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Grading recommendations for enhanced patient safety in sentinel event analysis: the recommendation improvement matrix
No full textObjectives The goal of sentinel event (SE) analysis is to prevent recurrence. However, the rate of SEs has remained constant over the past years. Research suggests this is in part due to the quality of recommendations. Currently, standards for the selection of recommendations are lacking. Developing a method to grade recommendations could help in both designing and selecting interventions most likely to improve patient safety. The aim of this study was to (1) develop a user-friendly method to grade recommendations and (2) assess its applicability in a large series of Dutch perioperative SE analysis reports. Methods Based on two grading methods, we developed the recommendation improvement matrix (RIM). Applicability was assessed by analysing all Dutch perioperative SE reports over a 12-month period. After which interobserver agreement was studied. Results In the RIM, two elements are crucial: whether the recommendation intervenes before or after an SE and whether it eliminates or controls the hazard. Applicability was evaluated in 115 analysis reports, encompassing 161 recommendations. Recommendation quality varied from the highest, category A, to the lowest, category D, with category A accounting for 44%, category B for 35%, category C for 2% and category D for 19% of recommendations. There was a fair interobserver agreement. Conclusion The RIM can be used to grade recommendations in SE analysis and could possibly help in both designing and selecting interventions. It is relatively simple, user-friendly and has the potential to improve patient safety. The RIM can help formulate effective and sustainable recommendations, a second key objective of the RIM is to foster and facilitate constructive dialogue among those responsible for patient safety.Safety and Security Scienc
Crustal conductivity footprint of the Miocene porphyry copper polymetallic deposits in the Gangdese metallogenic belt, Tibetan Plateau
No full textNew evidence worldwide has linked the surface locations of mineral deposits and their crustal-scale electrical conductivity footprint. We examine the relationship between the Gangdese Miocene porphyry copper deposits, Tibetan Plateau, and the electrical conductivity signature from a three-dimensional model generated from 311 magnetotelluric measurements. The distribution of electrical resistivity throughout the crust and the conductance within the mid-lower crust (depth range of 25–70 km) is analyzed. The results clearly show that the large and ultra-large Miocene porphyry copper deposits coincide spatially with conductive zones and areas of very-high conductance (>10,000S) in the mid-lower crust. Computations are undertaken to determine the influence of water-bearing silicate melts and alkali-bearing (Na+ and K+) fluids on conductivity. Based on this, the bulk conductivity is interpretated to be caused by a system of alkali-rich volatile-rich partial melt. The alkali-rich volatile-rich magmatic-hydrothermal fluids facilitate the migration and concentration of metal ions originating in deep areas. The volumes necessary are much less than partial melt alone and can thus help to reconcile large conductivity variations with small seismic velocity variations. The electrical structure indicates the magma source area of anatexis in the lower crust, a multi-stage magmatic system with large mid-crustal and small upper-crustal magma reservoirs, and complex pathways related to rift zones. We determine that the conductive zones in the mid-lower crust have an influence on the development of the mineralization and the location of the mineral belt.Applied Geophysics and Petrophysic
An Anticipatory Approach to Ethico-Legal Implications of Future Neurotechnology
No full textThis paper provides a justificatory rationale for recommending the inclusion of imagined future use cases in neurotechnology development processes, specifically for legal and policy ends. Including detailed imaginative engagement with future applications of neurotechnology can serve to connect ethical, legal, and policy issues potentially arising from the translation of brain stimulation research to the public consumer domain. Futurist scholars have for some time recommended approaches that merge creative arts with scientific development in order to theorise possible futures toward which current trends in technology development might be steered. Taking a creative, imaginative approach like this in the neurotechnology context can help move development processes beyond considerations of device functioning, safety, and compliance with existing regulation, and into an active engagement with potential future dynamics brought about by the emergence of the neurotechnology itself. Imagined scenarios can engage with potential consumer uses of devices that might come to challenge legal or policy contexts. An anticipatory, creative approach can imagine what such uses might consist in, and what they might imply. Justifying this approach also prompts a co-responsibility perspective for policymaking in technology contexts. Overall, this furnishes a mode of neurotechnology’s emergence that can avoid crises of confidence in terms of ethico-legal issues, and promote policy responses balanced between knowledge, values, protected innovation potential, and regulatory safeguards.Values Technology and InnovationEthics & Philosophy of Technolog
EquiCity game: a mathematical serious game for participatory design of spatial configurations
No full textWe propose a mathematical framework for developing social-choice games that are designed to mediate decision-making processes for city planning, urban area redevelopment, and architectural configuration of urban housing complexes. The proposed framework features a digital serious gaming approach for participatory design to support transparency and inclusion in the process of decision-making and ensure an equitable balance of sustainable development goals in spatial design outcomes. The mathematical process consists of a Markovian design machine for balancing the design decisions of actors, a massing configurator equipped with fuzzy logic and multi-criteria decision analysis, algebraic graph-theoretical accessibility evaluators, and automated solar-climatic evaluators using geospatial computational geometry. We demonstrate the effectiveness of the framework by implementing a multi-player online game that facilitates a participatory decision-making workshop for forming multi-functional building complexes by providing a generative configurator equipped with automated appraisal/scoring mechanisms for revealing the aggregate impact of alternatives. The EquiCity game empowers a group of decision-makers to reach a fair consensual spatial design by mathematically simulating many rounds of reasonable trade-offs between their decisions, with different levels of interest or control over various types of investments. The novelty of the framework is in its capability to encompass decision-making about the most idiosyncratic aspects of a site related to its heritage status and cultural significance to the most generic aspects such as balancing access to sunlight for the site while respecting ‘the right to sunlight’ of the neighbours of the site, ensuring coherence of the entire configuration with regards to a network of desired closeness ratings, the satisfaction of a programme of requirements, and intricately balancing individual development goals in conjunction with communal goals and environmental design codes.Heritage & Architectur
Inclined quadrotor landing using on-board sensors and computing
No full textAchieving autonomous inclined landing would be an important step towards quadrotors which are able to land anywhere and under any conditions. If a quadrotor is able to safely land anywhere, even when a landing platform is not available, this would open up many useful applications. Firstly, the quadrotor could safely land whenever its battery levels get low or when contact with an operator is lost. Secondly, the quadrotor could be used for different applications, such as reconnaissance, search and rescue, infrastructure or delivery services. There are many challenges to the field of autonomous inclined quadrotor landing. Firstly, landing safely on an inclined surface without the use of a perching mechanism requires that the quadrotor has a low approach velocity. The quadrotor should also land at the same angle as the inclination of the landing surface. To meet these constraints, the quadrotor will be required to perform an agile landing maneuver. Furthermore, the quadrotor will also have to estimate its attitude, position and velocity towards the platform during the landing maneuver. Due to the agile landing maneuver, landmark-based localization of the quadrotor will be more difficult, since these methods require the quadrotor's on-board camera to be directed at a certain landmark which can be used for guidance. Current methods for autonomous inclined landing either use external sensors or a landing mechanism to deal with the presented challenges. During this project, an algorithm is developed which can estimate the quadrotor's attitude, position and velocity during the landing maneuver, while using only on-board sensors. State estimations are generated using two sources: a landmark-based localization algorithm and a Visual-Inertial Odometry (VIO) algorithm. The landmark-based localization algorithm uses markers placed near the landing surface to determine the quadrotor's attitude and position relative to the landing platform. Estimations from these two systems are fused by an Extended Kalman Filter (EKF). Furthermore, we train a policy network in a deep reinforcement learning approach for control of the quadrotor during the landing maneuver. We use a field-of-view constraint during the training of this policy network to keep markers used by the localization algorithm in sight of the quadrotor's on-board camera sensor during the landing maneuver. During a series of experiments in the Gazebo simulator, we validate performance of the state estimation system during the inclined landing maneuver. We show that the marker localization algorithm's performance is improved by implementing a field-of-view constraint during the training of the policy network. We also show that state estimation by the EKF outperforms the two individual state estimation algorithms. In the Gazebo simulator, the quadrotor is able to use the state estimation system to land without the use of external sensors.Mechanical Engineering | Vehicle Engineering | Cognitive Robotic
The potential role of airborne and floating wind in the North Sea region
No full textNovel wind technologies, in particular airborne wind energy (AWE) and floating offshore wind turbines, have the potential to unlock untapped wind resources and contribute to power system stability in unique ways. So far, the techno-economic potential of both technologies has only been investigated at a small scale, whereas the most significant benefits will likely play out on a system scale. Given the urgency of the energy transition, the possible contribution of these novel technologies should be addressed. Therefore, we investigate the main system-level trade-offs in integrating AWE systems and floating wind turbines into a highly renewable future energy system. To do so, we develop a modelling workflow that integrates wind resource assessment and future cost and performance estimations into a large-scale energy system model, which finds cost-optimal system designs that are operationally feasible with hourly temporal resolution across ten countries in the North Sea region. Acknowledging the uncertainty on AWE systems' future costs and performance and floating wind turbines, we examine a broad range of cost and technology development scenarios and identify which insights are consistent across different possible futures. We find that onshore AWE outperforms conventional onshore wind regarding system-wide benefits due to higher wind resource availability and distinctive hourly generation profiles, which are sometimes complementary to conventional onshore turbines. The achievable power density per ground surface area is the main limiting factor in large-scale onshore AWE deployment. Offshore AWE, in contrast, provides system benefits similar to those of offshore wind alternatives. Therefore, deployment is primarily driven by cost competitiveness. Floating wind turbines achieve higher performance than conventional wind turbines, so they can cost more and remain competitive. AWE, in particular, might be able to play a significant role in a climate-neutral European energy supply and thus warrants further study.Energy and IndustryWind Energ
Governing Prometheus: Ethical Reflections On Risk & Uncertainty In Solar Climate Engineering Research
No full textThis thesis explores the ethical challenges that a potential research program for solar climate engineering via Stratospheric Aerosol Injection (SAI) could incur. These ethical challenges are comprised of epistemic hurdles in relation to the research process, as well as societal questions of justice and the value of nature. The thesis proposes a variety of tools and approaches to assess and possibly govern the risks and uncertainties invoked by the research of SAI and its societal implications. The methodological approach is based mainly on ethical and philosophical analysis and reflection and the main findings take the form of discursive argumentation and normative reflection. SAI is a form of climate engineering that seeks to reduce global warming by increasing the planet’s reflection levels through the injection of reflective agents (aerosols) into the stratosphere. The mere potential of researching a technology that would actively intervene in the global climate is highly contentious and has led to passionate debates throughout the expert community. Designing a research process for such a polarizing technology such as SAI inevitably raises fundamental moral questions, wherein issues of global justice, democracy, the value of and humanity’s relationship with nature, and the societal impacts of technological innovation all intersect. Given these far-reaching consequences, the thesis operates under the assumption that SAI is a highly disruptive idea and technology, that has the potential to challenge and undermine existing societal values and institutions. Accordingly, this work presents a range of philosophical modes of inquiry and assessments, in order to supply any proposed SAI research governance program with the necessary ethical considerations and frameworks. The thesis is structured along four major inflection points, which form the individual chapters tied together through differing but interrelated research questions. What follows is an overview of the research questions, along with a brief description of how those questions were answered…Ethics & Philosophy of Technolog
Road Safety and Welfare
No full textRoad crashes are a worldwide societal problem and they have a negative impact on welfare. This is reflected by several types of social costs that result from road crashes, including medical costs, loss of human productive capacities and damage to vehicle and other properties, as well as intangible impacts such as loss of quality of life and life years. This thesis is about this impact of road crashes on welfare and the socio-economic benefits of improving road safety. Understanding the impact of road crashes on welfare is important for evidence-based road safety policy making. It helps to justify road safety investments and to allocate resources efficiently.The thesis is aimed at critically assessing the literature and current practices for estimating the impact of road crashes and road safety measures on welfare and at improving and applying methods for estimating these impacts. A combination of different methods is used, in particular literature reviews on the social costs of road crashes and monetary valuation of preventing non-fatal injuries, a survey among experts on road crash costs in European countries, a case study on the social costs of road crashes in middle-income country (Kazakhstan) and the development of a methodology for cost-benefit analysis with novel elements with respect to non-fatal injury prevention.Estimates of the impact of road crashes on welfare are found to vary widely across countries (the equivalent of 0.4-6.0% of GDP), which is mainly explained by methodological differences. In many countries the welfare impact of road crashes is found to be underestimated due to methodological shortcomings. International harmonization of methods and developing new international guidelines for estimating the social costs of road crashes is recommended. Furthermore, the results show that non-fatal injuries constitute a major portion of the overall welfare impact of road crashes. However, they often receive insufficient attention in economic assessments of road safety. Improved methods for monetary valuation and for including non-fatal road injuries in cost-benefit analysis are presented.Transport and Logistic
Exploring transitions of sewer wastewater infrastructure towards decentralisation using the modular model TURN-Sewers
No full textWe present a new modular model called TURN-Sewers for exploring different adaptations of centralised wastewater infrastructure towards more decentralised wastewater systems under different urban development scenarios. The modular model is flexible and computationally efficient in exploring transitions at the city scale, allowing for the comparison of different policies and management strategies for sanitary wastewater infrastructure. TURN-Sewers includes independent modules that simulate the generation, dimensioning, deterioration, management, and calculation of performance indicators for different wastewater systems. This model can use readily available spatial information to support infrastructure planners and other stakeholders in exploring different transition pathways from centralised to decentralised wastewater infrastructure. An illustrative example demonstrates how TURN-Sewers can generate multiple future alternatives, define different infrastructure management strategies regarding system expansion, rehabilitation and transition, and assess the economic, hydraulic and structural impacts.Policy Analysi
Post-service analysis of the degradation and protective mechanisms of chromate-based structural aircraft coatings
No full textThe substitution of chromate-containing structural coating systems in aviation with alternatives complying with nowadays strict environmental, health and safety regulations remains a formidable challenge. This complexity is partly due to the absence of a standardized from-test-to-market methodology, including a performance comparison between chromate-containing and alternative coating systems. To address this gap, the present study delves into the identification of crucial degradation factors that merit inclusion in such a methodology. Concurrently, it investigates the protective mechanisms inherent in chromate-containing coating systems and proposes improvements that can be applied to alternative coating systems. This study entails a comprehensive post-service examination of the degradation of paint applied to an aircraft component with over 35 years of service, employing electrochemical, microscopic and spectroscopic techniques. The findings underscore the role of thermo-oxidation as a significant degradation factor in the aging process of such coatings. Furthermore, the investigation elucidates a notable phenomenon in which aluminium ions within the coating pores form an aluminium hydroxide gel onto which chromate adsorbs. This process contributes to an increase in pore resistance upon exposure to electrolyte, leading to a self-healing barrier effect within the coating. Remarkably, this self-healing mechanism continues to offer long-term protection even when the coating matrix is sub-optimally cured due to application errors. Furthermore, this study reveals that the significant changes in capacitance during immersion testing result primarily from inhibitor leaching, emphasizing the effectiveness of combining Electrochemical Impedance Spectroscopy (EIS) with Scanning Electron Microscopy (SEM) analysis for studying coating degradation.Team Arjan Mo