RISE – Research Institutes of Sweden
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Radiated Electromagnetic Emission from Photovoltaic Systems—Measurement Results : Inverters and Modules
No full textRadiated electromagnetic emission of photovoltaic systems, for example, adversely impacting radiocommunication, can pose a major barrier against further increase in photovoltaic penetration. This is particularly the case near sensitive infrastructure and activities such as hospitals, airports, search and rescue, and military. To understand the impact of each component and installation detail, we performed systematic radiated electromagnetic emission measurements on comparable commercial photovoltaic systems in the frequency range 150 kHz to 30 MHz. Our measurements indicate that string inverters are unlikely to interfere with radiocommunication when installed according to recommended standards, rules, guidelines, and regulations. It was shown that module-level power optimizers are the main cause of high levels of radiated emissions. The frameless bifacial module showed higher levels of radiated emissions than the monofacial module with frame. Changes in cable management and earthing have less impact on radiated emissions than the choice of solar inverter concept and module type. This research was funded by the Swedish Energy Agency, grant numbers P2020-90239 and 50982-1 and grant numbers P2021-90275 and 52693-1</p
How are we handling protein drugs in hospitals? : A human factors and systems engineering approach to compare two hospitals and suggest a best practice
No full textBiopharmaceuticals are complex biological molecules that require careful storage and handling to ensure medication integrity. In this study, a work system analysis of real-world protein drug (PD) handling was performed with the following goals: identify main barriers and facilitators for successful adherence to accepted recommendations in PD handling, analyse differences in two organizations, and define a Best Current Practice in the real-life handling of PDs based on the results of the work system analysis. Observational study was held in two university hospitals in Spain and Sweden. Based on the Systems Engineering Initiative for Patient Safety (SEIPS) model, the tools chosen were: the PETT scan, in order to indicate the presence of barriers or facilitators for the PETT components (People, Environment, Tools, Tasks); the Tasks and tools matrices to construct a checklist to record direct observations during the real-life handling of biopharmaceuticals, and the Journey map to depict the work process. Observations were performed between March and November 2022. Each episode of direct observation included a single protein drug in some point of the supply chain and considered all the elements in the work system. Based on the results of the work system analysis and the literature review, the authors propose a list of items which could be assumed as Best Current Practice for PDs handling in hospitals. There were a total of 34 observations involving 19 PDs. Regarding People involved in the work process, there was a diversity of professionals with different previous training and knowledge, leading to an information gap. With respect to Environment, some structural and organizational differences between hospitals lead to risks related to the time exposure of PDs to room temperature and mechanical stress. Some differences also existed in the Tools and Tasks involved in the process, being especially relevant to the lack of compatibility information of PDs with new technologies, such as pneumatic tube system, robotic reconstitution, or closed-system transfer devices. Finally, 15 suggestions for best current practice are proposed. Main barriers found for compliance with accepted recommendations were related to the information gap detected in professionals involved in the handling of protein drugs, unmonitored temperature, and the lack of compatibility information of protein drugs with some new technologies. By applying a Human Factors and Systems Engineering Approach, the comparison of two European hospitals has led to a suggested list of Best Current Practices in the handling of protein drugs in a hospital. This project has received funding from the Innovative Medicines Initiative 2 Joint Undertaking (JU) under grant agreement No 101007939. The JU receives support from the European Union\u2019s Horizon 2020 research and innovation programme and EFPIA</p
Performance analysis and production of aromatics for ex situ catalytic pyrolysis of engineered WEEE
No full textEx situ catalytic pyrolysis of engineered waste electrical and electronic equipment (WEEE) was conducted in a two-stage reactor using HZSM-5 catalyst. The effect of the catalysis temperature and the catalyst-to-feedstock (C/F) ratio on products yield, gas and oil composition, and products characterization were investigated in this study. Results indicated that lower reforming temperature and C/F ratio favored organic fractions production. The highest yield of organic fraction was obtained at a catalysis temperature of 450 °C and at a C/F ratio of 0.15, corresponding to 28.5 and 27.4 wt %, respectively. The highest selectivity toward aromatic hydrocarbons and the lowest TAN value of the organic fraction were obtained at a catalysis temperature of 450 °C and a C/F ratio of 0.2, respectively. Most of the alkali and transition metals and 23 % of Br remained in the solid residue after the catalytic pyrolysis of low-grade electronic waste (LGEW). The authors would like to acknowledge the Swedish Energy Agency(Energimyndigheten) (project number 51219–1) for the financial support. Furthermore, the authors acknowledge the Research Institute of Sweden (RISE) for the help and technical support as well as Boliden Rönnskär for providing the WEEE material.</p
Re-configuring practices in times of energy crisis – A case study of Swedish households
No full textDuring the autumn, winter and early spring of 2022/2023, Europe faced rapidly increasing energy prices and threats of power cuts. The situation was consequently labelled an “energy crisis”, and one sector that was severely affected was households. In response to the situation, European households made efforts to reduce and time-shift their energy use to mitigate the effects of the crisis. Considering that domestic energy practices are often difficult to change, particularly in the long term, we find this effect of the energy crisis on households important to understand more deeply. In this paper, we use social practice theory to investigate how Swedish households responded to the crisis and what changes they made in terms of re-configurations of their practices. The aim was to contribute knowledge on how households adapt to a changing energy system with volatile prices, limitations in electric power, and threats of energy crisis. We conducted two rounds of semi-structured interviews with 9 households in single-family houses in the middle and south of Sweden during and after the crisis, in total 18 interviews, to examine what re-configurations of practices emerged and which persisted over time. The results show that significant changes were apparent in primarily the practice domains of heating and hygiene. While some of these changes were temporary, other re-configurations of energy practices persisted beyond the months of crisis and high prices, indicating that meanings of frugality and sufficiency were strengthened. Our results demonstrate that households were reminded of certain electricity use that is otherwise typically backgrounded in homes and that the energy crisis stimulated re-configuration and re-examination of norms as well as reflection on electricity use in general. Finally, we discuss the effects of the energy crisis on household practices in comparison with other crises and disruptions, and point to the importance of communicating clearly with households about the societal effects of their efforts, in order to manage the legacy of this crisis for similar future crisis situations. This research was funded by the Swedish Energy Agency, grant No. P50343-1. </p
Knowledge translation gaps that need to be bridged to enhance life for people with spinal cord injury
No full textThere is a ‘need to know’ for people who have acquired a spinal cord injury (SCI) and a ‘lack of knowledge’ is considered to be a barrier to coping with SCI. In-patient SCI care and rehabilitation have emphasized that information should be provided in the right amounts, at the right place and at the right time. Such needs and timing probably go beyond initial care and rehabilitation. Likewise, there is also, reasonably a need for knowledge for other groups of people meeting people with SCI, such as relatives, health professionals and personal care assistants1 as well as authorities, decision-makers, employers, architects and city planners etc. Our recent work, shows that more evidence is needed regarding the provision of specialist expertise in SCI by care services and to what extent they are therefore able to respond to the needs of people living with SCI. A Swedish need assessment project, including a priority setting partnership (PSP2 ) according to James Lind Alliance, has been implemented nationwide 2021–22 to address the needs which are most important for people with SCI to enhance their lives. The Swedish need assessment project comprises three parts: (a) needs to be met; (b) questions to be answered; (c) knowledge required. In part (b), which is the PSP we have identified research priorities (e.g. knowledge gaps); while in part (c), presented here, we report results from an online survey addressing knowledge translation gaps in order to shed light on the knowledge that is available yet which does not reach out. An online survey was released in November–December 2021 with people with SCI, relatives of people with SCI and health professionals and care assistants working with people with SCI. This survey included an open-ended question concerning knowledge translation gaps – what kind of knowledge is lacking and who needs the knowledge. In total, 242 persons responded the survey. Table 1 provides personal characteristics. Each respondent could state one to five knowledge needs, resulting in 480 inputs (statements with more than one need were treated separately in the total number of inputs). However, 84 statements were removed due to beyond the scope of the study (e.g., addressing general needs not related to needs for knowledge). The statements where further complemented with 64 statements from the PSP question (where these were asked for issues which were difficult to find answers to). Thus, this report is based on a total of 459 statements included in this study.The project was funded by the Gothenburg Competence Center for Spinal Cord Injury and the Swedish Association for Survivors of Accident and Injury (RTP).</p
Purification of soda lignin
No full textPurity of technical lignin is one of the main obstacles in the utilization of lignin to value-added chemicals, products, and materials. The objective of this study was to investigate and compare single and two stage purification methods for obtaining soda lignin with high purity. Extensive washing and extraction with water was found effective, increasing the abundance of acid insoluble lignin while reducing its ash content. Extraction with organic solvents was conducted with 2-propanol or blends of n-heptane/1-butanol or cyclohexane/acetone. These solvents were shown to have little effect on the total lignin content, as determined by wet-chemical methods. Two-stage treatments (washing with water followed by solvent extraction) were hence not better than single stage water extraction in terms of the lignin purity. Still, selective removal of low molecular weight components after solvent extraction was noted, reducing the overall polydispersity of the lignin. Evaporation at 40 °C also showed little effect, whereas calcination at 150 °C significantly increased the molecular weight of the soda lignin. The latter effect was explained by thermally induced cross-linking. In addition, the UV absorbance of the calcinated lignin increased, which is likely related to changes in the aromatic structure. Such effect also entailed that UV/vis spectrophotometry was found less reliable in determining the total lignin content. At last, a mathematical model was adapted to predict the total lignin content from FTIR spectrometry. In conclusion, the tested procedures can be used to purify soda lignin and adjust its molecular weight.This work was carried out as a part of project “LignoWax – Green Wax Inhibitors and Production Chemicals based on Lignin”, Grant no. 326876. The authors gratefully acknowledge the financial support from the Norwegian Research Council, Equinor ASA, and ChampionX Norge AS. </p
Chemical compatibility between poly(ethylene) and cellulose nanofibers from kraft pulps containing varying amounts of lignin : An aqueous acetylation strategy and its effect on biocomposite properties
No full textPrevious efforts to acetylate fibers and cellulose nanofibers (CNFs) are methodologically demanding and usually based on organic solvents catalyzed by acids. Hence, the purpose of this study was to introduce an improved method to acetylate unbleached (2 % and 5 % lignin) and bleached fibers (<1% lignin), and the corresponding CNFs, using a one-pot strategy in an aqueous alkaline medium. The lignin content in the pulp fibers (5 %) influenced the morphology of the corresponding fibrillated materials, i.e., increased secondary fines (92 %) and mean fibril area (36 %). Additionally, the pulps and CNFs (0 % and 5 % lignin content) were acetylated and compounded with high-density poly(ethylene) (HDPE). Acetylation improved the mechanical strength from 19 MPa (HDPE) to 30–40 MPa (when including acetylated fibers or CNFs). Finally, acetylation revealed a positive effect on melt-flow-index and elongation at break, and the water absorption of injection molded specimens was reduced to roughly 0.6 % after 10 days of testing. The Research Council of Norway and the companies supporting the WoBiCo project “From wood to sustainable biocomposites” (Grant no. 328773) are thanked for funding. The Research Council of Norway is also acknowledged for the support to the Norwegian Micro- and Nano-Fabrication Facility, NorFab, project number 295864.</p
A survey on the evolution of stream processing systems
No full textStream processing has been an active research field for more than 20 years, but it is now witnessing its prime time due to recent successful efforts by the research community and numerous worldwide open-source communities. This survey provides a comprehensive overview of fundamental aspects of stream processing systems and their evolution in the functional areas of out-of-order data management, state management, fault tolerance, high availability, load management, elasticity, and reconfiguration. We review noteworthy past research findings, outline the similarities and differences between the first (’00–’10) and second (’11–’23) generation of stream processing systems, and discuss future trends and open problems. We thank the anonymous VLDBJ reviewers for their detailed and valuable feedback on prior drafts of this paper. This work was partially supported by a Google DAPA award, WASP NESTS (Data-Bound Computing), and the Dutch Research Council (NWO) Vidi project No. 19708.</p
SALIENCE4CAV Public Report : Safety Lifecycle Enabling Continuous Deployment for Connected Automated Vehicles
No full textConnected automated vehicles (CAVs) are—compared conventional vehicles—expected to provide more efficient, accessible, and safer transport solutions in on-road use cases as well as confined areas such as mines, construction sites or harbours. As development of such vehicles has proved more difficult than anticipated, especially when it comes to ensuring safety, more cautious strategies for introduction are now being pursued. An approach where new automated features are initially released with more basic performance to enable successful safety assurance, followed by gradual expansion of performance and number of use-cases using an iterative development process as the confidence in the solution increases, e.g., due to more available field data, improved machine learning algorithms, or improved verification, is highly interesting. Hence a key research question targeted by the SALIENCE4CAV project was: How to ensure the safety of CAVs while enabling frequent updates for automated driving systems with their comprising elements? Today, many of the used methods and practices for safety analysis and safety assurance are not adequate for continuous deployment. In addition, the project has investigated several open questions raised by the predecessor project ESPLANADE and from needs identified by the industry partners; this includes how to handle safety assurance for machine learning components, use of quantitative risk acceptance criteria as a key part of the safety argument, safety for collaborative CAVs including use in mixed traffic environments, the role of minimal risk manoeuvres, and interaction with human operators. Some key results are: investigation of safety assurance methods and gaps with regards to frequent updates and other challenges for CAV safety assurance; use of safety contracts as an enabler for continuous integration, continuous deployment and DevOps; a method for human interaction safety analysis; application of the principle of precautionary safety for meeting a quantitative risk norm and using field data for continuous improvements; definition of classes of cooperative and collaborative vehicles and their respective characteristics and definition of minimal risk manoeuvre and minimal risk condition strategies for individual, cooperative and collaborative vehicles; use of out-of-distribution detection for safety of machine learning; a simulation-aided approach for evaluating machine learning components; and methods for variational safety using high-dimensional safety contracts. The SALIENCE4CAV project ran from January 2021 to December 2023 with the partners Agreat, Comentor, Epiroc Rock Drills, KTH Royal Institute of Technology, Qamcom Research and Technology, RISE Research Institutes of Sweden, Semcon Sweden, Veoneer (during the project acquired by Magna) and Zenseact. Coordination was done by RISE. This final report is a summary of the project results and contains summaries of content from the project deliverables and publications
Initial evaluation of measurement properties of the Work Environment Impact Questionnaire (WEIQ) - using Rasch analysis
No full textBackground: To provide both preventive and rehabilitative conditions in a workplace, one must understand how employees experience work demands. Such an understanding can be obtained from each individual with valid and quality-assured questionnaires. The Work Environment Impact Questionnaire (WEIQ) is a new questionnaire for measuring employees’ self-perceived work ability in relation to their specific workplace environment. The purpose of this study was to assess the measurement properties in terms of construct validity of the WEIQ. Methods: A cross-sectional survey study was conducted with 288 respondents from three different workplaces involving assisted living personnel, vocational rehabilitation personnel and personnel at a research institute. The measurement properties of the WEIQ were assessed according to Rasch Measurement Theory (RMT), including assessment of item-to-sample targeting, threshold ordering, item fit statistics, unidimensionality and reliability. Results: Item fit, i.e., fit residuals, item characteristic curves (ICC) and chi square values, were all satisfactory, and no disordered thresholds were present after collapsing the lowest response categories. However, issues with local dependent (LD) item correlations was present in 7.6% cases, four items showed statistically significant differential item functioning (DIF), where 11% of the respondents had person fit residuals outside the recommended range of ± 2.5 and the t-test for unidimensionality did not meet the criterion of 5%. Scale-to-sample targeting and reliability (0.92) were good. LD could be resolved with testlets and at the same time maintaining fit and improving dimensionality, but then the reliability decreased to 0.82. Conclusions: This study provides an initial validation of the WEIQ to be used for assessing employees’ self-perceived work ability. Most measurement properties were acceptable, but further exploration of LD, DIF and unidimensionality in additional work settings and with larger sample sizes is warranted. Trial registration: Not applicable.Part of this work has been funded by the Swedish innovation agency, VINNOVA Dnr 2018–02512 project RISE Social and Health Impact Centre</p