@article{LazaridesGniewosz2024, author = {Lazarides, Rebecca and Gniewosz, Burkhard}, title = {Modelling develpoment and change of motivational beliefs}, series = {Motivation and emotion in learning and teaching across educational contexts : theoretical and methodological perspectives and empirical insights}, journal = {Motivation and emotion in learning and teaching across educational contexts : theoretical and methodological perspectives and empirical insights}, publisher = {Routledge}, address = {New York}, isbn = {978-1-032-30109-9}, doi = {10.4324/9781003303473-15}, pages = {197 -- 212}, year = {2024}, abstract = {This chapter provides an overview of methods to capture developments and changes in motivational beliefs. Motivational research has recently begun to venture beyond just examining average developmental trends in motivational variables by starting to investigate how developmental changes in motivational variables differ between and within individuals in different learning situations and across contexts. Although studies have started to uncover differences in motivational changes, a systematic overview of suitable methods for capturing motivational differences in developmental processes is still missing. In this chapter, we review key methods of change modelling, bringing together variable-centred approaches, such as growth modelling and true intraindividual change (TIC) models, and person-centred approaches, such as latent transition and growth mixture models. We illustrate the value of the reviewed statistical methods for the analysis of context-specific motivational changes by reviewing recent empirical studies that identify different patterns and trajectories of such motivational beliefs across time. Our focus is thereby on research grounded in situated expectancy-value theory as a core theory in motivational research.}, language = {en} } @book{OPUS4-62873, title = {Motivation and emotion in learning and teaching across educational contexts}, editor = {Hagenauer, Gerda and Lazarides, Rebecca and J{\"a}rvenoja, Hanna}, publisher = {Routledge}, address = {London}, isbn = {978-1-032-30109-9}, doi = {10.4324/9781003303473}, pages = {292}, year = {2024}, abstract = {Motivation and Emotion in Learning and Teaching across Educational Contexts brings together current theoretical and methodological perspectives as well as examples of empirical implementations from leading international researchers focusing on the context specificity and situatedness of their core theories in motivation and emotion. The book is compiled of two main sections. Section I covers theoretical reflections and perspectives on the main theories on emotion and motivation in learning and teaching and their transferability across different educational contexts illustrated with empirical examples. Section II addresses the methodological reflections and perspectives on the methodology that is needed to address the complexity and context specificity of motivation and emotion. In addition to general reflections and perspectives regarding methodology, concrete empirical examples are provided. All cutting-edge chapters include current empirical studies on emotions and motivation in learning and teaching across different contexts (age groups, domains, countries, etc.) making them applicable and relevant to a wide range of contexts and settings. This high-quality volume with contributions from leading international experts will be an essential resource for researchers, students and teacher trainers interested in the vital role that motivation and emotions can play in education.}, language = {en} } @phdthesis{Behrmann2024, author = {Behrmann, Helga}, title = {Digital Fashion}, doi = {10.25932/publishup-62026}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-620269}, school = {Universit{\"a}t Potsdam}, pages = {309}, year = {2024}, abstract = {Das virtuelle Kleid als mediale und soziokulturelle Alltagserscheinung der Gegenwart bildet den Gegenstand der vorliegenden interdisziplin{\"a}ren Unter-suchung. An der Schnittstelle zwischen Menschen, Medien und Mode ist das virtuelle Kleid an unrealen Orten und in synthetischen Situationen ausschließlich auf einem Screen erfahrbar. In diesem Dispositiv lassen sich K{\"o}rperkonzepte, Darstellungskonventionen, soziale Handlungsmuster und Kommunikations-strategien ausmachen, die zwar auf einer radikalen Abl{\"o}sung vom textilen Material beruhen, aber dennoch nicht ohne sehr konkrete Verweise auf das textile Material auskommen. Dies f{\"u}hrt zu neuen Ans{\"a}tzen der Auseinandersetzung mit Kleidern, die nun als Visualisierung geb{\"u}ndelter Datenpakete zu betrachten sind. Die dynamische Entwicklung neuer Erscheinungsformen und deren nahtlose Einbindung in traditionelle Gesch{\"a}ftsmodelle und bestehende Modekonzepte macht eine Positionsbestimmung notwendig, insbesondere im Hinblick auf gegenw{\"a}rtige Nachhaltigkeitsdiskurse um immaterielle Produkte. F{\"u}r diese Studie liefern die hinter den Bildern liegenden Prozesse der {\"o}konomischen Ausrichtung, der Herstellung, der Verwendung und der Rezeption den methodologischen Zugang f{\"u}r die Analyse. Mithilfe eines typologisierenden Instrumentariums wird aus der Vielzahl und Vielfalt der Darstellungen ein Set an forschungsleitenden Beispielen zusammengestellt, welche dann in einer mehrstufigen Kontextanalyse zu einer begrifflichen Fassung des virtuellen Kleides sowie zu f{\"u}nf Kontexteinheiten f{\"u}hren. Am Beispiel des virtuellen Kleides zeichnet diese Untersuchung den technischen, gesellschaftlichen und sozialen Wandel nach und arbeitet seine Bedeutung f{\"u}r zuk{\"u}nftige Modeentwicklungen heraus. Damit leistet die Untersuchung einen Beitrag zur medien- und sozialwissenschaftlichen Modeforschung der Gegenwart.}, language = {de} } @phdthesis{Koehler2024, author = {K{\"o}hler, Wolfgang}, title = {Challenges of efficient and compliant data processing}, doi = {10.25932/publishup-62784}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-627843}, school = {Universit{\"a}t Potsdam}, pages = {195}, year = {2024}, abstract = {Die fortschreitende Digitalisierung ver{\"a}ndert die Gesellschaft und hat weitreichende Auswirkungen auf Menschen und Unternehmen. Grundlegend f{\"u}r diese Ver{\"a}nderungen sind die neuen technologischen M{\"o}glichkeiten, Daten in immer gr{\"o}ßerem Umfang und f{\"u}r vielf{\"a}ltige neue Zwecke zu verarbeiten. Von besonderer Bedeutung ist dabei die Verf{\"u}gbarkeit großer und qualitativ hochwertiger Datens{\"a}tze, insbesondere auf Basis personenbezogener Daten. Sie werden entweder zur Verbesserung der Produktivit{\"a}t, Qualit{\"a}t und Individualit{\"a}t von Produkten und Dienstleistungen oder gar zur Entwicklung neuartiger Dienstleistungen verwendet. Heute wird das Nutzerverhalten, trotz weltweit steigender gesetzlicher Anforderungen an den Schutz personenbezogener Daten, aktiver und umfassender verfolgt als je zuvor. Dies wirft vermehrt ethische, moralische und gesellschaftliche Fragen auf, die nicht zuletzt durch popul{\"a}re F{\"a}lle des Datenmissbrauchs in den Vordergrund der politischen Debatte ger{\"u}ckt sind. Angesichts dieses Diskurses und der gesetzlichen Anforderungen muss heutiges Datenmanagement drei Bedingungen erf{\"u}llen: Erstens die Legalit{\"a}t bzw. Gesetzeskonformit{\"a}t der Nutzung, zweitens die ethische Legitimit{\"a}t. Drittens sollte die Datennutzung aus betriebswirtschaftlicher Sicht wertsch{\"o}pfend sein. Im Rahmen dieser Bedingungen verfolgt die vorliegende kumulative Dissertation vier Forschungsziele mit dem Fokus, ein besseres Verst{\"a}ndnis (1) der Herausforderungen bei der Umsetzung von Gesetzen zum Schutz von Privatsph{\"a}re, (2) der Faktoren, die die Bereitschaft der Kunden zur Weitergabe pers{\"o}nlicher Daten beeinflussen, (3) der Rolle des Datenschutzes f{\"u}r das digitale Unternehmertum und (4) der interdisziplin{\"a}ren wissenschaftlichen Bedeutung, deren Entwicklung und Zusammenh{\"a}nge zu erlangen.}, language = {en} } @phdthesis{Shipova2024, author = {Shipova, Evgeniya}, title = {Formal analysis of {\`e}to-clefts in Russian: syntax and semantics}, doi = {10.25932/publishup-63014}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-630149}, school = {Universit{\"a}t Potsdam}, pages = {219}, year = {2024}, abstract = {{\`E}to-clefts are Russian focus constructions with the demonstrative pronoun {\`e}to 'this' at the beginning: "{\`E}to Mark vyigral gonku" ("It was Mark who won the race"). They are often being compared with English it-clefts, German es-clefts, as well as the corresponding focus-background structures in other languages. In terms of semantics, {\`e}to-clefts have two important properties which are cross-linguistically typical for clefts: existence presupposition ("Someone won the race") and exhaustivity ("Nobody except Mark won the race"). However, the exhaustivity effects are not as strong as exhaustivity effects in structures with the exclusive only and require more research. At the same time, the question if the syntactic structure of {\`e}to-clefts matches the biclausal structure of English and German clefts, remains open. There are arguments in favor of biclausality, as well as monoclausality. Besides, there is no consistency regarding the status of {\`e}to itself. Finally, the information structure of {\`e}to-clefts has remained underexplored in the existing literature. This research investigates the information-structural, syntactic, and semantic properties of Russian clefts, both theoretically (supported by examples from Russian text corpora and judgments from native speakers) and experimentally. It is determined which desired changes in the information structure motivate native speakers to choose an {\`e}to-cleft and not the canonical structure or other focus realization tools. Novel syntactic tests are conducted to find evidence for bi-/monoclausality of {\`e}to-clefts, as well as for base-generation or movement of the cleft pivot. It is hypothesized that {\`e}to has a certain important function in clefts, and its status is investigated. Finally, new experiments on the nature of exhaustivity in {\`e}to-clefts are conducted. They allow for direct cross-linguistic comparison, using an incremental-information paradigm with truth-value judgments. In terms of information structure, this research makes a new proposal that presents {\`e}to-clefts as structures with an inherent focus-background bipartitioning. Even though {\`e}to-clefts are used in typical focus contexts, evidence was found that {\`e}to-clefts (as well as Russian thetic clefts) allow for both new information focus and contrastive focus. {\`E}to-clefts are pragmatically acceptable when a singleton answer to the implied question is expected (e.g. "It was Mark who won the race" but not "It was Mark who came to the party"). Importantly, {\`e}to in Russian clefts is neither dummy, nor redundant, but is a topic expression; conveys familiarity which triggers existence presupposition; refers to an instantiated event, or a known/perceivable situation; finally, {\`e}to plays an important role in the spoken language as a tool for speech coherency and a focus marker. In terms of syntax, this research makes a new monoclausal proposal and shows evidence that the cleft pivot undergoes movement to the left peripheral position. {\`E}to is proposed to be TopP. Finally, in terms of semantics, a novel cross-linguistic evaluation of Russian clefts is made. Experiments show that the exhaustivity inference in {\`e}to-clefts is not robust. Participants used different strategies in resolving exhaustivity, falling into 2 groups: one group considered {\`e}to-clefts exhaustive, while another group considered them non-exhaustive. Hence, there is evidence for the pragmatic nature of exhaustivity in {\`e}to-clefts. The experimental results for {\`e}to-clefts are similar to the experimental results for clefts in German, French and Akan. It is concluded that speakers use different tools available in their languages to produce structures with similar interpretive properties.}, language = {en} } @phdthesis{Rubertus2024, author = {Rubertus, Elina}, title = {Coarticulatory changes across childhood}, doi = {10.25932/publishup-63012}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-630123}, school = {Universit{\"a}t Potsdam}, pages = {X, 131}, year = {2024}, abstract = {The present dissertation investigates changes in lingual coarticulation across childhood in German-speaking children from three to nine years of age and adults. Coarticulation refers to the mismatch between the abstract phonological units and their seemingly commingled realization in continuous speech. Being a process at the intersection of phonology and phonetics, addressing its changes across childhood allows for insights in speech motor as well as phonological developments. Because specific predictions for changes in coarticulation across childhood can be derived from existing speech production models, investigating children's coarticulatory patterns can help us model human speech production. While coarticulatory changes may shed light on some of the central questions of speech production development, previous studies on the topic were sparse and presented a puzzling picture of conflicting findings. One of the reasons for this lack is the difficulty in articulatory data acquisition in a young population. Within the research program this dissertation is embedded in, we accepted this challenge and successfully set up the hitherto largest corpus of articulatory data from children using ultrasound tongue imaging. In contrast to earlier studies, a high number of participants in tight age cohorts across a wide age range and a thoroughly controlled set of pseudowords allowed for statistically powerful investigations of a process known as variable and complicated to track. The specific focus of my studies is on lingual vocalic coarticulation as measured in the horizontal position of the highest point of the tongue dorsum. Based on three studies on a) anticipatory coarticulation towards the left, b) carryover coarticulation towards the right side of the utterance, and c) anticipatory coarticulatory extent in repeated versus read aloud speech, I deduct the following main theses: 1. Maturing speech motor control is responsible for some developmental changes in coarticulation. 2. Coarticulation can be modeled as the coproduction of articulatory gestures. 3. The developmental change in coarticulation results from a decrease of vocalic activation width.}, language = {en} } @phdthesis{Martin2024, author = {Martin, Katja}, title = {Beerdigen oder verbrennen?}, publisher = {arijeh-verlag}, address = {Potsdam}, isbn = {978-3-944693-04-0}, school = {Universit{\"a}t Potsdam}, pages = {398}, year = {2024}, language = {de} } @article{GohlSchrauth2024, author = {Gohl, Niklas and Schrauth, Philipp}, title = {JUE insight : ticket to paradise?}, series = {Journal of urban economics}, journal = {Journal of urban economics}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0094-1190}, doi = {10.1016/j.jue.2024.103643}, year = {2024}, abstract = {This paper provides novel evidence on the impact of public transport subsidies on air pollution. We obtain causal estimates by leveraging a unique policy intervention in Germany that temporarily reduced nationwide prices for regional public transport to a monthly flat rate price of 9 Euros. Using DiD estimation strategies on air pollutant data, we show that this intervention causally reduced a benchmark air pollution index by more than eight percent and, after its termination, increased again. Our results illustrate that public transport subsidies - especially in the context of spatially constrained cities - offer a viable alternative for policymakers and city planers to improve air quality, which has been shown to crucially affect health outcomes.}, language = {en} } @phdthesis{Fitzner2024, author = {Fitzner, Maria}, title = {Cultivation of selected halophytes in saline indoor farming and modulation of cultivation conditions to optimize metabolite profiles for human nutrition}, doi = {10.25932/publishup-62697}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-626974}, school = {Universit{\"a}t Potsdam}, pages = {178}, year = {2024}, abstract = {With the many challenges facing the agricultural system, such as water scarcity, loss of arable land due to climate change, population growth, urbanization or trade disruptions, new agri-food systems are needed to ensure food security in the future. In addition, healthy diets are needed to combat non-communicable diseases. Therefore, plant-based diets rich in health-promoting plant secondary metabolites are desirable. A saline indoor farming system is representing a sustainable and resilient new agrifood system and can preserve valuable fresh water. Since indoor farming relies on artificial lighting, assessment of lighting conditions is essential. In this thesis, the cultivation of halophytes in a saline indoor farming system was evaluated and the influence of cultivation conditions were assessed in favor of improving the nutritional quality of halophytes for human consumption. Therefore, five selected edible halophyte species (Brassica oleracea var. palmifolia, Cochlearia officinalis, Atriplex hortensis, Chenopodium quinoa, and Salicornia europaea) were cultivated in saline indoor farming. The halophyte species were selected for to their salt tolerance levels and mechanisms. First, the suitability of halophytes for saline indoor farming and the influence of salinity on their nutritional properties, e.g. plant secondary metabolites and minerals, were investigated. Changes in plant performance and nutritional properties were observed as a function of salinity. The response to salinity was found to be species-specific and related to the salt tolerance mechanism of the halophytes. At their optimal salinity levels, the halophytes showed improved carotenoid content. In addition, a negative correlation was found between the nitrate and chloride content of halophytes as a function of salinity. Since chloride and nitrate can be antinutrient compounds, depending on their content, monitoring is essential, especially in halophytes. Second, regional brine water was introduced as an alternative saline water resource in the saline indoor farming system. Brine water was shown to be feasible for saline indoor farming of halophytes, as there was no adverse effect on growth or nutritional properties, e.g. carotenoids. Carotenoids were shown to be less affected by salt composition than by salt concentration. In addition, the interaction between the salinity and the light regime in indoor farming and greenhouse cultivation has been studied. There it was shown that interacting light regime and salinity alters the content of carotenoids and chlorophylls. Further, glucosinolate and nitrate content were also shown to be influenced by light regime. Finally, the influence of UVB light on halophytes was investigated using supplemental narrow-band UVB LEDs. It was shown that UVB light affects the growth, phenotype and metabolite profile of halophytes and that the UVB response is species specific. Furthermore, a modulation of carotenoid content in S. europaea could be achieved to enhance health-promoting properties and thus improve nutritional quality. This was shown to be dose-dependent and the underlying mechanisms of carotenoid accumulation were also investigated. Here it was revealed that carotenoid accumulation is related to oxidative stress. In conclusion, this work demonstrated the potential of halophytes as alternative vegetables produced in a saline indoor farming system for future diets that could contribute to ensuring food security in the future. To improve the sustainability of the saline indoor farming system, LED lamps and regional brine water could be integrated into the system. Since the nutritional properties have been shown to be influenced by salt, light regime and UVB light, these abiotic stressors must be taken into account when considering halophytes as alternative vegetables for human nutrition.}, language = {en} } @phdthesis{Li2024, author = {Li, Yunfei}, title = {On the influence of density and morphology on the Urban Heat Island intensity}, doi = {10.25932/publishup-62150}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-621504}, school = {Universit{\"a}t Potsdam}, pages = {xviii, 119}, year = {2024}, abstract = {The urban heat island (UHI) effect, describing an elevated temperature of urban areas compared with their natural surroundings, can expose urban dwellers to additional heat stress, especially during hot summer days. A comprehensive understanding of the UHI dynamics along with urbanization is of great importance to efficient heat stress mitigation strategies towards sustainable urban development. This is, however, still challenging due to the difficulties of isolating the influences of various contributing factors that interact with each other. In this work, I present a systematical and quantitative analysis of how urban intrinsic properties (e.g., urban size, density, and morphology) influence UHI intensity. To this end, we innovatively combine urban growth modelling and urban climate simulation to separate the influence of urban intrinsic factors from that of background climate, so as to focus on the impact of urbanization on the UHI effect. The urban climate model can create a laboratory environment which makes it possible to conduct controlled experiments to separate the influences from different driving factors, while the urban growth model provides detailed 3D structures that can be then parameterized into different urban development scenarios tailored for these experiments. The novelty in the methodology and experiment design leads to the following achievements of our work. First, we develop a stochastic gravitational urban growth model that can generate 3D structures varying in size, morphology, compactness, and density gradient. We compare various characteristics, like fractal dimensions (box-counting, area-perimeter scaling, area-population scaling, etc.), and radial gradient profiles of land use share and population density, against those of real-world cities from empirical studies. The model shows the capability of creating 3D structures resembling real-world cities. This model can generate 3D structure samples for controlled experiments to assess the influence of some urban intrinsic properties in question. [Chapter 2] With the generated 3D structures, we run several series of simulations with urban structures varying in properties like size, density and morphology, under the same weather conditions. Analyzing how the 2m air temperature based canopy layer urban heat island (CUHI) intensity varies in response to the changes of the considered urban factors, we find the CUHI intensity of a city is directly related to the built-up density and an amplifying effect that urban sites have on each other. We propose a Gravitational Urban Morphology (GUM) indicator to capture the neighbourhood warming effect. We build a regression model to estimate the CUHI intensity based on urban size, urban gross building volume, and the GUM indicator. Taking the Berlin area as an example, we show the regression model capable of predicting the CUHI intensity under various urban development scenarios. [Chapter 3] Based on the multi-annual average summer surface urban heat island (SUHI) intensity derived from Land surface temperature, we further study how urban intrinsic factors influence the SUHI effect of the 5,000 largest urban clusters in Europe. We find a similar 3D GUM indicator to be an effective predictor of the SUHI intensity of these European cities. Together with other urban factors (vegetation condition, elevation, water coverage), we build different multivariate linear regression models and a climate space based Geographically Weighted Regression (GWR) model that can better predict SUHI intensity. By investigating the roles background climate factors play in modulating the coefficients of the GWR model, we extend the multivariate linear model to a nonlinear one by integrating some climate parameters, such as the average of daily maximal temperature and latitude. This makes it applicable across a range of background climates. The nonlinear model outperforms linear models in SUHI assessment as it captures the interaction of urban factors and the background climate. [Chapter 4] Our work reiterates the essential roles of urban density and morphology in shaping the urban thermal environment. In contrast to many previous studies that link bigger cities with higher UHI intensity, we show that cities larger in the area do not necessarily experience a stronger UHI effect. In addition, the results extend our knowledge by demonstrating the influence of urban 3D morphology on the UHI effect. This underlines the importance of inspecting cities as a whole from the 3D perspective. While urban 3D morphology is an aggregated feature of small-scale urban elements, the influence it has on the city-scale UHI intensity cannot simply be scaled up from that of its neighbourhood-scale components. The spatial composition and configuration of urban elements both need to be captured when quantifying urban 3D morphology as nearby neighbourhoods also cast influences on each other. Our model serves as a useful UHI assessment tool for the quantitative comparison of urban intervention/development scenarios. It can support harnessing the capacity of UHI mitigation through optimizing urban morphology, with the potential of integrating climate change into heat mitigation strategies.}, language = {en} } @techreport{BruttelEisenkopfNithammer2024, type = {Working Paper}, author = {Bruttel, Lisa Verena and Eisenkopf, Gerald and Nithammer, Juri}, title = {Pre-election communication in public good games with endogenous leaders}, series = {CEPA Discussion Papers}, journal = {CEPA Discussion Papers}, number = {73}, issn = {2628-653X}, doi = {10.25932/publishup-62395}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-623952}, pages = {28}, year = {2024}, abstract = {Leadership plays an important role for the efficient and fair solution of social dilemmas but the effectiveness of a leader can vary substantially. Two main factors of leadership impact are the ability to induce high contributions by all group members and the (expected) fair use of power. Participants in our experiment decide about contributions to a public good. After all contributions are made, the leader can choose how much of the joint earnings to assign to herself; the remainder is distributed equally among the followers. Using machine learning techniques, we study whether the content of initial open statements by the group members predicts their behavior as a leader and whether groups are able to identify such clues and endogenously appoint a "good" leader to solve the dilemma. We find that leaders who promise fairness are more likely to behave fairly, and that followers appoint as leaders those who write more explicitly about fairness and efficiency. However, in their contribution decision, followers focus on the leader's first-move contribution and place less importance on the content of the leader's statements.}, language = {en} } @techreport{EstrinKhavulKritikosetal.2024, type = {Working Paper}, author = {Estrin, Saul and Khavul, Susanna and Kritikos, Alexander and L{\"o}her, Jonas}, title = {Access to digital finance}, series = {CEPA Discussion Papers}, journal = {CEPA Discussion Papers}, number = {72}, issn = {2628-653X}, doi = {10.25932/publishup-62326}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-623261}, pages = {27}, year = {2024}, abstract = {Financing entrepreneurship spurs innovation and economic growth. Digital financial platforms that crowdfund equity for entrepreneurs have emerged globally, yet they remain poorly understood. We model equity crowdfunding in terms of the relationship between the number of investors and the amount of money raised per pitch. We examine heterogeneity in the average amount raised per pitch that is associated with differences across three countries and seven platforms. Using a novel dataset of successful fundraising on the most prominent platforms in the UK, Germany, and the USA, we find the underlying relationship between the number of investors and the amount of money raised for entrepreneurs is loglinear, with a coefficient less than one and concave to the origin. We identify significant variation in the average amount invested in each pitch across countries and platforms. Our findings have implications for market actors as well as regulators who set competitive frameworks.}, language = {en} } @phdthesis{Baumgart2024, author = {Baumgart, Lene}, title = {Die Ambivalenz der Digitalisierung}, doi = {10.25932/publishup-63040}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-630401}, school = {Universit{\"a}t Potsdam}, pages = {137}, year = {2024}, abstract = {Ausgehend von der Beobachtung, dass die aktuelle Digitalisierungsforschung die Ambivalenz der Digitalisierung zwar erkennt, aber nicht zum Gegenstand ihrer Analysen macht, fokussiert die vorliegende kumulative Dissertation auf die ambivalente Dichotomie aus Potenzialen und Problemen, die mit digitalen Transformationen von Organisationen einhergeht. Entlang von sechs Publikationen wird mit einem systemtheoretischen Blick auf Organisationen die spannungsvolle Dichotomie hinsichtlich dreier ambivalenter Verh{\"a}ltnisse aufgezeigt: Erstens wird in Bezug auf das Verh{\"a}ltnis von Digitalisierung und Postb{\"u}rokratie deutlich, dass digitale Transformationen das Potenzial aufweisen, postb{\"u}rokratische Arbeitsweisen zu erleichtern. Parallel ergibt sich das Problem, dass auf Konsens basierende postb{\"u}rokratische Strukturen Digitalisierungsinitiativen erschweren, da diese auf eine Vielzahl von Entscheidungen angewiesen sind. Zweitens zeigt sich mit Blick auf das ambivalente Verh{\"a}ltnis von Digitalisierung und Vernetzung, dass einerseits organisationsweite Kooperation erm{\"o}glicht wird, w{\"a}hrend sich andererseits die Gefahr digitaler Widerspruchskommunikation auftut. Beim dritten Verh{\"a}ltnis zwischen Digitalisierung und Gender deutet sich das mit neuen digitalen Technologien einhergehende Potenzial f{\"u}r Gender Inklusion an, w{\"a}hrend zugleich das Problem einprogrammierter Gender Biases auftritt, die Diskriminierungen oftmals versch{\"a}rfen. Durch die Gegen{\"u}berstellung der Potenziale und Probleme wird nicht nur die Ambivalenz organisationaler Digitalisierung analysierbar und verst{\"a}ndlich, es stellt sich auch heraus, dass mit digitalen Transformationen einen doppelte Formalisierung einhergeht: Organisationen werden nicht nur mit den f{\"u}r Reformen {\"u}blichen Anpassungen der formalen Strukturen konfrontiert, sondern m{\"u}ssen zus{\"a}tzlich formale Entscheidungen zu Technikeinf{\"u}hrung und -beibehaltung treffen sowie formale L{\"o}sungen etablieren, um auf unvorhergesehene Potenziale und Probleme reagieren. Das Ziel der Dissertation ist es, eine analytisch generalisierte Heuristik an die Hand zu geben, mit deren Hilfe die Errungenschaften und Chancen digitaler Transformationen identifiziert werden k{\"o}nnen, w{\"a}hrend sich parallel ihr Verh{\"a}ltnis zu den gleichzeitig entstehenden Herausforderungen und Folgeproblemen erkl{\"a}ren l{\"a}sst.}, language = {de} } @book{BrosiusGersdorfGersdorf2024, author = {Brosius-Gersdorf, Frauke and Gersdorf, Hubertus}, title = {Das neue System der Beschaffung von Leistungen zur medizinischen Rehabilitation durch die Rentenversicherung}, publisher = {Duncker \& Humblot}, address = {Berlin}, isbn = {978-3-428-19066-9}, doi = {10.3790/978-3-428-59066-7}, pages = {168}, year = {2024}, abstract = {Die Beschaffung von Leistungen zur medizinischen Rehabilitation wurde durch den neuen \S 15 SGB VI zum 1. Juli 2023 grundlegend reformiert. Seither gilt ein mehrstufiges System aus Zulassung der Rehabilitationskliniken, Belegungsvertrag, Belegungsentscheidung und Verg{\"u}tung. S{\"a}mtliche Beschaffungsstufen werden von der DRV Bund durch verbindliche Entscheidungen gesteuert. Dieses neue Beschaffungssystem verst{\"o}ßt gegen das Wettbewerbsrecht der Europ{\"a}ischen Union und ist deshalb unwirksam. Das Unionsrecht (Art. 106 Abs. 1 AEUV), aber auch das nationale Kartellrecht (\S 19 Abs. 2 Nr. 1 GWB) und das Verfassungsrecht (Art. 12 Abs. 1 GG) verlangen eine Trennung von hoheitlichen Befugnissen und unternehmerischen Funktionen der Rentenversicherungstr{\"a}ger. Anderenfalls ist die gebotene Gleichbehandlung (Nichtdiskriminierung) der Rehabilitationskliniken freigemeinn{\"u}tziger und privater Tr{\"a}ger mit den Rehabilitationskliniken der Rentenversicherungstr{\"a}ger bei der Erbringung von Leistungen zur medizinischen Rehabilitation nicht gew{\"a}hrleistet. Dieses Trennungsprinzip ist verletzt. Denn die Rentenversicherungstr{\"a}ger nehmen hoheitliche Zulassungs-, Belegungs- und Verg{\"u}tungsaufgaben wahr und sind gleichzeitig unternehmerisch mit eigenen Rehabilitationseinrichtungen auf dem Markt der Erbringung von Leistungen zur medizinischen Rehabilitation t{\"a}tig. Freigemeinn{\"u}tzige und private Rehabilitationskliniken werden auf allen Stufen der Beschaffung gegen{\"u}ber den Kliniken der Rentenversicherungstr{\"a}ger diskriminiert. Das gilt insbesondere f{\"u}r die Belegungsentscheidungen der Rentenversicherungstr{\"a}ger, weil hierdurch systematisch eigene Kliniken gegen{\"u}ber freigemeinn{\"u}tzigen und privaten Kliniken beg{\"u}nstigt werden.}, language = {de} } @phdthesis{Grohmann2024, author = {Grohmann, Nils-Hendrik}, title = {Strengthening the UN Human Rights Treaty Bodies}, series = {Jus Internationale et Europaeum}, journal = {Jus Internationale et Europaeum}, number = {202}, publisher = {Mohr Siebeck}, address = {T{\"u}bingen}, isbn = {978-3-16-162825-2}, issn = {1861-1893}, doi = {10.1628/978-3-16-162826-9}, pages = {XV, 315}, year = {2024}, abstract = {Nils-Hendrik Grohmann besch{\"a}ftigt sich mit dem noch andauernden St{\"a}rkungsprozess der UN-Menschenrechtsvertragsorgane. Er analysiert, welche rechtlichen Befugnisse die Aussch{\"u}sse haben, ob sie von sich aus Vorschl{\"a}ge einbringen k{\"o}nnen und inwieweit sie ihre Verfahrensweisen bisher aufeinander abgestimmt haben. Ein weiterer Schwerpunkt liegt auf der Zusammenarbeit zwischen den verschiedenen Aussch{\"u}ssen und der Frage, welche Rolle das Treffen der Vorsitzenden bei der St{\"a}rkung spielen kann.}, language = {en} } @phdthesis{AlhosseiniAlmodarresiYasin2024, author = {Alhosseini Almodarresi Yasin, Seyed Ali}, title = {Classification, prediction and evaluation of graph neural networks on online social media platforms}, doi = {10.25932/publishup-62642}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-626421}, school = {Universit{\"a}t Potsdam}, pages = {xviii, 78}, year = {2024}, abstract = {The vast amount of data generated on social media platforms have made them a valuable source of information for businesses, governments and researchers. Social media data can provide insights into user behavior, preferences, and opinions. In this work, we address two important challenges in social media analytics. Predicting user engagement with online content has become a critical task for content creators to increase user engagement and reach larger audiences. Traditional user engagement prediction approaches rely solely on features derived from the user and content. However, a new class of deep learning methods based on graphs captures not only the content features but also the graph structure of social media networks. This thesis proposes a novel Graph Neural Network (GNN) approach to predict user interaction with tweets. The proposed approach combines the features of users, tweets and their engagement graphs. The tweet text features are extracted using pre-trained embeddings from language models, and a GNN layer is used to embed the user in a vector space. The GNN model then combines the features and graph structure to predict user engagement. The proposed approach achieves an accuracy value of 94.22\% in classifying user interactions, including likes, retweets, replies, and quotes. Another major challenge in social media analysis is detecting and classifying social bot accounts. Social bots are automated accounts used to manipulate public opinion by spreading misinformation or generating fake interactions. Detecting social bots is critical to prevent their negative impact on public opinion and trust in social media. In this thesis, we classify social bots on Twitter by applying Graph Neural Networks. The proposed approach uses a combination of both the features of a node and an aggregation of the features of a node's neighborhood to classify social bot accounts. Our final results indicate a 6\% improvement in the area under the curve score in the final predictions through the utilization of GNN. Overall, our work highlights the importance of social media data and the potential of new methods such as GNNs to predict user engagement and detect social bots. These methods have important implications for improving the quality and reliability of information on social media platforms and mitigating the negative impact of social bots on public opinion and discourse.}, language = {en} } @phdthesis{Antonoglou2024, author = {Antonoglou, Nikolaos}, title = {GNSS-based remote sensing: Innovative observation of key hydrological parameters in the Central Andes}, doi = {10.25932/publishup-62825}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-628256}, school = {Universit{\"a}t Potsdam}, pages = {xxii, 116}, year = {2024}, abstract = {The Central Andean region is characterized by diverse climate zones with sharp transitions between them. In this work, the area of interest is the South-Central Andes in northwestern Argentina that borders with Bolivia and Chile. The focus is the observation of soil moisture and water vapour with Global Navigation Satellite System (GNSS) remote-sensing methodologies. Because of the rapid temporal and spatial variations of water vapour and moisture circulations, monitoring this part of the hydrological cycle is crucial for understanding the mechanisms that control the local climate. Moreover, GNSS-based techniques have previously shown high potential and are appropriate for further investigation. This study includes both logistic-organization effort and data analysis. As for the prior, three GNSS ground stations were installed in remote locations in northwestern Argentina to acquire observations, where there was no availability of third-party data. The methodological development for the observation of the climate variables of soil moisture and water vapour is independent and relies on different approaches. The soil-moisture estimation with GNSS reflectometry is an approximation that has demonstrated promising results, but it has yet to be operationally employed. Thus, a more advanced algorithm that exploits more observations from multiple satellite constellations was developed using data from two pilot stations in Germany. Additionally, this algorithm was slightly modified and used in a sea-level measurement campaign. Although the objective of this application is not related to monitoring hydrological parameters, its methodology is based on the same principles and helps to evaluate the core algorithm. On the other hand, water-vapour monitoring with GNSS observations is a well-established technique that is utilized operationally. Hence, the scope of this study is conducting a meteorological analysis by examining the along-the-zenith air-moisture levels and introducing indices related to the azimuthal gradient. The results of the experiments indicate higher-quality soil moisture observations with the new algorithm. Furthermore, the analysis using the stations in northwestern Argentina illustrates the limits of this technology because of varying soil conditions and shows future research directions. The water-vapour analysis points out the strong influence of the topography on atmospheric moisture circulation and rainfall generation. Moreover, the GNSS time series allows for the identification of seasonal signatures, and the azimuthal-gradient indices permit the detection of main circulation pathways.}, language = {en} } @phdthesis{MartinezGuajardo2024, author = {Mart{\´i}nez Guajardo, Alejandro}, title = {New zwitterionic polymers for antifouling applications}, doi = {10.25932/publishup-62682}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-626820}, school = {Universit{\"a}t Potsdam}, pages = {XIX, 145}, year = {2024}, abstract = {The remarkable antifouling properties of zwitterionic polymers in controlled environments are often counteracted by their delicate mechanical stability. In order to improve the mechanical stabilities of zwitterionic hydrogels, the effect of increased crosslinker densities was thus explored. In a first approach, terpolymers of zwitterionic monomer 3-[N -2(methacryloyloxy)ethyl-N,N-dimethyl]ammonio propane-1-sulfonate (SPE), hydrophobic monomer butyl methacrylate (BMA), and photo-crosslinker 2-(4-benzoylphenoxy)ethyl methacrylate (BPEMA) were synthesized. Thin hydrogel coatings of the copolymers were then produced and photo-crosslinked. Studies of the swollen hydrogel films showed that not only the mechanical stability but also, unexpectedly, the antifouling properties were improved by the presence of hydrophobic BMA units in the terpolymers. Based on the positive results shown by the amphiphilic terpolymers and in order to further test the impact that hydrophobicity has on both the antifouling properties of zwitterionic hydrogels and on their mechanical stability, a new amphiphilic zwitterionic methacrylic monomer, 3-((2-(methacryloyloxy)hexyl)dimethylammonio)propane-1-sulfonate (M1), was synthesized in good yields in a multistep synthesis. Homopolymers of M1 were obtained by free-radical polymerization. Similarly, terpolymers of M1, zwitterionic monomer SPE, and photo-crosslinker BPEMA were synthesized by free-radical copolymerization and thoroughly characterized, including its solubilities in selected solvents. Also, a new family of vinyl amide zwitterionic monomomers, namely 3-(dimethyl(2-(N -vinylacetamido)ethyl)ammonio)propane-1-sulfonate (M2), 4-(dimethyl(2-(N-vinylacetamido)ethyl)ammonio)butane-1-sulfonate (M3), and 3-(dimethyl(2-(N-vinylacetamido)ethyl)ammonio)propyl sulfate (M4), together with the new photo-crosslinker 4-benzoyl-N-vinylbenzamide (M5) that is well-suited for copolymerization with vinylamides, are introduced within the scope of the present work. The monomers are synthesized with good yields developing a multistep synthesis. Homopolymers of the new vinyl amide zwitterionic monomers are obtained by free-radical polymerization and thoroughly characterized. From the solubility tests, it is remarkable that the homopolymers produced are fully soluble in water, evidence of their high hydrophilicity. Copolymerization of the vinyl amide zwitterionic monomers, M2, M3, and M4 with the vinyl amide photo-crosslinker M5 proved to require very specific polymerization conditions. Nevertheless, copolymers were successfully obtained by free-radical copolymerization under appropriate conditions. Moreover, in an attempt to mitigate the intrinsic hydrophobicity introduced in the copolymers by the photo-crosslinkers, and based on the proven affinity of quaternized diallylamines to copolymerize with vinyl amides, a new quaternized diallylamine sulfobetaine photo-crosslinker 3-(diallyl(2-(4-benzoylphenoxy)ethyl)ammonio)propane-1-sulfonate (M6) is synthesized. However, despite a priori promising copolymerization suitability, copolymerization with the vinyl amide zwitterionic monomers could not be achieved.}, language = {en} } @phdthesis{Benson2024, author = {Benson, Lawrence}, title = {Efficient state management with persistent memory}, doi = {10.25932/publishup-62563}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:517-opus4-625637}, school = {Universit{\"a}t Potsdam}, pages = {xiii, 124}, year = {2024}, abstract = {Efficiently managing large state is a key challenge for data management systems. Traditionally, state is split into fast but volatile state in memory for processing and persistent but slow state on secondary storage for durability. Persistent memory (PMem), as a new technology in the storage hierarchy, blurs the lines between these states by offering both byte-addressability and low latency like DRAM as well persistence like secondary storage. These characteristics have the potential to cause a major performance shift in database systems. Driven by the potential impact that PMem has on data management systems, in this thesis we explore their use of PMem. We first evaluate the performance of real PMem hardware in the form of Intel Optane in a wide range of setups. To this end, we propose PerMA-Bench, a configurable benchmark framework that allows users to evaluate the performance of customizable database-related PMem access. Based on experimental results obtained with PerMA-Bench, we discuss findings and identify general and implementation-specific aspects that influence PMem performance and should be considered in future work to improve PMem-aware designs. We then propose Viper, a hybrid PMem-DRAM key-value store. Based on PMem-aware access patterns, we show how to leverage PMem and DRAM efficiently to design a key database component. Our evaluation shows that Viper outperforms existing key-value stores by 4-18x for inserts while offering full data persistence and achieving similar or better lookup performance. Next, we show which changes must be made to integrate PMem components into larger systems. By the example of stream processing engines, we highlight limitations of current designs and propose a prototype engine that overcomes these limitations. This allows our prototype to fully leverage PMem's performance for its internal state management. Finally, in light of Optane's discontinuation, we discuss how insights from PMem research can be transferred to future multi-tier memory setups by the example of Compute Express Link (CXL). Overall, we show that PMem offers high performance for state management, bridging the gap between fast but volatile DRAM and persistent but slow secondary storage. Although Optane was discontinued, new memory technologies are continuously emerging in various forms and we outline how novel designs for them can build on insights from existing PMem research.}, language = {en} } @phdthesis{Woebbeking2024, author = {W{\"o}bbeking, Cordula}, title = {K{\"o}rper - Karte - Text}, series = {Sanssouci - Forschungen zur Romanistik}, volume = {22}, journal = {Sanssouci - Forschungen zur Romanistik}, publisher = {Frank \& Timme}, address = {Berlin}, isbn = {978-3-7329-1016-8}, issn = {2193-9985}, school = {Universit{\"a}t Potsdam}, pages = {280}, year = {2024}, abstract = {Rabelais' Pentalogie um die Riesen Gargantua und Pantagruel spiegelt Aspekte des sich ver{\"a}ndernden Weltbildes ihrer Entstehungszeit. Diese Studie untersucht auf der Folie der Theorie des Simulakrum Schrift, wie K{\"o}rpermodellierungen und kartographisches imaginaire durch den Autor als Strategien der Verh{\"u}llung verborgener Botschaften eingesetzt werden. Sie zeigt an ausgew{\"a}hlten Beispielen des Quart Livre die Aufweichung der Grenzen von K{\"o}rper, Karte und Text und deren Durchdringung. Die Metaphorizit{\"a}t des Textes gibt Aufschluss {\"u}ber seine Autoreflexivit{\"a}t und bewirkt eine gleichsam ganzheitliche Lekt{\"u}reerfahrung. Schließlich avanciert die Fiktion in ihrer Trugbildhaftigkeit als grotesk-sinnlicher K{\"o}rper und polysemantische Karte zum Welterkl{\"a}rungsmodell, das jedoch erst dechiffriert werden muss.}, language = {de} }