern er ist Teil der Nachfolgegemeinschaft. Sein Scheitern k{\"o}nnte im Grunde jeden treffen oder anders gesagt: Jeder k{\"o}nnte Judas sein. Zugleich bietet der Text Strategien an, wie mit derartigem Versagen umzugehen ist: Scheitern darf nicht in die Selbstisolation f{\"u}hren, sondern der Erz{\"a}hlzusammenhang verdeutlicht, dass es eine M{\"o}glichkeit der R{\"u}ckkehr zur Gruppe und Vergebung f{\"u}r einen einsichtigen S{\"u}nder gibt.}, language = {de} } @misc{Bauer2019, author = {Bauer, Matthias}, title = {Sozialer und semiotischer Raum}, issn = {2364-9224}, doi = {10.15475/skms.2018.2.5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-7833}, pages = {143 -- 168}, year = {2019}, abstract = {In den Gesellschafts- wie in den Kulturwissenschaften hat der Begriff des ‚Raums' in den letzten Jahren sehr viel Aufmerksamkeit erfahren. Zahlreiche Einzelstudien, Sammelb{\"a}nde und Handb{\"u}cher loten den Bedeutungsumfang dieses Begriffs, aber auch die Schwierigkeiten aus, die sich einerseits aus der Vielfalt vorhandener Raumkonzepte und andererseits aus der F{\"u}lle ihrer keineswegs deckungsgleichen Anwendungsm{\"o}glichkeiten ergeben. Hinzu kommt die Schwierigkeit, den Begriff des Raums von verwandten Ausdr{\"u}cken wie Platz und Ort, Umgebung und Territorium oder gar Welt abzugrenzen - ganz zu schweigen von den Verschiebungen, die zwischen verschiedenen Sprachen hinsichtlich der Auffassung von ‚Raum', ‚espace', ‚space' usw. bestehen. Vor diesem Hintergrund erscheint es nicht nur zweckm{\"a}ßig, sondern notwendig, im Rahmen einer transversalen Betrachtung nach strukturellen {\"A}hnlichkeiten zwischen den Raumkonzepten unterschiedlicher Disziplinen Ausschau zu halten. Einen Versuch in dieser Richtung stellen die folgenden {\"U}berlegungen zu Querbez{\"u}gen und {\"U}berg{\"a}ngen zwischen Raumsoziologie und Raumsemiotik dar.}, language = {de} } @phdthesis{Bauer2016, author = {Bauer, Matthias}, title = {Containerbr{\"u}ckeneinsatzplanung in Seehafencontainerterminals - Entwurf und experimentelle Analyse von L{\"o}sungsverfahren f{\"u}r das Container Sequencing Problem}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-4218}, school = {Universit{\"a}t Passau}, year = {2016}, abstract = {Durch den Einsatz immer gr{\"o}ßerer Containerschiffe zum Transport containerisierter G{\"u}ter {\"u}ber den Seeweg gewinnt die Produktivit{\"a}t der zur Be- und Entladung der Containerschiffe eingesetzten Containerbr{\"u}cken in Seehafencontainerterminals immer mehr an Bedeutung. Einen erheblichen Einfluss auf die Produktivit{\"a}t der Containerbr{\"u}cken hat die Containerbr{\"u}ckeneinsatzplanung. Gegenstand dieser Arbeit ist das im Rahmen der Containerbr{\"u}ckeneinsatzplanung auftretende Container Sequencing Problem, welches hier erstmals unter Ber{\"u}cksichtigung von Ladelukendeckeln und Rehandlecontainern verschiedener Containerkategorien untersucht wird. Die Problemstellung wird als ganzzahliges lineares Optimierungsmodell formuliert. Zur L{\"o}sung des Problems werden verschiedene heuristische Verfahren vorgeschlagen. Deren Leistungsf{\"a}higkeit wird anhand numerischer Experimente analysiert.}, subject = {Containerterminal}, language = {de} } @misc{Bauer2016, author = {Bauer, Matthias}, title = {Szenopragmatik}, doi = {10.15475/skms.2016.1.1}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-4079}, pages = {7-38}, year = {2016}, abstract = {Wie h{\"a}ngen Zeichen, Szenen und Medien in der Lebenswelt des Menschen zusammen? Eine Antwort auf diese Frage erfordert konzeptionelle {\"U}berlegungen, die sich synoptisch zu einer Reihe relevanter Theorien verhalten m{\"u}ssen. Wie die einschl{\"a}gigen Begriffe, aufeinander bezogen werden k{\"o}nnten, soll hier - eher vorl{\"a}ufig als abschließend - erkundet werden.}, language = {de} } @misc{BauerBruemmerNiesetal.2016, author = {Bauer, Matthias and Br{\"u}mmer, Tanja and Nies, Martin and Stolz, Christian}, title = {Projektvorstellung: Katastrophen-Diegese und Katastrophen-Exegese (KDE)}, doi = {10.15475/skms.2016.1.5}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-4122}, pages = {107-118}, year = {2016}, abstract = {Projekt des Virtuellen Zentrums f{\"u}r kultursemiotische Forschung zum Verh{\"a}ltnis von Erkl{\"a}rung und Erz{\"a}hlung sowie von natur- und kulturwissenschaftlicher Erkenntnis.}, language = {de} } @misc{BauerRoesslerKasperetal.2025, author = {Bauer, Matthias and R{\"o}ssler, Reto and Kasper, Nils and Ernst, Christoph}, title = {Diagrammatische Praktiken}, volume = {2025}, number = {14}, editor = {Bauer, Matthias and R{\"o}ssler, Reto and Nies, Martin}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-20417}, pages = {134}, year = {2025}, abstract = {Indem die Aufs{\"a}tze von Nils Kasper, Christoph Ernst, Reto R{\"o}ssler und Matthias Bauer sowohl wissens- und kulturgeschichtliche als auch medien- und verfahrenstechnische Fragestellungen behandeln, zeigen sie in ihrer Komplementarit{\"a}t das Spektrum an Denk- und Handlungsm{\"o}glichkeiten auf, das Diagramme bzw. diagrammatische Praktiken er{\"o}ffnen.}, language = {de} } @article{BaumannPfretzschnerRutter2024, author = {Baumann, Jakob and Pfretzschner, Matthias and Rutter, Ignaz}, title = {Parameterized complexity of vertex splitting to pathwidth at most 1}, series = {Theoretical Computer Science}, volume = {2024}, journal = {Theoretical Computer Science}, number = {1021}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1879-2294}, doi = {10.1016/j.tcs.2024.114928}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-19195}, pages = {15 Seiten}, year = {2024}, abstract = {Motivated by the planarization of 2-layered straight-line drawings, we consider the problem of modifying a graph such that the resulting graph has pathwidth at most 1. The problem Pathwidth-One Vertex Explosion (POVE) asks whether such a graph can be obtained using at most 𝑘 vertex explosions, where a vertex explosion replaces a vertex 𝑣 by deg(𝑣) degree-1 vertices, each incident to exactly one edge that was originally incident to 𝑣. For POVE, we give an FPT algorithm with running time 𝑂(4𝑘 ⋅ 𝑚) and an 𝑂(𝑘2) kernel, thereby improving over the 𝑂(𝑘6) kernel by Ahmed et al. [2] in a more general setting. Similarly, a vertex split replaces a vertex 𝑣 by two distinct vertices 𝑣1 and 𝑣2 and distributes the edges originally incident to 𝑣 arbitrarily to 𝑣1 and 𝑣2. Analogously to POVE, we define the problem variant Pathwidth-One Vertex Splitting (POVS) that uses the split operation instead of vertex explosions. Here we obtain a linear kernel and an algorithm with running time 𝑂((6𝑘 + 12)𝑘 ⋅ 𝑚). This answers an open question by Ahmed et al. [2]. Finally, we consider the problem Π-VertexSplitting (Π-VS), which generalizes the problem POVS and asks whether a given graph can be turned into a graph of a specific graph class Π using at most 𝑘 vertex splits. For graph classes Π that can be dfined in monadic second-order graph logic (MSO2), we show that the problem Π-VS can be expressed as an MSO2 formula, resulting in an FPT algorithm for Π-VS parameterized by 𝑘 if Π additionally has bounded treewidth. We obtain the same result for the problem variant using vertex explosions. [2] R. Ahmed, S.G. Kobourov, M. Kryven, An FPT algorithm for bipartite vertex splitting, in: P. Angelini, R. von Hanxleden (Eds.), Graph Drawing and Network Visualization -30th International Symposium, GD 2022, in: Lecture Notes in Computer Science, vol.13764, Springer, 2022, pp.261--268.}, language = {en} } @phdthesis{Baumgartner2023, author = {Baumgartner, Isolde}, title = {Der Einfluss von Aufgabenmerkmalen auf situationales Interesse im Fach Geschichte}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-12785}, school = {Universit{\"a}t Passau}, pages = {316 Seiten}, year = {2023}, abstract = {Welche Typen von Lernaufgaben werden von Jugendlichen als interessant und bedeutsam wahrgenommen? Lassen sich positive Zusammenh{\"a}nge zwischen Aufgabenmerkmalen und aufgabenbezogenem situationalem Interesse von Sch{\"u}lerinnen und Sch{\"u}lern herstellen? Diese Arbeit untersucht auf der Basis von Interessentheorien die Wirkung von Aufgabenmerkmalen auf situationales Interesse im Fach Geschichte. Aufgrund haupts{\"a}chlich normativ gesetzter geschichtsdidaktischer Vorschl{\"a}ge zur Lernaufgabengestaltung fehlt bislang ein empirisch {\"u}berpr{\"u}ftes Klassifikationsschema zur Beschreibung von unterschiedlichen Aufgabenmerkmalen. Die vorliegende Studie stellt die Entwicklung eines Aufgabenkategoriensystems vor und untersucht den Zusammenhang zwischen Aufgabenmerkmalen und aufgabenspezifischem situationalem Interesse [Aufgabeninteressantheit (AI) und subjektive Bedeutsamkeit (SB)] von Lernenden. Als Aufgabenmerkmale ließen sich ‚Aufgabenschwierigkeit', ‚Offenheit der Aufgabenstellung' (Aufgabenstruktur), ‚Kognitive Anforderungen', ‚Lebensweltbezug', ‚Oberfl{\"a}chenmerkmale' (grafische Elemente) und ‚Aufgabenumfang' (Leseaufwand und Schreibaufwand) feststellen und wurden hinsichtlich AI und SB n{\"a}her untersucht. Es wurden insgesamt 801 bayerische Realsch{\"u}lerinnen und Realsch{\"u}ler (30 Klassen) der 9. Jahrgangsstufe dreimal innerhalb eines Zeitraums von zwei bis drei Wochen im Rahmen eines lernaufgabengesteuerten Unterrichts befragt. Nach {\"U}berpr{\"u}fung des Klassifikationsschemas zeigten multiple Regressionsanalysen, dass in den Einzelanalysen (Betrachtung der einzelnen Aufgabenmerkmale) AI vorwiegend durch schwierige Aufgaben, wenig strukturierte Aufgaben, Aufgaben mit hohen kognitiven Anforderungen sowie Aufgaben mit reiner Textdarstellung und hohem Lese- und Schreibaufwand vorhergesagt wurde, w{\"a}hrend SB nur durch Aufgaben mit Lebensweltbezug und Aufgaben mit hohem Leseaufwand pr{\"a}diziert wurde. Betrachtet man die Gesamtmodelle (Aufnahme aller Aufgabenmerkmale ins Modell) unter Ber{\"u}cksichtigung von Multikollinearit{\"a}t, zeigten sich positive Effekte auf SB bei Aufgaben mit dem Erfordernis eines historischen Werturteils, das ein In-Beziehung-Setzen des historischen Geschehens mit der eigenen Gegenwart impliziert. Hinsichtlich AI und SB zeigten sich positive Effekte bei Aufgaben mit hohem Leseaufwand. Negative Effekte auf AI ließen sich bei schwierigen Aufgaben und Aufgaben mit hohem Schreibaufwand feststellen. Hinsichtlich AI und SB zeigten sich negative Effekte bei Aufgaben mit reiner Textdarstellung. Der signifikant positive Einfluss von Aufgaben mit hohem Leseaufwand auf AI und SB deutet auf einen Pr{\"a}diktor hin, der Ans{\"a}tze f{\"u}r Nachfolgestudien im Fach Geschichte bietet. Da besonders die Lesekompetenz eine Voraussetzung und Teil historischer Kompetenz darstellt, sollte z. B. auf die Textschwierigkeit mehr Aufmerksamkeit gerichtet werden. Auch die Ergebnisse zum Schreibaufwand weisen auf Untersuchungsans{\"a}tze hin, welche Aufgabenkonstruktionen mit dem Erfordernis historischer Werturteile betreffen.}, subject = {Lernaufgabenforschung}, language = {de} } @misc{Baumgartner2014, author = {Baumgartner, Isolde}, title = {Einfluss von Fachinteresse auf situationales Interesse bei der Bearbeitung von Aufgaben im Fach Geschichte. Eine Treatment-Studie mit Variation der Aufgabeninteressantheit am Beispiel „Deutscher Widerstand im Nationalsozialismus"}, doi = {10.15475/paradigma.2014.1.9}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus-27588}, pages = {12}, year = {2014}, abstract = {Die Studie geht der Frage nach, welchen Einfluss individuelles Fachinteresse auf das aufgabenbezogene situationale Interesse im Unterrichtsfach Geschichte hat. Dabei wurde zwischen zwei Klassen unterschieden. W{\"a}hrend die eine Klasse mit {\"a}sthetisch manipuliertem Aufgabenmaterial arbeitete, bekam die andere Aufgaben ohne {\"a}sthetische Aufwertung. Die Aufgabenstellung war in beiden Klassen dieselbe. An der Studie nahmen 55 bayerische Realsch{\"u}ler/ innen der 10. Jahrgangsstufe teil. Der Vergleich der Mittelwerte des aufgabenbezogenen situationalen Interesses erbringt jedoch nur bei hoch an Geschichte interessierten Sch{\"u}ler/inne/n Unterschiede; bei ihnen f{\"o}rdert eine {\"a}sthetische Aufwertung des Arbeitsmaterials das situationale Interesse. Signifikant positive Korrelationen zwischen Fachinteresse und situationalem Interesse lassen sich sowohl auf Gesamtebene als auch auf Aufgabenebene feststellen.}, subject = {Lernaufgabe}, language = {de} } @article{BecherGerl2022, author = {Becher, Stefan and Gerl, Armin}, title = {ConTra Preference Language: Privacy Preference Unification via Privacy Interfaces}, series = {Sensors}, volume = {22}, journal = {Sensors}, number = {14}, editor = {Sarne, Giuseppe Maria Luigi and Ma, Jianhua and Rosaci, Domenico and Srivastava, Gautam}, publisher = {MDPI}, address = {Basel, Switzerland}, issn = {1424-8220}, doi = {10.3390/s22145428}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-11218}, pages = {18 Seiten}, year = {2022}, abstract = {After the enactment of the GDPR in 2018, many companies were forced to rethink their privacy management in order to comply with the new legal framework. These changes mostly affect the Controller to achieve GDPR-compliant privacy policies and management.However, measures to give users a better understanding of privacy, which is essential to generate legitimate interest in the Controller, are often skipped. We recommend addressing this issue by the usage of privacy preference languages, whereas users define rules regarding their preferences for privacy handling. In the literature, preference languages only work with their corresponding privacy language, which limits their applicability. In this paper, we propose the ConTra preference language, which we envision to support users during privacy policy negotiation while meeting current technical and legal requirements. Therefore, ConTra preferences are defined showing its expressiveness, extensibility, and applicability in resource-limited IoT scenarios. In addition, we introduce a generic approach which provides privacy language compatibility for unified preference matching.}, language = {en} } @phdthesis{Beck2003, author = {Beck, Alexandra}, title = {Die Einkaufsst{\"a}ttenwahl von Konsumenten unter transaktionskostentheoretischen Gesichtspunkten. Theoretische Grundlegung und empirische {\"U}berpr{\"u}fung mittels der Adaptiven Conjoint-Analyse}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus-318}, school = {Universit{\"a}t Passau}, year = {2003}, abstract = {Ziel der Arbeit war die Entwicklung eines theoretischen Bezugsrahmens auf Basis der Transaktionskostentheorie, um die Einkaufsst{\"a}ttenwahl von Konsumenten unter transaktionskostentheoretischen Gesichtspunkten analysieren zu k{\"o}nnen und die anschließende empirische {\"U}berpr{\"u}fung der theoretischen Erkenntnisse. Nach der Darstellung bisheriger Ans{\"a}tze zur Erkl{\"a}rung der Einkaufsst{\"a}ttenwahl von Konsumenten wurde der Transaktionskostenansatz ausf{\"u}hrlich beschrieben und gepr{\"u}ft, ob die Transaktionskostentheorie auf die Einkaufsst{\"a}ttenwahl anwendbar ist. Nachdem die grundlegende Frage des Einsatzes der Transaktionskostentheorie gekl{\"a}rt war, wurden die einzelnen Arten an Transaktionskosten, die bei der Einkaufsst{\"a}ttenwahl anfallen k{\"o}nnen, herausgearbeitet. Ein Konsument sucht die Einkaufsst{\"a}tte auf und kauft dort seine Ware, wo seine subjektiven Gesamtkosten, die sich aus dem Preis sowie Transaktionskosten und -nutzen zusammensetzen, am geringsten sind. Ausgehend von den theoretischen Erkenntnissen erfolgte eine ausf{\"u}hrliche Analyse der Betriebstypenevolution unter transaktionskostentheoretischen Gesichtspunkten. Anschließend wurden Untersuchungshypothesen aufgestellt, um die unter transaktionskostentheoretischen Gesichtspunkten f{\"u}r die einzelnen Betriebstypen entscheidungsrelevanten Kriterien herauszufiltern und m{\"o}gliche Einflussfaktoren festzustellen. Nach Auswahl des Untersuchungsobjektes, Operationalisierung der Modellvariablen und der Messmodelle sowie Bestimmung des Erhebungsdesign wurden die Hypothesen in einer empirischen Untersuchung getestet. Ein Teil der Befragung erfolgte dabei computergest{\"u}tzt mittels der Adaptiven Conjoint-Analyse. Als Ergebnis l{\"a}sst sich festhalten, dass die Einkaufsst{\"a}ttenwahl von Konsumenten neben dem Preis von Transaktionskosten und Transaktionsnutzen abh{\"a}ngig ist. Die Transaktionskostentheorie liefert einen leistungsf{\"a}higen Bezugsrahmen, um die oft schwer nachzuvollziehende Einkaufsst{\"a}ttenwahl von Konsumenten wissenschaftlich zu erhellen.}, subject = {Kaufverhalten}, language = {de} } @phdthesis{Beck2012, author = {Beck, Lotte}, title = {Anticorruption in Public Procurement - A Qualitative Research Design}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus-26801}, school = {Universit{\"a}t Passau}, year = {2012}, abstract = {This qualitative approach to research develops a case oriented design in order to examine risks of corruption in public procurement. The method involves expert interviews as the most important data collection tool and explains how to examine the information by means of a qualitative content analyze. In order to develop rigor results, the concepts of external validity, construct validity, internal validity and reliability are applied. The research design was adopted in two field investigations: A first project focuses on the challenges and chances for anticorruption when awarding contracts in a competitive dialogue. For this purpose, data was collected in an investigation of the German construction market. The results are presented in form of 16 propositions, also including policy recommendations and approaches for reform. In the framework of a further case based research project, the paper analyzes the organizational structure and working process of "China's Tangible Construction Market" (TCM). The TCM is an administrative institution where a bid inviter can register in order to announce a public need and conduct a procurement procedure at a fixed location. The analysis of expert interviews conducted during an investigation of the Chinese construction market shows that the TCM offers strong institutional support that can be helpful to curb corruption in public procurement}, subject = {{\"O}ffentliche Ausschreibung}, language = {en} } @phdthesis{Behm2022, author = {Behm, Svenia}, title = {Four essays on statistical modelling of environmental data}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-10539}, school = {Universit{\"a}t Passau}, pages = {XIII, 137 Seiten}, year = {2022}, abstract = {This dissertation deals with geostatistical, time series, and regression analytical approaches for modelling spatio-temporal processes, using air quality data in the applications. The work is structured into four essays the abstracts of which are given in the following. The first essay is titled 'Spatial detrending revisited: Modelling local trend patterns in NO2-concentration in Belgium and Germany'. It is written in co-authorship by Prof. Dr. Harry Haupt and Dr. Angelika Schmid and published in 2018 in Spatial Statistics 28, pp. 331-351 (https://doi.org/10.1016/j.spasta.2018.04.004). Abstract Short-term predictions of air pollution require spatial modelling of trends, heterogeneities, and dependencies. Two-step methods allow real-time computations by separating spatial detrending and spatial extrapolation into two steps. Existing methods discuss trend models for specific environments and require specification search. Given more complex environments, specification search gets complicated by potential nonlinearities and heterogeneities. This research embeds a nonparametric trend modelling approach in real-time two-step methods. Form and complexity of trends are allowed to vary across heterogeneous environments. The proposed method avoids ad hoc specifications and potential generated predictor problems in previous contributions. Examining Belgian and German air quality and land use data, local trend patterns are investigated in a data driven way and are compared to results computed with existing methods and variations thereof. An important aspect of our empirical illustration is the heterogeneity and superior performance of local trend patterns for both research regions. The findings suggest that a nonparametric spatial trend modelling approach is a valuable tool for real-time predictions of pollution variables: it avoids specification search, provides useful exploratory insights and reduces computational costs. The second essay is titled 'Predictability of hourly nitrogen dioxide concentration'. It is written in co-authorship with Prof. Dr. Harry Haupt and published in 2020 in Ecological Modelling 428, 109076 (https://doi.org/10.1016/j.ecolmodel.2020.109076). Abstract Temporal aggregation of air quality time series is typically used to investigate stylized facts of the underlying series such as multiple seasonal cycles. While aggregation reduces complexity, commonly used aggregates can suffer from non-representativeness or non-robustness. For example, definitions of specific events such as extremes are subjective and may be prone to data contaminations. The aim of this paper is to assess the predictability of hourly nitrogen dioxide concentrations and to explore how predictability depends on (i) level of temporal aggregation, (ii) hour of day, and (iii) concentration level. Exploratory tools are applied to identify structural patterns, problems related to commonly used aggregate statistics and suitable statistical modeling philosophies, capable of handling multiple seasonalities and non-stationarities. Hourly times series and subseries of daily measurements for each hour of day are used to investigate the predictability of pollutant levels for each hour of day, with prediction horizons ranging from one hour to one week ahead. Predictability is assessed by time series cross validation of a loss function based on out-of-sample prediction errors. Empirical evidence on hourly nitrogen dioxide measurements suggests that predictability strongly depends on conditions (i)-(iii) for all statistical models: for specific hours of day, models based on daily series outperform models based on hourly series, while in general predictability deteriorates with exposure level. The third essay is titled 'Agglomeration and infrastructure effects in land use regression models for air pollution - Specification, estimation, and interpretations'. It is written in co-authorship with Dr. Markus Fritsch and published in 2021 in Atmospheric Environment 253, 118337 (https://doi.org/10.1016/j.atmosenv.2021.118337). Abstract Established land use regression (LUR) techniques such as linear regression utilize extensive selection of predictors and functional form to fit a model for every data set on a given pollutant. In this paper, an alternative to established LUR modeling is employed, which uses additive regression smoothers. Predictors and functional form are selected in a data-driven way and ambiguities resulting from specification search are mitigated. The approach is illustrated with nitrogen dioxide (NO2) data from German monitoring sites using the spatial predictors longitude, latitude, altitude and structural predictors; the latter include population density, land use classes, and road traffic intensity measures. The statistical performance of LUR modeling via additive regression smoothers is contrasted with LUR modeling based on parametric polynomials. Model evaluation is based on goodness of fit, predictive performance, and a diagnostic test for remaining spatial autocorrelation in the error terms. Additionally, interpretation and counterfactual analysis for LUR modeling based on additive regression smoothers are discussed. Our results have three main implications for modeling air pollutant concentration levels: First, modeling via additive regression smoothers is supported by a specification test and exhibits superior in- and out-of-sample performance compared to modeling based on parametric polynomials. Second, different levels of prediction errors indicate that NO2 concentration levels observed at background and traffic/industrial monitoring sites stem from different processes. Third, accounting for agglomeration and infrastructure effects is important: NO2 concentration levels tend to increase around major cities, surrounding agglomeration areas, and their connecting road traffic network. The fourth essay is titled 'Outlier detection and visualisation in multi-seasonal time series and its application to hourly nitrogen dioxide concentration'. It is written in single authorship and has not been published yet. Abstract Outlier detection in data on air pollutant recordings is conducted to uncover data points that refer to either invalid measurements or valid but unusually high concentration levels. As air pollutant data is typically characterised by multiple seasonalities, the task of outlier detection is associated with the question of how to deal with such non-stationarities. The present work proposes a method that combines time series segmentation, seasonal adjustment, and standardisation of random variables. While the former two are employed to obtain subseries of homoskedastic data, the latter ensures comparability across the subseries. Further, the standardised version of the seasonally adjusted subseries represents a scaled measure for the outlyingness of each data point in the original time series from its mean and therefore forms a suitable basis for outlier detection. In an empirical application to data on hourly NO2 concentration levels recorded at a traffic monitoring site in Cologne, Germany, over the years 2016 to 2019, the common boxplot criterion is used to examine each standardised seasonally adjusted subseries for positive outliers. The results of the analyses are put into their natural temporal order and displayed in a heatmap layout that provides information on when single and sequential outliers occur.}, subject = {Statistik}, language = {en} } @phdthesis{Beierl2021, author = {Beierl, Stefan}, title = {Public Works Programmes: Review of their effectiveness and empirical essays on their contribution to climate resilience and social cohesion}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:739-opus4-10491}, school = {Universit{\"a}t Passau}, pages = {vii, 154 Seiten}, year = {2021}, abstract = {Poverty, underemployment, lack of infrastructure, low agricultural productivity, degradation of natural resources, climate change, and eroding social cohesion are among the biggest challenges that many low and lower-middle income countries are facing. Objectives linked to addressing these pressing challenges have been ascribed to public works programmes (PWPs). These are social protection instruments which offer remuneration (in cash or kind) for vulnerable people in exchange for temporary work on labour-intensive low-skill activities with social benefits. PWPs are being implemented in around two out of three developing countries. Given the substantial amounts spent on PWPs, it is critical to know to what extent the expectations towards them are backed by evidence. This dissertation sheds light on this overarching question with three self-contained essays. The first essay synthesises the evidence from PWPs in Sub-Saharan Africa, guided by three questions: First, what can we infer from the available impact evaluations regarding the effectiveness of PWPs as a social protection instrument? Second, what do we know about the role of the wage vector, asset vector, and skills vector in this respect? Third, what can we infer about the role of design features in explaining differences in outcomes? The other two essays use empirical evidence from Malawi to address more specific questions regarding the potential of PWPs to strengthen climate resilience and the relationship between PWPs and social cohesion. What sets the evidence synthesis in my first essay apart from existing reviews of PWPs is that it accounts for their heterogeneity by systematically differentiating results by PWP type and outcome area (income, consumption and expenditures, labour supply, food security, nutrition, asset holdings, agricultural production and techniques, and education). Programmes that offer short-term ad-hoc employment (Type 1) are distinguished from programmes that offer more predictable employment over longer periods (Type 2). For the review of impacts, this paper relies solely on (quasi-)experimental studies, but for the analysis of the role of design factors also on other literature. In line with existing reviews, my results suggest that Type 1 programmes can effectively enable consumption smoothing in the wake of acute crises, whereas in contexts of chronic poverty, Type 2 programmes perform, on balance, better. Offering complementary access to extension services in Type 2 programmes can boost impacts further. However, in all cases, evidence is too scant and mixed to safely conclude whether the higher benefits of costlier PWP types justify the cost premium. The second essay investigates the potential of PWPs to strengthen climate resilience. Among the main social protection instruments, the biggest potential to strengthen climate resilience is often ascribed to PWPs if they create climate-smart community assets and transfer knowledge of climate-smart practices. Yet, there is a lack of evidence whether design changes to this end can indeed enhance the contribution of an existing PWP to climate resilience. I use a difference-in-differences approach based on two-period panel data to analyse how a modified PWP model performs compared to the standard model of Malawi's largest PWP after 24 months. The key modification is to embed public works in a communal watershed management plan with a strong emphasis on collective action and capacity building. I find that the modified approach considerably increased communal watershed management activities through voluntary labour contributions on top of the paid public works labour. While this increase was mainly driven by PWP participants, non-participants also made substantial contributions. I also find a small increase in the adoption of soil and water conservation practices on respondents' private land, especially by non-PWP participants. These findings imply that such modest changes can make PWPs climate-smarter. In particular, they can broaden the engagement in and adoption of climate-smart activities beyond the group of PWP participants. The co-authored third essay investigates the relationship between Malawi's MASAF PWP and social cohesion, specifically within-community cooperation for the common good. Like the existing studies, we face the challenge that neither the assignment of the programme to communities nor the selection of individual participants is randomised. We try to mitigate the endogeneity concerns by triangulating fixed effects panel analyses for a set of outcomes and sectors using two datasets with different units of analysis (households and communities). We find that public works are positively associated with coordination activities and voluntary (unpaid) contributions to public goods, along both vertical ties (between community members and local leaders) and horizontal ties (among community members). Especially for school-building activities, voluntary inputs in the form of labour and other in-kind contributions are higher in the presence of the public works programme. Our results contribute to a better understanding of the link between social protection programmes with community-driven features and social cohesion. Overall, the findings of the three essays in this dissertation contribute to the knowledge base regarding effectiveness and potential of PWPs across a broad range of outcome areas. Specifically, they offer new insights how to harness the potential of PWP to strengthen climate resilience and into the seemingly positive relationship between PWPs and social cohesion. The findings can help researchers and policy makers who are interested specifically in PWPs or in any of the many objectives that can be pursued through PWPs.}, language = {en} }