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Tobias Meier, Leo Penta und Andreas Richter (Hrsg.) (2022) : Community Organizing. Eine Einführung
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Tobias Meier, Leo Penta und Andreas Richter (Hrsg.) (2022)
Community Organizing. Eine Einführung
ISBN 978-3-7799-6804-7, 310 S., 34
Impact of mixed speed networks on the performance of Ethernet real time communication protocols like PROFINET
Get PDFThe trend towards the use of Ethernet in automation networks is ongoing. Due to its high flexibility, speed, and bandwidth, Ethernet nowadays is not only widely used in homes and offices worldwide but finding its way into industrial applications. Especially in automation processes, where many field devices send data in relative short time spans, the requirements for a safe and fast data transfer are high. This makes the use of industrial Ethernet essential. A new hardware-layer, specifically tailored for industrial applications, has been introduced in the form of Ethernet-APL (‘Advanced Physical Layer’). Ethernet-APL is based on the Ethernet standard and implements a two-wire Ethernet-based communication for field devices and provides data and power over a two-wire cable. The operation in areas with potentially explosive atmosphere is also possible. This enables a modular, fast, and transparent Ethernet network structure throughout the entire plant. However, by integrating Ethernet-APL into the field, industrial networks in the future will face the challenge of operating at varying datarates at different locations in the network, resulting in a ‘mixed link speed’ network. This can lead to limitations in packet-throughput and consequently to potential packet loss of system relevant data, which must be avoided. Therefore, the purpose of this thesis is to investigate the potential of packet loss in ‘mixed link speed’ networks
A Comprehensive Analysis of the Penetration of Detailed Type 4 Wind Turbine Generators in the Two-Area Benchmark System
Get PDFThe shift towards RES introduces challenges related to power system stability due to the characteristics of inverter-based resources (IBRs) and the intermittent nature of renewable resources. This paper addresses these challenges by conducting comprehensive time and frequency simulations on the IEEE two-area benchmark power system with detailed type 4 wind turbine generators (WTGs), including turbines, generators, converters, filters, and controllers. The simulations analyse small-signal and transient stability, considering variations in active and reactive power, short-circuit events, and wind variations. Metrics such as rate of change of frequency (RoCoF), frequency nadir, percentage of frequency variation, and probability density function (PDF) are used to evaluate the system performance. The findings emphasise the importance of including detailed models of RES in stability analyses and demonstrate the impact of RES penetration on power system dynamics. This study contributes to a deeper understanding of RES integration challenges and provides insights for ensuring the reliable and secure operation of power systems in the presence of high levels of RES penetration
Genome-wide interaction analysis of folate for colorectal cancer risk
Get PDFBackground: Epidemiological and experimental evidence suggests that higher folate intake is associated with decreased colorectal cancer (CRC) risk; however, the mechanisms underlying this relationship are not fully understood. Genetic variation that may have a direct or indirect impact on folate metabolism can provide insights into folate’s role in CRC.
Objectives: Our aim was to perform a genome-wide interaction analysis to identify genetic variants that may modify the association of folate on CRC risk.
Methods: We applied traditional case-control logistic regression, joint 3-degree of freedom, and a 2-step weighted hypothesis approach to test the interactions of common variants (allele frequency >1%) across the genome and dietary folate, folic acid supplement use, and total folate in relation to risk of CRC in 30,550 cases and 42,336 controls from 51 studies from 3 genetic consortia (CCFR, CORECT, GECCO).
Results: Inverse associations of dietary, total folate, and folic acid supplement with CRC were found (odds ratio [OR]: 0.93; 95% confidence interval [CI]: 0.90, 0.96; and 0.91; 95% CI: 0.89, 0.94 per quartile higher intake, and 0.82 (95% CI: 0.78, 0.88) for users compared with nonusers, respectively). Interactions (P-interaction < 5×10-8) of folic acid supplement and variants in the 3p25.2 locus (in the region of Synapsin II [SYN2]/tissue inhibitor of metalloproteinase 4 [TIMP4]) were found using traditional interaction analysis, with variant rs150924902 (located upstream to SYN2) showing the strongest interaction. In stratified analyses by rs150924902 genotypes, folate supplementation was associated with decreased CRC risk among those carrying the TT genotype (OR: 0.82; 95% CI: 0.79, 0.86) but increased CRC risk among those carrying the TA genotype (OR: 1.63; 95% CI: 1.29, 2.05), suggesting a qualitative interaction (P-interaction = 1.4×10-8). No interactions were observed for dietary and total folate.
Conclusions: Variation in 3p25.2 locus may modify the association of folate supplement with CRC risk. Experimental studies and studies incorporating other relevant omics data are warranted to validate this finding
Internationalization strategies of multi-product firms: The role of technology
Get PDFHigh-performance firms typically have two features in common: (i) they produce in more than one country and (ii) they produce more than one product. In this paper, we analyze the internationalization strategies of multi-product firms. Guided by several new stylized facts, we develop a theoretical model to determine optimal modes of market access at the firm–product level. We find that the most productive firmssell core varieties via foreign direct investment and export products with intermediate productivity. Shocks to trade costs and technology affect the endogenous decision to export or produce abroad at the product-level and, in turn, the relative productivity between parents and affiliates.Stratégies d’internationalisation des entreprises multiproduits : Le rôle de la technologie. Les entreprises à haut rendement partagent habituellement deux caractéristiques : i) elles produisent dans plus d’un pays et ii) elles produisent plus d’un produit. Dans cet article, nous analysons les stratégies d’internationalisation des entreprises multiproduits. En nous fondant sur plusieurs nouveaux faits stylisés, nous élaborons unmodèle théorique pour déterminer les modes optimaux d’accès au marché au niveau de l’entreprise et du produit. Nous constatons que la plupart des entreprises productives vendent des variétés de base par l’entremise d’investissement direct étranger et exportent des produits avec une productivité intermédiaire. Les chocs aux coûts de commerce et la technologie ont un effet sur la décision endogène d’exporter ou de produire á l’étranger au niveau du produit et, du coup, sur la productivité relative entre les sociétés mères etles sociétés affiliées
FID Civil Engineering, Architecture and Urbanism digital - A platform for science (BAUdigital)
Get PDFUniversity Library Braunschweig (UB Braunschweig), University and State Library Darmstadt (ULB Darmstadt), TIB – Leibniz Information Centre for Technology and Natural Sciences and the Fraunhofer Information Centre for Planning and Building (Fraunhofer IRB) are jointly establishing a specialised information service (FID, "Fachinformationsdienst") for the disciplines of civil engineering, architecture and urbanism. The FID BAUdigital, which is funded by the German Research Foundation (DFG, "Deutsche Forschungsgemeinschaft"), will provide researchers working on digital design, planning and production methods in construction engineering with a joint information, networking and data exchange platform and support them with innovative services for documentation, archiving and publication in their data-based research
Wikidata and Wikibase as complementary research data management services for cultural heritage data
Get PDFThe NFDI (German National Research Data Infrastructure) consortia are associations of various institutions within a specific research field, which work together to develop common data infrastructures, guidelines, best practices and tools that conform to the principles of FAIR data. Within the NFDI, a common question is: What is the potential of Wikidata to be used as an application for science and research? In this paper, we address this question by tracing current research usecases and applications for Wikidata, its relation to standalone Wikibase instances, and how the two can function as complementary services to meet a range of research needs. This paper builds on lessons learned through the development of open data projects and software services within the Open Science Lab at TIB, Hannover, in the context of NFDI4Culture – the consortium including participants across the broad spectrum of the digital libraries, archives, and museums field, and the digital humanities
Mixed-Integer Real-time Control of a Building Energy Supply System
Get PDFWe present a methodology based on mixed-integer nonlinear model predictive control for a real-time building energy management system in application to a single-family house with a combined heat and power (CHP) unit. The developed strategy successfully deals with the switching behavior of the system components as well as minimum admissible operating time constraints by use of a special switch-cost-aware rounding procedure. The quality of the presented solution is evaluated in comparison to the globally optimal dynamic programming method and conventional rule-based control strategy. Based on a real-world scenario, we show that our approach is more than real-time capable while maintaining high correspondence with the globally optimal solution. We achieve an average optimality gap of 2.5% compared to 20% for a conventional control approach, and are faster and more scalable than a dynamic programming approach
Förderung von Informationskompetenz in Spezialbibliotheken unter Berücksichtigung von Wissenskulturen
Get PDFZiel dieser Bachelorarbeit ist es Empfehlungen für eine Neukonzeption zur Förderung von Informationskompetenzen an Spezialbibliotheken mit der Hauptzielgruppe Wissenschaftler*innen am Beispiel der Forschungsbibliothek des Leibniz-Institut für Bildungsmedien | Georg-Eckert-Instituts (GEI) unter Berücksichtigung der Wissenskulturen zu formulieren.
Es wird festgestellt, dass die lebenslange Weiterbildung der Informationskompetenz bei Wissenschaftler*innen unabdingbar ist und im Einklang mit der Steigerung der Forschungsproduktivität steht. Trotz dieser Erkenntnisse gibt es in der Fachliteratur bisher kaum nennenswerte Konzepte zur Förderung der Informationskompetenz der Forschenden in Spezialbibliotheken. Mit Hilfe der wissenskulturellen Analyse, basierend auf den Ansätzen der KIBA-Gruppe zu Informationsdidaktik und der Wissenskulturen von Karin Knorr-Cetina, wird ein Interview-Leitfaden entwickelt, mit Hilfe dessen bei 10 Mitarbeitenden des GEI eine Analyse der Wissenskultur und der Bedürfnisse durchgeführt wird. Die Ergebnisse zeigen, dass für die Förderung von Informationskompetenz ein ganzheitliches Konzept benötigt wird, welches sich nicht nur ausschließlich auf reine Schulungen beschränkt. Es sind verschiedene Formate notwendig, um die individuellen Bedürfnisse der Forschenden abzudecken. Besonders virtuelle Angebote sollen integriert werden. Die Ergebnisse lassen sich allerdings nicht auf andere Spezialbibliotheken deckungsgleich übertragen. Die wissenskulturelle Analyse kann jedoch als Grundlage angewendet werden, um auch in anderen Spezialbibliotheken ein neues Konzept zur Förderung der Informationskompetenz bei Wissenschaftler*innen zu entwickeln
Digitale und hybride Lernraumgestaltung in Wissenschaftlichen Bibliotheken
Get PDFDer digitale Wandel beschäftigt Hochschulen schon länger, doch verhalf die Corona-Pandemie zu einem Aufschwung in der Digitalisierung. Dies bringt Veränderungen in der Hochschullehre mit sich. Auch Hochschulbibliotheken sind für die digitale Bildung von Bedeutung. Es gilt herauszufinden, welche Anforderungen an die Lernraumgestaltung aufgrund der derzeitigen Hochschullehre entstehen. Ziel ist es, nachzuvollziehen, wie der Lernort Wissenschaftliche Bibliothek bei der Nutzung von neuen Technologien und dem Erwerb der dafür benötigten Kompetenzen helfen, und um welche Angebote und Dienstleistungen er ergänzt werden kann. Diese literaturbasierte Theoriearbeit beantwortet die Frage, wie Lernräume in Wissenschaftlichen Bibliotheken digital und hybrid gestaltet werden können, um die heutige Lehre an Hochschulen kompetenzorientiert zu unterstützen. Zentral ist die praxisorientierte Betrachtung von lehr- und lernunterstützenden Diensten wie Makerspaces, Learning Labs sowie Beratung und Schulung. Ein weiterer Schwerpunkt liegt auf dem Einsatz von digitalen und hybriden Elementen im physischen Lernraum wie interaktiven Whiteboards, Multitouch-Tables sowie Augmented und Virtual Reality. Die soziale Interaktion, Kooperationen, Supportstrukturen und die Kompetenzvermittlung bilden eine wichtige Basis. Zur Veranschaulichung von unterstützenden Angeboten für Lernen und Lehren werden Good-Practice-Beispiele herangezogen. Die erarbeitete Vielfalt an Handlungsmöglichkeiten zeigt, wie klassische Lernraumsettings durch organisatorische, didaktische und technische Ausstattungen erweitert, weiterentwickelt und verbessert werden können