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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.
This thesis is aimed for finding a solution for non-gaming application of Virtual Reality technology in data visualization and analysis. Starting by reconstructing the concept of Virtual Reality, the paper then describes the principles, concepts and techniques of designing a Virtual Reality application. In the last part of the thesis, a detailed description of how a prototype implemented is presented to provide a preview of how data visualization and analysis and Virtual Reality technology can be combined together in order to enable users to perceive and comprehend data in a possibly better way.
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.
The method of operation of auctions and their use in
a variety of economic sectors is already well documented. Auctions are already in use for the Placement of reinsurance on a small scale. So why is it important to revisit
this field, which has already been studied in such considerable detail?
• Two researchers, Paul R. Milgrom and Robert B. Wilson of Stanford University, were honoured with the Nobel Prize in Economics in 2020 for their improvements in auction theory and the invention of new auction formats.
• A trend towards automation is in the Placement of reinsurance is emerging. In this connection, a variety of InsurTechs and market initiatives, such as B3i and
Ritablock, are dealing with various fields of application of blockchain technology.
• The persistent low-interest-rate environment, together with existing competition
and cost pressures from primary insurers, mean that insurers are in search of savings potentials.
• Auctions are proving to be a successful model in many areas of the economy, e.g. in the allocation of frequencies in mobile communication, subsidies for wind farms or energy pricing.
Achieving urban water security is a major challenge for many countries. While several studies have assessed water security at a regional level, many studies have also emphasized the lack of assessment of water security and application of measures to achieve it at the urban level.
Recent studies that have focused on measuring urban water security are not holistic, and there is still no agreed-upon understanding of how to operationalize and identify an assessment framework to measure the current state and dynamics of water security. At present, there is also no clearly defined and widely endorsed definition of urban water security. To address this challenge, this study provides a systematic approach to better understand urban water security, with a working definition and an assessment framework to be applied in peri-urban and urban areas. The proposed working definition of urban water security is based on the United Nations (UN) sustainable development goal on water and sanitation and the human rights on water and sanitation. It captures issues of urban-level technical, environmental, and socio-economic indicators that emphasize credibility, legitimacy, and salience.
The assessment framework depends on four main dimensions to achieve urban water security: Drinking water and human beings, ecosystem, climate change and water-related hazards, and socio-economic factors (DECS). The framework further enables the analysis of relationships and trade-off between urbanization and water security, as well as between DECS indicators. Applying this framework will help governments, policy-makers, and water stakeholders to target scant resources more eff ectively and sustainably. The study reveals that achieving urban water security requires a holistic and integrated approach with collaborative stakeholders to provide a meaningful way to improve understanding and managing urban water security.
Circular economy (CE) has received considerable interest in recent years as a strategy to resolve some of our modern urban resource challenges, and circular city models often incorporate systems of urban agriculture in their design. Much work has analyzed the benefits of urban agriculture for creating a resilient food system and as a strategy for supporting urban green space and social cohesion, however, the contributions from business models that operate within urban agriculture have not been thoroughly studied. Many urban agriculture businesses often claim high levels of resource recycling and material circularity, though whether a resource efficiency throughout the entire product lifetime (including energy and material footprint for the cultivation equipment) in comparison to current industrial strategies is truly feasible or even possible is still to be debated. This thesis builds upon work that incorporates social dimensions of CE definitions and begins to research whether the potential resource efficiency contradiction can be justified as to make urban agriculture a valid approach for circular city design. This study examined an urban mushroom farm that implements a circular business model. A qualitative summary of the business operations and resource flows were unpacked and sorted into 24 socio-economic contributions based on their interpreted relevance. The interpreted data shows that an urban agriculture business model can contribute to the building blocks of a CE through economic, ecological, social, and spatial contributions. While these contributions can contribute positively to the operationalization of CE, potential trade-offs regarding resource efficiency, use of urban space, and investment priorities need to be considered and addressed to avoid a possible watering down or greenwashing of the CE concept.
In recent years, three sovereign catastrophe risk pools have developed worldwide, offering climate insurance against natural disasters in emerging and developing economies:
• Caribbean Catastrophe Risk Insurance Facility (CCRIF) in the Caribbean
• African Risk Capacity (ARC) in Africa
• Pacific Catastrophe Risk Insurance Company (PCRIC) in the Pacific region
These pools have emerged against the backdrop of limited fiscal room for manoeuvre in emerging and developing economies. Increases in tax revenues or capital allocations are scarcely possible in these economies. Moreover, debt on the capital market often ends in debt relief, and this can jeopardise refinancing. Ultimately, the only measure remaining is to provide donations and aid that can be made available by the G7 countries, the World Bank or the World Health Organization, among others.
Stable recombinant mammalian cells are of growing importance in pharmaceutical biotechnology production scenarios for biologics such as monoclonal antibodies, growth and blood factors, cytokines and subunit vaccines. However, the establishment of recombinant producer cells using classical stable transfection of plasmid DNA is hampered by low stable gene transfer efficiencies. Consequently, subsequent selection of transgenic cells and the screening of clonal cell populations are time- and thus cost-intensive. To overcome these limitations, expression cassettes were embedded into transposon-derived donor vectors. Upon the co-transfection with transposase-encoding constructs, elevated vector copy numbers stably integrated into the genomes of the host cells are readily achieved facilitating under stringent selection pressure the establishment of cell pools characterized by sustained and high-yield recombinant protein production. Here, we discuss some aspects of transposon vector technologies, which render these vectors promising candidates for their further utilization in the production of biologics.
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.
Despite intensive research over the last three decades, it has not yet been possible to bring an effective vaccine against human immunodeficiency virus (HIV) and the resulting acquired immunodeficiency syndrome (AIDS) to market. Virus-like particles (VLP) are a promising approach for efficient and effective vaccination and could play an important role in the fight against HIV. For example, HEK293 (human embryo kidney) cells can be used to produce virus-like particles. In this context, given the quality-by-design (QbD) concept for manufacturing, a digital twin is of great importance for the production of HIV-Gag-formed VLPs. In this work, a dynamic metabolic model for the production of HIV-Gag VLPs was developed and validated. The model can represent the VLP production as well as the consumption or formation of all important substrates and metabolites. Thus, in combination with already described process analytical technology (PAT) methods, the final step towards the implementation of a digital twin for process development and design, as well as process automation, was completed.
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.
Abstract
Due to their pronounced bioactivity and limited availability from natural resources, metabolites of the soft coral Pseudopterogorgia elisabethae, such as erogorgiaene and the pseudopterosines, represent important target molecules for chemical synthesis. We have now developed a particularly short and efficient route towards these marine diterpenes exploiting an operationally convenient enantioselective cobalt‐catalyzed hydrovinylation as the chirogenic step. Other noteworthy C−C bond forming transformations include diastereoselective Lewis acid‐mediated cyclizations, a Suzuki coupling and a carbonyl ene reaction. Starting from 4‐methyl‐styrene the anti‐tubercular agent (+)‐erogorgiaene (>98 % ee) was prepared in only 7 steps with 46 % overall yield. In addition, the synthesis of the pseudopterosin A aglycone was achieved in 12 steps with 30 % overall yield and, surprisingly, was found to exhibit a similar anti‐inflammatory activity (inhibition of LPS‐induced NF‐κB activation) as a natural mixture of pseudopterosins A−D or iso‐pseudopterosin A, prepared by β‐D‐xylosylation of the synthetic aglycone.
Aerobic microbial cultivations are industrially important group of processes and pose challenges for the reactor design. In particular, estimation of industrial scale conditions is difficult from laboratory and pilot scale data. Due to complex interaction of gas/liquid phase hydrodynamics, mass transfer parameters and microbial metabolism, both improvement of modelling tools and reactor design are desired. We present an approach to estimate growth conditions in industrial scale reactor by combining black-box metabolic models with CFD-model.
The reactor type used here is Outotec OKTOP9000®, which is used in the industrial hydrometallurgical processes at 900 m3 scale. It is adopted to a laboratory setting and compared to stirred tank reactor (STR) in gas dispersion, mass transfer and yeast cultivation experiments. In addition, a kinetic model for the yeast growth is developed based on literature sources and validated by the laboratory scale batch cultivations. This kinetic model is used along with CFD-model that is developed to describe the flow and mass transfer conditions in the industrial scale reactor.
The laboratory scale experiments show the feasibility of OKTOP9000® reactor when compared to STR, particularly with improved gas handling capacity. The modelling approach shows qualitatively similar behavior in the large scale simulations when compared to laboratory scale cultivations.
Thioredoxin (Trx) overexpression is known to be a cause of chemotherapy resistance in various tumor entities. However, Trx effects on resistance are complex and depend strictly on tissue type. In the present study, we analyzed the impact of the Trx system on intrinsic chemoresistance of human glioblastoma multiforme (GBM) cells to cytostatic drugs. Resistance of GBM cell lines and primary cells to drugs and signaling inhibitors was assessed by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assays. Impact of Trx inhibition on apoptosis was investigated by proteome profiling of a subset of proteins and annexin V apoptosis assays. Trx-interacting protein (TXNIP) was overexpressed by transfection and protein expression was determined by immunoblotting. Pharmacological inhibition of Trx by 1-methyl-2-imidazolyl-disulfide (PX-12) reduced viability of three GBM cell lines, induced expression of active caspase-3, and reduced phosphorylation of AKT-kinase and expression of β-catenin. Sensitivity to cisplatin could be restored by both PX-12 and recombinant expression of the upstream Trx inhibitor TXNIP, respectively.
In addition, PX-12 also sensitized primary human GBM cells to temozolomide. Combined inhibition of Trx and the phosphatidylinositide 3-kinase (PI3K) pathway resulted in massive cell death. We conclude that the Trx system and the PI3K pathway act as a sequential cascade and could potentially present a new drug target.
AbstractThis paper discusses the comparison of two methods to achieve thermal comfort utilising air conditioning (AC) system in a small indoor space – adaptive control and fuzzy control. Thermal comfort indoors is performed to provide comfortability individually or for a group of people. Due to the small indoor space which usually a bit cramped, crowded and less airy, the ambience can be very uncomfortable either for doing sedentary or active work, thus the AC system can be very useful to provide thermal comfort. Both methods can be utilised depending on how thermal comfort is viewed and how the level of thermal comfort is decided. Every method has its own advantage and limitations, and will be covered in this paper as well.
On 25 May 2011, the OECD launched a "Green Growth Strategy" and proposed a "Green Growth Diagnostics" approach to identify the binding constraints on green growth. This paper discusses the potential use and usefulness of this approach as a means to identify those binding constraints. It is argued that the approach is best used at the meso level for industries and certain environmental challenges. The paper proposes a modified green growth diagnostics approach for eco-innovations at the meso level that can be useful for informing and organising a rational policy dialogue amongst all stakeholders.
This paper documents the design, implementation and evaluation of the Unfolding Space Glove—an open source sensory substitution device. It transmits the relative position and distance of nearby objects as vibratory stimuli to the back of the hand and thus enables blind people to haptically explore the depth of their surrounding space, assisting with navigation tasks such as object recognition and wayfinding. The prototype requires no external hardware, is highly portable, operates in all lighting conditions, and provides continuous and immediate feedback—all while being visually unobtrusive. Both blind (n = 8) and blindfolded sighted participants (n = 6) completed structured training and obstacle courses with both the prototype and a white long cane to allow performance comparisons to be drawn between them. The subjects quickly learned how to use the glove and successfully completed all of the trials, though still being slower with it than with the cane. Qualitative interviews revealed a high level of usability and user experience. Overall, the results indicate the general processability of spatial information through sensory substitution using haptic, vibrotactile interfaces. Further research would be required to evaluate the prototype’s capabilities after extensive training and to derive a fully functional navigation aid from its features.
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 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
The southeast of Córdoba province used to be originally covered by hundreds of wetlands that got heavily modified or drained in the last few decades. Since wetlands provide various important ecosystem services (ESS) for human well-being, their degradation created several problems in La Picasa basin, among which floods are the most obvious one. The wise use of wetlands is increasingly acknowledged to be part of nature-based solution approaches reducing disaster risk. However, in the study area these approaches remain a relatively new concept to decision makers and the lack of knowledge on their effectiveness and implementation process poses a serious barrier to their adoption.
To overcome this obstacle, this dissertation applies an ESS perspective on the current problems of La Picasa basin and sets it in a context of socio-ecological system (SES) theory. A comprehensive analysis of (1) the role wetlands have played in the historic development of the SES, (2) important stakeholder dynamics that create opportunities or restrictions for the conservation of wetlands and (3) possible management approaches to inverse negative ESS trade-offs and feedback loops, was performed.
Results demonstrate that the current problems of floods have both natural and anthropogenic causes. In this regard, wetlands hold a vital role in the complex historic interactions between the social and ecological drivers of changes in the water balance. Although a social network between stakeholders exists, several conflicts prevent a proper functioning of a basin-wide integrated management concept based on wetland restoration. Nature-based solution approaches, putting wetlands in the center of attention of future management strategies, were found to hold a high potential to reduce the risk of floods and, as a side-effect boost biodiversity and habitat quality in the study area.