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Supercapacitor Internal Resistance Mitigation for Rapid Inertia Emulation of Renewable Power Generation
No full textInertia emulation control (INEC) using supercapacitors (SC) has become an appealing approach to effectively enhance the frequency stability of modern low-inertia power grids. However, considerable internal resistance (IR) existing in commercially available SCs may adversely degrade the speed and accuracy of SC-based inertial response, which has been neglected by existing INEC schemes. To tackle this issue, this article proposes an SC IR mitigation (SCIRM) for rapid INEC, consisting of an online IR identification module to obtain up-to-date IR value through fictitious frequency ramp injection and an IR mitigation control to compensate for the voltage deviation across the identified IR. The small-signal stability of the SCIRM-based rapid INEC scheme is strengthened through control parameter optimization. The effectiveness of the scheme in correcting SC inertial response as well as promoting power system frequency stability is evaluated through experimental verifications using a 10 kW testbed and simulation studies using a modified IEEE 39-bus New England system.</p
Towards stable metal organic-inorganic complex glasses
No full textMetal organic-inorganic complex (MOIC) glasses have emerged as a new family of hybrid glasses. However, the low thermal stability of MOIC glasses fabricated via crystallization suppression constrains their practical applicability under ambient conditions. Here, we report a novel approach for preparing the MOIC glasses that combines slow-solvent removal with subsequent quenching to avoid gel thermal decomposition and enhance the thermal stability of the obtained glass. Specifically, the new approach utilizes an aprotic solvent (acetone) to kinetically prevent the ordering of the metal-ligand complex molecules in solution, thereby suppressing crystallization and forming a gel. The subsequent gradual drying process leads to the removal of the solvent to enhance the connections between molecules through hydrogen bonds, thus causing the formation of a hydrogen-bonded network. The increased network connectivity lowers the mobility of the molecules, thereby enhancing the thermal stability of the system. A disordered network of dried gel is frozen-in via cooling from 130 °C to room temperature, and hence, MOIC glass forms. Structural analyses reveal that hydrogen bonds are responsible for connecting the tetrahedral units. The as-prepared MOIC glass exhibits an increase in glass transition temperature (Tg) during rapid room-temperature relaxation, enhanced CO2 uptake, and a red shift in photoluminescence. This work not only presents a novel strategy for fabricating large-sized, stable, functional MOIC glasses but also uncovers the critical role of hydrogen bonds in MOIC glass formation
The effect of implementing colon capsule endoscopy in colorectal cancer screening on participation and sociodemographic inequalities:A parallel group randomised controlled trial
Get PDFOBJECTIVES: Significant sociodemographic inequalities in participation in colorectal cancer (CRC) screening programmes across the globe are evident. We aimed to investigate the effect of introducing colon capsule endoscopy (CCE) as a filter test in faecal immunochemical test (FIT)-based CRC screening on overall FIT participation and social inequalities in FIT participation.STUDY DESIGN: We conducted a randomised controlled trial, randomising 368,452 individuals.METHODS: Both groups received an invitation to submit a FIT sample, which elicited a follow-up investigation if ≥ 20 μg haemoglobin/g faeces was detected. The control group followed the standard screening pathway and was referred for follow-up colonoscopy. The intervention group were free to choose between colonoscopy and colon capsule endoscopy.RESULTS: The overall FIT participation proportion was significantly lower in the intervention group (63.4 %), compared to the control group (64.9 %). All sociodemographic subgroups in the intervention group had lower participation proportions than their control group counterpart, with an average of 1.4 (range 0.3-2.7) percentage points lower participation. The odds of non-participation, divided by sociodemographic characteristics, were not significantly different between interventions and controls for any subgroup, except for those aged 55-59 in which the odds ratios for non-participation was 1.59 (1.54-1.65) in the control group and 1.48 (1.43-1.53) in the intervention group, comparing them to those aged above 70.CONCLUSIONS: Introducing a free choice between colon capsule endoscopy and colonoscopy if FIT positive did not increase FIT participation in CRC screening. Further, it did not affect the pattern of social inequalities in FIT uptake.</p
The Impact of Graph Structure, Cluster Centroid and Text Review Embeddings on Recommendation Methods
Get PDFIt is generally accepted that collaborative information is important for the performance of recommender systems. It is also generally accepted that if this information is sparser, it impacts recommendation systems negatively. Various approaches have tried to lift this problem by employing side information. However, global patterns that can be provided by clusters of similar items and users or even additional information such as text are often not used together with collaborative information. We study the impact of integrating clustering embeddings, review embeddings, and their combinations with embeddings obtained by a recommender system. We study the performance of this approach across various state-of-the-art recommender system algorithms including graph-based methods. We highlight that graph structures are important with sparser datasets and both, in knowledge graphs with side information as well as in collaborative bipartite graphs. In less sparse datasets, a collaborative bipartite graph is usually sufficient. We also highlight that the improvement of recommendation performance through clustering, particularly evident when combined with review embeddings is most visible on sparser data, while on less sparse data incorporating review embeddings may be sufficient when combined with one of the graph-based methods, or otherwise when combined with clustering in other methods
Using artificial neural networks for anomaly detection in infrared thermography images for rapid diagnosis in an emergency care unit
Get PDFInfrared thermography (IRT) has emerged as an affordable, rapid and noninvasive complement to widely adopted yet resource-demanding medical imaging techniques such as MRI, CT scans and X-rays, offering diverse applications in the medical field. While IRT hardware is well established and capable of providing high-quality thermographic images, the analysis of such images often requires well-trained experts. Current state-of-the art methods for computer-aided IRT analysis rely on statistical tests of temperature gradients between control points, which are suboptimal because they do not fully exploit the available information regarding spatial temperature distributions. This paper addresses this issue by incorporating artificial neural networks (ANN) into the IRT analysis workflow. We focused on a particular case in which the IRT was utilized in the emergency department (ED) for predicting 30-day mortality, thereby contributing to improved diagnosis and patient care in emergency medicine. In total, the IRT images of 214 patients were analyzed. Various ANN-based approaches were considered in this study, and the best results were obtained using an anomaly detection model based on a variational autoencoder (VAE), which achieved promising results for detecting abnormal images. This paper comprehensively presents all the analysis details as well as recommendations regarding image preprocessing, augmentation, and potential enhancements of the models
Multi-material and thickness optimization of sandwich structures subject to failure criteria
No full textSandwich structures are essential for lightweight design, but their multi-material composition introduces complexities, particularly additional failure modes that must be addressed during design. Structural optimization provides an efficient means to manage these complexities and accelerate development of high-performance designs. Discrete Material and Thickness Optimization (DMTO) enables such optimization of general multi-material and multi-layered structures with varying thickness. The objective of this work is to extend the DMTO framework for sandwich structure design by incorporating sandwich failure criteria. The problems are parametrized using the Discrete Material and Direct Thickness Optimization (DMDTO), a variant of DMTO, allowing the layer thickness to vary independently in each sandwich face sheet and core. A sandwich failure analysis approach that includes key sandwich failure criteria is presented in this context, particularly shear crimping and face wrinkling criteria — novel additions within multi-material and thickness optimization. These criteria are formulated to allow utilizing efficient gradient-based solvers with adjoint design sensitivity analysis to compute problem gradients. Several numerical examples are solved to demonstrate the approach, including a simplified wind turbine blade main spar that highlights the potential for industrial application of the approach
Exploring the Interdisciplinary Dimensions of Second-Wave Ubiquitous Music.
No full textCFPLeonardo – Special Section: Exploring the Interdisciplinary Dimensions of Second-Wave Ubiquitous MusicCo-editors:Damián Keller Anthony (aka Tony) L. BrooksMartin K. Koszolko1 Full Professor Music Technology, Federal University of Acre and Federal University of Paraiba, Brazil2 Professor Emeritus Aalborg University, Denmark3 Lecturer in Music Industry, the University of Newcastle, Australia Ubiquitous music (ubimus) is an emergent field of research that combines several areas from sound and music computing, human computer interaction, creativity studies, and music education, with a strong social and community underpinning. The term owes its origins to concepts and ideas around ubiquitous computing, connecting with the principle that deep technologies “weave themselves into the fabric of everyday life until they are indistinguishable from it.” (Weiser, 1991). Frequently, it is assumed that music is ubiquitous in society but, more often than not, it is experienced in a passive way. Our perspective on ubiquitous music as a field of study aims to foster new opportunities for creative participation, open to all.Since its beginnings in 2007, ubimus has featured a variety of artistic, social, andtechnological perspectives that highlight the field’s potential for applications in diverse contexts. While the impact of the emergent infrastructures for music makingremains central in ubimus debates, the social and cognitive dimensions of ubimusresearch has gained strength due to the deployment of ubimus resources for educational and artistic endeavours. For instance, a topic such as creativity – increasingly tied to cultural and social factors (Glăveanu, 2013) – has been adopted as a relevant theme of ubimus research (Keller and Lazzarini, 2015).Furthermore, the push for the adoption of technological infrastructure in both public and domestic settings is increasingly being subjected to critical analysis. Ubimus' proposals explore the artistic possibilities of music-making incorporating casual participants with no formal musical training. Thus, both musicians and non-musicians are potential stakeholders. These mixed modes of participation have unveiled opportunities to repurpose Internet of Things resources and multisensorial-interaction techniques to address the limitations of the current infrastructure, beyond the standard artistic venues. These practices incorporate the extant technological resources and also highlight the emergent social and cognitive demands of activities tailored for everyday settings. Hence, rather than a genre-oriented trend, second-wave ubiquitous music proposals may be characterised as a movement that targets music-making as a universal right, skewing the imposition of hegemonic and prepackaged aesthetic choices. In line with the above, this special section/series, whilst focusing upon featuring expanded versions of peer-reviewed texts from the annual conferences Ubiquitous Music Symposium (to be held in Morelia, Mexico, in 2025) and ArtsIT2024 (held in New York University, Abu Dhabi, November 2024), is open for text submissions by others interested in the ubiquitous music topic. Relevant topics include the active ubimus threads featured in the references below, plus the exploration of interdisciplinary connections involving music for well-being, domestic ubimus, everyday musical creativity, multisensorial strategies for musical interaction, and the incorporation of large language models in creative music-making. An aim of this special section/series is the elaboration of a second-wave manifesto that condenses several of the major trends that emerged in ubimus research since 2015.Schedule:March-April 2025: deadline for article submission3 November 2025: final drafts (after revisions)Early 2026: publicationReferencesBrooks, A. L. (1999). Virtual interactive space (V.I.S.) as a movement capture interface tool giving multimedia feedback for treatment and analysis, Int. Congress of The World Confederation for Physical Therapy (WCPT), Yokohama, Japan. WCPT/Science Links Japan.Brooks, A. L. (2007). Special Issue on ArtAbilitation, Digital Creativity, 18(2).Brooks, A. L. (2011). Intelligent Decision-Support in Virtual Reality Healthcare & Rehabilitation. Springer Studies in Computational Intelligence, 326, 143-169. Brooks, A. L. (2020). Special Issue on Shifting Boundaries: Practices and Theories, Arts and Technologies, Digital Creativity, 31(3). Brooks, A. L. (2023). Creating Digitally: Shifting Boundaries: Arts and Technologies - Contemporary Applications and Concepts. Springer Intelligent Systems Reference Library.Brooks, A. L. and Hasselblad, S. (2004). CAREHERE - Creating Aesthetically Resonant Environments for the Handicapped, Elderly and Rehabilitation: Sweden, Int. Conf. on Disability, Virtual Reality, and Associated Technologies. Oxford University, pp. 191–198.Brooks, A. L. and Petersson, E. (2005). Recursive reflection and learning in raw data video analysis of interactive 'play' environments for special needs health care, Healthcom 2005: The 7th International Workshop on Enterprise networking and Computing in Healthcare Industry. Busan, Korea, 23-25 June. IEEE/Korea Multimedia Society, pp. 83-87.Glăveanu, V. P. (2013). Rewriting the language of creativity: The Five A's framework. Review of General Psychology 17(1), 69-81.Keller, D., Lazzarini, V. and Pimenta, M. S. (eds.) (2014). Ubiquitous Music, Vol. XXVIII, Berlin and Heidelberg: Springer International Publishing.Keller, D. and Lazzarini, V. (2015). Special Issue on Creativity-Centered Design and the Digital Arts. Journal of Cases in Information Technology 17, i-v.Keller, D., Lazzarini, V. and Schiavoni, F. (2019). Ubiquitous music: Perspectives and challenges. Journal of New Music Research 48(4).Koszolko, M. K., Studley, T. (2023). From Site-Specific Sampling to Gamification: An exploration of performative engagement with the environment. Organised Sound 28(3), 338-351.Lazzarini, V. and Keller, D. (2021). Editors’ notes: Geysers, bacteria, electricity, and a flippin’ pompom'. Computer Music Journal 44(1), 6-16.Lazzarini, V., Keller, D., Otero, N. and Turchet, L. (eds.) (2020). Ubiquitous Music Ecologies. London: Taylor & Francis (Routledge).Weiser, M. (1991). The Computer for the 21st Century. 265(3), 94–101. Issue EditorsDamián Keller is a Full Professor of Music Technology at the Federal University of Acre and the Federal University of Paraíba, Brazil. Co-founder and member of the research network Ubiquitous Music Group, he has published over two hundred papers on ubiquitous music and ecologically grounded creative practice. He is currently associate editor of the Journal of Cases in Information Technology (Vancouver), and Arts & Communication (Singapore).Anthony (aka Tony) Brooks is emeritus affiliated to Aalborg University Denmark. His research spanning from mid 1980s to 2000 led to European and Danish multi-million euros funded projects, an industry start-up, and commercial product. National, international and fellow conferred awards align with Brooks’ approx 250 publications that include six patents, 12 books, and a music CD album. He is Danish representative under The International Federation for Information Processing (IFIP) and steering chair under the European Alliance for Innovation (EAI) of ArtsIT (Arts and Technology, Interactivity, and Game Creation) conf. Martin K. Koszolko is a researcher, music, and video producer. His research interests include the affordances of mobile music-making technologies and remote music collaboration practices. He has presented at national and international seminars and conferences and has published in the fields of collaborative and mobile music production. Martin is Lecturer in Music Industry at the University of Newcastle in Australia and serves as the vice-president of Clan Analogue, Australia’s longest-running electronic music collective. He is an award-winning music producer known for his creative work under the KOshowKO, Philosophy of Sound, and iubar project monikers, as well as his contributions to over 50 releases on multiple record labels.<br/
Temporal trends in loss of expected lifetime associated with cardiovascular complications following newly diagnosed atrial fibrillation:a Danish nationwide cohort study from 2000 to 2022
No full textAims While advancements in care may improve the clinical course of atrial fibrillation (AF), data on trends in lost lifetime after developing cardiovascular complications are sparse. Methods and results In this nationwide registry-based matched cohort study (1 January 2000-31 December 2022), we followed patients with ischaemic stroke, gastrointestinal bleeding, intracranial bleeding, heart failure (HF), and myocardial infarction (MI) after AF and matched referents with AF. We estimated the average loss of life expectancy as the difference in restricted mean survival time between patients with AF with and without a complication and compared the loss between 2000-10 and 2011-22. We followed 27 809 patients with ischaemic stroke, 28 938 with gastrointestinal bleeding, 7710 with intracranial bleeding, 50 914 with HF, and 14 141 with MI and their matched referents. The loss of lifetime improved for ischaemic stroke [-2.1 vs. -1.8 years; difference 4.0 months, 95% confidence interval (CI) 2.4-5.6; P < 0.001]. We found no evidence of trends for gastrointestinal (-1.7 vs. -1.8 years; difference -0.8 months, 95% CI -2.5 to 0.8; P = 0.32) or intracranial bleeding (-3.3 vs. -3.1 years; difference 1.6 months, 95% CI -1.3 to 4.6; P = 0.28). The loss of lifetime improved for HF (-2.1 vs. -1.9 years; difference 2.4 months, 95% CI 0.9-3.8; P = 0.001) and MI (-1.6 vs. -1.1 years; difference 5.9 months, 95% CI 3.3-8.5; P < 0.001). Conclusion Among patients with AF, the loss of expected lifetime after incident ischaemic stroke, HF, and MI improved modestly over the past two decades but not after gastrointestinal or intracranial bleeding. These findings support the development and evaluation of interventions that prevent and reduce severity of complications after AF, particularly for bleeding.</p
Feedback-based quantum strategies for constrained combinatorial optimization problems
Get PDFFeedback-based quantum algorithms have recently emerged as potential methods for approximating the ground states of Hamiltonians. One such algorithm, the feedback-based algorithm for quantum optimization (FALQON), is specifically designed to solve quadratic unconstrained binary optimization problems. Its extension, the feedback-based algorithm for quantum optimization with constraints (FALQON-C), was introduced to handle constrained optimization problems with equality and inequality constraints. In this work, we extend the feedback-based quantum algorithms framework to address a broader class of constraints known as invalid configuration (IC) constraints, which explicitly prohibit specific configurations of decision variables. We first present a transformation technique that converts the constrained optimization problem with invalid configuration constraints into an equivalent unconstrained problem by incorporating a penalizing term into the cost function. Then, leaning upon control theory, we propose an alternative method tailored for feedback-based quantum algorithms that directly tackles IC constraints without requiring slack variables. Our approach introduces a new operator that encodes the optimal feasible solution of the constrained optimization problem as its ground state. Then, a controlled quantum system based on the Lyapunov control technique is designed to ensure convergence to the ground state of this operator. Two approaches are introduced in the design of this operator to address IC constraints: the folded spectrum approach and the deflation approach. These methods eliminate the need for slack variables, significantly reducing the quantum circuit depth and the number of qubits required. We show the effectiveness of our proposed algorithms through numerical simulations