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From Global South to Underrepresented Geographies
No full textIn light of rapid urbanisation and the accelerating threats of climate change, scale and multitude are what set the Global North and South apart. Yet, as this course exposes, the issues faced by urban areas have resembling themes and characteristics, regardless of economic status or geographic location. Therefore, in the context of sustainable urban development, the binary dichotomy of the terms ‘Global North’ and ‘Global South’ must be contested. While a focus on Africa, Latin America and the Caribbean, Asia, and the MENA region, Rethink the City attempts to understand the transboundary nature of urban issues and provide a platform to gather insights beyond borders. It is only by learning from other narratives that we can collectively address the complex challenges ahead.Real Estate ManagementSpatial Planning and Strateg
Downscaling MODIS NDSI to Sentinel-2 fractional snow cover by random forest regression
No full textImagery acquired by the Moderate-resolution Imaging Spectroradiometer (MODIS) provides a global archive of dailyNormalized Difference Snow Index (NDSI) at 500 m nominal resolution since the year 2000. While Sentinel-2 (S2) NDSI provides an increased spatial resolution of 20 m since the year 2015, the temporal resolution amounts to only 5 days and thus lacks the high temporal resolution of MODIS. Efforts to combine NDSI datasets for an increased temporal and spatial resolution have so far focused on the deriving binary snow cover maps or combining data from other sensors. In contrast, we produce fine scale (20 m) fractional snow cover (FSC) by downscaling MODIS NDSI to S2 resolution. Random forest regression predicts S2 NDSI based on dynamic features (MODIS NDSI, day-of-year) and static, topographic features for an alpine study site. Subsequently, FSC is derived from S2 NDSI. Cross-validation results in R2 of 0.795 and RMSE of 0.155 for FSC and outperforms common resampling methods. Multi-annual S2 NDSI metrics are able to slightly improve model accuracy. Our results suggest that combining topographical data and low-resolution NDSI allows to produce daily, high-resolution S2 NDSI and FSC and improve fine scale characterization of snow cover dynamics in mountain landscapes.Mathematical Geodesy and Positionin
Notable shifts beyond pre-industrial streamflow and soil moisture conditions transgress the planetary boundary for freshwater change
No full textHuman actions compromise the many life-supporting functions provided by the freshwater cycle. Yet, scientific understanding of anthropogenic freshwater change and its long-term evolution is limited. Here, using a multi-model ensemble of global hydrological models, we estimate how, over a 145-year industrial period (1861–2005), streamflow and soil moisture have deviated from pre-industrial baseline conditions (defined by 5th–95th percentiles, at 0.5° grid level and monthly timestep over 1661–1860). Comparing the two periods, we find an increased frequency of local deviations on ~45% of land area, mainly in regions under heavy direct or indirect human pressures. To estimate humanity’s aggregate impact on these two important elements of the freshwater cycle, we present the evolution of deviation occurrence at regional to global scales. Annually, local streamflow and soil moisture deviations now occur on 18.2% and 15.8% of global land area, respectively, which is 8.0 and 4.7 percentage points beyond the ~3 percentage point wide pre-industrial variability envelope. Our results signify a substantial shift from pre-industrial streamflow and soil moisture reference conditions to persistently increasing change. This indicates a transgression of the new planetary boundary for freshwater change, which is defined and quantified using our approach, calling for urgent actions to reduce human disturbance of the freshwater cycle.Water Resource
Phase Recognition for Pulmonary Orientation Detection: Towards Automated Intraoperative Imaging Guidance
No full textObjective: This study introduces a novel deep-learning-based orientation recognition approach for detecting intraoperative lung orientation during robot-assisted anatomical resections, including lobectomy and segmentectomy. This method can potentially aid in anatomical structure identification, facilitate training and education, improve procedural efficiency, and enhance intraoperative imaging navigation. Methods: We developed a unique dataset encompassing various pulmonary procedures, being the first to report on recognition of intraoperative orientation. The TeCNO model, initially developed for laparoscopic cholecystectomies, was adapted for this study. Model performance was evaluated using accuracy, precision, recall, and F1-score, and we explored the influence of dataset composition, intraoperative factors such as 3D model presence, and visual impairments. Results: The model achieved an overall accuracy of 70%, indicating potential in recognizing lung orientation. High performance was achieved in recognizing non-surgical sequences, ‘Fissure’, and ‘Inferior’ views. ‘Posterior’ and ‘Anterior’ views showed inferior performance. Variability in performance was attributed to the heterogeneity of orientation transitions and increased complexity compared to more standardized procedures. The limited dataset size and imbalances in label distribution potentially impacted model performance. Conclusion: This study demonstrates the feasibility of applying phase recognition to detect orientation of the lung and exploring how the unique characteristics of our dataset affect model performance opposed to surgical phase recognition. The results suggest promising applications for intraoperative imaging guidance and automated adjustment of 3D models, particularly for complex orientations like the interlobar ‘Fissure view’. Future research should focus on enhancing model performance and assessing its clinical implementation in diverse surgical settings.Technical Medicin
Analysis of the Boundary Layer on a Highly Flexible Wing Based on Infrared Thermography Measurements
No full textThe effects of the wing skin distortion on the boundary layer of a highly flexible wing are analyzed in a wind tunnel experiment using infrared thermography measurements. Considerable differences in the boundary layer flow are observed when comparing the sections of the wing near the ribs, where the design shape of the wing is preserved, and in between the ribs. At the spanwise locations between the ribs, the sectional wing shape distorts and triggers boundary layer transition close to the leading edge. The differences between the design behavior of the wing and the experimental results of the boundary layer analysis demonstrate the need for considering the skin deformation and its effects on the boundary layer flow when designing highly flexible wings.Green Open Access added to TU Delft Institutional Repository ‘You share, we take care!’ – Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Aerodynamic
Reinforcement Learning for Flight Control: Evaluating Handling Qualities and Stability Properties of the PH-LAB
No full textReinforcement Learning applied to flight control has shown to have several benefits over classical, linear flight controllers, as it eliminates the need for gain scheduling and it could provide fault-tolerance. The application to civil aviation in practice, however, is non-existent as there are multiple safety concerns. This research demonstrates the evaluation of longitudinal Handling Qualities of the Soft Actor-Critic Deep Reinforcement Learning framework with the aim to translate the unpredictable black box of Reinforcement Learning into classical flight control terminology. The framework is applied to a pitch rate command system of a jet aircraft and shows robustness to off-nominal flight conditions, center of gravity shifts and biased sensor noise. Accurate tracking performance is achieved, while adhering to Level 1 longitudinal Handling Qualities for all conditions.Aerospace Engineering | Control & Simulatio
Planning Regulations and Modelled Constraints in BIM: A Dutch Case Study
No full textPlanning regulations determine a substantial part of buildings, but their constraints are usually not included in the setup of a BIM model or used explicitly for design guidance, but only tested in compliance checks once a model has been made. This is symptomatic of wider tendencies and ingrained biases that emphasize tacit knowledge and assume that information in a project starts from scratch—an assumption that runs contrary to predesign information ordering practices, as well as to the findings of creativity studies. In terms of process control, it negates important possibilities for feedforward. The paper proposes that BIM and design computerization, in general, should avoid the generate-and-test view of design, the view of design knowledge as tacit, and the adherence to analogue workflows, but develop, instead, approaches and workflows that keep information explicit and utilize it to frame design problems. To demonstrate this, we describe an exercise in which the expectation that the geometric representation of planning regulations returns permissible building envelopes was tested on the basis of a large number of cases produced by students who each collected planning regulations for a particular plot of land in the Netherlands and modelled their constraints in BIM, using a workflow that can be accommodated within the scope of predesign information gathering in any project. The results confirm that, for a large part of Dutch housing, the representation of planning regulations in BIM returns the permissible building envelope, and, so, forms a clear frame for subsequent design actions. They also suggest that including such information in the setup of a model is constructive and feasible, even for novices, and produces a bandwidth view of project information that integrates pre-existing information in a BIM workflow through feedforward. By extension, they also indicate a potential for a closer relation between analysis and synthesis in BIM, characterized by transparency and simultaneity, as well as the thorough understanding of problem constraints required for both efficiency and creativity.Design & Construction Managemen
Blockchain and fairness in the VCM: Customer-Centric Fairness: Unraveling Blockchain's Potential in Voluntary Carbon Trading
No full textCarbon trading sets a price on greenhouse gases (GHG), enabling countries and companies to buy emission rights. The carbon market includes the compliant market, regulated by governments, and the voluntary carbon market (VCM), which lacks strict regulation and allows anyone to offset emissions. In the VCM, carbon credits are created through various projects and used to compensate for emissions elsewhere.The creation of carbon credits in the VCM involves multiple stakeholders, including project developers, validation bodies, brokers, and customers. Given the differences in bargaining power between stakeholders, issues regarding fair revenue distribution exist.Blockchain technology offers promise in addressing these challenges by providing transparency and accountability. Through blockchain-enabled platforms, customers can access real-time project information, verify emissions reductions, and ensure fair revenue distribution. This transparency fosters trust and empowers customers to make informed decisions.Research on customer preferences regarding fairness in the VCM is lacking, highlighting the need to understand customer perspectives on fairness and how blockchain can enhance it. This study utilizes Q-methodology to explore customer views on fairness in the VCM.Three perspectives on fairness, named factors 1, 2, and 3, emerged from the analysis. Factor 1 emphasizes community impact, Factor 2 focuses on market participation and intermediary responsibility, and Factor 3 highlights the importance of broker transparency.Based on these findings, blockchain implementation should prioritize transparency, standardization, and credibility to increase trust and fairness in the VCM. Brokers play a crucial role in project selection, emphasizing the importance of trust and transparency. Blockchain should focus on increasing transparency throughout the project and carbon credit trading, simplifying information for brokers and enhancing market credibility. Increased transparency and understanding of project co-benefits can shift focus beyond emissions reduction, improving benefit-sharing in the VCM.This research broadens the discussion on fairness in the VCM and underscores the role of brokers in enhancing trustworthiness and credibility. Brokers should stay actively engaged in blockchain developments in the VCM. However, challenges in blockchain implementation may arise, warranting further exploration.Management of Technology (MoT
Forecasting electricity demand of municipalities through artificial neural networks and metered supply point classification
No full textThis study develops a methodology to characterise and forecast large consumers’ electricity demand, particularly municipalities, with hundreds of different metered supply points based on the previous characterisation of facilities’ consumption. Demand forecasting allows consumers to improve their participation in electricity markets and manage their electricity consumption. The method considers a classification by different types of metered supply points combined with artificial neural networks to obtain hourly forecasts using well-known parameters such as day types, hourly temperature, the last hour of electricity consumption, and sunrise and sunset time. We apply the methodology to the municipality of Valencia using over five hundred hourly load profiles for a year during 2017 and 2018. Our results present aggregated forecasts with a maximum Mean Absolute Percentage Error of 3.8% per day, outperforming the same forecast without classifying Metered Supply Points. We conclude that a correct electricity demand forecast for a consumer with different types of consumption does not need submetering, but characterising Metered Supply Points is an option with lower costs that allows for better predictions.Energie and Industri
Design for sustainable fashion: 3D weaving for denim jeans production
No full textThe fashion industry is facing complex environmental challenges, and a need for change is prevalent for the industry to move towards circular economies. 3D weaving emerges as an innovative approach to garment design and production, allowing for novel processes that capture the opportunities missed by current linear systems. 3D weaving of integrated multilayer Jacquard fabrics for denim garments shows potential for increased efficiency, reduced environmental impact, new design avenues and unprecedented levels of automation in future processes. This project sets out to research the practical application of 3D weaving for the sustainable design and production of denim garments. It explores the opportunities, limitations and execution of 3D weaving for creating a pair of 5-pocket denim jeans in existing supply chains (production samples provided by Diamond Denim). This report of the process acts as a practical guide for further adoption of 3D woven denim in academia and the industry. A production prototype is developed to showcase the benefits of 3D weaving for denim design and production, while also evaluating the implications of this particular zero waste design for 3D weaving and the industry as a whole. Evaluation of the design results suggest that this application of 3D weaving could potentially: Reduce stitch length by 40%, reduce pre-consumer waste by 20%, reduce water usage by 25%, eliminate use of micro plastics and become 100% recyclable. Further improvements are expected when the technology finds further adoption in the industry. A majority of industry respondents (n16) expressed interest in the technology, estimating that commercial application is feasible within the next 3-5 years with a production price increase that does not exceed 25% compared to conventional denim jeans. Further potential lies in tackling online returns, overstockage, made on demand systems, user customization and further optimization of the technology for increased efficiency and reduced cost. Overall, 3D weaving presents itself as a new fundamental tool in sustainable fashion design, one that requires new levels of expertise and industry alignment. Further, while future research and development helps to overcome limitations in the process of 3D weaving, the proof of concept presented in this report concludes that this process can already be done with existing machinery.Innovations such as 3D weaving may find resistance while gaining wider adoption as their implications require a major shift in current processes, often straying away from common practices that feel safer from an economic perspective. Mitigating some of the risk through development in academic settings may help to persuade businesses to adapt pivotal methods like 3D weaving sooner, as the groundwork has already been done. This underscores the need for academic research through projects focussing on sustainable design and innovation.Integrated Product Desig
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