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Creating Data-Driven Products and Services in Industry 4.0: A Case Study on Companies in the German Machine and Tool Industry
Full text linkDuring the past ten years, lots of new data-driven products and services for tools, machinery and equipment have been developed. While several new players from other industries gained a certain market share, plant and machinery producers also started to enhance their portfolio to take on new data-driven products and services because of the technological changes in Industry 4.0. As a first part of the research, an extensive market study was carried out to analyze how many German companies already offer data-based products and services in addition to their core machines and understand what kind of offerings they make. To classify these offerings, a scheme based on established Industry 4.0 maturity models was developed. In brief, the market for data-driven products and services is still developing, with few technology leaders and fast movers taking the largest share. While the market study gave an overview of what was on offer, the second part of this contribution analyzes how the fast movers with a high level of Industry 4.0 maturity conducted their data-driven services and products. Thus, these few companies were analyzed in more detail, based on public material as well as subsequent expert interviews. Most fast movers in this study relied on the same patterns and approaches, especially when looking at organizational issues such as customer-driven innovation, agile organization of operations, mixed teams, partnering and portfolio enhancement
Satellite-Based Detection of Algal Blooms in Large Alpine Lake Sevan: Can Satellite Data Overcome the Unavoidable Limitations in Field Observations?
Full text linkLake Sevan in Armenia is a unique, large, alpine lake given its surface, volume, and geographic location. The lake suffered from progressing eutrophication and, since 2018, massive cyanobacterial blooms repeatedly occurred. Although the lake is comparatively intensely monitored, the feasibility to reliably detect the algal bloom events appeared to be limited by the established in situ monitoring, mostly because algal bloom dynamics are far more dynamic than the realized monitoring frequency of monthly samplings. This mismatch of monitoring frequency and ecosystem dynamics is a notorious problem in lakes, where plankton dynamics often work at relatively short time scales. Satellite-based monitoring with higher overpass frequency, e.g., by Sentinel-3 OLCI with its daily overcasts, are expected to fill this gap. The goal of our study was therefore the establishment of a fast detection of algal blooms in Lake Sevan that operates at the time scale of days instead of months. We found that algal bloom detection in Lake Sevan failed, however, when it was only based on chlorophyll due to complications with optical water properties and atmospheric corrections. Instead, we obtained good results when true-color RGB images were analyzed or a specifically designed satellite-based HAB indicator was applied. These methods provide reliable and very fast bloom detection at a scale of days. At the same time, our results indicated that there are still considerable limitations for the use of remote sensing when it comes to a fully quantitative assessment of algal dynamics in Lake Sevan. The observations made so far indicate that algal blooms are a regular feature in Lake Sevan and occur almost always when water temperatures surpass approximately 20 °C. Our satellite-based method effectively allowed for bloom detection at short time scales and identified blooms over several years where classical sampling failed to do so, simply because of the unfortunate timing of sampling dates and blooming phases. The extension of classical in situ sampling by satellite-based methods is therefore a step towards a more reliable, faster, and more cost-effective detection of algal blooms in this valuable lake
The Tortured Journalists Department? Challenges and Characteristics of Quality Journalism on TikTok in Germany
Full text linkOur study investigates how German journalists produce quality journalism on TikTok based on 22 semistructured interviews. Specifically, we explore whether German journalists adhere to established journalistic norms and values, using Lacy & Rosenstiel's quality journalism framework as a theoretical foundation. Given the prominent role of public service media and their legal mandate to contribute to public opinion formation, Germany constitutes an interesting case. Findings suggest that German journalists rely on a mixture of traditional journalistic standards and audience-related news values on TikTok. Moreover, they tailor content to the unique platform environment. This entails the adoption of TikTok-specific storytelling with crisp openers, simplified narrating styles, and appealing audiovisuals. Editorial quality management remains crucial, with public service journalists exhibiting more sophisticated content approval and production processes than private media journalists. Overall, German journalists strike a balance between upholding journalistic integrity and adapting to TikTok's distinctive dynamics
Proceedings des Researchers‘ Corner zur 17. Jahrestagung des Förderkreises Rückversicherung 2024
Full text linkAm 28. Juni 2024 fand die 17. Jahrestagung des Förderkreises Rückversicherung in Niederkassel bei Köln statt. Etwa 90 Repräsentanten der in dem Förderkreis mitwirkenden (Rück-) Versicherungsunternehmen und Gäste nahmen daran teil. Im Rahmen der Jahrestagung wurde zum zehnten Mal der Researchers‘ Corner durchgeführt, in dessen Verlauf die sechs wissenschaftlichen Forscher*innen der Kölner Forschungsstelle Rückversicherung je einen Vortrag zu dem jeweils bearbeiteten Forschungsprojekt 2024 hielten.
In drei Sessions wurden die wichtigsten Ergebnisse der wissenschaftlichen Untersuchungen der Kölner Forschungsstelle Rückversicherung präsentiert und diskutiert. Die Heterogenität der vorgetragenen Themen spiegelt die Verzahnung der Kölner Forschungsstelle mit der Rückversicherungspraxis wider. Darüber hinaus wurde ein externer Vortrag gehalten.
Session 1
a) Frank Cremer (PhD, FCII): Praxis und Forschung zu Risikotransfer von Cyber-Risiken
b) Lihong Wang (M.Sc., FCII): Opportunities and Challenges in the Chinese Electric Vehicle Market: Insights for (Re)insurers
Session 2
a) Jörg Dirks (M.Sc., FCII): Konjunktureller Abschwung durch geopolitische Spannungen – Toprisiko für Rückversicherer
b) Erik Winkler (M.Sc.): War, Terror & Political Violence Event Definitions – Quo Vadis Reinsurance Market?
Session 3
a) Robert Joniec (PhD, FCII): Gruppeninterne Rückversicherung – Über Risikotransfer hinaus
b) Fabian Lassen (M.Sc., FCII): Erdbebengefährdung und deren Versicherung in Österreich
Externer Vortrag
a) Prof. Dr. Ulrich Frischknecht: Steuert Deutschland auf eine Opioidkrise zu?
Mit der Veröffentlichungsreihe „Proceedings des Researchers‘ Corner“ entspricht die Kölner Forschungsstelle Rückversicherung dem Wunsch, die Forschungsergebnisse unserer Forscher*innen sowie die Diskussionen zu publizieren. Dabei werden die Titel gemäß der oben aufgeführten Agenda des Researchers‘ Corner der 17. Jahrestagung des Förderkreises Rückversicherung wiedergegeben
A Comparative Evaluation of Community-Used District and Individual Battery Storage Systems for Photovoltaic Energy Systems
Full text linkThe significant expansion of renewable energies has led to an increased importance of storage systems. Decentralized storage solutions, including Home Battery Energy Storage Systems (HBESSs) and District Battery Energy Storage Systems (DBESSs), play a crucial role in this context. This study compares individual HBESSs with a community-used DBESS regarding the grade of autarky and self-consumption, specifically focusing on a planned residential area consisting of 36 single-family houses. A simulation tool was developed to conduct load flow simulations based on household electricity consumption, wallbox profiles for electric vehicle charging, and photovoltaic generation data across various battery capacities and system boundaries. The results demonstrate that the DBESS, compared to individual HBESSs with equivalent cumulative battery capacities, can achieve a maximum increase in the grade of autarky of up to 11.6%, alongside an 8.0% increase in the grade of self-consumption for the given use case. In terms of capacity, the DBESS allows for a saving of up to 68% compared to HBESS to achieve similar results for the studied neighborhood
Material Characterization of Silicones for Additive Manufacturing
Full text linkThree-dimensional printing is ideally suited to produce unique and complex shapes. In this study, the material properties of polysiloxanes, commonly named silicones, produced additively by two different methods, namely, multi-jet fusion (MJF) and material extrusion (ME) with liquid printing heads, are investigated. The chemical composition was compared via Fourier-transform infrared spectroscopy, evolved gas analysis mass spectrometry, pyrolysis gas chromatography coupled to mass spectrometry, and thermogravimetry (TGA). Density and low-temperature flexibility, mechanical properties and crosslink distance via freezing point depression were measured before and after post-treatment at elevated temperatures. The results show significant differences in the chemical composition, material properties, as well as surface quality of the tested products produced by the two manufacturing routes. Chemical analysis indicates that the investigated MJF materials contain acrylate moieties, possibly isobornyl acrylate linking branches. The hardness of the MJF samples is associated with crosslinking density. In the ashes after TGA, traces of phosphorus were found, which could originate from initiators or catalysts of the curing process. The ME materials contain fillers, most probably silica, that differ in their amount. It is possible that silica also plays a role in the processing to stabilize the extrusion strand. For the harder material, a higher crosslink density was found, which was supported also by the other tested properties. The MJF samples have smooth surfaces, while the ME samples show grooved surface structures typical for the material extrusion process. Post-treatment did not improve the material properties. In the MJF samples, significant color changes were observed
An Alternative Livelihood for a Mining Community in the Sierra Gorda de Querétaro, Mexico. A Sustainability Analysis.
Full text linkThis thesis investigates the sustainability of proposed alternative livelihoods for the mining community of Camargo in the Sierra Gorda of Querétaro, Mexico. With the impending ban on mercury mining under the Minamata Convention, the community faces the urgent need to transition to sustainable livelihoods. Utilizing the Sustainable Livelihoods Framework (SLF) as a guiding theoretical model, this study assesses the current state of the Five Capitals—human, social, natural, physical, and financial—within the community. It also examines the community's perceptions and attitudes toward these alternative livelihoods and evaluates the external influences, such as government and academic institutions, that impact their sustainability.
Data were collected through semi-structured interviews with community members, miners, and external stakeholders, and analyzed using qualitative coding in MAXQDA. The findings reveal a complex interplay between the Capitals of the community and the role that external stakeholders play, highlighting both opportunities and barriers to follow a path of sustainability.
The study concludes that the livelihoods with most potential for a sustainability path are the cultivation of regional species and the installation of a touristic point in the community. A holistic approach that integrates economic, social, and environmental dimensions, while at the same time considers a tailored natural resources management, is essential for ensuring the path of sustainability of the livelihoods. Points of leverage for change are presented for policy and advocacy, infrastructure development of the community, and considering local resource management in the design and implementation of sustainable livelihood strategies
The Effects of High Shear Rates on the Average Hydrodynamic Diameter Measured in Biomimetic HIV Gag Virus-Like Particle Dispersions
Full text linkHIV Gag virus-like particles (HIV Gag VLPs) are promising HIV vaccine candidates. In the literature, they are often described as shear-sensitive particles, and authors usually recommend the operation of tangential flow filtration (TFF) gently at shear rates below 4,000 s −1 to 6,000 s −1 . This in turn poses a severe limitation to the performance of TFF-mediated concentration of VLPs, which would be substantially enhanced by working at higher shear rates. To our knowledge, studies examining the shear sensitivity of HIV Gag VLPs and providing detailed information and evidence for the fragility of these particles have not been conducted yet. Thus, we investigated the effect of high shear rates on the colloidal stability of mosaic VLPs (Mos-VLPs) as relevant examples for HIV Gag VLPs. For this purpose, Mos-VLPs were exposed to different shear rates ranging from 3,395 s −1 to 22, 365 s −1 for 2 h. The average hydrodynamic diameter (AHD) and the polydispersity index (PDI) of the associated particle size distribution were used as stability indicators and measured after the treatment and during storage through dynamic light scattering. At high shear rates, we observed an increase in both AHD and PDI during the storage of HIV Mos1.Gag VLPs (bVLP—without envelope proteins) and Mos1.Gag + Mos2S.Env VLPs (eVLP—with envelope proteins). eVLPs exhibited higher colloidal stability than bVLPs, and we discuss the potential stabilizing role of envelope proteins. We finally demonstrated that the dispersion medium also has a considerable impact on the stability of Mos-VLPs
ChatGPT, schreibe mir einen Aufsatz über Ursula Georgy
Full text linkBeitrag zur Festschrift für Ursula Georg
Assessment of Bioenergy Potential from Biomass Waste to Improve Access to Clean Energy for Cooking in Mali
Full text linkA lack of access to clean cooking fuels and technologies in Mali is causing negative health and welfare impacts on the population. There is a need to transition to cleaner cooking systems, and the production of biofuels is one promising solution. In order to successfully use biofuels in Malian households, it is necessary to calculate the sustainable bioenergy potential of the country. The aim of this study, therefore, was to assess this potential to determine if it can meet the cooking energy demand. Statistical data were used to estimate the bioenergy potential from three different biomass resources: crop residues, livestock waste, and municipal solid waste (MSW). Surveys in urban and rural areas in Mali were performed to assess cooking fuel consumption in the residential sector. Bioenergy potential and cooking energy demand were compared regionally to find out if biomass is a feasible substitute for traditional cooking fuels in Mali. It was shown that while there is high biogas potential in most of the regions, urban Bamako has a lack of biomass resources to cover the demand. Therefore, other clean alternatives like electric cooking should be considered for urban areas