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Failure Transparency in Stateful Dataflow Systems
No full textFailure transparency enables users to reason about distributed systems at a higher level of abstraction, where complex failure-handling logic is hidden. This is especially true for stateful dataflow systems, which are the backbone of many cloud applications. In particular, this paper focuses on proving failure transparency in Apache Flink, a popular stateful dataflow system. Even though failure transparency is a critical aspect of Apache Flink, to date it has not been formally proven. Showing that the failure transparency mechanism is correct, however, is challenging due to the complexity of the mechanism itself. Nevertheless, this complexity can be effectively hidden behind a failure transparent programming interface. To show that Apache Flink is failure transparent, we model it in small-step operational semantics. Next, we provide a novel definition of failure transparency based on observational explainability, a concept which relates executions according to their observations. Finally, we provide a formal proof of failure transparency for the implementation model; i.e., we prove that the failure-free model correctly abstracts from the failure-related details of the implementation model. We also show liveness of the implementation model under a fair execution assumption. These results are a first step towards a verified stack for stateful dataflow systems.This work was partially funded by Digital Futures under a Research Pairs Consolidator grant (PORTALS).</p
Sorbic acid is an efficient preservative in pea-based meat analogues
No full textThe popularity of plant-based alternatives to meat has increased due to advancements in important attributes such as taste. Using adequate processing at elevated temperatures combined with aseptic packaging, especially in combination with storage below the freezing point, microbial hazards in these products are negligible. However, for plant-based alternatives to ham, sausages, spreads, or cheese, for example, on sandwiches, the product must withstand microbial growth in the fridge after breaking the seal of the food packaging, as everything is not typically consumed directly. Currently, there are few preservations methods, but one solution is adding weak acid preservatives, with less inherent health concerns compared to sulfites and nitrite, e.g. carcinogenicity and hypersensitivity. To be fully effective an acidic pH is required. In this study, an approach where sausage-resembling meat analogues with different pHs (4.14–5.56) were prepared without preservatives, with potassium sorbate (2000 mg/kg), or sodium disulfite (200 mg/kg), and thereafter subjected to standardised challenge tests to elucidate the efficacy. Sorbate was the only preservative effective to prevent growth of all tested organisms, Penicillium roqueforti, Pichia fermentans and Listeria monocytogenes. The identified superiority of sorbate compared to other tested preservatives is relevant knowledge when developing preservation strategies for other types of meat analogues. This study was performed within FINEST, a research centre financed by the Swedish research council FORMAS (2020–02839).</p
Cellulose foams: Sustainable solutions to replace fossil-based plastic foams
No full textApple and RISE Research Institutes of Sweden are committed to contribute to solving the ongoing plastic pollution crisis. In a joint undertaking, we have created an innovative, low-density, resilient, cellulose foam, based on responsibly sourced wood pulp that can be sustainably produced and recycled in the paper packaging recycling stream. Its structure and mechanical properties suggest it could replace fossil-based materials, such as polymeric foams, commonly used in packaging, insulation, and light weight composites. To accelerate progress, and shorten time to market, we are now inviting partners to build on the work we have done and develop the material toward different applications
Assessing the Impact of Bjørnis the Fire Bear: A Study on Fire Safety in Norwegian Households
No full textThe present research explores the influence of Bjørnis the Fire Bear on residential fire safety in Norway. Our survey, comprising 1275 participants, reveals that Bjørnis spurred the adoption of 5181 fire safety measures among the respondents, averaging 4.1 measures per household. The data suggests a positive association between exposure to Bjørnis and an increased number of safety measures implemented. These results highlight Bjørnis' efficiency in fostering awareness about fire safety, potentially serving as a model for introducing or sustaining similar mascots and initiatives on a global scal
Energibesparingspotential i medeltida kyrkor : En förstudie med dynamisk energiberäkning för ett fiktivt objekt
No full textEnergy saving potential in medieval churches: A preliminary study with dynamic energy calculation for a fictitious object In the project, Energy efficiency and climate change measures with preserved cultural-historical values for wooden roof structures in medieval churches, the following question has been raised: How much is saved by insulating the attic of a medieval church, in relation to other measures such as lowering the indoor temperature? As a first step in answering the question, a preliminary study has been carried out. A dynamic energy calculation has been made for a fictitious church. The effect of insulating was compared to the effect of lowering the temperature. The result shows that the most effective measure of those investigated is to reduce the indoor temperature. To get a clearer picture of which measures are effective for different geometric and geographical conditions, it is recommended that case studies be carried out.Den här rapporten redovisar en förstudie genomförd inom ramen för projektet Energieffektiviserings- och klimatomställningsåtgärder med bevarade kulturvärden för medeltida kyrkors takkonstruktioner av trä. Projektet är finansierat av Energimyndigheten, leds av RISE och genomförs tillsammans med NIKU (Norsk Institutt for Kulturminneforskning).</p
Bevarandet av medeltida kyrktak : bakgrundsdata från kyrkoförvaltare, hantverkare, konsulter och myndighetspersoner
No full textRapporten redovisar data från projektet Energieffektiviserings- och klimatomställningsåtgärder med bevarade kulturvärden för medeltida kyrkors takkonstruktioner av trä. Projektet är finansierat av Energimyndigheten och leds av RISE, med Norsk institutt for Kulturminneforskning (NIKU) som partner. Projektets syfte är att stödja en förvaltning av delar av vårt äldsta bevarade träbyggande där energibesparingsåtgärder, energiomställningsåtgärder och klimatanpassningsåtgärder balanseras mot kulturvärden på ett sådant sätt att ett antal identifierade potentiella hot mot kulturvärdenas bevarande kan undvikas. Data som publiceras här ska kompletteras, bearbetas vidare och spridas på former som passar målgruppen - yrkesverksamma som på olika sätt kommer i kontakt med takkonstruktionerna och deras bevarande.Funding: Energimyndigheten</p
Experimental investigation of dust explosions with a focus on black mass in battery recycling
No full textThe number of batteries in various applications at end-of-life and production waste from battery gigafactories increase significantly. At the same time, new EU regulations are introduced to promote battery recycling, which is a new and rapidly growing business. Large amounts of combustible dust are generated in battery recycling. Managing combustible dust hazards at the battery recycling plants is one of the key factors to minimize the incidents and down time and, therefore, to improve the work environment, and to increase the profitability of the business. Accordingly, the present work aims at exploring the risk of explosion of black mass dusts associated with battery recycling. Specifically, four black mass samples from different battery recycling plants are experimentally investigated. Microscope images, particle size distribution, water content and organic carbonates are analyzed. Dust explosion experiments are performed in a 20-L vessel. Parameters including dust concentration, ignition energy, ignition delay, dust injection pressure are varied. Results show that a 10 kJ ignition energy cannot generate high explosion overpressure, whereas an ignition energy of 20 kJ yields an explosion overpressure above 6 bar for black mass sample C at a concentration of 300 g/m3. The obtained experimental results are compared with published data on various explosion-related characteristics of other dusts relevant to battery recycling, in particular, aluminum and graphite dusts.The Swedish Energy Agency is greatly acknowledged through SafeDust ReLIB project (number P2023-00060), a pre-study on dust explosion risks for Lithium-Ion Battery Recycling.</p
On the nature of the selectivity of oxygen delignification
No full textThis work has focused on oxygen’s role in the delignification process within the context of pulp production. We have investigated the role of oxygen in a complex set of chemical reactions taking place during this process, including both oxidative and non-oxidative reactions. This study explores the impact of pH changes during the oxygen delignification process and the characteristics of the resulting pulps. Additionally, this research examines the effect of oxygen, by comparing conventional oxygen delignification with trials using air and nitrogen. Industrial softwood kraft pulps with a kappa number of 35 were subjected to delignification for 20-120 min under alkaline conditions. The resulting pulps were assessed for kappa number, intrinsic viscosity, fiber charge, and ISO brightness. An important observation from this research is the reduction in lignin molecular weight upon exposure to oxygen and air, suggesting depolymerization reactions facilitated by oxygen species, whereas nitrogen exposure results in less pronounced changes. This finding underscores the impact of oxygen in altering lignin structure, thus informing the selectivity and effectiveness of the delignification process. The work was performed within thestrategical innovation program BioInnovation – a jointinitiative by Vinnova (Sweden’s innovation agency), Formas(Swedish governmental research council for sustainabledevelopment), and the Swedish Energy Agency.</p
Food Loss and Waste : Quantification, Impacts and Potential for Sustainable Managemen
No full textAccording to the UN Environment Program, approximately 1.052 billion tonnes of food are wasted annually, equivalent to about one third of all food produced for consumption (1). Food waste is an issue that poses societal, economic, and environmental impacts. Worldwide, efforts and initiatives are being developed and implemented to reduce food waste. There is a specific Sustainable Development Goal relating to food waste, UN SDG 12.3; “By 2030, halve per capita global food waste at the retail and consumer levels and reduce food losses along production and supply chains, including post-harvest losses” (2).Food Loss and Waste (FLW) occurs at each stage of the supply chain, including primary production, processing, at retailers, within the food service industry, and in households. Food loss refers to a decrease in the mass or quality of food before it reaches the consumer. Food waste typically refers to food that humans did not ultimately consume and that is discarded.It is crucial to understand where food is wasted and how much is wasted along the supply chain to devise interventions to reduce wastage and quantify baselines and progress towards SDG 12.3. Major sources of food loss in the supply chain include; harvest losses, storage losses, processing losses and distribution losses. Further, the generation of food waste is closely tied to the efficiency of the supply chain. Waste occurs for several reasons, including; procurement issues, limited market access for small farmers, quality standards and penalties and market system changes. The food system is a major contributor to environmental impacts, including producing significant greenhouse gas (GHG) emissions. Food production requires extensive resources such as land, fertiliser, water etc. As food is wasted along the supply chain, it results in environmental impacts as all upstream activities and resources used in production are wasted. Furthermore, FLW causes water pollution and nitrogen loss. The environmental impacts of different waste management options for municipal food waste, includingavoidance, composting, anaerobic digestion (AD) and incineration have been considered using Life cycle assessment (LCA). An avoidance strategy for wasted food showed the best environmental performance, while AD resulted in the lowest environmental impact for unavoidable food residues and minimal food waste. Current treatment methods are suboptimal, including landfilling, incineration, composting and anaerobic digestion, each of which has environmental impacts. Food waste contains valuable materials, such ascarbohydrates, lipids and amino acids, and it is a promising feedstock for producing valueadded chemicals and fuels. It is important to characterise food waste to identify optimal valorisation routes, extracting higher value from food waste while reducing impacts.The consumption stage is the final stage in the food supply chain where individuals or households purchase, prepare, and consume the food products. In 2019, 17% of the total food available to consumers was wasted. The dynamics impacting consumer attitudes and behaviours regarding food waste are a complex mix of socio-economic, social, psychological, situational and demographic factors. Campaigns which focus on social norms and behaviours of others and educational campaigns aimed at improving consumers’ knowledge and skills in cooking and food storage have been recommended to tackle food waste. In addition to food waste generated from food which ends up in a bin, waste from food packaging and water scarcity also amplify the overall environmental, social and economic impacts of food waste
Vulnerability analysis method for manufacturing Case study of emergency production of mask
No full textPurpose To support the vision of Industry 5.0 manufacturing companies must ensure human centricity, sustainability and resilience. In this article human-centricity, sustainability and resilience is supported through a vulnerability analysis performed on the emergency production of face masks. The aim was to analyse vulnerabilities/risks and find an approach applicable for critical and emergency production in the case of face mask production. Design/methodology/approach The production process, not in continuous use, was observed and analysed by operation personnel and assessment experts covering different aspects. In the vulnerability analysis energy, material, personnel, and maintenance supply of a production process for face masks was analysed. Findings Findings show that instructions and manuals as well as procedures for how to employ and train personnel need to be part of the emergency/contingency planning, it is not enough to store the equipment. New opportunities using digital and visual technologies can be utilised. Research limitations/implications The emergency production of face masks is an example of moving from Manufacturing readiness level (MRL) 6 to 10, which includes supporting the human need for instructions, looking at waste and material production as well as handling resilience through emergency preparedness Practical and Social implications This research is crucial for society since during Covid, Swedish healthcare needed temporary domestic production of personnel protective equipment. The analysis can be supplemented with social and environmental sustainability assessment. Original/value This paper contributes with enhanced practical and academic understanding of human factor importance in emergency production