Over the past decade, accelerating digital innovation has transformed how firms, consumers, and individuals interact. Digital transformation is a broad socioeconomic shift driven by the adoption of digital technologies, such as cloud computing, big data, artificial intelligence, and the Internet of Things. It has opened new avenues for value creation and shifted interactions from human-centered to technology-mediated. As digital transformation influences ecosystems rather than just individual organizations, I adopt a multi-level perspective to understand its impact on interrelated actors and systems. This dissertation examines how digital transformation shapes technology-mediated interactions at three levels: inter- and intra-firm relationships (macro level), consumer-firm touchpoints (meso level), and individual consumer identity (micro level). Despite a growing focus on digital technologies in marketing research, a comprehensive, multi-level understanding of how digital transformation influences technology-mediated interactions remains limited. This dissertation addresses this gap by answering the overarching research question: How do digital transformations shape technology-mediated interactions at the macro, meso, and micro levels? This question will be addressed across three independent essays. Essay 1 focuses on the macro level, examining how digital transformation affects technology-mediated intra- and inter-firm relationships between customer and provider firms. Essay 2 examines the meso level and explores how emerging technologies, such as AI-enabled agents, influence consumer perceptions and reactions. Essay 3 covers the micro level, exploring how digital transformation, particularly the use of avatars as consumer embodiments in technology-mediated spaces, affects consumers' individual identities. Together, these essays offer new theoretical and practical insights into the evolving nature of technology-mediated interactions, while highlighting the transformative role of digital innovation across organizational, relational, and individual contexts.

With rapid advances in digitization, many critical processes in transportation, industries, and our daily life rely on sensor measurements. With time, however, the measurements may get gradually biased and their precision deteriorates, leading to an enhanced risk of major disruptions caused by false sensor measurements. All single sensor measurements are uncertain and deviate from the true value. To detect malfunctioning sensors early on, a set of recent measurements of each sensor has to be constantly cross-checked against the measurements of a given number of other sensors, i.e., sensors should form a diagnosable network. In this article, we examine the intelligent positioning of safety-relevant sensors at railways such that the installed sensors can constantly cross-check each other and the number of the required sensors is minimized. The arising sensor positioning problem (SPP) belongs to the family of the coordinated set covering problems with two binary matrices: the choice of columns in one matrix implies the selection of specific columns and rows in the other matrix. We formulate an integer program, provide some formal analysis of the SPP and design a customized large neighborhood search metaheuristic RuM, which finds close-to-optimality solutions fast. In our computational experiments, we show that if we ignore the diagnosability requirement, the installed sensors cannot sufficiently cross-check each other in most cases. However, it costs only a few (or even no) additional sensors to ensure the diagnosability of the sensor network.

This report presents the results of the project “Migration and Translocality in West Africa (MiTra|WA)” with reference to translocal practices in Burkina Faso. Funded by the German Federal Ministry of Education and Research, the study ran from 2022 to 2024. The general objective of the project is to analyse the multiple links between the rural areas of departure and urban reception of migrants as well as the impacts on the development of these localities. The study employs a mixed-methods approach, combining quantitative and qualitative research methods. The quantitative component consisted of two types of surveys. First, a household survey in the migrants' area of origin (AoO) to identify the migrants’ belonging to these households. In the second phase, a telephone survey was conducted among migrants in the destination areas (AoD). Then, the focus was on socio-economic data as well as translocal interactions and network relationships. The qualitative component consisted of in-depth interviews with key actors in the different areas of departure and destination of migrants. These include migrants, local administrative officials, leaders of NGOs, associations, community and religious leaders. The results show that migration is a phenomenon experienced by many households in rural areas. There are as many internal migrants as there are international migrants. Of the 537 households surveyed, 405 (75.4%) have at least one migrant. The age structure of migrants shows a predominantly young structure of migrants (82% who are under 40 years old). According to gender, migration is strongly male-dominated (82%). Men are more inclined to international migration (56%). Female migration is precocious. A large proportion of migrants (41%) have no level of education and are mostly single (50%). Translocality, conceptualized in this study as the multifaceted links between the places of departure, transit and residence of migrants, is apprehended through telephone contacts between migrants and their place of origin, in addition to the different forms of mobility: mobility of people, financial resources (remittances), material resources (transfers in kind), intangible resources (ideas, practices, etc.). Exchanges are often bidirectional. Telephone contacts represent 86% of migrants. Migrants visit the household in the area of origin more frequently (41.8%) than they receive household members at their destination (33.9%). More than 66.6% of migrants transfer remittances to their households in rural areas. With regard to the 4-level translocality intensity indicator (Wehner 2022), it can be concluded that over 50% of migrants are located at the two highest levels. Hence, translocality is an important feature of rural-urban migration in Burkina Faso.

Die ansteigende Relevanz umweltfreundlicher Mobilität und die gesteigerte Förderung des Fahrradfahrens in städtischen Gebieten spiegeln den verstärkten Fokus auf nachhaltige Verkehrsmittel wider. Städte müssen auf die zunehmenden Verkehrsbelastungen und Umweltprobleme reagieren, wobei der Fahrradverkehr als eine umweltfreundliche Alternative eine wichtige Rolle einnimmt. In diesem Kontext richtet sich die Aufmerksamkeit dieser Arbeit auf Gunzenhausen, eine Stadt im Fränkischen Seenland, die sich bereits seit Jahren aktiv darum bemüht, ihre Fahrradfreundlichkeit zu verbessern. Die im Rahmen dieser Untersuchung durch geführten Umfrage konzentriert sich auf die unterschiedliche Wahrnehmung der Fahrradfreundlichkeit zwischen Einheimischen und Touristen. Dabei ist von Interesse, ob und in welchem Ausmaß diese beiden Gruppen Unterschiede in ihrer Wahrnehmung der Fahrradfreundlichkeit in Gunzenhausen aufweisen. Die Analyse der Ergebnisse macht differierende Ansichten zwischen Einheimischen und Touristen hinsichtlich der Fahrradfreundlichkeit sichtbar. Diese Unterschiede reflektieren individuelle Perspektiven und Erfahrungen, die relevante Konsequenzen für zukünftige Stadtentwicklung darstellen können. Trotz eher geringer Unterschiede ist es wichtig, diese verschiedenen Sichtweisen zu berücksichtigen, um eine weitere Auseinanderentwicklung zu vermeiden. Die gewonnenen Erkenntnisse betonen die Notwendigkeit, ebendiese Unterschiede genauer zu erforschen, um die Fahrradfreundlichkeit in Gunzenhausen zu verbessern und die Ansichten von Einheimischen und Touristen sogar angleichen zu können. Im Kontext der globalen Entwicklung hin zu nachhaltigen Verkehrsmitteln und umweltfreundlichen Mobilitätslösungen gewinnt die Analyse der Fahrradfreundlichkeit in Städten wie Gunzenhausen immer mehr an Relevanz. Die Ergebnisse und die daraus folgenden Erkenntnisse dieser Untersuchung können als Grundlage für eine an den Bedürfnissen verschiedener Bevölkerungsgruppen ausgerichtete Stadtentwicklung dienen. Sowohl die Zukunft des Radfahrens als Verkehrsmittel als auch die Erhaltung und Erweiterung seiner Attraktivität bleiben in Bezug auf die Anpassung städtischer Infrastrukturen weiterhin von Interesse. Die Berücksichtigung unterschiedlicher Perspektiven, wie die für diese Arbeit ausgewählten, kann dabei helfen, eine umfassendere Mobilitätsstrategie zu entwickeln, die die Stadt Gunzenhausen und ähnliche Gebiete umweltfreundlicher und auch lebenswerter gestaltet.