| 1. |
- Andersson, Petra, et al.
(författare)
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Lion Fire: Extinguishment and mitigation of fires in Li-ion batteries at sea
- 2018
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The shipping industry is facing increasing pressure to cut emissions. Diesel-electric hybrid or fully electrical propulsion systems can offer significant savings in fuel consumption and reduce emissions. However, the use of energy storage battery systems on board vessels is introducing new fire hazards and advice on suitable fire extinguishing systems and agents is desired. In a series of tests, both total compartment application water spray and water mist systems and direct injection (using several different agents) into the module were evaluated in fire tests conducted to compare different fire extinguishing approaches for a fire in a battery cell. A test compartment was constructed to simulate a battery room and a commercially available lithium-ion (Li-ion) battery cell was positioned inside a cubic box that mimicked a battery module. By heating the battery cell, combustible gases were generated, and these gases were ignited by a pilot flame inside the simulated battery module. The tests indicated that fire extinguishment of a battery cell fire inside a battery module is unlikely when using total compartment water spray or water mist fire protection systems. The water droplets are simply not able to penetrate the battery module and reach to the seat of the fire. Direct injection of the fire extinguishing agent inside the battery module is necessary. The tests also showed that agents such as water and low-expansion foam, with a high heat capacity, provide rapid cooling and fire extinguishment. The reduced water surface tension associated with low-expansion foam may improve the possibilities for water penetration whilst agents with a high viscosity may not be able to spread to the seat of the fire. Agents with less heat capacity, such as high-expansion foam and nitrogen gas, provide less cooling but fire extinguishment can still be achieved if designed correctly.
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| 2. |
- Bisschop, Roeland, et al.
(författare)
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Handling Lithium-Ion Batteries in Electric Vehicles: Preventing and Recovering from Hazardous Events
- 2020
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Ingår i: Fire technology. - : Springer. - 0015-2684 .- 1572-8099. ; 56, s. 2671-2694
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Tidskriftsartikel (refereegranskat)abstract
- The demand for lithium-ion battery powered road vehicles continues toincrease around the world. As more of these become operational across the globe,their involvement in traffic accidents and incidents is likely to rise. This can damagethe lithium-ion battery and subsequently pose a threat to occupants and respondersas well as those involved in vehicle recovery and salvage operations. The project thispaper is based on aimed to alleviate such concerns. To provide a basis for fire safetysystems to be applied to damaged EVs, hazards have been identified and means forpreventing and controlling lithium-ion battery fires, including preventive measuresduring workshop and salvage activities were studied. Tests were also performed withfixed fire suppression systems applying suppressant inside traction batteries whichshowed to improve their safety.
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| 3. |
- Bäcklander, Gisela, 1983-
(författare)
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Autonomous, yet Aligned : Challenges of Self-Leadership in Context
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Följande avhandling bidrar till teorier om ledning av kunskapsarbete på mikronivå, genom att undersöka självledarskap i kunskapsarbete och organisatoriska försök att främja det på individ- och teamnivåer. Det empiriska materialet är insamlat i kontexter av innovativ mjukvaruutveckling, konsulter, och aktivitetsbaserat arbetssätt; metoden är företrädesvis djupintervjuer och tematisk analys, och i papper IV enkät och statistisk analys. Den övergripande forskningsfrågan har varit: Hur kan organisationer stödja hållbart och produktivt självledarskap hos sina anställda? I papper I framträder en förmåga att “se” vilket arbete som skulle göras. Det antyder att situationellt omdöme och uppmärksamhet är nyckelingredienser i vad som slutligen ses som framgångsrikt självgående eller självledarskap hos anställda. I papper II indikerar kunskapsarbetare själva att en förväntan att kunna ”utläsa” chefens/omgivningens krav som något som bidrar till ett internaliserande av krav och att man ser sig själv som källan till stress. Konsulterna i studien uttryckte en tro på interna själv-disciplinära strategier av en mer reaktiv natur som det som skulle göra dem mer självledande. I själva verket så visade deras berättelser istället på att det snarare var mer externa och proaktiva strategier (att välja eller ändra arbetsmiljön) som fungerade bäst i praktiken, vilket rimmar väl med den forskning om begränsade resurser för självreglering som publicerats på senare tid. Baserat på papper I & II så undersöker papper IV kvantitativt hypotesen att ha god tillgång till arbetsrelevant information (“information richness”) skulle ha ett starkare samband med lägre kognitiv stress, och bättre prestation, är de interna och självfokuserade strategier som förordas i det etablerade konceptet och måttet self-leadership (självledarskap). I synnerhet i en kontext av aktivitetsbaserat arbete, där medarbetarna själva har stark möjlighet att bestämma hur, var, när, och med vem de utför arbete. Hypoteserna bekräftades i stort, vilket tyder på att när organisatoriska situationer inte kan konfigureras starkt, till exempel eftersom den bästa arbetsprocessen inte är känd, eller för att innovation eller olika samarbeteskonstellationer krävs, så behöver de berikas så att den orientering och om-orientering som anställda behöver göra inte blir för belastande för den enskilda och försämrar kognitiv funktion och prestation. Papper III är en fallstudie av agila coacher (AC) på Spotify och hur de praktiserar ett underlättande ledarskap (”enabling leadership”), en central, balanserade kraft inom complexity leadership theory (Uhl-Bien, Marion, & McKelvey, 2007). Coacher praktiserar underlättande ledarskap genom att öka kontext-känsligheten hos andra, genom stöd till andra ledarroller, genom att etablera och förstärka enkla beslutsprinciper, observera gruppdynamik, synliggöra motsättningar och underlätta och uppmuntra konstruktiv dialog. AC som komplexitetsledare värderar att vara närvarande, observera och reagera i ögonblicket. Fynden antyder att den flexibla struktur som en uppmärksam coach bidrar med kan vara ett fruktsamt sätt att navigera och balansera autonomi och målstyrning, att ha en gemensam riktning.Omformuleringen av konceptet självledarskap i den här avhandlingen pekar på vikten av att, som individ, 1) kunna navigera ”svaga” situationer och att se eller skapa sina egna arbetsuppgifter på ett sådant sätt som gör ett värdefullt bidrag till organisationen, och 2) ha möjligheten att avlasta kognitiva krav på sin miljö i bred mening. Att stödja självledarskap innebär i så fall att stödja dessa två huvudmekanismer. Och med ett resursperspektiv kan vi säga att organisationer kan erbjuda stöd genom att bygga eller erbjuda resurser av olika slag, som i sin tur låter medarbetare ha mer kvar av sina interna, personliga resurser för de tillfällen då de verkligen behövs.
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| 4. |
- Jägerskog, Ann-Sofie, 1977-, et al.
(författare)
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Visualising the complex and the changing : Identifying critical aspects of social science models
- 2022
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Ingår i: Earli SIG9 2022: Phenomenography and variation theory in practice. - Stockholm.
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Konferensbidrag (refereegranskat)abstract
- Extended summaryWe live in a world that is rapidly changing and what we believe to be true today may very well be overturned tomorrow. Many of the issues raised in social studies education are characterized by changeability and complexity, such as conflicts, sustainable development, issues of justice, as well as political, social and economic processes. One common way of helping students to grasp the complex relations and the changeability involved in social studies related issues is to use models. Examples of models often used in social studies teaching are models illustrating sustainable development or political processes, as well as illustrations of the socio-economic cycle and diagrams visualizing relations between different factors in society. However, teacher experience as well as earlier research indicate that students often find it difficult to understand and interpret models (see for instance Roberts & Brugar, 2017; Jägerskog, 2020; Sundler, Dudas & Anderhag, 2017). In addition, there is a risk that these seemingly fixed models do not offer an understanding of the changeability in societal issues. The aim of this presentation is to discuss how phenomenography and variation theory (with a focus on critical aspects) can increase our understanding of how models used in social studies teaching can help students understand the complexity and changeability in societal issues. The aim is also to discuss the possible transferability of critical aspects between different kinds models used in social studies teaching. The presentation is based on a project aiming at identifying students’ understanding of two kinds of models (flowcharts and plot diagrams) often used in social studies teaching, and what students need to discern in order to develop the ability reason in a qualified way about the content illustrated. The material analysed consists of 46 recorded and transcribed small group discussions where students in year 6 and 8 in compulsory school and year 1 in upper secondary school discuss a question that concerns either a flowchart illustrating the democracy system in Sweden, a flowchart of the socio-economic cycle, a plot diagram illustrating the relationship between different countries’ GDP and level of CO2 emissions, or a plot diagram illustrating the relationship between birthrate per woman in different countries and the amount of years girls in these countries attend to school. The transcribed material was analysed using phenomenographic methods and critical aspects were identified for the four different models investigated (Marton, 2015). Results show that the critical aspects identified in part can be understood as model and content specific, but in part as model generic. This means that although two flowcharts (or two plot diagrams) illustrate different content, the aspects identified as necessary for students to discern in order to reason about the content illustrated in a qualified way, are very similar. Although similarities are especially clear between models of the same kind (i.e between two different plot diagrams or two different flowcharts), similarities can also be found between the different kinds of models (i.e between flowcharts and diagrams).This raises questions concerning the transferability of critical aspects between different kinds of models and if aspects that reoccur in relation to different models, such as aspects of changeability and complexity, could be understood as especially characteristic for social studies models. ReferencesJägerskog, A., (2020). Making possible by making visible. Learning through visual representations in social science. (Doktorsavhandling). Stockholms universitet.Marton, F. (2015). Necessary conditions of learning. Routledge.Roberts, K. L., & Brugar, K. A. (2017). The view from here: Emergence of graphical literacy. Reading Psychology, 38(8), 733-777.Sundler, M., Dudas, C. & Anderhag, P. (2017). Från missförstånd till klarhet: hur kan undervisningen organiseras för att stötta elevers förståelse för växthuseffekten? Forskning om undervisning och lärande, 5(2), 6-29.
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| 5. |
- Norrman, Emma, et al.
(författare)
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Cardiovascular disease, obesity, and type 2 diabetes in children born after assisted reproductive technology: A population-based cohort study.
- 2021
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Ingår i: PLoS medicine. - : Public Library of Science (PLoS). - 1549-1676. ; 18:9
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Tidskriftsartikel (refereegranskat)abstract
- Some earlier studies have found indications of significant changes in cardiometabolic risk factors in children born after assisted reproductive technology (ART). Most of these studies are based on small cohorts with high risk of selection bias. In this study, we compared the risk of cardiovascular disease, obesity, and type 2 diabetes between singleton children born after ART and singleton children born after spontaneous conception (SC).This was a large population-based cohort study of individuals born in Norway, Sweden, Finland, and Denmark between 1984 and 2015. Data were obtained from national ART and medical birth registers and cross-linked with data from national patient registers and other population-based registers in the respective countries. In total, 122,429 children born after ART and 7,574,685 children born after SC were included. Mean (SD) maternal age was 33.9 (4.3) years for ART and 29.7 (5.2) for SC, 67.7% versus 41.8% were primiparous, and 45.2% versus 32.1% had more than 12 years of education. Preterm birth (<37 weeks 0 days) occurred in 7.9% of children born after ART and 4.8% in children born after SC, and 5.7% versus 3.3% had a low birth weight (<2,500 g). Mean (SD) follow-up time was 8.6 (6.2) years for children born after ART and 14.0 (8.6) years for children born after SC. In total, 135 (0.11%), 645 (0.65%), and 18 (0.01%) children born after ART were diagnosed with cardiovascular disease (ischemic heart disease, cardiomyopathy, heart failure, or cerebrovascular disease), obesity or type 2 diabetes, respectively. The corresponding values were 10,702 (0.14%), 30,308 (0.74%), and 2,919 (0.04%) for children born after SC. In the unadjusted analysis, children born after ART had a significantly higher risk of any cardiovascular disease (hazard ratio [HR] 1.24; 95% CI 1.04-1.48; p = 0.02), obesity (HR 1.13; 95% CI 1.05-1.23; p = 0.002), and type 2 diabetes (HR 1.71; 95% CI 1.08-2.73; p = 0.02). After adjustment, there was no significant difference between children born after ART and children born after SC for any cardiovascular disease (adjusted HR [aHR]1.02; 95% CI 0.86-1.22; p = 0.80) or type 2 diabetes (aHR 1.31; 95% CI 0.82-2.09; p = 0.25). For any cardiovascular disease, the 95% CI was reasonably narrow, excluding effects of a substantial magnitude, while the 95% CI for type 2 diabetes was wide, not excluding clinically meaningful effects. For obesity, there was a small but significant increased risk among children born after ART (aHR 1.14; 95% CI 1.06-1.23; p = 0.001). Important limitations of the study were the relatively short follow-up time, the limited number of events for some outcomes, and that the outcome obesity is often not considered as a disease and therefore not caught by registers, likely leading to an underestimation of obesity in both children born after ART and children born after SC.In this study, we observed no difference in the risk of cardiovascular disease or type 2 diabetes between children born after ART and children born after SC. For obesity, there was a small but significant increased risk for children born after ART.ISRCTN11780826.
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| 6. |
- Norrman, Emma, et al.
(författare)
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Type 1 diabetes in children born after assisted reproductive technology: a register-based national cohort study
- 2020
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Ingår i: Human Reproduction. - : Oxford University Press (OUP). - 0268-1161 .- 1460-2350. ; 35:1, s. 221-231
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Tidskriftsartikel (refereegranskat)abstract
- References STUDY QUESTION Do children born after assisted reproductive technology (ART) have an increased risk of developing type 1 diabetes? SUMMARY ANSWER Children born after ART were found to have an increased risk of type 1 diabetes in the unadjusted analysis, while after adjustment this association was only significant in children born after frozen embryo transfer. WHAT IS KNOWN ALREADY? Some studies raise concerns as to whether fertility treatments may influence long-term morbidity in children born after ART. Elevated blood pressure and altered glucose metabolism have been found after ART in a few studies. STUDY DESIGN, SIZE, DURATION A register-based national cohort study that included all children born in Sweden between 1985 and 2015-in total, 3138540 children-was carried out. PARTICIPANTS/MATERIAL, SETTING, METHODS The study was population-based and all live-born singleton children born after ART (n=47938) or spontaneous conception (SC) (n=3090602) were included. The ART cohort comprised 36727 children born after fresh embryo transfer and 11211 children born after frozen embryo transfer. Several national registries were used together with data from Statistics Sweden. MAIN RESULTS AND THE ROLE OF CHANCE In total, 202 children born after ART and 17916 children born after SC developed type 1 diabetes, corresponding to 43.4 and 35.5 per 100000 person-years at risk (hazard ratio [HR] 1.23; 95% confidence interval [CI], 1.07 to 1.42). Mean follow-up was 9.7 (SD 6.4) years for ART children and 16.3 (SD 9.2) years for SC children. After adjustment for calendar year of birth, HR for type 1 diabetes was 1.13; 95% CI, 0.98-1.30. After further adjustment for sex, maternal age, country of birth, educational level, smoking and parental diabetes, HR was 1.07; 95% CI, 0.93-1.23. In subgroup analyses, an association was found between frozen embryo transfer and type 1 diabetes (adjusted HR 1.52; 95% CI, 1.08-2.14 and 1.41; 95% CI, 1.05-1.89 for frozen versus fresh and frozen versus SC, respectively). When comparing intracytoplasmic sperm injection to in vitro fertilization, no difference was found (adjusted HR 1.08; 95% CI, 0.77-1.51). LIMITATIONS, REASONS FOR CAUTION Limitations were the missing data and residual confounding caused by unknown confounders. Furthermore, the control group consisted of all children not conceived by ART and not non-ART children from subfertile mothers. The study was also performed in only singletons and not in the total ART population. WIDER IMPLICATIONS OF THE FINDINGS Type 1 diabetes is a serious disease, affecting human life in several ways, including risk of serious complications, reduced life span and a life-long treatment. Our results are generally reassuring, showing no increase in diabetes in ART children compared to children born after SC after adjustment for relevant confounders. The observation of an association between children born after frozen embryo transfer and type 1 diabetes, although based on subgroup analyses with a limited number of children and modest in size, is however a reason for concern.
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| 7. |
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| 8. |
- Tväråna, Malin, et al.
(författare)
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Visualising complexity and changeability - critical aspects of teaching visual models in economics
- 2023
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Ingår i: EARLI 2023. - Leuven : European Association for Research on Learning and Instruction (EARLI). ; , s. 104-104
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Konferensbidrag (refereegranskat)abstract
- The aim of this presentation is to discuss how models used in social studies teaching can help students grasp the complexity and changeability in economic issues and systems in the context of social science education (SSE). Models are often used in SSE teaching to help students grasp complexity and changeability. However, students often find models difficult to understand and there is a risk that seemingly fixed models do not offer an understanding of the changeability in societal issues. The project investigates students’ conceptions of two different models that are commonly used in SSE (one flowchart and one plot diagram) and what aspects that need to be discerned in order for students to reason in a qualified way about the content illustrated. Results from a phenomenographic analysis of 21 group discussions (with students from both compulsory and upper secondary school) show that the critical aspects identified in part can be understood as model and content specific, but in part as model generic. By comparing the critical aspects for the two different models, it is evident that in order to read both models, aspects pertaining to structure, casual expansion, and human agency are important.
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| 9. |
- Willstrand, Ola, et al.
(författare)
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New certification system for enhanced fire safety of vehicles
- 2018
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Ingår i: Proceedings of 7th Transport Research Arena TRA 2018.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- RISE has initiated and developed a certification scheme for the vehicle industry that will enable manufacturers, operators and service centres (workshops) to certify their fire risk mitigation process. The fire risk management required in the certification is a key safety element, used to identify and evaluate fire hazards. For best results, it is important that manufacturers, operators and service centres are equally dedicated to solve the fire problem. Vehicle fire investigations reveal that design, production, operation and maintenance can all be responsible, however, most important is to ensure that information and experiences from fire incidents and identified fire hazards are linked to relevant personnel, practices, manuals, and quality procedures. The certification cannot guarantee the elimination of vehicle fires, but can ensure that manufacturers, operators and service centres will operate at the front line of vehicle fire safety engineering.
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| 10. |
- Zetterberg, Henrik, 1973, et al.
(författare)
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Neurochemical aftermath of amateur boxing
- 2006
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Ingår i: ARCHIVES OF NEUROLOGY. - : American Medical Association (AMA). - 0003-9942. ; 63:9, s. 1277-1280
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Tidskriftsartikel (refereegranskat)
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