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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
Interface morphology and dislocation-mediated processes during rapid solidification of thin films
No full textRapid solidification experiments have, in recent years, revealed a wealth of new microstructural phenomena that suggest a strong connection between the kinetics of solidification and the crystalline structures that emerge as a result. In this work, we investigate the interplay between interface morphology and defect-mediated processes during rapid solidification conditions using a Phase Field Crystal (PFC) model, enabling us to simultaneously and efficiently explore the physics of solidification and elasto-plasticity in the formalism of a single-field theory. We predict that there are two mechanisms by which dislocations emitted directly from the solid–liquid interface induce orientation gradients as well as the formation of subgrain boundaries within a single solidifying cell. We relate these mechanisms to the morphology of the moving solid–liquid interface and identify a suitable control parameter in the PFC model with which we can go between said morphologies by effectively changing the relative strength of the capillary length and kinetic coefficients of the solid–liquid interface. Thus, we are able to provide mechanistic explanations for several microstructural features (with an emphasis on orientation gradients and subgrain boundaries) observed during the rapid solidification of pure materials. We also provide a simple explanation for the formation of “jagged” subgrain boundaries, which is consistent with our experimental observations in rapidly solidified samples of Aluminum, whose mechanisms have thus far been unknown.</p
Insights into microbial sampling of ultra-low biomass, ultra-deep, hypersaline fluids fluids in Otaniemi, Finland
No full textIn the efforts to find new, environmentally friendly means for district heat production, two ultra-deep production wells were drilled in Otaniemi, Finland, reaching depths of approximately 6 km. At this depth, the fluids are saline, reaching 200 g L-1 TDS, anoxic, approximately 100°C hot and experiencing a hydrostatic pressure of 500 bar. The fluids are slightly alkaline and oligotrophic but contain CH4 and H2. In an effort to study the microbiological composition of these fluids, samples were collected using a positive displacement sampler operated by ICDP’s Operational Support Group (OSG) in September, 2024. The sample volumes were ~600 mL/sample. The sampler was cleaned with 70% ethanol and rinsed with sterile MilliQ water. Contamination control samples were collected by filling the samplers with sterile water and collecting and treating the control sample in the same way as the actual samples. Contamination control samples were also collected from the water-glycol solution and mineral oil used for the sampler operation. The samples were studied by epifluorescence microscopy, DNA was extracted by first collecting the biomass on 0.1 m pore-size filters and the filtrate was additionally precipitated with PEG. The microbial communities were characterized by qPCR, amplicon sequencing and metagenomics. In addition, cultures targeting heterotrophic and autotrophic thermophiles were set up from all samples in anaerobic infusion bottles. The first results indicate that even low-level contamination from reagents, equipment and sample handling is detrimental to the study. The amount of indigenous microorganisms was < 5 bacterial 16S rRNA gene copies mL-1 measured from the 0.1 m pore-size filter DNA extraction, whereas the contamination control (MilliQ water) contained between 160 – 380 gene copies mL-1. The filtrate, i.e. <0.1 m sized cells, the copy numbers were 17 – 86 mL-1, whereas the MilliQ contamination control samples contained 15 – 21 bacterial 16S rRNA gene copies mL-1. Epifluorescence microscopy corroborated the results. Amplicon sequencing showed a high proportion of contamination from sampling equipment, sample handling and laboratory reagents. Stringent curation of the data by removing all typical human contaminants and all taxa present also in the contamination controls, revealed a bacterial community mostly consisting of members of the Patescibacteria phylum. These bacteria are ultra-small and are often found in deep groundwater environments. Our study is the first to show Patescibacteria as the dominating component of the community in ultra-deep, hot, saline fluids, although their numbers are low. Culture based and metagenomic analyses are ongoing to reveal the first clues to the metabolic capacities of this phylum. <br/
Digitalisation in geosciences for environmental protection
No full textData Science (Digitalization and Artificial Intelligence) became more than an important facilitator in various domains in fundamental and applied sciences as well as industry and is disrupting the way of research already to a large extent. Originally, data sciences were viewed to be well-suited, especially, for data-intensive applications such as image processing, pattern recognition, etc. In the recent past, particularly, data-driven and physics-inspired machine learning methods have been developed to an extent that they accelerate numerical simulations and became directly applied in the nuclear waste management cycle. In addition to process-based approaches for creating surrogate models, other disciplines such as virtual reality methods and high-performance computing are leveraging the potential of data sciences more and more. The present challenge is utilizing of the best experimental and monitoring data as well as model concepts and tools to integrate multi-chemical-physical, coupled processes, multi-scale and probabilistic simulations in Digital Twins (DT) able to mirror or predict the performance of its corresponding existing or future physical implementations including workflows. The call for the Topical Collection was initiated from different actors, including research entities, technical support organizations and nuclear waste management organizations of the European projects EURAD (European Joint Programme on Radioactive Waste Management) and PREDIS (Pre-disposal Management of Radioactive Waste). The Topical Collection attracted a large number of manuscripts, more than eighty of which were published. These articles reveal a strong academic focus on using machine learning to map and assess soil and groundwater resources, hydrology and land use, landslides, and climate protection. They also highlight the core theme of nuclear waste management.</p
Elemental analysis of divertor marker tiles exposed during the 2018 (C3), 2019 (C4) and 2020 (C5) WEST campaigns
No full textErosion marker tiles mounted in the lower divertor of WEST were exposed during Phase 1 of plasma operations to evaluate poloidal erosion and re-deposition profiles on the tiles. Previous analyses performed to the exposed tiles have shown distinct erosion- or deposition-dominated patterns on them. Afterwards, core-drilled disks cut from the tiles were sent to different laboratories for further and detailed analysis. The present work relates the main results achieved from five characteristic regions of the tiles after completion of the C3, C4, and C5 experimental campaigns on WEST. SIMS and complementary IBA measurements were carried out and the corresponding elemental depth profiles strongly agree, confirming the main earlier conclusions. Deposits are composed of 2H, B, C, O, Mo and W, mainly. Low amounts of Cr, Fe, Ni and Cu were identified as additional metallic impurities. The research confirmed the locations of thin deposition zones nearby the inner and outer divertor limits: at the inner region, the deposition of B and C is particularly enhanced after C4 and C5. Strong erosion zones are located at the inner and outer strike point (ISP and OSP, respectively) areas: only a small erosion occurred after C3, which evolved after C4; nevertheless, the deposition of B and C is enhanced at the OSP edge after C5 nearby the thin deposition zone. Thick deposits appear in the neighborhood of ISP, towards the high field side, and evolve significantly after C4. The amount of O follows the deposition of B. Low retained amounts of 2H were quantified.</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
Enabling cryogenic technologies for superconducting quantum devices
No full textLow-temperature refrigerators cool systems down to cryogenic temperatures near absolute zero, where thermal noise and decoherence are suppressed. This allows quantum phases, such as superconductivity, to emerge in certain materials and enables the harnessing of individual quantum states for scientific and high-performance applications. However, the refrigerators used for these purposes are large and rely on cryoliquids, such as scarce and expensive 3He, which can be a limiting factor depending on the technological application. To enable more scalable, costeffective cryogenic platforms, new refrigeration technologies must be developed. To this end, chip-scale coolers based on superconducting tunnel junctions have been envisioned to provide a fully solid-state alternative. Proof-of-principle operation of these coolers has been demonstrated at temperatures below 1.5 K, but to link them with commercially available 4He pulse tube cryocoolers, stage operating above 2.0 K is required. Additionally, thermally isolating and electrically conducting methods are needed to cascade coolers operating at different temperature ranges. In this thesis, the fundamental components of a multi-stage chip-scale cooler operating at temperatures compatible with 4He pulse tube cryocoolers are developed. A superconducting flipchip assembly fabricated with In-bumps was characterized in the sub-kelvin temperature range, and the inter-chip thermal resistance was found to be suitable for chip-scale cooling applications. A through-chip signal routing method utilizing ALD TiN-based TSVs was developed, and the demonstrated critical temperature of 2.0 K enables dissipationless DC transport for multi-chip assemblies, such as cascaded coolers. Additionally, ALD MoCx was shown to exhibit a superconducting transition temperature up to 4.4 K and high conformality, showing promise as a TSV-compatible material. The key achievement of electronic cooling of Al thin film from a bath temperature of 2.4 K down to 1.6 K was demonstrated using Nb-based superconducting tunnel junctions, probed by an onchip junction thermometer. Thermal model calculations highlighted the emergence of superconductivity in the Al beneath the cooler junctions, persisting up to a bath temperature of 2.4 K: one kelvin higher than the nominal critical temperature of the Al thin film. The single-stage cooler operating above 2.0 K enables solid-state on-chip cooling from 4He pulse-tube compatible temperature without the use of magnetic fields. Additionally, Al- and V-based tunnel junctions were fabricated at the wafer scale using degenerately doped Si as the normal electrode. The junctions exhibited suitable low-temperature electrical characteristics for cooling applications. From superconducting interconnects to tunnel-junction components supporting high cooling power density above 1 K, the achievements presented in this thesis enable modular design of chip-scale cascade coolers. This technology is envisioned to support the scaling of several superconducting quantum devices from proof-of-principle to multi-component systems beyond experimental lab environments
Inorganics from kraft black liquor enable rapid oxidative crosslinking and morphology control in lignin derived hard carbons
No full textThe conventional approach to converting kraft lignin (KL) into hard carbons is to start with highly purified, low-ash KL feedstocks and then rely on slow, energy-intensive oxidative stabilization and added crosslinkers to keep melting and foaming associated thermal challenges under control. Herein, we deliberately invert this paradigm. Instead of starting with highly purified KL, we retain pulping inorganics and use them as catalytic centers for oxidative crosslinking and melt suppression of KL. Spherical KL microparticles (KL-MP) were recovered from softwood black liquor by membrane filtration and spray-drying steps, intentionally retaining inorganic sodium (Na) salts as well as organically bound Na in KL-MP, and were compared to acid-precipitated, low-ash reference KL (KL-REF). During thermo-oxidative pretreatment (250 °C, 5 °C/min) in air, KL-MP undergoes inorganic-catalyzed rapid oxidative crosslinking that converts thermoplastic lignin into a rigid network, whereas KL-REF softens, foams, and fuses. Experimental analysis identifies organically bound Na-phenoxide type species as key catalytic sites. Proton magnetic resonance thermal analysis and molecular dynamics simulations reveal strongly reduced segmental mobility and Na-driven ionic clusters acting as physical crosslinking points. After pretreatment, inorganics are removed by a washing step, and the crosslinked KL-MP is carbonized, yielding low-surface-area hard carbons that retain their initial micron size and spherical morphology. As Li-ion battery anodes, the derived hard carbon shows better electrochemical performance than carbons derived from KL-REF. Overall, the work shows how otherwise undesirable inorganic impurities can simplify thermal conversion of KL, with potential for diverse applications where particle size and shape are critical
Exploring new cellular agriculture-based value chains via an analysis on potential feedstock sources in Finland
No full textThe aim of this study was to examine cellular agriculture-based value chains in Finland with two specific objectives: 1) to estimate the potential of selected Finnish agri-food industry side streams and agri-biomasses as the source of carbon for microbial protein production and 2) to identify the barriers and enabling factors related to four cellular agriculture-based value chains based on the Finnish feedstocks sources for fermentation. By evaluating the carbohydrate content of 13 plant-based biomass streams (molasses, brewers spent grain, distillers spent grain, sugar beet stalk, sugar beet pulp, oat husk, wheat bran, rapeseed cake, potato cell juice, potato peels and residues, potato tops, straw, surplus grass) as a sugar source for fermentation, the total microbial protein production potential was calculated annually at ca. 290 000 and 360 000 tons for precision and biomass fermentation, respectively. Among the agricultural and food industry streams, straw and oat husk biomass could theoretically supply feedstock for 211 000 and 22 000 tons of protein per year by biomass fermentation, respectively. This is a substantial amount, e.g. when considering 120 000 tons of protein needed annual by Finnish population. The qualitative part of the study elaborated barriers and opportunities of the biotechnology-based production processes using four value chain concepts with distinct feedstock source (grass, bran/husk, sawdust and greenhouse residues) as case examples. The qualitative analysis concluded that, in addition to bioprocess development for reducing production costs, key factors for ensuring well-functioning cellular agriculture business models include resolving agricultural feedstock pre-processing and logistics, optimized facility location, and access to renewable energy
From electricity to economy-wide Net-Zero:Comparative analysis of global energy pathways
No full textThe transition to Net Zero (NZ) energy systems has become a global priority for combating climate change and achieving sustainable energy systems. This paper presents a systematic review of national NZ electricity and energy system studies, with a primary focus on country-based modeling practices rather than purely academic literature. The review highlights how NZ pathways across nations reflect their unique energy resources, policy priorities, technological capabilities, and socio-economic contexts. Drawing from studies conducted after the Paris Agreement, the paper classifies NZ work into four categories: (I) clean electricity (CE) system studies, (II) NZ electricity system studies, (III) economy-wide NZ studies, and (IV) worldwide NZ economy studies. For each category, it examines the modeling frameworks used, the treatment of key technologies, and the integration of policy and market considerations. The analysis highlights significant differences in assumptions, time horizons, technology portfolios, and the treatment of grid reliability, flexibility, and seasonal balancing. By synthesizing results from multiple countries, including the United States, Japan, South Korea, China, the UK, Sweden, Thailand, France, Canada, Australia, Colombia, Indonesia, Vietnam, and EU member states, the paper identifies common challenges such as long-duration storage needs, transmission expansion, and operational stability under high inverter-based resource penetration. The findings reveal that while renewable energy and storage dominate most NZ strategies, achieving reliable and cost-effective transitions will require integrated planning across sectors, coordinated infrastructure investment, and context-specific policy design. This country-comparative perspective offers insights for policymakers, system planners, and researchers seeking to adapt global NZ strategies to national realities.</p