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Automated data transfer for digital twin applications : Two case studies
No full textDigital twins have been gaining an immense interest in various fields over the last decade. Bringing conventional process simulation models into (near) real time are thought to provide valuable insights for operators, decision makers, and stakeholders in many industries. The objective of this paper is to describe two methods for implementing digital twins at water resource recovery facilities and highlight and discuss their differences and preferable use situations, with focus on the automated data transfer from the real process. Case 1 uses a tailor-made infrastructure for automated data transfer between the facility and the digital twin. Case 2 uses edge computing for rapid automated data transfer. The data transfer lag from process to digital twin is low compared to the simulation frequency in both systems. The presented digital twin objectives can be achieved using either of the presented methods. The method of Case 1 is better suited for automatic recalibration of model parameters, although workarounds exist for the method in Case 2. The method of Case 2 is well suited for objectives such as soft sensors due to its integration with the SCADA system and low latency. The objective of the digital twin, and the required latency of the system, should guide the choice of method. Practitioner Points: Various methods can be used for automated data transfer between the physical system and a digital twin. Delays in the data transfer differ depending on implementation method. The digital twin objective determines the required simulation frequency. Implementation method should be chosen based on the required simulation frequency. Swedish Research Council Formas, Grant/Award Number:2020-00222;</p
Free open source communities sustainability : Does it make a difference in software quality?
No full textContext: Free and Open Source Software (FOSS) communities’ ability to stay viable and productive over time is pivotal for society as they maintain the building blocks that digital infrastructure, products, and services depend on. Sustainability may, however, be characterized from multiple aspects, and less is known how these aspects interplay and impact community outputs, and software quality specifically. Objective: This study, therefore, aims to empirically explore how the different aspects of FOSS sustainability impact software quality. Method: 16 sustainability metrics across four categories were sampled and applied to a set of 217 OSS projects sourced from the Apache Software Foundation Incubator program. The impact of a decline in the sustainability metrics was analyzed against eight software quality metrics using Bayesian data analysis, which incorporates probability distributions to represent the regression coefficients and intercepts. Results: Findings suggest that selected sustainability metrics do not significantly affect defect density or code coverage. However, a positive impact of community age was observed on specific code quality metrics, such as risk complexity, number of very large files, and code duplication percentage. Interestingly, findings show that even when communities are experiencing sustainability, certain code quality metrics are negatively impacted. Conclusion: Findings imply that code quality practices are not consistently linked to sustainability, and defect management and prevention may be prioritized over the former. Results suggest that growth, resulting in a more complex and large codebase, combined with a probable lack of understanding of code quality standards, may explain the degradation in certain aspects of code quality.
Cirkulärt omhändertagande av solcellspaneler och vindturbinblad för vindkraftverk
No full textI regleringsbrevet för 2023 fick Energimyndigheten i uppdrag av regeringen att utreda hur solcellspaneler och vindturbinblad till vindkraftverk i högre utsträckning ska kunna tas om hand på ett giftfritt och cirkulärt sätt i enlighet med avfallshierarkin. Redovisningen av detta regeringsuppdrag, rapporten Från avfall till resurs – Förslag för en mer cirkulär hantering av solcellspaneler och vindturbinblad, ER 2024:11, baseras på denna underlagsrapport som har tagits fram av forskningsinstitutet RISE på uppdrag av Energimyndigheten. Analyser, slutsatser och förslag/rekommendationer som framförs i rapporten är författarnas egna.En fortsatt utbyggnad av fossilfri elproduktion är av stor vikt för att vi ska kunna nå Sveriges energi- och klimatmål. För att utbyggnaden i sig ska vara hållbar är det viktigt att vi redan nu planerar för hur avfallet från dessa elproduktionsanläggningar ska förebyggas, minimeras och sedan hanteras.Det finns redan i dagsläget aktörer som har utvecklat och håller på att utveckla ett flertal olika lösningar för ökad cirkularitet. Dessa möjligheter kan tas tillvara och främjas genom regelbunden kartläggning och genom att arbeta gemensamt inom EU. Genom ett sådant arbete finns det också större möjligheter att etablera industriella värdekedjor i Sverige för hanteringen av avfallet från solcellspaneler och vindturbinblad.En cirkulär hantering av avfall ger ett betydligt mindre avtryck på miljön än det som en linjär hantering ger upphov till. Det är viktigt att de aktörer som tillhandahåller fossilfri elproduktion tar ansvar under hela livscykeln och att det finns goda förutsättningar för aktörerna att göra det.Rapporten har skrivits inom upphandling 2023-10006 </p
Life cycle assessment of a circular textile value chain : the case of a garment made from chemically recycled cotton
No full textPurpose: The textile industry faces major challenges in reducing environmental impacts along the whole value chain. The overall aim of this paper was to assess the potential environmental benefit of a circular textile value chain, by evaluating a garment partly made from a chemically recycled cellulose carbamate fibre. The cellulose carbamate technology is a novel technology that turns cotton-rich textile waste into a cotton-like regenerated fibre. Methods: Life cycle assessment was performed to evaluate the environmental impacts of a garment made from the chemically recycled fibre, considering the whole life cycle. The evaluation also considered that the garment was part of a take-back system, meaning that the garment is collected for recycling after consumer use and thereby helps in closing the loop of the circular textile value chain. The focus of the assessment was on climate impact, water scarcity impact and land use impact. Furthermore, sensitivity analyses were included to test parts of the European Commission’s product environmental footprint method, e.g. the impact of applying the circular footprint formula. Results and discussion: The results showed that using a recycled cellulose carbamate fibre over primary conventional cotton showed benefits in all considered environmental impact categories; compared to organic cotton, the benefits were also shown for the land use impact category; the cradle to gate processes were the main hotspots for the garment’s life cycle, meaning that using a recycled feedstock is not the only measure needed to reduce environmental burdens; the use phase, and in particular using the garment to its full life length, is crucial for mitigating the environmental impact per garment use; and methodological choices related to the use of recycled feedstock, and sending materials to recycling at end-of-life, affect the outcome of the study. Conclusions: Selecting a chemically recycled cellulose carbamate fibre over primary fibres showed environmental benefits for the evaluated garment, but there are however trade-offs between different environmental impact categories and fibre types. Furthermore, using recycled fibres is one important step in reducing the environmental concerns of garments, but it is important to also make improvements along the whole textile value chain. Open access funding provided by RISE Research Institutes of Sweden. This work was supported by the European Union\u2019s Horizon 2020 research and innovation programme under grant agreement no. 101000559.</p
SKJUVHÅLLFASTHET HOS NATURLIGA BERGSSPRICKOR – MOT EN METODIK FÖR BESTÄMNING BASERAT PÅ DATA I FÄLT
No full textAtt kunna prediktera en bergssprickas skjuvhållfasthet är svårt i de fall där hela sprickytan inte är tillgänglig, såsom exempelvis en bergsspricka belägen under en befintlig betongdamm eller i projekteringsskedet för en tunnel. Denna artikel presenterar en metodik som undersöker möjligheten att utnyttja information från uppmätt sprickvidd och sprickans råhet i 3D med optisk scanning i mindre storlek, såsom borrkärnor, för att därefter prediktera skjuvhållfastheten i större skalor. Den framtagna metodiken har verifierats med två storskaliga skjuvförsök genomförda i laboratorium med konstant normallast med sprickprover tagna vid Krångede kraftstation. Den främsta nyttan med denna metodik är att den kan utgöra en möjlig väg framåt för att prediktera skjuvhållfastheten för bergssprickor i fall där sprickytan inte är helt tillgänglig.The prediction of a rock joint’s peak shear strength becomes complex when its joint surfaces are not fully accessible, such as the rock foundation under an existing concrete dam or the design stage for a tunnel. This paper presents a methodology that investigates the possibility of using information from measured aperture and 3D roughness with optical scanning at smaller sizes, such us drill cores, to predict the peak shear strength of large natural, unfilled rock joints. The presented methodology has been tested in the laboratory under constant normal load conditions on two natural, unfilled rock joint samples obtained from existing rock joints in the foundation of the Krångede concrete dam. The main benefit of this approach is that it may enable the prediction of the peak shear strength in the field under conditions of difficult access
Uneven exposure of compressed natural gas (CNG) and hydrogen (H2) cylinders : Fire and extinguishment tests
No full textVehicles that are powered by gaseous fuel, e.g., compressed natural gas (CNG) or hydrogen (H2), may, in the event of fire, result in a jet flame from a thermally activated pressure relief device (TPRD), or a pressure vessel explosion. There have been a few incidents for CNG vehicles where the TPRD was unsuccessful to prevent a pressure vessel explosion in the event of fire, both nationally in Sweden and internationally. If the pressure vessel explosion would occur inside an enclosure such as a road tunnel, the resulting consequences are even more problematic. In 2019 the authors investigated the fire safety of CNG cylinders exposed to localized fires. One purpose of the tests conducted in 2021 reported in this paper is to investigate whether extinguishment with water, e.g., from a tunnel deluge system, may compromise the safety of vehicle gas cylinders in the event of fire. Steel cylinders handles the situation with localizde fire and/or cooling with water well. Composite tanks can rupture if the fire exposure degrades the composite material strength, and the TPRD is not sufficiently heated to activate, e.g., if the fire is localized or if the TPRD is being cooled by water, which prevents its activation.Jonatan Gehandler reports financial support was provided by Swedish Transport Administration and Tunnel Underground Safety Center (TUSC). If there are other authors, they declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.</p
The Limits of Calibration and the Possibility of Roles for Trustworthy AI
No full textWith increasing use of artificial intelligence (AI) in high-stakes contexts, a race for “trustworthy AI” is under way. However, Dorsch and Deroy (Philosophy & Technology 37, 62, 2024) recently argued that regardless of its feasibility, morally trustworthy AI is unnecessary: We should merely rely on rather than trust AI, and carefully calibrate our reliance using the reliability scores which are often available. This short commentary on Dorsch and Deroy engages with the claim that morally trustworthy AI is unnecessary and argues that since there are important limits to how good calibration based on reliability scores can be, some residual roles for trustworthy AI (if feasible) are still possible.
Enabling Data-sharing in Logistics through Open Data Ecosystems - A Literature Review
No full textBackground: Road transportation is one of the main sources of CO2 emissions. Making logistics more efficient, e.g., through co-loading freight transport, would reduce emissions. However, this requires the sharing of freight and routing data between actors in the logistics chain. Aim: This study aims to explore the literature on how Open Data Ecosystems (ODEs) can be applied to the logistics sector. The study focuses on ODE governance, the actors involved, and legal and quality aspects. Method: The literature review employed publication database search, snowball sampling, and selected governmental literature. Thematic analysis is carried out on the identified literature. Results: The results indicate how an ODE can be applied to the logistics sector, although primarily evident in public transport. For freight transport, literature refers to Horizontal Collaboration. The literature is consistent in terms of governance of the ODEs and Horizontal Collaboration where there is typically a need for a neutral actor to take on the role of a platform provider to promote trust and enable collaboration. Conclusions: We conclude that the two literature streams of ODEs and Horizontal Collaboration could be integrated and foster a more efficient logistics sector where data is shared among the involved actors. Our findings also indicate aspects underpinning the collaboration among actors.The research is funded by The Swedish Transport Administration in the Triple F program (Fossile FreeFreight), Project nr 2022.5.2.5.</p
Energy flexibility using thermal mass for Swedish single-family houses
No full textThis paper characterised the potential of energy flexibility in relation to building envelop properties, heat emitters and ventilation for the Swedish context. Simulation results indicated that the potential was higher for newer houses with floor heating and lower for older houses with radiators in winter. Older houses with different levels of insulation showed a similar ability of conserving heat due to different extents of heat losses from ventilation. A house with balanced ventilation tended to be over-ventilated especially if the house was not airtight. The flexibility was decreased with increasing outdoor temperatures, and it was higher in winter and lower in spring/autumn. The authors would like to gratefully appreciate Swedish Energy Agency for final support (Grant No. P2021-00223)</p
Low-NOx thermal plasma torches : A renewable heat source for the electrified process industry
No full textIndustrial thermal plasma torches can heat a gas up to 5000–20,000 K, i.e., well above the temperature needed to replace the heat generated from the combustion of traditional fossil fuels (e.g., coal, oil, and natural gas) in large-scale process industry furnaces producing construction materials (e.g., iron, steel, lime, and cement). However, there is a risk for significant NOx emissions when air or N2 are used as plasma-forming gas since the temperature somewhere in the furnace always will be higher compared to the threshold NOx formation temperature of ∼1800 K. Torch NOx forms inside the high temperature region of the plasma torch (>5000 K) when air is used as gas. Process NOx forms instead when the hot gas (when air or nitrogen is used as plasma forming gas) from the plasma torch mixes with process air downstream the torch. By analysing the complex chemistry of both the torch- and process NOx formation with thermodynamic equilibrium and one-dimensional chemical kinetic calculations it was shown that adding H2 to the plasma-forming N2 gas significantly reduces the NOx emissions with more than 90 %. Verifying experiments with air, pure N2, and mixtures of H2 and N2 as plasma-forming gas were performed in a laboratory scale insulated laboratory furnace with different pre-heating temperatures of process air (293, 673, and 1073 K) which the plasma gas mixes with downstream the torch. Depending on the pre-heating temperature the NOx emissions were between 12,000–14,000 mg NO2/MJfuel when air was used as plasma forming gas. Substantial NOx emission reduction occurs both when N2 replaces air, where the NOx emissions was in the span of 8000–11,500 mg NO2/MJfuel and furthermore when H2 was mixed into the N2 gas stream. For the highest degree of H2 mixing (28.6 vol-%), the NOx emissions were between 450–1700 mg NO2/MJfuel depending on the pre-heat temperature of the process air, i.e., a reduction of 88–96 % and 85–94 %, respectively when air or N2 was used as plasma forming gas. The measured NOx emissions are then of the same order of magnitude as would be expected from the combustion of traditional fuels (coal, oil, biomass and pure H2). Finally, by analysing the aerodynamics in an axisymmetric furnace with an experimentally validated computational fluid dynamics (CFD) model using reduced chemistry for the NOx formation (19 species and 70 reactions), further guidelines into the process of NOx reduction from thermal plasma torches are given. This work was conducted as part of the Hydrogen Breakthrough Ironmaking Technology (HYBRIT) research project RP1. The Swedish Energy Agency is acknowledged for financial support of HYRIT. HYBRIT is a joint initiative of SSAB, LKAB, and Vattenfall with the aim of developing the world’s first fossil-fuel-free ore-based steelmaking route. Sofia Nordqvist (LKAB/HYBRIT), Christian Fredriksson (LKAB), and Fredrik Normann (LKAB/Chalmers Technical University) are also acknowledged for their constructive suggestions</p