University of Applied Sciences Emden Leer
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509 research outputs found
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Photon-Induced Near-Field Interaction in Ultrafast Low Energy Electron Microscopy
No full textWe report the first observation of optical near-field coupling to an ultrafast wavepacket of free, low-energy electrons. Transient optical near-fields, highly spatially confined around a nanometer-sized Yagi-Uda-antenna are probed in a point-projection-microscope with 30-fs resolution
Large-Area Growth of MoS2/WS2 Heterostructures by a Sequential Atomic Layer Deposition and Spin-Coating Approach
No full textDespite the plethora of intriguing phenomena observed in heterostructure stacks of 2D transition metal dichalcogenide (2D-TMDC) flakes, their application in functional devices is still hampered due to the lack of reliable growth methodologies for large-area heterostructures. Here, a scalable process for obtaining as-grown transition metal di-chalcogenide heterostructures by a combination of atomic layer deposition of monolayer MoS2 and solution-based processing of ultrathin WS2 is presented. Spatially uniform optical and electrical characteristics of the individual TMDC layers and heterostructures are demonstrated down to micrometer length scales using Raman and photoluminescence spectroscopy, and light-beam-induced current measurements. An enhanced photogenerated current is observed for lateral MoS2–MoS2/WS2 heterostructures demonstrating the suitability of this approach for the preparation of functional devices
Identifying User Experience Aspects for Voice User Interfaces with Intensive Users
No full textVoice User Interfaces (VUIs) are becoming increasingly available while users raise, e.g., concerns about privacy issues. User Experience (UX) helps in the design and evaluation of VUIs with focus on the user. Knowledge of the relevant UX aspects for VUIs is needed to understand the user’s point of view when developing
such systems. Known UX aspects are derived, e.g., from graphical user interfaces or expert-driven research. The user’s opinion on UX aspects for VUIs, however, has thus far been missing. Hence, we conducted a qualitative and quantitative user study to determine which aspects users take into account when evaluating
VUIs. We generated a list of 32 UX aspects that intensive users consider for VUIs. These overlap with, but are not limited to, aspects from established literature. For example, while Efficiency and Effectivity are already well known, Simplicity and Politeness are inherent to known VUI UX aspects but are not necessarily focused. Furthermore, Independency and Context-sensitivity are some new UX aspects for VUIs
Evaluation of Project Work in Public Administrations in E-government and Digitization Projects in Germany
No full textParticularly in times of crisis, it is apparent that the digital transformation in Germany has not yet progressed far enough. Public administrations are confronted with legally prescribed obligations to implement e-government and digitization projects in the near future. Project work and the involvement of users in the implementation are increasingly coming into focus. The objective of this paper is to identify the challenges in project work in the context of the implementation of e-government and digitalization projects in public administration. This was done by comparing survey results from 2018 and 2021 and analyzing whether agility can make a decisive contribution to eliminating these challenges. Moreover, it was investigated whether user involvement in implementation is already taking place. This study was conducted for the first time in 2018 and again in 2021 using an online survey. The two samples of the questionnaire study (2018 and 2021) show, that public administrations are increasingly coming into contact with agile methods. Furthermore, challenges were identified that limit improved project work in public administrations and that need to be addressed
Impact of Usage Behaviour on the User Experience of Netflix, Microsoft Powerpoint, Bigbluebutton and Zoom
No full textIn order to be able to meaningfully classify the user experience and thus the popularity of products, UX questionnaires such as the UEQ, SUS or UMUX are frequently used in practice to measure the UX. This makes it possible to specifically evaluate the ratings of pragmatic and hedonic UX factors. However, it is conceivable that, in addition to users’ own perceptions, external factors also have an influence on the evaluation of the UX of products. These include, for example, time or duration of use. It can be assumed that users who rate the UX of a product as good also use this product more frequently and vice versa. Such a consideration of influencing factors is particularly interesting for products that have been used frequently in recent years and thus also during the pandemic. For this reason, Netflix, Microsoft PowerPoint, Zoom and BigBlueButton were selected, which cover the range from primarily hedonic to primarily pragmatic quality. These are examined for their UX ratings as we ll as influencing factors
Knowledge framework for production planning and controlling considering sustainability aspects in smart factories
No full textAs the human population increases, the demand for products rises. Mass production and the use of these products cause different kinds of sustainable impacts, such as consumption of local and global non-renewable resources or different types of emissions during each stage of the product life-cycle (PLC). Through a systematic overview of these sustainable impacts during the production planning and controlling (PPC) process, sustainability impacts can be identified and possibly avoided. Identifying sustainability impacts is enabled through current developments for manufacturing and product systems digitalization. Data, information, and knowledge are available from each phase from the PLC and can be used for operational, as well as tactical and strategic production management processes. Companies exist, which are unprepared for the impending changes caused by digitalization and related applications. They do not know what and when to measure, as well as how measured data can be connected and analyzed to create new information and knowledge to meet management requirements. To contribute to this problem, the paper proposes a knowledge framework for the collection of data from different PLC phases, analysis of such data to create information, and generation and collection of knowledge for PPC processes. The knowledge framework seeks to answer the research question, which data, information, and knowledge from different PLC phases can be used in PPC processes to identify and avoid sustainability impacts. For this approach, existing concepts for digitalization (RAMI4.0) and knowledge management (business intelligence) are combined. Moreover, the paper presents a qualitative example using the knowledge framework and considering the problem statement about the environmental effects of greenhouse gas (GHG) emissions. Other sustainability problem statements can be considered too, such as employees’ working conditions
Actor-Oriented Scalable Domain-Specific Cluster Architecture for Cloud-Applications
No full textNowadays, applications in the cloud are based on a microservice architecture. Depending on the problem to be solved, they tend to grow complex, and the maintenance is more complicated. For this, a scalable domain-specific (application-related) cluster architecture is conceptualized, which should fulfill the requirements of flexibility, scalability and elasticity, cost-effectiveness, and reliability. Each instance within the cluster covers an application domain. It is possible to upload service subdomains dynamically to an application domain at runtime. A subdomain consists of a group of actors (also called a pod). The development of a subdomain can be assigned to a team. A service subdomain can be scaled individually through replication or sharding (within the instance or the cluster). The proposed solution is expected to achieve a better result than a microservice or FaaS architecture. A single instance prototype was already developed, and a demo application was created
Regionalstudien in internationaler Perspektive
No full textEinleitung In der Suchtprävention spielt die Evaluation von Maßnahmen eine immer größere Rolle (Bühler et al. 2020; de Bock et al. 2020; Institut Suchtprävention 2019), der Anteil anwendungsbezogener Anteile im Studium hat gerade in der Sozialen Arbeit eine große Bedeutung (DG-SAS 2016; Krebs et al. 2021; Laging 2020). Lokale Schülerstudien bieten im Vergleich zu bundesweiten Studien die Chance die begrenzten Mittel der Suchtprävention zielgerichtet auf die passenden Settings, Themen und Zielgruppen auszurichten. Zudem lassen sich durch eine regelmäßige Durchführung Erfolge und Bedarfe der Suchtprävention ableiten. Für die Durchführung regionaler Studien im Anspruch einer gelungenen Präventionsarbeit ist zudem eine gute Netzwerkarbeit unerlässlich. Gerade die Kooperation von Hochschulen und Beratungsstellen bietet hier Chancen.
Material und Methodik International steigt das Interesse an Regionalstudien zur Suchtprävention. Prof. Knut Tielking gibt einen Überblick in die Studienlage in den USA und Australien und ordnet die Delmenhorster Schülerstudie in diesen Kontext ein.
Ergebnisse Regionalstudien bieten die Möglichkeit einer Vergleichbarkeit von Vorrausetzungen und Maßnahmen auf internationaler Ebene mit einem spezifischerem als dem nationalen Fokus. Die regionalen Unterschiede in einzelnen Ländern können was das Konsumverhalten betrifft deutlich sein. Ebenso die Angebote der Suchtprävention. Der Vergleich verschiedener Regionen über Ländergrenzen weg kann mehr Gemeinsamkeiten aufzeigen als in den Regionen innerhalb eines Landes.
Zusammenfassung Der Blick auf die Ergebnisse von Regionalstudien ermöglicht es wirksame Präventionsprojekte besser zu identifizieren und für andere Regionen zu adaptieren
Co-simulation-based analysis of the grid capacity for electric vehicles in districts: the case of “Am Ölper Berge” in Lower Saxony
No full textBattery-electric mobility represents the most promising post-fossil mobility approach as the number of electric vehicles (EVs) worldwide has grown exponentially in recent years. However, the increased electricity demand resulting from EVs' charging processes was unknown when planning the electric grid of existing districts and nowadays may cause violations of operational boundaries. This paper presents an open-source co-simulation using MOSAIK 3.0 to analyze the effects and impacts of an increasing EV penetration rate on the low-voltage grid. The co-simulation is applied to the existing residential district “Am Ölper Berge” in Brunswick, Germany. Within multiple scenarios, user-sided measures for cooperative energy generation, storage, and smart charging strategies are applied to enhance the grid's capacity for EVs by improving voltage regulation. The most effective measure enhancing grid capacity is the self-developed grid correction model, which mitigates voltage range violations using the flexibility of the district's battery storage systems. Solely adding user-sided measures does not create synergistic effects for the grid integration of EVs. Instead, the smart charging strategies enable exploiting these synergies leading to a significant increase in grid capacity. The extendable co-simulation, including the energy system models, simulation scenarios, and input data, will be publicly available and can thus be used for further research
Effect of magnetite addition on transcriptional profiles of syntrophic Bacteria and Archaea during anaerobic digestion of propionate in wastewater sludge
No full textAnaerobic digestion (AD) is an important technology for the effective conversion of waste and wastewater to methane. Here, syntrophic bacteria transfer molecular hydrogen (H2), formate, or directly supply electrons (direct interspecies electron transfer, DIET) to the methanogens. Evidence is accumulating that the methanation of short-chain fatty acids can be enhanced by the addition of conductive material to the anaerobic digester, which has often been attributed to the stimulation of DIET. Since little is known about the transcriptional response of a complex AD microbial community to the addition of conductive material, we added magnetite to propionate-fed laboratory-scale reactors that were inoculated with wastewater sludge. Compared to the control reactors, the magnetite-amended reactors showed improved methanation of propionate. A genome-centric metatranscriptomics approach identified the active SCFA-oxidizing bacteria that affiliated with Firmicutes, Desulfobacterota and Cloacimonadota. The transcriptional profiles revealed that the syntrophic bacteria transferred acetate, H2 and formate to acetoclastic and hydrogenotrophic methanogens, whereas transcription of potential determinants for DIET such as conductive pili and outer-membrane cytochromes did not significantly change with magnetite addition. Overall, changes in the transcriptional profiles of syntrophic Bacteria and Archaea in propionate-fed lab-scale reactors amended with magnetite refute a major role of DIET in the studied system