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Beyond human proxies: The roles and usefulness of large language models in user research for mobility service development
No full textUser research is an integral part of mobility service development. However, user research is resource-intensive, including the effort required to recruit participants, and facilitate data collection procedures. Consequently, large language models (LLM) have been applied in the domain, building on the notion of LLMs being able to provide human-like outputs and thus simulate human users. Despite the increasing interest, guidelines for LLM implementation in user research processes and for evaluating the usefulness of LLM incorporation remain scarce, hindering researchers and practitioners from leveraging them effectively. Therefore, with the aim of providing a structured understanding of LLM integration, we delineate four main roles LLMs can play in user research (i.e., replace, complement, improve, research), along with three facets (i.e., realism, novelty, effort) for evaluating their usefulness. Combining the roles and usefulness facets, we introduce a framework for how LLMs could be used and what are the conditions for realizing their benefits. Additionally, we describe a hypothetical user research path, applying the approach to the development of new mobility services. The framework presents how and why LLMs could be used in various user research stages, providing a structured lens that aids researchers and practitioners to critically consider when and how to incorporate LLMs, and to evaluate LLM output usefulness, while considering the risks for doing so from the perspective of successful service design. By adopting a pragmatic and critical approach, the paper contributes to research on mobility, as well as more broadly on the use of synthetic participants in design praxis.</p
Processing and performance of HVAF-sprayed Fe-based bulk metallic glass coatings:A sustainable alternative
No full textBulk metallic glasses (BMGs) are increasingly recognized as promising materials for surface engineering due to their exceptional hardness, corrosion resistance, and wear resistance, which are critical attributes for components operating in harsh environments. Fe-based BMGs offer a sustainable alternative to conventional coatings that often rely on toxic or scarce raw materials, thus aligning with global environmental and regulatory objectives. This study focuses on a newly developed Fe-based BMG alloy with enhanced glass-forming ability and processability for thermal spray applications. While BMGs exhibit outstanding properties, their limited ductility poses significant processing challenges, including propensity to cracking during deposition. To overcome this, the feasibility of producing dense Fe-based BMG coatings using High Velocity Air Fuel (HVAF) spraying was examined, aiming for superior wear and corrosion resistance. Initial trials resulted in coatings with severe cracking, delamination, and poor adhesion. However, systematic manipulation of spray parameters led to coatings with markedly reduced cracking, improved adhesion, and enhanced microstructural integrity. Comprehensive characterization included microstructure, amorphicity, and hardness examination, complemented by wear and corrosion performance assessments. The promising results represent a critical step toward establishing Fe-based BMGs as viable and environmentally friendly coating solutions via HVAF thermal spraying.</p
Assessment of soil impacts from lead release by lead-halide perovskite solar cells based on outdoor leaching tests
No full textPerovskite solar cells represent a promising technology in the photovoltaic industry due to their high power conversion efficiency, potential for cost-effective manufacturing and versatile applications. The most stable and efficient perovskites to date rely on lead (Pb), raising concerns about leaching into the environment; however Pb release so far has only been quantified under laboratory conditions, and no field-based assessment under real outdoor expsosure has yet evaluated this risk. The present study quantified Pb leaching from various metal-halide perovskite compositions, device stacks and encapsulation approaches in a rooftop installation for up to 9 months. Pb leaching was low across all tested configurations, even in intentionally damaged materials. Glass–glass encapsulated tandem devices shattered by hail and plastic-encapsulated samples damaged by 100 µm pinholes released only 0.07% ± 0.01% and 0.15% ± 0.14% of their initial Pb, respectively, likely due to the slow diffusion of Pb cations in water. The highest leaching (4.81% ± 0.02%) occurred in unlaminated laboratory devices, demonstrating the importance of proper lamination. A self-developed freeware web tool was used to calculate predicted soil concentrations and evaluate potential impacts. Even for unlaminated devices, concentrations would only slightly exceed natural background levels (5.6 mg kg−1 increase), with negligible effects on soil fertility. A hypothetical worst-case scenario assuming a 1000 nm thick perovskite layer and complete Pb leaching onto a narrow strip of soil predicted a negative impact on soil fertility; however remediation would still not be required under Swiss environmental regulations. Overall, current industry-standard encapsulation limits Pb leaching to levels that almost completely mitigate negative impacts on soil health.</p
A Scots pine 4-coumarate:CoA ligase with high cinnamic acid affinity is the primary candidate for pinosylvin biosynthesis
No full textPinosylvin and its derivatives are defense-related stilbenoids that contribute to pathogen and decay resistance of Scots pine (Pinus sylvestris L.) heartwood. While most enzymes in the pinosylvin biosynthesis pathway in Scots pine have been identified, the enzyme responsible for activating cinnamic acid to cinnamoyl-CoA, an essential precursor for pinosylvin biosynthesis, has remained unknown. In this study, we explored Scots pine transcriptomic data to observe the expression profiles of the 4-coumarate:CoA ligase (4CL) genes and produced the enzymes in Nicotiana benthamiana to assay their kinetic properties. We identified and characterized four 4CL isoforms, one of which (Ps4CL2) was both co-expressed with pinosylvin biosynthesis genes under stilbene-inducing conditions and exhibited an unusually high affinity for cinnamic acid surpassing that of previously characterized cinnamate-activating 4CLs. Through site-directed mutagenesis and domain-swapping experiments with the closely related Ps4CL3, we showed that substrate preference in Ps4CL2 results from multiple interacting regions within the enzyme. Our findings establish Ps4CL2 as the prime candidate for cinnamate activation as the last missing enzyme for pinosylvin biosynthesis in Scots pine and provide insight into enzyme specialization within the 4CL family.</p
Measuring damage anisotropy in concrete from ultrasound velocity data
No full textThe uniaxial compression of an initially isotropic concrete specimen induces a damage pattern that is anisotropic: in the direction of loading, the concrete undergoes compaction, while in the directions orthogonal to the loading direction, concrete cracking can be observed. In order to quantify such damage patterns, one possibility is to observe the changes in the stiffness tensor of a compressed specimen with respect to the stiffness tensor of the corresponding virgin state specimen. The eigensolutions of the Kelvin–Christoffel matrix for anisotropic media provide the relation between ultrasound wave velocities in given wavefront and polarization directions and the stiffness matrix components. In this study, it is shown how using the through transmission method for the determination of first-time arrival, one can evaluate the sound wave velocities in different directions and compute the stiffness tensor components for a damaged concrete specimen. Plots of stiffness tensor components as a function of non-recoverable strain give a qualitative measure of the anisotropic strain degradation process
Large Language Models for Automated Data Access Policy Creation in Data Spaces
No full textData spaces are being developed to enable more standardized and secure data sharing. They provide a framework where data can be exchanged following predefined access control policies. However, manually defining machine-readable policies can be a time-consuming and error-prone task. It poses challenges for the adoption and scalability of Data Spaces. In this paper, we investigate the automatic creation of machine-readable data access policies that could support users of Data Spaces. We assess the ability of Large Language Models to generate structured data access policies and validate their adherence to the defined ontology. Our findings reveal that while Large Language Models excel at producing syntactically valid policies (98% accuracy) and maintaining ontological compliance (90% accuracy), they fundamentally struggle with encoding complex logical relationships in access control rules, with only 1% of generated policies passing logical consistency validation, highlighting the continued necessity of human expertise in policy creation
Gaseous ozone treatment of wood:Effect of treatment conditions on the wood wettability and phenol-formaldehyde adhesive bonding strength
No full textFindings of an earlier study, “Improving Wood Surface Wettability through Gas-phase Ozone Treatment of Air-dry Wood,” demonstrated that the wood gas-phase ozone treatment enhances the wettability of wood by water, and thus potentially also the spread, absorption, and adhesion of water-based adhesives and coatings to the wood surfaces. This study extends that work by examining the effect of ozone treatment temperature and the wood moisture content on the wettability of ozone treated wood and bonding strength of phenol-formaldehyde (PF) adhesive. In the present study, both air-dry and wetted birch plywood and veneer were ozone-treated at 23 °C, 35 °C, and 55 °C for 10 and 30 minutes. The amount of reacted ozone increased with higher treatment temperature and with an increase in the wood moisture content. However, the reduction in the water contact angle was more pronounced for air-dry wood. Bonding tests showed that the ozone treatments substantially increased the PF adhesive bonding strength, and the bonding strength correlated negatively with the ozone-treated birch veneer water contact angle. The results suggest that both the treatment temperature and moisture content of the wood during the treatment influenced the ozone reactions with wood, and thus on wood wettability and PF adhesive bonding strength (192 / max. 200).<br/
High-Throughput Computational Screening, Non-Metallic Inclusion Analysis, and Microstructural Characterization of a Novel Medium Manganese Steel
No full textHigh-throughput computational screening (HTCS) based on CALPHAD (Calculation of Phase Diagram) was employed to investigate potential chemical compositions within the medium manganese steel family for achieving desired austenite stability and stacking fault energy (SFE). The primary objective was to identify optimal alloy compositions that balance the complex effects of various alloying elements on retained austenite fraction and related mechanical properties. Utilising TC-Python Thermo-Calc software coupled with a custom-developed algorithm, two optimised compositions were determined: 0.35C, 9Mn, 1Mo, 3Al, 1Si, 0.05Nb, 0.3V (alloy 353), and 0.35C, 9Mn, 1Mo, 3Al, 1Si, 0.1Nb (alloy 310) in wt.% to be the best fited composition to our selected criteria. The alloys were subsequently produced via open-air induction furnaces, and the microstructure was analysed after the hot forging condition. The initial multiphase as-cast structure, primarily composed of lath martensite, δ-ferrite (34 vol.%), and retained austenite (RA, 5–7 vol.%), experienced notable grain refinement. Forging reduced δ-ferrite grain sizes from 39 µm to 12 µm (alloy 310) and from 46 µm to 9 µm (alloy 353), accompanied by increased RA content (28 vol.% for alloy 310 and 46 vol.% for alloy 353) and reduced RA grain sizes (1.2 µm and 1.9 µm, respectively). Non-metallic inclusions (NMIs) were analysed using field emission scanning electron microscopy coupled with energy dispersive X-ray spectroscopy, classifying inclusions primarily as AlN, MnS, (Mo,Nb)C, or their combinations. No significant differences in inclusion types were observed, but forged samples displayed reduced inclusion sizes. In summary, the results showed that HTSC effectively identified optimal compositions with a high fraction of retained austenite.</p
Design–Build with a Development Phase: The Underlying Theory
No full textThis study focuses on a design–build (DB) procedure that exploits the related parties’ (preconstruction) collaboration to improve the economic efficiency of construction projects. It is called design–build with a development phase (DBd). In the procedure, the owner and the selected contractor continue the development of the project solution in cooperation, adhering to the principle of benefit sharing, which is enabled by preagreed rules and the benchmark solution, formed as a result of requirement-based price-inclusive contractor selection where technical design is not included in the proposal; the formation of the final contract is a two-stage process, and a new owner decision is needed to enter the realization phase. More precisely, this study aims to discover and formulate a theory that underlies the DBd procedure that is a heuristic construct of the procedure’s origin. For that, the DBd procedure was conceptualized by determining its key elements and their relationships, and by showing how a coherent whole is achieved by the elements’ mutual interoperability. Therefore, the study contributes to the body of knowledge by crystallizing the DBd concept and its rationality. Even more importantly, the study eventually establishes the novel DBd procedure by combining consistent theoretical and practical views considering the earlier success of DBd in trial projects
Combustion of cables used in nuclear power plants
No full textThe combustion and subsequent reactions of cables found in nuclear power plants are investigated, including chlorosulfonated cables (CSPE cables) and a Low-smoke zero-halogen cables (LSZH cables). In some cases, the cables are irradiated with 1MGy of gamma radiation before combustion. Iodine is added to the gas phase to investigate the potential formation of organic iodides. The combustion process can be followed online with the help of FTIR. The combustion of the CSPE cable mainly releases HCl, SO2 and CS2 and aliphatic hydrocarbons. If the cables are pre-irradiated, the species released are largely the same, but the releases are lower. The LSZH cable required higher temperatures to pyrolyze and gave significant releases of acetaldehyde. This cable was not irradiated. The addition of iodine results in the formation of methyl iodide (CH3I) for the LSZH cable at 450°C. CH3I also reacts with other organics released in the combustion, forming isopropanol. The same happens for the unirradiated CSPE cable, but to a much lower degree.</p