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Aim: European cities are facing heighten hydrological risks as a result of climate change at the same time as ecological degradation has reduced the environmental capacity to absorb and regulate such fluctuations. Climate forecasts predict more intense convective rainfall and winter flood events in the Wupper Basin in Germany, against a background trend of reduced mean rainfall during the summer months. On 14 July 2021 intense convective rainfall fell at points across Western Germany and led to flash floods in the Wupper Basin, many sites were inundated and the Wupper and Dhünn rivers rose to new record highs. Green-blue infrastructure offers strategies to reduce the impacts of hazards at the same time as providing a range of co-benefits. A study was undertaken to find which green-blue interventions will be most effective at reducing the impacts of hydrometeorological hazards for a study area in the west of the Wupper basin. Furthermore, as landscape features are highly influential in hydrology, the study sought to establish which sites within the landscape can provide maximum results from green-blue interventions, with a minimum of change to current land uses.
Region: Europe, peri-urban and rural, undulating, low mountainous landscapes
Methods: Literature findings on observed and projected climate data are summarised and long-term rainfall data from the study area is analysed to confirm rainfall trends. A state-of-the-art review is conducted and summarised to form a toolbox of potential interventions. The most recent hazardous hydrometeorological event is analysed to inform the locational priorities of potential interventions. Landscape features that have the most influence on basin hydrology are identified from the literature. These sites are paired with green-blue interventions that are shown to have the highest potential impact on interception, infiltration, runoff and flooding. A series of spatial analyses are carried out to produce maps detailing location and intervention with high potential to reduce the impact of hydrometeorological hazards in the study area. All of the evidence gathered from the literature analysis is combined in an implementation guide for green-blue interventions in the Wupper Basin.
Results: The hazards caused by the hydrometeorological extremes of flooding and drought are addressed or minimised through the green-blue interventions that increase interception and infiltration and reduce runoff and flooding. Priority locations are identified as the riparian zone with slope ≤15%, hilltop, lower slope and toe slope, all locations with a slope ≥30% and areas with a high topographic wetness index (TWI). A series of spatial analyses were carried out and suggestions made including potential locations for retention or detention areas and ponds, sites for revegetation and potential locations for implementation of shelterbelts/hedgerows, buffer strips, conservation tillage or strip tillage, reduced mowing intensity or frequency and biochar additions. An implementation guide is created that provides a summary of the highest potential green-blue interventions and landscape locations, and a description of the mechanisms involved in addressing the hydrometeorological hazards.
Keywords: Green-blue interventions, hydrometeorological hazard reduction, Wupper Basin hydrology
The teaching of civil engineering consists of different didactic approaches, such as lectures, group work or research-based teaching, depending on the respective courses. Currently, the metaverse is gaining importance in teaching and offers the possibility of a new teaching approach for civil engineering and especially for the teaching of courses from the areas of “Digital Design and Construction”. Although the advantages of teaching in the metaverse, such as location and time independence or a higher learning outcome, are mentioned in the literature, there are also challenges that must be considered when teaching in the metaverse. Against this background, this paper examines the implications of using the metaverse as a teaching tool in teaching “Digital Design and Construction”. The impact of teaching BIM in the metaverse is evaluated by (1) a literature review and workshops to evaluate use cases and demands for extended reality (XR) and the metaverse, (2) integrating XR and the metaverse in the courses and valuation by quantitative evaluations and (3) analyzing student papers of the courses and outcomes of a World Café. Due to these steps, this paper presents a novel approach by reflecting the students’ perspective. Furthermore, this paper presents a validated approach for integrating BIM and the metaverse in teaching.
Kategorisierung und Bewertung plattformübergreifender Ansätze für die Auswahl eines Frameworks
(2023)
Die plattformübergreifende Entwicklung ist eine populäre Art der Anwendungsentwicklung, die in der Forschung und Industrie immer weiter an Relevanz gewinnt. Dabei wird eine Codebasis geschrieben, die auf mehreren Betriebssystemen lauffähig ist. Das Ziel dieses Ansatzes ist es unter anderem, die Zeit- und Kosteneffizienz zu optimieren. Es gibt verschiedene Ansätze der plattformübergreifenden Entwicklung. Die einzelnen Frameworks lassen sich wiederum in diese Ansätze einteilen. Durch die steigende Akzeptanz dieser Art der Entwicklung herrscht eine zu große Auswahl an Frameworks, von denen jedes eigene Stärken und Schwächen aufweist. Dies ist ein Problem, da Entwickelnde keine Übersicht und Einordnung der Frameworks für ihre individuellen Bedürfnisse haben. Um diesem Problem entgegen zu wirken, wird in dieser Arbeit ein Verfahren entwickelt, mit dem das passende Framework für die Rahmenbedingungen des jeweiligen Projekts ermittelt werden kann. Dazu werden die Frameworks Kotlin Multiplatform, Flutter, React Native und Vue.js, das zur Umsetzung einer PWA genutzt wird, für eine mobile Anwendung getestet, die auf Android und iOS Geräten laufen soll. Zusätzlich werden 44 Kriterien ermittelt, anhand derer die Frameworks bewertet werden. Mit dem resultierenden Verfahren kann sowohl eine objektive, als auch eine subjektive Auswertung der Frameworks erfolgen, um eine geeignete Auswahl zu treffen.
Porous polymer membranes substantially contribute to an acceleration of sustainability transformation based on the energy efficient separation of liquid and gaseous mixtures. This rapid shift toward sustainable industrial processes leads to an increased demand for specifically tailored membranes. In order to predict membrane performance factors like permeability, selectivity and durability, the membrane formation process by film casting and phase inversion needs to be understood further. In recent years, computational models of the membrane formation process have been studied intensely. Their high spatial and temporal resolution allows a detailed quantitative description of phase inversion phenomena. New experimental techniques complement this development, as they provide quantitative data, e.g., on compositional changes of the polymer solution during membrane formation as well as the kinetic progression of the phase separation process. This state-of-the-art review compiles computational and experimental approaches that characterize the phase inversion process. We discuss how this methodological pluralism is necessary for improving the tailoring of membrane parameters, but that it is unlikely to be the way to the ultimate goal of a complete description of the evolution of the membrane structure from the initial demixing to the final solidification. Alternatively, we formulate an approach that includes a database of standardized and harmonized membrane performance data based on previously publicized data, as well as the application of artificial neural networks as a new powerful tool to link membrane production parameters to membrane performance.
Cyber-Risiken, vor allem in Form von Cyber-Kriegsführung und staatlich unterstützten Angriffen, stellen eine große Herausforderung dar. Im Kontext der Versicherung, sollen solche Risiken über Kriegsklausel ausgeschlossen werden. Derzeit gibt es unterschiedliche Herausforderungen wie fehlende klare rechtliche Regelungen, die Unsicherheiten für Versicherer und Versichert darstellen. Die Interviews mit Branchenvertretern zeigen unterschiedliche Meinungen darüber, wie die Versicherungswirtschaft Cyber-Kriegsrisiken wahrnimmt und damit umgeht. Trotz der sich ständig ändernden Natur dieser Bedrohungen besteht weiterhin Bedarf an Forschung und Datenerfassung, um eine gut durchdachte Versicherungslösung zu entwickeln.
Due to their unpredictable nature and sweeping impacts make cyber risks, including cyber warfare and state-sponsored cyber-attacks, present a considerable challenge to many areas of our daily lives. In today’s connected world, the threat of cyber risk is omnipresent. Cyber warfare and state-sponsored cyber-attacks are of particular concern, as they are initiated or supported by governments or state actors. Often, the purpose of such attacks is to compromise critical infrastructure, government systems, businesses, or citizens’ privacy. The impacts can be devastating. They range from financial losses for businesses to theft of intellectual property, disruptions of public order and threats to national security.
Smartphones und die Nutzung von mobilen Anwendungen gewinnen aufgrund der stetig voranschreitenden Digitalisierung weiter an Relevanz. Im April 2022 lag die Zahl der genutzten mobilen Endgeräte bei knapp 6 Milliarden, wobei die Hersteller Apple
und Google einen Marktanteil von knapp 99 % einnehmen. Um als Entwickler eine möglichst große Zielgruppe anzusprechen, ist es daher wichtig, die eigene Anwendung auf möglichst vielen Plattformen zur Verfugung stellen zu können. Die native Entwicklung ist einer der am meist verbreitetste Entwicklungsansatz für mobile Anwendungen. Dort werden plattformspezifische Tools sowie native Programmiersprachen verwendet. Hierbei ergeben sich allerdings diverse Herausforderungen für Entwickler entlang des gesamten Entwicklungsprozesses. Neben der nativen Entwicklung existiert der Ansatz von Cross-Plattform. Hierbei handelt es sich um einen Sammelbegriff für verschiedene Ansätze, welche das Ziel verfolgen eine Anwendung durch die Nutzung einer einheitlichen Codebasis auf mehreren Plattformen zur Verfugung zu stellen. Einer dieser Unteransätze ist
Backend-Driven UI, worin die gesamte Anwendung innerhalb eines strukturierten Datenformats beschrieben und serverseitig verwaltet wird. Der Client kann diese Daten dann dynamisch anfragen und zur Laufzeit in native UI überführen. Das Konzept von Backend-Driven UI wird bereits durch Unternehmen wie Airbnb oder SiriusXM eingesetzt, ist hier allerdings stark auf anwendungsbezogene Prozesse zugeschnitten. Es bedarf daher eines Backend-Driven UI Frameworks, welches es Entwicklern ermöglichen soll, mobile Anwendungen, ohne anwendungsspezifische Einschränkungen plattformübergreifend zu entwickeln. Im Rahmen dieser Arbeit wurde daher zunächst eine plattformunabhängige und erweiterbare Architektur eines solchen Frameworks entwickelt und in Form eines ersten Prototyps auf ihre Umsetzbarkeit geprüft. Insgesamt stellt der Prototyp eine mögliche Umsetzung von Backend-Driven UI dar und ist in der Lage erste Anwendungsszenarien abzudecken. Es konnten dennoch Bereiche ermittelt werden, welche im Zuge zukünftiger Entwicklung ausgebaut werden können. Dazu zählt unter anderem das Umsetzen von serverseitig bestimmter Anwendungslogik sowie der Umgang mit Unterschieden im plattformspezifischen Funktionsumfang.
Die Forschungsarbeit untersucht den sich verhärtenden Rückversicherungsmarkt und die Relevanz von Captives für Industrieunternehmen. Angesichts von Marktveränderungen wie steigender Inflation, Währungsschwankungen und höheren Schadensbelastungen überdenken Unternehmen ihre Risikomanagementansätze. Captives, insbesondere für mittelständische Unternehmen, gewinnen an Bedeutung. Sie bieten direkten Zugang zum Rückversicherungsmarkt, Unabhängigkeit und flexible Gestaltungsmöglichkeiten. Trotz Vorteilen wie optimierten Deckungsstrukturen und Umgehung von Marktveränderungen existieren Herausforderungen, darunter Kapitalanforderungen und Betriebskosten. Der Trend zu neuen Captives im harten Rückversicherungsmarkt ist nicht eindeutig, aber sie bleiben eine innovative Lösung für das betriebliche Risikomanagement. Traditionelle Rückversicherer bleiben entscheidend für die Branchenstabilität.
Hydroxybenzene, commonly known as phenol, is one of the most important organic commodity chemicals. To produce phenol, the cumene process is the most used process worldwide. A crucial step in this process is the Hock rearrangement, which has a major impact on the overall cumene consumption rate and determines the safety level of the process. The most used catalyst for the cleavage of cumene hydroperoxide (CHP) is sulfuric acid. Besides its strong corrosive property, which increases plant investment costs, it also requires neutralization after the decomposition step to prevent side reactions. In this study, we show that high-temperature-treated Linde Type X (LTX) zeolites exhibit a high activity for the peroxide cleavage step. In addition, the structure–activity relationship responsible for this good performance in the reaction system of the HOCK rearrangement was investigated. XRPD analyses revealed the formation of a new phase after temperature treatment above 900 °C. The Si/Al ratio determined by EDX suggested the formation of extra-framework aluminum, which was confirmed by solid-state NMR analysis. The newly formed extra-framework aluminum was found to be responsible for the high catalytic activity. BET analyses showed that the surface area drops at higher calcination temperatures. This leads to a lower catalytic activity for most known reactions. However, for this study, no decrease in activity has been observed. The newfound material shows extraordinarily high activity as a catalyst in the HOCK cleavage and has the potential to be a heterogeneous alternative to sulfuric acid for this reaction.
This study explores the potential of robust, strongly basic type I ion exchange resins—specifically, Amberlyst® A26 OH and Lewatit® K 6465—as catalysts for the aldol condensation of citral and acetone, yielding pseudoionone. Emphasis is placed on their long-term stability and commendable performance in continuous operational settings. The aldol reaction, which traditionally is carried out using aqueous sodium hydroxide as the catalyst, holds the potential for enhanced sustainability and reduced waste production through the use of basic ion exchange resins in heterogeneous catalysis. Density Functional Theory (DFT) calculations are employed to investigate catalyst deactivation mechanisms. The result of these calculations indicates that the active sites of Amberlyst® A26 OH are cleaved more easily than the active sites of Lewatit® K 6465. However, the experimental data show a gradual decline in catalytic activity for both resins. Batch experiments reveal Amberlyst® A26 OH’s active sites diminishing, while Lewatit® K 6465 maintains relative consistency. This points to distinct deactivation processes for each catalyst. The constant count of basic sites in Lewatit® K 6465 during the reaction suggests additional factors due to its unique polymer structure. This intriguing observation also highlights an exceptional temperature stability for Lewatit® K 6465 compared to Amberlyst® A26 OH, effectively surmounting one of the prominent challenges associated with the utilization of ion exchange resins in catalytic applications.
The demand for explainable and transparent models increases with the continued success of reinforcement learning. In this article, we explore the potential of generating shallow decision trees (DTs) as simple and transparent surrogate models for opaque deep reinforcement learning (DRL) agents. We investigate three algorithms for generating training data for axis-parallel and oblique DTs with the help of DRL agents (“oracles”) and evaluate these methods on classic control problems from OpenAI Gym. The results show that one of our newly developed algorithms, the iterative training, outperforms traditional sampling algorithms, resulting in well-performing DTs that often even surpass the oracle from which they were trained. Even higher dimensional problems can be solved with surprisingly shallow DTs. We discuss the advantages and disadvantages of different sampling methods and insights into the decision-making process made possible by the transparent nature of DTs. Our work contributes to the development of not only powerful but also explainable RL agents and highlights the potential of DTs as a simple and effective alternative to complex DRL models.
In recent years there have been numerous technical innovations such as CGM systems or insulin pumps that have made life easier for people with type 1 diabetes. However, this also means that more and more information is available. The aim of the present study is to find out more about the daily handling of information. The following research question was asked: What information do people with type 1 diabetes use? To answer this research question, a quantitative online survey of people with type 1 diabetes was conducted by Prof. Dr. Matthias Fank at the Technical University of Cologne. The online survey mainly consisted of 25 closed questions, which were asked on a scale from 0 to 10. The responses of 1,025 people who are at least 18 years old were included in the evaluation. The most important information for type 1 diabetics is the "current value". 67.5% have this on Place 1 placed. Current glucose levels are provided by CGM systems used by 94.2% of people with type 1 diabetes. Quarterly visits to the diabetologist are important and provide important information. 30.8% “completely” agree with this statement on a scale from 0 to 10. Only 2.2% of people with type 1 diabetes are satisfied with their current diabetes management apps. There is a desire for a manufacturer-independent app. The strongest agreement with a value of 10 was chosen by almost a quarter (24.6%) of the people with type 1 diabetes. The study provides an insight into diabetes therapy and shows the need for action.
In den letzten Jahren gab es zahlreiche technische Innovationen wie CGM Systeme oder Insulin- pumpen, die das Leben von Menschen mit Typ-1-Diabetes erleichtert haben. Dies führt aber auch dazu, dass immer mehr Informationen zur Verfügung stehen. Das Ziel der vorliegenden Studie ist es, mehr über den täglichen Umgang mit Informationen zu erfahren. Dazu wurde die folgende Forschungsfrage gestellt: Welche Informationen nutzen Menschen mit Typ-1-Diabetes?
Um diese Forschungsfrage zu beantworten, wurde eine quantitative Online-Befragung von Men- schen mit Typ-1-Diabetes von Prof. Dr. Matthias Fank an der Technischen Hochschule Köln durch- geführt. Die Online-Befragung bestand überwiegend aus 25 geschlossenen Fragen, die auf einer Skala von 0 bis 10 gestellt wurden. In die Auswertung gingen die Antworten von 1.025 Personen, die mindestens 18 Jahre alt sind, ein.
Die wichtigste Information für Typ-1-Diabetiker ist der “aktuelle Wert“. Diesen haben 67,5% auf
Platz 1 gesetzt. Der aktuelle Glukosewert wird durch CGM-Systeme bereitgestellt, die von 94,2% der Menschen mit Typ-1-Diabetes genutzt werden. Quartalsbesuche beim Diabetologen sind wichtig und liefern wichtige Informationen. Dieser Aussage stimmen 30,8% auf einer Skala von 0 bis 10 „voll und ganz“ zu.
Nur 2,2% der Menschen mit Typ-1-Diabetes sind mit ihren derzeitigen Apps für die Diabetestherapie zufrieden. Der Wunsch nach einer herstellerunabhängigen App ist vorhanden. Die stärkste Zustim- mung mit einem Wert von 10 haben fast ein Viertel (24,6%) der Menschen mit Typ-1-Diabetes ge- wählt. Die Studie gibt einen Einblick in die Diabetestherapie und zeigt Handlungsbedarf auf.
Abstract
Even though researchers are increasingly acknowledging the dark side of customer participation (i.e., behavioral customer engagement), particularly in professional services with high cognitive demands that cause customer participation stress (i.e., negative psychological state resulting from the customer's overextension by required customer participation efforts), insights on how firms can effectively mitigate customer participation stress remains limited. Building on transactional stress theory, we investigate whether customers can effectively cope with the expected cognitive demands of professional services. Moreover, by introducing an adapted coping construct (i.e., coping support), we examine whether employees can provide coping support to help decrease customer participation stress. The findings of a time‐lagged field study with customers of a large German bank (N = 117) suggest that customer coping before the encounter cannot mitigate the effect of anticipated cognitive demands on customer participation stress. Instead, the results of both the field study and a follow‐up experimental study (N = 218) show that a certain set of employee coping support during service encounters is crucial. While focusing on action coping support is not ideal in situations with high cognitive demands, firms should advise their professional service employees to offer emotional coping support to attenuate the unfavorable effect of cognitive demands on customer participation stress.
The annual yield of bifacial photovoltaic systems is highly dependent on the albedo of the underlying soil. There are currently no published data about the albedo of red soil in western Africa. In this study, the impact of the albedo of red soil in Ghana on the energy yield of bifacial photovoltaic systems is analysed. A bifacial photovoltaic simulation model is created by combining the optical view factor matrix with an electrical output simulation. For an exact simulation, the albedo of red soil at three different locations in Ghana is measured for the first time. The average albedo of every red soil is clearly determined, as well as the measurement span including instrumentation uncertainty; values between 0.175 and 0.335 were measured. Considering these data, a state-of-the-art bifacial photovoltaic system with an average of 19.8% efficient modules in northern Ghana can achieve an annual energy yield of 508.8 kWh/m2 and a bifacial gain of up to 18.3% in comparison with monofacial photovoltaic panels. To summarise, red soil in two out of three locations in Ghana shows higher albedo values than most natural ground surfaces and therefore positively impacts the annual yield of bifacial photovoltaic systems.
Positive Impact of Red Soil on Albedo and the Annual Yield of Bifacial Photovoltaic Systems in Ghana
(2023)
The annual yield of bifacial photovoltaic systems is highly dependent on the albedo of the underlying soil. There are currently no published data about the albedo of red soil in western Africa. In this study, the impact of the albedo of red soil in Ghana on the energy yield of bifacial photovoltaic systems is analysed. A bifacial photovoltaic simulation model is created by combining the optical view factor matrix with an electrical output simulation. For an exact simulation, the albedo of red soil at three different locations in Ghana is measured for the first time. The average albedo of every red soil is clearly determined, as well as the measurement span including instrumentation uncertainty; values between 0.175 and 0.335 were measured. Considering these data, a state-of-the-art bifacial photovoltaic system with an average of 19.8% efficient modules in northern Ghana can achieve an annual energy yield of 508.8 kWh/m2 and a bifacial gain of up to 18.3% in comparison with monofacial photovoltaic panels. To summarise, red soil in two out of three locations in Ghana shows higher albedo values than most natural ground surfaces and therefore positively impacts the annual yield of bifacial photovoltaic systems.
Das Labor für Konstruktionstechnik der Technischen Hochschule Köln beschäftigt sich mit der Mikrodosierung von präzisen Strukturen von Silberleitklebstoff. Hauptsächlich wird bei derartigen Ventilen in berührende und berührungslose Dosierventile unterschieden. Zur Erzeugung dreidimensionaler elektrisch leitfähiger Strukturen können diese Dosierventile an entsprechende Verfahreinheiten adaptiert werden.
Das Projekt „IDiT – INCLUDING.DIGITAL.TWINS. Inklusion durch digitale Medien in der beruflichen Bildung“ erforscht, wie Rehabilitand:innen und Auszubildende digitale Expertise und mediale Kompetenzen erwerben können, die für einen erfolgreichen beruflichen (Wieder-)Einstieg unabdinglich sind. Die Integration medienpädagogischer Kompetenzen in Aus- und Fortbildung Lehrender wird bereits geraume Zeit diskutiert und erforscht (vgl. Jahrbuch Medienpädagogik 9, 2012). Dabei lag der Fokus zunächst auf der allgemeinen, schulischen Bildung, mittlerweile gibt es jedoch auch für die berufliche Ausbildung entsprechende Beiträge (vgl. Krämer et al. 2012). Die Sicht der Lehrenden in der beruflichen Ausbildung und Rehabilitation auf medienpädagogische Kompetenzen und Kompetenzmodelle wird bei theoretischen Überlegungen hierzu jedoch nur selten berücksichtigt. Das Projekt IDiT setzt dort an und arbeitet ein bedarfsorientiertes Konzept zur Vermittlung von medienpädagogischer Kompetenz an Lehrende in der beruflichen Rehabilitation aus. Denn für die Vermittlung medialer Kompetenzen braucht es medienkompetente und medienpädagogisch kompetente Lehrende. Doch diese Kompetenzen, in der Form in der sie heute relevant sind1, waren meist kein Bestandteil der professionellen Ausbildung von Lehrpersonen der beruflichen Ausbildung und Rehabilitation.
Die hier vorgeführte Studie erhebt, welche Bedarfe Lehrende in der Berufsausbildung und beruflichen Rehabilitation haben, um digitale Expertise und mediale Kompetenzen an Auszubildende und RehabilitandInnen vermitteln, fördern und stärken zu können.
Für den erfolgreichen Ausbau der Elektromobilität nimmt die Nutzerakzeptanz eine entscheidende Rolle ein. Neben den Anschaffungskosten, Wirkungsgraden und Reichweiten fällt vor allem der Komfort des Ladevorgangs als entscheidende Einflussgröße ins Gewicht. Zum aktuellen Zeitpunkt beeinflussen eine Reihe an negativen Faktoren (z.B. Ladeinfrastruktur, Preisintransparenz und vielfältige Bezahlsysteme) den Ladekomfort und halten potenzielle Käufer eines Elektroautos letztlich vom Erwerb ab. Im Rahmen dieser Arbeit soll aus unmittelbarer Sicht der Nutzer:innen der derzeitige Stand der Ladeinfrastruktur und das aktuelle Nutzerverhalten sowie potenzielle Erfolgsfaktoren herausgearbeitet werden. Weiterhin werden verschiedene Lösungsvorschläge erprobt, die den Ladekomfort an öffentlichen Ladesäulen erhöhen soll. Dazu wird eine zweitstufige Online-Studie im Zuge des vom Bundesministerium für Wirtschaft und Klimaschutz geförderten Transformationsnetzwerk „TrendAuto2030plus“ koordiniert und von Studierenden des Master-Kurses „Technologie und Innovationsmanagement“ an der TH Köln durchgeführt. Gemessen an der bisherigen Nachfrage ist die Ladeinfrastruktur in Deutschland besser als ihr Ruf. Ein deutliches Bild der Unzufriedenheit zeigt sich derweil in Bezug auf die aktuell vorherrschende Preisintransparenz an öffentlichen Ladestationen. Die Vielfalt der Tarifmodelle und Bezahlsysteme erfordern eine großen Strukturierungs- und Informationsbedarf. Es werden Systeme der Preisanzeige gefragt sein, die der Vielfalt und Dynamik der unterschiedlichen Bezahl- und Tarifmodelle Rechnung tragen und diese transparent und nutzerfreundlich ausweisen.
Steer-by-wire systems represent a key technology for highly automated and autonomous driving. In this context, robust steering control is a fundamental precondition for automated vehicle lateral control. However, there is a need for improvement due to degrees of freedom, signal delays, and nonlinear characteristics of the plant which are unconsidered in the design models for the design of current steering controls. To be able to design an extremely robust steering control, suitable optimal models of a steer-by-wire system are required. Therefore, this paper presents an innovative nonlinear detail model of a steer-by-wire system. The detail model represents all characteristics of a real steer-by-wire system. In the context of a dominance analysis of the detail model, all dominant characteristics of a steer-by-wire system, including parameter dependencies, are identified. Through model reduction, a reduced model of the steer-by-wire system is then developed that can be used for a subsequent robust control design. Furthermore, this paper compares the steer-by-wire system with a conventional electromechanical power steering and shows similarities as well as differences.
Das Forschungsprojekt dieses Jahres betont die Verbindung von Theorie und Praxis bei der Analyse der Interaktionen von Marktteilnehmern im Rückversicherungsmarkt. Im Fokus stehen mathematische/aktuarielle Ansätze, insbesondere im Kontext "Optimaler Rückversicherungsverträge". Die Schwierigkeit besteht darin, Erkenntnisse in den Marktalltag zu übertragen. Market Design wird als Schlüssel betrachtet, um greifbare Erkenntnisse zu generieren. Der Bericht stellt Fragen zur Motivation der Marktteilnehmer, den Zielen und Strategien. Eine empirische Befragung der Spieler könnte Einblicke in deren Entscheidungsprozesse liefern. Die Dynamiken im Markt, insbesondere im Hinblick auf Erneuerungszyklen und Retrozessionen, werden ebenfalls diskutiert. Schließlich betont der Bericht die Bedeutung von guten Spielregeln, um asymmetrische Informationen zu minimieren und das kollektive Nutzen von Markt und Gesellschaft zu fördern.
Learning more about the ways in which market participants in the reinsurance market interact based on the logic of a game requires a realisation that the main research that exists is in the mathematical/actuarial direction in which mathematicians deal with ‘optimal reinsurance contracts’. In this connection, negotiations between cedants and reinsurers are viewed in different ways, but always as a strategic game.
Die Reihe „Basiswissen zur Nachhaltigkeit“ versucht zu verschiedenen Themen der Nachhaltigkeit, z.B. Klimawandel, Abfallwirtschaft, soziale Gerechtigkeit, grundlegende Fakten zusammenzustellen. Zielsetzung ist es ein Grundwissen bereitzustellen, das zum einen als Ausgangspunkt für vertiefende Analysen dient und zudem eine faktenbasierte Grundlage für die eigene Meinungsbildung sein kann.
Der vorliegende Aufsatz behandelt die Problemfelder der Abfallwirtschaft in Deutschland und weltweit. Zunächst werden die grundlegenden Informationen zu den Begriffen Abfallwirtschaft, Abfallarten, Abfallentsorgung, Recycling u.a. zusammengetragen. Es folgt eine Darstellung der aktuellen Situtation der deutschen Abfallwirtschaft unter den Aspekten Deponieraum, Müllverbrennung, Recycling, Mikroplastik, Abfallexporte und nukleare Entsorgung. Den Abschluss bildet die Analyse von weltweiten Abfallproblematiken wie unzureichende Sammlung und Deponierung, Verschmutzung der Weltmeere mit Plastikabfall, Belastung der Ozeane durch die Folgen der Weltkriege und der Globalisierung.
Die Reihe „Basiswissen zur Nachhaltigkeit“ versucht zu verschiedenen Themen der Nachhaltigkeit, z.B. Klimawandel, Abfallproblematik, soziale Gerechtigkeit, grundlegende Fakten zusammenzustellen. Zielsetzung ist es ein Grundwissen bereitzustellen, das zum einen als Ausgangspunkt für vertiefende Analysen dient und zudem eine faktenbasierte Grundlage für die eigene Meinungsbildung sein kann. Der vorliegende Aufsatz behandelt die Messung, Ursachen und Folgen des Klimawandels sowie die nationalen und internationalen Strategien und Instrumente zur Lösung der Klimaproblematik. Zunächst werden die grundlegenden Informationen zu den Begriffen Klima, Klimawandel und Klimasysteme dargestellt. Dabei wird insbesondere die Messung und Bewertung von langfristigen Temperaturveränderungen kritisch beleuchtet. Nach einem Überblick über die natürlichen und menschengemachten Ursachen des Klimawandels werden die weltweiten Temperaturziele und daraus abgeleiteten CO2-Restbudgets dargestellt und hinsichtlich ihrer Realisierbarkeit analysiert. Der letzte Teil behandelt die Strategien und Instrumente zur Bewältigung des Klimawandels weltweit und in Deutschland.
This work is intended to make it easier for companies to increase their dynamic capabilities in agile market environments. For this purpose, the areas of a company that are relevant for dynamic capabili-ties are presented and weighted in a clear model. In addition, a direction is proposed for the expansion of dynamic capabilities regarding the order in which the areas of a company should be considered.
The work is based on a literature analysis that provides an approach to bring together the various re-search approaches. For this purpose, the state of research on the topic of dynamic capabilities was developed using an extensive methodology and related to the value chain model according to Porter and the St. Gallen management model, two models valued in practice, in order to identify the relevant areas for dynamic capabilities. The research relates to a broad publication period and a large number of papers. In this way, the various development steps of Dynamic Capabilities over the years could be presented by means of a systematic analysis in which different approaches are summarized. Further-more, these areas were compared and evaluated in terms of relevance in three analysis steps. The findings of the analysis of many individual approaches were summarized in a new model and consider the entire corporate function.
Dieser Beitrag fasst den bisherigen Entwicklungsstand der Dynamic Capabilitiy Forschung systematisch zusammen und schafft ein Konzept zur Übertragbarkeit der Forschungsergebnisse in die praktische Anwendung. Es werden die für die dynamischen Fähigkeiten relevanten Bereiche eines Unternehmens in einem übersichtlichen Modell dargestellt und gewichtet. Darüber hinaus wird eine Richtung für den Ausbau der dynamischen Fähigkeiten vorgeschlagen, in welcher Reihenfolge die Bereiche eines Unternehmens berücksichtigt werden sollten.
Die Arbeit basiert auf einer systematischen Literaturanalyse, die einen Ansatz bietet, die verschiede-nen Forschungsansätze zusammenzuführen. Es wurden die Forschungsergebnisse zu Dynamic Cap-abilities mit dem Wertschöpfungskettenmodell nach Porter und dem St. Galler Managementmodell, zwei in der Praxis etablierte Ansätze, verknüpft, um die relevanten Handlungsfelder für Dynamic Cap-abilities zu identifizieren. Die Untersuchung bezieht sich auf einen breiten Publikationszeitraum und eine große Anzahl relevanter Veröffentlichungen. Durch die übergeordnete Betrachtungsanalyse wird der Beitrag den vielfältigen Forschungsströmungen zu Dynamic Capabilities gerecht. Auf dieser Basis wurde ein funktionaler Gestaltungsansatz für die Praxis entwickelt.
Start-ups operate in dynamic seed stage, start-up stage and growth stage in an uncertain and volatile environment. An analysis of 59 start-ups shows that companies have special characteristics in terms of the organisational characteristics of employer attractiveness and flexible work organisation. The effects of the two organisational characteristics on an agile workforce are proven by a literature study. The study concludes with a theoretical-conceptual model that illustrates the factors influencing employer attractiveness and flexible work organisation. The results of the survey are brought together with the current state of literature and an approach to organisational agility is developed that takes deregulation tendencies into account.
Due to its location at the south-west coast of Ireland County (Co.) Cork is frequently affected by post tropical cyclones (PTCs). There have been several records of these post hurricanes in the past with the last severe PTC being Hurricane Ophelia in 2017. It caused severe disruption in the whole country, especially in Co. Cork with several thousand people without water, power and mobile service for up to 10 days and thousands of uprooted trees which blocked roads. PTCs, like Ophelia, will become more frequent under climate change conditions due to warmer sea surface temperatures and decreased vertical wind shear. Hence, hurricanes can reach northern latitudes more easily and have a higher chance of making landfall in Co. Cork. This thesis assesses the risk perception towards natural hazards (NHs) and the perception of the risk communication of hurricane Ophelia by the citizens of Co. Cork and suggests improvements in communication based on the people’s perception. This was achieved by conducting a standardised survey to analyse the perception. The risk communication chain, its content and media involved were evaluated with interviews with professionals involved in risk management in Ireland. Improvement suggestions were extracted of the survey and the expert interviews as well and have been ranked by the participating experts according to their importance. The people of Co. Cork are not overly concerned about being affected by NHs. The three hazards they feel threatened by most, after Ophelia hit the country, are storms, river floodings and hurricanes. Before Ophelia made landfall, they only ranked hurricanes in the 8th place (out of 8). Ergo, after experiencing Ophelia people are much more aware of hurricane risk in Ireland. People were very satisfied with the information they received during Ophelia. The improvements they wished for are: 1) information on how to deal with and how to prepare for impacts of the storm, 2) the impacts that can be expected locally and 3) information where to go to in case of severe impact to property. These are mostly in line with the improvements the experts ranked as most important for Cork. Experts voted the suggestion to include information on behavioural advice into risk communication before the NH hits and advice on how to organise for impacts afterwards as their number one priority. Their second rank is to have education and training for the citizens in Cork. On third place they voted for a change to impact forecasting. Even there are no central buildings or shelters available in Co. Cork, this improvement suggestion was only voted on rank 13 by the experts (out of 14). Having a participatory approach in risk communication can overcome the discrepancies between the wishes of the population and the ones of the experts and would lead to a better understanding of all stakeholders involved in risk communication and can reduce vulnerability of the people in Co. Cork to the impacts of NHs. The implementation of these activities would be in line with best practice examples and would support the guidelines of the Irish Framework for Major Emergency Management.
Das vorliegende Praxis Paper fasst die gewonnenen Erkenntnisse zum sinnvollen Einsatz von Chatbots im Marketing und deren Einsatzmöglichkeiten für Unternehmen zusammen.
Diese Ausarbeitung basiert auf der Bachelorarbeit von Herrn Andreas Matern, welcher von Juli 2022 bis Oktober 2022 von Frau Prof. Dr. Monika Engelen betreut wurde. Das Ziel der Bachelorarbeit war es, den sinnvollen Einsatz von Chatbots im Marketing herauszuarbeiten. Hierzu wurden elf Chatbot-Agenturen mittels qualitativer Inhaltsanalyse nach Mayring untersucht. Darüber hinaus wurden mögliche Anwendungsbeispiele anhand von vier Fallstudien entlang der Customer Journey analysiert.
The 16th Annual Meeting of the Sponsoring Group Reinsurance [Förderkreis Rückversicherung] was held 16 June 2023 in Niederkassel, near Cologne. Some 90 representatives of the (re)insurance companies involved in the Sponsoring Group
took part in the meeting, along with guests. Offered for the ninth time as part of the Annual Meeting, the Researchers’ Corner gave the six academic researchers at the Cologne Research Centre for Reinsurance an opportunity to deliver a presentation on the research project in which each is involved in 2023. Over the course of three sessions, the most important results of the scientific studies by the Cologne Research Centre for Reinsurance were presented and discussed.
The heterogeneity of the topics presented reflects the dovetailing of Cologne Research Centre with reinsurance practice.
Proceedings des Researchers‘ Corner zur 16. Jahrestagung des Förderkreises Rückversicherung 2023
(2023)
Am 16. Juni 2023 fand die 16. Jahrestagung des Förderkreises Rückversicherung in Niederkassel bei Köln statt. Etwa 84 Repräsentanten der in dem Förderkreis mitwirkenden (Rück-) Versicherungsunternehmen und Gäste nahmen daran teil. Im Rahmen der Jahrestagung wurde zum neunten 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 2023 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.
Multifocal intraocular lenses incorporate a variety of design considerations, including dimensioning of the base monofocal shape and the diffraction grating. While studying three different lens models, we present a practical approach for mathematical modelling and evaluation of these geometries. Contrary to typical lens measurement methods, non-contact measurements were performed on the Alcon SN6AD1, HumanOptics MS 612 DAY and the AMO ZMA00 lenses using a confocal microscope. Subsequent data processing includes centering, tilting correction, filtering and an algorithmic decomposition into a conic and polynomial part and the diffraction grating. Lastly, evaluation of fitting parameters and grating shape is done to allow for inferences about further optical properties. Results and analysis show the confocal microscope to be a suitable imaging method for lens measurements. The processing of this data enables the reconstruction of the annular diffraction grating over the complete lens diameter. Apodization, near addition and diffraction efficiency characteristics are found utilizing the grating shape. Additionally, near-optical axis curvature, asphericity and higher order polynomials are identified qualitatively from the reconstruction of the monofocal base form. Derived properties also include the lens optical base and addition power. By making use of the surface geometries, as well as the lens’ material and thickness, a full lens model can be created for further studies. In summary, our analytical approach enables the insight to various intraocular lens design decisions. Furthermore, this procedure is suitable for lens model creation for research and simulation.
As the population ages, the demand for care for older adults is increasing. To maintain their independence and autonomy, even with declining health, assistive technologies such as connected medical devices or social robots can be useful. In previous work, we introduced a novel health monitoring system that combines commercially available products with apps designed specifically for older adults. The system is intended for the long-term collection of subjective and objective health data. In this work, we present an exploratory user experience (UX) and usability study we conducted with older adults as the target group of the system and with younger expert users who tested our msystem. All participants interacted with a social robot conducting a health assessment and tested sensing devices and an app for data visualization. The UX and usability of the individual components of the system were rated highly in questionnaires in all sessions. All participants also said they would use such a system in their everyday lives, demonstrating the potential of these systems for self-managing users’ health. Finally, we found factors such as previous experience with social robots and technological expertise to have an influence on the reported UX of the users.
Austria is committed to the net-zero climate goal along with the European Union. This requires all sectors to be decarbonized. Hereby, hydrogen plays a vital role as stated in the national hydrogen strategy. A report commissioned by the Austrian government predicts a minimum hydrogen demand of 16 TWh per year in Austria in 2040. Besides hydrogen imports, domestic production can ensure supply. Hence, this study analyses the levelized cost of hydrogen for an off-grid production plant including a proton exchange membrane electrolyzer, wind power and solar photovoltaics in Austria. In the first step, the capacity factors of the renewable electricity sources are determined by conducting a geographic information system analysis. Secondly, the levelized cost of electricity for wind power and solarphotovoltaics plants in Austria is calculated. Thirdly, the most cost-efficient portfolio of wind power and solar photovoltaics plants is determined using electricity generation profiles with a 10-min granularity. The modelled system variants differ among location, capacity factors of the renewable electricity sources and the full load hours of the electrolyzer. Finally, selected variables are tested for their sensitivities. With the applied model, the hydrogen production cost for decentralized production plants can be calculated for any specific location. The levelized cost of hydrogen estimates range from 3.08 EUR/kg to 13.12 EUR/kg of hydrogen, whereas it was found that the costs are most sensitive to the capacity factors of the renewable electricity sources and the full load hours of the electrolyzer. The novelty of the paper stems from the model applied that calculates the levelized cost of renewable hydrogen in an off-grid hydrogen production system. The model finds a cost-efficient portfolio of directly coupled wind power and solar photovoltaics systems for 80 different variants in an Austria-specific context.
Die Welt der digitalen Kundenkommunikation entwickelt sich schnell. Die Kund:innen erwarten Rund-um-die-Uhr Unterstützung und eine schnelle Bearbeitung der Anfragen. Um dies zu ermöglichen, wer-den oft Chatbots in die Kundenkommunikation integriert.
Das Ziel in der vorliegenden Arbeit ist es zu beantworten, welche Auswirkungen der Einsatz von Chat-bots auf die Kundenzufriedenheit und folglich Kundenloyalität und die Kundenwiederkaufrate haben kann. Um die Forschungsfrage zu beantworten, wurde eine Literaturrecherche und Sekundärdatenanalyse aktueller Bücher, wissenschaftlicher Arbeiten, Studien und Forschungen durchgeführt.
Die qualitative Analyse der Ergebnisse der Literaturrecherche und Sekundärdatenanalyse zeigte, dass der Einsatz von Chatbots eine positive Auswirkung auf die Loyalität und das Wiederkaufpotenzial von Kund:innen haben kann und das Kundenerlebnis dadurch verbessert werden kann.
Das vorliegende Praxis Paper fasst Erkenntnisse zum sinnvollen Einsatz von Chatbots zur Steigerung der Kundenzufriedenheit zusammen und leitet Handlungsempfehlungen ab. Diese Ausarbeitung basiert auf der Bachelorarbeit von Frau Tatiana Radchenkova, welche von März 2023 bis Juli 2023 von Frau Prof. Dr. Monika Engelen betreut wurde.
The Production of Isophorone
(2023)
Isophorone is a technically important compound used as a high-boiling-point solvent for coatings, adhesives, etc., and it is used as a starting material for various valuable compounds, including isophorone diisocyanate, a precursor for polyurethanes. For over 80 years, isophorone has been synthesized via base-catalyzed self-condensation of acetone. This reaction has a complex reaction mechanism with numerous possible reaction steps including the formation of isophorone, triacetone dialcohol, and ketonic resins. This review provides an overview of the different production processes of isophorone in liquid- and vapor-phase and reviews the literature-reported selectivity toward isophorone achieved using different reaction parameters and catalysts.
The European heating sector is currently heavily dominated by fossil fuels. Composting is a naturally occurring process in which heat is liberated from the composting substrate at a higher rate than the process needs to support itself. This difference could be harnessed for low-heat applications such as residential consumption, alleviating some of the impacts fossil fuel emissions represent. In this study, the composting heat recovery reported in the literature was compared to the energy demand for space and water heating in four European countries. A review of potential heat production from the waste representative of the residential sector was performed. We found that the theoretically recoverable composting heat does not significantly reduce the need for district heating. However, it can significantly reduce the energy demand for water heating, being able to supply countries such as Greece with between 36% and 100% of the yearly hot water demand, or 12% to 53% of the yearly hot water of countries such as Switzerland, depending on the efficiency of heat recovery.
Ground tire rubber (GTR) is a product obtained by grinding worn tire treads before retreading them or via the cryogenic or ambient temperature milling of end-of-life tires (ELTs). The aim of this study is to evaluate if calcium carbonate can be substituted by GTR and, if so, to what extent. Different types of ground tire rubber are incorporated in an EPDM (ethylene–propylene–diene–rubber) model compound as partial or complete substitutes of calcium carbonate. The raw compounds and the vulcanizates are characterized to identify the limits. In general, it is apparent that increasing amounts of GTR and larger particles degrade the mechanical properties. The GTR also influences the vulcanization kinetics by reducing the scorch time up to 50% and vulcanization time up to nearly 80%. This is significant for production processes. The compounds with one-third substitution with the smaller-particle-size GTR show mostly similar or even better properties than the reference.
During spaceflight, humans experience a variety of physiological changes due to deviations from familiar earth conditions. Specifically, the lack of gravity is responsible for many effects observed in returning astronauts. These impairments can include structural as well as functional changes of the brain and a decline in cognitive performance. However, the underlying physiological mechanisms remain elusive. Alterations in neuronal activity play a central role in mental disorders and altered neuronal transmission may also lead to diminished human performance in space. Thus, understanding the influence of altered gravity at the cellular and network level is of high importance. Previous electrophysiological experiments using patch clamp techniques and calcium indicators have shown that neuronal activity is influenced by altered gravity. By using multi-electrode array (MEA) technology, we advanced the electrophysiological investigation covering single-cell to network level responses during exposure to decreased (micro-) or increased (hyper-) gravity conditions. We continuously recorded in real-time the spontaneous activity of human induced pluripotent stem cell (hiPSC)-derived neural networks in vitro. The MEA device was integrated into a custom-built environmental chamber to expose the system with neuronal cultures to up to 6 g of hypergravity on the Short-Arm Human Centrifuge at the DLR Cologne, Germany. The flexibility of the experimental hardware set-up facilitated additional MEA electrophysiology experiments under 4.7 s of high-quality microgravity (10–6 to 10–5 g) in the Bremen drop tower, Germany. Hypergravity led to significant changes in activity. During the microgravity phase, the mean action potential frequency across the neural networks was significantly enhanced, whereas different subgroups of neurons showed distinct behaviors, such as increased or decreased firing activity. Our data clearly demonstrate that gravity as an environmental stimulus triggers changes in neuronal activity. Neuronal networks especially reacted to acute changes in mechanical loading (hypergravity) or de-loading (microgravity). The current study clearly shows the gravity-dependent response of neuronal networks endorsing the importance of further investigations of neuronal activity and its adaptive responses to micro- and hypergravity. Our approach provided the basis for the identification of responsible mechanisms and the development of countermeasures with potential implications on manned space missions.
A novel approach to manufacture components with integrated conductor paths involves embedding and sintering an isotropic conductive adhesive (ICA) during fused filament fabrication (FFF). However, the molten plastic is deposited directly onto the adhesive path which causes an inhomogeneous displacement of the uncured ICA. This paper presents a 3D printing strategy to achieve a homogeneous cross-section of the conductor path. The approach involves embedding the ICA into a printed groove and sealing it with a wide extruded plastic strand. Three parameter studies are conducted to obtain a consistent cavity for uniform formation of the ICA path. Specimens made of polylactic acid (PLA) with embedded ICA paths are printed and evaluated. The optimal parameters include a groove printed with a layer height of 0.1 mm, depth of 0.4 mm, and sealed with a PLA strand of 700 µm diameter. This resulted in a conductor path with a homogeneous cross-section, measuring 660 µm ± 22 µm in width (relative standard deviation: 3.3%) and a cross-sectional area of 0.108 mm2 ± 0.008 mm2 (relative standard deviation 7.2%). This is the first study to demonstrate the successful implementation of a printing strategy for embedding conductive traces with a homogeneous cross-sectional area in FFF 3D printing.
Maximising Distribution Grid Utilisation by Optimising E-Car Charging Using Smart Meter Gateway Data
(2023)
The transition towards climate neutrality will result in an increase in electrical vehicles, as well as other electric loads, leading to higher loads on electrical distribution grids. This paper presents an optimisation algorithm that enables the integration of more loads into distribution grid infrastructure using information from smart meters and/or smart meter gateways. To achieve this, a mathematical programming formulation was developed and implemented. The algorithm determines the optimal charging schedule for all electric vehicles connected to the distribution grid, taking into account various criteria to avoid violating physical grid limitations and ensuring non-discriminatory charging of all electric vehicles on the grid while also optimising grid operation. Additionally, the expandability of the infrastructure and fail-safe operation are considered through the decentralisation of all components. Various scenarios are modelled and evaluated in a simulation environment. The results demonstrate that the developed optimisation algorithm allows for higher transformer loads compared to a P(U) control approach, without causing grid overload as observed in scenarios without optimisation or P(U) control.
To date, the establishment of high-titer stable viral packaging cells (VPCs) at large scale for gene therapeutic applications is very time- and cost-intensive. Here we report the establishment of three human suspension 293-F-derived ecotropic MLV-based VPCs. The classic stable transfection of an EGFP-expressing transfer vector resulted in a polyclonal VPC pool that facilitated cultivation in shake flasks of 100 mL volumes and yielded high functional titers of more than 1 × 106 transducing units/mL (TU/mL). When the transfer vector was flanked by transposon terminal inverted repeats (TIRs) and upon co-transfection of a plasmid encoding for the transposase, productivities could be slightly elevated to more than 3 × 106 TU/mL. In contrast and using mRNA encoding for the transposase, as a proof of concept, productivities were drastically improved by more than ten-fold exceeding 5 × 107 TU/mL. In addition, these VPC pools were generated within only 3 weeks. The production volume was successfully scaled up to 500 mL employing a stirred-tank bioreactor (STR). We anticipate that the stable transposition of transfer vectors employing transposase transcripts will be of utility for the future establishment of high-yield VPCs producing pseudotype vector particles with a broader host tropism on a large scale.
To date, the establishment of high-titer stable viral packaging cells (VPCs) at large scale for gene therapeutic applications is very time- and cost-intensive. Here we report the establishment of three human suspension 293-F-derived ecotropic MLV-based VPCs. The classic stable transfection of an EGFP-expressing transfer vector resulted in a polyclonal VPC pool that facilitated cultivation in shake flasks of 100 mL volumes and yielded high functional titers of more than 1 × 106 transducing units/mL (TU/mL). When the transfer vector was flanked by transposon terminal inverted repeats (TIRs) and upon co-transfection of a plasmid encoding for the transposase, productivities could be slightly elevated to more than 3 × 106 TU/mL. In contrast and using mRNA encoding for the transposase, as a proof of concept, productivities were drastically improved by more than ten-fold exceeding 5 × 107 TU/mL. In addition, these VPC pools were generated within only 3 weeks. The production volume was successfully scaled up to 500 mL employing a stirred-tank bioreactor (STR). We anticipate that the stable transposition of transfer vectors employing transposase transcripts will be of utility for the future establishment of high-yield VPCs producing pseudotype vector particles with a broader host tropism on a large scale.
Die Handelsspannungen zwischen den USA und China, die sich seit Anfang 2017 verschärft haben, hatten weitreichende Folgen. Am 6. Juli 2018 verhängten die USA Zölle auf chinesische Waren im Wert von 34 Mrd. USD, was Maßnahmen seitens Chinas nach sich zog. Dieser anhaltende Handelsstreit hat zu wirtschaftlichen Spannungen zwischen den beiden größten Volkswirtschaften der Welt geführt, die sich in der Einführung von Zöllen, Handelsbeschränkungen und geopolitischen Unsicherheiten niederschlagen. Die Auswirkungen dieser Maßnahmen waren in verschiedenen Sektoren spürbar und führten zu Unterbrechungen in den globalen Lieferketten, erhöhten Produktionskosten und Nachfrageschwankungen auf den Märkten. Unternehmen, die in diesem komplexen Handelsumfeld tätig sind, sehen sich nun mit erheblichen Unsicherheiten konfrontiert. Die Automobilindustrie, einschließlich Autos, Autoteile, Stahl und Aluminium, ist besonders betroffen.
The prolonged US-China trade tension, initiated in 2017, has led to significant consequences, impacting global supply chains and causing economic tension between the two largest economies. Particularly affecting the automotive sector, the trade war has influenced motor insurance premiums in China, contributing to a declining trend in non-life insurance growth rates from 2017 to 2021. However, a positive outlook is projected for 2023-2026, indicating potential recovery opportunities. The trade war's short-term impacts on the Chinese motor insurance market include increased costs, low premium growth, and economic challenges. In the long term, transformative changes, including market diversification, innovative products, data-driven pricing, and technology-enabled risk prevention, are expected to shape a dynamic and competitive motor insurance landscape in China, offering growth potential despite initial challenges.
Feasibility Study of Wheel Torque Prediction with a Recurrent Neural Network Using Vehicle Data
(2023)
In this paper, we present a feasibility study on predicting the torque signal of a passenger car with the help of a neural network. In addition, we analyze the possibility of using the proposed model structure for temperature prediction. This was carried out with a neural network, specifically a three-layer long short-term memory (LSTM) network. The data used were real road load data from a Jaguar Land Rover Evoque with a Twinster gearbox from GKN. The torque prediction generated good results with an accuracy of 55% and a root mean squared error (RMSE) of 49 Nm, considering that the data were not generated under laboratory conditions. However, the performance of predicting the temperature signal was not satisfying with a coefficient of determination (R2) score of −1.396 and an RMSE score of 69.4 °C. The prediction of the torque signal with the three-layer LSTM network was successful but the transferability of the network to another signal (temperature) was not proven. The knowledge gained from this investigation can be of importance for the development of virtual sensor technology.
In its Renewables 2022 Report, the International Energy Agency (IEA) projects that the share of renewable energies in the global energy mix will increase from 22.8% in 2015 to 38.1% in 2027. This trend goes hand-in-hand with increasing construction of plants for the generation of renewable energies, leading to increased demand for (re)insurance. Comparable to the development of traditional energy sources, the hedging of current risks is a key element in the further development of renewable energies. According to projections by the IEA, by 2027 most of the energy from renewable sources will be generated using photovoltaics or solar as well as onshore and offshore wind.