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Kinetische Stabilisierung von niedervalenten Hauptgruppen-Verbindungen
No full textHighly reactive species, such as cations and radicals, are often proposed as intermediates in reaction mechanisms. The stabilization and isolation of such species is an ongoing challenge in chemistry. In this work a plethora of bis-substituted meta-terphenyl element compounds of group 13, 15 and 16 were synthesized and the first kinetically stabilized indinium ion (2,6-Mes2C6H3)2In+ as a 4 valence electron species, the first kinetically stabilized stibenium and bismuthenium ion (2,6-Mes2C6H3)2E+ (E = Sb, Bi) as 6 valence electron species and the first kinetically stabilized tellurenyl radical cation (2,6-Mes2C6H3)2Te*+ as a 7 valence electron species were successfully synthesized and fully characterized, opening a new area of compound classes
The entrepreneurial journey of refugee entrepreneurship – resilience and embeddedness issues
No full textThis cumulative dissertation explores the dynamic nature of resilience and the embedding process of refugee entrepreneurs. Due to the 2015 global refugee crisis, policymakers and academics have started paying attention to refugees' entrepreneurial potential. Compared to migrants, refugees face significant adversities due to forced displacement, such as psychological trauma, severe resource disadvantages, and substantial institutional barriers. Consequently, refugee entrepreneurs need to develop and maintain a high resilience and embedding process when integrating into the new host country. However, research on refugee entrepreneurial dynamic resilience and the embedding process remains unexplored. A few preceding studies have treated resilience as a mere personal trait of refugees and overlooked its dynamic aspect. This dissertation addresses these research gaps and explores the multi-layered nature of resilience and the embedding process in refugee entrepreneurship. It contributes to recent discussions on refugee entrepreneurial resilience and embeddedness by theorizing it as a dynamic process that takes into account both the home and host country contexts
Korrekturen im Diskurs
No full textDie Arbeit untersucht mit diskurslinguistischem und koloniallinguistischem Fokus das sprachliche Mittel der Korrektur. Es geht dabei um Sprache in kolonialen Machtverhältnisse und wie Korrekturen zu der sprachlichen Kolonisation während der faktischen deutschen Kolonialzeit beigetragen haben
SPiraling Intelligent Robotic Underwater monitoring pLAtform (SPIRULA) - towards repeated, high density and low-cost seafloor monitoring
No full textRepeated multi-modal seafloor observations over an extended period of time have significant applications in marine biology, chemistry and geology. Reducing the logistical effort, cost and complexity in monitoring technology for such tasks, will help to increase accessibility and availability of relevant long-term monitoring data. To this end, a new design concept, the SPiraling Intelligent Robotics Underwater monitoring pLAtform (SPIRULA), is introduced and evaluated. The key idea for SPIRULA is the combination of a static lander and a mobile autonomous vehicle, which is permanently tethered to the lander. Through shared data and energy between the two sub-systems SPIRULA can be made robust, small and with reduced complexity. By unwinding and winding from a passive drum with a taught tether the SPIRULA vehicle is forced on a circle involute path around the SPIRULA lander, which can be analytically described and used during system design and for navigation purposes. Spiraling paths have shown to be efficient in terms of coverage, for instance, a tether length of approximately 20 m allows already for a monitoring coverage of 1200 m2 around the lander. Given a conservative estimate of the energy expenditure of the SPIRULA system and a desired survey area of 1200 m2 at a constant speed along the path of 0.5 m/s it can be shown, that a total energy storage of 10 kWh would provide the system with the ability to conduct between 38 to 82 surveys depending on the sensor suite used. Those surveys can then be spread over days to months to provide a first step towards repeated long-term environmental monitoring on the seafloor with SPIRULA.German Marine Research Alliance (DAM) research mission ‘Marine carbon sinks in decarbonization pathways’
The Health Care System in Uruguay
No full textThis country report provides a description of the emergence of a health care system under public responsibility in Uruguay. The inception of the health care system refers to the first legislation stipulating entitlements to medical care. The report also includes a brief description of major health care reforms, and the current organization of the health care system in Uruguay. This report is part of the CRC 1342 Social Policy Country Briefs Series.Deutsche Forschungsgemeinschaft (DFG)3
Debattieren, Opponieren, Protestieren – Interdisziplinäre Perspektiven auf sprachliche Praktiken des Widersprechens
No full textPublikation der U Bremen und U Wien internationalen Studierendenkonferenz »Debattieren, Opponieren, Protestieren – Interdisziplinäre Perspektiven auf sprachliche Praktiken des Widersprechens« 2023
Abstrakte Verhaltensmodellierung und Zustandsüberwachung integrierter Schaltungen hinsichtlich Umgebungs- und Degradationseinflüssen
No full textDie technologischen Fortschritte bei der Herstellung moderner integrierter Schaltungen ermöglichen die Fertigung in immer kleineren Strukturgrößen, die mit signifikanten Steigerungen der Leistung und Effizienz einhergehen. Die geringen Strukturgrößen bringen jedoch auch Herausforderungen mit sich, da sie sehr anfällig gegenüber Störeinflüssen wie Prozessvariation, Spannungs- und Temperaturschwankungen sowie Alterung sind. Diese Faktoren, die als PVTA bezeichnet werden, können die Funktionalität der Schaltungen während des Betriebs beeinträchtigen.
Daher ist für die Entwicklung zuverlässiger Schaltungen eine frühzeitige Berücksichtigung dieser Einflüsse im Entwurfsprozess unabdingbar. Die Simulation dieser Effekte ist, aufgrund der zu berücksichtigenden physikalischen Abhängigkeiten, meist lediglich auf einem geringen Abstraktionsniveau wie der Transistorebene möglich. Für große Systeme ist diese Art der Simulation jedoch angesichts der Komplexität und des damit verbundenen Rechenaufwands nicht praktikabel, so dass eine Betrachtung auf höheren Abstraktionsebenen erforderlich ist.
Dafür werden Modelle und entsprechende Modellierungsmethoden benötigt, welche in der Lage sind, die relevanten Eigenschaften und Abhängigkeiten der betrachteten Schaltungskomponenten darzustellen. Trotz der Berücksichtigung der möglichen Einflüsse und Verwendung von Sicherheitsmarge im Entwurfsprozess kann es während des Betriebs zu Veränderungen des Schaltungsverhaltens kommen, was insbesondere in sicherheitskritischen Anwendungsfeldern von höchster Relevanz ist. In diesen Fällen können zusätzliche Monitoringstrukturen Aufschluss über den aktuellen Zustand der Schaltung und über mögliche Veränderungen geben.
Diese Arbeit konzentriert sich in diesem Zusammenhang auf zwei Themen: die Entwicklung einer neuartigen Modellierungsmethode für stochastische Verhaltensmodelle und die Untersuchung einer Monitoring-Methode für die Überwachung analoger Schaltungen. Die Modellierungsmethodik befasst sich mit der Erstellung von stochastischen Verhaltensmodellen unter Verwendung von Response-Surface-Modellen (RSM), die die stochastische Verteilung von Schaltungseigenschaften aufgrund von Prozessvariationen, Umgebungsbedingungen und Alterung berücksichtigen. Verschiedene Methoden, einschließlich der Erfassung von Variationen der Normal- und Lognormalverteilung und der Modellierung nicht-normalverteilter Variationen, werden entwickelt und durch Simulationen an verschiedenen Beispielschaltungen analysiert.
Im zweiten Teil der Arbeit wird ein Monitoring-Verfahren untersucht, welches die Koeffizienten digitaler adaptiver Filter zur Überwachung des Zustands analoger Schaltungen nutzt. RSM-basierte Verhaltensmodelle werden eingesetzt, um das Referenzsignal des idealen Schaltungsverhaltens zu erzeugen. Das Monitoring-Verfahren erlaubt zudem die Überwachung der Degradierung der Schaltung bei fortschreitender Alterung. Das Verfahren wird anhand von Simulationen sowie einer messtechnischen Auswertung einer Beispielschaltung untersucht
Towards sustainability in the coastal blue economy: Navigating institutional change for coastal resource co-management in Ghana
No full textThis thesis examined the challenges of the governance change in coastal fisheries in Ghana. It investigated the role of contextual and process dynamics in the outcomes of fisheries co-management arrangement. Specifically, it examined the process through which the transition to co-management was implemented in coastal fisheries in Ghana and why the institutional arrangement could not be sustained. The thesis is presented as a cumulative dissertation made up of three interrelated papers. The first paper (paper 1) is more conceptual, reviewing theories of institutional change and their applicability to the study of governance change in coastal marine systems. The second paper (paper 2) is an empirical paper that examined the process of institutional development for collaborative coastal resource governance. Paper 3 examined the role of contextual political-economic dynamics in the challenges of developing and sustaining co-management arrangements in coastal fisheries. The thesis adopted analytical perspectives from three institutional theories: ideational theory, legal pluralism and the political settlements theory. Methodologically, the research adopted a qualitative approach, using semi-structured interviews and focus group discussions to collect data from relevant stakeholders in coastal fisheries in Ghana. Secondary data was also a valuable source. The thesis finds that a concatenation of contextual socio-political dynamics, institutional and ideological path-dependencies hindered the governance transformation in coastal fisheries in Ghana. It makes a theoretical contribution to the institutional analysis of co-management, making the argument that outcomes of co-management regimes should not only be evaluated in terms of how such institutional arrangements produce socio-economic and ecological sustainability outcomes but also in terms of institutional sustainability. It emphasises that to understand the challenges of sustaining co-management regimes to produce sustainable governance outcomes, particular attention should be paid to the process of institutional change and contextual socio-political, ideological and institutional dynamics within which co-management arrangements are designed and implemented. The thesis underscores the need for a broader consideration of the socio-political and institutional dynamics of the resource context in governance transformation processes for sustainability in the coastal blue econom
Towards a Knowledge Engineering Methodology for Flexible Robot Manipulation in Everyday Tasks
No full textIn the last decade, there have been great advancements in household robotics, enabling robots to autonomously accomplish household tasks. These robots are typically programmed for specific tasks and/ or objects. We hypothesise that the lack of flexibility in fulfilling new ad-hoc task requests can be overcome by a knowledge-based approach, allowing robots to infer how to address a new task or carry out known tasks on new objects.
Towards this goal, we propose a knowledge-based methodology that leverages knowledge already existing on the web to construct an ontology supporting robots in reasoning about parameters that influence manipulation actions for execution of task variations on a range of objects. The ontology comprises object and action
information, covering dispositions and affordances as well as task-specific properties. As a proof-of-concept, we manually construct a food-cutting ontology by importing and linking knowledge from relevant ontologies in addition to extracting and semantically enhancing knowledge from unstructured web sources. We demonstrate how robots can query the ontology and translate the contained information into action parameters. We evaluate the feasibility of the created ontology by simulating a robot accessing the ontology for parameterisation of actions to perform task variations of cutting
Advances in Algorithmic Meta Theorems
No full textTractability results for the model checking problem of logics yield powerful algorithmic meta theorems of the form:
Every computational problem expressible in a logic ℒ can be solved efficiently on every class C of structures satisfying certain conditions.
The most prominent logics studied in the field are (counting) monadic second-order logic (C)MSO and first-order logic FO and its extensions. The complexity of CMSO model checking in general and of FO model checking on monotone graph classes is very well understood. In recent years there has been a rapid and exciting development of new algorithmic meta theorems. On the one hand there has been major progress for FO model checking on hereditary graph classes. This progress was driven by the development of a combinatorial structure theory for the logically defined monadically stable and monadically dependent graph classes, as well as by the advent of the new width measure twinwidth. On the other hand new algorithmic meta theorems for new logics with expressive power between FO and CMSO offer a new unifying view on methods like the irrelevant vertex technique and recursive understanding. In this paper we overview the recent advances in algorithmic meta theorems and provide rough sketches for the methods to prove them.2:12:2