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Global Facility Location Decision making: an in-depth investigation into multilevel information alignment- relationships, structuring and boundaries
No full textGlobal facility location decisions (GFLDs) are essential for organizational strategy, involving the decision to set up manufacturing facilities, warehouses, and distribution centers. This study explores GFLDs, focusing on aligning micro-level attributes (firm priorities, strategies) with macro-level factors (labor, logistics, government incentives, transportation infrastructure).
The COVID-19 pandemic has prompted firms to consider nearshoring or reshoring, re-evaluating their global networks and recognizing hidden costs related to non-economic macro attributes (government incentives, environmental regulations, IP protection). Managers face challenges in aligning multilevel information, especially in SMEs and MNEs, which deal with diverse international markets and resource constraints.
Multilevel theory indicates that misalignments can lead to inaccuracies in specifying location constructs, acquiring comprehensive information, and structuring decision-making processes. This includes: a) Knowledge gaps on multilevel relationships for location movements, b) Lack of structured decision-making, c) Difficulty in acquiring precise location attribute information.
The thesis addresses these issues through four papers:
1. A literature review identifies dominant multilevel determinants and their relationships.
2. The second and third papers explore decision-making challenges using experiments and managerial interviews.
3. The final paper examines the impact of information volume and variety on managerial decision outcomes through simulation-based experiments.
Findings highlight critical relationships between macro capabilities (production, institutional, technological factors) and micro-level priorities (cost implications, quality). The research shows that more information isn't always better, identifying an optimal information volume for decision satisfaction. This study contributes to GFLD and multi-attribute decision analysis (MADA), emphasizing multilevel paradigms for offshoring and reshoring, challenging previous economic assumptions, and providing practical insights for firms and policymakers
Multi-coral reconstructions give new perspectives on Southwest Pacific oceanographic variability under anthropogenic forcing
No full textThe Southwest Pacific region, integral to understanding global climate dynamics due to its pronounced interannual to interdecadal variability, has been under-monitored by instrumental observations before the satellite era. To address this gap, proxy data from long-lived tropical corals are essential as they compensate for the late start of instrumental observations and provide insights into past oceanographic variability. Despite advancements from the current proxy-based state of the art, gaps remain related to regions such as the Western Pacific Warm Pool and understanding of hydrological and interannual variability in the South Pacific Convergence Zone (SPCZ). This thesis aims to further the knowledge of interannual to century-scale changes in the South Pacific Convergence Zone (SPCZ) position and climatology and how they may respond to global climate change. By utilizing coral proxies, it seeks to elucidate past sea surface temperature (SST), sea surface salinity (SSS), ocean acidification trends, and coral responses to changing carbonate chemistry for a multifaceted approach in describing the SPCZ region. New, monthly-resolved coral-based time series from Rotuma, Fiji, and Nomuka Iki, Kingdom of Tonga, extending back to pre-industrial baselines to 1821 and 1848, respectively, extend the geographical coverage of the South Pacific coral network.
Monthly-resolved Sr/Ca and reconstructed δ18Oseawater (sw) from paired Sr/Ca and δ18O measurements from previously undocumented island of Rotuma indicate a significant warming trend of up to 1.45 °C in the Western Pacific Warm Pool since the beginning of the 20th century. Reconstructed δ18Oseawater (sw) from paired Sr/Ca and δ18O show that the low salinity water (“fresh”) pool of the SPCZ has been extending over the last century as the Tonga coral records a freshening trend. These findings highlight the robustness of coral-based reconstructions in capturing reef to regional conditions, despite challenges posed by thermal stress events in very warm environments such as the Warm Pool that can disrupt the Sr/Ca-SST relationship. The newly generated coral-based time series in this work serve to join other SPCZ coral records in constructing of composite indices (SPCZcoral indices) to describe the regional trends and reconstruct past interannual variability. SPCZcoral indices were developed from coral geochemical time-series across multiple locations (Rotuma and Savusavu islands (Fiji), Nomuka Iki Island (Tonga), and Rarotonga). These indices extend instrumental SSS records by approximately 100 years and improve the resolution of past composite SST and SSS reconstructions of the region. They document a consistent warming trend of 1 °C and a freshening of 0.42 practical salinity units (SP) since the 1880s SPCZ wide. They offer new insights into the impact of interannual variability on the South Pacific Convergence Zone by showing differential responses between Eastern and Central Pacific El Niño episodes and reconstructing past SPCZ zonal events that bring droughts to island nations. As this thesis aims to provide a comprehensive overview of potential anthropogenic influences on the oceanographic variability of the SPCZ region, impacts of ocean acidification (“the other CO2 problem”) were explored through δ11B records as a proxy for seawater and coral calcifying fluid pH. Coral records from Rotuma and Tonga resolved annually to approximately biennially, dating back to 1821 and 1777, respectively, document a clear decline in pH since the late 19th century. Coral adaptive responses to increasing acidity were examined through calcifying fluid carbonate chemistry reconstructions from paired B/Ca and δ11B measurements. Despite the unfavorable conditions as reconstructed from the coral from Tonga, the coral has displayed resilience, and maintained growth rate, thus suggesting potential mechanisms for adaptation to ongoing environmental stressors. Rotuma shows a reversal of the falling pH trend since mid-20th century, which shows potential reversal of the region from a sink into a source of CO2 to the atmosphere due to observed warming of the Western Pacific Warm Pool region in the past few decades. The results warrant caution in using coral δ11B for studying open ocean acidification as local drivers add to the secular seawater pH trends and can have a varying magnitude of influence over the δ11B isotopic signature preserved in coral skeletons.
Collectively, the findings presented in this thesis converge to describe the multiple facets of changing conditions in the SPCZ in the past approximately 200 years. From observing local changes in coral locations, to the SPCZ wide changes with compositing approach, they underscore the critical role of coral proxies in climate reconstructions, particularly in regions with sparse instrumental data. Certain caveats and challenges remain in coral-based geochemistry and reconstructions, especially relating to coral metabolic imprints on proxies and the richness of local environmental conditions they might be recording, not captured by regional gridded instrumental datasets or in-situ measurements of any kind. This body of work contributes to the field of paleoclimatology by providing new coral-based records from the SPCZ, and specifically the WPWP area, extending historical climate records of the SPCZ and improving our understanding of the natural variability and anthropogenic impacts on the Earth's climate system
A toxic triad: Aggression, anger, and authoritarianism - A study with multiplayer online battle arena game players
No full textPrevious research on players’ toxic behaviors in multiplayer online battle arena games (MOBAs) has suggested that individual beliefs about how other players “ought to behave” are major contributors to how they perceive and experience toxicity. In this study, we operationalized a psychometric measure of
authoritarianism as a proxy for capturing players’ beliefs about the rigidity of roles and behavioral expectations in the MOBAs League of Legends and Dota 2. Using reasoning from frustration-aggression theory, we formulated hypotheses which we tested with a cross-sectional sample (N=216). The results offered support for our hypothesis that those scoring higher on authoritarianism also reported experiencing higher levels of anger and aggression in MOBAs. This study is among the first to offer empirical support that strong beliefs about rigid roles and behavioral patterns may lead to increased frustration and, consequently, toxic behavior.233
Bilanz und Perspektiven der Förderprogramme für Alleinerziehende in Bremen : [Policy Brief]
No full textHyperverzweigtes Polyglycerol als Basis des Festkörperelektrolyten für Lithium-Ionen-Sekundärbatterien
No full textPolymerbasierte Festkörperelektrolyte sind vielversprechende Materialien für die Weiterentwicklung der nächsten Generation von Lithium-Ionen-Batterien (LIBs). Sie versprechen eine höhere Sicherheit, eine verbesserte Energiedichte und eröffnen neue Möglichkeiten für die Entwicklung kompakterer sowie leistungsfähigerer Zellkonzepte.
Diese Arbeit befasst sich mit den synthetischen Herausforderungen eines konzeptionell neuartigen hyperverzweigten, vernetzbaren Polymerelektrolyten und dessen Anwendung in Lithium-Metall-Batterien (LMBs). Zu diesem Zweck wird zu Beginn die Synthese von hyperverzweigtem Polyglycerol mit einstellbarem Methylierungsgrad (hbPG-OHx/OMey) beschrieben. Durch die Verwendung unterschiedlicher Mengen Dimethylsulfat (DMS) in der Synthese wurden Methylierungsgrade (DM) von 0 % bis 98 % erreicht. Die Verwendung von DMS als Alkylierungsmittel und eines Mischbett-Ionenaustauschers zur Aufreinigung erwies sich als vorteilhaft und effizient. Die proportionale Beziehung zwischen dem DM und der verwendeten DMS-Konzentration sowie der direkte Einfluss der Methylierung auf die assoziativen Wechselwirkungen, insbesondere die von Wasserstoffbrückenbindungen, konnten mit spektroskopischen Methoden gezeigt werden.
Auf dieser Grundlage wird ein weiterführender Syntheseansatz für multifunktionelle, vernetzbare, hyperverzweigte Prepolymere mit maßgeschneiderten Methylierungs- und Methacrylierungsgraden (hbPG-MAx/OMey) bei vollständiger Umwandlung aller Hydroxylgruppen vorgestellt. Der Einbau von Methacrylatgruppen in das Polymergerüst wurde durch Veresterung mit Methacrylsäureanhydrid, Triethylamin und 4-Dimethylaminopyridin erreicht. Schließlich wurden die reaktiven Prepolymere mit Methacrylatsubstitutionsgraden (DS) von 5 %, 13 % und 26 % nach Zugabe eines Photoinitiators photochemisch polymerisiert, was zu mechanisch stabilen Proben führte. Dynamisch-mechanische Analysen (DMA) zeigten, dass Prepolymere mit einem höheren DS nach der UV-Polymerisation eine höhere Vernetzungs-dichte und folglich ein größeres Speichermodul sowie eine höhere Glasübergangstemperatur (Tg) aufweisen.
Schließlich wurde die Kombination der hbPG-MAx/OMey-basierten Prepolymere mit Lithiumbis(trifluormethylsulfonyl)amid (LiTFSI) und unterschiedlichen Vernetzungsgraden auf ihre Einsatzfähigkeit in LMBs als Feststoff-Polymerelektrolyt (SPE) untersucht. Eine hohe Vernetzungsdichte erhöht zwar die mechanische Integrität, verringert aber gleichzeitig die lokale Kettenbewegung und damit die Ionenleitfähigkeit. Starke Wechselwirkung zwischen Lithiumkationen und Polymerrückgrat ließen sich nachweisen. Die entwickelte SPE mit dem niedrigsten DS wurde letztendlich für Lade- und Entladeexperimente ausgewählt
The multinational enterprise as a vehicle of institutional and technological change in the global economy
No full textThis dissertation examines the role of institutional and technological change in economic development, challenging the overly optimistic view of their positive impact on a country's economy. By integrating institutional theory and innovation studies, a theoretical framework is developed to explain the complex interrelationship between institutional, technological and economic development. Based on this framework, the possibility of developmental deadlocks is explained by the occurrence of transactional and technological uncertainty. To overcome this uncertainty, multinational enterprises are introduced as influential global actors that can trigger institutional and technological change. Through international business (IB) theory, MNEs are operationalized as agents of change capable of driving development by transferring technologies and business practices to host countries, potentially overcoming barriers to development. The three essays in this thesis look at how institutions and technologies have co-evolved in the past and how multinational enterprises can steer the direction of this evolution in terms of economic development. By focusing on green patents and reforms as well as artificial intelligence as part of the institutional and technological dimensions, the thesis applies the theoretical framework to highly relevant issues of today, adding to our understanding of how changes in the institutional and technological environment can be introduced and why they will have different developmental outcomes depending on the uncertainty that arises
Adaptive Freiheitsgrade zur gemeinsamen Steuerung assistiver Roboter
No full textRobots have become a prominent part of our daily lives, be it as a versatile tool at work or as an obedient household helper. This is especially exciting for people with physical limitations, since designated assistive robots harbour a large potential to enhance their users' autonomy and quality of life.
Following this line of thought, the field of assistive robotics introduces mechanical assistants to people who would otherwise struggle with activities of daily living.
However, this necessitates adequate and potentially personalised control methods.
Focusing on wheelchair-mounted robotic arms, this thesis discusses currently available options, evaluates directly applicable manual alternatives, and proposes a novel shared control based on adaptive degrees of freedom (DoFs).
With a participatory design, each element is developed and evaluated in close collaboration with the target group, thus allowing for appropriate integrations and realistic assessments.
For the contemporary manual analysis, users evaluated the manufacturer-provided input device in comparison to a gamepad, 3D mouse, and a command-based voice control.
Here, the participants expressed an eagerness for personalised adaptability, as well as an explicit willingness to train in the use of more complex but capable systems, such as a 3D mouse.
Heeding this, this thesis introduces the novel shared control approach of Adaptive DoFs:
A camera-based sensor system probabilistically analyses the current situation to generate the most likely directions of robot motion and maps these to the user's input device, effectively replacing the classically available cardinal DoF.
For the user, this feels like the system anticipating their next move and providing support without taking over control.
An implementation of this proposed adaptive control was thoroughly evaluated with the target group, using e.g. smart glasses, showcasing high user acceptance with a steep learning curve and high success rates
Evaluation of octocoral responses to global and local fctors: ocean acidification, warming and organic eutrophication
No full textClimate change, a global factor with ocean acidification and warming as its main consequences, threatens coral reefs worldwide. Concomitant local factors such as organic eutrophication occur simultaneously, but knowledge about the interaction between global and local factors is scarce. In addition, octocorals, including soft corals and gorgoniids, are highly under-investigated, although they are an essential functional group in reef ecosystems. This thesis aimed to evaluate the ecophysiological responses of octocorals to ocean acidification, warming and organic eutrophication simulated as dissolved organic carbon (DOC). We addressed the following research questions: 1) How does the physiology of different octocoral genera respond to simulated ocean acidification? 2) How does DOC, warming, or their interaction affect the physiology of octocorals? 3) What are the physiological responses of soft corals to prolonged warming? The approach comprised a series of aquaria experiments on octocorals spanning from 40 to 120 days. We assessed diverse metrics, including mortality, bleaching, pulsation, growth, oxygen (O2), carbon (C) and nitrogen (N) metabolism, and N-cycling bacterial community dynamics. Findings revealed that octocorals in all treatments exhibited 100 % survival and maintained growth, no bleaching and positive photosynthesis except for Xenia umbellata under prolonged warming and Pinnigorgia flava under warming and DOC addition. In particular, X. umbellata showed high tolerance to local and global factors and increased N-fixation, supporting the holobiont functioning under stress. Our findings suggest that ocean acidification, warming and organic eutrophication will have lesser impacts on soft corals than most hard corals as, according to the literature, and supports soft corals as winners under future scenarios, although they are not entirely resistant to the factors assessed. This thesis contributed insights into soft corals' ecophysiological traits and mechanisms driving their tolerance, which may be key to understanding potential shifts of coral species dominance in current and future reefs. Our findings can contribute to enhancing the incorporation of soft corals within the scope of priorities for mitigating global and local factors and for devising effective reef management and improved conservation strategies
Essays on Brand Activism
No full textThe dissertation includes 3 essays on the topic of brand activism. The first essay delineates brand activism from related constructs (such as, e.g., corporate social responsibility), summarizes existing empirical literature on brand activism, and proposes future research avenues in the context of brand activism. The second essay investigates the relation of brand activism to brand reputation on social media as well as to brand financial performance (i.e., stock price). The third essay considers consumers' reactions to different activist topics addressed by brands. Also, the third essay focuses authenticity as well as its antecedents and outcomes in the context of brand activism
Understanding and Modelling Convection with Machine Learning
No full textMachine Learning (ML) has demonstrated its potential to improve the performance of an Earth System Model (ESM), yet many challenges remain. ESMs are essential tools to project and understand climate change but have known biases. Convective processes are in general unresolved as their typical length scale is smaller than the grid size of ESMs. The effect of such subgrid processes is estimated with parameterizations, that are often attributed to be sources of biases in ESMs. A way to reduce these limitations of ESMs is to take advantage of ML or deep learning (DL) algorithms that learn actively on output from convection permitting high-resolution simulations which explicitly resolve convective processes. The resulting ML parameterizations are then coupled with an ESM and replace existing traditional subgrid parameterizations in hybrid (physics + ML) ESMs. This thesis presents novel approaches to transform DL algorithms from data science concepts towards an operational use in ESM simulations. First, a DL algorithm is developed that enables to better understand subgrid convective processes and interactions with the large-scale environment. Specifically, the latent space of a Variational Encoder Decoder (VED) reveals the meridional temperature differences between the tropics and poles together with the characteristics of subtropical and subpolar air masses along the mid-latitude storm tracks are key drivers of convective processes. Moreover, the VED separates key characteristics of shallow convective, cumulus, cirrus-like and deep convection regimes. Second, a novel DL algorithm ensemble approach is developed, that provides an improved representation of convective processes. Third, it is demonstrated that the more realistic uncertainty quantification of the ensembles capturing the chaotic nature of subgrid processes stabilizes hybrid simulations and reduces longstanding biases in a hybrid model run of an ESM. This thesis thus advances the modelling of convective processes with DL in Earth system sciences via enhanced representation and understanding of convective processes in ESMs. It provides ways to reduce limitations of state-of-the-art ML models and paves a way forward to the operational use of DL and ML in the next generation of ESMs