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Changing our unsustainable linear water management pattern is necessary to face growing global water challenges. This article proposes an integrated framework to analyse and understand the role of different contextual conditions in the possible transition towards water circularity. Our framework combines a systematic multi-level perspective to explore the water system and the institutional work theory for technology legitimation. The framework consists of the following stages: (1) describing and understanding the water context, (2) assessment of the selected technologies’ circularity level, (3) assessment of the alternative circular technologies’ legitimacy, and (4) identification of the legitimation actions to support the upscale of alternative circular technologies. The practical applicability of the integrated assessment framework and its four assessment stages was demonstrated in the exploration of circular water technologies for the horticulture sector in Westland, the Netherlands. The results revealed the conditions that hinder or enable the legitimation of the circular water technologies, such as political environmentalism, trust in water governing authorities, and technical, financial, and knowledge capabilities.
This market research paper has been prepared under the supervision of Prof. Dr. Wolfgang Veit of TH Köln and Prof. Dr. Carol Scovotti of University of Wisconsin-Whitewater in the course of the inter-university cross-border collaboration student research project “Export Opportunity Surveys (EOS)”. This study explores organic canned tomatoes export opportunities to the German and US markets.
Information ist in den vergangenen Jahren zu einem immer wichtigeren Element unseres Wirtschaftens geworden. Sei es eher sekundär, als Information über Güter, oder als eigenständig vermarktbares (Primär-)Gut. Trotz seiner steigenden Bedeutung hinkt die wissenschaftliche Auseinandersetzung mit diesem wichtigen Wirtschaftsfaktor deutlich hinterher. Es ist noch lange kein Allgemeinplatz, dass sich Informationsgüter nicht auf die gleiche Art und Weise erstellen und anbieten lassen wie es für die uns schon lange vertrauten physischen Güter der Fall ist. Es ist eben nicht das gleiche, ob man einen Bleistift oder eine Information, z. B. über die Marktstellung eines Unternehmens, kauft. Vier verschiedene Aspekte lassen sich aus einer ökonomischen Perspektive identifizieren, die für diese Unterschiede ursächlich sind und dazu führen, dass Anbieter von Informationsgütern anders am Markt agieren müssen.
Forschungsfrage: Wie wirken sich autoritäre, kooperative und laissez-faire Führungsstile auf die Pro-duktivität und Arbeitseinstellung der Mitarbeitenden im digitalen Arbeitskontext aus?
Methodik: Gestaffelte quantitative Inhaltsanalyse zur Führungsstilermittlung und zur Auswirkung in digital basierten Arbeitsbeziehungen Praktische Implikationen: Im digitalen Arbeitskontext wirkt sich der kooperative Führungsstil sowohl auf die Produktivität als auch auf die Arbeitseinstellung am stärksten positiv aus.
Die nachfolgende Masterarbeit untersucht die Nutzung von DeepFake-Anwendungen bei Personen mit einer Fazialisparese. Dabei handelt es sich um eine Lähmung des Gesichtnervs, wodurch die betroffenden Menschen keine bzw. keine vollständige Mimik im Gesicht haben. Es wird hierbei getestet, ob mithilfe von DeepFake eine möglichst realistische Mimik generiert werden kann. Für die Untersuchung werden zunächst sowohl die theoretischen Grundlagen als auch verschiedene potenzielle Anwendungen vorgestellt. Mithilfe der vorgestellten Anwendungen wird anschließend ein Versuch durchgeführt, in dem die künstliche Intelligenz mit Bildmaterial von Proband:innen trainiert und anschließend manipuliert wird. Die aus dem Versuch resultierenden Ergebnisse werden danach durch eine Umfrage mit Bildern, welche eine originale Mimik zeigen, verglichen. Dadurch soll überprüft werden, wie realistisch die manipulierten Bild- und Videomaterialien sind oder ob die künstliche Intelligenz an eine mögliche Grenze stößt. Abschließend werden weitere Forschungsansätze und Anwendungsmöglichkeiten vorgestellt, in welchem die betrachtete künstliche Intelligenz genutzt werden kann.
This market research paper has been prepared under the supervision of Prof. Dr. Agnieszka Gehringer of TH Köln and Prof. Dr. Carol Scovotti of University of Wisconsin-Whitewater in the course of the inter-university cross-border collaboration student research project “Export Opportunity Surveys (EOS)”. This study explores organic oranges export opportunities to the German and US markets.
Decisions on irrigation water management are usually made at different levels, including farms, water user associations (WUAs), and regional water planning agencies. The latter generally have good access to information and decision tools regarding water resources management. However, these remain out of reach to the final water users, namely the farmers. The study, conducted in the irrigated district of Cherfech, north Tunisia, had the main objective of investigating farmer’s perceptions of, and acceptance for, the use of an irrigation advisory service (IAS) to be implemented by their WUA. The suggested IAS provides the following information: (1) reference evapotranspiration (ETo) and rainfall; (2) crop water requirement (CWR) of the most cultivated crops; (3) irrigation water requirement (IWR) of the farmer’s crop; and (4) crop monitoring and real-time estimation of IWR of crops settled, using soil moisture sensors. Such services and information would be available at the WUA level and provided in a timely manner to farmers for more effective decision making at the plot level. Prior to the acceptance study, we launched a technical study to determine the required tools and equipment required for the implementation of the IAS, followed by a farmer survey to assess their respective perceptions and acceptance towards this IAS. Results showed that only 54% of the farmers are satisfied by WUAs work, but that 77% of them accepted using the suggested IAS. Farmers are also willing to pay for most of the IAS packages suggested. The financial profitability of investing in the IAS at the WUA level shows the venture is financially viable, with a benefit cost ratio (BCR) of 1.018. The project will be even more profitable if we add the social benefits, which may result in water savings at the WUA level.
Water scarcity drives governments in arid and semi-arid regions to promote strategies for improving water use efficiency. Water-related research generally also plays an important role in the same countries and for the same reason. However, it remains unclear how to link the implementation of new government strategies and water-related research. This article’s principal objective is to present a novel approach that defines water-related research gaps from the point of view of a government strategy. The proposed methodology is based on an extensive literature review, followed by a systematic evaluation of the topics covered both in grey and peer-reviewed literature. Finally, we assess if and how the different literature sources contribute to the goals of the water strategy. The methodology was tested by investigating the impact of the water strategy of Jordan’s government (2008–2022) on the research conducted in the Azraq Basin, considering 99 grey and peer-reviewed documents. The results showed an increase in the number of water-related research documents from 37 published between 1985 and 2007 to 62 published between 2008 and 2018. This increase should not, however, be seen as a positive impact of increased research activity from the development of Jordan’s water strategy. In fact, the increase in water-related research activity matches the increasing trend in research production in Jordan generally. Moreover, the results showed that only about 80% of the documents align with the goals identified in the water strategy. In addition, the distribution of the documents among the different goals of the strategy is heterogeneous; hence, research gaps can be identified, i.e., goals of the water-strategy that are not addressed by any of the documents sourced. To foster innovative and demand-based research in the future, a matrix was developed that linked basin-specific research focus areas (RFAs) with the MWI strategy topics. In doing so, the goals that are not covered by a particular RFA are highlighted. This analysis can inspire researchers to develop and apply new topics in the Azraq Basin to address the research gaps and strengthen the connection between the RFAs and the strategy topics and goals. Moreover, the application of the proposed methodology can motivate future research to become demand-driven, innovative, and contribute to solving societal challenges.
Im Rahmen dieser Bachelorarbeit wurde der von Debevec und Malik verwendete Algorithmus zur Erstellung von HDR-Bildern als Plugin für die Bildverarbeitungssoftware ImageJ implementiert. Darüber hinaus wurde die Implementierung durch Tests auf ihre Funktionalität überprüft und Schwachstellen des Algorithmus erläutert. Durch Modifizierungen des erstellten Plugins wurden einige Schwächen des Algorithmus verbessert.
Das Vorlesebuch bietet Kindern bereits vor der eigenen Lesefähigkeit komplexe
Charaktere an, die als Rollenvorbilder verstanden werden können. Sofern Erzählungen in
pädagogischen Institutionen angeboten werden, wird ihnen schon durch die
professionelle Auswahl aus der Masse möglicher Geschichten ein besonderes Gewicht
verliehen. Dies gilt auch für Narrationen zu Geschlechterrollen. In Medien- und anderen
Produkten werden Mädchen und Jungen mit unterschiedlichen Stereotypen und somit
impliziten Rollenerwartungen konfrontiert. Um herauszufinden welches Bild vom Mädchen
in erzählenden kinderliterarischen Texten durch Protagonistinnen vermittelt werden,
werden jüngste Entwicklungen des Kinderbuchs festgehalten werden. Anschließend wird
das distributive System, in welchem sich das Vorlesebuch befindet genauer betrachtet.
Eine Analyse von vier Vorlesebüchern der umsatzstärksten Kinderbuchverlage soll zeigen, wie sich präadoleszente Protagonistinnen verhalten und ob sich ein
dominierender Mädchentypus abzeichnet. Dabei wird zu zeigen sein, dass die
untersuchten handlungsleitenden Mädchen wissbegierig, kompetent und bestimmend
sind und ein insgesamt aktiver, „starker“ Mädchentypus dominiert
The management of the liquid fraction of digestate produced from the anaerobic digestion of biodegradable municipal solid waste is a difficult affair, as its land application is limited due to high ammonium concentrations and the municipal waste that water treatment plants struggle to treat due to high pollutant loads. The amount of leachate and the pollutant load in the leachate produced by landfills usually decreases with the time, which increases the capacity of landfill leachate treatment plants (LLTPs) to treat additional wastewater. In order to solve the above two challenges, the co-treatment of landfill leachate and the liquid fraction of anaerobic digestate in an industrial-scale LLTP was investigated along with the long-term impacts of the liquid fraction of anaerobic digestate on biocoenosis and its impact on LLTP operational expenses. The co-treatment of landfill leachate and liquid fraction of anaerobic digestate was compared to conventional leachate treatment in an industrial-scale LLTP, which included the use of two parallel lanes (Lane-1 and Lane-2). The average nitrogen removal efficiencies in Lane-1 (co-treatment) were 93.4%, 95%, and 92%, respectively, for C/N ratios of 8.7, 8.9, and 9.4. The average nitrogen removal efficiency in Lane-2 (conventional landfill leachate treatment), meanwhile, was 88%, with a C/N ratio of 6.5. The LLTP’s average chemical oxygen demand (COD) removal efficiencies were 63.5%, 81%, and 78% during phases one, two, and three, respectively. As the volume ratios of the liquid fraction of anaerobic digestate increased, selective oxygen uptake rate experiments demonstrated the dominance of heterotrophic bacteria over ammonium and nitrite-oxidising organisms. The inclusion of the liquid fraction of anaerobic digestate during co-treatment did not cause a significant increase in operational resources, i.e., oxygen, the external carbon source, activated carbon, and energy.
Before transporting the landfill leachate to municipal wastewater treatment plant it has to be treated in a landfill leachate treatment plant, as it comprises high concentrations of ammonium. The elimination of ammonium load in the leachate is usually done by the combined processes of nitrification and denitrification with a specially adapted biocenosis in the activated sludge (AS). For each of the steps, specialized bacteria such as Nitrosomonas, Nitrobacter and Paracoccus are used to transfer the ammonia to gaseous nitrogen. The aim of this investigation was to find suitable process parameters for a complementary treatment of fermentation water from a biogas plant together with landfill leachate. The processed water of the biogas plant consists of a higher concentration of ammonium and carbon sources or easily degradable volatile fatty acids. It can save the usage of external carbon source (acetic acid) and additionally it could also compensate the missing volumes of leachate in times of low rain and low leachate flows. To maintain the high workload for the existing leachate treatment pilot plant (LTPP), a combined treatment of landfill leachate and process water is also of economic and of ecological interest. The long-term adaption process of the biocenosis needs to be done step-by-step. Innovative process monitoring is needed to prevent biocenosis collapse. In our study, we present our set-up, a closer look at the ongoing experiment and the long-term changes in the biocenosis.
Modern industrial biomass combustion plants are regulated by the power and/or combustion control. In this process, the implemented sensors collect the relevant measured data. The aim is to achieve ideal combustion with optimum efficiency and to minimize gas emissions. For this purpose, a group within the research project Metabolon developed new regulatory procedures in order to record the combustion process of a biomass combustion plant using a webcam. The recordings were evaluated automatically and were used for a better monitoring of the process. In addition, the webcam-based method aims, among other things, to provide private homes with a cost-effective variant as an alternative to industrial system solutions.
Agents with antifungal activity play a vital role as therapeutics in health care, as do fungicides in agriculture. Effectiveness, toxicological profile, and eco-friendliness are among the properties used to select suitable substances. Furthermore, a steady supply of new agents with different modes of action is required to counter the well-known potential of human and phyto-pathogenic fungi to develop resistance against established antifungals. Here, we use an in vitro growth assay to investigate the activity of the calcineurin inhibitor tacrolimus in combination with the commercial fungicides cyproconazole and hymexazol, as well as with two earlier reported novel {2-(3-R-1H-1,2,4-triazol-5-yl)phenyl}amines, against the fungi Aspergillus niger, Colletotrichum higginsianum, Fusarium oxysporum and the oomycete Phytophthora infestans, which are notoriously harmful in agriculture. When tacrolimus was added in a concentration range from 0.25 to 25 mg/L to the tested antifungals (at a fixed concentration of 25 or 50 mg/L), the inhibitory activities were distinctly enhanced. Molecular docking calculations revealed triazole derivative 5, (2-(3-adamantan-1-yl)-1H-1,2,4-triazol-5-yl)-4-chloroaniline), as a potent inhibitor of chitin deacetylases (CDA) of Aspergillus nidulans and A. niger (AnCDA and AngCDA, respectively), which was stronger than the previously reported polyoxorin D, J075-4187, and chitotriose. The results are discussed in the context of potential synergism and molecular mode of action.
High-quality rendering of spatial sound fields in real-time is becoming increasingly important with the steadily growing interest in virtual and augmented reality technologies. Typically, a spherical microphone array (SMA) is used to capture a spatial sound field. The captured sound field can be reproduced over headphones in real-time using binaural rendering, virtually placing a single listener in the sound field. Common methods for binaural rendering first spatially encode the sound field by transforming it to the spherical harmonics domain and then decode the sound field binaurally by combining it with head-related transfer functions (HRTFs). However, these rendering methods are computationally demanding, especially for high-order SMAs, and require implementing quite sophisticated real-time signal processing. This paper presents a computationally more efficient method for real-time binaural rendering of SMA signals by linear filtering. The proposed method allows representing any common rendering chain as a set of precomputed finite impulse response filters, which are then applied to the SMA signals in real-time using fast convolution to produce the binaural signals. Results of the technical evaluation show that the presented approach is equivalent to conventional rendering methods while being computationally less demanding and easier to implement using any real-time convolution system. However, the lower computational complexity goes along with lower flexibility. On the one hand, encoding and decoding are no longer decoupled, and on the other hand, sound field transformations in the SH domain can no longer be performed. Consequently, in the proposed method, a filter set must be precomputed and stored for each possible head orientation of the listener, leading to higher memory requirements than the conventional methods. As such, the approach is particularly well suited for efficient real-time binaural rendering of SMA signals in a fixed setup where usually a limited range of head orientations is sufficient, such as live concert streaming or VR teleconferencing.
In einem Studienprojekt „Multimedia CD-ROM RDK - Reallexikon zur Deutschen Kunstgeschichte“ während des Sommersemesters 2002 und des Wintersemesters 2002/03 haben Studierende des Schwerpunktes „Medienerschließung, Information Retrieval“ des Studiengangs Bibliothekswesen den prototypischen Aufbau einer multimedialen, integrierten Nutzungsumgebung für das Reallexikon zur Deutschen Kunstgeschichte realisiert. Die Ergebnisse sowie die zugrunde liegende Vorgehensweise werden in diesem Bericht vorgestellt. Bedingt durch verschiedene Eigenschaften des Originals, das auf höchstem wissenschaftlichen Niveau Zusammenhänge und Fakten in einer Printausgabe ohne bislang hinreichende Zugangsmöglichkeiten (es fehlen bislang Sach- oder Personenregister) anbietet, waren verschiedene Schwierigkeiten zu überwinden, um eine mediengerechte Präsentation der Artikel mit guten Such- und Findemöglichkeiten zu entwickeln. Im Rahmen des Projektes wurden fünf Artikel des Lexikons, die in der Printversion zusammen ca. 60 Seiten umfassen, sowie zusätzliche Informationen in eine Datenbankumgebung eingebracht, die aus sechs einzelnen, teilweise miteinander verknüpften Datenbanken besteht. Grundlage hierfür war die Software MIDOS 2000. Für die Datenbank wurde anschließend eine adäquate Suchumgebung gestaltet. Dem Benutzer wird dort eine zielgenaue Recherche ermöglicht, und die vernetzte Navigationsstruktur bietet die Gelegenheit, komfortablen Zugang zu den Inhalten des Reallexikons und den zusätzlichen Informationen zu erhalten. Ergänzt wird der Projektbericht um je einen Beitrag von PD Dr. Wolfgang Augustyn zum Reallexikon zur Deutschen Kunstgeschichte und von Bernd Ginzkey zum Funktionsumfang der Software MIDOS. Die Betreuer des Projektes sehen es als besonderen Erfolg des Projektes, dass es Vorarbeit zu einem inzwischen bewilligten DFG-Projekt zur Erstellung einer Web-Version des RDK war.
An Analytical Investigation of Natural Convection of a Van Der Waals Gas over a Vertical Plate
(2021)
The study focused on a theoretical study of natural convection in a van der Waals gasnear a vertical plate. A novel simplified form of the van der Waals equation derived in the studyenabled analytical modeling of fluid flow and heat transfer. Analytical solutions were obtained forthe velocity and temperature profiles, as well as the Nusselt numbers. It was revealed that nonlineareffects considered by the van der Waals equation of state contribute to acceleration or decelerationof the flow. This caused respective enhancement or deterioration of heat transfer. Results for a vander Waals gas were compared with respective computations using an ideal gas model. Limits of theapplicability of the simplified van der Waals equations were pinpointed.
The paper focuses on a study of turbulence decay in flow with streamwise gradient. For the first time, an analytical solution of this problem was obtained based on the k‐ε model of turbulence in one‐dimensional (1D) approximation, as well as on the symmetry properties of the system of differential equations. Lie group technique enabled reducing the problem to a linear differential equation. The analytical solution enabled parametric studies, which are computationally cheap in comparison to CFD based simulations. The lattice Boltzmann method (LBM) in two‐dimensional approximation (2D) was used to validate the analytical results. Large eddy simulation (LES) Smagorinsky approach was used to close the LBM model. Computations revealed that the rate of turbulence decay is significantly different for the cases of positive and negative streamwise pressure gradient. The further comparisons showed that the analytical solution underpredicts the predictions by the numerical methodology, which can be attributed to the simplified problem statement used to derive the closed‐form analytical solution. Comparisons of calculations with experiments revealed that the theoretical models used in the study underpredict the measurements for flows with a positive pressure gradient. Hence it can be concluded that the LBM technique combined with the LES Smagorinsky model requires the further modification.
The paper focused on an analytical analysis of the main features of heat transfer in incompressible steady-state flow in a microconfusor with account for the second-order slip boundary conditions. The second-order boundary conditions serve as a closure of a system of the continuity, transport, and energy differential equations. As a result, novel solutions were obtained for the velocity and temperature profiles, as well as for the friction coefficient and the Nusselt number. These solutions demonstrated that an increase in the Knudsen number leads to a decrease in the Nusselt number. It was shown that the account for the second-order terms in the boundary conditions noticeably affects the fluid flow characteristics and does not influence on the heat transfer characteristics. It was also revealed that flow slippage effects on heat transfer weaken with an increase in the Prandtl number.