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Entwicklung einer Methode zur modellbasierten Vorauslegung der Energiesysteme eines wasserstoffbetriebenen Propeller-Flugzeuges
Get PDFDiese Arbeit analysiert die Flugzeugsysteme eines Wasserstoffflugzeuges. In der ersten Phase wird ein ATR72-600 als wasserstoffbetriebene Variante mit Brennstoffzellen nachdimensioniert. Anschließend werden die Anpassungen der Systeme aufgrund des Treibstoffwechsels durchgeführt. Für das Treib-stoffsystem und die Klimanlage werden die thermodynamischen Vorgängen analytisch beschrieben. Die Modellierung zusammen mit dem Antriebssystems durch Brennstoffzellen und des elektrischen Systems ist mit der Simscape Umgebung in MATLAB Simulink geplant. Aufgrund zeitlicher Begrenzung ist das Modell nicht vollständig und konnte nicht mehr an dem Referenzflugzeug getestet werden.This report considers the aircraft systems of an hydrogen powered aircraft. In the first part, a preliminary design of an hydrogen powered version of the ATR72-600 with fuel cells is accomplished. Due to use of hydrogen as fuel, the adjustments in the aircraft systems are discussed. The thermodynamic processes of the fuel system and the ECS are described with an analytical method. The model the these systems, including the fuel cell system and the ECS is implemented with the Simscape environment in MATLAB
Simulink. Due to the lack of time, the model couldn´t be finished and an evaluation of the pre-designed reference aircraft Considering the limited time, the model couldn´t be completed and an evaluation of the previously mentioned reference aircraft wasn´t possible
Jugendbeteiligung in Hamburg : zehn Perspektiven aus Sicht von Jugendlichen
Get PDFBehörde für Wissenschaft, Forschung, Gleichstellung und BezirkeNonPeerReviewe
Benjamin, Deleuze, and the Baroque : the early modern origins of media theory
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Mit der Blockchain zu sicheren Liefernetzwerken
No full textKleine und mittlere Unternehmen (KMU) können durch Blockchain-Technologie ihre Liefernetzwerke sicherer und transparenter gestalten. Dies wird am Beispiel eines Demonstrators des Mittelstand-Digital Zentrums Hamburg aufgezeigt, der Echtzeit-Tracking, verbesserte Transparenz und Datenqualität sowie reduzierten manuellen Aufwand ermöglicht.Bundesministerium für Wirtschaft und KlimaschutzNonPeerReviewe
Impact of packaging color on choice and health perception : insights from chickpeas and ravioli in Germany
Get PDFThe global rise in obesity linked to poor nutrition behavior underscores the importance of promoting a healthy diet. This study investigates the impact of packaging color on consumer choice and health perception of chickpeas (a healthy product) versus ravioli (an unhealthy product) in Germany. Two choice experiments (CEs) were conducted with 222 participants aged 19 to 35, examining the influence of packaging color, label, price, and origin on product selection. Additionally, an image query assessed health perceptions associated with six different colored chickpea cans.
The results indicate that price is the most influential factor in product choice for both chickpeas and ravioli, while packaging color has the least influence. However, green packaging significantly enhances health perception, with participants associating it with healthiness and environmental friendliness. In contrast, red packaging does not convey health value and is not linked to healthiness. Light blue packaging negatively affects health perception, partly due to associations with artificial additives. Beige packaging slightly improves health perception, while silver and black are perceived as indicators of quality but can also make the product appear less healthy.
These findings highlight the complex role of packaging color in consumer behavior and suggest that while price remains a dominant factor, strategic use of color can enhance health perceptions and potentially influence healthier food choices. Future research should explore these effects across different cultural contexts and incorporate psychophysical methods to further understand the underlying mechanisms of color perception.PeerReviewe
Charging infrastructure power requirements for flexibility usage
Get PDFScenarios with differently dimensioned charging capacity are examined with regard to the utilization of the flexibility potential of heavy commercial vehicles. These vehicles are only charged at the depot during idle times. The comparison of the scenarios illustrates how strongly the increase in flexibility potential depends on the dimensioning of the charging infrastructure. The lower extreme is determined by the size of the charging time window. If it is fully utilized, no flexibility can be achieved. A brief economic classification of the investment costs for charging infrastructure with the same number of charging points is given. It was shown, that economic obstacles exist for ascending the flexibility potential and incentives are required for counter-financing.Bundesministerium für Digitales und VerkehrPeerReviewe
Failure of Engine Generators on A320 Family Aircraft
Get PDFAirbus wurden einige Fälle von elektrischen Notkonfigurationen bei A320-Flugzeugen gemeldet, bei denen beide Triebwerksgeneratoren (Integrated Drive Generator, IDG) aufgrund verschlissener Komponenten in ihrem Konstantdrehzahlgetriebe (Constant Speed Drive, CSD) nacheinander ausfielen. Wie sich herausstellte, können verschlissene IDGs unter bestimmten Umständen zu Problemen mit der Frequenzregelung führen, was dann die elektrische Notkonfiguration aktiviert. Vorbeugende Wartungsarbeiten wurde definiert, um verschlissene IDGs im Voraus zu erkennen. Den Flugbesatzungen werden Empfehlungen gegeben, um eine mögliche elektrische Notkonfiguration im Falle eines Generatorausfalls zu verhindern.Airbus has been notified of several cases of electrical emergency configurations on A320 aircraft, in which both engine generators (Integrated Drive Generator, IDG) failed consecutively due to worn components in their Constant Speed Drive (CSD). As it turns out, worn IDGs can, under certain circumstances, cause frequency control issues, which then activate the electrical emergency configuration. Preventive maintenance tasks have been defined to detect worn IDGs in advance. Flight crews are provided with recommendations to prevent a possible electrical emergency configuration in the event of a generator failure.NonPeerReviewe
Mode – Kleidung – Textil : Kulturwissenschaftliche Grundlegung und Methode
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Wind desalination and power : an affordable and renewable solution to address water shortages
No full textThere has been a steep increase in investment in more affordable approaches to desalinated seawater using renewable energy sources. This paper proposes desalinating seawater with a pump and a motor-generator installed inside wind turbine nacelles, to desalinate seawater with reverse osmosis membranes without electricity. The technology was named Wind Desalination and Power (WDP), as the wind turbine can pump seawater and generate electricity. This study presents a comprehensive analysis and rationale behind the design, estimates its economic viability, and assesses the global potential of the proposed technology. Results demonstrate that the cost for seawater desalination with WDP is 0.64 USD/m3, which is 20% cheaper than conventional wind desalination. The paper shows that WDP has the potential to enhance water resilience in arid regions while at the same time contributing to grid stability and renewable energy integration.PeerReviewe
Untersuchung von Machine Learning Algorithmen auf einem FPGA zur Klassifikation
Get PDFIn dieser Bachelorarbeit werden der k-nächste Nachbar Algorithmus, binarisierte neuronale Netze und Entscheidungsbäume zur Klassifikation mittels FPGA untersucht. Durch Abwägung und Untersuchung der einzelnen Algorithmen wird der Entscheidungsbaum als besonders geeignet befunden. Ein Entscheidungsbaum wird auf einem FPGA implementiert und getestet. Der MNSIT-Testdatensatz konnte mit einer Genauigkeit von 88,47 % klassifiziert werden. Dabei wurden die FPGA Ressourcen kaum ausgelastet.In this bachelor thesis, the k-nearest neighbor algorithm, binarized neural networks and decision trees for classification using FPGA are investigated. By consideration and examining the individual algorithms, the decision tree is found to be particularly suitable. A decision tree is implemented and tested on an FPGA. The MNSIT test data set could be classified with an accuracy of 88.47 %. The FPGA resources were hardly utilized