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Implementation of an improved low-resolution encoder-based speed and rotor flux estimation strategy for induction motors in the wide-speed range
No full textAn induction motor (IM) drive system with low-resolution encoders has to make a compromise between cost and performance, which is suitable for industrial electric vehicles, including electric forklifts, and electric lifts. However, the inaccurate and delayed position signals from low-resolution encoders lead to torque ripple and oscillations in rotational speed, especially in the low-speed range. To address these problems, this paper proposes an improved low-resolution encoder-based speed and rotor flux estimation strategy. The hybrid speed observer is designed to estimate the rotational speed smoothly and accurately. Meanwhile, an improved reduced-order flux observer with an adaptive gain is designed to meet the control performance requirement in the wide-speed range. The improved low-resolution encoder-based speed and rotor flux estimation strategy can meet the requirements of a high output torque at extremely low or zero speed, and full-power operation in the high-speed range. A 680 W IM test platform is built, and experimental results verify the effectiveness and correctness of the improved low-resolution encoder-based speed and rotor flux estimation strategy
Feasibility of dried blood spot collection for caffeine pharmacokinetic studies in microgravity: Insights from parabolic flight campaigns
Get PDFAims: Therapeutic drug monitoring for astronauts faces limitations in conventional blood sampling and sample management onboard the international space station. Here, we explore the feasibility of dried blood spot (DBS) collection during parabolic flights (PF) to overcome these constraints. Methods: We assessed the feasibility of blood deposition on blotting paper for preanalytical aspects in a PF using synthetic blood. Subsequently, DBS sampling validation was carried out in another PF campaign. Twenty volunteers participated in a pharmacokinetic study on caffeine and its metabolite, paraxanthine, conducted during parabolic flights. After >18 h caffeine washout, coffee (115 mg), tea (30 mg) or dark chocolate (11 mg) were ingested by the participants. DBS samples were collected at baseline, during weightlessness and post-flight. Caffeine and paraxanthine were analysed using liquid chromatography–tandem mass spectrometry (LC-MS/MS). Genotyping for cytochrome P450-1A2 (CYP1A2) was performed and a metabolic ratio by area under the curve for caffeine and paraxanthine (AUCPAX/AUCCAF) for CYP1A2 was determined. A user experience survey was also conducted. Results: Full in-flight pharmacokinetic study was feasible in seventeen volunteers with three unable to perform the sampling due to motion sickness. Nineteen participants (twelve males and seven females) completed pharmacokinetic profiles, with repeated pharmacokinetic studies for six participants. CYP1A2 genotyping resulted in eight ultrarapid, eleven intermediate, and one poor metabolizer. Among the women, four were on oestrogen contraceptives, a known inhibitor of CYP1A2, and were considered as poor metabolizers. Expected differences in kinetic profiles, consistent with consumption habits, the ingested dose and the genotypic/phenotypic information, were observed. The mean caffeine AUC for coffee, tea and chocolate were 9419ng.h.mL−1 (95% confidence interval [CI]: 6222–12 616, n = 10), 6917ng.h.mL−1 (95% CI: 2729–11 105), n = 7) and 3039ng.h.mL−1 (95% CI: 1614–4142, n = 12), respectively. The mean paraxanthine AUC were 10 566ng.h.mL−1 (95% CI: 6242–14 890, n = 10), 4011ng.h.mL−1 (95% CI: 2305–5716, n = 7) and 3638ng.h.mL−1 (95% CI: 1589–40 859, n = 12), respectively. The mean metabolic ratio in oestrogen-treated women was 0.53 (95% CI: 0.35–0.71) compared to 1.19 (95% CI: 0.99–1.33) in others. The mean metabolic ratio was 1.02 (95% CI: 0.81–1.23, n = 15) on the ground and 1.10 (95% CI: 0.70–1.41, n = 13) during the parabolic flights, with no significant difference observed between the two conditions. Overall participants were satisfied with the usability of the method. Conclusions: DBS collection was safe, stable, feasible and well accepted in weightlessness. This method would offer valuable insights into human metabolism adaptation during long-term spaceflight, addressing space pharmacology challenges
Mills and society in early medieval northern Italy
Get PDFDrawing on the extensive documentary record of northern Italy, available archaeological evidence, and comparative case studies from early medieval Europe, this study demonstrates that mill-based landscapes in the Po and Friuli-Venetian plains were shaped by society as a whole. Italian charters from the late ninth and tenth centuries highlight the pivotal role of kings and emperors in managing mills and milling resources, alongside ecclesiastical and secular landlords, aristocratic women, and wealthy peasants. This article explores the varied forms and functions of mills, highlighting that, beyond their crucial role in ecological sustainability, they also served as powerful social instruments for establishing authority, consolidating alliances, and controlling territory
Resilience improvement framework based on strategy optimization of power systems to typhoons
Get PDFTyphoons severely damage power systems and cause them to recover slowly. To improve the power systems resilience to typhoons, this paper first evaluates the operational states of components within power systems based on a typhoon wind-field model and infrastructure fragility curves. The network functional model was built using undirected weighted graphs and adjacency matrices. A quantitative resilience assessment of power systems was achieved through functional time-varying analysis. Subsequently, a resilience improvement framework based on strategy optimization in power systems was proposed. The framework includes two optimization algorithms and four strategies. A wind-resistant improvement strategy optimization algorithm was proposed based on economic constraints. A functional recovery strategy optimization algorithm was proposed under resource constraints. The recovery efficiency was increased by assessing the repair priority of infrastructure and resource utilization. The effectiveness and interrelationships of these strategies are evaluated based on resilience metrics. Taking a typical power-network reliability test system as a case study for resilience improvement strategies under typhoon disasters. The optimal combination of multi-dimensional strategies was determined based on economic budgets and resource constraints, thereby achieving maximum resilience improvement for power systems under various engineering scenarios and typhoon events
Evaluation of the properties of cardboard for power generation
Get PDFThis study presents the first comprehensive characterisation of post-consumer cardboard as a biomass fuel for power generation, with emphasis on its suitability for pulverised fuel and stoker furnace systems. Compared to eucalyptus, cardboard samples exhibited lower carbon content (38.2–39.3 % vs. 46.7 %), reduced higher heating values (15.9–16.5 MJ/kg vs. 21.0 MJ/kg), and significantly higher ash contents (8.9–10.6 % vs. 0.6 %). A novel thermogravimetric method was developed to quantify calcium carbonate content, revealing concentrations of 5.5 % in unprinted cardboard and up to 12.2 % in printed paperboard. Despite its lower energy density, cardboard chars exhibited favourable combustion characteristics, including a higher proportion of thin-walled and porous char morphologies, which are known to burn quickly. The study also investigated the impact of combustion on particle shape, identifying a potential correlation between sphericity and aspect ratio. This correlation, if validated, could simplify the estimation of three-dimensional sphericity for combustion modelling. Operational challenges were also identified, including the formation of low-density agglomerates during milling and elevated ash content, which may affect fuel handling and system compatibility. Overall, the findings support the integration of cardboard into the biomass fuel mix, contributing to fuel diversification and energy resilience in the transition to low-carbon power systems. Further research on ash fusion behaviour, emissions profiling, and large-scale combustion trials is recommended to confirm its industrial applicability
Comparing peripheral limb and forehead vital sign monitoring in newborn infants at birth
Get PDFBackgroundTo study the feasibility of measuring heart rate (HR) and oxygen saturation (SpO2) on the forehead, during newborn transition at birth, and to compare these measurements with those obtained from the wrist.MethodsVital signs were measured and compared between forehead-mounted reflectance (remittance) photoplethysmography sensor (fhPPG) and a wrist-mounted pulse oximeter sensor (wrPO), from 20 enrolled term newborns born via elective caesarean section, during the first 10 min of life.ResultsFrom the datasets available (n = 13), the median (IQR) sensor placement times for fhPPG, ECG and wrPO were 129 (70) s, 143 (68) s, and 159 (76) s, respectively, with data recorded for up to 10 min after birth. The success rate (percentage of total possible HR values reported once sited) of fhPPG (median = 100%) was higher compared to wrPO (median = 69%) during the first 6 min of life (P 95% agreement by 3 (fhPPG) and 4 (wrPO) min. SpO2 for fhPPG correlated with wrPO (r = 0.88), but there were significant differences in SpO2 between the two devices between 3 and 8 min (P < 0.005), with less variance observed with fhPPG SpO2.ConclusionIn the period of newborn transition at birth in healthy term infants, forehead measurement of vital signs was feasible and exhibited greater HR accuracy and higher estimated SpO2 values compared to wrist-sited pulse oximetry. Further investigation of forehead monitoring based on the potential benefits over peripheral monitoring is warranted.ImpactThis study demonstrates the feasibility of continuously monitoring heart rate and oxygen saturation from an infant’s forehead in the delivery room immediately after birth.Significantly higher SpO2 measurements were observed from the forehead than the wrist during the transition from foetal to newborn life.Continuous monitoring of vital signs from the forehead could become a valuable tool to improve the delivery of optimal care provided for newborns at birth
Shelf-inflicted head injuries
No full textPurposeTo evaluate the diagnostic yield of cranial computed tomography (CT) imaging in patients who sustained minor head trauma after directly hitting their head on a shelf or cupboard, without an associated fall. The study aimed to assess whether such low-impact mechanisms warrant cranial imaging. MethodsThis was a retrospective observational study conducted at the emergency department of a major trauma centre in the United Kingdom. Data were extracted from the institutional Radiology Information System and electronic health records, covering the period from June 2006 to April 2025. An initial cohort of 320 patients referred for CT head imaging was identified using a keyword-based search of radiology request histories. Of these, 109 patients were included based on a clearly documented mechanism of injury involving impact with a cupboard or shelf, without an associated fall. Exclusion criteria included alternative mechanisms such as falls, falling objects, assault, or irrelevant mentions. The primary outcome was the presence of acute intracranial pathology on CT head. Secondary data collected included age, sex, injury mechanism, clinical symptoms, adherence to National Institute for Health and Care Excellence (NICE) head injury imaging criteria, and any scalp or skull findings. ResultsOf the 109 included patients, median age was 48 (31-66), females 76 (70%). Eight patients (7%) had scalp findings, including swelling or laceration. Despite the low-force mechanism, 79 patients (72%) met at least one NICE guideline criterion for imaging, most commonly due to vomiting or anticoagulant use. None demonstrated acute intracranial pathology or skull fracture on the CT head scan. The absence of positive findings suggests that careful vetting of NICE criteria in the context of biomechanically implausible mechanisms may reduce unnecessary imaging. ConclusionWalking into or standing up and hitting a shelf or cupboard is an insufficient force to generate clinically significant traumatic brain injury. Direct head impact from a fixed object, without an associated fall, appears to be a biomechanically low-risk mechanism. This study supports a more scrutinised and context-aware application of the NICE head injury criteria in such scenarios, to help rationalise imaging demand, optimise resource use, and reduce unnecessary exposure to ionising radiation
Diabetes and technology – an update for the general physician
Get PDFDiabetes is a growing public health concern. Approximately 20% of acute NHS hospital beds are occupied by individuals with diabetes. Following the recent NICE (National Institute for Health and Care Excellence) updates, diabetes technologies are increasingly available in the NHS. Despite the benefits, they present challenges, eg unfamiliarity, insufficient education, and lack of confidence of general physicians who are increasingly likely to encounter people using these technologies, presenting with acute illnesses. This review aims to update the general physicians with diabetes technologies such as continuous glucose monitors, insulin pumps, hybrid closed loop systems and how to troubleshoot in acute illnesses, diabetes emergencies, perioperative management and radiological investigations. While it is important to develop consistent inpatient care pathways and out-of-hours support from diabetes teams, it is vital to enhance the knowledge and confidence of non-diabetes physicians. Further research is warranted to support the use of technology in inpatient settings and diabetes emergencies
Bioleaching: from natural ores to urban mines for sustainability, circularity, and carbon neutrality
Get PDFSecuring critical raw materials for net-zero energy systems and green technologies, has become a global priority. This urgency is fuelled by increasing demand, dwindling natural reserves, and rising geopolitical instabilities. Urban waste streams, often rich in metal concentrations than natural ores, are emerging as viable alternative for metal recovery. Bioleaching, a natural process utilising microorganism to mobilise metals from solid mineral matrices, has become increasingly popular as a sustainable and economically attractive alternative to conventional mining of minerals, particularly for low-grade ores and waste-derived feedstocks. The attractiveness of bioleaching lies in low environmental impact and high efficiency, even at low metal concentrations. This review explores different metal-bearing secondary materials containing critical, precious, and rare earth elements (REEs) as potential feedstocks for bioleaching. It traces the evolution of bioleaching from natural ore processing to its growing utility in urban waste valorisation within a circular economy framework. It compares bioleaching process in natural ores versus urban waste, while showcasing recent advancements toward commercial implementation. The review also identifies existing challenges and proposes strategies for improvement. Finally, it articulates bioleaching's potential for integration into a circular economy model, emphasising its role in enabling sustainable metal recovery and achieving carbon neutrality goals
Teleoperated astropharmaceutical payload for long-duration space missions: Project VITA!
No full textThe VITA (Visualising In-space Tx-Tl Astropharmaceuticals) mission is a teleoperated Astropharmaceutical cube-payload that is aiming to launch a biological experiment to the ICE Cubes Facility (ICF) on board the International Space Station (ISS). Project VITA aims to enable on-site, on-demand production of therapeutics for long-duration human spaceflight, addressing the critical need for transportable medicines as outlined by the International Space Exploration Coordination Group (ISECG) Global Exploration Roadmap (GER). The main scientific goal is to demonstrate efficient and effective cell-free synthesis in a compact and flexible platform. Considering the possible increase in future human spaceflight missions to the Moon and Mars, the success of VITA will be a turning point to further satisfy the demand for medical drugs during long duration missions. Following weeks of preservation, the experiment intends to demonstrate the ability to rehydrate the freeze-dried cellulose stacks, kickstarting the synthesis of fluorescent proteins, and perform real-time, in situ detection through fluorescence spectroscopy and imaging. The aim of this paper is to present the system architecture required for teleoperated Astropharmaceutical experiment cubes and CubeSats, covering merits and drawbacks. Considering the potential large variation of temperature in a spaceflight mission, and the critical temperature dependency to maintain protein stability, this paper also presents studies carried out and outcomes for active and autonomous thermal management systems. A key innovation of the mission is the implementation of a miniaturised, dual-mode thermal control system using Peltier modules and a predictive two-way control algorithm, enabling precise and autonomous temperature regulation within strict power constraints. Since this will be just a first step for in space pharmaceutical production, it will open a new broad subject and the final part will focus on future work areas to improve the project for possible Astropharmaceutical production platforms beyond Low Earth Orbit (LEO). Knowing that one of the biggest challenges for human spaceflight is related to human health and reflecting the limited access to Earth, the medical challenges must be overcome, and in-situ therapeutic production shall be proved. Hence, the initial success of the VITA mission will be a pioneering step to enable deep space human missions
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