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Comparative Analysis of Video Decoding Algorithms: CUDA vs.Vulkan Compute Shaders on Embedded Platforms : Assessing GPU Compute Frameworks for Embedded Video Decoding
No full textGPU acceleration is essential for meeting the performance demands of modern video processing, particularly on embedded systems. CUDA is a widely adopted framework offering mature tooling and high performance on NVIDIA hardware, but its proprietary nature restricts portability. In contrast, Vulkan provides a cross-platform, low-level API with explicit control over GPU resources, making it a promising candidate for portable, high-performance computing. To evaluate their relative strengths, both in terms of performance and code complexity, a JPEG-based video decoder originally implemented in CUDA was ported to Vulkan and executed on the NVIDIA Jetson AGX Orin platform. Performance measurements were based on two computationally intensive segments of the decoding pipeline, each composed of multiple algorithmic stages. Each segment was benchmarked across four resolutions: 480p, 720p, 1080p, and 1440p. Code complexity was evaluated using established software metrics, including Lines of Code, Cyclomatic Complexity, Halstead Volume, and the Maintainability Index. Vulkan consistently outperformed CUDA in computation time across all tested resolutions, with the performance advantage increasing at higher resolutions and in more memory-intensive stages. In addition to faster execution, Vulkan exhibited more stable timing behaviour, indicating greater runtime consistency. However, this performance and predictability came at the cost of slightly increased code verbosity, reduced maintainability, and a steeper development curve, owing to Vulkan’s explicit design philosophy and less mature tooling ecosystem. These findings highlight a clear trade-off between performance and development effort, offering guidance for developers choosing between CUDA and Vulkan for GPU-accelerated video decoding on embedded platforms
Optimization of Cutting Parameters in Metal Cutting Turning : Using Genetic Algorithms and Gradient Based Optimization
No full textIn metal cutting turning, there is a high chance that the cutting parameters, (cutting speed, cutting depth and cutting feed), used to machine a feature are suboptimal. The reason for this is that there is a gap in numerical methods and software systems to support parameter selection and the high costs of iteratively optimizing the parameters through repeated tests. This thesis investigates how the tool path algorithm and experimental data could be utilized to optimize the parameters for a given feature to be machined. For this, cycle time was extracted from the tool path algorithm and the insert life model could be integrated to better utilize insert life. Two objective functions were derived, with the goal of finding optimal cutting parameters in terms of productivity. The first objective searches for the parameters by minimizing cycle time and includes a time penalty term for insert changes. Whereas the second objective function searches for the parameters that minimize cycle time but is restricted to utilize a maximum number of inserts. The optimization models were tested both theoretically and in a machine test. The theoretical setup showed a significant increase in productivity for the optimized cutting parameters. However, the machine verification showed that the inserts had a high wear, resulting in lower tool life than the prediction, which shows the high physical complexity in metal cutting turning
How is youth crime detected in schools? : A qualitative study on school counselors’ experiences of work and collaboration against youth crime
No full text Tidigare forskning visar att skolkuratorer har en central roll på skolor inom det förebyggande arbetet mot ungdomskriminalitet. Studiens syfte är således att undersöka skolkuratorers arbetssätt, vilka erfarenheter skolkuratorer upplever samt hur de samarbetar med andra aktörer. Denna studie bestod av fyra semistrukrturerade intervjuer med skolkuratorer på gymnasieskolor i en mellanstor stad i norra Sverige. Datamaterialet som samlades från intervjuerna analyserades med hjälp av tematisk analys, som resulterade till fem områden med olika subteman. Vidare i frågan om analysavsnittet så utgår studien från två teoretiska utgångspunkter, vilka är sociala band och socialkulturell teori. Studiens resultat visar att det råder otydlighet kring definition av begreppet ungdomskriminalitet. Det framkommer också av studiens resultat att det finns brist på struktur och riktlinjer när det kommer till skolkuratorernas arbetssätt. Vidare synliggörs att samverkan kan vara personberoende i vissa skolor, vilket kan vara både positivt och negativt i samband med att bekämpa ungdomskriminalitet. Studiens resultat berör även skolkuratorernas handlingsutrymme i frågan om att bygga relation med elever i skolan. I studiens slutsatser framkommer det att skolkuratorer har en stor potential att motverka ungdomskriminalitet. Däremot anses att otyliga riktlinjer och stukturer kan vara en utmaning för skolkuratorer för att kunna arbeta brottsförebyggande. Vidare kan uppges att om skolan skolan får mer struktur och tydliga riktlinjer, kan det leda till att skolan få möjligheten att fånga upp flera ungdomar som riskerar att hamna i brottslighet. Denna studie tar även upp vikten av relationsskapande arbete som ett sätt att motverka ungdomskriminalitet och utanförskap, vilket framkommer tydligt av kuratorernas utsagor.
Från ambulans till akutmottagning: Faktorer som hindrar och möjliggör kommunikationen under överrapportering : En kvalitativ intervjustudie
No full textBakgrund: Kommunikation vid överrapportering från ambulans till akutmottagning är avgörande för patientsäkerheten. Brister i kommunikationen kan leda till informationsförlust, felbehandling och vårdskador. Tidigare forskning har främst fokuserat på akutmottagningens perspektiv, medan ambulanssjuksköterskors erfarenhet är mindre utforskade. Ökad kunskap om deras upplevelser kan bidra till säkrare och mer strukturerade överrapporteringar. Syfte: Studiens syfte är att belysa ambulanssjuksköterskors erfarenheter av faktorer som hindrar och möjliggör kommunikationen under överrapportering till akutmottagningar, utifrån patientsäkerhetsperspektivet. Metod: Studien genomfördes som en kvalitativ intrevjustudie baserad på semistrukturerade intrevjuer med ambulanssjuksköterskor, utvalda genom strategiskt urval kompletterat med bekvämlighetsurval. Det insamlade materialet analyserades med kvalitativ innehållsanalys enligt Graneheim och Lundman (2004). Resultat: Studien visar att kommunikationen under överrapportering påverkas av flera hider och möjliggörande faktorer. Hindrande faktorer var bullrig miljö, avbrott, brist på struktur, sekretessproblem och hög arbetsbelatsning. Dessa ledde ofta till informationsförlust och risker för patientsäkerheten. Möjliggörande faktorer var aktivt lyssnande, tydlig struktur genom verktyg som SBAR, närvarande ledarskap och gott samarbete mellan yrkesgrupper. En ostörd och samlad överrapportering upplevdes som avgörande för en säker överrapportering. Slutsats: Effektiv kommunikation under överrapportering kräver tydliga rutiner, stödjande vårdmiljö och strukturerade verktyg. Genom att minska avbrott, stärka sekretess, främja aktivt lyssnande och erbjuda interprofessionell träning kan kommunikationsprocessen förbättras och därmed öka patientsäkerheten. Studien betonar vikten av att se kommunikationsbrister som systemfel enligt Swiss Chesse-modellen, och föreslår att framtida insatser bör fokusera på organisatoriska förbättringar snarare än enbart individens argerande.
Daylight in a circular and sustainable built environment
No full textAs the built environment moves towards more sustainable and circular practices, the role of daylight in these strategies remains an underexplored area of research. This workshop will explore how daylighting principles can contribute to a Circular and Sustainable Built Environment, such as through the reuse of buildings, façade components, windows, and glazing, while considering relationships and impacts on daylight performance and qualities, design process, energy use, and human comfort and health. Recent research has started bridging this gap, demonstrating how solar-responsive and adaptable façades can optimize daylight while enhancing the circularity of facades in urban environments undergoing urbanization and densification. However, further investigation is needed to understand the interaction between daylight and circular construction practices, including adaptive reuse, reuse of building components, glazing, and material recovery. Objectives Identify various daylight and circular strategies and their interaction/integration. Explore the influence of coupled daylight and circularity strategies on building performance, visual comfort, and health effects. Discuss daylight properties and qualities of reused buildings, façade components, and glass versus new high-performance buildings and components. Identify the next steps and define possible outcomes.DLA Annual Conference 2025, Parallel session H, presentation of the topic and workshop with registered participantsQC 20250611</p
Black Friday: Rea-liteten bakom köpen : En kvantitativ studie om hur olika faktorer driver konsumenters köpmotivation
No full textSyfte: Denna studie syftar till att undersöka hur faktorerna utilitarisk och hedonisk motivation, attityder, samt FOMO (fear of missing out) påverkar konsumenters köpmotivation under Black Friday. Teori: Studien utgår från ett teoretiskt ramverk som kombinerar utilitarisk och hedonisk motivation, attityder samt FOMO. Tillsammans belyser dessa teorier hur rationella och emotionella drivkrafter påverkar konsumentens köpmotivation under Black Friday. Ramverket bidrar till en djupare förståelse för samspelet mellan individuella drivkrafter och yttre påverkan i samband med konsumtionshögtiden. Metod: Studien baserades på en kvantitativ metod med en deduktiv ansats och en positivistisk forskningsfilosofi. Data samlades in genom en enkätundersökning som distribuerades via sociala medier, där totalt 189 personer deltog. Analysen genomfördes med hjälp av korrelationsanalys, univariat analys och flera regressionsanalyser. Korrelationsanalysen användes för att undersöka samband mellan de oberoende variablerna, medan den univariata analysen beskrev fördelningen av svaren. Regressionsanalyserna användes för att testa vilka faktorer som har störst påverkan på konsumenters köpmotivation under Black Friday. Resultat: Resultaten visade att hedonisk motivation, attityder och FOMO hade ett starkt och signifikant samband med köpmotivationen under Black Friday. Dessa faktorer visade sig vara mest avgörande för att förklara varför konsumenter motiveras att handla under denna konsumtionshögtid. Utilitarisk motivation som enskild variabel visade däremot inte något statistiskt signifikant samband. Analys och slutsatser: Analysen visade att emotionella och psykologiska faktorer så som hedonisk motivation, attityder och FOMO har en större påverkan på konsumenters köpmotivation under Black Friday. Än vad mer rationella och funktionella faktorer som utilitarisk motivation har. Detta tyder på att konsumentbeteendet under Black Friday till stor del drivs av känslor, upplevelser och social påverkan. Studien bidrar till ökad förståelse för vad som motiverar köpbeslut under konsumtionshögtiden, vilket kan vara värdefullt för företag som vill utforma effektiva marknadsföringsstrategier. Purpose: This study aims to examine how utilitarian and hedonic motivation, attitudes, and FOMO (fear of missing out) influence consumers’ purchase motivation during Black Friday. Theory: This study is based on a theoretical framework that combines utilitarian and hedonic motivation, attitudes and FOMO. Together, these theories highlight how rational and emotional drivers affect consumers’ purchase motivation during Black Friday. The framework contributes to a deeper understanding of the interaction between individual drivers and external influences in the context of this consumption-oriented event. Method: A quantitative method was employed, based on a deductive approach and a positivist research philosophy. Data were collected through a survey distributed via social media, with a total of 189 respondents. The analysis consisted of correlation analysis, univariate analysis and several regression analyses. The correlation analysis was used to explore relationships between the independent variables, while the univariate analysis described the distribution of responses. The regression analyses tested which factors had the greatest impact on consumers’ purchase motivation during Black Friday. Results: The results showed that hedonic motivation, attitudes and FOMO had a strong and significant relationship with purchase motivation during Black Friday. These factors were found to be the most influential in explaining why consumers are motivated to purchase during this consumption event. Utilitarian motivation, on the other hand, did not show a statistically significant relationship when examined as an individual variable Analysis and conclusions: The analysis indicated that emotional and psychological factors, such as hedonic motivation, attitudes and FOMO, have greater impact on purchase motivation during Black Friday than more rational and functional factors like utilitarian motivation. This suggests that consumer behavior during Black Friday is highly driven by emotions, experiences and social influence. The study contributes to a better understanding of what drives purchase decisions during this consumption event, which may be valuable for companies aiming to design effective marketing strategies.
The Persuasive Power of FOMO : A Study on Instagram Advertising Targeting Generation Z
No full textSocial media platforms such as Instagram have become a key instrument formarketing purposes. As competition rises not only does the volume ofadvertisements increase, but so too does the variety of persuasive tactics usedto influence consumer purchasing decisions. This study aims to understand thepsychological phenomenon called “FOMO” and the persuasion effectivenesswhen it is used in advertisements on Instagram to target younger audiences.Grounded in the Elaboration Likelihood Model (ELM) and FOMO theory, adeductive approach was adopted utilizing a multi-method with a quantitativeexperiment in the form of a survey. These were distributed to Instagram usersbetween the ages of 18-30 years old. The hypothesis and conceptual modelwere tested using relevant statistical analysis techniques. The results showedno statistically significant difference in persuasion between the control andFOMO group. However significant differences can be observed in the differentprocessing styles within the ELM. These findings offer theoretical support forthe ELM framework and extend them to social media, especially in the contextof Instagram and generation Z, while suggesting boundary conditions of theimpact of FOMO in the field of marketing. The study contributes to theadvertising world and provides insights for managers and marketers aiming tooptimize their marketing messaging towards generation Z. Through theexperimental nature of this study, it contributes to the research in marketingand psychology by combining FOMO with the ELM and Instagram
APIS project final report
No full textThere is strong pressure to develop a drone industry. Investments are made by the industrial partners but there is also drone strategies at EU and national policy level. One reason is to address challenges for urbanization and climate impact from transportation. In addition, the EU: s transport commissioner says "We believe that if our (drone)strategy is implemented properly, the drone market could be worth 14.5 billion euros ($15 billion) by 2030. It could also create 145,000 new jobs in the European Union”. The key word here is PROPERLY. Managing noise from drone transport systems will be crucial for societal acceptance. If noise and disturbances are not adequately considered, there is a risk that the realization of these innovations may be delayed or hindered by constraints in planning and approval processes or result in restrictions on established drone services. Through the development of a simulation platform SAFTu, and a framework for implementation aspects of drones in an urban setting the APIS project provides tools and methods for addressing drone noise and annoyance, properly. The project is carried out with a broad approach and the project groups have engaged with stakeholders in discussions and interviews with the Swedish Transport Administration, Sweden's’ municipalities and regions, the Environmental Protection Agency, LFV, manufacturers, and interest organizations. One key delivery of the project is the SAFTu noise prediction software. This tool enables the calculation of the ground sound pressure levels from UAV (Urban Aerial Vehicle) flights. Noise level contours based on different noise metrics can be determined and displayed on a map. The number of inhabitants exposed to noise levels within a sound level band can be presented in histogram form. A framework for determining UAV sound source models and implementing such models into SAFTu is established. Vehicle noise source models based on field test noise data from two delivery UAVs have been implemented in the software. Two scenarios for use-cases in the Stockholm region and in Jämtland county are addressed, representing potential implementations of UAM (Urban Air Mobility) for transport of goods. SAFTu is used to assess noise levels and in one case the number of inhabitants exposed. Two scenarios for UAM implementation at different scales are analysed with respect to trade-offs between goal achievements and conditions for innovation within a city, including its citizens. Both scenarios have advantages and disadvantages. This complex interplay is described in the conceptual framework for the implementation of UAM (WP1). Before UAM introduction it is recommended that noise mapping simulations are used to evaluate noise effects related to choice of UAV type and operational settings and to optimize flight routes. Simulated results can also be used to communicate the effect of drone services and noise control measures to the affected citizens and for training and awareness purposes fostering competence and acceptance with actors and citizens. It should be noted that the computation of noise from UAV flights on the ground could not be handled by current aircraft noise mapping standards (like the ECAC Doc.29 method). So, to establish possible future UAM noise footprint new tools like SAFTu are needed. The APIS project aims to raise awareness, develop knowledge, and provide methods that will support stakeholders in the development and implementation of drones in urban environments. Given the project findings and previous experiences, it is also observed that consequent noise regulations and guidelines for drone operations are needed. To support the introduction of UAM in Sweden more research in this area is needed both regarding accurate noise modelling and analysis methodology and methods to minimize acoustic annoyance.QC 20250611APISFLYT 365INFR
Magnetic resonance-derived hepatic uptake index improves the identification of patients at risk of severe post-hepatectomy liver failure
No full textBackground: Post-hepatectomy liver failure (PHLF) is a leading cause of mortality after major liver resection. Accurate preoperative risk assessment is essential, yet current methods have limitations. Gadoxetic acid-enhanced MRI (Gd-EOB MRI) enables both morphological and functional evaluation of the liver. The aim of this study was to evaluate the efficacy of the hepatic uptake index (HUI) obtained from routine preoperative Gd-EOB MRI for identifying patients at risk of severe PHLF. Methods: This observational retrospective multicentre study included 292 patients who underwent major hepatectomy between 2010 and 2020 in Sweden, Denmark, and Finland. Preoperative Gd-EOB MRI was performed for each patient and the HUI, hepatic uptake index of the standardized future liver remnant (sFLR-HUI), and Model for End-Stage Liver Disease Version 3 (MELD 3) score were evaluated. Statistical analyses included logistic regression and receiver operating characteristic (ROC) curve assessment to determine cut-off values and discriminative accuracies for severe PHLF (International Study Group of Liver Surgery grades B and C). Results: Among the 292 patients, 25 (8.6%) developed severe PHLF. Patients with severe PHLF had significantly lower HUI and sFLR-HUI values (P < 0.001). The HUI demonstrated superior discriminative performance for severe PHLF (area under the curve (AUC) 0.758) compared with volume-only assessments, such as the standardized future liver remnant (sFLR) (AUC 0.628). Combining the HUI with the MELD 3 score improved performance further (AUC 0.803). Conclusion: The HUI obtained from routine Gd-EOB MRI outperforms volume-based biomarkers (sFLR) for identification of patients at risk of severe PHLF. Incorporating image-derived functional assessments, such as the HUI, with independent biomarkers, such as the MELD 3 score, may optimize preoperative risk stratification for severe PHLF and improve outcomes after major hepatectomy
Comparative oxidation behavior of columnar and equiaxed Cr2AlC coatings
No full textThe oxidation behavior of columnar and equiaxed Cr2AlC coatings in air at 990 °C is studied. During the transient heating-up period to 990 °C the two coating morphologies exhibit different oxidation behavior. In columnar coatings, faster Al diffusion along column boundaries, triple junctions, and intercolumnar pores leads to the formation of metastable alumina polymorphs, resulting in rapid oxidation. In contrast, equiaxed coatings exhibit slower oxidation kinetics due to limited Al mobility, leading to direct formation of passivating α-(Al,Cr)2O3 through oxidation of Cr and Al at the surface