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The Design Space of Haptics in Sports - Initial Studies and Research Agenda
Get PDFIn this paper we present a design space for haptic feedback in sports, that builds on an existing framework of interaction technology and sports. The design space allows to systematically chart applications of haptic displays for sports and physical activity, and, accordingly, also to structure evidence for design decisions. Existing and future work mapped into the design space can lead to a body of evidence that forms a basis for design guidelines on haptic displays in sports. We illustrate the design space suggested with five case studies on different types of sports. There, the applications are mapped into the dimensions of the design space, and design rationales and validation are addressed. We conclude with lessons learned and our research agenda for the design of haptic feedback applications in sports
Long-term corrosion behaviour of an ω-resistant, β-type Ti-12Cr-3Sn alloy:Effect of Sn addition on surface passivation and metal ion release in simulated physiological environment
Get PDFβ-Ti alloys are considered to be the next generation of biomaterials, mainly due to their improved biomechanical compatibility for load-bearing applications. Control of the ω phase formation kinetics by ternary additions of Sn is expected to open up opportunities for tailored biomedical implants, particularly in the context of advancing additive manufacturing techniques. However, excellent corrosion resistance in the human body environment is an essential requirement to be considered in alloy design. In this study, the effect of Sn addition (3 at.%) on the corrosion and passivation behaviour of a β-Ti-12Cr alloy in PBS is evaluated by potentiodynamic polarisation and long-term electrochemical impedance spectroscopy. Furthermore, the composition of the formed passive layer and the concentration of released ions are analysed by X-ray photoelectron spectroscopy and inductively coupled plasma optical emission spectrometry. The TiCr(Sn) alloys exhibit low corrosion rates (icorr≈42 to 52 nA cm−2) and a stable anodic passivity, especially in the body potential region. In contrast to the clinically used Ti-6Al-4V, the TiCr(Sn) alloys retain their high corrosion resistance up to 168 h of immersion with no signs of dissolution of the protective layer formed. Their passivation behaviour is governed by a Ti- and Cr-oxide layer, while the less stable Sn-oxide seems to reduce the corrosion resistance and slightly increases the passive dissolution rate. Nevertheless, the concentration of metal ions released during long-term immersion remained below the detection limit. The observed corrosion performance of the Ti-12Cr-3Sn alloy suggests that the proposed design strategy is suitable for implant applications.</p
Elastic modulus engineering in β-titanium alloys:Tuning the precipitation kinetics using Sn
Get PDFDesign strategies for β-Ti alloys either aim at the suppression of the diffusion-assisted, isothermal ωiso precipitation or at the controlled transformation of these precipitates into α phase by an ω-assisted route, with the kinetics of ωiso formation playing an essential role in both cases. Therefore, controlling the ωiso formation is pivotal in the design of β-Ti alloys with targeted properties. We propose that by controlling the Sn content added to β-Ti alloys a wide range of achievable microstructures for modulus engineering is accessible. Upon Sn addition, we observe an exponentially slowed down ωiso formation based on blocking of diffusion pathways for the β-stabiliser atoms without the transformation being thermodynamically inhibited. This suppression of ωiso formation allows the β-Ti alloys to maintain a lower elastic modulus necessary for biomedical applications. Furthermore, as byproduct, reducing the number density of ωiso precipitates upon Sn addition also impedes the ω-assisted α-formation, while the Sn-free forms fine, acicular intragranular α plates and αGB side-plates with similar morphology after low temperature pre-ageing. These results provide solid evidence for the previously proposed Sn-induced kinetic deceleration and suggest that the mechanical properties can be tailored as required by the application by tuning the ωiso precipitation kinetics using Sn.</p
Recursive regulator:A deep-learning and real-time model adaptation strategy for nonlinear systems
No full textAdaptive modeling is imperative for analyzing nonlinear systems deployed in natural dynamic environments. It facilitates filtering, prediction, and automatic control of the target object in real time to respond to unpredictable and non-repetitive sudden physical impairment caused by ambient impacts, such as corrosion, thermal drift, interference, etc. Existing nonlinear modeling approaches, however, are too complex for online training or fall short in rapid model recalibration under such conditions. To address this challenge, here we present a strategy that applies a regulator to the Koopman operator, enabling real-time model adaptation for nonlinear systems. In our approach, the regulator is directly implemented in nonlinear state-space without disrupting the pre-trained black-box predictor. The proposed technique demonstrates efficacy in capturing a broad spectrum of nonlinear dynamics and exhibits rapid adaptability to system changes without requiring offline retraining. Furthermore, its lightweight implementation and high-speed performance make it well-suited for embedded systems and applications demanding fast model recalibration and robustness.</p
Secure aggregation of sufficiently many private inputs
No full textSecure aggregation of distributed inputs is a well-studied problem. In this study, anonymity of inputs is achieved by assuring a minimal quota before publishing the outcome. We design and implement an efficient cryptographic protocol that mitigates the most important security risks and show its application in the cyber threat intelligence (CTI) domain. Our approach allows for generic aggregation and quota functions. With 20 inputs from different parties, we can do three secure and anonymous aggregations per second, and in a CTI community of 100 partners, 10, 000 aggregations could be performed during one night.</p
The feasibility of a set of physical resilience measurements in older patients admitted to the acute medical unit
No full textBackground: Most patients admitted to the Acute Medical Unit (AMU) are 60 years and older, have several multimorbidities, and are frail. During the short AMU stay, it can be challenging to determine whether these patients can recover safely at home or require an extended hospital stay. Determining physical resilience could support clinicians in deciding between discharge or prolonged hospitalization, because recovery from an acute condition is strongly related to a person’s resilience against deterioration. This research aims to evaluate the feasibility of two potential resilience measurements, sit-to-stand challenge (SSC) and grip work assessment (GWA), in acutely ill patients 60 years and older admitted to the AMU.Methods: A two-centre feasibility pilot study including 50 patients 60 years and older admitted to the AMU, the Netherlands, was conducted. Participants completed ‘The Older Persons and Informal Caregivers Survey Short Form’ about their health-related quality of life and performed the SSC and GWA in the first 48 h of admission. Patient experience with these methods was evaluated.Results: Of the participants, 46% could complete the SSC in 12 (median;q1-q3 = 10–13) minutes and 74% could complete the GWA in 5 (median;q1-q3 = 4–5) minutes. The majority of participants experienced the resilience measurements as doable and not burdensome. Significant barriers to perform measurements were a deteriorated patient condition and patients in isolation who could not be measured.Conclusion: Utilizing the GWA appeared feasible for older patients admitted to the AMU, whereas the SSC frequently presented difficulties due to clinical conditions and technical challenges.</p
Integrating space geodesy and deep learning for mapping and monitoring land subsidence hazard: A case study from the Nile Valley, Egypt
No full textLand subsidence is a widespread geohazard involving the gradual or sudden sinking of the Earth’s surface. It arises from natural processes such as soil compaction and geological conditions, as well as human activities including groundwater extraction, irrigation, and increased surface loading. Subsidence can cause significant social, economic, and environmental impacts, particularly in regions experiencing rapid population growth and intensive land and water use.This thesis addresses the lack of a regional-scale assessment of land subsidence across Egypt’s Nile Valley and Delta by providing a comprehensive InSAR-based analysis that identifies spatial patterns of deformation and highlights the most vulnerable areas. SBAS processing was carried out using LiCSBAS for the Nile Delta and GMTSAR for the entire Nile Valley, and a new Python-based workflow (SNAPWF) was developed to enable flexible PSI and SBAS processing. A ConvLSTM deep learning model, combined with SHAP explainability, was applied to quantify the relationship between land subsidence and its main environmental and anthropogenic drivers.Results from the Nile Delta show significant subsidence in coastal and reclaimed areas, with rates reaching –15 mm/year in major cities such as Alexandria, Damietta, and Rosetta. The deep learning model achieved high prediction accuracy and linked subsidence to key proxies, including land-use/land-cover change, urban load, TWS, and clay content.At the regional scale, this thesis presents the first full InSAR deformation time series of the Nile Valley, generated from 14 Sentinel-1 ascending frames and approximately 15,000 interferograms. While most of the valley remains stable, localized subsidence exceeding -12 mm/year was observed in governorates such as Port Said, Assiut, Monufia, and Qaliubiya. Applying the deep learning model across five selected regions showed that the dominant drivers vary spatially: coastal areas are influenced by Sabkha deposits, clay-rich sediments, and water fluctuations, while southern regions are more affected by geological structures, soil composition, and vegetation-related proxies.Overall, the integrated use of InSAR, deep learning, and explainable AI provides a scalable framework for identifying subsidence hotspots, understanding their key drivers, and supporting future monitoring and mitigation strategies. This approach can be adapted to other vulnerable or data-scarce regions worldwide.<br/
Quality and safety management of advanced medical technologies in home care organisations in the Netherlands: a qualitative survey at the tactical level
No full textIntroduction A quality management system (QMS) in healthcare organisations encompasses not only policies, processes and necessary procedures but also the quality, safety and risk management of medical technology. Tactical and operational decision-making levels should be closely interconnected. Previous studies have shown that nurses at the operational level do have good awareness of patient safety, but especially in teams with a strong degree of self-organisation, interaction with tactical levels is an issue. The tactical level is regarded as crucial for linking top-down policy with bottom-up experiences.Objectives To explore the perspectives of homecare employees working at a tactical level regarding (1) the quality frameworks used within their organisation according to these employees, (2) the extent to which these employees are aware of the procedures for the safe use of advanced medical technologies (AMTs), such as infusion pumps, within their organisation and (3) how these employees perceive the patient safety culture related to the use of AMTs within their organisation.Design A qualitative descriptive research design was employed.Setting and participants 15 semistructured interviews were conducted online with purposively sampled participants from homecare organisations across the Netherlands that had previously participated in related studies. The participants were employees at the tactical level within these homecare organisations, responsible for the quality and safety of AMTs.Results All participating organisations possess a QMS; however, only seven indicated that there is a dedicated plan for ensuring the quality and safety of AMTs. National protocols for the use of AMTs and the supplier’s maintenance protocols are commonly followed. Although some participants say that their organisation has no formal procedure for resolving malfunctions with AMTs, all participants know pathways for solving problems. Tailored training programmes for nurses on AMTs are provided, but often without testing knowledge and skills or formal registration of nurses’ competence. Professionals report an incident on a separate form in the electronic client file or via a separate reporting system. However, there is no uniformity within organisations about handling incidents. Most interviewees state that, in any case, incidents are discussed within the team. On the dimension ‘reporting, evaluating and learning from incidents’ of the ‘Instrument for Self-Evaluation of Patient Safety Culture’, the prevailing patient safety culture is, on average, characterised as ‘proactive’.Conclusions There is a lack of uniformity regarding quality and safety procedures for the use of AMTs in homecare organisations, and structured policies for the implementation, use and maintenance of AMTs are needed. This study identified additional risk factors regarding individual competencies in the use of AMTs at home. Employees at the tactical level seem to be more positive about the patient safety culture with AMTs in their organisations than nurses at the operational level are
Visualizing value creation and value capture beyond the buyer-supplier relation
No full textWhile societal challenges can best be solved when buyers and suppliers collaborate, this does not indicate that each actor also strives for the same values. Our study aims at visualizing values across buyers, suppliers and other stakeholders that are involved in a Dutch dike enforcement project. The findings show how value creation and capture is perceived differently by actors and that certain values seem to be captured by the ecosystem instead of the organizations directly involved in the buyer-supplier relation. This indicates that value visualisation contributes to explicating systemic business relations that develop around a single buyer-supplier relation
Ceci n’est pas une porte – This is not a door / Designs for a Cooler Planet
No full textIn Finland, construction generates 1.4 million tonnes of waste every year. Demolishing buildings is often presented as inevitable—justified by saying a building has ‘reached the end of its life’, like a food product that’s expired and can only be thrown away. At the same time, the regulations and practices guiding construction frequently encourage or even force unnecessary renovation or rebuilding, even when existing structures are still perfectly usable.Ceci n’est pas une porte – absurd stories about the challenges of recycling building components is the culmination of the Rakennuskato (Construction Loss) research project. It exposes the unnecessary demolition and repair that takes place in the construction industry—and the massive waste of natural resources it causes. Finland remains far from meeting the EU’s Waste Framework Directive target of a 70% recycling rate for construction waste.The researchers aim to awaken both citizens and policymakers to ask: Why are our ideals and policy goals so disconnected from the day-to-day realities of the construction industry? And how can we demand—and enact—real change?‘In construction, even the smallest streams add up to a powerful current. Maintaining and repairing existing buildings should always be the first option. And if that’s not possible, the building components and materials must be reused,’ says Laura Berger, Research Fellow at Aalto University.<br/