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Solar Power Potential in Africa : A Case Study on Cost Reduction in a Malian Household Through Photovoltaic Solar Power and Lithium-Ion Battery Storage
No full textThis study explores the potential for PV solar power and battery storage to reduce energy costs in a typical Malian single-family household, highlighting significant cost savings and improved energy reliability. The high solar irradiance throughout the year makes solar power viable for household energy needs. However, most electricity is consumed at night due to air conditioning, with an annual consumption of 12,504 kWh. Cost models for solar power plants and battery energy storage systems, including installation, were developed. Cost parameters were reviewed using the latest literature, distinguishing between current and future cost trends, referred to as Case I and Case II, respectively. Additionally, a feed-in tariff of 0.04 per injected kWh of electricity into the AC mains was considered. The annual return in USD and the return on investment were considered as economic parameters. A small solar power plant with a peak power of up to 3 kW can achieve a high ROI between 70% and 100%. Due to reduced future cost prospects, this ROI could increase to 90% to 130%. However, such a plant can only reach a maximum self-sufficiency of about 40%, as most of the electricity is consumed during nights. A 4 kW power plant can achieve a self-sufficiency of about one-third for an ROI of 57% to 82%, costing approximately 1760. When using battery energy storage, a self-sufficiency of 95% has been targeted. With battery storage, the maximum ROI varies from 22.5% to 32.0% with an investment cost of about 13,139.CC BY 4.0</p
Könsskildring i samtida datorspel: Stereotyper, objektifiering och representation
No full textA content analysis of games released in 2024 was made with the goal of finding any potential changes in gender portrayal, specifically looking at gender diversity, stereotypical traits in male and female characters and objectification of female characters. The objectification of female characters is also compared to a study done in 2002 with the same method. Our study shows that the objectification of female characters has changed since the study made in 2002 in that there is less revealing clothing and more natural looking body types 2024. Stereotypical traits as well as diversity have been analysed by also doing a content analysis for games released in 2014. Stereotypes in characters does not seem to have a significant difference between 2014 and 2024 and gender diversity actually seems to have decreased since 2014.En innehållsanalys av datorspel som släpptes år 2024 har utförts med syftet att ta reda på ifall det hänt någon förändring inom könsskildring i datorspel. Specifikt analyseras förändringen av könsrepresentation, stereotypiska karaktärsdrag i karaktärer och objektifiering av kvinnokaraktärer . Objektifieringen av kvinnliga figurer jämförs med en studie från 2002 som har samma metod. Resultatet visar att objektifieringen av kvinnliga karaktärer har ändrats sedan 2002 då de modernare karaktärerna har mer täckande klädsel och mer naturliga kroppstyper. Stereotypiska karaktärsdrag hos karaktärer och könsrepresentation har analyserats genom att också göra en innehållsanalys av datorspel som släpptes 2014. När det gäller stereotyper i datorspelsfigurer så verkar det inte skett en större skillnad mellan 2014 och 2024 och mångfalden av kön bland karaktärer verkar faktiskt ha minskat sedan 2014
Temporal Changes in Glacier Ice Motion : A Comparison Between Alaska and Svalbard(1985–2022) with a Focus on Glacier Size and Climate
No full textDen här studien undersöker förändringar i glaciärers isrörelse på Svalbard och i Alaska under perioden 1985–2022, med fokus på hur glaciärstorlek och regionala klimatförhållanden påverkar rörelsemönster. Genom analys av satellitbaserade hastighetsdata och glaciärers area framkommer att isrörelsen generellt har ökat i Alaska, särskilt för större glaciärer, medan en minskning observerats på Svalbard. Resultaten visar att ett varmare, maritimt klimat i Alaska har ökat smältvattenproduktionen och därmed bottenglidningen, vilket ökar isrörelsen. På Svalbard däremot, där ett kallare och torrare klimat än i Alaska och förekomsten av Surge-glaciärer leder till minskad rörelse. Mindre glaciärer i båda regionerna uppvisar en tendens till minskad rörelse, främst på grund av uttunning och minskad drivspänning. Studien identifierar även faktorer som glaciärens lutning, underlag och komplexitet som viktiga komponenter för att förstå variationer i isrörelse. För framtida forskning rekommenderas en mer detaljerad analys av lokala förhållanden såsom lutning och berggrund. Övergripande visar studien att förändringar i isrörelse är en komplex interaktion mellan klimatförändringar och glaciärers fysiska egenskaper.This study investigates changes in glacier flow on Svalbard and in Alaska between 1985 and 2022, focusing on how glacier size and regional climate conditions influence movement patterns. Analysis of satellite-derived velocity data and glacier area reveals that glacier flow has generally increased in Alaska, particularly among larger glaciers, while a decrease has been observed on Svalbard. Results indicate that a warmer, maritime climate in Alaska has increased meltwater production, enhancing basal sliding and thereby glacier movement. Conversely, a colder, drier climate and the prevalence of surge-type glaciers on Svalbard have contributed to a reduction in flow. Smaller glaciers in both regions tend to show reduced movement, primarily due to thinning and decreased driving stress. The study also highlights glacier slope, bedrock type, and system complexity as important factors in explaining variations in flow behavior. Future research is recommended to include more detailed analyses of local factors such as slope and geology. Overall, the results demonstrate that changes in glacier flow are a complex interaction between climate change and the physical properties of glaciers
Measuring the Invisible : A literature review on Pain Assessment in the Emergency Department from a Nursing perspective
No full textBakgrund: Smärta är en av de vanligaste orsakerna till att patienter söker vård akut och en korrekt smärtbedömning är avgörande för att säkerställa snabb och adekvat vård. Sjuksköterskans roll i att tolka och prioritera patientens smärta är komplex och påverkas av en rad faktorer. Trots befintliga smärtskattningsinstrument och standardiserade triagesystem visar forskning att smärta ofta underskattas eller förbises, vilket kan leda till bristfällig smärtlindring och negativa utfall. Syfte: Syftet var att utforska faktorer som påverkar hur sjuksköterskor bedömer smärta hos patienter på akutmottagningen. Metod: En integrativ litteraturöversikt med induktiv ansats. En systematisk litteratursökning utfördes i databaserna PubMed och CINAHL. Totalt inkluderades 17 artiklar. Resultat: Analysen identifierade tre huvudsakliga teman: (1) Underlag för smärtbedömning, där både subjektiv självskattning och objektiva parametrar visade sig ha styrkor och begränsningar. (2) Smärtans roll i triagen är central, men hanteras inkonsekvent. Ibland justerar sjuksköterskor patientens självskattning för att påverka prioriteringen. (3) Barriärer och förbättringsåtgärder. Tidspress, kommunikationsutmaningar och brist på standardiserade riktlinjer framstod som hinder för en rättvis och effektiv smärtbedömning. Slutsats: Smärtbedömning inom akutsjukvården är en komplex process som påverkas av både individuella och strukturella faktorer. Förbättrade riktlinjer angående smärtskattning, ökad utbildning om smärtbedömning och implementering av standardiserade protokoll kan bidra till mer jämlik vård. Det är viktigt att uppmärksamma smärtbedömning hos patienter med kognitiv svikt och att minska subjektiva bias i triagebeslut
Prehistory in 100 Years of Educational Films : Representations of Gender Roles and Relations in Swedish Schools
No full textTeaching about Nordic prehistory has a long tradition in Sweden and films about this period in history have been available to schools since the early 1900s. Our knowledge of prehistory is based on archaeological science, but there is a lack of studies showing the relation between research and knowledge of prehistory in educational films. This study of films about Nordic prehistory analyses the transformation in the way women, men and children have been presented. The results of the study show how men have been visualised as having important roles while women have been responsible for tasks close to home, but in recent years a certain change can be seen in this role distribution. The study also shows how the focus has shifted from the Stone Age man to the Stone Age girl and how children have gone from being insignificant to being the main characters in the films..CC-BY 4.0</p
Flame Detectors in Gas Turbine Enclosures : A study on different flame detectors for various fuel mixtures
No full textAs society increasingly transitions to renewable energy, Siemens Energy is exploring the possibility of using mixtures of methane and hydrogen gas as fuel in their gas turbines. To ensure effective fire detection, a system capable of alerting to both hydrogen and methane fires is required. Flame detectors, which are part of this system, analyze the wavelengths emitted during fires. This study focuses on the performance of various flame detectors under these conditions, with particular attention to their technical and functional requirements as well as the standards they must meet. The study uses a literature review to compile and analyze data from previous studies and tests conducted by subcontractors and manufacturers. The results show that most of the flame detectors examined meet the necessary requirements for operating temperature, materials, field of view, and immunity to false alarms. Additionally, most detectors comply with important standards such as ATEX, IECEx, EN 54-10, and CE, ensuring their safety and reliability in explosive environments. Tests conducted by the manufacturers revealed that UV, IR, and UV/IR detectors all demonstrated varying levels of effectiveness in detecting fires involving methane, hydrogen, and mixtures of these two fuels. While the performance varied among individual detectors, all types showed sufficient capability to be considered for applications requiring reliable fire detection. The report emphasizes the importance of selecting the right flame detector based on specific application needs and fuel mixtures. The flame detector with the nickname Mario is recommended for further testing due to its reliable performance across all criteria. Siemens Energy should continue testing to ensure its reliability, as practical tests are the ultimate verification. Despite the absence of complete tests, numerous tests have been conducted on this detector compared to others. This detector meets all studied standards except for VdS, operates from -55 to +85 °C, is made of stainless steel, and has a 90° field of view. Detailed test results are summarized in Table 9.1
Teaching grammar – "sort of like a maths lesson" : Newly graduated Swedish teachers'conceptions of teaching grammar
No full textThe aim of this study is to analyse newly graduated Swedish L1 teachers’ conceptions of teaching grammar. The data is collected from three semi-structured interviews with newly graduated Swedish L1 teachers and is then compared to two curricula and two textbooks for Swedish L1 through triangulation. The results are then analysed through thematic analysis and discussed through Dewey’s and Freire’s perspectives of learning by doing and communicative teaching. The results indicate that the participating teachers favour contextualised methods of teaching grammar even though they rarely employ it in practice, instead opting for a traditional way of teaching grammar. Furthermore, the teachers imply that they would be open to utilising contextualised ways of teaching grammar more as they become more comfortable teaching. Previous research shows that traditional grammar teaching is ineffective compared to a contextualised approach and provides students with less opportunity for self-agency. The overall findings of the study highlight the importance of newly graduated teachers being given support in their new profession through collegial learning, support from management and textbooks to make sure their teaching practice is scientifically up to date
Nurses’ experiences of child participation at a paediatric ward in the Seychelles
No full textBakgrund: Synen på pediatrisk omvårdnad och barnens samhälleliga roll har senaste århundradet förändrats. Barn har gått från att ses som ett objekt till att respekteras som egna individer. Det har visats betydelsefullt att ge barn möjlighet att delta i sin vård då det är väsentligt för barnets upplevelse och följsamhet. Barns rätt till delaktighet i vården styrs av nationell samt internationell lagstiftning, trots det påvisas det svårigheter i att implementera barns rättigheter i praktiken. Motiv: Ett ökat behov av kunskap om hur sjuksköterskor upplever barns delaktighet anses nödvändigt för att utveckla och förbättra vården för barnen. Syftet var att utforska Seychelliska sjuksköterskors erfarenheter av att möjliggöra barns delaktighet i sin vård på en pediatrisk vårdavdelning. Metod: En kvalitativ semistrukturerad intervjustudie utfördes med åtta sjuksköterskor på pediatriska vårdavdelningen på Seychellerna. Intervjuerna analyserades utifrån en kvalitativ innehållsanalys som resulterade i tre kategorier med åtta tillhörande subkategorier. Resultat: De tre huvudkategorierna benämndes: Attityder till barns delaktighet, Strategier för att möjliggöra barns delaktighet samt Verksamhetens utvecklingsmöjligheter ur ett barnrättsperspektiv. Beroende på sjuksköterskans attityd till barns delaktighet varierade engagemanget för att involvera barnet. Somliga ansåg delaktighet som självklart då det resulterade i ett tryggt och stärkt barn, medan andra såg det som meningslöst då barnet inte förstod eller hade något att säga till om. Det framkom även att hinder för barns delaktighet kunde bero på verksamhetens förutsättningar. Konklusion: Det framkom delade meningar om till vilken grad ett barn ska göras delaktig, om över huvud taget, men en majoritet av sjuksköterskorna önskade stärka och utveckla barns delaktighet då det ansågs främja ett gott samarbete likväl som tillgodose barnets rättigheter.Background: Paediatric nursing and the societal role of children have evolved during the last century. Children have gone from being objectified to being recognized as respected individuals. Enabling child participation in their healthcare is crucial, since this has been shown to play a key role in the child’s experience and increases compliance. Although a child’s right to participate is governed by legislation, there are still challenges in implementing these in clinical practice. Motive: A deeper understanding of nurses’ experiences regarding children’s participation is necessary to develop and enhance paediatric care and nursing. Aim: The aim was to explore Seychellois nurses’ experiences of enabling children’s participation in their healthcare at a paediatric ward. Methods: A qualitative, semi-structured interview study was conducted with eight nurses at the paediatric ward in the Seychelles. The interviews were analysed using a qualitative content analysis, resulting in three main categories and eight subcategories. Result: The three main categories were: Attitudes towards child participation, Strategies to enable child participation, and Organizational development opportunities with a focus on a children’s rights perspective. Nurses’ dedication towards enabling child participation varied depending on their attitudes. Some regarded participation as obvious with the belief it resulted in a safe and empowered child. Others considered participation meaningless, reasoning that the child did not understand or were to have a say in the matter. Organizational conditions played a part in enabling child participation as well. Conclusion: There were divided perceptions regarding the extent to which a child should be able to participate, if at all. However, most nurses expressed a desire to develop and encourage child participation, as it promoted better collaboration as well as endorsing children’s rights.
Achieving energy efficiency in industrial manufacturing
No full textThis paper explores the use of digital technology stages and knowledge demand types for achieving energy efficiency. Digital technology stages are the steps toward developing an intelligent and networked factory: computerization, connectivity, visibility, transparency, predictive capacity, and adaptability. Knowledge demand types refer to the knowledge and skills needed to implement energy management through technical, process, and leadership knowledge. Empirical data were collected from a critical single case study at an industrial manufacturing company. The study made two significant contributions. Firstly, it identifies fourteen challenges and improvement potentials when working with energy monitoring, evaluation, and optimization, demonstrating the critical role of digital technology stages and knowledge demand types. Secondly, the study presents a conceptual framework indicating how companies could overcome pitfalls and enhance energy efficiency by combining digital technologies and knowledge demands. Future work will include technical implementations and its connection to knowledge management
A validation protocol for 177Lu-SPECT image quantification as a basis for multi-centre kidney dosimetry
No full textObjective. Multicentre studies in molecular radiotherapy face challenges in ensuring the comparability of dosimetry results. The aim of this study was to develop a validation protocol to achieve equivalent Lu-177-SPECT quantification across centres, consisting of a test exercise in combination with an action level. Approach. Lu-177-SPECT/CT imaging of 3D-printed kidney phantoms with non-uniform activity distributions was conducted at five hospitals in Sweden and the UK. In total, 12 quantification systems (QSs) were included, where a QS was defined as the combination of a given camera system, reconstruction method and image-analysis method. The accuracy of image-based estimates of the activity concentration was investigated for three approaches to multicentre dosimetry: one site-specific, and two variants of centralised approaches. For the site-specific approach, the reference value was blinded to the evaluating operators. Prior to the evaluation, the participants agreed on an action level, specified as an obtained deviation larger than ±10% from the reference value. Sites responsible for a QS that yielded larger deviations, and therefore did not comply, were required to present an action plan, i.e., a plan for further method optimisation. Main results. For the site-specific approach, deviations larger than 10% were obtained for six out of 12 QS (range -11% to +27%). Action plans were presented for these QS and was implemented by one site (two QS). For the two variants of centralised approaches, where nine QS were included in total, deviations of within 10% were obtained for nine and seven QS, respectively. Significance. A quantification test combined with an action level can serve as an initial validation to enable further development and to achieve equivalent Lu177-SPECT quantification across sites