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On diffusion-controlled Li-trapping in high energy Li-ion cells under fast discharge and freezing conditions
No full textLi-ion batteries are promising energy storage devices owing to their high energy density which enables their use in different applications. Herein, we report on the electrochemical behavior of commercial high capacity 30 Ah pouch cells with energy density 275 Wh kg−1 over a wide temperature range (60 °C to −20 °C) using different discharging rates. A testing protocol was designed to understand the losses seen in discharge capacities (reduction charges) when the cells were discharged at fast rates (~16 % and 20 % capacity losses at discharge rates of 2C and 3C, respectively) or operated under freezing conditions (~17 % capacity loss at ~ −20 °C and C/5 discharge rate). The protocol involved monitoring the charge capacity (oxidation charge) before and after discharging as well as tracking the changes in open circuit voltage (OCV) for about 30 min after discharging. The accessible capacity was concluded to be limited not only by the developed iR-drop, but also by the diffusion-controlled lithium trapping as a result of the formation of concentration gradient of Li-ions. Notably, the surface temperatures of the cells were raised from 25 °C (environmental chamber temperature) to ~40 °C and 52 °C upon fast discharge at rates of 2C and 3C, respectively. Resting the cells for about 30 min after fast discharge was sufficient to drop the surface temperature back to 25 °C. This work provides insights for understanding the limitations of fast discharge and operating temperatures on industry relevant high energy Li-ion battery cells.</p
Characterization of a precipitate sludge from a sulfuric acid plant
No full textMaterials characterization is essential for both waste management, but also as the first stage in determining the potential for waste reprocessing as part of the circular economy. This paper describes in detail the multi-method characterisation of a filter press sulfur sludge sample from Boliden’s Harjavalta Smelter in Finland. This material represents the filter press cake precipitate after it has been clarified and filtered from the sulfuric acid plant. The sample was characterized geochemically and mineralogically, as well as for Acid Mine Drainage (AMD) potential. Magnetic and gravity separation process tests were also conducted to further investigate processing options for extracting any valuable metals. The study showed the sludge is chemically highly complex and mineralogically/materially challenging, mainly because of its extreme composition. In conclusion, it is suggested that a hydrometallurgical process path to neutralize this sample is the best way forward, which will be developed in future work.</p
Machine-learning integrated multi-domain co-optimization for electrified heavy duty fleets
No full textDriven by global regulations and the urgent need for a sustainable transition to zero-emission fleets in the transport sector, revolutionizing powertrain systems and their respective development processes have become more and more prevalent. Ambitious goals have been established for the latest public-funded research projects, such as ESCALATE (Powering European Union Net Zero Future by Escalating Zero Emission Heavy Duty Vehicles (HDV) and Logistic Intelligence), to increase the efficiency of the powertrain by up to 10% and thus maximize the operational range above 750 km. All of this will be achieved by introducing cost-effective, modular, and scalable electric powertrain components combined with advanced system control algorithms, targeting a broad market coverage with flexible vehicle architectures. In this context, the paper presents a completely virtual frontloading strategy to create a modular and highly integrated e-Axle system, leveraging a dual permanent magnet synchronous machine configuration to improve multiple performance indicators. These are the performance output, in terms of power and torque, system efficiency, and noise-vibration-harshness (NVH) criteria. To allow for an holistic system parametrization, a combined electric machine and transmission synthesis, using an active learning-based, multi-layer nested optimization approach together with a model predictive control strategy for motion and thermal domain has been employed. This development framework is integrating electric machine dimensions and transmission gear ratios as design parameters, as well as thermal actuation and torque as control parameters, to ensure a system right-sizing in a given use-case environment. By including monetary considerations with genetic algorithms, an extension for a powertrain family identification to a complete HDV fleet is facilitated. To demonstrate the feasibility of this framework, a concept assessment and validation has been carried out. The key achievements include a close matching of the defined KPIs, namely the peak wheel torque of 56150 Nm and continuous power of 381 kW – about 2%, respectively 0.2% above the target – and an enhanced peak power capability of 536 kW. In terms of energy efficiency, the multi-stage gear boxes support a well optimized operation in the VECTO long haul cycle, indicating a 40-ton vehicle energy consumption of around 109.7 kWh per 100 km, while the 76-ton variant consumes approximately 204.6 kWh per 100 km. Further the predictive cruise control strategy led to a consumption reduction of about 2.6%–3.4%.</p
Large Eddy Simulation of environmental impacts on mass transport in laboratory-scale vertical farm
No full textThe impact of environmental factors on airflow and mass transport within a laboratory-scale vertical farm is investigated using Computational Fluid Dynamics. Large Eddy Simulation models complex airflow behaviour, while solving enthalpy and mass transport equations yields temperature, humidity, and CO2 concentration. The Eulerian-Lagrangian approach simulates the free-fall of water droplets in the dehumidifier-cooling system. Humidity and CO2 consumption/production by plants and utilities are modelled as volumetric sources/sinks. An experimental campaign is conducted to measure temperature, relative humidity, and CO2 above cultivation beds, validating the numerical setup with mean absolute errors of 0.8%, 2.2%, and 3.9%, respectively. Analysing the airflow shows that the free fall of droplets is the dominant mechanism driving airflow characteristics. We investigate the effects of wall confinement, number of lamps, and location of lamps on the mass transport. Curtains were used to divide each cultivation bed into three regions to assess the wall confinement effect. Results show the overall adverse effect of curtains on mass transport. In more detail, mass transport is enhanced when the curtains and streamlines are aligned parallel, whereas it is reduced when they are perpendicular. Increasing the number of operative lamps improves the uniformity of mass distribution on the upper cultivation beds due to a stronger positive buoyancy. Positioning lamp-induced buoyant flow within the droplet’s lateral momentum injection zone further enhances vertical mass transport. These findings highlight the impact of environmental factors on mass transport, offering insights for more efficient designs of indoor vertical farms.</p
Islands of innovation:A Comparative Reflection on Industrial Policy, Access to Talent, and Technology Sovereignty
No full textFinland and Taiwan, though geographically distant, share the challenges of small, open economies reliant on global trade, talent, and energy. Taiwan’s targeted investments in critical technologies like semiconductors and AI, its institutional clarity, and agile governance offer a useful mirror for Finland’s broader but less output-focused innovation strategy. Facing similar demographic shifts, Taiwan has also moved decisively to attract international talent and reconfigure its higher education system, an area where Finland lags in reform.This brief aims to offer discussion points by sharing key lessons from Taiwan across six domains: critical technologies, industrial policy, talent, energy, regional renewal, and the role of research organizations. Kaohsiung’s industrial transformation, ITRI’s mission-driven role, and Taiwan’s approach to aligning tech ambition with systemic readiness provide practical insights for Finnish policymakers and innovation leaders. In short, Taiwan demonstrates how strategic focus, systemic coordination, and measurable outcomes can accelerate innovation capacity building. For Finland, adopting a more output-focused, resilient, and ecosystem-driven approach may be essential to sustaining competitiveness in a volatile global landscape
Futures of Everyday Life:A Qualitative Content Analysis of Future Personas in Scenarios
No full textScenario reports, holding a long-standing tradition in foresight and futures studies, act as an essential document for organizations to prepare for possible, plausible, and alternative futures. Focusing on descriptions and representations of everyday life, we examined 29 future persona narratives from six publications—covering a wide field from public to private sector—through qualitative content analysis. Our guiding question is: How can anthropological perspectives such as cultural relativism or postcolonial discourses contribute to an in-depth, qualitative interpretation depictions of future everyday life? Acknowledging anthropology's colonial origins and its growing commitment to the interests of indigenous and other marginalized groups, we offer alternative readings of prominent scenario reports. Our findings suggest that scenario reports, in addition to anticipating possible futures, construct certain futures based on a systematic analysis of empirical data but also speculative interpretation. The results of these interpretative acts often appear elitist, stereotypical, and technocratic, often replicating dominant societal narratives rather than fostering substantive shifts in how the future is imagined. We therefore call for a more polyphonic representation of futures in scenario writing and foresight work that can produce more discontinuous and transformative images of the future. We understand polyphonic representations as coined by various independent, predominant as well as subaltern perspectives on the same issue at stake while being offered the same amount of space. Therefore, as we will indicate in our analysis, most of the reports referred to are rather monophonic and do not offer discuptive perspectives on the future of everyday life. As an avenue of methodological development, we propose a more nuanced and comprehensive perception of culture and social structures in scenario narrative writing. In addition, ethnographic methods could increase our understanding of how futures are collaboratively constructed and produced by different actors and their respective backgrounds and knowledge in scenario processes.</p
Exploring reference standards for the measurement of respiratory rate in children under 5 years of age:a scoping review
No full textBackground Respiratory rate is an important part of assessing the clinical state of children, and various methods exist to measure it. However, there is a lack of a universally accepted reference standard to validate the performance of these methods. Aim To identify different reference standards that have been used to evaluate respiratory rate measurement methods in children under 5 years of age and describe their perceived strengths and limitations. Methods MEDLINE and Web of Science were searched for studies in English. Studies of children under 5 years of age, published between 2013 and 2024, in which a method for measuring respiratory rate was compared against a reference standard, were included. Deductive content analysis was used to map perceived strengths and limitations of each standard, and a forest plot analysis was used to compare agreement between the reference standard and the index tests. Results From 992 retrieved studies, 56 were included. The most common reference standard was impedance pneumography (22/56), primarily used in high-income settings, followed by manual counting (19/56), mostly employed in low- and middle-income settings, and capnography (9/56). Child age, clinical condition, setting, training of personnel and the ease of implementation were all important factors in which the reference standard was used and how it performed. Conclusion Three different reference standards were used for most studies; however, their relative performance to each other is unclear. There is a need for research that directly compares the performance of these reference standards across different age strata and settings in order to confidently recommend a reference standard for respiratory rate measurement methods.</p
Discrete acceleration-level pseudoinverse-free zeroing neurodynamics for robotic manipulator path tracking control
No full textPredicting the unknown next-instant state of the future nonlinear equation system (FNES) is critical for high-performance robotic manipulator path tracking control. While various algorithms have been developed to solve the FNES problem, many existing methods often focus on velocity-level solutions and rely on computationally expensive Jacobian matrix pseudoinverse operation, which impair both efficiency and accuracy. To bridge the gap, this paper proposes an innovative discrete acceleration-level pseudoinverse-free zeroing neurodynamics (DALPFZN) algorithm. By reformulating the FNES problem as a future nonlinear output-zeroing problem and operating at the acceleration level, the proposed algorithm effectively avoids the need for complicated pseudoinverse computation. Theoretical analyses show the convergence and stability of the DALPFZN algorithm. Numerical comparisons illustrate its superior efficiency and accuracy against existing methods. Furthermore, experimental results on MATLAB and CoppeliaSim platforms substantiate the effectiveness and outstanding performance of the DALPFZN algorithm. When the proposed DALPFZN algorithm is applied to the robotic manipulator path tracking control, the mean of the maximum steady-state output errors (MSSOEs) is 0.05 mm, and the mean of the average computing time per updating (ACTPUs) is 0.1 ms. Compared with the velocity-level pseudoinverse algorithm, the performance improvement rate of the ACTPU is 8.96%. Compared with the velocity-level pseudoinverse-free algorithm, the performance improvement rate of the MSSOE is 87.65%.</p
