J. Computer Applications
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Der anthropogene Klimawandel erfordert drastische Maßnahmen zur Reduzierung von Treib-hausgasemissionen, insbesondere im Verkehrssektor. Alternative Antriebe wie batterieelektri-sche Fahrzeuge sind vielversprechend, auch für den Rettungsdienst, der derzeit überwiegend Fahrzeuge mit Verbrennungsmotoren nutzt. Ein Hindernis für die Einführung von batterie-elektrischen Rettungswagen ist die begrenzte Reichweite. Ziel dieser Arbeit ist die Entwicklung einer Methodik zur Ermittlung, ob und welche konventionell betriebenen Rettungswagen unter welchen ladeinfrastrukturellen Voraussetzungen durch batterieelektrische Rettungswagen er-setzt werden können. Konkret wird untersucht, welche der neun im Ilm-Kreis stationierten Ret-tungswagen durch das Modell „WAS 500 E-Ambulanz“ ersetzt werden können und welche Ladeinfrastruktur dafür notwendig ist.
Die Analyse basiert auf Einsatzfahrtdaten der Rettungswagen im Ilm-Kreis aus dem Jahr 2022. Fehlende Daten wurden durch Imputation ergänzt. Die Methodik umfasst die Entwicklung ma-thematisch-physikalischer Modelle zur Simulation des Ladezustands der batterieelektrischen Rettungswagen unter den zwei Szenarien: „Ladeinfrastruktur nur an Rettungswachen“ und „Ladeinfrastruktur an Rettungswachen und Krankenhäusern“. Herausforderungen bestehen in den Datenlücken und der Qualität der vorhandenen Daten. Die Modellierung weist Einschrän-kungen aufgrund der Datenqualität und Vereinfachungen realer Bedingungen auf. Eine Mo-dellvalidierung war nur grundlegend möglich. Die Methodik kann auf andere Untersuchungs-gebiete übertragen werden, sofern die Parameter angepasst werden und eine ausreichende Datenqualität gewährleistet ist. Zielgruppe sind Entscheidungsträger im Rettungsdienst und bei der Fahrzeugbeschaffung.
Die Simulation zeigt, dass keiner der Rettungswagen im Ilm-Kreis einschränkungslos ersetzt werden kann. Hauptursachen sind aufeinanderfolgende Einsatzfahrten ohne ausreichende Zwischenladung und Einsätze mit Gesamtverbräuchen über der maximalen Batteriekapazität. Im Szenario „Ladeinfrastruktur nur an Rettungswachen“ liegt die Ausfallrate zwischen 1,71 % und 4,9 %, während sie im Szenario „Ladeinfrastruktur an Rettungswachen und Krankenhäu-sern“ auf 0,14 % bis 0,91 % sinkt. Unter der Voraussetzung der Einhaltung bestimmter Ein-schränkungen ist es möglich, im Rahmen des Szenarios „Ladeinfrastruktur an Rettungswa-chen und Krankenhäusern“ vier Rettungswagen durch batterieelektrische Rettungswagen zu ersetzen. Die Einschränkungen umfassen eine Anpassung der Dispositionsstrategie sowie die fortlaufende Vorhaltung konventioneller Rettungswagen an anderen Standorten. Weitere For-schung ist notwendig, um die Modellgenauigkeit zu verbessern und die genauen Auswirkun-gen angepasster Dispositionsstrategien zu untersuchen. Zukünftige Praxistests und Wirt-schaftlichkeitsanalysen sind erforderlich, um die umfassende Eignung von batterieelektrischen Rettungswagen sicherzustellen.
Diese Arbeit befasst sich mit der immer vorhandenen Gefahr durch Cyberkriminelle auf Anwendungen und Informationssysteme. Die Informationssicherheit ist ein sehr umfangreiches Thema und sieht sich in der heutigen Zeit besonders starken Gefahren ausgesetzt, die durch die voranschreitende Digitalisierung immer gängiger werden. Durch ein gut eingerichtetes Datenbanksystem und einer gut entwickelten Datenbankanwendung soll es Anwendern ermöglicht werden, die Sicherheit dieser zu bewahren. Hierbei spielen Themen wie Authentifizierung, Zugriffskontrolle, PL/SQL Best Practices und Audits sowie Backups eine zentrale Rolle. Das Einrichten interner und externer Schutzmaßnah-men, explizit auch der Schutz vor SQL-Injektionen, sind die in dieser Arbeit zu behan-delnden Themen. Durch den korrekten Einsatz der prozeduralen Erweiterung von SQL sollen Schutzmechanismen erforscht und demonstriert werden, die eine Umfangreiche Bandbreite von potenziellen Angriffen abdecken können. Das Verständnis für den Einsatz der korrekten Verfahren soll über eine Methode, genannt Systematisches Risikomanagement, erörtert werden. In diesem Kontext werden Risiken identifiziert, um passende Lösungsvorschläge zu erforschen und zu präsentieren, um im Nachhinein ihren genauen Einsatz zu diskutieren. Durch den Einsatz der vorgestellten Methoden, Konzepte und Modelle soll die Sicherheitslandschaft im Bereich Informations- und Kommunikationstechnik optimiert werden, um einen soliden Schutz gegen präsente Gefahren zu leisten.
The decarbonization and the substitution of fossil fuels with hydrogen have emerged as critical objectives in the ongoing energy transition. However, the lack of understanding and awareness surrounding industrial-scale hydrogen projects and their potential hinder progress in addressing these challenges. To expedite the transition process, it is imperative to cultivate a sense of awareness and sensitivity among industrial-scale hydrogen projects, dimensions of generation plants, and potential use cases for hydrogen and its co-products from electrolysis.
This research endeavors to answer the fundamental question: "How can a general sense of awareness and sensitivity for hydrogen projects be established in a manner that is easily comprehensible?" To accomplish this goal, a systematic approach is proposed. The research leverages renewable generation profiles in hourly resolution data from photovoltaic plants and onshore/offshore wind turbines, to ascertain the available electricity that can be utilized for electrolysis. By employing scientifically grounded assumptions about the parameters of electrolysis plants, the design and resource requirements will be determined and visually represented. Additionally, predefined use cases for the produced hydrogen and its by-products will be considered, and diverse supply capacities will be visualized across sectors such as mobility, industry, and housing, considering in non-cumulative manner. In addition, the potential of hydrogen as a long-term storage media for renewable electricity can be assessed.
The outcome of this research manifests as an accessible web tool called the "Electrolysis Calculator". This user-friendly tool necessitates four user-input values and performs calculations for primary electrolysis design parameters, encompassing full-load hours, resource consumption, generated energy, and substance quantities. Furthermore, the web tool provides intuitive visualizations of typical use case capacities, aimed at fostering awareness and understanding of hydrogen projects among its users.
The web tool enables decision-making and promoting widespread adoption of hydrogen as an alternative energy carrier and long term storage media.
This bachelor thesis addresses the issue of how school resilience can be measured and assessed quantitatively. Schools as social infrastructures have a significant value for society. Yet, on a global scale, they, and therefore the respective community as well, are continuously endangered by a variety of threats such as natural disasters or violence and mental abuse affecting students, parents and school staff. However, these threats differ greatly depending on climatic and geographical conditions as well as on the socio-cultural context of the corresponding community. To strengthen school resilience against potential threats and to ensure education continuity despite the occurrence of these disruptions, a methodology is developed to measure and assess school resilience in conjunction with its specific circumstances. Initially, qualitative and quantitative (composite) indicators are identified and categorised with the help of a Systematic Literature Review and Mayring's Qualitative Content Analysis. These are subsequently developed into a Comprehensive Index for School Resilience (CISR). Building on this, a pre-existing assessment methodology, which uses Likert-Scales arranged in questionnaires to assign quantitative values to the composite indicators, is adapted to operationalise the CISR and by an exemplary application at Europaschule Troisdorf, the methodology is adapted to the socio-cultural conditions in Germany using an expert’s operational and contextual knowledge. The results obtained show that the methodologies and techniques described in current international research can, after an appropriate adaptation, successfully be applied to schools in Germany as well. Nevertheless, by identifying research limitations and errors as well as potential improvements, it is evident that further research and development is needed to provide stakeholders with a decision-making tool to strengthen the resilience of schools in the future, such as an exhaustive supplement to the CISR or the integration of more precise quantification methodologies and techniques.
A test tool for Langton's ant-based algorithms is created. Among other things, it can create test files for the NIST-Statistical-Test-Suite. The test tool is used to investigate the invertibility, ring formation and randomness of 7 created models which are extensions of Langton’s ant. The models are examined to possibly use them as pseudo-random generator (PRG) or block cipher. All models use memories which are based on tori. This property is central, because this is how rings are formed in the first place and in addition the behavior of all models at the physical boundaries of the memory is clearly defined in this way. The different models have special properties which are also investigated. These include variable color sets, discrete convolution, multidimensionality, and the use of multiple ants, which are arranged fractal hierarchically and influence each other. The extensions convolution, multidimensional scalable and multidimensional scalable fractal ant colony are presented here for the first time. It is shown that well-chosen color sets and high-dimensional tori are particularly well suited as a basis for Langton's ant based PRGs. In addition, it is shown that a block cipher can be generated on this basis.
With Google’s Flutter framework continuing to grow in popularity for companies and developers alike, the need for an understanding of how to utilize the framework in a large-scale context has become more relevant than ever. The purpose of this thesis is to document the crucial steps most development teams using Flutter in a large-scale application will face. Additionally, a fully documented, large-scale reference application was generated so that other developers may use it as an aid when creating their own Flutter projects on a similar scale. Multiple steps were taken to ensure that optimal solutions were chosen for each aspect of the development process. For each of those aspects, a wide range of possible solutions were explored, compared and analysed. Finally, one of the possible solutions was chosen based on a wide range of scientific papers and community-generated sources. Additionally, an interview with an expert in the field was conducted to further validate those decisions. After the application was fully implemented, ten crucial aspects of the development process were identified. Those ten aspects are now explained in detail in this thesis. Ultimately, the knowledge provided by this thesis can act as a map for peers using Flutter in a large-scale context and help them overcome the crossroads they will most likely come to face.
Das Internet of Things (IoT) ist aktuell eines der trendgebenden Themen der Infor-mationstechnik. Dem Thema werden dabei viele Versprechungen, aber auch Erwar-tungen auf staatlicher, wirtschaftlicher und alltäglicher Ebene zugeordnet. Dabei besteht die Frage, was ist Hype und was ist Realität? Motivation und Zielsetzung dieser Arbeit ist es, dieses Thema zu untersuchen und Aspekte daraus in einem Smart Home System umzusetzen. Klare Zielsetzung ist die lauffähige Ver-sion eines Prototyps zu produzieren. Dieser soll den technischen Durchstich ver-schiedener Werkzeuge, Technologien und Services, als integratives Ziel dieser Arbeit, durchführen. Eine Verknüpfung mit realen Anwendungsfällen ist zur besse-ren Veranschaulichung wünschenswert, aber für die Zielerreichung nicht zwangsläu-fig erforderlich. Gleichzeitig soll der Prototyp ein stabiles Fundament für weitere Entwicklungen auf dessen Basis bereitstellen. Der Einsatz von Technologien im Be-ta-Stadium ist dadurch aber nicht ausgeschlossen, wie der Einsatz des aktuell noch in der Entwicklervorschau befindlichen Android Things zeigt.
This thesis presents the perspective and basis for modeling of retail electricity price components in Germany. Detailed Python models are developed to provide predictions for yearly development of average network charges, EEG, StromNEV-19 and KWK surcharges for the period 2015-2035. For network charges and EEG surcharge, scenario-B (2035) from NEP2015 has been chosen as the model scenario. For KWK surcharge, the 2025 KWK share target, set by KWKG-2016, has been chosen as the model scenario. Individual component model results are validated against available academic literature and institutional reports. Model results for EEG surcharge, indicate an increasing yearly EEG costs till 2024, after which the expiring EEG plants of past will unburden the related high costs and EEG surcharge will drop but still be around 99% of 2015 level in 2035. Model results for network charges indicate a consistently increasing yearly trend owing to high grid investments needed for reaching the target RE share of 57%. KWK model results also indicate a growing KWK surcharge until 2020 which then would remain stagnant at that level onwards. All model results are collected under three consumption categories, namely, households, privileged and nonprivileged industries. The final results indicate that the average German household will face an overall increase of around 3.37 Cents/kWh in retail electricity prices (excluding VAT) till 2028, after which the retail prices will drop a little due to dropping EEG surcharge. The similar but slightly reduced trend can be seen for nonprivileged industrial consumption. The increment effect, however, is only minute for privileged industrial consumption due to high exemptions in EEG & KWK surcharges and reduced individual network charges.
There is a dramatic shift in credit card fraud from the offline to the online world. Large online retailers have tried to establish countermeasures and transaction data analysis technologies to lower the rate of fraudulent transactions to a manageable amount. But as retailers will always have to make a trade-off between the performance of the transaction processing, the usability of the web shop, and the overall security of it, one can assume that e-commerce fraud will still happen in the future. Thus, retailers have to collaborate with relevant business partners on the incident to find a common ground and take coordinated (legal) actions against it.
Trying to combine the information from different stakeholders will face issues due to different wordings and data formats, competing incentives of the stakeholders to participate on information sharing, as well as possible sharing restrictions that prevent them from making the information available to a larger audience. Moreover, as some of the information might be confidential or business-critical to at least one of the parties involved, a centralized system (e.g. a service in the public cloud) can not be used.
This Master Thesis is therefore analysing how far a computer supported collaborative work system based on peer-to-peer communication and Semantic Web technologies can improve the efficiency and effectivity of e-commerce fraud investigations within an inter-institutional team.