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Water security is a major concern for water-scarce cities that face dynamic water challenges due to limited water supply, climate change and increasing water demand. Framing urban water security is challenging due to the complexity and uncertainties of the definitions and assessment frameworks concerning urban water security. Several studies have assessed water security by granting priority indicators equal weight without considering or adapting to the local conditions. This study develops a new urban water security assessment framework with application to the water-scarce city
of Madaba, Jordan. The study applies the new assessment framework on the study area and measures urban water security using the integrated urban water security index (IUWSI) and the analytic hierarchy process (AHP) as a decision management tool to prioritise and distinguish indicators that affect the four dimensions of urban water security: drinking water, ecosystems, climate change and water-related hazards, and socioeconomic aspects (DECS). The integrated urban water security index (IUWSI) highlights the state of water security and intervention strategies in Madaba. The study reveals that urban water security in Madaba is satisfactory to meet basic needs, with shortcomings in some aspects of the DECS. However, Madaba faces poor security in terms of managing climate- and water-related risks. The IUWSI framework assists with a rational and evidence-based decision-making process, which is important for enhancing water resources management in water-scarce cities.
The paper presents results of the modelling of heat transfer at film boiling of a liquid in a porous medium on a vertical heated wall bordering with the porous medium. Such processes are observed at cooling of high-temperature surfaces of heat pipes, microstructural radiators etc. Heating conditions at the wall were the constant wall temperature or heat flux. The outer boundary of the vapor film was in contact with moving or stationary liquid inside the porous medium. An analytical solution was obtained for the problem of fluid flow and heat transfer using the porous medium model in the Darcy–Brinkman and Darcy–Brinkman–Forchheimer approximation. It was shown that heat transfer at film boiling in a porous medium was less intensive than in the absence of a porous medium (free fluid flow) and further decreased with the decreasing permeability of the porous medium. Significant differences were observed in frames of both models: 20% for small Darcy numbers at Da < 2 for the Darcy–Brinkman model, and 80% for the Darcy–Brinkman–Forchheimer model. In the Darcy–Brinkman model, depending on the interaction conditions at the vapor–liquid interface (no mechanical interaction or stationary fluid), a sharp decrease in heat transfer was observed for the Darcy numbers lower than five. The analytical predictions of heat transfer coefficients qualitatively agreed with the data of Cheng and Verma (Int J Heat Mass Transf 24:1151–1160, 1981) though demonstrated lower values of heat transfer coefficients for the conditions of the constant wall temperature and constant wall heat flux.
This investigation attempts to understand the eco‐hydrology of, and accordingly suggest an option to manage floodwater for agriculture in, the understudied and data‐sparse ephemeral Baraka River Basin within the hyper‐arid region of Sudan. Reference is made to the major feature of the basin, that is, the Toker Delta spate irrigation scheme. A point‐to‐pixel comparison of gridded and ground‐based data sets is performed to enhance the estimates of rainfall. Analysis of remotely sensed land use/cover data is performed. The results show a significant reduction of the grassland and barren areas explained by a significant expansion of the cropland and open shrubland (invasive mesquite trees) areas in the delta. The cotton sown area is highly dependent on the flooded area and the discharge volume in the delta. However, the area of this major crop has declined since the early 1990s in favour of cultivation of more profitable food crops. Expansion of mesquite in the delta is problematic, taking hold under increased floodwater, and can only be manged by clearance to provide crop cultivation area. There is a great potential for floodwater harvesting during the rainfall season (June to September). A total seasonal runoff volume of around 4.6 and 10.8 billion cubic metres is estimated at 90 and 50% probabilities of exceedance (reliabilities), respectively. Rather than leaving the runoff generated from rainfall events to pass to the Red Sea or be consumed by mesquite trees, a location for runoff harvesting structure in a highly suitable area is proposed. Such a structure will support any policy shifts towards planning and managing the basin water resources for use in irrigating the agricultural scheme.
One-step preparation of bilayered films from kraft lignin and cellulose acetate to mimic tree bark
(2020)
This contribution presents the development of a dry-cast method for the one-step preparation of bio-based films from wood polymers that mimic the bilayered structure of tree bark, the natural protective layer of the tree. In a simplified view, natural bark can be considered as the superposition of an external homogeneous and non-porous layer (outer bark) and a porous substructure layer (inner bark). This work is a first step for the future development of bio-based biomimetic wood coatings. The film had a bark-like appearance and its total density, bulk density and porosity were similar to values measured in natural bark. Furthermore, the structural characteristics of the studied film, namely specific surface area (BET) and pore size distribution, as well as the performance of the water adsorption ability were investigated and discussed.
We consider a risk model in discrete time with dividends and capital injections. The goal is to maximise the value of a dividend strategy. We show that the optimal strategy is of barrier type. That is, all capital above a certain threshold is paid as dividend. A second problem adds tax to the dividends but an injection leads to an exemption from tax. We show that the value function fulfils a Bellman equation. As a special case, we consider the case of premia of size one. In this case we show that the optimal strategy is a two barrier strategy. That is, there is a barrier if a next dividend of size one can be paid without tax and a barrier if the next dividend of size one will be taxed. In both models, we illustrate the findings by de Finetti’s example.
Energiesprong (niederländisch für Energiesprung) ist ein innovatives Konzept für die energetische Sanierung von Wohngebäuden, das schnelle Umsetzung, Kostenreduktion, Nachhaltigkeit und Mieterfreundlichkeit verspricht. Energiesprong setzt auf industrielle Vorfertigung von Fassaden- und Dachelementen (serielle Sanierung) und den Einsatz von regenerativen Energien, um den sogenannten NetZero-Standard (entspricht dem Nullenergiehaus) zu erreichen. Ziel ist es, eine für alle Beteiligten attraktive Sanierung zu ermöglichen. Dies wird unter anderem über erheblich verkürzte Montagezeiten und warmmietenneutrale Refinanzierung angestrebt. Die dafür erforderlichen Kostensenkungen werden beim seriellen Sanieren durch die Automatisierung in der Produktion und Skaleneffekte in der Massenfertigung erreicht.
Im Rahmen dieser Arbeit soll das Konzept Energiesprong hinsichtlich der Anwendung auf Mehrfamilienhäuser betrachtet und kritisch hinterfragt werden. Dazu werden zuvorderst die politischen und praktischen Gründe umrissen, die die Notwendigkeit und das Potenzial von innovativen Ansätzen darstellen. Im zweiten Kapitel wird das Energiesprong-Konzept detailliert erläutert; neben den Innovationen im Plan und Bauverfahren werden die Besonderheiten der Gebäudehülle, der Anlagentechnik und des Energiekonzepts beschrieben. Darüber hinaus werden wirtschaftliche Aspekte und die Rolle der verschiedenen Akteure umrissen. Aus der Beschreibung gehen eine Vielzahl an Vorteilen hervor, die Energiesprong gegenüber konventionellen Sanierungsverfahren verspricht. Anschließend werden einige Punkte dieser zentralen Versprechen diskutiert und eine Grundlage für die Entwicklung von Kriterien zukünftiger Evaluationen entwickelt.
Das vorliegende Paper beschreibt die im Rahmen von Industrie 4.0 als Einkauf 4.0 be-zeichnete Digitalisierung der Einkaufsfunktion. Neben einer grundlegenden Einführung zu Industrie 4.0 und den Haupttreiber stellt das Paper die Auswirkungen der Digitalisie-rung auf den Einkauf vor.
Es werden generell die Möglichkeiten, Einkaufsfunktionen zu digitalisieren, eine Aus-wahl an Studien zu Kosteneinsparungen und der aktuelle Stand der Umsetzung bei Un-ternehmen dargestellt sowie die Erkenntnisse zum Einsatz von Digitalisierung im Ein-kauf zusammengefasst.
Das Praxis Paper basiert auf der Bachelorarbeit von Johannes Blechmann, die von No-vember 2019 bis Februar 2020 von Prof. Dr. Monika Engelen (TH Köln) und Sven Düs-ter (VOSS Automotive GmbH) betreut wurde.
Die Nutzung von Gamification zur Verbesserung der User Experience - Marktanalyse & Designfaktoren
(2020)
User Experience beschreibt die Wahrnehmungen und Reaktionen Benutzender zu einem System. Es umfasst die Gedanken und Emotionen, die Benutzende vor, während und nach der Nutzung eines Systems erfahren. In einer Zeit in der es zahlreiche digitale Systeme und Alternativen auf dem Markt zur Verfügung stehen, können sich voranging Systeme mit einer guten User Experience durchsetzen. Demnach kann User Experience als messbarer Erfolgsfaktor gesehen werden und dieses Verständnis darüber ist erforderlich für das Treffen von Designentscheidungen. Ziel dieser Arbeit ist es Aspekte aus Gamification, die zu einer Verbesserung der User Experience eines Systems beitragen, zu identifizieren und darzustellen. Bei Gamification handelt es sich um einen Gestaltungsprozess, der auf den Erfahrungen und Techniken des Game Designs basiert und die Gefühle und Motivationen von Menschen anspricht. Zur Ermittlung dieser Faktoren wurden mittels Literatur von, unter anderem, Huizinga und Chou relevante Aspekte spielerischen Verhaltens und grundlegende menschliche Motivationen betrachtet. Diese Erkenntnisse wurden zur Analyse der auf, dem Markt befindlichen, Systeme KptnCook und TooGoodToGo angewandt um relevante Design Faktoren zu ermitteln und darzustellen. Es wurde festgestellt, dass User Experience ein dreidimensionales Konstrukt bestehend aus den Faktoren ease-of-use, joy-of-use und purpose-of-use darstellt. Durch die Einbringung von Aspekten aus Gamification in ein System kann dieses gezielt auf die Vermittlung der Faktoren joy-of-use und purpose-of-use gestaltet und optimiert werden. Auf dieser Grundlage ist es empfehlenswert Gamification bei der Gestaltung von Systemen zu beachten um menschlichen Motivationen zur Nutzung eines Systems anzusprechen. Durch die Gestaltung mit Gamification können Benutzererlebnisse angefertigt werden, die unterhaltsam sind und Benutzende zu einer langfristigen Verwendung des Systems motivieren.
Pelleted biomass has a low, uniform moisture content and can be handled and stored cheaply and safely. Pellets can be made of industrial waste, food waste, agricultural residues, energy crops, and virgin lumber. Despite their many desirable attributes, they cannot compete with fossil fuel sources because the process of densifying the biomass and the price of the raw materials make pellet production costly.
Leaves collected from street sweeping are generally discarded in landfills, but they can potentially be valorized as a biofuel if they are pelleted. However, the lignin content in leaves is not high enough to ensure the physical stability of the pellets, so they break easily during storage and transportation. In this study, the use of eucalyptus kraft lignin as an additive in tree-leaf pellet production was studied. Results showed that when 2% lignin is added the abrasion resistance can be increased to an acceptable value. Pellets with added lignin fulfilled all requirements of European standards for certification except for ash content. However, as the raw material has no cost, this method can add value or contribute to financing continued sweeping and is an example of a circular economy scenario.
How Digital Strategy and Management Games Can Facilitate the Practice of Dynamic Decision-Making
(2020)
This paper examines how digital strategy and management games that have been initially designed for entertainment can facilitate the practice of dynamic decision-making. Based on a comparative qualitative analysis of 17 games—organized into categories derived from a conceptual model of decision-making design—this article illustrates two ways in which these games may be useful in supporting the learning of dynamic decision-making in educational practice:
(1) Players must take over the role of a decider and solve situations in which players must pursue different conflicting goals by making a continuous series of decisions on a variety of actions and measures; (2) three of the features of the games are considered to structure players’ practice of decision-making and foster processes of learning through the curation of possible decisions, the offering of lucid feedback and the modification of time. This article also highlights the games’ shortcomings, from an educational perspective, as players’ decisions are restricted by the numbers of choices they can make within the game, and certain choices are rewarded more than others. An educational application of the games must, therefore, entail a critical reflection of players’ limited choices inside a necessarily biased system.
Das vorliegende Praxis Paper ist in zwei Bereiche aufgeteilt. Zunächst wird der Prozess zur Veröffentlichung eines Buchs über Amazon dargestellt, während im zweiten Teil Erkenntnisse über die allgemeinen Grundlagen des erfolgreichen Verkaufs auf Amazon zusammengefasst werden. Es basiert auf der Bachelorarbeit von Herrn Christian Dam-bach, die von Juli 2020 bis Oktober 2020 von Prof. Dr. Monika Engelen betreut wurde.
Nach der Darstellung des Veröffentlichungsprozesses werden im weiteren Verlauf die Möglichkeiten der Suchmaschinenoptimierung auf der Produktseite gezeigt und die Suchmaschinenwerbung über Amazon Marketing Services (AMS) vorgestellt. Neben dem Controlling des Verkaufsverlaufs und des Kampagnenverlaufs, wird zunächst die Einrichtung einer Werbeanzeige erläutert und anschließend die verschiedenen Möglich-keiten der Optimierung dargestellt. Daraus werden dann allgemeine Erfolgsfaktoren für den Verkauf auf Amazon abgeleitet, die, über das Fallbeispiel hinaus, auf jegliche ange-botenen Produkte anwendbar sind.
Die Komplexität der Cybergefahr und die sich entwickelnde Natur des Risikos bringen vielfältige Herausforderungen bei der Gestaltung von Versicherungs-produkten, beim Underwriting, beim Risikomanagement und bei der Kumul-kontrolle mit sich - sowohl für Erst- als auch Rückversicherungsgesellschaften. Eine korrekte Cyberrisikobewertung ist daher unabdingbar und der richtige Ansatz muss stets weiterentwickelt werden. Insbesondere die Vielfältigkeit eines Cyberevents ist hierbei zu berücksichtigen.
In der Cyberversicherung liefert die Vergangenheit keine zuverlässigen Indizien für die Wahrscheinlichkeit eines Schadens; Risiken müssen mit aufwändigen Modellrechnungen simuliert werden. Für die Bewertung von Cyberrisiken könnte die künstliche Intelligenz (KI) von Vorteil sein, um Muster und Wahrscheinlichkeiten im Bereich des Risikotransfers einfacher und effizienter zu analysieren. Einen alternativen Lösungsansatz könnten parametrische Rückversicherungslösungen als Ergänzung zur klassischen Versicherung liefern. So kann eine parametrische Cyberdeckung mit einem definierten Trigger (z.B. mit Hilfe der DSGVO als Trigger) als Auslöser für Schadenzahlungen angeboten werden.
Für eine ausreichende Versicherbarkeit von kleinen und mittelständischen Unternehmen, als auch für größere Industrielösungen könnte eine Risk Pooling Facility geschaffen werden, in welcher sich der traditionelle Rückversiche-rungsmarkt zusammen mit den Insurance Linked Securities Markt die Schadenbelastung teilen. Durch Unterstützung der künstlichen Intelligenz und durch parametrische Trigger (z.B. durch die DSGVO) könnten Schadenverläufe effizienter und zielgerichteter erfolgen.
Durch parametrische Cyberdeckungen könnten Transparenzprobleme bei der Schadenabwicklung verhindert und aufwendige Prüfungen der Rückversicherer reduziert werden. Zudem könnte mit Hilfe einer möglichen KI-Strategie die Bewertungen von Cyberrisiken vereinfacht und effizienter gestaltet werden. Parametrische Cyberlösungen können auch für alternatives Kapital interessant sein, denn auch im NatCat-Bereich sind Vehikel mit solchen Trigger-Lösungen verbreitet.
This bachelor thesis addresses the issue of how school resilience can be measured and assessed quantitatively. Schools as social infrastructures have a significant value for society. Yet, on a global scale, they, and therefore the respective community as well, are continuously endangered by a variety of threats such as natural disasters or violence and mental abuse affecting students, parents and school staff. However, these threats differ greatly depending on climatic and geographical conditions as well as on the socio-cultural context of the corresponding community. To strengthen school resilience against potential threats and to ensure education continuity despite the occurrence of these disruptions, a methodology is developed to measure and assess school resilience in conjunction with its specific circumstances. Initially, qualitative and quantitative (composite) indicators are identified and categorised with the help of a Systematic Literature Review and Mayring's Qualitative Content Analysis. These are subsequently developed into a Comprehensive Index for School Resilience (CISR). Building on this, a pre-existing assessment methodology, which uses Likert-Scales arranged in questionnaires to assign quantitative values to the composite indicators, is adapted to operationalise the CISR and by an exemplary application at Europaschule Troisdorf, the methodology is adapted to the socio-cultural conditions in Germany using an expert’s operational and contextual knowledge. The results obtained show that the methodologies and techniques described in current international research can, after an appropriate adaptation, successfully be applied to schools in Germany as well. Nevertheless, by identifying research limitations and errors as well as potential improvements, it is evident that further research and development is needed to provide stakeholders with a decision-making tool to strengthen the resilience of schools in the future, such as an exhaustive supplement to the CISR or the integration of more precise quantification methodologies and techniques.
With Google’s Flutter framework continuing to grow in popularity for companies and developers alike, the need for an understanding of how to utilize the framework in a large-scale context has become more relevant than ever. The purpose of this thesis is to document the crucial steps most development teams using Flutter in a large-scale application will face. Additionally, a fully documented, large-scale reference application was generated so that other developers may use it as an aid when creating their own Flutter projects on a similar scale. Multiple steps were taken to ensure that optimal solutions were chosen for each aspect of the development process. For each of those aspects, a wide range of possible solutions were explored, compared and analysed. Finally, one of the possible solutions was chosen based on a wide range of scientific papers and community-generated sources. Additionally, an interview with an expert in the field was conducted to further validate those decisions. After the application was fully implemented, ten crucial aspects of the development process were identified. Those ten aspects are now explained in detail in this thesis. Ultimately, the knowledge provided by this thesis can act as a map for peers using Flutter in a large-scale context and help them overcome the crossroads they will most likely come to face.
At the case study of the city of Cologne and the neighbouring Rhein‐Erft‐Kreis (a county), selected resilience aspects of critical infrastructure (CI) and cascading effects are analysed concerning major river floods. Using a Geographic Information System, the applicability of the approach is demonstrated using open source software and data, augmented by manual entries. This study demonstrates the feasibility and limitations of analysing lifeline features of interest for disaster risk and emergency management such as roads, bridges and electricity supply. By highlighting interdependencies of emergency services with CI such as roads, cascading effects of interconnected paths are shown. The findings indicate that in an extreme event flood scenario over 2,000 km of roads and eight bridges will be exposed to floods in the area of the rivers Rhine and Erft. This places huge demands on disaster and emergency management institutions and people affected and limits their resiliency.
The Enhancement of standard dense phase carbon dioxide (DPCD) pasteurization by additional mechanical effects wasassessed in this work. These effects were induced during pasteurization by the sudden depressurization in a narrow mini-tube. The high flow velocities, moderate pressures (40–80 bar) and low temperatures (25–45°C) lead to intense degasifica-tion and shear stress. The inactivation of the test microorganismEscherichia coliDH5a(E. coliDH5a) was determinedbefore and after depressurization in the minitube, representing entirely chemical DPCD via dissolved CO2and total inacti-vation comprising the effects of dissolved CO2and mechanical effects, respectively. Compared to conventional DPCDpasteurization, which is mostly attributed to chemical effects, the additional mechanical effects increased the inactivationefficiency considerably.
This article explores the relationship between digital transformation and disaster risk.Vulnerability studies aim at differentiating impacts and losses by using fine-grained information fromdemographic, social, and personal characteristics of humans. With ongoing digital development,these characteristics will transform and result in new traits, which need to be identified andintegrated. Digital transformations will produce new social groups, partly human, semi-human,or non-human—some of which already exist, and some which can be foreseen by extrapolating fromrecent developments in the field of brain wearables, robotics, and software engineering. Thoughinvolved in the process of digital transformation, many researchers and practitioners in the field ofDisaster Risk Reduction or Climate Change Adaptation are not yet aware of the repercussions fordisaster and vulnerability assessments. Emerging vulnerabilities are due to a growing dependency ondigital services and tools in the case of a severe emergency or crisis. This article depicts the differentimplications for future theoretical frameworks when identifying novel semi-human groups and theirvulnerabilities to disaster risks. Findings include assumed changes within common indicators of socialvulnerability, new indicators, a typology of humans, and human interrelations with digital extensionsand two different perspectives on these groups and their dependencies with critical infrastructure.
This paper introduces CAAI, a novel cognitive architecture for artificial intelligence in cyber-physical production systems. The goal of the architecture is to reduce the implementation effort for the usage of artificial intelligence algorithms. The core of the CAAI is a cognitive module that processes the user’s declarative goals, selects suitable models and algorithms, and creates a configuration for the execution of a processing pipeline on a big data platform. Constant observation and evaluation against performance criteria assess the performance of pipelines for many and different use cases. Based on these evaluations, the pipelines are automatically adapted if necessary. The modular design with well-defined interfaces enables the reusability and extensibility of pipeline components. A big data platform implements this modular design supported by technologies such as Docker, Kubernetes, and Kafka for virtualization and orchestration of the individual components and their communication. The implementation of the architecture is evaluated using a real-world use case. The prototypic implementation is accessible on GitHub and contains a demonstration.
In this paper we describe traffic sign recognition with neural networks in the frequency domain. Traffic signs exist in all countries to regulate the traffic of vehicles and pedestrians. Each country has its own set of traffic signs that are more or less similar. They consist of a set of abstract forms, symbols, numbers and letters, which are combined into different signs. Automatic traffic sign recognition is important for driver assistance systems and for autonomous driving. Traffic sign recognition is a subtype of image recognition. The traffic signs are usually recorded by a camera and must be recognized in real time, i.e. assigned to a class. We use neural networks for traffic sign recognition. The special feature of our method is that the traffic sign recognition does not take place in the spatial domain but in the frequency domain. This has advantages because it is possible to significantly reduce the number of neurons and thus the computing effort of the neural network compared to a conventional neural network.
As Digital Twins gain more traction and their adoption in industry increases, there is a need to integrate such technology with machine learning features to enhance functionality and enable decision making tasks. This has lead to the emergence of a concept known as Digital Triplet; an enhancement of Digital Twin technology through the addition of an ’intelligent activity layer’. This is a relatively new technology in Industrie 4.0 and research efforts are geared towards exploring its applicability, development and testing of means for implementation and quick adoption. This paper presents the design and implementation of a Digital Triplet for a three-floor elevator system. It demonstrates the integration of a machine learning (ML) object detection model and the system Digital Twin. This was done to introduce an additional security feature that enabled the system to make a decision, based on objects detected and take preliminary security measures. The virtual model was designed in Siemens NX and programmed via Total Integrated Automation (TIA) portal software. The corresponding physical model was fabricated and controlled using a Programmable Logic Controller (PLC) S7 1200. A control program was developed to mimic the general operations of a typical elevator system used in a commercial building setting. Communication, between the physical and virtual models, was enabled using the OPC-Unified Architecture (OPC-UA) protocol. Object recognition using “You only look once” (YOLOV3) based machine learning algorithm was incorporated. The Digital Triplet’s functionality was tested, ensuring the virtual system duplicated actual operations of the physical counterpart through the use of sensor data. Performance testing was done to determine the impact of the ML module on the real-time functionality aspect of the system. Experiment results showed the object recognition contributed an average of 1.083s to an overall signal travel time of 1.338 s.
Wärme‐ und Kältespeicher von Gebäuden beruhen auf verschiedenen Konzepten der Wärmeübertragung. Bei thermischen Hybridspeichern befindet sich das Phasen-wechselmaterial (PCM) makroverkapselt in PCM‐Objekten, die im Speicherbehälter positioniert sind und vom Wärmeträgerfluid umströmt werden. Die experimentellen Untersuchungen widmen sich den Belade‐ und Entladeeigenschaften des in Kugeln makroverkapselten PCM. Es wird gezeigt, dass die spezifische Wärmeübertragungs-leistung eines Hybridspeichers unmittelbar von der Größe der Kugeln als auch von der spezifischen Wärmeleitfähigkeit des PCM abhängt.
Digital competences are describing a set of skills, which are necessary to use digital devices and tools with an adequate degree of self-determination. With the ubiquitous digitization of our lives and our society it is important for every citizen to have digital competences. Therefor, it is necessary to educate those competences in schools. As one cannot assume teachers to have enough digital competences to well educate the children of todays classes, this master thesis tries to find out: How to shape the process of teaching digital competences to adolescents in German schools, focusing on including multiple parties from diverse backgrounds into the process? At first, the current situation of teaching digital competences in German schools is analyzed by means of a literature review. After the identification of the challenges within the German system, international best practices are examined. Therefor, four countries, which have reached high scores in the International Computer and Information Literacy Study are selected. Australia, the Czech Republic, Denmark and the Republic of Korea are compared and possible chances for Germany identified. As the next step, expert interviews with divers parties, which have direct or indirect relation to the German education system, are held. The goal of the interviews is to generate ideas on how to support the education system by external help. At the end of the thesis the recommended approach of Motivating External People is presented. Several measures, such as teaching or mentoring students in a guest lecturer model; providing IT support for the hard- and software of the schools or creating Open Educational Resources as education material for the teachers are presented and possible third parties are named. As it is not possible to support the education system from the outside without education system internal persons, it is presented, what needs to change within the system to get the approach working. Therefor, not a complex and system changing approach is presented, but a combined top-down and bottom-up process to motivate external people to support.
To realize a reliable and cost-effective application of high-temperature superconductive (HTS) equipment at high-voltage (HV) levels, the influence of thermally induced gas bubbles on the dielectric strength of different solid insulating materials in liquid nitrogen (LN2) was investigated. A heatable copper tape electrode arrangement was developed simulating HTS tapes with insulation in between. AC breakdown measurements were performed without and with forced boiling on insulating papers, polypropylene laminated paper (PPLP) and polyimide (PI) films. Under nucleate boiling the influence of bubbles on the dielectric strength of all materials was not significant. However under film boiling the dielectric strength of the insulating papers decreased to a level comparable to their dielectric strength in air, demonstrating the insufficient impregnation of porous materials under film boiling. For PI there was no degradation at all. PPLP retained about 70% of its basic dielectric strength in LN2.
Chagas disease is a parasitic infection endemic to America, caused by the protozoan Trypanosoma cruzi and mainly transmitted to humans by contact with insect species of the Triatominae subfamily (Hemiptera). The disease is known to affect disproportionally rural impoverished human communities where it is known to cause premature death and is considered a social and economic burden. The Mexican government has made important progress into the detection, surveillance, treatment, and prevention of the disease in the last decades, however, Chagas disease has also been reported in areas where it had not been previously reported, and there are still barriers for access to treatment. In the state of San Luis Potosi, the disease is more studied in the east, nevertheless, it has been estimated that the reported cases of the entire state have been underestimated. New approaches to detect Chagas risk areas could help prioritize locations for Chagas disease education and prevention programs, detect cases of the disease in a timely manner, and provide access to the necessary treatments. The objective of this study was to identify risk areas for the transmission of Chagas disease in San Luis Potosí using species distribution modelling to estimate vectors and reservoirs’ distributions. To do this, firstly, important vectors and one reservoir species of T. cruzi were identified by reviewing their reported infection rates in literature and the number of times reported in Mexico. Next, species distribution models were calculated for the chosen vector and reservoir species present in the state. The models were done using the Maxent algorithm. Lastly, the resulting distribution models were combined into a risk map by thresholding the model outputs to produce binary predictions and then performing an overlap spatial analysis. Vector species were found to have suitable areas in 36.08% of the state’s territory while areas suitable for both vectors and reservoir were 7.4% of the state’s total area. While this figure may look small at first glance, the analysis suggests that 30% of the rural population and 52% of the urban population of the state are living in an area suitable for vectors and reservoir and therefore at risk. Species distribution modelling can be a powerful tool for identifying human populations at risk of contracting Chagas disease. In the future, including different species of reservoirs into the analysis could help to discover new risk areas in the state.
Der Einsatz von Gebärden scheitert häufig daran, dass bisher kaum bedarfsgerechte Lernangebote für Eltern mit einem unterstützt kommunizierenden Kind zur Verfügung stehen und das obwohl die digitalen Entwicklungen ein großes Spektrum an medienbasierten Lernarrangements eröffnen. Audiovisuelle Lernvideos könnten hier hilfreich sein, denn sie bieten - ähnlich wie die Gebärdensprachkommunikation - eine simultane Darstellung von auditiven und visuellen Informationen. Des Weiteren sind sie heutzutage in jedem Familienalltag durch mobile Endgeräte präsent und halten für Kinder eine Vielzahl von affektiv-sozialen Erlebnissen bereit, die das Lernen unterstützen.
Enhancing DPCD in Liquid Products by Mechanical Inactivation Effects: Assessment of Feasibility
(2020)
The enhancement of standard dense phase carbon dioxide (DPCD) pasteurization by additional mechanical effects was assessed in this work. These effects were induced during pasteurization by the sudden depressurization in a narrow minitube. The high flow velocities, moderate pressures (40–80 bar) and low temperatures (25–45 °C) lead to intense degasification and shear stress. The inactivation of the test microorganism Escherichia coli DH5α (E. coli DH5α) was determined before and after depressurization in the minitube, representing entirely chemical DPCD via dissolved CO2 and total inactivation comprising the effects of dissolved CO2 and mechanical effects, respectively. Compared to conventional DPCD pasteurization, which is mostly attributed to chemical effects, the additional mechanical effects increased the inactivation efficiency considerably.
Wohnungslosigkeit erweist sich in Deutschland als ein wachsendes soziales Problem. Nicht zuletzt aufgrund der zunehmenden Wohnungsknappheit vor allem in den Ballungszentren stellt dies das aktuelle Hilfesystem vor große Herausforderungen. Die wohnräumliche Exklusion führt für die Betroffenen nicht selten zu gesellschaftlicher bzw. sozialer Exklusion. Dies äußert sich auf verschiedenen Ebenen, beispielsweise durch abwertende oder kriminalisierende Betrachtungsweisen in der medialen Berichterstattung, anderen Formen der Diskriminierung bis hin zu verschiedenen Formen der Gewalt. Würdevoller Wohnraum besitzt eine zentrale Bedeutung als Schutz- und Rückzugsraum sowie als Ort, an dem Autonomie und Identität gelebt werden können. Das in den Menschenrechten verankerte Recht auf Wohnen wird jedoch häufig nur unzureichend oder gar nicht gewährleistet. In dieser Arbeit wird beleuchtet, wie sich die Folgen von Wohnungslosigkeit multidimensional auf die Betreffenden auswirken und welche vielfältigen Bedingungen und Faktoren dies beeinflussen. Die daraus resultierenden Aufgaben für Profession und Disziplin Soziale Arbeit werden in diesem Zusammenhang herausgearbeitet. Es wird diskutiert, inwiefern auch Professions-angehörige durch handlungsleitende Prinzipien zum Teil dazu beitragen, dass das Recht auf Wohnen nur unzureichend gewährleistet wird. Vor diesem Hintergrund wird der ursprünglich aus den USA stammende Housing-First-Ansatz samt seinen Herausforderungen vorgestellt und die Potenziale für die Adressat*innen und nicht zuletzt für die Umsetzung des Rechts auf Wohnen analysiert.
Water risk assessment is becoming an essential part of any decision-making process in the business sector. In the world where freshwater resources are becoming scarcer, water risks are growing and causing high costs to businesses. Therefore, numerous frameworks, guidelines, methodologies, tools, and other approaches were developed during the last century. Various scholars have appeared to give an economic value or price for environment goods in order to understand trade-offs better. Nowadays, the corporate world tends to use different approaches to convert sustainability management data to the financial language of decision-makers. This study explores the possible ways for a company to measure the costs of water related risks. It examines how to convert water risks to financial risks using a Peruvian agricultural company. The results show, that from all today’s available frameworks, guidelines or tools there is no one commonly accepted and recognised as the best for water risk assessment and monetising. It was learned, that available tools could provide just a simple overview of possible water related risks and calculate their costs in a very general way. The work also highlights the importance of regular and appropriate data collection on the company level in order to be able to assess water risk related costs for the business.
This paper presents a life cycle assessment (LCA) of photovoltaic (PV) solar modules whichhave been integrated into electric vehicle applications, also called vehicle integrated photovoltaics(VIPV). The LCA was executed by means of GaBi LCA software with Ecoinvent v2.2 as a backgrounddatabase, with a focus on the global warming potential (GWP). A light utility electric vehicle (LUV)named StreetScooter Work L, with a PV array of 930 Wp, was analyzed for the location of Cologne,Germany. An operation time of 8 years and an average shadowing factor of 30% were assumed.The functional unit of this LCA is 1 kWh of generated PV electricity on-board, for which an emissionfactor of 0.357 kg CO2-eq/kWh was calculated, whereas the average grid emissions would be 0.435 kgCO2-eq/kWh. Hence, charging by PV power hence causes lower emissions than charging an EV bythe grid. The study further shows how changes in the shadowing factor, operation time, and otheraspects affect vehicle’s emissions. The ecological benefit of charging by PV modules as compared togrid charging is negated when the shadowing factor exceeds 40% and hence exceeds emissions of0.435 kg CO2-eq/kWh. However, if the operation time of a vehicle with integrated PV is prolonged to12 years, emissions of the functional unit go down to 0.221 kg CO2-eq/kWh. It is relevant to point outthat the outcomes of the LCA study strongly depend on the location of use of the vehicle, the annualirradiation, and the carbon footprint of the grid on that location.
In den letzten Jahren haben sich weltweit drei Sovereign Catastrophe Risk Pools entwickelt, welche Klimaversicherungen gegen Naturkatastrophen in Schwellen- und Entwicklungsländern anbieten:
• Caribbean Catastrophe Risk Insurance Facility (CCRIF) in der Karibik
• African Risk Capacity (ARC) in Afrika
• Pacific Catastrophe Risk Insurance Company (PCRIC) im pazifischen Raum
Hintergrund für die Entwicklung dieser Pools ist der geringe fiskalpolitische Spielraum in Schwellen- und Entwicklungsländern. So sind Erhöhungen von Steuereinnahmen oder Kapitalallokationen kaum möglich. Außerdem endet eine
Verschuldung am Kapitalmarkt häufig im Schuldenerlass, wodurch eine Refinanzierung gefährdet werden kann. Schließlich bleiben nur noch Spenden und Hilfsgelder als Maßnahme übrig, welche u.a. durch die G7-Staaten, die Weltbank oder die Weltgesundheitsorganisation zur Verfügung gestellt werden können.
Projects in universities challenge the students in terms of organizing the project progress and coordinating team members. In order to cover the content of the courses in more depth and to prepare the students for their future employment the technical university of cologne (Campus Gummersbach) includes various team projects into its curriculum. Procedure models are helpful ways to structure the project tasks and ensure the communication between team members and stakeholders. The course Projectmanagement presents procedure models such as Waterfall Model, V-Model and Scrum that are mostly used in business context and software engineering. An agile procedure model that is not part of the curriculum is called Design Thinking. It is a suitable approach for student projects as it combines the requirement of an open mindset, a creative, experimental working method and an interdisciplinary toolbox. The objective of this thesis is to design a concept for a procedure model that is customized to students' needs. The growing practice of the design thinking method and other agile procedures within the business world, also increases the
importance for students to apply of such models in preperation for professional work. To define the requirements for the recommended procedure model, the first step is to elaborate on the processes and challenges that are currently used in student projects. Then the procedure models Waterfall Model, V-Model and Scrum are presented and evaluated taking into account the students' preferences. Next, Design Thinking is presented structured into three parts: mindset, process and toolbox. The most suitable projects to apply this method are identified in the subsequent analysis. Finally, the most appropriate aspects of the presented procedure models as well as the Design Thinking processes are detected, framed and combined into a new procedure model. The new model is illustrated using a graphical representation and a corresponding explanation. It is clustered into the three fundamental project phases: Planning, Execution and Closure. The Planning phase forms the foundation for a well functioning team and successful project progress. Execution is based on the Design Thinking approach and integrates an iteration-loop formed by the subphases Exploration, Idea Generation, Prototyping, Test and Implementation. The final phase Closure is an incentive for a more creative approach to create final presentations. This model can be developed further and be used for example as a didactic instrument and as a link between the diverse disciplines in interdisciplinary projects across different universities. In this way students learn to apply agile procedures and work in interdisciplinary teams.
Eine gängige Form der Qualitätskontrolle von Quellcode sind Code Reviews. Der Fokus von Code Reviews liegt allerdings oft auf syntaktischer Analyse, wodurch weniger Zeit für eine semantische Überprüfung bleibt und zusätzliche Kosten verursacht werden. Code Reviews lassen sich zwar teilweise durch "Linter" automatisieren, dennoch können sie nur syntaktische Fehlermuster identifizieren, welche vorher definiert wurden. Zudem kann ein Linter nur darauf hinweisen, dass möglicherweise ein Fehler vorliegt, da die Fehler nicht durch logische Inferenz ermittelt werden. Die vorliegende Arbeit prüft, ob ein Deep Learning Modell den regelbasierten Ansatz von Lintern ablösen und die semantische Ebene erschließen kann. Dazu wurde eine Stichprobe von Java Methoden zusammengestellt und im Anschluss mit einem Supervised Learning Ansatz binär klassifiziert. Da die Analyse von Quellcode der Textanalyse stark ähnelt wird ein gängiger Ansatz für Textklassifikation verwendet. Dadurch kann gezeigt werden, dass eine Präzision von 85% bei der Erkennung von Quellcodeproblemen durch Deep Learning möglich ist.
In 2015, the adoption of the 2030 Agenda for Sustainable Development, including the 17 Sustainable Development Goals (SDGs), and the Paris Agreement provided a basis for considerable optimism for the fight against climate change and efforts to promote sustainable development, but their implementation remains an enormous challenge. Finance, in turn, plays a key role in implementation. This thesis thus seeks to provide new insights into the challenge of implementing the Paris Agreement and the 2030 Agenda by examining pertinent financial flows while taking into considering that making use of thematic overlaps between these two agendas can help to leverage synergies, especially if financial flows take adequate account of these overlaps. Since energy plays an essential role in both the goals of the Paris Agreement and the 2030 Agenda (in SDG 7 and beyond it), this thesis focuses on countries’ energy-related national commitments. Against this background, this thesis investigates the question which role energy plays in the Nationally Determined Contributions (NDCs) under the Paris Agreement and to what extent climate finance is considered in the context of the energy system transition. The key finding is that financial flow for renewable energy and energy efficiency improves globally with an unchanged track of non-renewable energy in the post-NDC period.
The 13th Annual Meeting of the Sponsoring Group Reinsurance was held 26 June 2020. Due to COVID-19, the event was held online this year. Some 80 representatives of the (re)insurance companies involved in the Sponsoring Group took part in the meeting, along with guests. Offered for the sixth time as part of the Annual Meeting, the Researchers’ Corner gave the seven academic researchers at the Cologne Research Centre for Reinsurance an opportunity to deliver a presentation on the research project each in which each is involved in 2020.
In three sessions – each featuring 2-3 parallel lectures with posters – 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 by academic staff reflects the dovetailing of Cologne Research Centre with reinsurance practice.
Session 1
a) Manuel Dietmann (M.Sc.): Preventive recovery planning for insurance companies
b) Robert Joniec (M.Sc., FCII, cand. PhD): Capital is fungible, the market is
growing more efficient – But how valid are research results?
c) Jörg Dirks (M.Sc., FCII): Cyber risks in reinsurance – Insurable on a parametric basis through AI?
Session 2
a) Wolfgang Koch (M.Sc., FCII): Trend in sovereign cat pools in emerging and developing economies
b) Fabian Lassen (M.Sc., FCII): Environmental social governance – A look at reinsurers
Session 3
a) Fabian Pütz (M.Sc., PhD): Reinsurance aspects of product recalls in the automobile sector
b) Lihong Wang (M.Sc., FCII): China’s Belt and Road Initiative (BRI) – Its impact
on the global (re)insurance industry
Poster session
a) Fabian Lassen (M.Sc., FCII): Private-public partnership – The solution for the insurability of pandemics?
b) Christian Serries (B.Sc.): Silent Cyber as a challenge for the (re-)
insurance industry
c) Frank Cremer (B.Sc. / FCII): Digital ecosystems – Relevance for reinsurance?
d) Harald Kurtze (B.Sc.): Sharing economy – Impacts for reinsurance?
With the publication series, ‘Proceedings of the Researchers’ Corner’, the Cologne Research Centre for Reinsurance meets the desire for publication of the research results of our scholars together with the accompanying posters and discussions. The titles are reproduced in keeping with the above agenda of the Researchers’ Corner
for the 13th Annual Meeting of the Förderkreis Rückversicherung [Sponsoring Group Reinsurance].
Diese Veröffentlichung basiert auf einem Vortrag an dem Forschungsinstitut für Privatversicherungsrecht (Leitung Univ.-Prof. Dr. Michael Gruber) der Universität Salzburg am 7. Januar 2020. Zunächst erfolgte ein kurzer Überblick über die – aus juristischer Sicht vielleicht interessanten – Rückversicherungsaspekte von Solvency II. Anschließend wurden die Organisation und Durchführung von Schiedsgerichtsverfahren in der Rückversicherung erläutert sowie deren Vereinbarung in Rückversicherungsverträgen. Als ein fiktives Beispiel für Gerichts- und Schiedsgerichtsverfahren wurde die fehlende Vereinbarung des für die Rückversicherungsvertragsbeziehung geltenden Rechts gewählt. An dieser Fragestellung wurden die unterschiedlichen Vorgehensweisen eines Gerichts beziehungsweise eines Schiedsgerichtsverfahrens diskutiert. Insbesondere wären in den beiden Verfahren diametral entgegengesetzte Entscheidungen zu erwarten. Im Hauptteil des Vortrags wurden dann die Hurricane-Ereignisse Harvey, Irma und Maria („HIM“) in 2017 adressiert: Verlauf, Schäden, jeweilige Besonderheiten, unterschiedliche Kommunikation gegenüber Öffentlichkeit und Investoren durch einzelne Rückversicherer, Auswirkungen auf die Dividendenpolitik und vieles andere mehr. Danach wurde anhand der Schadenereignisse in den Folgejahren und der uneinheitlichen Renewals seit 2017 in Erst- und Rückversicherung sowie Retrozession die These plausibilisiert,dass der Rückversicherungszyklus spätestens seit HIM ausgesetzt ist. Zur Abrundung wurden die – ebenfalls uneinheitlichen – jeweiligen Entwicklungen von traditionaler Rückversicherung und dem Alternative Risk Transfer durch Insurance Linked Securities gegenübergestellt. Die Volatilität der Rückversicherungsmärkte wird die Akteure sicherlich auch weiterhin in Atem halten – und dem Beobachter die Möglichkeit zu Analyse und Kommentierung.
Proceedings des Researchers‘ Corner zur 13. Jahrestagung des Förderkreises Rückversicherung 2020
(2020)
Am 26. Juni 2020 fand die 13. Jahrestagung des Förderkreises Rückversicherung
statt. Durch Covid-19 bedingt fand in diesem Jahr die Veranstaltung online statt.
Etwa 80 Repräsentanten der in dem Förderkreis mitwirkenden (Rück-)
Versicherungsunternehmen und Gäste nahmen daran teil. Im Rahmen der
Jahrestagung wurde zum sechsten Mal der Researchers‘ Corner durchgeführt, in
dessen Verlauf die sieben wissenschaftlichen Forscher*innen der Kölner
Forschungsstelle Rückversicherung je einen Vortrag zu dem jeweils bearbeiteten
Forschungsprojekt 2020 hielten.
In drei Sessions – mit je 2-3 parallel Vorträgen mit Poster – 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.
Notrufnummern dienen als einfaches Kommunikationsmittel aller Hilfeersuchen der Bevölkerung in Notfällen. Es ist eine optimale Nutzung der Rettungsinstanzen sicherzustellen. Daher ist es notwendig herauszuarbeiten, inwieweit die Bevölkerung, zur Nutzung der Rufnummer des ärztlichen Bereitschaftsdienstes 116117, sensibilisiert ist. Sie stellt eine Entlastung des Regelrettungsdienstes dar. Um ein Meinungsbild der Bevölkerung hinsichtlich Rufnummernpräferenzen zu erhalten, wird eine Umfrage mit konkreten Beispielen analysiert. Es werden Handlungsempfehlungen genannt, um die Bevölkerung auf den ärztlichen Bereitschaftsdienst aufmerksam zu machen.
Against the background of a worldwide decrease in the number of gauging stations,the estimation of river discharge using spaceborne data is crucial for hydrological research, rivermonitoring, and water resource management. Based on the at-many-stations hydraulic geometry(AMHG) concept, a novel approach is introduced for estimating river discharge using Sentinel-1time series within an automated workflow. By using a novel decile thresholding method, no a prioriknowledge of the AMHG function or proxy is used, as proposed in previous literature. With arelative root mean square error (RRMSE) of 19.5% for the whole period and a RRMSE of 15.8%considering only dry seasons, our method is a significant improvement relative to the optimizedAMHG method, achieving 38.5% and 34.5%, respectively. As the novel approach is embedded intoan automated workflow, it enables a global application for river discharge estimation using solelyremote sensing data. Starting with the mapping of river reaches, which have large differences inriver width overthe year, continuous river width time series are created using high-resolution andweather-independent SAR imaging. It is applied on a 28 km long section of the Mekong River nearVientiane, Laos, for the period from 2015 to 2018.
Das vorliegende Paper fasst die Erkenntnisse zum Einsatz von Influencer Marketing generell und besonders für Startups zusammen.
Es basiert auf der Bachelorarbeit von Herr Bilel Mestiri, der von November 2019 bis Februar 2020 von Prof. Dr. Monika Engelen und Prof. Dr. Christina Werner betreut wurde. Neben einer Recherche der grundlegenden Theorie und den daraus gewonnen Erkenntnissen wurde unter Literaturbezug ein Leitfaden erstellt.
Dieses Paper soll als Einstieg in das Thema Influencer Marketing sowie als Orientierungshilfe für den Einsatz von Influencer Marketing für Startups dienen.
Usage of smart home solutions implies generation, processing, and storage of machine and personal data. Recently made public cases of data breaches and misuse increased peoples’ concerns of data security and decreased the trust in secure data handling and smart home technologies. Hence potential benefits are not exploited. It is therefore necessary to analyse how manufacturers can increase their online trust perception.
Requirements of (potential) customers of web based services for HVAC systems are identified using thematic analysis for 23 conducted interviews using online trust perception literature as basis. Manufacturer independent websites are derived as the most important online touch point for customers with manufacturers and products. Determined content and structure measures for online touch points managed by manufacturers derived to positively influence the manufacturer and manufacturer independent touch points regarding perception of trust. The derived trust concept must be evaluated in the following using the defined evaluation plan.
This thesis analyzes the history and current circumstances women belonging to ethnic minorities find themselves in. It also examines how social work deals with this issue. The situation of Indigenous women in Canada as well as Sinti and Roma women in Germany will serve as an example. Within Germany, there are no comparable Indigenous groups that went through a history similar to that of the Indigenous people of Canada. Thus, within the realms of possibility, it is intended to compare their situation to that of Sinti and Roma women and their communities in Germany. After comparing both groups and their current situation, possible consequences and improvements for the field of social work will be indicated
Proper satellite-based crop monitoring applications at the farm-level often require near-daily imagery at medium to high spatial resolution. The combination of data from different ongoing satellite missions Sentinel 2 (ESA) and Landsat 7/8 (NASA) provides this unprecedented opportunity at a global scale; however, this is rarely implemented because these procedures are data demanding and computationally intensive. This study developed a robust stream processing for the harmonization of Landsat 7, Landsat 8 and Sentinel 2 in the Google Earth Engine cloud platform, connecting the benefit of coherent data structure, built-in functions and computational power in the Google Cloud. The harmonized surface reflectance images were generated for two agricultural schemes in Bekaa (Lebanon) and Ninh Thuan (Vietnam) during 2018–2019. We evaluated the performance of several pre-processing steps needed for the harmonization including the image co-registration,
Bidirectional Reflectance Distribution Functions correction, topographic correction, and band adjustment. We found that the misregistration between Landsat 8 and Sentinel 2 images varied from 10 m in Ninh Thuan (Vietnam) to 32 m in Bekaa (Lebanon), and posed a great impact on the quality of the final harmonized data set if not treated. Analysis of a pair of overlapped L8-S2 images over the Bekaa region showed that, after the harmonization, all band-to-band spatial correlations were greatly improved. Finally, we demonstrated an application of the dense harmonized data set for crop mapping and monitoring. An harmonic (Fourier) analysis was applied to fit the detected unimodal, bimodal and trimodal shapes in the temporal NDVI patterns during one crop year in Ninh Thuan province. The derived phase and amplitude values of the crop cycles were combined with max-NDVI as an R-G-B false composite image. The final image was able to highlight croplands in bright colors (high phase and amplitude), while the non-crop areas were shown with grey/dark (low phase and amplitude). The harmonized data sets (with 30 m spatial resolution) along with the Google Earth Engine scripts used are provided for public use.
The use of nematic liquid crystal (LC) mixtures for microwave frequency applicationspresents a fundamental drawback: many of these mixtures have not been properly characterizedat these frequencies, and researchers do not have an a priori clear idea of which behavior they canexpect. This work is focused on developing a new procedure for the extraction of the main parametersof a nematic liquid crystal: dielectric permittivity and loss tangent at 11 GHz under differentpolarization voltages; splay elastic constantK11, which allows calculation of the threshold voltage(Vth); and rotational viscosityγ11, which allows calculating the response time of any arbitrary device.These properties will be calculated by using a resonator-based method, which is implementedwith a new topology of substrate integrated transmission line. The LC molecules should be rotated(polarized) by applying an electric field in order to extract the characteristic parameters; thus,the transmission line needs to have two conductors and low electric losses in order to preserve theintegrity of the measurements. This method was applied to a well-known liquid crystal mixture(GT3-23002 from MERCK) obtaining the permittivity and loss tangent versus bias voltage curves,the splay elastic constant, and the rotational viscosity of the mixture. The results validate the viabilityof the proposed method.
Die Bundesregierung hat sich verpflichtet, die Treibhausgasemissionen in den nächsten Jahren stark zu senken. Potentiale hierfür werden besonders im Gebäudesektor gesehen, da dieser einen hohen Anteil des Endenergieverbrauchs verursacht. Bisher lagen für den Gebäudetypus der „Theaterspielstätte“ im Gegensatz zu anderen Gebäudetypologien weder energetische Kennwerte noch Daten zum Raumkomfort vor. Im Rahmen einer deutschlandweiten Querschnittserhebung in 13 Theaterspielstätten über den Zeitraum von drei Wochen wurden sowohl Energieverbräuche mittels zerstörungsfrei
installierter Messsensoren als auch Daten zum Raumkomfort durch den Einsatz eines Messtorsos auf Nutzerebene sowie
einer parallelen Nutzerbefragung erfasst, ausgewertet und analysiert. Anhand dieser Daten wurden charakteristische Kennwerte gebildet und ein Benchmarking erstellt. Darüber hinaus konnte der Energieverbrauch mittels TEK-Tool rechnerisch auf Nutzungszonen und Gewerke verteilt werden, sodass ein Verständnis für die Struktur des Energieverbrauchs in Theaterspielstätten entwickelt wurde, auf Basis dessen die Abschätzung energetischer Einsparpotentiale möglich ist.
Außerdem wurde durch ein einjähriges Intensivmonitoring im sanierten Scharoun Theater Wolfsburg exemplarisch das Einsparpotential durch Gebäudesanierungen und Anlagenoptimierungen von Theaterspielstätten messtechnisch erforscht. Die gemessenen Daten wurden dem Energieverbrauch vor der Sanierung sowie den Sanierungszielen gegenübergestellt und ebenso gegenüber den Kennwerten aus der Querschnittserhebung eingeordnet.
Die Erkenntnisse über die Nutzungs- und Energieverbrauchsstruktur in Theaterspielstätten können zukünftig angewendet werden, um Energieverbräuche rechnerisch besser ermitteln zu können und um Ansatzpunkte zur Reduzierung des Energieverbrauchs zu identifizieren.
Wetlands offer different ecosystem services that contribute to human well-being (Kovács et al., 2015). According to the Ramsar Convention Secretariat (2018) wetland located in urban areas have been threatened by several activities such as drainage, pollution, encroachment, agriculture, among others. On the other hand, wetland degradation reduces the resilience of hazards like floods and storm surges (Kumar et al., 2017). For that reason, ecosystem-based disaster risk reduction (Eco-DRR) is an important strategy which enhances the conservation and restoration of ecosystems to reduce disaster risk aiming to sustainable development and resilience (Estrella & Saalismaa, 2013). Despite international recognition of the importance of wetlands, urban wetlands have diminished their capacity to cope with flood threats (Boyer and Polasky, 2006) due to the aforementioned human impacts.
That is why this thesis aimed to identify the role of urban wetlands in Bogota, Colombia, that has an urban wetland complex that is recognised as a Ramsar site in 2018. However, wetlands in the city reduced its area from 50.000 hectares to less than 800, approximately, in less than 40 years, mainly because of urban expansion and encroachment (IDIGER, 2018). To achieve this objective, an analysis of the city’s risk management framework was conducted, as well as a stakeholder analysis based on semi-structured interviews and a spatial-temporal analysis for the period 1998-2017, for which the Jaboque wetland was used as a case study. This wetland is located near the Bogotá River and is in the area threatened by flooding.
It was possible to determine that national and district policies on wetlands, biodiversity, and climate change adaptation address some ecosystem functions. Still, disaster risk reduction is not strongly linked to them. Thus, based on the case study, the wetlands in Bogota have not played a decisive role in flood risk management in the city.
We examine the impact of the existence on an explicit deposit insurance (DI) scheme and its design features on bilateral cross‐border deposits (CBD) in a gravity model setting. We find that both the absolute quality of a country's DI and its relative quality vis‐à‐vis other countries' DI generally affect depositor behavior. However, during systemic banking crises, cross‐border depositors primarily seek countries with the best DI schemes. Similarly, during the 2008–2009 great financial crisis, the emergency actions taken by the governments, which supply and maintain these safe havens, have led to substantial relocations of CBD. (JEL F34, G18)
This research analyzes the effects that eco-labels have on the demand for organic (Bio) and Fairtrade (FT) food products. The thesis also discusses the individual determinants and motivations behind those effects. The analysis builds on data obtained from a self-programmed and self-conducted survey, with a sample of 869 students from different universities of Cologne, Germany. The Bio/FT preference is measured experimentally by randomly assigning individuals to treatment and control groups. The experiment simulates life decisions using actual pictures and prices of four products: packed and processed spaghetti, fresh tomatoes, packed raw meat, and packed orange juice.
The existence, size, and direction of statistically significant eco-label effects were obtained with two sample tests of proportions. The results prove that the FT label has a positive differential effect on consumer’s demand. The presence of the FT label makes the purchase of this juice 9.1% higher than other juices not labeled as FT. This finding confirms the hypothesis that eco-labels have a positive effect on sustainable consumption. A surprising finding is that the presence of the Bio label lowers the purchase of organic pasta and tomatoes 7.7% and 9.4% respectively. This finding is interesting because it suggests that Bio labels are not driving the demand for sustainable tomatoes or pasta for this population. Regional and cheaper alternatives are preferred by consumers in this cases.
The motivations behind consumer choices of different options were thoroughly analyzed. Binomial logistic regressions and qualitative text analysis show that the variance in the intention to consume eco-labeled food is explained mainly by price concerns and attitudes about value for money, but also by the influence of life partners as shopping referents, and the perceived behavioral controls of time and ability to monitor compliance of label standards, thus trust them.
The final remarks support the use of the Fairtrade eco-label as a market-based instrument to guide sustainable food consumption among young adults in this context, and propose changes that could make the Bio label more attractive for the targeted population. The thesis demonstrates which individual factors should be inevitably considered when implementing labeling to foster sustainable consumption. Hence, it is useful for evaluations of public and private certification schemes, and for companies that support sustainable food markets. Projects looking to understand and drive sustainable production and consumption decisions should consider this reading.
Campylobacter spp. are one of the most important food-borne pathogens, which are quite susceptible to environmental or technological stressors compared to other zoonotic bacteria. This might be due to the lack of many stress response mechanisms described in other bacteria. Nevertheless, Campylobacter is able to survive in the environment and food products. Although some aspects of the heat stress response in Campylobacter jejuni are already known, information about the stress response in other Campylobacter species are still scarce. In this study, the stress response of Campylobacter coli and Campylobacter lari to elevated temperatures (46°C) was investigated by survival assays and whole transcriptome analysis. None of the strains survived at 46°C for more than 8 h and approximately 20% of the genes of C. coli RM2228 and C. lari RM2100 were differentially expressed. The transcriptomic profiles showed enhanced gene expression of several chaperones like dnaK, groES, groEL, and clpB in both strains, indicating a general involvement in the heat stress response within the Campylobacter species. However, the pronounced differences in the expression pattern between C. coli and C. lari suggest that stress response mechanisms described for one Campylobacter species might be not necessarily transferable to other Campylobacter species.