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Mapping the field of urban infrastructuring:A scoping review
Get PDFInfrastructuring denotes the processual nature of infrastructure development and the dynamic relationship between infrastructures, actors, and the environment in specific local contexts. In this scoping review, we aim to map the existing academic literature on processes and practices of co-developing urban infrastructures through collaborative knowledge production and geospatial methods. Our main research question is: What trends and directions can be identified in research on the sociotechnical processes and relational system of urban infrastructuring, and how are methods of participation and knowledge building conceptualized and realized in infrastructuring processes? We are approaching these questions both qualitatively and quantitatively. We will show that there are three aspects where urban infrastructuring needs more attention. First, there is a lack in long-term or longitudinal research on infrastructuring processes. Secondly, while innovative work is being done in Majority World countries, there is scope for theory building that considers local context as well more interdisciplinary work. Thirdly, a stronger focus on prototyping is needed in order to create links between conceptual and practical as well as processual aspects of infrastructuring. This review will help to better understand the complexities of urban infrastructuring and provide insights for future research
Patient perceptions around the use of clinico-pathologic and genomic tools in the management of early breast cancer
No full textPurpose: Clinico-pathologic (including nomograms) and genomic tools are widely used to determine prognosis and predict benefit from treatment in early breast cancer (EBC). However, little is reported on patient perceptions of these tools and whether they enhance understanding of their individual risk of recurrence or benefits from therapy. Methods: Patients with EBC were surveyed to evaluate the use of prognostic/predictive tools in clinical practice and their self-reported recurrence risk. Their actual risk of local, contralateral and distant recurrence was estimated using the INFLUENCE 2.0 tool. Information was also collected on key aspects that patients wanted these tools to address, as well as the anticipated benefits that would make receiving chemotherapy worthwhile from their perspective. Results: Completed surveys were received from 210 patients. Despite the use of NHS PREDICT 2.1 in 50% (105/210) and Oncotype DX in 10.9% (23/210) of patients, only 26% (45/210) stated they knew such a test had been performed. There was a mild association between patient self-assessment of distant recurrence risk and their actual risk as per INFLUENCE 2.0. When asked to rank what they wanted from prediction tools, patients identified chance of metastases (36.1%, 56/155) and chance of being disease free (31.3%, 46/147) as most important. Patients would consider chemotherapy if the survival benefit was ≥ 1% (31, 17.7%), 2–5% (23, 13.3%), 5–10% (24, 13.7%), ≥ 10% (36, 20.6%). These thresholds for benefit were significantly lower for patients who had received chemotherapy compared with those who had not. Conclusion: Despite the widespread use of prognostic and predictive tools, patients often appeared unaware that one had been used. This may in part explain the lack of relationship between self-perceived and actual risk of disease recurrence.</p
Identifying Infrastructure Demand and Performance Changes Through Agent-Based Modelling Using Fuzzy Logic
Get PDFRenewing and upgrading infrastructure is crucial for addressing societal, technological, and environmental challenges. Yet, such interventions can temporarily disrupt infrastructure availability, causing ripple effects on interconnected networks. This can alter user and stakeholder behavior, impacting demand and performance. In transportation, unavailable routes can increase costs, prompting alternative choices. Unfortunately, infrastructure agencies often neglect the behavioral aspects and uncertainty of freight forwarders’ mode choice. To address this, a fuzzy logic approach is proposed to model mode choice in an agent-based simulation. Fuzzy logic accommodates imprecise data and subjective uncertainties in decision-making. Demonstrated in a Dutch multi-modal freight network case study, this model reveals how interventions affect mode choice and demand shifts. It offers valuable insights for infrastructure managers, aiding demand and performance estimation. Levers can be evaluated for their potential to promote modal shifts, enhancing environmental, functional, and safety aspects of transport networks
Exploring the AMD<sup>®</sup>Deep Learning Processor Unit for Accelerating Selective Sweep Detection
No full textDetecting selective sweeps, the genomic signature of positive selection, is fundamental to understanding evolutionary processes, and has many practical applications, such as identifying drug-resistant mutations in pathogens and designing more effective drug treatments. Deep Learning (DL) methods, particularly Convolutional Neural Networks (CNNs), have advanced the detection of selective sweeps by overcoming inherent theoretical limitations of traditional analytical techniques. Yet, the increased computational requirements of CNN classifiers employed within selective sweep detection frameworks hinder their practical deployment for large-scale, whole-genome scans. In this work, we explore the performance potential of the AMD® Deep Learning Processing Unit (DPU) for accelerating a state-of-the-art CNN classifier that has been designed to distinguish selective sweeps from neutral genomic regions. The DPU is a programmable engine that is specifically designed for efficient CNN inference and can be integrated into the programmable logic of modern FPGAs through a software-centric development platform, thereby not requiring extensive computer architecture or hardware design background. Deploying three DPU instances onto a ZCU102 FPGA development board delivers up to 31.1x, 10.8x, and 24.1x higher throughput (classifications per second) than a single CPU core, 6 CPU cores, and a virtual GPU (Tesla P4) in the cloud, respectively. This exploratory study showcases the potential of software-programmable hardware acceleration for boosting performance of DL-based selective sweep detection, paving the way for efficient and practical whole-genome analyses.</p
Managing science cities spaces in wider urban hierarchies:Reconciling knowledge-based and polycentric modes of urban development
Get PDFThis paper explores polycentric knowledge-based urban development in practice, asking how to create a Europe that benefits everyone involved. More specifically, it is asking whether the emergence of a new knowledge space has created a multi-urban service node, stimulating innovation and growth across a wider city-region urban field. Drawing on the case of Kennispark (Knowledge Park) in Twente region, the Eastern Netherlands, it analyses the tensions that occur between polycentric and knowledge-based urban development. The paper concludes with the possible implications of such tensions for the science cities in terms of increasing their smart specialisation
Dynamic Modeling of a Magnetic Video Capsule for Enhanced Navigation in the Gastrointestinal Tract
No full textCapsule endoscopy, a procedure wherein a patient swallows a capsule that captures images throughout the gastrointestinal (GI) tract, offers greater patient comfort compared to that of traditional endoscopy. Although preferred by patients, this method faces challenges such as capsule retention requiring surgical removal and suboptimal imaging resulting in false negative diagnoses. This work investigates the feasibility of controlling a magnetic capsule endoscope within the GI-tract by use of a robotically controlled, extracorporeal,rotating permanent magnet. A dynamic model was developed by incorporating both contact forces (friction, damping, and spring forces) and non-contact forces (magnetic forces and torques), which were then used to predict the magnetic capsule’s behaviour. The model was then validated via use of frequencyresponse testing in and outside a realistic bowel phantom. Open-loop testing within the bowel phantom further evaluated the system’s ability to navigate the GI tract. The results demonstrate that the method is feasible, and repeatable trials could be performed traversing the entire bowel phantom in under 600 s. Furthermore, the validation demonstrated that an accurate theoretical representation of the magnetic capsules behaviour is achievable, enabling precise prediction of the necessary actuation inputs
Effects of organizational complexity on high-tech systems design decisions:Insights from a Dutch equipment manufacturer
No full textHigh-tech systems are becoming extremely complex and interconnected, often requiring multidisciplinary collaboration across technical and organizational perspectives. This complexity is frequently understood through a System of Systems (SoS) lens, where multiple interdependent systems interact to achieve overarching goals. Such system complexity is reflected in the organizational complexity, where each influences the other. However, the effects of such organizational complexity on high-tech systems design decisions remain understudied. In this paper we present insights from a study conducted at a Dutch high-tech equipment manufacturer, focusing on how organizational complexity contributes to knowledge-related inefficiencies in decision-making. The model based on the Design Research Methodology (DRM), is grounded in a case study of the Cooled Mirror (CM) feature at a Dutch high-tech equipment manufacturer, providing real-world insights into early-stage design challenges faced by Systems Engineers. It illustrates the causal relationships between organizational complexity, knowledge scattering, knowledge flow inefficiencies, and decision quality. Our empirical findings, supported by the literature, reveal that knowledge scattering is a critical factor impacted by organizational complexity, leading to decision inefficiencies and misalignment across Systems Engineering roles
Towards the use of triple ionic-electronic conducting lanthanum tungstate as a hydrogen separation membrane
No full textThis thesis investigates the potential of triple ionic-electronic conducting lanthanum tungstate (LWO, La28−xW4+xO56-δ) as a hydrogen separation membrane. LWO is a fluorite structured material with an inherently deficient oxygen sublattice. It exhibits high chemical stability against reducing and acidic paired with high protonic conductivity, making it a promising candidate as a hydrogen separation membrane, provided its electronic conductivity is enhanced. However, predicting the membrane performance remains challenging due to the limited availability of material properties, including thermodynamic parameters related to defect formation, as well as concentrations and mobilities of the involved charge carriers (H+, O2-, e-). This research aims to evaluate the phase stability, as well as the transport and thermodynamic properties of compositions derived from LWO and to predict their performance as a hydrogen separation membrane.Chapter 1 describes the motivation and aims of the research, addresses fundamental principles of solid oxide cells, focusing on protonic conductors, and elaborates on triple ionic-electronic conductors and their potential applications in hydrogen-related technologies. In Chapter 2, the phase stability of LWO is investigated, with a particular focus on the impact of partial substitution of W by Nb, Mo, Mn, or Fe. In Chapter 3 a novel approach for evaluating both transport and thermodynamic parameters of triple ionic-electronic conducting oxides is presented. Chapter 4 presents the development and validation of a defect transport model based on the Nernst-Planck-Poisson equation set, enabling the deconvolution of the total electrical conductivity transient into its constituent partial conductivity transients. In Chapter 5, a transport model is developed for calculation of the steady-state permeation fluxes through triple ionic-electronic conducting membranes and is validated for pure and molybdenum-doped LWO membranes. In Chapter 6, the oxygen ion and proton transport properties of La5.4WO11.1-δ are investigated using electrical conductivity relaxation following hydration and dehydration steps at constant oxygen partial pressure. The results show that the magnitude of the applied current significantly affects both the electrical conductivity and the relaxation behavior. Finally, Chapter 7 provides recommendations for future research on the development of triple ionic-electronic conducting membranes for hydrogen separation
Evolution and instability of the tip vortices behind a yawed wind turbine
No full textYaw control can effectively enhance wind farm power output, but the vorticity distribution and coherent structures in yawed turbine wakes remain poorly understood. We propose a physical model capable of accurately predicting tip vortex dynamics from their generation to destabilisation. This model integrates a point vortex framework with advanced blade element momentum theory and vortex cylinder theory for yawed turbines. Comparisons with large eddy simulations demonstrate that the model effectively predicts the vorticity distribution of tip vortices and the wake profile of yawed turbines. Finally, we employ sparsity-promoting dynamic mode decomposition to analyse the dynamics of the far wake. Our analysis reveals four primary mode types: (i) the averaged mode; (ii) shear modes; (iii) harmonic modes; and (iv) merging modes. Under yawed conditions, these modes become asymmetric, leading to interactions between the tip and root vortex modes. This direct interaction plays a critical role during the formation process of the counter-rotating vortex pair observed in yawed wakes.</p
The governance of global land sector semantic resources:status and pathways
No full textKnowledge Organization Systems (KOS) enable Semantic Web and Linked Data implementations. KOS in terms of the Linked Land Governance Thesaurus (LandVoc) and the Cadastre and Land Administration Thesaurus (CaLAThe) render concepts of the ISO 19152:2024 Land Administration Domain Model. These all support more shared and standardized understandings in the land domain. Concept mapping is presented, and an explicit integration of thesauri and knowledge bases is illustrated for education and community engagement. The paper reflects on the integration of CaLAThe into the LandVoc and AGROVOC context. The establishment of a less strict semantic facility, supporting ad hoc teaching tasks, is motivated.</p