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The present study deals with the phenomenological observation of the corrosion of the positive electrode foil of lithium-ion batteries containing LiNi0.6Co0.2Mn0.2O2 (NMC) as cathode material. Due to the presence of moisture, localized water accumulation is formed on the NMC surface. The water absorbed by the electrolyte reacts with the NMC under Li+/H+ exchange and the resulting pH increase leads to dissolution of the carrier foil and characteristic salt-like blooms on the NMC surface. With the increase in the relative area occupied by the holes in the aluminum foil per time, a sufficiently suitable parameter was found with which to quantitatively determine the extent of corrosion. The degree of degradation depends on time and ambient humidity. It was shown that functional recycling with the water jet method is no longer applicable for degraded foils, since the mechanical stability of the foils decreases as corrosion progresses. Lithium, aluminum, sulfur and oxygen were detected in the blooms using SEM–EDX and Laser-Induced-Breakdown-Spectroscopy (LIBS). The underlying NMC layer was found to contain mainly aluminum and significantly lower lithium content than the non-degraded material. SEM and Raman microscopy analyses also showed that the active material is also locally degraded and therefore no longer suitable for functional recycling.
Possible synergy between FLEGT-VPA & REDD+ towards improving forest governance framework in Cameroon
(2023)
Illegal logging is seen as a serious impediment to achieving sustainable management of forests in the tropics. In addition, deforestation contributes in increasing carbon dioxide emissions in the atmosphere, resulting to biodiversity loss and climate change. Illegal logging and deforestation have affected Cameroon’s forest ecosystem negatively since the mid-1980s as a result of the economic crises, which intensified the exploitation of forest resources for multiple purposes. In response, some policy initiatives came up such as FLEGT-VPA and REDD+ to fight against the threats. It is due to the above background that this study was designed to examine the possible synergy between FLEGT-VPA and REDD+ towards improving the forest governance framework in Cameroon. The first part of the study assesses FLEGT-VPA in Cameroon with the application of interviews of key informants who were involved in the negotiation process of the EU-Cameroon Voluntary Partnership Agreement. The second part of the study assesses the management of Bimbia Bonadikombo Community Forest (BBCF), as one of the REDD+ pilot project sites around Mount Cameroon in the South West Region of Cameroon. The use of surveys, content analysis, and observations seeks to assess these two initiatives in their role in improving forest governance in Cameroon. The first part of the research reveals that since Cameroon ratified the FLEGT-VPA in 2011, there has been progressed concerning stakeholder participation in forest-related issues. Again, the study also reveals challenges faced with the setting up of a system to verify timber from legal origin as recommended by the European Union. The research further reveals a lack of commitment by the government in revising the current forest policies and re-organizing the domestic market for timber trade as part of the commitment made by the government during the ratification of the FLEGT-VPA. The second part of the study finds that the management of BBCF is not governed by the provision of the Cameroon community forestry manual or by its bylaws posing doubts if community forestry can halt emissions of greenhouse gases caused by deforestation, thus helping REDD+ achieve its objectives. The study recommends the need for rapid policy reform and a cross-sectoral transformation to enable FLEGT-VPA and REDD+ to synergize for a better policy outcome on issues concerning forestry and climate change.
The next generation of civil turbofan engines targets the by-pass ratios of up to 20:1, requiring an innovative fan design with a low fan pressure ratio, low specific thrust and a radically increased fan diameter. The aerodynamic stability of such a large slow rotating fan is very sensitive against the back-pressure variations in the by-pass duct, especially during the take-off operations. The back-pressure regulation can be achieved significantly through a Variable Area Fan Nozzle (VAFN). This work deals with the design development of VAFN concepts for ultra-high by-pass ratio engines which was researched in EU funded program ENOVAL and received funding under grant agreement number 604999.
A system engineering approach was implemented for the VAFN development by following the requirements in conceptual, preliminary and detailed design phases. The design domains in the rear nacelle and under the core fairing were selected for the concept generation. Several qualitative and quantitative trade studies were conducted to down-select the best-fit solution during each design phase. These included the kinematic simulations of various types of VAFN modulations; analytical calculations to understand the thermodynamics of the selected VAFN kinematics; aerodynamic performance predictions using CFD simulations on a large number of preliminary designs; 3D CFD simulations for detailed performance assessments including the design optimization of individual features and distortions due to failed modulations; and FEM calculations for the topology generation and optimization of structural components. The overall weighted effect was determined for each output parameter and the results were presented in percentile changes relative to that with a fixed nozzle reference geometry.
Two VAFN concepts were selected for the final detailed design phase, Flaps in rear nacelle domain and Variable Inner Fairing Structure (VIFS). Both concepts showed better outputs in terms of specific fuel consumption, noise emission and fan’s safety margin during the take-off, with an over-area exhaust position than those with a fixed nozzle operation. During the climb phase, with an under-area VAFN position, both concepts resulted in drawbacks due to higher aerodynamic losses relative to the fixed nozzle. During MCR, both the VAFN concepts with stowed positions caused losses mainly due to leakages and higher structural weights relative to the fixed nozzle configuration. For each VAFN concept, a detailed system definition was developed and the function trees for each operation were explained. A discrete modulation type with two positions was described and recommended for both concepts. This included an over-area deployed position for the take-off phase and a stowed position for the rest of the flight, based on the beneficial performance of the VAFN concepts over the fixed clean nozzle configuration.
The creation of adequate simulation models for complex assemblies is an extensive process that requires a lot of experience, and on the other hand involves a multitude of manual, tedious tasks. These are significant obstacles for improving the process performance and capabilities. The objective of this research is to develop methods which digitally imitate the way of thoughts of the engineer in the design process towards a digital system understanding and which support the automation of the involved manual workflow.
This thesis presents a strategy to translate engineering reasoning and actions to an equivalent in the computer domain. A cardinal step is to gain understanding of system arrangements, boundary conditions and its components. Based on this evaluation, the identification of assembly parts is forming the foundation for optimized process chains for the transfer to the analysis environment. Model complexity relates to computational effort, which in turn affects model capabilities and manageability. To achieve a satisfactory compromise of model quality and complexity, this transfer process is strongly dependent on the visual analysis, reasoning and manual implementation of skilled engineers.
The principle of translating engineering logics is pursued from the assembly system to its smallest parts. Component segmentation methods allow subdividing regions of interest into substructures which are assigned with a feature vector. This vector comprises metrics describing the substructures with regard to specific aspects and is the key decision point for subsequent steps as idealization, suitable Finite-Element modeling and ultimately building an analysis model. The created system database is continuously maintained and supports these process chains as well as the final setup of the assembly simulation model.
An automated workflow like this implies advantages for efficiency, but also creates opportunities for further use cases. This workflow has been exploited for generating a training data set from the different simulation variants as a basis to a knowledge representation imitating engineering experience. An algorithm from the graph neural network field is applied to this data set as a conceptual approach. The intention pursued in this concept is to model the learning progress about estimating the influence of modelling decisions on simulation results and quality.
This research proposes a holistic strategy and describes methods to achieve the objectives of decreasing manual effort, introducing an automated and geometry-based process and digitally replicating engineering experience by introducing a knowledge database.
Assessing authenticity in heritage conservation : case study : architectural conservation in Bahrain
(2023)
The thesis complements the authenticity discourse in heritage conservation with the perspective of laypeople and evaluates the pertinent methodology for the application of the normative concept in architectural heritage conservation. Based on the Nara Document on Authenticity, the Operational Guidelines for the Implementation of the World Heritage Convention anchor the concept in the credibility and truthfulness of internal and external factors – referred to as information sources – that communicate a heritage site’s cultural values. Conversely, the author explored the truthfulness of messages conveyed to site users in a qualitative research based on interviews focused on two urban reference sites in Bahrain. These stand for different eras and conservation approaches: the ensemble of colonial-style governmental buildings at Bab al-Bahrain in Manama and the vernacular Siyadi Shops in the market area Suq al-Qaisariya in Muharraq, which were restored in the course of a World Heritage nomination. The interpretive content analysis compares how architects and non-architects, who represent laypeople in architectural conservation, perceived their authenticity and also traces cultural contingencies. The empirical data confirms pronounced differences in the way architects and non-architects perceive authenticity but only a few between representatives of so-called Western and Eastern cultures. Assessed against international heritage conservation standards, the site in Muharraq proved more authentic than the one in Manama. However, the meanings produced in the interaction between the sites and the interviewees proved be of limited truthfulness in both cases. A key finding is hence that a constructivist authenticity concept can serve no normative function when heritage conservation is considered a discipline at the service of historiography. While all potential factors of authenticity as per the Nara Document proved to be relevant, perceived material authenticity was found to be an outstanding reason why the site in Muharraq was appreciated more. Its rehabilitation was found to successfully reconcile essentialist and constructivist authenticity understandings by paying tribute both to the documentary value of the historic site and to the experiential needs of its users. The findings support the ICOMOS Venice Charter’s material-focused approach while confirming the relevance of a broadened authenticity understanding and highlighting the importance of integrated, participatory approaches to heritage conservation. By illustrating the importance of expertise when assessing the authenticity of architectural heritage, the findings at the same time flag limits to democratizing architectural conservation practice. The author recommends developing practice-oriented guidance for the assessment of authenticity of heritage sites based on further research and to add interpretation facilities to the list of factors of authenticity.
In the summer term 2020 the Chair of Urban Management, BTU Cottbus-Senftenberg, conducted an excursion for Master students of planning and architecture to the region on both sides of the border between Romania and Serbia in a format of distance learning. Over three days the students and local experts of various professional backgrounds engaged online in discussion on urban development in Timișoara, Novi Sad and Belgrade. We explored how the dynamics of changing physical and social boundaries shape urban territories in a tension between centrality and periphery, while also engaging with the paradigm shift in planning centred on culture and people’s participation, as well as anticipations from flagship culture schemes to trigger positive urban changes. This publication provides summaries of some of the contributions, illuminating urban development as a complex process which involves a plurality of geopolitical shifts, engaged actors, interests, perspectives, hope-filled approaches and instruments.
This thesis deals with strategies for achieving high data throughput in wireless sensor networks that use a time division multiple access (TDMA) scheme to resolve medium access. The thesis uses a multi-sided approach that deals not only with the scheduling algorithm but also with the network layer and the interference model. The thesis proposes four solutions that significantly improve data throughput, fairness, and latency in the considered scenario.
The thesis starts with an overview of state-of-the-art medium access control (MAC) protocols, emphasizing TDMA. Based on this overview, it is concluded that not much space for improvement is left in the field of schedule calculation algorithms; many such algorithms are proposed up to date, and they can achieve schedule lengths close to the theoretical minimum. However, the research also reveals a lack of in-detail evaluation and comparison of these algorithms; this makes choosing the most suitable algorithm for a particular application hard and performance estimation inaccurate. Therefore, an extensive evaluation of state-of-the-art TDMA protocols using simulations and over 200 randomly generated networks was performed to tackle this issue. The results allow choosing an appropriate algorithm and estimating performance for each specific application.
Next, the problem of multiple packet transmissions during a single time slot is analyzed. State-of-the-art TDMA protocols assume that one packet can be transmitted in each slot and optimize the number of slots each node gets under this assumption. However, when nodes can transmit more than one packet, the performance of such a schedule is impaired. To solve this, the M-TreeMAC protocol is proposed; this protocol considers the actual number of packets transmitted in a time slot and optimizes the schedule accordingly. Furthermore, it is observed that the routing topology heavily impacts the schedule length created using this algorithm; an algorithm that optimizes the topology to result in the shortest schedule when M-TreeMAC is used is proposed, increasing benefits even further.
Finally, the accuracy of the 2-hop interference model, commonly used by state-of-the-art TDMA scheduling algorithms, is studied and simulated using a realistic radio model based on measurement results. The results show high packet loss ratios for packets traveling a large number of hops to reach the sink. The adaptive interference model is proposed to improve the 2-hop interference model. The proposed model can increase throughput significantly in networks with a height of ten or more hops.
In dieser Dissertation wurden Zuverlässigkeitsaspekte der NED-Aktoren betrachtet und ihre Langzeitstabilität untersucht. Die Langzeituntersuchungen an einzelnen NED-Aktoren haben gezeigt, dass insbesondere große elektrische Felder zur Verkürzung der Lebensdauer der Aktorik führen können. Elektrische Felder beschleunigen Oxidation der NED-Siliziumelektroden. Dabei wurden zwei unterschiedliche Oxidationsmechanismen beobachtet: die anodische Oxidation von Siliziumelektroden im Isolatorbereich und die feldemissionsunterstützte Oxidation. Die beiden Degradationsmechanismen begünstigen das Wachstum des Siliziumoxides an Siliziumelektroden und resultieren in der Veränderung der Oszillationseigenschaften der NED-Aktoren mit der Zeit. Weitere Untersuchungen an den NED-basierten Anwendungen – Mikrolautsprecher haben verdeutlicht, dass solche Faktoren wie Feuchtigkeit die Degradation am meisten forcieren. Durch Passivierung der Aktoren, wobei sie z. B. mit Aluminiumoxid im ALD-Verfahren verkapselt werden, können unerwünschte Degradationsmechanismen deutlich verlangsamt werden. Durch eine geeignete Materialwahl bei der Verkapselung kann sogar gleichzeitig die Effizienz der Aktoren verbessert werden.
Das Phänomen Hatespeech gewinnt zunehmend Aufmerksamkeit in der Öffentlichkeit und in der Forschung. Das ist insofern wichtig, weil Hass, Hetze und Diskriminierung gegenüber Menschen, die einer bestimmten Gruppe zugeordnet werden, vor allem über Informations- und Kommunikationstechnologien eine gesamtgesellschaftliche Verrohung zur Folge hat. Hatespeech schränkt die Meinungsvielfalt ein und bedeutet eine Bedrohung für die Demokratie. Sie stellt jedoch kein reines Netzphänomen dar, sondern basiert auf real existierende Macht- und Diskriminierungsstrukturen. Das Phänomen einzudämmen, ist die Intention verschiedener Stiftungen und Initiativen. Hatespeech ist jedoch allgegenwärtig und selbst in der Schule verbreitet. Sie stellt damit eine Gefahr insbesondere für junge Heranwachsende und weiterführend für das alltägliche Schulleben dar. Somit stellt sich die Frage, welche Mittel der Institution Schule zu Verfügung stehen, um dem Phänomen wirksam entgegenzutreten. Im Zuge von präventiven und interventiven Maßnahmen stehen schulbezogene Programme im Vordergrund. Die vorliegende Masterthesis befasst sich daher mit einer ersten Bestandsaufnahme von deutschsprachigen, schulbezogenen Programmen zur Prävention und Intervention bei Hatespeech unter Kindern und Jugendlichen (Jahrgangsstufen 5 bis 12). Insgesamt konnten 14 entsprechende Programme im Rahmen der Recherchearbeit identifiziert werden. Diese wurden auf ihre Inhalte und Durchführungsmodalitäten sowie anhand von fünf ausgewählten Qualitätskriterien analysiert und hinsichtlich ihrer Anwendung in der schulischen Praxis beschrieben und erörtert. Die Übersicht über Schwerpunkte, Stärken sowie Entwicklungspotentiale schulbezogener Hatespeech-Programme soll eine informierte Entscheidung über den Einsatz der Programme in der Schule und darüber hinaus in der offenen Kinder- und Jugendarbeit ermöglichen.
Die Stadt Cottbus ist seit mehreren Jahren durch extrem rechte und verschwörungsideologische Mobilisierung herausgefordert. Auch in der Covid-19-Pandemie ist Cottbus Schauplatz regelmäßiger Demonstrationen. Mit Beginn des russischen Angriffskriegs auf die Ukraine verschiebt sich der inhaltliche Fokus der sogenannten Montagsspaziergänger sukzessive weg von der Pandemie und hin zum Krieg. Die hier vorliegende Forschung wendet sich den Protestveranstaltungen zu, die im Zeitraum vom 28. Februar bis 24. Oktober 2022 in Cottbus in Reaktion auf den russischen Angriffskrieg organisiert werden und untersucht unter Anwendung der Grounded Theory ausgewählte Redebeiträge. Sie zielt darauf ab, die Inhalte und Darstellungsweisen der RednerInnen hinsichtlich der Gefahrenpotentiale einzuordnen und im Sinne anwendungsbezogener Forschung in Richtung Prävention und zivilgesellschaftlicher Gegenwehr weiterzudenken. Die Forschung zeigt: Ähnlich wie in anderen ostdeutschen Städten sind auch in Cottbus die Veranstaltungen von extrem rechten Akteuren und Gruppen dominiert; sie werden unterstützt von Teilen eines bürgerlichen Milieus der sogenannten gesellschaftlichen Mitte. Sichtbar wird außerdem: Akteure aus dem Coronaprotestmilieu haben sich weiter radikalisiert; verschwörungs- und insbesondere reichsbürgerideologische Inhalte dominieren die untersuchten Veranstaltungen und mischen sich mit prorussischen Positionen und dem Ideologem einer „eurasischen“ Neuordnung des europäisch-asiatischen Raums. Die Ablehnung „des Westens“ bildet ein wiederkehrendes Metanarrativ.
Background: Food sustainability is becoming increasingly important for the achievement of sustainable development goals, especially in light of recent global challenges of climate change, geopolitical conflict and the increasing vulnerability of food systems. The world is emphasising the importance of holistic approaches to agriculture and food systems to tackle these challenges. Germany’s Sustainable Development Strategy for 2030 associates SDGs 2, 3 12 and 15 with sustainable agriculture and food systems as crucial elements to achieve these goals. However, with the lack of knowledge in this area, and the scarcity of tools to monitor and assess food sustainability, it has become crucial to investigate potential holistic approaches and frameworks to assess the sustainability of food systems.
Purpose: This study uses the national framework of Sustainable Development Goals (SDGs), as the only available valid holistic framework, to explore the sustainability of the bread system in Germany. It operationalises the SDGs to bakery level to identify significant indicators that could, potentially, be used to assess the sustainability of artisan bakeries, and identify to which SDGs the bakeries contribute.
Methods: This study utilises a mixed-methods research design to address the multi-disciplinary nature of the food sustainability concept. It critically evaluates the SDG framework and identifies a set of indicators, which are expanded with further indicators to address the cultural dimension of bread as a cultural heritage. To collect data, a 26-item questionnaire was issued to 586 artisan bakeries with a response rate of 8.8% (n = 52); the 52 bakeries own 562 branches. This was followed by interviews with an acceptance rate of 19% (n = 10). Descriptive and inferential statistics were used to analyse the quantitative data, while the interviews were transcribed from German to English and coded using NVivo 11.
Results: Sustainable bread is redefined from a holistic perspective encompassing theory, policies and artisan bakeries. The results confirm that bakeries positively contribute to bread sustainability in Germany, as well as towards achieving the national SDGs. Progress areas include energy efficiency, sustainable packaging, local procurement, heritage promotion, waste reduction and ecolabels. Interestingly, individual bakeries appear to be slightly more sustainable than chains due to their flexibility in adapting to new practices and their use of organic products; however, chain bakeries are slightly less sustainable, but are proven to be more efficient in terms of productivity and market reach.
People in a social network are connected, and their homogeneity is reflected by the similarity of their attributes. For effective clustering, the similarities among people within a cluster must be much higher than the similarities between different clusters. Traditional clustering algorithms like hierarchical (agglomerative) or k-medoids take distances between objects as input and find clusters of objects. The distance functions used should comply with the triangle inequality (TI) property, but sometimes this property may be violated, thus negatively impacting the quality of the generated clusters.
However, in social networks, meaningful clusters can be found even though TI violates. One possibility is a quantum-logic-based clique-guided non-TI clustering approach. The commuting quantum query language (CQQL) is the base for this approach. The CQQL allows the formulation of queries that incorporate both Boolean and similarity conditions. It calculates the similarity value between two objects.
Furthermore, attributes may not have equal impact on similarity and affect the resulting clusters. CQQL incorporates weights to express the varying importance of sub-conditions in a query while preserving consistency with Boolean algebra. This enables personalization of results through relevance feedback (RF).
The main challenge of comparing clusterings is that there is no ground truth data. In such situations, human-generated gold standard clustering can be used. The question is how to compare the performance of clusterings. A noteworthy technique involves counting the pairs of objects that are grouped identically in both clusterings. By doing so, a clustering distance is calculated that measures the dissimilarity.
To validate the non-TI clustering approach, experiments are conducted on social networks of different sizes. Three central questions are addressed by the experiments mentioned: first, is it possible to find meaningful clusters even though TI violates; second, how does a user interact with the system to provide feedback based on their needs; and third, how fast do the detected clusters based on the proposed approach converge to the ideal solution?
To sum up, the experiments’ objective is to demonstrate the validity of a theoretical approach. The research findings presented here provide sufficient evidence for detecting meaningful clusters based on user interaction. Furthermore, the experiments clearly demonstrate that the non-TI clustering approach can be used as an RF technique in clustering.
The present research aims to analyze the possibilities of introducing the living “Intangible Cultural Heritage” as Supplement of Knowledge into the formal educational system particularly the Early Childhood Education in the Far North Region of Cameroon - irrespective of the 2003 Convention for the Safeguarding of the Intangible Cultural Heritage and the 2005 Convention on the Protection and Promotion of the Diversity of Cultural Expressions. This Region is purposively selected for its stronghold of multifarious and diverse ethno-cultural (id)entities and citadel of the country’s enshrined traditions. The rural area of Kolara is conveniently chosen to explore how to blend the receding ethno-cultural heritage with the formal education system in accordance with the aim of education in Cameroon and therefore could be an example of how to train citizens firmly rooted in their cultures but also opened to the world. It presupposes that the current formal primary educational system is not constructive for primary school starters. On the basis of a combination of participatory research and systematic data collection methods, three educational heritages could be outlined: the ethno-cultural traditional educations specific to the two major ethno-cultures Tupuri and Fulbé and the Islamic Arabic educational heritage peculiar to Muslims, predominantly Fulbé. In this context, it could be determined to what extend the formal education is ethno-cultural specific, environment related and learner centered.
In the time of increased awareness about the environment problems by the public opinion and also intensive international efforts to reduce emissions of greenhouse gases, as well increase of the generation of electrical energy to facilitate industrial growth, the conference offers broad contribution towards achieving the goals of diversification and sustainable development.
Focus of the student conference is to promote the discussion of views from scientists and students from Wroclaw University of Technology, Technical University of Ostrava and Brandenburg University of Technology Cottbus-Senftenberg.
The conference is a unique teaching session motivating the students to write science related papers, prepare presentations and discus future developments. It is a formal part of the curriculum offered as an elective module, accompanied by a technical excursion.
1. Erste Änderungssatzung zur Prüfungs- und Studienordnung für den Bachelor-Studiengang Bauingenieurwesen (B. Sc.) vom 21. September 2023
2. Lesefassung: Prüfungs- und Studienordnung für den Bachelor-Studiengang Bauingenieurwesen (B. Sc.) vom 04. Oktober 2022 i. d. F. der ersten Änderungs-satzung zur Prüfungs- und Studienordnung für den Bachelor-Studiengang Bauingenieurwesen (B. Sc.) vom 21. September 2023
1. Erste Änderungssatzung zur fachspezifischen Prüfungs- und Studienordnung für den Master-Studiengang Architektur vom 21. September 2023
2. Lesefassung: Prüfungs- und Studienordnung für den Master-Studiengang Architektur (M. Sc.) vom 29. September 2022 i. d. F. der ersten Änderungssatzung zur Prüfungs- und Studienordnung für den Master-Studiengang Architektur (M. Sc.) vom 21. September 2023
Im Zeitraum von März bis Juni 2023 wurde vom Lehrstuhl für Produktionswirtschaft der BTU Cottbus-Senftenberg die Studie mit dem Titel „Die Produktionssteuerung im digitalen Zeitalter“ als Online-Umfrage durchgeführt. 125 Personen mit operativen, planerischen und strategischen Funktionen in der Produktion oder des produktionsnahen Umfeldes beantworteten den Fragebogen. Die Studie zeigt, dass bei vielen Praktikern ein sehr klares Bild vorherrscht, was die Produktionssteuerung der Zukunft leisten muss. Die Erweiterung der Produktionssteuerung um Künstliche Intelligenz wird in sehr starkem Maße als sinnvoll erachtet, um die Effizienz am Shop-Floor bei hoher Komplexität der Leistungsprozesse auch in Zukunft aufrechtzuerhalten. Die ausgewerteten Daten zeigen, dass die aktuellen Systeme der Produktionssteuerung die Nutzer nicht in dem Ausmaß unterstützen, wie es erwartet wird. Die Nutzer sind gefordert, ihr Wissen und ihre Kompetenzen einzusetzen, um funktionale Defizite der Anwendungen zu kompensieren. Die Kooperation von Menschen und KI in der Produktionssteuerung wird als sinnvoll angesehen. Dabei wird eine Kombination aus menschlicher Arbeit und KI-Unterstützung bevorzugt, während eine vollautonome KI seltener favorisiert wird. Die Studienergebnisse zeigen eine wachsende Zustimmung und Offenheit für den Einsatz von KI als Werkzeug in der Produktionssteuerung, jedoch unter menschlicher Aufsicht und Beteiligung. Die Herausforderungen der Integration von Künstlicher Intelligenz in die Mensch-Maschine-Interaktion umfassen technische und soziale Aspekte. Um diesen Herausforderungen zu begegnen, sind geeignete Lösungsansätze notwendig, wie die Entwicklung sicherer Schnittstellen, robuste Datenschutzmaßnahmen aber auch Nutzerakzeptanzförderung durch Aufklärung und Schulung. Innerhalb eines hybriden Rahmens, wo der Mensch mit der KI arbeitet, müssen klare Regeln für die Interaktion definiert werden. Die KI soll die menschliche Entscheidungsfindung interaktiv unterstützen, neue Perspektiven bieten und alternative Vorschläge unterbreiten. Insgesamt betonen die Ergebnisse der Umfrage die Bedeutung von Sicherheit, Transparenz, Kontrolle und die Validierung von KI-Entscheidungen durch menschliche Akteure. Es zeigt sich, dass die Kombination von Menschen und KI nicht nur technologische Vorteile bietet, sondern auch dazu beitragen kann, nachhaltig wirtschaftlichere Ergebnisse zu erzielen.
During open-cast lignite mining in Lusatia (NE Germany), iron sulfide minerals associated with lignite, are exposed to air and weather. The weathering products iron (Fe), sulfate and acids subsequently enter the fluvial-lacustrine system Spree and its tributaries.
The aim of this work was to identify and explain the evolving biogeochemical signatures (spatio-temporal patterns) in River Spree. These signatures are significantly influenced by biogeochemical turnover processes triggered by iron input. To identify the signatures, a regional field study was conducted from the inland delta Spreewald to the mouth. This study was followed by two laboratory experiments under controlled redox conditions to investigate the effect of Fe on the long-term binding of phosphorus and the degradation of particulate organic material in the iron-enriched sediments.
Characteristic elements introduced by lignite mining (iron, sulfur, aluminum, cobalt, nickel) and by urban areas (zinc, lead, copper, chromium) could be determined by means of a principal component analysis. Based on these findings, the impact range of the open-cast mining was determined to be at least ~ 90 km downstream of the Spreewald. Within the urban-influenced systems Fürstenwalde and Berlin, the urban signature is more dominant than the mining signature. By means of sequential extractions and XRD analyses of the sediments, iron binding forms and characteristic iron minerals have been additionally identified (e.g., Fe(III) oxyhydroxides, pyrite, vivianite).
Sediment analyses and column experiments have shown that iron increases the phosphorus sorption and decreases the phosphorus release in the sediments of three studied lakes of the fluvial-lacustrine system. However, the application of different phosphorus retention models for Lake Neuendorfer See showed that Fe cannot reduce the eutrophic state of the lakes along the river, since the water retention times are too short and the external phosphorus loads are too high. Additionally, lake sediments with different Fe contents have been incubated with particulate organic material. Higher Fe contents resulted in reduced emissions of the greenhouse gases CO₂ and CH₄, which can be attributed to a reduced degradation of organic matter by Fe. Possible reasons include sorption processes of (dissolved) organic matter onto Fe oxyhydroxides and toxic effects of iron on microorganisms. Nevertheless, Fe (and sulfate) are available as electron acceptors during the decomposition of organic matter in River Spree.
The findings of this work deepen the understanding of the impact of iron from mining on sulfur, phosphorus and carbon turnover processes in fluvial-lacustrine systems. As a consequence of the Fe input from the Lusatian area, the signature will persist for decades in River Spree.
Im Zeitraum von Februar bis Mai 2023 wurde am Lehrstuhl für Produktionswirtschaft die Studie zum Thema „Technologische Trends und Entwicklungen alternativer Energiesysteme“ durchgeführt. Die vorliegende explorative Studie basiert auf leitfadengestützten Interviews von 54 Experten und Expertinnen aus Forschungsinstituten, der Wirtschaft sowie Branchenverbänden. Die Auswertung der Interviews folgte dem Prinzip der strukturierenden Inhaltsanalyse.
Für die allgemeine Entwicklung der erneuerbaren Energien und um zukunftsweisende Technologien zu identifizieren, ist es notwendig ein energiewirtschaftliches Zieldreieck mit den Ausprägungen Rentabilität, Versorgungssicherheit und Nachhaltigkeit in Einklang zu bringen. Die Fachkundigen zeigen auf, dass die politische Triebkraft maßgeblich darüber entscheidet, welche Technologien in Zukunft dominieren werden. Zukünftig wird es verstärkt zum Zusammenspiel einzelner Energiequellen in regional diversifizierten Konzepten, sowie zur Elektrifizierung und Sektorenkopplung kommen. Speichertechnologien werden verstärkt entwickelt und installiert werden. Prosuming und Demand-Side Response werden von den befragten Fachkundigen zukünftig als bedeutend erachtet.
In Bezug auf die einzelnen Energiequellen werden Wasserstofftechnologien zukünftig ein erhebliches Ausbaupotenzial aufweisen. Wasserstoff ermöglicht einen Beitrag zur Dekarbonisierung diverser Sektoren und dient darüber hinaus als Speichermedium fluktuierender Energien. Zusätzlich erfolgt eine Progression im Bereich von Wind- und Solarenergie. Dabei gewinnen im Bereich Photovoltaik, Technologien wie Agri- und Floating-PV an verstärkt an Bedeutung. Die Windkraftnutzung wird durch den Bau höherer Türme und die Vergrößerung von Rotorblattdimensionen optimiert. Geothermie spielt in Zukunft eine vielversprechende Rolle bei der Dekarbonisierung des Niedertemperatursektors. Das Ausbaupotenzial von Biomasse ist aufgrund von Flächenkonkurrenz begrenzt, obwohl sich, analog zu Wasserstoff, vielfältige Nutzungsmöglichkeiten eröffnen.
Im Bereich der Energiesysteme und -komponenten eröffnen sich diverse materialspezifische so wie fertigungstechnische Verbesserungspotenziale. Einige Technologien sind dabei bereits ausgereift, aber Optimierungsbedürftig. Technologien wie Elektrolyseure oder Wärmepumpen hingegen, bedürfen der grundlegenden Weiterentwicklung, um einen effizienten Betrieb zu ermöglichen. Im Bereich der Solarenergie liegen Entwicklungsschwerpunkte in der Verbesserung kombinierter Solar- und Photovoltaikmodule sowie von Trägerstrukturen für Agri-PV und langlebigeren Konzepten für die Schwimmkörper bei Floating PV vor. Schließlich zeigt sich auch hinsichtlich der Speichertechnologien ein Entwicklungsbedarf, insbesondere in Bezug auf Wasserstoffdruck- und -flüssigspeicher, Batteriespeicher und Latentwärmespeicher. Diese Fortschritte werden entscheidend sein, um eine nachhaltige und effiziente Energiewirtschaft der Zukunft zu gewährleisten.
1. Erste Änderungssatzung zur Prüfungs- und Studienordnung für den Master-Studiengang Klimagerechtes Bauen und Betreiben (M. Sc.) vom 11. September 2023
2. Lesefassung: Prüfungs- und Studienordnung für den Master-Studiengang Klimagerechtes Bauen und Betreiben (M. Sc.) vom 01. März 2018 i. d. F. der ersten Änderungssatzung zur Prüfungs- und Studienordnung für den Master-Studiengang Klimagerechtes Bauen und Betreiben (M. Sc.) vom 11. September 2023
In this work, a reliable kinetic reaction mechanism was revised to accurately reproduce the detailed reaction paths of steam reforming of methane over a Ni/Al2O3 catalyst. A steadystate fixed-bed reactor experiment and a 1D reactor catalyst model were utilized for this task. The distinctive feature of this experiment is the possibility to measure the axially resolved temperature profile of the catalyst bed, which makes the reaction kinetics inside the reactor visible. This allows for understanding the actual influence of the reaction kinetics on the system; while pure gas concentration measurements at the catalytic reactor outlet show near-equilibrium conditions, the inhere presented temperature profile shows that it is insufficient to base a reaction mechanism development on close equilibrium data. The new experimental data allow for achieving much higher quality in the modeling efforts. Additionally, by carefully controlling the available active surface via dilution in the experiment, it was possible to slow down the catalyst conversion rate, which helped during the adjustment of the reaction kinetics. To assess the accuracy of the revised mechanism, a monolith experiment from the literature was simulated. The results show that the fitted reaction mechanism was able to accurately predict the experimental outcomes for various inlet mass flows, temperatures, and steam-to-carbon ratios.
Diskriminierungsphänomene, ihre Formen, Spezifika und Auftretenshäufigkeiten sind für die Pflegeausbildung in Deutschland bisher noch nicht untersucht worden. Lehrkräfte in der Pflegeausbildung werden jedoch vermehrt mit Diskriminierungsereignissen konfrontiert, in denen Lernende Abwertung, Ausgrenzung und Benachteiligung erfahren. Lehrkräften in den gesundheitsbildenden Berufen obliegt der Auftrag, ein professionelles, ethisch fundiertes Pflegeverständnis bei Lernenden in der Pflegeausbildung zu entwickeln. Der Respekt vor der Würde des Menschen, die mit einem Diskriminierungsverbot einhergeht, ist dabei die zentrale ethische Prämisse bei der Ausübung des Pflegeberufes. Die Rolle von Lehrenden und ihre Haltung im Umgang mit diskriminierenden Praktiken von Lernenden sind bisher empirisch nicht untersucht worden. Die Zielstellung dieser empirisch qualitativen Studie mit Hilfe der Methodologie der (Reflexiven) Grounded Theory (nach Breuer et al., 2018; Strauss & Corbin, 1996) bestand daher: Die Erfahrungen von Lehrenden mit Diskriminierungsereignissen, ihre Umgangsweisen und die damit verbundenen Haltungen und Wissensbestände zu untersuchen. Die empirischen Daten wurden durch elf problemzentrierte Interviews (Witzel, 2000) erfasst und unter Verwendung des Kodierparadigmas (Strauss & Corbin, 1996) zu einem erklärenden Modell zusammengeführt. Im Mittelpunkt der Theorie stehen Diskriminierungsphänomene, die häufig als Rassismus, Antisemitismus, Klassismus, Lookismus, Linguizismus und als Gleich- und Ungleichbehandlung auftreten. Sie sind dabei teilweise intersektional verschränkt. Im Modell werden diese Diskriminierungsverhältnisse und ihre Ausdrucksformen über ein Kontinuum von kristalliner, latenter und amorpher Diskriminierung beschrieben. Abwertungs- und Ausgrenzungsprozesse sowohl durch Lernende als auch Lehrende finden in einem Kontext statt, die Merkmale einer Lehr- und Lernsituation darstellen: Sozialformen des Unterrichts, Themenwahl, Zusammensetzung der Lerngruppe und leitende Unterrichtsprinzipien. Diskriminierungsereignisse stehen daher mit dem Unterricht in einem relevanten Zusammenhang. Der situative Kontext ist als Bezugsrahmen zu verstehen, in denen Lehrende ihre Handlungsmöglichkeiten anwenden. In diesen Situationen wird der Umgang der Lehrenden mit Diskriminierungsprozessen von individuellen und strukturell-institutionellen Bedingungen beeinflusst, die Handlungsmöglichkeiten eröffnen oder blockieren. Die Bewältigungsmodi waren hierbei abhängig von: den Wissensbeständen der Lehrenden, von den institutionellen Faktoren, ihrer Grundhaltung zu den Lernenden und ihrem berufsbiografischen Wissen.
Recent advances in additive manufacturing offer promising opportunities for the fabrication of structures on existing micro-(opto-acoustic )electro-mechanical systems, i.e., chips. This is of particular significance in research and development due to the adaptability and adaptation speed of additive manufacturing. These advantages provide the ability to individualize the fabrication of structures and to enable the rapid prototyping approach. The combination of additive manufacturing on chip already enables current research, especially in photonic and microfluidic fields. Despite this, additive manufacturing on chip has never been applied to acoustic sensors or micro-positioning chips. Such devices could benefit from the mentioned advantages, especially for the fabrication of beam shaping waveguides, packaging, grating and end effector structures. Additive manufacturing by two-photon polymerization lithography gathers interest in industry and research due to its capabilities for the fabrication of structures with minimum feature sizes beyond the diffraction limit. The objective of this work is the investigation of additive manufacturing on chip by two-photon polymerization lithography at the example of an acoustic sensor and a micro-positioning chip. One of the greatest challenges is posed by the optical, thermodynamic, adhesion and alignment effects, which are introduced to the fabrication process by these complex substrates. Optical and thermodynamic models were established, and simulations were performed, culminating in a compensation method to address these effects, which was verified by parameter studies. The substrate alignment was investigated via optical technique, resulting in the development, manufacturing and verification of a novel alignment upgrade to the fabrication system employed in this work. The influence of process materials posed another challenge, as they led to chip performance alterations and restrictions. Chips treated with these materials were characterized, e.g., using high frequency optical microphones. Owing to the high precision of the alignment upgrade and the compensation method developed in this work, additive manufacturing on chip using two-photon polymerization lithography on the investigated devices was reported for the first time and presented for expedient examples, e.g., waveguides, end effectors and gratings. The residue contamination was determined as the main origin of the exhibited performance issues. Development strategies were recommended for further research, to enable additive manufacturing on chip insensitive to residual materials. In this work, the requirements for additive manufacturing on chip were illustrated and the fundamental arrangement to enable the rapid prototyping approach as well as design individualization were demonstrated. The compensation methods developed in this work facilitate upcoming research on desirable chip types that form the basis for optical and microfluidic applications.
With the large-scale expansion of decentralized power generation from renewable energy resources (RES) and reduction of fossil fuel-based power generation, this leads to fundamental structural changes in the power supply system. The transition is characterized by a shift from central to decentral, from directional to bi-directional. As the share of renewable power systems in the electricity grid increases, the inherent uncertainty of renewable energies poses challenges to the grid system’s stability.
To achieve increased efficiency, decarbonisation, decentralization, and digitisation in energy sector, a flexible and resilient energy system is required. Electrical energy data and non-electrical energy data are generated from various sources, including the supervisory control and data acquisition system (SCADA), geographic information system (GIS), and weather information system. Based on these data, different spatial and temporal models of energy systems and their databases are created and connected. This thesis contributes to the analysis of regional power performance. To this end, an efficient simplified grid-oriented network cluster is presented to account for the regional allocation of RES power systems. The model clustering includes the grid topology, temporal and spatial resolution, and the structure of electrical and non-electrical data. This approach contributes to methodological aspects of energy system modelling and analysis.
In addition, based on the proposed cluster model, this thesis presents the physical profile-based and data-driven methods to estimate the regional large-scale photovoltaic (PV) and wind power generations. In order to adapt to the spatial-temporal heterogeneity of the regional renewable power generations and to improve the local power utilization rate, this thesis conducts empirical analyses of the regional energy storage and combined PV and wind power systems using cable pooling with shared grid connection.
In summary, this thesis presents a flexible modelling approach that takes into account the regional allocation of renewable power systems and enables a more accurate estimation of regional power generation. The proposed model and analytical methods can help the efficiency and resiliency of the energy system and support the transition towards renewable energies.
Bored children begin to draw, do crafts, to fidget - or they do something bad. Others fall silent, withdraw, or become lethargic. Research on school-related boredom has focused primarily on the negative consequences of boredom, such as decreased cognitive performance, motivation or attentativeness, or disruptiveness. These negative aspects of boredom can be contrasted by the notion that boredom can promote creative performance. This paper reflects on boredom's creative and suppressive consequences as an interplay of personality traits and behavioral possibilities in school situations, on the one hand, and as an interplay of situational experiences with constituent developmental processes on the other. It is proposed that boredom is a gauge of the learner's resonance with school content, learning and/or developmental relationships. Boredom indicates a psychological need and its desideratum. Thus, both creative and suppressive potentials are inherent in boredom.
Result-based payments (RBPs) reward land users for conservation outcomes and are a promising alternative to standard payments, which are targeted at specific land use measures. A major barrier to the implementation of RBPs, particularly for the conservation of mobile species, is the substantial monitoring cost. Passive acoustic monitoring may offer promising opportunities for low-cost monitoring as an alternative to human observation. We develop a costing framework for comparing human observation and passive acoustic monitoring and apply it to a hypothetical RBP scheme for farmland bird conservation. We consider three different monitoring scenarios: daytime monitoring for the whinchat and the ortolan bunting, nighttime monitoring for the gray partridge and the common quail, and day-and-night monitoring for all four species. We also examine the effect of changes in relevant parameters (such as participating area, travel distance and required monitoring time) on the cost comparison. Our results show that passive acoustic monitoring is still more expensive than human observation for daytime monitoring. In contrast, passive acoustic monitoring has a cost advantage for nighttime as well as day-and-nighttime monitoring in all considered scenarios.
As the issue of pollutant emissions from aviation propulsion escalates, research into alternative powertrains is gaining momentum. Two promising technologies are the Hybrid Electric Propulsion System (HEPS) and Pressure Gain Combustion (PGC). HEPS is expected to reduce pollutant emissions by decreasing fuel consumption, whereas PGC uses detonation in the combustor to increase the thermal efficiency of engines by elevating the total pressure during combustion. This study extensively explores the integration of these two emerging technologies, thoroughly assessing the advantages that arise from their combination. First, the renowned turboprop engine PW127 is benchmarked and modeled using Gasturb software. The model is integrated into Simulink using the T-MATS tool, with HEPS and pressure gain components added to analyze the thermodynamics of various configurations under different pressure gain values and HEPS parameters. The analysis, conducted up to the cruise phase of the baseline aircraft, reveals that applying pressure gain combustion through Rotating Detonation Combustion (RDC) results in a more significant increase in efficiency and decrease in fuel consumption compared to HEPS with conventional gas turbines. However, HEPS helps maintain a more uniform combustor inlet condition and reduces the Turbine Inlet Temperature (TIT) at the takeoff phase, where the highest TIT otherwise occurs. The results suggest that integrating HEPS with PGC can be beneficial in maintaining optimal combustor conditions and mitigating turbine efficiency degradation.
The role of AJB35136 and fdtA genes in biofilm formation by avian pathogenic Escherichia coli
(2023)
Background Infections caused by avian pathogenic Escherichia coli (APEC) result in significant economic losses in poultry industry. APEC strains are known to form biofilms in various conditions allowing them to thrive even under harsh and nutrient-deficient conditions on different surfaces, and this ability enables them to evade chemical and biological eradication methods. Despite knowing the whole genome sequences of various APEC isolates, little has been reported regarding their biofilm-associated genes. A random transposon mutant library of the wild-type APEC IMT 5155 comprising 1,300 mutants was analyzed for biofilm formation under nutrient deprived conditions using Videoscan technology coupled with fluorescence microscopy. Seven transposon mutants were found to have reproducibly and significantly altered biofilm formation and their mutated genes were identified by arbitrary PCR and DNA sequencing. The intact genes were acquired from the wild-type strain, cloned in pACYC177 plasmid and transformed into the respective altered biofilm forming transposon mutants, and the biofilm formation was checked in comparison to the wild type and mutant strains under the same conditions.
Results In this study, we report seven genes i.e., nhaA, fdeC, yjhB, lysU, ecpR, AJB35136 and fdtA of APEC with significant contribution to biofilm formation. Reintroduction of AJB35136 and fdtA, reversed the altered phenotype proving that a significant role being played by these two O-antigen related genes in APEC biofilm formation. Presence of these seven genes across nonpathogenic E. coli and APEC genomes was also analyzed showing that they are more prevalent in the latter.
1. Erste Änderungssatzung zur Prüfungs- und Studienordnung für den Master-Studiengang Wirtschaftsingenieurwesen (M. Eng.) mit fachhochschulischem Studienprofil vom 24. August 2023
2. Lesefassung: Fachspezifische Prüfungs- und Studienordnung für den Master-Studiengang Wirtschaftsingenieurwesen (M. Eng.) mit fachhochschulischem Studienprofil vom 22. Oktober 2018 i. d .F. der Ersten Änderungssatzung zur Fachspezifischen Prüfungs- und Studienordnung für den Master-Studiengang Wirtschaftsingenieurwesen (M. Eng.) mit fachhochschulischem Studienprofil vom 24. August 2023
Anwendbare Materialgesetze im Rahmen der phänomenologischen Kontinuumsmechanik sind durch die berücksichtigten Deformationsmechanismen geprägt und sind in der Regel für einen anzugebenden Gültigkeitsbereich einsatzfähig. Die verwendeten mathematischen Werkzeuge geben einen ausreichenden Anpassungsspielraum experimenteller Daten, beziehen jedoch die Physikalität des Materialgesetzes bedingt ein, da der thermodynamische Prozess der Deformation als näherungsweise isotherm behandelt wird. In dieser Arbeit wird der Deformationsvorgang unter mechanischer Last als vollständiger thermodynamischer Prozess verstanden, der eine Temperaturentwicklung im Werkstoff einbezieht und die kalorischen Zustandsgrößen auswertet. Die Konzepte der Kontinuumsthermomechanik werden in der Beschreibung für thermodynamisch konsistente Materialgesetze genutzt. Die zugehörigen, mikrostrukturell motivierten Entwicklungsgrößen beschreiben das nichtlineare Verhalten für eine große Bandbreite von Materialklassen und in komplexen Belastungspfaden. Um dies für die Ermittlung geeigneter Materialgesetze nutzbar zu machen wird die Infrarotthermografie für die Ermittlung der Oberflächentemperatur in den Messablauf integriert. Hauptaugenmerk liegt auf dem technisch relevanten Anwendungsbereich der kleinen Deformationsgradienten bei Raumtemperatur. Anhand charakteristischer Belastungspfade für metallische Konstruktionswerkstoffe wird gezeigt, dass die Dynamik der Deformationsmechanismen sich in der Spannungs-Dehnungs-Charakteristik, in der Temperaturentwicklung und bei den kalorischen Zustandsgrößen signifikant widerspiegeln. Dies trifft insbesondere auch dann zu, wenn die Versuchsanforderungen minimiert werden und die gemessenen Temperaturänderungen klein sind. Die Ergebnisse der Arbeit weisen mit der Erweiterung des veränderlichen Temperaturfeldes einen Zugewinn in der Physikalität der thermodynamisch konsistenten Materialgesetze nach.
Das Internet der Dinge (IoT) und drahtlose Sensor-Netzwerke (WSNs) sind grundlegende Konzepte für die Vernetzung der heutigen globalen Informationsgesellschaft, die auf kleinen drahtlosen Geräten basiert. Wenn die Funktionalitäten oder Daten dieser Geräte manipuliert werden, kann der potenzielle Schaden erheblich sein. Daher ist die Sicherung der Datenübertragung zwischen diesen Geräten mithilfe von Kryptografie entscheidend. Die Sicherheit kryptografischer Algorithmen hängt jedoch von der Geheimhaltung der kryptografischen Schlüssel ab, die aufgrund der physischen Zugänglichkeit anfällig sein können. Side-Channel-Angriffe können diese Anfälligkeit ausnutzen, indem sie physikalische Parameter nutzen, die mit dem Betrieb kryptografischer Chips verbunden sind, wie z. B. die elektromagnetische Strahlung während kryptografischer Operationen.Als Antwort auf diese Herausforderung wurde in dieser Arbeit das "Leakage Source Cartography Tool" (LSC-Tool) entwickelt, um die Analyse der elektromagnetischen Strahlung in den elliptischen Kurvenkryptografie-Designs des IHP zu beschleunigen. Das LSC-Tool ermöglicht die automatisierte Auswertung von Sätzen von elektromagnetischen Traces, die aus verschiedenen Messpositionen über einen kryptografischen Chip gewonnen wurden. Die Analyse führt zu einer "Leakage Source Map" (LS-Map), die den Erfolg von elektromagnetischen Analyseangriffen an jeder Messposition darstellt. Dieses Tool bietet eine kostengünstige und schnelle Möglichkeit, die Widerstandsfähigkeit kryptografischer Designs gegen Angriffe zu bewerten, und bietet Designern Einblicke in die anfälligsten Bereiche des Chips sowie Informationen über den Leakage pro Taktzyklus.Durch den Einsatz des LSC-Tools wurde der Widerstand von zwei IHP ECC-Designs gegen horizontale differentielle elektromagnetische Analyseangriffe an 25 Messpositionen getestet. Die statistische Analyse von Traces kann mit drei Methoden durchgeführt werden: der Methode der kleinsten Quadrate, dem Difference-of-means-Test oder der Difference-of-the-mean-Methode. Die generierten LS-Maps zeigen, dass die Verwendung unterschiedlicher Methoden unterschiedliche Anzeichen für Leakagestellen liefert. Die Kombination dieser Karten erhöht die Erfolgsrate des Angriffs. Beachtenswert ist, dass im Laufe dieser Forschung klar wurde, dass das LSC-Tool angepasst werden kann, um LS-Maps für die funktionellen Blöcke von ECC-Designs zu erstellen und so die Analyse simulierter Power-Traces für das IHP ECC-Designs zu ermöglichen.
Die vorliegende Publikation präsentiert Ergebnisse von 55 Studierenden des Bachelorstudiengangs Städtebau und Stadtplanung aus dem Modul „Stadtmanagement 1, Vermittlung von Planung, Wohnungswirtschaft (SPB3)“, das im Wintersemester 2022/2023 am Fachgebiet Stadtmanagement der BTU Cottbus-Senftenberg stattgefunden hat.
Physiotherapy for patients with hip and knee osteoarthritis in Germany: a survey of current practice
(2023)
Osteoarthritis (OA) of the hip and the knee is common and leads to pain, stiffness and disability. Clinical practice guidelines (CPG) provide recommendations to assist healthcare professionals in clinical decision-making. Although evidence-based physiotherapy has been shown to be effective in the management OA, a gap between clinical practice and guideline recommendations exists. Little is known about OA management provided by physiotherapists in Germany and whether treatment aligns with CPGs. The objectives of this study were (1) to investigate the current physiotherapy practice in patients with hip and/or knee OA in Germany, (2) to evaluate physiotherapists’ adherence to guideline recommendations and (3) to explore barriers and facilitators to guideline use.
Titanium nitride (TiN) is a complementary metal-oxide-semiconductor (CMOS) compatible material with large potential for the fabrication of plasmonic structures suited for device integration. However, the comparatively large optical losses can be detrimental for application. This work reports a CMOS compatible TiN nanohole array (NHA) on top of a multilayer stack for potential use in integrated refractive index sensing with high sensitivities at wavelengths between 800 and 1500 nm. The stack, consisting of the TiN NHA on a silicon dioxide (SiO2) layer with Si as substrate (TiN NHA/SiO2/Si), is prepared using an industrial CMOS compatible process. The TiN NHA/SiO2/Si shows Fano resonances in reflectance spectra under oblique excitation, which are well reproduced by simulation using both finite difference time domain (FDTD) and rigorous coupled-wave analysis (RCWA) methods. The sensitivities derived from spectroscopic characterizations increase with the increasing incident angle and match well with the simulated sensitivities. Our systematic simulation-based investigation of the sensitivity of the TiN NHA/SiO2/Si stack under varied conditions reveals that very large sensitivities up to 2305 nm per refractive index unit (nm RIU−1) are predicted when the refractive index of superstrate is similar to that of the SiO2 layer. We analyze in detail how the interplay between plasmonic and photonic resonances such as surface plasmon polaritons (SPPs), localized surface plasmon resonances (LSPRs), Rayleigh Anomalies (RAs), and photonic microcavity modes (Fabry-Pérot resonances) contributes to this result. This work not only reveals the tunability of TiN nanostructures for plasmonic applications but also paves the way to explore efficient devices for sensing in broad conditions.
Aufbauend auf den Erkenntnissen wurden 15 Thesen herausgearbeitet, die potenzielle Impulse darstellen, um den sozialen Zusammenhalt anzuregen beziehungsweise zu stärken. Der soziale Zusammenhalt kann beispielsweise gestärkt werden, indem Cittaslow das Bewusstsein dafür schafft, das Thema immer wieder im politischen Alltag thematisiert wird und eine Grundhaltung bei allen beteiligten Akteur:innen dafür erzeugt wird. Zudem vermittelt Cittaslow gemeinsame Werte wie Integration, Identifikation und Entschleunigung, die den sozialen Zusammenhalt anregen können. Darüber hinaus kann Cittaslow mithilfe der grundlegenden Struktur den sozialen Zusammenhalt anregen: durch den Austausch im Netzwerk und der Präsenz von sozialem Zusammenhalt im Kriterienkatalog sowie in der Positionierung von Cittaslow und durch Aktionen in der Stadt. Zusammenfassend lässt sich sagen, dass Cittaslow als Impulsgeber:in agieren und sozialen Zusammenhalt anregen kann. Notwendig dafür ist jedoch ein starkes Engagement der Stadt sowie der jeweiligen Akteur:innen, insbesondere der Bürgermeister:innen.
Eisenhüttenstadt war als Planstadt ein Teil des politischen Projektes der DDR und unterlief mit den Wechseln in der Systemführung verschiedene Phasen der Begünstigung in der Stadtentwicklung. Im Zuge der Wiedervereinigung erfuhr die Stadtbevölkerung einen Verlust des zuvor gültigen Normen- und Wertesystems durch den Wegbruch des Eisenhüttenkombinats Ost (EKO) als Hauptarbeitgeber sowie als sozialer und kultureller Bezugspunkt. Seitdem ist die Stadtentwicklung von Abwanderungsprozessen geprägt, die in Teilen der Stadtbevölkerung maßgeblich zu der Entwicklung von ausgeprägten Ressentiments gegenüber den Werten und Normen der wiedervereinigten Bundesrepublik beigetragen haben. Ein in diesem Kontext angestoßener Leitbildentwicklungsprozess versucht Konflikt- und Innovationspotenziale der Stadtentwicklung zu erkennen und in Richtung einer langfristigen Zukunftsperspektive neu zu gestalten. Die Diskurse und Methoden dieser Leitbildentwicklung werden in dieser Arbeit anhand einer Narrationsanalyse untersucht. Ein besonderer Fokus wird dabei auf die Rolle der Jugendlichen als abwandernde Bevölkerungsschicht gelegt. Die Erstellung eines Leitbildes für die Stadt wird als Prozess verstanden, der darauf abzielt, neue Narrationen über die Stadtentwicklung in der Bevölkerung zu etablieren. Narrativisierungen verschiedener Deutungen über die Stadt werden dazu in die Prozessgestaltung der Leitbildfindung integriert. Anhand der ablehnenden Haltung der Stadtbevölkerung gegenüber dem Leitbild werden Prozessgestalt und Innovationskraft der Leitbildentwicklung kritisch hinterfragt sowie die Grenzen und Möglichkeiten von Leitbildentwicklungsprozessen aufgezeigt.
Christoph Dientzenhofer (1655–1722) is considered one of the most important Baroque master builders of Central Europe. From his extensive architectural oeuvre, a group of six church buildings with geometrically complex forms stands out, recognised by architectural historians as particularly innovative and influential. These churches, located in Bohemia (Czech Republic), and often collectively referred to as the ‘radical’, ‘dynamic’, ‘Guarinesque’, or simply ‘Bohemian’ group, are: St. Joseph in Obořiště (1702–11), the Castle Church in Smiřice (1702–11), St. Nicholas in the Lesser Town of Prague (1703–11), St. Clare in Cheb (1707–11), St. Margaret in Břevnov (1708–16), and the Church of the Holy Assumption in Nová Paka (1709–24). The brick vaults of these six buildings, sequences of oval domes and double-curved vault areas, are of particular interest for building research. In this study, the geometric design of the vaults of Dientzenhofer’s ‘radical’ churches is documented, analysed, and compared using 3D laser scans of the buildings as primary source. The 3D models generated from the scans enable a geometric analysis through the method of reverse geometric engineering, breaking down the vaults’ complex three-dimensional forms into their basic two-dimensional components: segments of circles with different radii and orientations, curved in one or two directions. These forms can be found in the architectural and stereotomic treatises that were widespread at the time. By comparing the vault geometry of the six churches with each other and with the geometric concepts discussed in the treatises, general statements can be made about the architect’s design choices. On the basis of this investigation, hypotheses are made about the design and underlying geometric ideas of the vaults of Dientzenhofer’s ‘radical group’, and the results are placed in context.
Der vorliegende Review Artikel thematisiert die Rückführung von abgelagerten Ressourcen aus Deponien und es werden verschiedene Deponieklassen in Anlehnung an die deutsche Deponieverordnung erläutert. Deutschland dient als positives Beispiel für die Errichtung sicherer Deponien, welche je nach Ablagerungsmaterial in unterschiedliche Deponieklassen unterteilt werden. Trotz der fortschrittlichen Ablagerung im internationalen Vergleich ist der Unterhalt einer solchen Deponie als nicht nachhaltig einzustufen. Die Rückgewinnung von Ressourcen ist eine Möglichkeit, die Nachhaltigkeit zu erhöhen. Allerdings ist es umständlich, Deponien zurückzubauen und den Abfall zu sortieren sowie aufzubereiten. Durch verschiedene Aufbereitungsverfahren kann zwischen unterschiedlichen Abfallarten differenziert und so der Output an die gegebene Situation angepasst werden. Unter den verschiedenen Wertstofffraktionen versprechen insbesondere Metalle einen großen Erlös beim Weiterverkauf. Bei Nichtmetallen steht die energetische Nutzung im Vordergrund. Neben den betraglichen Erlösen sind Opportunitätskosten von großer Bedeutung. Neben vermiedenen Kosten für die Instandhaltung werden auch sozialen und ökologischen Folgen reduziert. So können Landflächen zurückgewonnen werden, die als Baugrund genutzt werden können. Die effektive Verwertung von Abfall führt zu einer Reduktion, wodurch die ökologischen Folgen von zu viel Abfall eingegrenzt werden. Deponiebergbau findet schon in vielen Regionen der Welt seine Anwendung. In Anbetracht der Tatsache, dass die Ressourcenknappheit und der steigende Bedarf eine Einschränkung im Konsum hervorrufen können, wird die weitere Erforschung und die technische Umsetzung des Deponiebergbaus zunehmend wichtig.
1. Memristor-Symposium 2023
(2023)
The 1.Memristor-Symposium was held from 27-28.02.2023 in Bamberg. Young scientists and PhD students presented their research and covered several topics regarding ongoing memristive research in Germany. Several talks on the topic of memristive devices, their testing, modeling and usage were presented and discussed, covering the whole vertical integration from material and divice up to application level.
To increase our understanding of bacterial intestinal colonization in animal populations lacking anthropogenic influence we devised the first objective and studied the diversity of E. coli in pristine wild animal population. Overall, E. coli in cormorants maintained a high diversity under minimal anthropogenic influences. E. coli were isolated from individual birds of two cormorant colonies located on small islands in lakes at least 100 km away from human settlements. Diversity of the isolates was studied using pulsed field gel electrophoresis (PFGE). 137 isolates of cormorant colony-1 and 75 isolates of cormorant colony-2 resulted in 60 and 33 PFGE types, respectively. Representative strains of each PFGE type were analysed in terms of phylogroups, extraintestinal virulence associated genes (exVAGs), adhesion to the chicken intestinal cell line and antimicrobials. Most isolates belonged to phylogroup B1 (68.3%) followed by B2 and E with B2 harbouring the highest total number of exVAGs per isolate. Surprisingly, a PFGE type with relatively few exVAGs displayed the highest isolation frequency, also showing a high adhesion rate. Comparative analysis of exVAGs to other E. coli populations of wildlife origin revealed that the secreted autotransporter toxin encoding sat gene was only present in cormorants.
The second objective was to characterize and identify factors contributing to the novel adhesion phenotype, known as Clumpy adhesion by the strain 4972 E. coli when incubated on human urinary bladder 5637 cell line. Transcriptome and proteome of adhered bacteria clustered together and diverged from bacteria in the supernatant. The clumpy structure was further explored in terms antibiotic stress where sessile structures could tolerate high antibiotic pressure of ampicillin up to 16 mg/ml and gentamicin up to 2 µg/ml. Data analysis unveiled differential expression of 623 genes between bacteria forming clumps and in supernatant. 148 genes were hypothetical and five hypothetical genes i.e., ffp, espX1, pilV, spnT and yggT along with four known genes i.e., dnaK, spy, flgH and fimH were targeted for deletion. Seven genes deletion mutants, three known (i.e., spy, flgH and fimH) and four hypothetical (ffp, pilV, spnT and yggT) genes were successfully generated and analysed for various parameters. ΔflgH showed loss of clumpy phenotype and adhesion ability up to 80% was regenerated by complementation. When antibiotic stress by ampicillin was applied after clump formation, Δffp depicted no effect of high concentration of ampicillin. In case of ΔpilV, adhesion significantly increased to 151% and upon complementation, adhesion was reduced to 53%. ΔspnT during ampicillin stressed adhesion fared almost 8.5 times better than the wild type strain. ΔyggT exhibited high adhesion of 145.5 % and upon reintroduction, adhesion decreased to 13%. Overall, we were able characterize a new phenotype and determined the role of genes contributing to clumpy adhesion phenotype.