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AI as an innovation in the method of innovation: implications for productivity growth
No full textGeneral-purpose technologies (GPTs) such as steam, electricity, and information and communication technologies (ICT) have historically reshaped production possibilities and transformed macroeconomic performance. Artificial intelligence (AI), and in particular recent advances in generative and predictive models, appears to share these characteristics: broad applicability, rapid improvement, complementarity with other technologies, and the capacity to reorganize production at scale.
This paper develops and implements a measurement framework for evaluating AI’s contribution to labor productivity growth. We view AI both as a GPT and an innovation in the method of innovation (IMI) that raises the efficiency of intangible asset creation. Intangibles—software, data assets, R&D, organizational capital, brand and marketing assets (following Corrado, Hulten, and Sichel 2009)—play a central role in innovation and organizational change in modern economies (Corrado et al. 2022), suggesting that the capacity for these assets to propagate productivity improvements through
their economy-wide use is substantial
Effects of OWC geometry on total energy efficiency and turbulent dissipation
No full textThis study investigates the impact of front and back wall geometries on the performance of oscillating water column (OWC) devices embedded in a fixed caisson breakwater. Combining experimental and numerical approaches, we analyse vortex formation and energy efficiency in relation to draft designs. Experiments, conducted at the Hydrodynamics Laboratory, Imperial College London, explores widest variety of draft shapes in the literature, including sharp and rounded profiles. Large eddy simulations (LES) were conducted using OpenFOAM® at laboratory and field scales to assess scale effects. The simulations accurately reproduce experimental data and reveal how draft geometry influences vortex dynamics, turbulence, and energy efficiency. It is shown that the design of the front and back drafts of an OWC can have a profound impact on its energy efficiency. In quantifying the generation of turbulence across different geometries, guidance is provided towards the most efficient geometries as well as the effects of physical model scale. Physical insight in this study provide clear recommendations for practical considerations in the design of OWC
Distance‐dependent stray field decay in magnetically stable remanence carriers: implications for magnetic microscopy
No full textMicropaleomagnetic analysis offers a path to high-precision reconstructions of ancient magnetic fields from terrestrial and space-returned samples by inverting the vertical stray field of individual particles to recover their magnetic moments through the use of magnetic microscopes. Constraining such inversions requires a detailed understanding of how domain state influences the dipolar and non-dipolar components of the stray field with distance. Here, we use micromagnetic solutions of remanent states in real, irregular sub-to near-micron magnetite particle morphologies to calculate vertical stray fields at various heights, evaluating how dipolar and non-dipolar signals can be recovered with both simple Cartesian dipole and multidipolar models in the presence and absence of noise. Our results show that single-domain and single-vortex state (SV) particles produce strong dipolar anomalies that attenuate rapidly, limiting reliable detection to observation heights below ∼1 μm for 5 nT noise or ∼0.5 μm for 50 nT noise. Larger SV or multivortex particles remain detectable to ∼5−10 μm but with reduced moment fidelity. Multipolar components decay orders of magnitude faster than the dipole and are quickly lost in noise at practical distances. Dipole-only inversions yield stable, accurate results beyond ∼2 μm, while multipolar fits can improve near-surface accuracy but add significant uncertainty in noisy data. Because strongly non-dipolar anomalies observed at heights≳1 2μm may arise from large multidomain particles or from the combined response of short- and long-wave signals of clusters of particles, they should be interpreted with caution. We highlight the need to minimize sensor noise, optimize standoff distance, and carefully interpret signals for robust micropaleomagnetic measurements
Public involvement insight report: Proposed project on the role of sleep, hearing and eyesight problems in the prevention of dementia
No full textA public involvement session on a proposed project to explore the role of sleep, hearing and eyesight in dementia preventio
The Wolfe Island Archive
No full textThe Wolfe Island Archive exists as a Blog.Throughout time historical periods have been identified by the things that were produced and the technologies used to create them. This exhibition asks ‘what will we leave behind?’ and ‘how will we be remembered?’
Mary O’ Neill’s practice drawings inspiration from museum objects and the structures and methods of museums themselves to produce work that re-vivifies objects that have lost their use value by being entombed in the museum. A necessary part of preservation is the compromise that objects that were made to be used, touched, worn, that has ritual value, must now be kept in a highly controlled environment where the knowledge they embody is often reduced to their appearance and aesthetic value.
For The Wolfe Island Archive O’Neill has produced a ‘hoard’ of artefacts allegedly found on an uninhabited island. The accompanying narrative describes the discovery of the hoard; the research carried out on the island and ultimately the reason for the demise of its inhabitants
Consensus and Divergence in Explainable AI (XAI): Evaluating Global Feature-Ranking Consistency with Empirical Evidence from Solar Energy Forecasting
No full textopen access articleThe growing reliance on solar energy necessitates robust and interpretable forecasting models for stable grid management. Current research frequently employs Explainable AI (XAI) to glean insights from complex black-box models, yet the reliability and consistency of these explanations remain largely unvalidated. Inconsistent feature attributions can mislead grid operators by incorrectly identifying the dominant drivers of solar generation, thereby affecting operational planning, reserve allocation, and trust in AI-assisted decision-making. This study addresses this critical gap by conducting a systematic statistical evaluation of feature rankings generated by multiple XAI methods, including model-agnostic (SHAP, PDP, PFI, ALE) and model-specific (Split- and Gain-based) techniques, within a time-series regression context. Using a LightGBM model for one-day-ahead solar power forecasting across four sites in Calgary, Canada, we evaluate consensus and divergence using the Friedman test, Kendall’s W, and Spearman’s rank correlation. To ensure the generalizability of our findings, we further validate the results using a CatBoost model. Our results show a strong overall agreement across methods (Kendall’s W: 0.90–0.94), with no statistically significant difference in ranking (p > 0.05). However, pairwise analysis reveals that the “Split” method frequently diverges from other techniques, exhibiting lower correlation scores. These findings suggest that while XAI consensus is high, relying on a single method—particularly the split count—poses risks. We recommend employing multi-method XAI and using agreement as an explicit diagnostic to ensure transparent and reliable solar energy predictions
Wastewater seasonal characterization and evaluation of reclamation potential of biological nutrient removal processes: a case study in Türkiye
No full textThe file attached to this record is the author's final peer reviewed version. The Publisher's final version can be found by following the DOI link.This paper investigates the performance of biological nutrient removal (BNR) processes for wastewater reclamation potential. A case study of three conventionally designed BNR plants in Kocaeli, Türkiye evaluated the seasonal profile of their nutrient removal efficacy and potential reduction of their effective discharge into the receiving water bodies. The key parameters studied included - chemical oxygen demand (COD), biochemical oxygen demand (BOD), suspended solids (SS), total nitrogen (TN), total phosphorus (TP), and heavy metals. The analysis showed that effluent COD, BOD, SS, TN and TP concentrations of all three BNR plants were below 90, 20, 21, 9.2 and 1.2 mgL− 1 respectively, in compliance with the discharge limits set by the Turkish Water Pollution Control Regulations and the United Nations Food and Agricultural Organization for all the seasons. Further statistical analyses of the samples indicated that the data from all three BNRs followed a normal distribution, with p values generally greater than 0.05. Within the scope of analysis, no statistically significant differences were detected among the three BNRs. Beyond the current use of wastewater from the three plants for agricultural usage, further integration of dedicated wastewater recovery units is recommended alongside conventional BNR processes for enhanced wastewater reclamation for industrial and municipal applications
Negotiating the grounds for (in)voluntary psychiatric detention in public spaces: a case study of NFL star Everson Griffen
No full textThis chapter highlights the ways in which mental health and law enforcement services intersect, when witnesses and emergency services professionals report, assess, and categorise on-going events in light of emerging information and incidents. This work involves a complex web of welfare, wellbeing, safety, security, and criminal concerns, that must be considered by professional parties to determine whether an individual will be taken to a hospital for mental health evaluation or the police station in relation to potential ‘criminal charges’.
The chapter draws on ethnomethodology and conversation analysis to examine two high-profile instances of (in)voluntary psychiatric detention of American Footballer, Everson Griffen. Due to Griffen's public status, numerous publicly available data sources (e.g. police traffic camera footage, police documents, media content, social media posts and team announcements) were captured, enabling a re-construction of Griffen’s real-time ‘erratic’ actions and behaviour. This provides a rich context for understanding the practical, interactional and organisational issues involved in ‘working up’ assessments of public mental health crises and/or criminal conduct in real-time as events evolve. Likewise for ordinary citizens, witnessing these worrying actions, making sense of risk/safety and wellbeing/welfare issues can create practical problems to navigate (e.g. which emergency service to contact and how to describe what they have seen)
Automating the Hartman-Schijve methodology for predicting interlaminar fatigue crack growth in fibre composites
No full textThe Hartman-Schijve methodology offers a direct route to calculating various fatigue crack growth (FCG) rate curves that are associated with delaminations growing in fibre polymer-matrix composites. However, up to the present, only a ‘manual’ method has been described to deduce the values of the Hartman-Schijve constants that are needed for such calculations. Whilst this manual method may give reasonably acceptable results for calculating the Hartman-Schijve constants, it is a difficult and tedious implementation route. Thus, it may, if the operator is inexperienced, give relatively large errors in the values of the key constants that are needed to calculate the FCG rate curves. Furthermore, for very large data sets there is great difficulty incurred in manipulating such a large amount of data using the ‘manual method’.
Therefore, the main aim of the present paper has been to introduce a novel computer model and the associated software, ‘Zencrack: Material Curve Fitting Utility’ from Zentech International Limited, UK, to obtain automatically the Hartman-Schijve constants. The aim has been to deduce the ‘worst-case upper-bound’ FCG curve for small, naturally-occurring, delaminations in the composite material, or component. To achieve such an ‘automatic’ method, the current work (a) has taken previously-published algorithms that employ a ‘Total Least Squares’ method for the fitting process of the experimental input data to the Hartman-Schijve equation and (b) has investigated the effect of a normalising scaling factor. It is shown that an automatic calculation that includes all the input data gives the best representation of the Hartman-Schijve constants and is the recommended approach
The effect of early diagenetic processes on the quantification of fossil micrometeorite abundance and flux in the geological record
No full textFossil micrometeorites (MMs) recovered from lithified sedimentary rocks, particularly iron-rich (I-type) cosmic spherules (CSs) provide valuable insights into past dust-forming events. Their abundances, when combined with estimates of local sedimentation rates can be used to reconstruct the flux of extraterrestrial dust. However, their preservation in the geological record is highly susceptible to postdepositional diagenetic processes, complicating their quantification and past flux calculations. This study investigated lenticular calcitic concretions as potential sites of enhanced preservation of fossil MMs. A total of 17–18 I-types (but no silicate dominated spherules, S-types) were recovered from Cenomanian sediments within the Cretaceous Chalk Supergroup at Lulworth Cove, England. The I-types, identified by optical and SEM–EDX analyses, exhibited typical dendritic textures and varying degrees of alteration, including mottled surfaces and loss of Ni and Cr by leaching. Calcitic concretions yielded a comparable concentration of I-types to the surrounding hosting marl, but due to the added carbonate cementation during their growth, preservation per original sediment volume was shown to be enhanced (potentially by up to ~60%). Calcitic concretions can therefore act as microenvironments that enhance fossil MM preservation by limiting complete dissolution and loss of I-types. To constrain possible diagenetic effects on fossil MM quantification, future studies should compare cosmic dust yields across multiple sites exposing the same targeted sedimentary horizon