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Calculating flood probability in Obihiro using a probabilistic method: incorporating the probability of dike failure with uncertainty
No full textIn Japan, estimating flood risk follows a deterministic approach. A probabilistic risk method, as adapted in the Netherlands, would be better suited for the quantitative evaluation of flood damage. This study applies such a method in Obihiro, Hokkaido, northern island of Japan. We modelled dike failure with the mechanism overtopping. The probability of dike failure is calculated with a Monte Carlo simulation, considering uncertainties in water levels, critical flow velocity, and dike heights. This results in more accurate failure probabilities compared to the deterministic approach. Additionally, we corrected the dike failure probability for upstream dike failures because these reduce downstream water levels. This conditional flood probability is about 1/10th of the independent situation, indicating a significant effect of considering dike failure in dependence on upstream failures.Hydraulic Structures and Flood Ris
A set of calculation tools supporting the design, modelling and application of plywood-based seismic retrofitting interventions on timber floors in existing buildings
No full textThe application of timber-based strengthening solutions to existing wooden and masonry structures, combines several benefits, such as reversibility, compatibility, lightness, sustainability, affordability, and effectiveness. With reference to existing timber floors, an efficient method to enhance their seismic response is the fastening of an overlay of plywood panels to the existing sheathing, an intervention that greatly improves in-plane strength, stiffness, and energy dissipation. In order to promote the use of this retrofitting solution in practice, this work presents a set of calculation tools supporting the design and advanced numerical modelling of timber diaphragms strengthened with plywood panels. The suite of tools allows to first estimate the full nonlinear, cyclic in-plane response of the strengthened diaphragms starting from the geometrical and material properties of the existing sheathing and the plywood overlay, as well as the mechanical characteristics of the fasteners. As second step, such estimated in-plane response can be transformed into a constitutive law for performing nonlinear numerical simulations, by means of a user-supplied subroutine developed for finite element software DIANA FEA. The presented calculation examples and the performed validation against reference studies from literature, show that the developed tools can provide an accurate estimate of the in-plane response of the diaphragms, and enable an efficient numerical simulation of their seismic behaviour. The implemented tools can be used to both obtain preliminary indication for plywood-based seismic retrofitting design, and to calibrate the interventions on existing diaphragms based on the specific characteristics and needs of a building, relying on the adaptability and versatility of this strengthening method.Bio-based Structures & Material
AgriNature: Transitioning Agricultural Practices to Integrate Nature
No full textThe Netherlands holds the title of the world’s second-largest exporter of agricultural goods, primarily due to Wageningen University’s pioneering research and innovation. However, this success has led to significant challenges. Intensive farming practices have strained resources and disrupted local water and soil cycles, sparking protests from frustrated farmers. Moreover, the quality of fresh water in the Dutch Delta has deteriorated due to pollutants like NO2 and PO4, exacerbated by increasing salinization pressure from the North Sea. This linear system has resulted in waste accumulation and biodiversity loss, endangering both agriculture and natural ecosystems’ sustainability.To address these challenges, our goal is to integrate nature into existing agricultural practices, thus restoring a balance with local ecosystems. The AgriNature project aims to achieve this by analysing the interplay between agriculture and nature, assessing water and soil management spatially, and fostering a participatory approach with farmers. The first phase of this transition starts with engaging farmers who are already implementing sustainable methods like agroforestry and saline agriculture, the project establishes Living Labs for co-creation, knowledge sharing, and policy influence. Waterboards and governmental agencies will mediate and provide support, connecting farmers to stakeholders and creating financial incentives. The project also recognizes the necessity of a protein transition towards more plant-based or lab-grown alternatives, aiming to decrease nitrogen pollution and eventually rewild cattle. In the second phase, AgriNature plans to expand innovations to other farmers and establish Agroparks as hubs for innovation and technology. Consumer awareness centres will promote understanding of the protein transition and the need for biodiversity. A nature regeneration centre will oversee rewilding efforts and flood risk management using nature-based solutions. The third phase will future proof these efforts by continuing innovations within the established research and development networks.Ultimately, AgriNature envisions a symbiotic relationship between agriculture and nature, empowering farmers as stewards of the land and promoting ecologically sensitive practices. Through multidisciplinary collaboration and integration of natural cycles into urban planning and agriculture, the project aims to serve as a global model for sustainability, fostering soil health, water conservation, and biodiversity preservation.AR2U086 R&D Studio – Spatial Strategies for the Global MetropolisArchitecture, Urbanism and Building Sciences | Urbanis
Human Interaction in Tabular Data Augmentation in Data Science Workflows
No full textThe advancement of artificial intelligence (AI) has led to an increased demand for both a greater volume and quality of data. In many companies, data is dispersed across multiple tables, yet AI models typically require data in a single table format. This necessitates the merging of these tables and the selection of optimal features for the model, a process known as Tabular Data Augmentation (TDA). With the rapid growth of TDA, automated tools have been developed to streamline this process. However, these state-of-the-art tools often make assumptions about user workflows that may not align with the actual needs of data specialists, potentially making them efficient yet not fully user-friendly. Additionally, without thorough evaluation through user studies, these tools may overlook critical steps in the TDA process. This thesis is divided into two main parts. The first part is dedicated to uncovering the assumptions and oversights within current TDA research through an exhaustive review of recent literature. This is followed by conducting interviews with 19 data specialists. These discussions aim to verify the identified assumptions and reveal any missing elements in state-of-the-art research. The second part focuses on creating a new tool to meet the requirements identified from validated assumptions and the gaps discovered. This tool is then subjected to evaluation interviews to assess its effectiveness. The findings indicate that data specialists prefer a TDA tool that offers enhanced control and deeper insights into the data augmentation process. To meet these preferences, Human in the Loop AutoTDA was developed, embodying the desired functionalities. Feedback from the evaluation phase confirmed that data specialists find Human in the Loop AutoTDA suitable for their TDA workflows, marking a significant advancement in the field.Git of the project: https://github.com/delftdata/hci-auto-featComputer Scienc
The Elevated Streets in Plan van Gool
No full textThis article delves into the architectural design of Plan van Gool, situated in Amsterdam's Buikslotermeer neighbourhood, with a particular focus on its concept of elevated streets. Through an examination of archival research, literature and reference projects like Brinkman's Spangen block and Auguste Perret's Le Havre, the research investigates the function of these elevated streets and their role in shaping community dynamics and urban environments. Drawing comparisons with other architectural projects, the study underscores the significance of elevated streets in promoting social cohesion and equality within residential complexes. Additionally, interviews with early residents provide insights into community formation. The findings suggest that elevated streets of Plan van Gool primarily serve practical functions like reducing stairwells and increasing access to daylight, while the undervalued other design decisions play a vital role in creating affordable, adaptable housing and nurturing a sense of anonymity, which is in turn responsible for social diversity, equality and ultimately a cohesive sense of community.AR2A011Architectural History ThesisArchitecture, Urbanism and Building Science
An integrated approach to implementing opportunity charging for electric buses: A case study of Rotterdam
No full textThe introduction of electric buses (EBs) is required in order to achieve global greenhouse emission goals. However, operating an electric bus fleet (EBF) requires careful consideration of both the mobility and energy systems in charging strategies. In literature and in real life many cases show careful consideration of only one of the systems and an oversimplification of the other, resulting in failed implementations. This paper focuses on the need for additional charging of EBs during the day using on-route opportunity charging during the on- and offboarding of passengers in residential neighbourhoods. This research aims to provide an integrated approach to bus service design, including both the mobility and energy systems. Additionally, this paper presents insights into the effect of traffic management on the feasibility of on-route opportunity charging. Two simulation tools are used for the integrated decision-making approach: SUMO and Gaia. The Simulation of Urban MObility (SUMO) software provides results regarding the energy consumption behaviour and charging needs of the EBs. Gaia provides results regarding the transformer load rate in the residential distribution grid. This paper proposes five strategies with a varying configuration of charging capacities, charging times and the introduction of traffic management via traffic priority. The five strategies are tested against three requirements: two from the mobility system and one from the energy system. The research presented uses a case study of bus line 36 in Rotterdam, the Netherlands. The results of this research show that residential neighbourhoods are often unable to handle chargers with the maximum capacity of the buses in the case study of 450 kW. A mid-range charger of 200 kW is possible in most cases. With a 200 kW charger, the on- and offboarding time of passengers is insufficient to complete daily operations. Therefore, additional charging time is necessary. Without the introduction of traffic priority, the timetable cannot be completed. With the introduction of traffic priority, travel time and energy consumption are reduced by 9.8% and 4.5%, respectively, and daily operations can be completed while satisfying the requirements of the mobility and energy systems. The results presented in this thesis suggest that an EB route design with opportunity charging is impossible without considering both mobility and energy systems simultaneously. From the mobility perspective, opportunity charging is feasible only if the charging infrastructure can meet the buses' energy needs without disrupting the schedule. From the energy perspective, it is essential that opportunity charging is implemented where and when sufficient charging capacity is available. The introduction of traffic priority allows for the satisfaction of all requirements and displays an example of the connection between mobility and energy systems.Transport, Infrastructure and Logistic
A data-driven agent-based model of occupants’ thermal comfort behaviors for the planning of district-scale flexible work arrangements
No full textIn a global context of increasing flexibility in the way workplaces and the districts in which they are located are used, there is a need for occupant-driven approaches to plan urban energy systems. Several authors have suggested the use of agent-based models (ABM) of building occupants in urban building energy simulations due to their ability to reproduce emergent behaviors from individual agents’ actions. However, few works in the literature take full advantage of the ABM paradigm, accounting for both occupant presence and energy-relevant behaviors at the district scale. In this work, we propose a methodology to develop a data-driven, agent-based model of building occupants’ activities and thermal comfort in an urban district. Our methodology combines the use of campus-scale Wi-Fi data to derive feasible occupant activity and location plans, along with thermal preference profiles derived from a longitudinal field study where off-the-shelf, non-intrusive sensors were used to capture the right-here-right-now thermal preference of 35 participants in the same case study district. Our model is then used to explore how different district operation strategies could affect building energy performance in the context of increased workspace flexibility. Our results show that by providing a diversity of building operation conditions, with different buildings having different set point temperatures, occupants’ thermal comfort hours could be improved by an average of about 10% with little effect on district energy performance. Meanwhile, a 6%–15% average decrease in space cooling energy use intensity was observed when implementing occupant-driven ventilation and setpoint controls, regardless of location choice scenario.Environmental & Climate Desig
Building Bonds, Building Safety: A Bamboo Pavilion Fostering Communities of Care
No full textThis project presents a response to the pressing issue of women's safety in public spaces, particularly in Latin American cities. Women worldwide are disproportionately affected by safety issues and fear in urban environments. I explore ways in which public spaces can enhance perceptions of safety and freedom instead. Based on extensive four months of fieldwork, including semi-structured interviews with thirty women and a survey, I identify common themes in women's experiences and propose planning and design strategies for enhancing the perception of safety. These guidelines encompass six categories: temporality and sustainability, inclusive functional programs, equal access to localized and high-quality infrastructure, planning trajectories and areas of influence, supporting existing networks of care, and creating spaces for organizing and collective action.In response to these findings, I introduce a design concept for pavilions dedicated to women, strategically integrated within the network of the UVA (Units for the Articulation of Life) in Medellín, Colombia. Through the project, I emphasize the creation of a community of mutual care among residents, exploring how bonds can form both during construction and utilization of space. These pavilions are envisioned as transformative places, where women are encouraged to actively participate in construction, subsequent management, and adaptation of the building to evolving needs. The project is tailored for community construction, ensuring local ownership and long-term sustainability.The selection of bamboo as the primary building material comes from the appreciation of its environmental sustainability benefits but also its transformative potential to empower women in construction. Being lightweight, safe, and easy to work with, it is suitable to facilitate active participation of women in the construction process. To maximize bamboo’s sustainability benefits, I complement it with a choice of biobased materials for the roof, and I propose concepts for demountable foundations and joints to ensure the circularity of the design.This project contributes to the broader debate on urban safety and social inclusion. Through addressing both social and environmental aspects of sustainability, it enhances women's safety while fostering a more equitable and resilient urban environment.Architecture, Urbanism and Building Science
Correction to: Direct observation of a crescent-shape chromosome in expanded Bacillus subtilis cells (Nature Communications, (2024), 15, 1, (2737), 10.1038/s41467-024-47094-x)
No full textCorrection to: Nature Communicationhttps://doi.org/10.1038/s41467-024-47094-x, published online 28 March 2024 The original version of this article contained an error in the “Acknowledgement “section. The original version read “We also acknowledge funding for the work in S.G. lab by the Swiss National Science Foundation (grant number: 310030L_170242).” This has been amended to “We also acknowledge funding for the work in S.G. lab by the Swiss National Science Foundation (grant number: 310030_197770).” This has now been corrected in both the PDF and HTML versions of the Article.correction to 1038/s41467-024-4709-xBN/Cees Dekker LabDynamics of Micro and Nano System
Spatial Considerations in Membrane Electrode Assembly CO2 Electrolyzers
No full textCarbon dioxide (CO2) electrolysis is an attractive technology for the production of valueadded products and hydrocarbons, establishing a route for leveraging renewable energy sources in the synthesis of fuels and chemicals. Considerable progress has been made in the past decade in advancing CO2 electrolyzers towards commercial scales, however major challenges remain for achieving practical feasibility.....ChemE/Materials for Energy Conversion and Storag
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