RISE – Research Institutes of Sweden
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A Guide to Data Quality Testing for AI Applications based on Standards
No full textData quality testing is critical for the development and deployment of Artificial Intelligence (AI) systems, particularly those used in decision-making processes. The integrity, accuracy, and reliability of data directly influence the performance and fairness of AI systems. Ensuring high-quality data is crucial as it not only helps in reducing biases but also in enhancing the overall effectiveness and trustworthiness of AI applications across various domains. This report provides a detailed exploration of the necessary prerequisites for effective data quality testing, including the identification of key data attributes and the establishment of specific quality benchmarks. It discusses various data quality characteristics and metrics for assessing and improving the quality of data used in AI systems. In particular, the report discusses the relevant standards and guidelines that govern data quality testing, offering a structured framework for organizations to adhere to these practices. By implementing rigorous data quality testing protocols, organizations can significantly mitigate risks associated with data-driven decisions, thereby ensuring that their AI systems operate within the desired scope of accuracy and fairness. This not only aligns with regulatory compliance but also enhances the credibility and reliability of AI applications in real-world scenarios
A Holistic and Circular Approach for Managing End-of-Service Wind Turbine Blades
No full textThis paper aims to define the challenges and requirements necessary for the holistic management of wind turbine blades at the end of their service (EoS). Conducted within the Swedish research project Circublade, this study focuses on Sweden, although many challenges and findings are applicable to other countries. Various alternatives for managing EoS wind turbine blades exist at different levels of market maturity, but this paper specifically focuses on repurposing the blades into new products. The development of three concept designs—short-span pedestrian bridges, façade elements for building applications, and noise barriers for roads and railways—has been explored, along with aspects related to material sourcing, logistics, and implementation. For material sourcing, a digital platform containing blade data and tools to facilitate repurposing has been developed. An environmental evaluation of the different concepts highlights the significant impact of transportation on the overall environmental footprint, underscoring the necessity of a holistic approach to managing EoS blades.This research was funded by the Swedish Innovation Agency VINNOVA, grant number 2022-01348.</p
Circular product design for allowing re-using and re-purposing of products and components : a conceptual framework for circularity
No full textWe live in a fast-consuming era, where manufacturers producing products faster than ever and with only one lifecyle in mind. This phenomena has resulted in products being designed and manufactured with attention to the company profit and insufficient attention to the implementation of circular approached and by extent sustainability. Currently, the implementation of circularity is only considered at the end of the life of a product and not from the beginning during the design of the product. To achieve circularity there is the need to add more requirements to the product design that are coming from the concept of circular economy. Therefore, in the current paper we have defined additional design steps that are adding more requirement. Those steps include the incorporation of the product re-use, repurpose, re-manufacture and recycling. We provide a structural approach to quantifying circularity in design in order to close the gap between conventional design methods and sustainability. The presented work was partially supported by the projects CIRCULess and PLOOTO, EU H2020 projects under grant agreements No 101138330 and 101092008.</p
Finalisation of the European approach to assess the fire performance of façades
No full textThis final report summarises the work carried out during the project SI2.825082 financed by the European Commission – DG GROW. Within this project a theoretical Round Robin with the aim to analyse how the initial assessment method is interpreted by different laboratories, and the first and second phase of the initial testing activities to investigate the fire source, the design of the combustion chamber and secondary opening have been carried out. The final step in the project was an experimental Round Robin where four façade systems were tested at three different laboratories using the assessment method document, resulting in 24 tests. Additional tests were added to the project with funding from industrial partners. The tests were used to determine a calibration scheme and suitable performance criteria for classification. Furthermore, a substantial work has been done to ensure that the project is communicated in a good way to all stakeholders and Member States representatives.The theoretical Round Robin was performed with 29 laboratories, all members of European Group of Organisations for Fire Testing, Inspection and Certification (EGOLF). Over 200 questions covering the whole assessment method were asked, and thereafter analysed. The results show clearly which parts of the assessment method needs to be improved and clarified, as well as some practical details regarding the test method that had to be addressed.The first phase of the initial testing program defined the requirements of the fuel source and the combustion chamber. A large quantity of wood, of two different wood species (spruce and pine), had been acquired and thereafter characterised by measurement of dimensions, weight and moisture content. Over 4000 sticks have thus been density graded. After the selection of sticks to the different wood cribs a series of tests have been performed, mainly in accordance with the original test plan. Some modifications to the test plan were made during the course of the experimental study e.g., tests with a crib platform with either a grated or a solid floor. Also, a theoretical study through numerical modelling has been made to study the impact of changes of the combustion chamber geometry on the heat exposure to the test specimen. The simulations showed only small deviations between the regular and the enlarged combustion chamber. The changes of the geometry of the combustion chamber for the large exposure test can be done according to the results from the experimental program, it is beneficial for two reasons: it would make the preparatory work when mounting the test specimen simpler and it would ensure that falling parts will not damage the wood crib during a test.Based on the results a proposal has been made on the characteristics of the fuel source and the geometry and design of the combustion chamber, to be used in the second phase.During the second phase of the initial testing activities large and medium-scale exposure testing was performed on full façade geometries. The testing program including three repeatability tests in addition to gather information on variation in volume flow of the fan in medium-scale exposure as well as effects of the modified combustion chamber and wind in large-scale. From the repeatability tests it was decided to keep a constant height of the wood crib in large-scale due to otherwise large variations in exposure to the façade. Furthermore, the wind effects on the façade temperatures were significant even with a moderate wind of 1-2 m/s. At the end of the second phase three tests in medium and three tests in large-scale were done to investigate the effect of a secondary opening. It was indicated that asymmetrically placed opening would be the most appropriate placement.A short test series on alternative fuel source for the large exposure test was also performed where a propane diffusion burner was used instead of wood cribs. It was shown that if the combustion chamber would be reduced in height similar exposure to the façade could be achieved using the propane burner. There are several benefits with this alternative fuel source such as decreased height, less cleaning, higher safety and therefore less costs associated to10testing. For the medium exposure test the alternative gas burner described in DIN 4102-20 might be an appropriate alternative fuel source for the wood crib. However, no further investigations were made in this project in this regard.An update of the assessment method was made to take into account the latest information such as the repeatability tests and the second phase of the testing program. These changes such as the placement of the wood crib and the secondary opening was used in the experimental Round Robin.In tandem to this work, two surveys on falling parts were performed to find out the needs of Member States (MS) and setting criteria to be used during the Round Robin. Furthermore, an inquiry on the capacities for indoor and outdoor testing of different testing laboratories connected with EGOLF was made and is reported here.The work on the experimental Round Robin was completed in March 2024 and presentations of the tests and specimens are discussed in this report, more detailed information is available in the comparative documents. These include comparisons between tests on the same type of façade system at the different laboratories. This enables inter-laboratory comparisons for each monitored quantity and position. The inert tests are used to determine suitable calibration schemes for the medium and the large-scale exposure method, whereas the remaining tests are used to determine the performance criteria. Here it should be noted that average temperature is a more stable assessment criterion than a peak temperature or above a certain temperature during a certain time interval. The consortium would like to stress that arranging this type of Round Robin exercise is a severe logistic challenge which requires extensive planning.The project has been communicated through different channels. The project web page is the main communication channel where all reports and other documentation is published (https://www.ri.se/en/what-we-do/projects/european-approach-to-assess-the-fire-performance-of-façades). In addition to the webpage a YouTube channel is available showing a few of the tests and recent seminars, see webpage for a link.A Comments Handling Document has been kept and it includes almost 1000 comments that have been received during the project. These comments were handled continuously and communicated through the above-mentioned web page
Predicting maintenance lithium response for bipolar disorder from electronic health records - a retrospective study
No full textBackground: Optimising maintenance drug treatment selection for people with bipolar disorder is challenging. There is some evidence that clinical and demographic features may predict response to lithium. However, attempts to personalise treatment choice have been limited. Method: We aimed to determine if machine learning methods applied to electronic health records could predict differential response to lithium or olanzapine. From electronic United Kingdom primary care records, we extracted a cohort of individuals prescribed either lithium (19,106 individuals) or olanzapine (12,412) monotherapy. Machine learning models were used to predict successful monotherapy maintenance treatment, using 113 clinical and demographic variables, 8,017 (41.96%) lithium responders and 3,831 (30.87%) olanzapine responders. Results: We found a quantitative structural difference in that lithium maintenance responders were weakly predictable in our holdout sample, consisting of the 5% of patients with the most recent exposure. Age at first diagnosis, age at first treatment and the time between these were the most important variables in all models. Discussion: Even if we failed to predict successful monotherapy olanzapine treatment, and so to definitively separate lithium vs. olanzapine responders, the characterization of the two groups may be used for classification by proxy. This can, in turn, be useful for establishing maintenance therapy. The further exploration of machine learning methods on EHR data for drug treatment selection could in the future play a role for clinical decision support. Signals in the data encourage further experiments with larger datasets to definitively separate lithium vs. olanzapine responders. The following grant information was disclosed by the authors: Wellcome Trust: 211085/Z/18/Z. UK Research and Innovation: MR/V023373/1. University College London Hospitals NIHR Biomedical Research Centre. NIHR North Thames Applied Research Collaboration. UK Research and Innovation Medical Research Council: MR/W014386/1.</p
Exploring vacuum foam drying as an alternative to freeze-drying and spray drying for a human lipase
No full textThis article compares and explores vacuum foam-drying as an alternative drying technology to freeze-drying and spray drying for a recombinant human lipase as the model protein. Materials characteristics such as structure, surface composition and the solid-state properties of the dry materials were compared and investigated. Moreover, the technical functionality in terms of reconstitution characteristics and the lipase stability were also investigated. The stability of the lipase was evaluated through activity measurements. Sucrose and dextran D40 (40 kDa) were used as matrix former and the surfactant α-dodecyl maltoside was used as surface active additive. The study demonstrated that the drying technique greatly influenced the material structure and composition which in turn affected the reconstitution characteristics. The lipase was overrepresented at the material surface in declining order spray-dried > vacuum foam-dried > freeze-dried. The lipase activity was retained up to 10 % lipase content in solids, but at 20 % lipase a loss of activity was observed for all drying techniques. Phase separation in the solid material may be an explanation. Vacuum foam-drying shows promise as an alternative drying technique for the lipase, and potentially other proteins. . This research was funded by the Swedish Governmental Agency for Innovation Systems (VINNOVA) and was carried out within the competence centre NextBioForm (grant number 2018-04730).</p
Experimental study of fire propagation on sloped roof with building applied photovoltaics
No full textPhotovoltaic modules have been shown to influence how a fire propagates across a flat roof, but the circumstances for which building attached photovoltaic (BAPV) modules promote fire propagation on a sloped roof is not studied in detail. Therefore, a series of small-medium- and large-scale experiments on a sloped roof with a BROOF(t2)-rated bituminous roof membrane on a wood chipboard substrate has been performed. Steel plates mimicking non-combustible photovoltaic (PV) modules were placed at different distances above the roof. Different sized wood cribs placed in the gap between the roof and the PV module were used as the ignition source. Similarly to findings for flat roofs, the experiments showed that the gap distance and the size of the ignition source are key factors for how far the fire propagates from the starting point. This supports that BAPV installations affect the fire dynamics on roofs. As such, the complete system of roof composition and PV installation needs to be considered as a whole to ensure adequate fire safety levels
Development of large lab-scale fire dynamics experiments relevant for Scandinavian wildfire behaviour
No full textThe Scandinavian countries have in later years seen several severe wildfires and is expected to exhibit more severe fire danger. While direct flame spread has been an important topic in wildfire research, there is a need for development and to ensure that experimental methods are relevant for Scandinavian wildfire characteristics. To ensure relevant lab conditions for fire-resilient material development work, large lab-scale (2×4 meters) experiments were conducted on various fuels. Its fire behaviour (such as rate of spread, fireline intensity and flame length) was compared with ongoing wildfire field studies from ongoing field studies in boreal and hemiboreal Sweden. The lab fire experiments show good potential to mimic relevant natural wildfire conditions in the laboratory once a standard design fire exposure for fire resilient materials is developed
A hybrid workflow connecting a network and an agent-based model for predictive pedestrian movement modelling
No full textPedestrian movement has always been one of the main concerns for urban planning and design, but it has become more important within the sustainable development agenda, as walking is crucial to reducing urban emissions and fostering liveable cities. Therefore, urban planners need to take pedestrian movement into consideration as part of the workflow of planning and designing cities. This study outlines a comprehensive workflow tailored for urban planners. It proposes a hybrid model that integrates an agent-based model, which simulates the micro-scale movement of pedestrians in outdoor urban environments, with a network model, which predicts the aggregated pedestrian flows on a macro-scale. The hybrid model is applied to a pedestrian precinct in the city centre of Gothenburg, Sweden, and is compared to real-world measurements. The reasonable agreement between the simulation results and the real-world data supports the reliability of the proposed workflow, underscoring the model’s ability to statistically predict pedestrian movement on a large scale and individually on a local scale. Furthermore, the model enables the analysis of flow distributions and movement restrictions and facilitates the analysis of different design scenarios and specific pedestrian behaviour. This functionality is valuable for urban design and planning practice, contributing to the optimisation of pedestrian flow dynamics.This work is part of the Digital Twin Cities Centre supported by Sweden’s Innovation Agency Vinnova under Grant No. 2019-00041.</p
Säker Vätgasbunkring
No full text Safe Hydrogen Bunkering Compressed gaseous hydrogen (CGH2) storage and bunkering represent a viable alternative marine fuel with the potential to be entirely fossil-free. However, the adoption of CGH2 introduces unique challenges and risks that require rigorous assessment to ensure its safe and efficient use. CGH2 is favored for its sustainability potential and comparatively lower economic demands relative to liquid hydrogen. Nevertheless, its physical and chemical properties necessitate enhanced safety measures. CGH2 exhibits a broader flammability range, lower minimum ignition energy, and faster combustion rates compared to conventional fuels such as methane. Additionally, its storage under high pressures exceeding 250 bar implies that leaks may lead to hazardous phenomena, including jet flames or deflagrations (explosions). This report emphasizes the safety of personnel, including crew members, terminal workers, and passengers, while investigating the hazards associated with CGH2 bunkering. To this end, existing literature and regulations pertaining to LNG and hydrogen have been reviewed, stakeholder interviews have been conducted for a Visby case study, and a Hazard Identification (HAZID) analysis has been performed. Key hazards identified include loss of containment due to leaks, pipe, or tank ruptures. To effectively manage the risks of CGH2 bunkering, preventive and mitigative strategies must address multiple dimensions. These include operational limits, technical and physical measures, placement and design considerations, hazardous zones, safety distances, and maintenance protocols. Equally important are human factors such as access control, the establishment of clear safety protocols, well-defined roles and responsibilities, and procedural routines. The individual risk measure is used to ensure that no crew, terminal worker, or passenger is exposed to unacceptable risks. Input values for the individual risk calculation, such as limit values, failure frequencies, and consequences have been reviewed. For calculating the individual risk, uncertainty regarding modelling, input parameters and operational practices needs to be carefully managed. The high frequency of CGH2-bunkering drives the risk due to an increase in the number of transfer operations and the time for the system in operation.Denna rapport är ett resultat från ett forskningsprojekt (Säker Vätgasbunkring) finansierat av Stiftelsen Sveriges Sjömanshus. Projektet har genomförts av RISE Research Institutes of Sweden (RISE) och Uppsala universitet (UU). Gotland Tech Development AB har medfinansierat studien och bidragit med viktig kunskap för genomförd fallstudie. Åsikter som presenteras i denna rapport är författarnas och inte finansiärens.</p