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Discovering the Significance of Housing Neighbourhoods by Assessing Their Attributes With a Digital Tool
No full textMuch of the building stock subjected to the upcoming European Renovation Wave is neither listed as heritage nor considered valuable architecture. This also applies to Dutch housing built between 1965 and 1985, more than 30% of the Dutch housing stock, for which there is no consensus on their cultural significance. Their successful renovation process requires broad support. What attributes do citizens consider significant in their neighbourhood? How do we include a multitude of stakeholders? And can digital methods help collect and process responses? This article reveals significant attributes of residential neighbourhoods from 1965 to 1985, assessed by various stakeholders with a digital tool based on case studies in Amsterdam and Almere. A mobile application allowed individuals to identify significant attributes at various scales while visiting the neighbourhood. By qualitative data analysis of survey and interview results, groups of tangible and intangible attributes were deduced. Results show that identifying attributes by current stakeholders broadens existing expert-led assessments on 1965–1985 neighbourhoods by including, for example, generic attributes not originally intended by the designers. Asking open-ended questions is considered essential to identify undiscovered attributes by alternative stakeholders, although dealing with large numbers of responses is recognised as a challenge to cluster and classify. Lastly, the mobile application appears to be a useful digital tool, but integrating scientific consistency and usability is recommended for further development. Engaging multiple stakeholders with such mobile applications allows for collecting opinions, anticipating conflicts, or shared interests between stakeholders and integration into renovation designs. It can empower citizens to preserve the neighbourhood attributes that are most significant to them.Heritage & ArchitectureReal Estate Managemen
Criminal, Cosmopolitan, Commodified: How Rotterdam’s Interwar Amusement Street, the Schiedamsedijk, Became a Safe Mirror Image of Itself
No full textThis chapter develops a layered analysis of the Schiedamsedijk, Rotterdam’s interwar amusement street. It links the street’s split socio-cultural character to that of port cities in general, and investigates this along the lines of a similar divide in perceptions of safety and security. Based on an historical bird’s-eye view of the pleasure area, the Schiedamsedijk’s criminal and cosmopolitan sides are discussed. Both of these maritime urban traits were neutralised when the Schiedamsedijk reinvented itself as a domestic tourist attraction in the late 1930s. Through visual sources, interchanges are foregrounded between contrasting internal and external perspectives on safety, which ultimately help to nuance and reframe the stereotypical characters and ambiguous nature traditionally ascribed to this historical environment of pleasure culture.'The Cultural Construction of Safety and Security' was made possible by a grant from: Open Access Stimuleringsfonds; HERA project ‘Governing the Narcotic City. Imaginaries, Practices, Discourses and Consequences of Public Drug Use’; Faculty CW Open UniversiteitHistory, Form & Aesthetic
Between a Day and a Lifetime: Integration of short-stay housing and the sharing economy in the post-war neighborhood of Groot-IJsselmonde, Rotterdam
No full textUrban densification is essential to keep the green spaces surrounding Dutch cities, especially in the Randstad. The current Dutch housing stock, of which a significant portion was built during the 1960's and 1970's, lacks a flexible layer in which people in urgent need of housing can find (temporary) affordable housing. Short-stay housing, which encompasses people living somewhere for a day, up to a couple of years, could provide this flexible layer. Target groups for short-stay housing fare well by social interaction, stimulating integration into Dutch society and opening up new possibilities in their life. This social interaction can be partially provided by introducing the sharing economy into an existing neighborhood, providing sustainable options regarding ownership or mobility.The project 'Between a Day and a Lifetime' therefore proposes an urban densification strategy in which a short-stay housing concept, based on principles of co-housing and the sharing economy, creates densification in a way that it enriches the lives of the current ánd future inhabitants.Architecture, Urbanism and Building Sciences | Advanced Housing Desig
Failure anticipation scheme in distribution systems based on wave distortions and Montecarlo methods
No full textAnticipating failures is vital for maintaining a reliable power supply. Advanced measurement devices in the grid generate vast data that contains valuable information on grid operations. Initial signatures of an incipient failure are often reflected in this data in the form of electrical waveform distortions. Conventional protection schemes are not equipped to analyze these distortions and anticipate failures. There is a considerable research gap for a simple yet robust and universal failure anticipation and diagnosis scheme. This paper proposes a universal Failure Anticipation and Diagnosis Scheme (FADS) to detect incipient failures in AC distribution grids. The method comprises three short stages, helping the operator make an informed decision. In the first stage, the FADS scheme leverages the fundamental properties of electrical sinusoid waveforms to detect distortions. In the second stage, the distortion data is processed through pre-determined thresholds set in accordance with the system's regular operation. In the third stage, depending on the system, the FADS uses the extent of the violations of these thresholds and ranks the severity of the danger posed to grid operations. The classification helps determine if the waveform distortions are the signature of an incipient failure. The proposed FADS method's reliability, robustness and effectiveness are evaluated in incipient failure conditions of field events modelled in real-time simulations on standardized IEEE distribution feeders. The FADS is a high-speed distortion detector, is quite sensitive, and the method has high selectivity because of its nature.Intelligent Electrical Power GridsElectrical Sustainable Energ
Fatigue Assessment of Complex Riveted Connections: A study on old steel bridges using Advanced Finite Element Analysis
No full textNumerous traffic bridges have been constructed over the last 150 years. Because bridges are commonly built based on an expected lifetime of 75 to 100 years, a large quantity of bridges are reaching the end of their design lifetime, or even are far overdue. To ensure these bridges remain operational without experiencing catastrophic failures, they have to be recalculated, and if need be, repaired, strengthened or replaced. Particularly older bridges are commonly constructed utilizing rivets. Their often overly complex geometries, the fact that riveting has become largely obsolete as a construction process, and old bridges are commonly not design for fatigue loading, engineers regularly face significant challenges when reassessing such bridges. While fatigue phenomena have been extensively investigated throughout the years, studies pertaining to the fatigue of riveted connections are relatively limited. The Eurocode on fatigue, EN-1993-1-9 includes only two detail categories. Additional guidelines, like RBK Steel expand upon these detail categories, but focus primarily on built-up beam cross-sections in riveted structures, rather than riveted connections. In order to attempt to more accurately assess the complex joints present in ancient steel bridges, this thesis attempts to answer the following question: What would be a suitable approach to model complex riveted joints and assess their fatigue life considering a balance between the level of complexity and applicability in design practice?A literature study is performed to identify the different factors that affect the fatigue resistance of riveted connections, as well as to highlight several of the available methods to perform a fatigue assessment. Through the investigation of experimental studies complemented with Finite Element (FE) Analyses, a design methodology for a full scale riveted model is drawn up, and finally a FE model of a joint of the John S. Thompsonbridge is constructed. A critical location within the joint is identified. On this critical locations, several stress- and strain-based fatigue life analyses are performed, namely the use of Stress Concentration Factors (SCF), Smith-Watson-Topper’s (SWT) strain-life equation, and the multiaxial shear strain criterion (MSSC) method, to investigate the effects of incorporating mean stress effects and multiaxiality. From these analyses, it is concluded that SCF appears to provide overly conservative fatigue life estimates, whereas SWT and MSSC provide more probable results. The increased life estimate through MSSC suggests a limited degree of multiaxiality present in the critical location. All three methods require a detailed FE model, complicating the fatigue assessment of the joint. While the SCF method is slightly simpler to use than SWT and MSSC, it does not weigh up to the conservativity of its life estimation. SWT is deemed the most suitable approach for the fatigue assessment of riveted joints, given that it is more widely applicable and relevant than MSSC.Civil Engineering | Structural Engineerin
Circular Robotic Construction
No full textIn situ robotic construction is a type of construction where mobile robotic systems build directly on the building site. To enable on-site navigation, industrial robots can be integrated with mobile bases, while mobile, high-payload construction machines can be adapted for autonomous operation. With parallel advances in sensor processing, these robotic construction processes can become robust and capable of handling non-standard, local, as-found materials.The potential of using autonomous, mobile robotic systems for the development of innovative circular construction processes is presented in three exemplary case studies:(i) robotically jammed structures from bulk materials, (ii) robotic earthworks with local and upcycled materials, and (iii) robotic additive manufacturing with earth-based materials. These processes exemplify key strategies for a circular industry through the utilisation of materials with low embodied greenhouse gas emissions and the implementation of fully reversible construction processes.For each case study, we describe the robotic building process, the enabling technologies and workflows, and the major sustainability and circularity benefits compared to conventional construction methods. Moreover, we discuss the difficulty of industry transfer, considering challenges such as detailing, integration, and engineering validation. We conclude with an outlook towards future research avenues and industry adoption strategies.Landscape Architectur
Design for urban vertical-axis wind turbines: balancing performance and noise
No full textIn urban areas, vertical-axis wind turbines (VAWTs) show promise due to their omnidirectional design, addressing challenges faced by traditional horizontal-axis turbines (HAWTs). Despite significant progress in urban VAWTs, extensive multidisciplinary research is needed to optimise their efficiency and use in such environments. This dissertation addresses this gap in four aspects. First, a low-fidelity noise model based on state-of-the-art literature is developed, allowing fast, acceptable, and accurate predictions for preliminary design stages of the primary noise sources on an urban VAWT. Then, a wind speed estimator and tip-speed ratio (WSE-TSR) tracking controller is designed to maximise the power production of an urban VAWT in turbulent wind conditions. This WSE-TSR tracking controller turned out to be an ill-posed problem, impacting the turbine and controller performance in the presence of model uncertainty. Follows the presentation of an approach that combines frequency-domain analysis and multi-objective optimisation, demonstrating its effectiveness in assessing and calibrating torque control strategies, thereby contradicting earlier assumptions and establishing new perspectives on performance optimisation for real-world wind turbines. Based on these collective findings, a decision-making framework is derived, capable of striking a balance between VAWT performance and noise acceptance, allowing for the first time to consider psychoacoustic annoyance as a metric.In summary, this thesis contributes significantly to advancing the understanding of the complex dynamics of VAWTs, specifically focusing on human acoustic perception nearby, laying the groundwork for the successful integration of VAWTs into urban landscapes.Wind Energ
Optimization of Interplant Water Reuse in Industrial Parks: Considering Water Treatment Systems
No full textReusing water is a crucial part of the solution for addressing the growing concern regarding the risk of water scarcity in industrialized and urbanized areas. This study introduces a tool for the design of water networks, focusing on water reuse in industrial parks. Utilizing a mixed-integer nonlinear programming (MINLP) model developed earlier, this tool is the first in water network design models that operates with open-source software, while considering water treatment systems and multiple constituents. A literature study is conducted to discover shortcomings in water network design models and to find a foundational model to use to develop the tool. The developed tool creates a water network based on the optimization of the costs of water obtained from water sources, the costs of treatment systems, and optionally the piping costs. The treatment systems are used to regenerate the water for reuse in industrial plants and to meet environmental discharge limits. The tool develops local optimal solutions as an output. Additionally, this study is the first to integrate a water treatment systems database into a water network design model. However, this database needs to be expanded before it is usable. This study demonstrates the tool through three case studies.Civil Engineerin
Intelligent Anomaly Detection for Lane Rendering Using Transformer with Self-Supervised Pre-Training and Customized Fine-Tuning
No full textThe burgeoning navigation services using digital maps provide great convenience to drivers. However, there are sometimes anomalies in the lane rendering map images, which might mislead human drivers and result in unsafe driving. To accurately and effectively detect the anomalies, this paper transforms lane rendering image anomaly detection into a classification problem and proposes a four-phase pipeline consisting of data pre-processing, self-supervised pre-training with the masked image modeling (MiM) method, customized fine-tuning using cross-entropy loss with label smoothing, and post-processing to tackle it using state-of-the-art deep learning techniques, especially the Transformer models. Various experiments verify the effectiveness of the proposed pipeline. The proposed pipeline can deliver superior lane rendering image anomaly detection performance, and especially, the self-supervised pre-training with MiM can greatly improve the detection accuracy while significantly reducing the total training time, e.g, Swin Transformer with Uniform Masking as self-supervised pretraining (Swin-Trans-UM) obtained better accuracy at 94.77% and better Area Under The Curve (AUC) at 0.9743 compared with the pure Swin Transformer without pre-training (Swin-Trans) whose accuracy is 94.01% AUC is 0.9498, and the fine-tuning epochs reduced to 41 from original 280. Ablation study further regarding techniques to alleviate the data imbalance between normal and abnormal instances further enhances the model performance.Transport and Plannin
A comparison of smooth basis constructions for isogeometric analysis
No full textIn order to perform isogeometric analysis with increased smoothness on complex domains, trimming, variational coupling or unstructured spline methods can be used. The latter two classes of methods require a multi-patch segmentation of the domain, and provide continuous bases along patch interfaces. In the context of shell modelling, variational methods are widely used, whereas the application of unstructured spline methods on shell problems is rather scarce. In this paper, we therefore provide a qualitative and a quantitative comparison of a selection of unstructured spline constructions, in particular the D-Patch, Almost-C1, Analysis-Suitable G1 and the Approximate C1 constructions. Using this comparison, we aim to provide insight into the selection of methods for practical problems, as well as directions for future research. In the qualitative comparison, the properties of each method are evaluated and compared. In the quantitative comparison, a selection of numerical examples is used to highlight different advantages and disadvantages of each method. In the latter, comparison with weak coupling methods such as Nitsche's method or penalty methods is made as well. In brief, it is concluded that the Approximate C1 and Analysis-Suitable G1 converge optimally in the analysis of a bi-harmonic problem, without the need of special refinement procedures. Furthermore, these methods provide accurate stress fields. On the other hand, the Almost-C1 and D-Patch provide relatively easy construction on complex geometries. The Almost-C1 method does not have limitations on the valence of boundary vertices, unlike the D-Patch, but is only applicable to biquadratic local bases. Following from these conclusions, future research directions are proposed, for example towards making the Approximate C1 and Analysis-Suitable G1 applicable to more complex geometries.Numerical AnalysisShip and Offshore Structure