@misc{OPUS4-6496, title = {Amtliches Mitteilungsblatt der BTU Cottbus-Senftenberg, 2024,05 (24.04.2024)}, doi = {10.26127/BTUOpen-6496}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus4-64965}, year = {2024}, abstract = {Fachspezifische Pr{\"u}fungs- und Studienordnung f{\"u}r den Bachelor-Studiengang Angewandte Naturwissenschaften vom 23. April 2024}, language = {de} } @phdthesis{Hanschke2023, author = {Hanschke, Benjamin}, title = {Auswirkungen von Fremdk{\"o}rpersch{\"a}digungen und Blending Reparaturen auf die Aeroelastik von Hochdruckverdichter Blisks}, doi = {10.26127/BTUOpen-6687}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus4-66877}, school = {BTU Cottbus - Senftenberg}, year = {2023}, abstract = {Die vorliegende Arbeit befasst sich mit den Auswirkungen von Fremdk{\"o}rpersch{\"a}digungen und Blending Reparaturen auf das aeroelastische Systemverhalten einer modernen Hochdruckverdichter Blisk. Mittels einer vollautomatisierten Prozesskette zur Untersuchung parametrisch definierter Schadensf{\"a}lle erfolgt eine detaillierte Analyse der Korrelationsbeziehungen zwischen den Sch{\"a}digungsparametern und deren Einfluss auf die hochzyklische Erm{\"u}dungsfestigkeit der Komponente. Die hierbei gewonnenen Erkenntnisse fließen in ein Regressionsmodell zur Erstellung von Sensitivit{\"a}tsplots ein, um eine schnelle Beurteilung der Kritikalit{\"a}t von Schadensf{\"a}llen im Flottenbetrieb zu erm{\"o}glichen. Im Rahmen der aeroelastischen Analysen sind vor allem die Auswirkungen von Blending Reparaturen auf typische Kenngr{\"o}ßen wie die aerodynamische D{\"a}mpfung und Anregung von Interesse. Am Beispiel einer im Betrieb hoch ausgelasteten Schwingform wird eine potentielle {\"U}berlagerung mehrerer, f{\"u}r die Betriebssicherheit der Komponente kritischer, Effekte dargestellt. Um die Rechenzeiten f{\"u}r derartige Vorhersagen k{\"u}nftig zu verringern, werden zudem unterschiedliche Ans{\"a}tze zur Reduktion der Simulationsaufw{\"a}nde verglichen.}, subject = {Aeroelastik; Blending Repair; Fremdk{\"o}rpersch{\"a}digung; Foreign Object Damage; Blisk; Blisk; Aeroelastizit{\"a}t; Fremdk{\"o}rper; Sch{\"a}digung}, language = {de} } @misc{Chatziandreou2024, type = {Master Thesis}, author = {Chatziandreou, Konstantinos}, title = {Climate governance in World Heritage cities}, doi = {10.26127/BTUOpen-6686}, url = {http://nbn-resolving.de/urn:nbn:de:kobv:co1-opus4-66869}, school = {BTU Cottbus - Senftenberg}, year = {2024}, abstract = {This study explores the interplay between the UNESCO status and climate governance in World Heritage cities. With climate change posing significant threats to living urban landscapes, local governments and public actors strive to implement sustainable and resilient strategies. However, complications arise when cities attain the World Heritage status, complicating climate governance practices. Qualitative research, involving interviews with key stakeholders from the Climate and Monument Protection Departments in L{\"u}beck, Regensburg, and Bamberg, reveals a negative impact of cultural heritage on climate governance. The study contends that, when harnessed effectively, cultural heritage can contribute to the sustainability and resilience of cities in addressing climate change. It emphasises the necessity for flexibility, collaboration, and a human-centric approach, advocating for a common understanding and prioritisation of human life within climate governance. In conclusion, this research underscores the importance of viewing heritage as a dynamic component integrated into cities' climate governance strategies.}, subject = {Climate change; Climate governance; Cultural heritage; UNESCO; World Heritage cities; Klimawandel; Klimagovernance; Kulturerbe; Welterbest{\"a}dte; Welterbe; Kulturerbe; Klimawandel; Klima{\"a}nderung; Stadtlandschaft; Governance}, language = {en} } @book{Kuennemann2022, author = {K{\"u}nnemann, Andreas}, title = {Existenz- und Regularit{\"a}tstheorie der zweidimensionalen Variationsrechnung mit Anwendungen auf das Plateausche Problem f{\"u}r Fl{\"a}chen vorgeschriebener mittlerer Kr{\"u}mmung}, publisher = {Springer}, address = {Heidelberg}, isbn = {978-3-658-41640-9}, doi = {10.1007/978-3-658-41641-6}, publisher = {BTU Cottbus - Senftenberg}, pages = {247}, year = {2022}, abstract = {Die vorliegende Arbeit behandelt f{\"u}r eine breite Klasse zweidimensionaler Variationsprobleme eine Existenz- und Regularit{\"a}tstheorie, die der L{\"o}sung von Randwertproblemen partieller Differentialgleichungssysteme dient. Dabei werden bekannte Ergebnisse gr{\"u}ndlich untersucht und umfassend aufgearbeitet. Teilweise wird eine geeignete Anpassung der Voraussetzungen einiger Resultate vorgenommen. Speziell wird die Theorie auf das Plateausche Problem f{\"u}r Fl{\"a}chen vorgeschriebener mittlerer Kr{\"u}mmung im R3 angewendet. Eingangs wird das Konzept der direkten Methoden der Variationsrechnung erl{\"a}utert. {\"U}ber einen fundamentalen Satz zur schwachen Unterhalbstetigkeit von Funktionalen wird die Existenz eines Minimierers f{\"u}r eine breite Klasse von Variationsproblemen nachgewiesen. Da die Existenztheorie in Sobolev-R{\"a}umen agiert, sind Untersuchungen zur Regularit{\"a}t eines Minimierers notwendig. Im Rahmen der Regularit{\"a}tstheorie wird das Dirichletsche Wachstumstheorem von Morrey gezeigt, welches ein hinreichendes Kriterium f{\"u}r die H{\"o}lder-Stetigkeit einer Funktion X ∈ W1,2(G) liefert. Zum Nachweis der Anwendbarkeit des Dirichletschen Wachstumstheorems auf einen Minimierer wird ein Wachstumslemma verwendet. Dabei werden eine Verkn{\"u}pfung des Dirichlet-Integrals mit Fourierreihen sowie das Dirichlet- Integral der harmonischen Ersetzung einer Funktion mit L2-Randwerten genutzt. Infolgedessen ergibt sich die H{\"o}lder-Stetigkeit im Inneren f{\"u}r einen Minimierer. Zudem wird die Stetigkeit des Minimierers bis zum Rand gezeigt, sodass die Existenz eines stetigen Minimierers f{\"u}r eine breite Klasse von Variationsproblemen gesichert ist. Anschließend erfolgt die Berechnung der ersten Variation sowie die damit verbundene Herleitung der schwachen Euler-Lagrange-Gleichung, welche eine Beziehung zur L{\"o}sungstheorie von Differentialgleichungen im Sinne des Dirichletschen Prinzips herstellt. Ausgehend von der schwachen Euler-Lagrange-Gleichung wird die H{\"o}lder-Stetigkeit der ersten Ableitungen eines Minimierers bewiesen. F{\"u}r die L{\"o}sung von Randwertproblemen mit partiellen Differentialgleichungen zweiter Ordnung mithilfe der Variationsrechnung ist der Nachweis stetiger zweiter Ableitungen des Minimierers notwendig. Dabei wird der Fokus auf sogenannte Minimierer vom Poissonschen Typ gelegt. Eine C2,σ-Rekonstruktion, die auf der Schaudertheorie basiert, liefert in diesem Fall die gew{\"u}nschte Regularit{\"a}t. In Anwendung dessen werden das Randwertproblem harmonischer Abbildungen in Riemannschen R{\"a}umen sowie das Dirichletproblem des H-Fl{\"a}chen-Systems behandelt, indem jeweils ein geeignetes Variationsproblem aufgestellt wird. Als Erweiterung des Dirichletproblems des H-Fl{\"a}chen-Systems wird das allgemeine Plateausche Problem f{\"u}r Fl{\"a}chen vorgeschriebener mittlerer Kr{\"u}mmung mit den erarbeiteten Methoden der Variationsrechnung untersucht. Zudem wird das Plateausche Problem f{\"u}r Fl{\"a}chen vorgeschriebener mittlerer Kr{\"u}mmung in Kugeln, in Zylindern sowie insbesondere im Einheitskegel gel{\"o}st. Insgesamt wird eine ausf{\"u}hrliche, in sich geschlossene und gut verst{\"a}ndliche Existenzund Regularit{\"a}tstheorie der zweidimensionalen Variationsrechnung zur Behandlung von Randwertproblemen partieller Differentialgleichungssysteme dargestellt, welche sich in besonderer Weise bei der L{\"o}sung des Plateauschen Problems f{\"u}r Fl{\"a}chen vorgeschriebener mittlerer Kr{\"u}mmung entfaltet.}, subject = {Variationsrechnung; Variationsrechnung; Dimension 2; Mittlere Kr{\"u}mmung; Plateau-Problem; Partielle Differentialgleichungen; Plateausches Problem; Regularit{\"a}tstheorie; Morrey; Variation calculation; Partial differential equations; Plateau problem; Regularity theory}, language = {de} } @article{BoellmannMartienssen2024, author = {B{\"o}llmann, J{\"o}rg and Martienssen, Marion}, title = {Seasonal variability of cultivable nitrate-reducing and denitrifying bacteria and functional gene copy number in fresh water lake}, series = {microorganisms}, volume = {12}, journal = {microorganisms}, number = {3}, publisher = {MDPI}, address = {Basel}, issn = {2076-2607}, doi = {10.3390/microorganisms12030511}, year = {2024}, abstract = {This study describes the seasonal course of denitrifying and nitrate-reducing bacteria in a dimictic mesotrophic lake (Lake Scharm{\"u}tzelsee, Brandenburg, Germany) within a three-year period from 2011 to 2013. The bacterial cell numbers were quantified by the fluorescence microscopy, most probable number (MPN) and PCR-dependent quantification of the chromosomal 16S rDNA and of the nirS and nirK gene copy number. The highest seasonal differences (up to three orders of magnitudes) have been measured usingMPNin the epilimnion. This variation was not reflected by PCR-dependent approaches or direct microscopical enumeration. At adverse conditions (low temperature and/or low nitrate concentrations), the differences between MPN and gene copy numbers increased by up to five orders of magnitudes and decreased to one magnitude at favourable environmental conditions. These results can be explained best by an increasing ratio of viable but not cultivable (VBNC) cells or dead cells at impairing conditions. In the hypolimnion, the courses of MPN and nir gene copy numbers were similar. This can be explained by a higher feeding pressure and therefore smaller amounts of dormant cells. In the pelagial in general, the total cell numbers enumerated by either microscopical or molecular approaches were similar. In the sediment, more than 99\% of the DNA was obviously not related to viable bacteria but was rather DNA in dead cells or adsorbed to particle surfaces.}, subject = {Denitrification; Nitrite reductase; Microscopical cell number; Hypolimnion; Dimictic lake; Denitrifikation; Nitrit-Reduktase; Mikroskopische Zellzahl; Dimiktischer See}, language = {en} } @book{Ceritoglu2023, author = {Ceritoglu, Erdogan Onur}, title = {Salvaging Buildings : reclaiming a livelihood from the excesses of Istanbul's mass urbanization}, publisher = {transcript}, address = {Bielefeld}, publisher = {BTU Cottbus - Senftenberg}, pages = {268}, year = {2023}, abstract = {Turkey's demolition waste management is, to a great extent, dependent on {\c{c}}{\i}kmac{\i}s (reclaimers) who salvage condemned buildings for raw materials and architectural elements. Its urbanization history is full of key moments marked by building demolitions, which became a necessary material resource for informal urbanization. As early as the 1970s, the {\c{c}}{\i}kmac{\i}s helped the gecekondus [squatter houses] by supplying second-hand building materials and construction loans. They managed to turn a lack of infrastructure into an advantage and remain very adaptable to the ever-changing conditions of neo-liberalized urbanization. They depend on solidarity networks and other informal resources. Assemblage thinking helps to redefine the concept of informality, understand the relational dynamics between various actors, and focus on the agency of materials. The empirical data gained from 'follow the thing' ethnographic research in Turkey and Georgia reveals the double lives of {\c{c}}{\i}kmac{\i}s who move between village and city. Additionally, by following the example of a reclaimed window frame's journey from Istanbul to Tbilisi, we can more clearly see the second-hand trade network in the context of urbanization and incremental architecture. In the context of waste's materiality, the empirical part of the research shows the symbiotic relationship between {\c{c}}{\i}kmac{\i}s and the discarded demolition materials.}, subject = {Architecture; Urbanisation; Building salvage; Informality; Turkey; Architektur; Urbanisierung; Bergung von Geb{\"a}uden; Informalit{\"a}t; T{\"u}rkei; Istanbul; Verst{\"a}dterung; Stadtentwicklung; Geb{\"a}ude; Abbruch; Bauabfall; Recycling}, language = {en} } @article{ZschechLechowskiKuturkovaetal.2024, author = {Zschech, Ehrenfried and Lechowski, Bartlomiej and Kuturkova, Kristina and Panchenko, Luliana and Kr{\"u}ger, Peter and Clausner, Andr{\´e}}, title = {Laboratory X-ray microscopy of 3D nanostructures in the hard X-ray regime enabled by a combination of multilayer X-ray optics}, series = {Nanomaterials}, volume = {14}, journal = {Nanomaterials}, number = {2}, publisher = {MDPI}, address = {Basel}, issn = {2079-4991}, doi = {10.3390/nano14020233}, year = {2024}, abstract = {High-resolution imaging of buried metal interconnect structures in advanced microelectronic products with full-field X-ray microscopy is demonstrated in the hard X-ray regime, i.e., at photon energies > 10 keV. The combination of two multilayer optics—a side-by-side Montel (or nested Kirkpatrick-Baez) condenser optic and a high aspect-ratio multilayer Laue lens—results in an asymmetric optical path in the transmission X-ray microscope. This optics arrangement allows the imaging of 3D nanostructures in opaque objects at a photon energy of 24.2 keV (In-Kα X-ray line). Using a Siemens star test pattern with a minimal feature size of 150 nm, it was proven that features < 150 nm can be resolved. In-Kα radiation is generated from a Ga-In alloy target using a laboratory X-ray source that employs the liquid-metal-jet technology. Since the penetration depth of X-rays into the samples is significantly larger compared to 8 keV photons used in state-of-the-art laboratory X-ray microscopes (Cu-Kα radiation), 3D-nanopattered materials and structures can be imaged nondestructively in mm to cm thick samples. This means that destructive de-processing, thinning or cross-sectioning of the samples are not needed for the visualization of interconnect structures in microelectronic products manufactured using advanced packaging technologies. The application of laboratory transmission X-ray microscopy in the hard X-ray regime is demonstrated for Cu/Cu6Sn5/Cu microbump interconnects fabricated using solid-liquid interdiffusion (SLID) bonding.}, subject = {X-ray microscopy; High-resolution radiography; Nanostructure; Advanced packaging; R{\"o}ntgenmikroskopie; Hochaufl{\"o}sende Radiographie; Nanostruktur; Erweiterte Verpackung; Nanostruktur; R{\"o}ntgenmikroskopie; Radiographie}, language = {en} } @article{RosenGribat2023, author = {Rosen, Christian and Gribat, Nina}, title = {Comparing hybrid urbanisms in the global south : water delivery configurations in Peru and Ghana}, series = {Urban Planning}, volume = {8}, journal = {Urban Planning}, number = {4}, publisher = {Cogitation}, address = {Lissabon}, issn = {2183-7635}, doi = {10.17645/up.v8i4.7155}, pages = {340 -- 350}, year = {2023}, abstract = {Urban development processes in the Global South (and North) are often described as characterized by formal and informal practices of different actors and their respective material realities. In critical urban studies, the disposition for this binary conception of formal and informal urbanisms has been discussed for many years. To a certain extent, these sometimes align rather problematically with contrasting notions of the "structural" versus the "everyday." In this article, we explore an understanding of formal and informal urban practices (and respectively "structure" and "everyday") as always interrelated, and we develop a methodology for a comparative examination of such hybrid urbanisms. In doing so, we address a missing link in the surging theoretical debate on comparative/southern urbanisms, which has rarely been substantiated by methodological explorations. The adapted concept of "delivery configurations" combines analyses of actor networks, material realities, rules and regulations, discourses, and heterogenous arrays of urban practices of negotiating these. However, bringing together local particularities and structural commonalities and exploring their interrelation only provides a basis for understanding case-specific complexities. We argue that embedding the analysis in a multi-scalar comparative framework can further its analytical rather than descriptive attributes and provide deeper insights into issues such as social inequality. To illustrate our methodological contribution, we provide first insights from a comparative research project of water delivery in different neighbourhoods in the secondary cities of Sunyani (Ghana) and Arequipa (Peru). We highlight the practical challenges of comparing diverse urban contexts and examining the rather complex relationships between infrastructure delivery, urban development, and social inequality.}, subject = {Water; Hybridity; Infrastructures; Multi-scalar comparison; Peru; Ghana; Wasser; Infrastruktur; Multiskalarer Vergleich; Infrastruktureinrichtungen}, language = {en} } @article{LeunerHirschl2023, author = {Leuner, Bruna and Hirschl, Bernd}, title = {Biomass and bioenergy perspectives of a coal region : status quo, potential and scenarios in Lusatia}, series = {Frontiers in Energy Research}, volume = {11}, journal = {Frontiers in Energy Research}, number = {1275733}, publisher = {Frontiers}, address = {Lausanne}, issn = {2296-598X}, doi = {10.3389/fenrg.2023.1275733}, year = {2023}, abstract = {Coal has been one of the main fuels used in Europe. Its decreasing role due to the ongoing transformation of the energy system will create significant socio-economic challenges. The switch into renewable energy systems could be an alternative to maintain jobs and economic activities within the affected regions. Biomass use and bioenergy can play an important role in the energy transition. Instead of energy crops, forest and agricultural residues should be used as biogenic energy sources in the future to avoid impacts on land use and food security. The main objective of this article is to investigate the biomass potential of a coal region and to provide scenarios for the future development of bioenergy production. Due to the changing framework conditions and, as a result, the different biomass focuses, previous bioenergy potential estimates must be reviewed. The methods for determining the potential of biomass for energy production was used for Lusatia (in German: Lausitz), the second largest coal region in Germany. These methods can also be applied in other regions. As a first step, the regional status quo assessment of cultivated areas and yields had decisive relevance for calculating biomass potential ranges. In a second step, the current bioenergy facilities in the region were identified, with a focus on power and heat production. The third step was the estimation of future regional bioenergy use. Therefore, the regional potential was gathered with the generally supra-regional framework conditions. For this purpose, national scenario studies were used, which contain the relevant target values and framework conditions. Two scenarios were developed for future bioenergy estimations: a conservative path based on the current policies and a progressive path, derived from the goal of climate neutrality by 2045. The results show a qualitative comparison among both scenarios and the previously determined potential ranges. Bioenergy can probably contribute to achieving climate neutrality with an increase in wood-fired systems, while agricultural bioenergy potential is likely to decline. In the discussion section, however, the uncertainty of these results is pointed out, as future use of bioenergy will be heavily influenced by the regulatory framework, competition with material use and the influences of climate change.}, subject = {Regional biomass potential; Bioenergy scenarios; Coal region; Regional energy transition; Lusatia; Regionales Biomassepotenzial; Bioenergieszenarien; Kohleregion; Regionale Energiewende; Lausitz}, language = {en} } @article{TomasMarinRodriguezCalcerradaArenasCastroetal.2023, author = {Tom{\´a}s Mar{\´i}n, Sergio de and Rodr{\´i}guez-Calcerrada, J{\´e}sus and Arenas-Castro, Salvador and Prieto, Iv{\´a}n and Gonz{\´a}lez, Guillermo and Gil, Luis and Riva, Enrique G. de la}, title = {Fagus sylvatica and Quercus pyrenaica : two neighbors with few things in common}, series = {Forest Ecosystems}, volume = {10}, journal = {Forest Ecosystems}, publisher = {Beijing Foresty University}, address = {Beijing}, issn = {2197-5620}, doi = {10.1016/j.fecs.2023.100097}, year = {2023}, abstract = {The Iberian Peninsula comprises one of the largest boundaries between Mediterranean and Eurosiberian vegetation, known as sub-Mediterranean zone. This ecotone hosts many unique plant species and communities and constitutes the low-latitude (warm) margin of numerous central European species which co-occur with Mediterranean vegetation. Two of the main species found in this region are the Eurosiberian European beech (Fagus sylvatica L.) and the Mediterranean Pyrenean oak (Quercus pyrenaica Willd.). It remains unclear how the different physiological and adaptive strategies of these two species reflect their niche partitioning within a sub-Mediterranean community and to what extent phenotypic variation (intraspecific variability) is driving niche partitioning across Eurosiberian and Mediterranean species. We quantified functional niche partitioning, based on the n-dimensional hypervolume to nine traits related to resource acquisition strategies (leaf, stem and root) plus relative growth rate as an additional whole-plant trait, and the environmental niche similarity between Pyrenean oak and European beech. Further, we analyzed the degree of phenotypic variation of both target species and its relationship with relative growth rates (RGR) and environmental conditions. Plant recruitment was measured for both target species as a proxy for the average fitness. Species' functional space was highly segregated (13.09\% overlap), mainly due to differences in niche breadth (59.7\%) rather than niche replacement (25.6\%), and beech showed higher trait variability, i.e., had larger functional space. However, both species shared the environmental space, i.e., environmental niches were overlapped. Most plant traits were not related to abiotic variables or RGR, neither did RGR to plant traits. Both target species share similar environmental space, however, show notably different functional resource-use strategies, promoting a high complementarity that contributes to maintaining a high functionality in sub-Mediterranean ecosystems. Therefore, we propose that conservation efforts be oriented to preserve both species in these habitats to maximize ecosystem functionality and resilience.}, subject = {Environmental niche; European beech; Forest dynamics; Functional niche; Pyrenean oak; {\"O}kologische Nische; Europ{\"a}ische Buche; Walddynamik; Funktionelle Nische; Pyren{\"a}en-Eiche; Iberische Halbinsel; {\"O}koton; {\"O}kologische Nische; Rotbuche; Pyren{\"a}eneiche; Artenschutz; {\"O}kosystem}, language = {en} }