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Most plastic products in circulation worldwide are based on fossil petroleum and are not biodegradable,which is known to be one of the biggest burdens and threats to the environment. One possible solution to this problem could be the use of bio-based and biodegradable polyhydroxybutyrate (PHB). Undernitrogen and phosphate depletion, Synechocystis sp. PCC 6714 produces PHB. As a positive side-effect,this method also binds the greenhouse gas CO2 through photosynthesis.This thesis analyses the results of a series of experiments carried out as part of basic research to better understand a possible PHB production process. The main goal was to investigate the effects of different lactose concentrations between 1 and 10 g/L from concentrated whey on the microorganism,particularly on the PHB production. The following three main results were obtained:Firstly, the cyanobacterium strain used could not metabolise lactose and even showed lower growth andPHB content of 2.2% at 1 g/L lactose compared to 4.2% without the addition of whey in the shake flaskexperiment. When upscaling in a photobioreactor, the same ratios were observed between cultivationswith and without whey, with the PHB content doubling to 6.5 and 10.5% (volumetric productivity 7.7and 21.1 mg/L/day).Secondly, the standard hydrolysation method for PHB quantification with concentrated sulfuric acid was compared with the alkaline sodium hydroxide method using a multivariate data analysis.Subsequently, the more promising acidic method was further optimised to reduce viscosity of sulfuricacid, gaining an optimum at 160 min, 14 M H2SO4, 100°C.Thirdly, as an alternative to the state of the art methods for recovering PHB, which use, e.g. the harmful chloroform, three ionic liquids based on the cation 1-Ethyl-3-methylimidazolium with three differentanions Dimethylphosphate, Acetate or Chloride were tested to dissolve the biomass but not thebiopolymer. 1-Ethyl-3-methylimidazolium Dimethylphosphate completely dissolved the biomass at75°C after 1 h and did not decompose or dissolve the PHB so that it could be implemented in a complete recovery process.

Das Ziel dieser Arbeit besteht in der Entwicklung von Modellierungsstrategien mittels fortgeschrittener Methoden im Rahmen der Finiten Elemente Methode, die es erm��glichen, das Ein- und Durchschlagverhalten von gewebeverst��rkten laminierten Verbundwerkstoffen vorherzusagen. Dabei soll neben der gesamten Energieabsorption des Laminats auch deren Aufteilung auf einzelne Mechanismen vorhergesagt werden, wobei Faserbruch, Zwischenfaserbruch, Delamination und die Akkumulation inelastischer Verzerrungen betrachtet werden. Innerhalb der vorliegenden Arbeit werden haupts��chlich Hochenergie-Einschl��ge im mittleren Geschwindigkeitsbereich betrachtet. Folglich werden ein dynamisches Einschlagverhalten und eine Durchdringung des Laminats erwartet. Es werden Modellierungsstrategien auf unterschiedlichen L��ngenskalen entwickelt um, zum einen, einen detaillierten Einblick in das Ein- und Durchschlagverhalten von gewebeverst��rkten Laminaten zu gewinnen und, zum anderen, das Einschlagverhalten von ganzen Bauteilen aus Verbundwerkstoffen zu simulieren. Es wird eine auf Schalenelementen basierende Modellierungsstrategie entwickelt, welche die Gewebetopologie auf der Ebene einzelner Faserb��ndel aufl��st. Diese erweist sich als effizient genug, um Simulationen des hoch dynamischen, nichtlinearen Verhaltens von gewebeverst��rkten Probenk��rpern unter Einschlagbelastungen im Rahmen eines vern��nftigen Rechenaufwands durchzuf��hren. Der Modellierungsansatz wird basierend auf experimentellen Fallgewicht-Einschlagtests auf Kohlefaser/Epoxy Laminaten, welche bei Kooperationspartnern durchgef��hrt werden, verifiziert. Es wird eine sehr gute ��bereinstimmung zwischen den Simulationsergebnissen und den experimentellen Daten festgestellt. Dar��berhinaus geben die Vorhersagen einen detaillierten Einblick in das Ein- und Durchschlagverhalten von gewebeverst��rkten Verbundwerkstoffen. Au��erdem wird eine auf Ebene der Laminat-Einzellagen basierende Strategie zur Modellierung und Simulation des Ein- und Durchschlagverhaltens von gewebeverst��rkten Laminaten bis hin zur kompletten Durchl��cherung entwickelt. Besonderes Augenmerk wird auf die numerische Effizienz gerichtet, um die M��glichkeit der Simulation von Einschlagvorg��ngen auf strukturelle Bauteile innerhalb vern��nftigen Rechenaufwands zu er��ffnen. Der Modellierungsansatz wird basierend auf experimentellen Fallgewicht-Einschlagtests auf Kohlefaser/Epoxy Laminaten, welche bei Kooperationspartnern durchgef��hrt werden, verifiziert. Das vorhergesagte Sch��digungs- und Versagensverhalten ist in sehr enger ��bereinstimmung mit den experimentellen Beobachtungen. Dar��berhinaus erweist sich dieser Modellierungsansatz als numerisch ��u��erst effizient. Ein ausf��hrlicher Vergleich des Energieabsorptionsverhaltens zwischen dem Einzellagen- und dem Faserb��ndel-Modellierungsansatz wird durchgef��hrt um den Einfluss unterschiedlicher Modellierungs-L��ngenskalen zu beurteilen. Schlie��lich wird ein Modellierungsansatz zur Simulation des Ein- und Durchschlagverhaltens von gro��en laminierten Verbundwerkstoff-Bauteilen innerhalb einer vern��nftigen Rechenzeit vorgestellt. Ein weiterer Schwerpunkt liegt auf der Simulation von Hochenergie-Einschl��gen auf glasfasergewebeverst��rkten Epoxy Laminaten bis hin zur kompletten Durchl��cherung. Dabei wird der entwickelte Einzellagen-Modellierungsansatz mit einem Einbettungsansatz kombiniert. In einem ersten Schritt wird die Anwendbarkeit des Einzellagen-Ansatzes zur Simulation von Hochenergie-Einschl��gen auf Glasfaser/Epoxy Laminate basierend auf Vergleichen mit experimentellen Fallgewicht-Einschlagtests, welche bei Kooperationspartnern durchgef��hrt werden, ��berpr��ft. Darauffolgend werden, als Beispiel einer Anwendung, zwei Konfigurationen eines generischen fan containment casing eines Flugzeug-Triebwerks untersucht, welche einem fan blade out Lastfall unterzogen werden. Dabei wird eine tiefe Einsicht in das Bauteilverhalten w��hrend des fan blade out gewonnen. The aim of the present work is to develop modelling strategies by means of advanced methods within the framework of the Finite Element Method (FEM), which are capable of predicting the impact behaviour of fabric reinforced laminated composites. Not only the total energy absorption of the laminate, but also the share of energy absorbed by individual mechanisms is predicted, where fibre rupture, matrix cracking, delamination and the accumulation of inelastic strains are considered. Within the present work, mainly high energy impact scenarios with intermediate impact velocities are considered. Hence, a dynamic impact response and penetration of the laminate are expected. Modelling strategies at different geometrical length scales are developed which on the one hand, aim at gaining a detailed insight into the impact behaviour of fabric reinforced laminates and on the other hand, aim at simulating the impact behaviour of entire composite components. A shell element based modelling strategy, which resolves the fabric topology at the level of individual tows (i.e.~impregnated bundles of fibres) is developed. It proves to be efficient enough to conduct simulations of the highly dynamic, nonlinear behaviour of fabric reinforced composite coupon specimens under impact loading within reasonable computational resources. The modelling approach is verified based on experimental drop weight impact tests of carbon/epoxy laminates carried out by cooperation partners. Very good agreement between the simulation results and the experimental data is found. Furthermore, the predictions give detailed insight into the impact behaviour of fabric reinforced composites. Also, a ply-level based strategy for modelling and simulating the impact behaviour of fabric reinforced laminates up to complete perforation is developed. Special attention is directed towards numerical efficiency in order to open up the possibility for simulating impact on structural components much larger than coupon specimens within reasonable computation time. The modelling approach is verified based on experimental drop weight impact tests of carbon/epoxy laminates carried out by cooperation partners. The predicted damage and failure behaviour is in very close agreement with the experimental observations. Furthermore, the approach is found to be of exceptional numerical efficiency. A detailed comparison of the predicted energy absorption behaviour between the ply-level and the tow-level modelling approach is conducted in order to evaluate the effect of different modelling length scales. Finally, a modelling approach for simulating the impact behaviour of large laminated composite components impacted by large deformable bodies within reasonable computation time and resources is presented. Another focus is set on the simulation of high energy impact on glass fabric reinforced epoxy laminates up to complete perforation. Thereby, the developed ply-level modelling approach is used in combination with an embedding approach. In a first step, the applicability of the ply-level approach to the simulation of high energy impact on glass/epoxy laminates is verified based on a comparison with experimental drop weight impact tests carried out by cooperation partners. Then, to demonstrate an application, two configurations of a generic composite fan containment casing of a jet engine subjected to fan blade out are investigated, where detailed insight into the components' behaviour during the fan blade out event is gained.

This Master’s thesis examines the carbon dioxide emissions of coal-fired steam operations on Austrian heritage and touristic railways, discusses problems in procurement, storage, and quality of coal, and gives an overview of the status of experience, current operation, and plans of alternative firing methods. The shift away from coal as an energy source due to climate change mitigation efforts and the global energy crisis are making bituminous coal more difficult to procure. This results in poor quality and high prices, putting pressure on steam operators, and creating challenges for the future. Two possible alternative firing methods to provide similar performance discussed in this thesis are oil firing and the use of biomass-based coal substitutions with similar energy density. While conversion to oil firing involves a high financial outlay and does not immediately solve the emissions problem, biomass-based coal substitutions require further development until they are ready for large scale production. The data was collected for all 25 Austrian heritage and touristic railways operating with steam locomotives and was divided into a quantitative and qualitative part. Missing data were compensated by research and an extrapolation included railways, where the steam operation was cancelled in the year 2022 due to irregularities. The total carbon dioxide emissions from coal-fired steam locomotive operations in Austria are approximately 3,000 tons per year. Problems in procurement, storage and quality of coal were experienced by a majority of the organizations, while only a minority had experimental or operational experience with alternative firing methods or plans for conversion.

The following thesis aims to assess the inherent potential that cyber-physical systems hold in creating a more sustainable management of waste. For this reason, an upscaling model is derived in which the possible ecological as well as economical changes brought about by two localized Industry 4.0 projects are upscaled onto a larger region. Industrial Revolutions are commonly associated with developments in urban areas. Despite affecting the society as a whole, their impact on rural regions is not often subject of research. Nevertheless, innovations of both pioneer projects have been tested in rural municipalities, providing an interesting research setting, primarily as a result of its relative obscurity. This approach is maintained throughout this work. Moreover, inherent urban-rural differences pose very particular demands on waste management. Generalised deductions of outcomes obtained from rural areas might therefore be ineligible to urban sites. Ultimately, digital transformation undeniably spurs new innovations. The outcome of the Utopian Model contributes to the understanding of changes possible by the digital transformation within the waste management system.

Erneuerbare Energien wie Photovoltaik spielen bereits eine wichtige Rolle in der heutigen Energieversorgung. Das werden sie auch in Zukunft tun, vor allem in Anbetracht auf den Klimawandel. Vorhersagen über die Produktionsmengen sind aus mehreren Gründen wichtig, zum Beispiel um Netzstabilität zu gewährleisten, Handelsbedingungen zu verbessern oder Instandhaltung zu planen.Das Ziel dieser Arbeit ist es, herauszufinden, welche Machine Learning Methoden gut geeignet sind, um die Energieproduktion von Photovoltaikanlagen auf kurze Zeit vorauszusagen. Des Weiteren wurden die Einflüsse von Features in den Daten, wie zum Beispiel Einstrahlung, Regen oder Modultemperatur, erforscht.Ein wichtiger Teil dieser Arbeit war die Vorverarbeitung der Daten. Die Rohdaten der Photovoltaikanlagen wurden dabei so aufbereitet, dass sie von Machine Learning Modelle gut verarbeitet werden können. Dies beinhaltet mehrere Schritte, wie das Auswählen von Features, das Filtern bestimmter Werte und das Hinzufügen von Metafeatures.Es gibt viele Machine Learning Modelle mit unterschiedlicher Komplexität, die ihre jeweiligen Stärken und Schwächen haben. Wir führten Experimente mit verschiedenen Modellen durch, nämlich mit linearer Regression, Regression Trees, neuronalen Netzen und Support Vector Maschinen.Um festzustellen, welche der erprobten Modelle am besten geeignet sind um photovoltaische Energieproduktion vorherzusagen, wurden Experimente mit mehreren Konfigurationen durchgeführt. Dabei wurden zwei Datensätze von zwei unterschiedlichen Kraftwerken in Österreich untersucht, eines in Burgenland und eines in Bisamberg. Darüber hinaus wurde der Einfluss einzelner Features aus den Daten auf die Qualität der Vorhersagen geprüft, indem bestimmte Features entfernt oder isoliert wurden. Die Modelle aus den Experimenten wurden getestet und basierend auf Metriken, die aus der Vorhersagen dieser Tests berechnet wurden, bewertet. Diese Metriken ermöglichen es, die erprobten Modelle zu vergleichen sowie diese Arbeit mit ähnlichen gegenüberzustellen.In unseren Experimenten haben mehrlagige Perzeptronen die besten Ergebnisse in den meisten Metriken erzielt. Regression Trees und lineare Regression konnten auch gute Vorhersagen treffen.Bezüglich der Relevanz von Features ist eine gute Einstrahlungsvorhersage das wichtigste Feature, um die Energieproduktion genau vorherzusagen. Für einen der Datensätze war es allerdings auch möglich, gute Vorhersagen zu treffen, wenn alle anderen Features verwendet wurden. Renewable energy resources such as photovoltaics already play a significant role in our energy supply and will continue to do so in the future, especially with regards to fighting climate change. Forecasting the amount of production is important for multiple reasons such as ensuring grid stability, improving trading conditions or scheduling maintenance.The aim of this work is to find out which machine learning methods are well suited for predicting short term photovoltaic power production. Moreover, we aim to investigate the effects that features such as radiation, rain or module temperature have.A major part of this work was doing preprocessing, i.e$.$ making the data provided by power plants more suitable to be used for learning. This includes multiple steps such as selecting features, filtering certain values and adding meta features. There are multiple machine learning models with varying complexity and unique strengths and weaknesses. We experimented with different models, namely linear regression, regression trees, neural networks and support vector machines.To determine which of the tried models are best suited for predicting photovoltaic energy production, experiments with multiple configurations were run to build different models. These experiments were run on datasets from two seperate power plants in Austria, one from Burgenland and the other from Bisamberg. Furthermore, the influence of different features on the prediction quality was assessed by isolating and removing certain features. The models are tested and evaluated based on metrics caluclated by the predictions obtained from our tests. This allows us to compare them to each other and enables comparisons to similar works.In our experiments, multi-layer perceptrons ended up generally performing the best among most metrics. Regression trees and linear regression also produced good results. Regarding the impact of features, a good radiation forecast is the most important feature in making high quality predictions on produced energy. For one of the datasets, however, it was still possible to make decent predictions using all other features.

Arbeit an der Bibliothek noch nicht eingelangt - Daten nicht geprueft - gesperrte Arbeit (bis 2026-06-17+02:00) Abweichender Titel nach Übersetzung der Verfasserin/des Verfassers

For various planning and policy issues the estimation of future development of heating and cooling demand is of great importance. In this paper we provide exemplary model results for the development of heating and cooling demand for 31 European countries which have been developed in the project Mapping and analyses for the current and future (2020 - 2030) heating/cooling fuel development. (See Fleiter, T.; Steinbach, J.; Ragwitz et.al.). Within this article we focus on the analysis of relevafornt indicators such as the development of total heat demand, specific heat demand per m2, shares of the end use categories space heating, water heating and space cooling as well as renewable shares and CO2 emissions. Additionally to the descriptive part of this study in which we want to provide a snapshot on heating and cooling demand in the European Heating and cooling demand we also discuss potentials for additional CO2 reduction potentials of the residential building stock.

The delicate ecosystem of the Gal��pagos archipelago, a world natural heritage because of its unique biodiversity, appreciated by virtue of Charles Darwin's research, is under threat. Flourishing tourism, a growing population and economic development have increased fossil fuel consumption and dependence. The supply of energy has primarily been based on diesel; while during the last ten years, there have been several initiatives to implement renewable energies (REs) on Gal��pagos. These have been receiving international support after the accident of the oil tanker Jessica in 2001 showed the possible damage oil spills can cause to the delicate ecosystem. In 2007, the Ecuadorian government emphasized the goal to change the energy matrix by announcing the "Zero Fossil Fuel Program for Gal��pagos". Since then, some of the fossil fuels have been successfully replaced through the implementation of wind energy on San Crist��bal and vegetable oil on Floreana. Additional initiatives plan to repower the solar park on Floreana, to install wind turbines on Baltra, and solar photovoltaic on Santa Cruz, Isabella and Baltra. The goal of this thesis is to assess the sustainability of the current strategy towards a 100% RE-System and to find out why despite these efforts, fossil fuels have not yet been completely removed. For this purpose, adequate sustainability criteria are defined from the outset and are organized around the four major dimensions: technological feasibility, energy security, socio-economic energy equity and environmental sustainability. Based on these the sustainability of the electricity systems of all four of the populated islands are analyzed. This research found that the deployment of RE technologies could not only support the global combat against climate change by reducing CO2 emissions and mitigate other negative effects connected to fossil fuel combustion, but additionally could also increase socioeconomic energy equity by promoting prosperity, increasing affordability and improving quality of life. From this comprehensive analysis, a set of recommendations are formulated and these suggestions aim at providing an inspiration to reconsider and reformulate the Zero Fossil Fuel Program for the Gal��pagos with a view towards creating a reliable, affordable, environmentally friendly and socially inclusive energy system.

Germany’s political goal of becoming a decarbonized economy by mid-century can only be achieved by substantially increasing installation rates of on shore wind power plants. But the installation of wind power plants is getting more and more politicized in the German discourse.Wind energy conflicts are on the rise which slows down or in some cases even hampers project approvals and implementation. A relevant dilemma arises for the necessary energy transition.Social acceptance is becoming a strategically important issue that needs to be addressed by project developers. In this master thesis a conflict model will be developed and presented, that aims to provide an easy-to-use analysis tool that helps to holistically understand, get better prepared and potentially mitigate wind energy conflicts. Local wind energy conflicts will be described as conflict arenas, where (seen from a bird’s perspective) different groups of people are using different strategies and arguments to fight for their interests, power and beliefs. In total five archetypical groups within this conflict arena will be identified. A methodological and intellectual equidistance will be practiced towards the different positions of those groups to ensure a deeper and unbiased understanding of the conflict actors and dynamics. Within any local wind energy conflict arena in Germany there are up to seven different types of arguments that are being exchanged between stakeholders to fight for political influence and opinion leadership. Those seven argumentation patterns are being used and exchanged with the overall aim to influence the dynamics within the local conflict arena into the direction of oneown’s beliefs and interest. Those seven argumentation patterns or conflict dimensions will be called the ’Local Wind Energy Conflict Heptagon’ and they are revolving around the following topics: 1. The democratic quality and transparency of project approval processes (‘Democratic Procedures’) 2. Considerations on profit sharing and investment offers for municipalities and members of the affected communities (‘Fair Share’) 3. Questions concerning impacts on human health (‘Health First’) 4. Ecological impacts of wind power plants (‘Ecological Responsibility’) 5. The level of trust between key stakeholders and community members(‘Trustful Relations’) 6. The aesthetical impacts on landscapes (‘Respect for Local Identities’)7. The way broader questions on climate change and renewable energies are being discussed on local level (‘Debating Climate Change and Renewable Energies’). Not in every wind energy conflict all seven dimensions will be ‘activated’ and therefore will be influencing the conflict. It might be that only one or two dimensions really become important and decisive for the outcome of the conflict. But for project developers it is necessary to oversee and be prepared for all conflict dimensions. The success of a project implementation will (inter alia) depend on the anticipatory qualities of project management as well as strategic decision-making and positioning within this conflict arena. Being one step ahead of everyone else, can be a keyelement for a successful and friction-free project implementation.