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Fast electromagnetic and thermal modelling of foil windings in power electronics magnetic components
No full textDe trend naar gewichts- en volumevermindering van elektromagnetische componenten
in vermogenselektronica wordt mogelijk door hogere schakelfrequenties. Deze
behouden de energieconversie-efficiëntie, maar zorgen voor thermische beperkingen.
Daarom zijn compacte en nauwkeurige modellen nodig die elektromagnetisch en
thermisch gedrag correct weergeven. Dit onderzoek ontwikkelt en valideert modellen
via eindige-elementenanalyse (FEA) van een zelfgebouwde EE-kerntransformator met
koperen foliewikkelingen. Deze modellen ondersteunen ontwerp en optimalisatie in
vermogenelectronica. De methode van eindige elementen (FEM) wordt toegepast op
een gesimuleerd model dat een maximale fout van 5% vertoont, met sterk verminderde
rekentijd en geheugengebruik ten opzichte van fijnmazige modellen. Validatie gebeurt
via infraroodmetingen op de transformator in een full-bridge CLLLC-omvormer met
synchrone gelijkrichting in een 6,6 kW on-board charger. De gemeten waarden weken af
van de verwachtingen, waardoor de validatie beperkt bleef. De scriptie bespreekt
beïnvloedende factoren en stelt homogenisatietechnieken voor ter verbetering van de
efficiëntie. Elektromagnetische eigenschappen worden gekarakteriseerd via RLC-metingen. De grofmazige modellen behalen een gemiddelde thermische
nauwkeurigheid van 96% en een geheugenefficiëntieverbetering met een factor 28,
gemiddeld over alle zelfgebouwde simulatiemodellen
Future Burden of Heat on Mortality in Flanders: A Modeling Approach Accounting for Climate and Population Dynamics
No full textThe increased frequency of extreme heat and heat waves is directly linked to global warming. These phenomena are mostly observed in urban agglomerations that retain a relatively large amount of heat and cause heat stress among people over 65 years of age and young children, resulting in excess mortality. Mapping the health impact of heat, now and in the future, is an important step for preventive climate health policy and aims to identify priority locations and vulnerable target groups, thus allowing policymakers to take effective actions. Unlocking climate health data can increase support for taking climate action. This paper presents the potential impact of heat on the health of the Flemish population under different scenarios, combining health, climate, and land use models in space and time. One corresponds to the actual situation according to demographics and daily temperature, and the two others correspond to projections for the year 2050 that are aligned with the Shared Socioeconomic Pathway scenario SSP5-\documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}\end{document}8.5. In the first scenario for 2050, where only the effect of climate change is considered, the number of heat-related deaths per summer increases by about three times compared to the actual scenario. In the second scenario for 2050, population projections and the spatial policy plans for 2050 are additionally considered, resulting in a doubling of expected deaths due to heat stress compared to the climate-only scenario. The findings of this study indicate that population growth and densification are important factors in assessing heat-related mortality under climate change scenarios in Flanders. This underscores the need for coordinated efforts between public health initiatives and spatial planning strategies to mitigate the impact of heat stress on the Flemish population.Acknowledgements The study was funded by the Department of Care of the Flemish Government
De inzet van digitale innovaties en/of sensorische modellen om sensorische overstimulatie en mogelijke negatieve impact op mentaal welzijn te verminderen
No full textEvaluating the effects of aqueous extracts from blueberry leaves, berries, and biochar on seedling growth of Arabidopsis thaliana and crop species
No full textPlantenresten uit de blauwe bessenteelt worden vaak weggegooid, terwijl ze waardevolle stoffen zoals fenolen en flavonoïden bevatten die plantengroei kunnen stimuleren. Deze studie onderzocht het groeibevorderend effect van drie waterige extracten: biochar-extract (BCE), bladextract (LE) en onrijp bessenextract (UBE). Drie bioassays werden uitgevoerd: (1) een 96-wells plaatassay met Arabidopsis thaliana, (2) een petrischaaltest met sla en radijs via zaadpriming en continue blootstelling, en (3) een voorlopige potproef met radijs.
In de 96-welltest leidde BCE (0,5–2%) tot een dosisafhankelijke stimulatie van versgewicht en wortellengte, met optimale effecten bij 0,5–1%. In de petrischaaltest (BCE 0,5–1,5%, UBE en LE 0,0025–0,01%) verhoogde zaadpriming het versgewicht, terwijl continue blootstelling neutrale of negatieve effecten gaf. In de potproef, met toepassing van BCE (0,5%, 1%) en LE/UBE (0,01%, 0,05%), werden geen significante verschillen gevonden door suboptimale omstandigheden.
De resultaten tonen aan dat BCE, LE en UBE potentie hebben als biostimulanten, afhankelijk van concentratie en toedieningswijze. Verder onderzoek is nodig om de toepassing te optimaliseren en de werking beter te begrijpen
Recurrent Events Analysis of MASTER DAPT Total Ischemic and Bleeding Events After Abbreviated vs Prolonged DAPT in HBR Patients
No full textBACKGROUND The effect of dual antiplatelet therapy (DAPT) duration on total events in patients at high bleeding risk (HBR) after percutaneous coronary intervention (PCI) is unclear. OBJECTIVES This study aimed to evaluate an abbreviated (median duration, 34 days) vs prolonged (median duration, 192 days) DAPT regimen on total events in 4,579 HBR patients from the MASTER DAPT (Management of High Bleeding Risk Patients Post Bioresorbable Polymer Coated Stent Implantation With an Abbreviated Versus Standard DAPT Regimen) trial. METHODS The MASTER DAPT coprimary outcomes at 335 days were as follows: 1) net adverse clinical events (NACEs), the composite of all-cause death, myocardial infarction (MI), stroke, and Bleeding Academic Research Consortium (BARC) 3 or 5 bleeding events; 2) major adverse cardiac and cerebral events (MACCEs), including all-cause death, MI, and stroke; and 3) major or clinically relevant nonmajor bleeding (MCB, type 2, 3, or 5 BARC bleeding). The differences between abbreviated and prolonged DAPT regimens were investigated using the Prentice, Williams, and Peterson model to account for recurrent events. Additional analyses were performed using the Andersen-Gill and Poisson incidence rate models. RESULTS In the abbreviated DAPT (n = 2,295) arm of the trial, 214 NACEs occurred in 172 patients, compared with 227 NACEs in 182 patients in the prolonged DAPT arm (n = 2,284; HR: 0.95; 95% CI: 0.78-1.16; P = 0.64). A total of 156 MACCEs in 138 patients were observed in the abbreviated DAPT group compared with 160 MACCEs in 138 patients in the prolonged DAPT arm (HR: 0.96; 95% CI: 0.76-1.20; P = 0.69). Fewer total MCBs were observed in the abbreviated DAPT group (180 MCBs in 148 patients) compared with the prolonged DAPT group (240 MCBs in 211 patients, HR: 0.78; 95% CI: 0.64-0.94; P = 0.011). Abbreviated DAPT patients had significantly fewer total cerebrovascular accidents and fewer total strokes compared with the prolonged DAPT group (34 events in 32 patients, HR: 0.51; 95% CI: 0.28-0.91; P = 0.023; and 25 events in 24 patients, HR: 0.49; 95% CI: 0.25-0.98; P = 0.04, respectively). One MACCE in every 5 occurred after a bleeding event, and 1 bleeding event in every 25 occurred after a MACCE, thus emphasizing bleeding as a sentinel event. CONCLUSIONS A 1-month DAPT duration was associated with similar total NACEs and MACCEs and reduced total bleeding risk compared with prolonged DAPT. Providing a more comprehensive assessment of the total clinical burden, these findings support the use of an abbreviated duration of DAPT after PCI in HBR patients. (Management of High Bleeding Risk Patients Post Bioresorbable Polymer Coated Stent Implantation With an Abbreviated Versus Standard DAPT Regimen [MASTER DAPT]; NCT03023020) (JACC. 2025;86:485-498) (c) 2025 Published by Elsevier on behalf of the American College of Cardiology Foundation.The MASTER DAPT trial is conducted with support from Terumo. The study sponsor, the European Cardiovascular Research Institute (ECRI), Rotterdam, the Netherlands, a nonprofit organization, received grant support from Terumo for the conduct of the MASTER DAPT trial. The ECRI outsourced to the Clinical Trial Unit, Bern, Switzerland all statistical analyses of the present paper under a research contract agreement between the 2 institutions. None of the authors received personal or institutional
This paper is dedicated to the memory of Dr Tiziana Zaro, who greatly contributed to the MASTER DAPT study, as well as many other academic trials, and who taught us love for cardiology and enthusiasm for research
Numerical and analytical appraisal of innovative tubular perfobond shear connector
No full textShear connectors are well known for their importance in ensuring monolithic behavior in composite beams. Due to this fact, both industry and academia are continuously seeking improvements and innovative solutions to enhance the structural performance of composite structures. Thus, this paper proposes a new type of perfobond shear connector with a tubular cross-section (TPC), an innovative design aimed at improving mechanical performance, particularly in terms of ductility and ease of manufacturing, utilizing commercially available tubular cross-sections. To investigate the feasibility and performance of the proposed connector, numerical models of push-out tests were carried out based on conventional Perfobond connectors. The outcomes demonstrated that the TPC offers excellent stiffness, shear resistance, and ductility. It was observed that concrete strength, steel grade, and the geometric configuration of the tubular cross-section significantly influence the mechanical behavior of the TPC. In addition, compared to the conventional perfobond connector, the proposed connector showed increases of up to 7.5 % in resistance and 169 % in ductility, respectively. Furthermore, an analytical formulation was developed based on the identified failure modes to predict the connector resistance, showing satisfactory agreement with numerical results. Since TPC is as resistant as the conventional perfobond and also presents superior deformation capacity, it can be employed not only in buildings but also in bridges.This study was supported by the Special Research Fund (BOF) BOF20BL03, CAPES (Finance code 001), CERG, CNPq (305047/2023–0, 406617/2023–6) and FAPERJ (E-26/211.186/2021, E-26/200.315/ 2023, E-26/204.445/2024)
The effect of different segmentation methods on the performance of prognostic models for early-stage non-small cell lung cancer
No full textLongkanker is wereldwijd de dodelijkste vorm van kanker. Voor een betere overleving is een vroege diagnose en nauwkeurige stadiëring essentieel. Radiomics, een methode om parameters uit medische beelden te halen, kan dit proces verbeteren door patronen te identificeren die voor het menselijk oog onzichtbaar zijn. Segmentatie bepaalt het geanalyseerde gebied, wat invloed kan hebben op de radiomic parameters. Deze masterproef onderzoekt of de keuze van de PET-segmentatiemethode de prestaties van prognostische modellen voor niet-kleincellige longkanker (NSCLC) beïnvloedt.
In totaal werden 121 patiënten met stadium I-IIIA NSCLC geselecteerd uit de NCT03736993-trial (ProLUNG-studie) en de NCT02024113-trial. PET/CT-beelden werden gesegmenteerd met drie methoden (SUV4, MV2 en een AI-gebaseerde methode LIONZ). Radiomic parameters werden geëxtraheerd uit alle segmentaties. Vooraf geselecteerde parameters werden gebruikt als input voor prognostische modellen gebaseerd op logistische regressie of random forest.
Modelprestaties werden vergeleken tussen de segmentatiemethoden en modellen met behulp van de area under the curve (AUC)-waarden van de receiver operating characteristic curves. Een Friedman test toonde geen statistisch significante verschillen tussen de verschillende segmentatiemethoden. Verder toonde het model met alleen TLG de hoogste globale betrouwbaarheid (AUC 0,76 ± 0,14), terwijl de meest optimale combinatie het model met TLG, SUVmax en DmaxBulk voor MV2-segmentatie is (AUC 0,77 ± 0,16)
De Toekomst door Kinderogen: Photovoice als Venster op de Klas van Morgen
No full textHet onderwijslandschap staat voor grote veranderingen onder invloed van maatschappelijke evoluties zoals digitalisering, diversiteit en duurzaamheid. Terwijl beleidsmakers en onderwijsteams werken aan toekomstgerichte leeromgevingen, wordt de stem van kinderen zelf hierin vaak over het hoofd gezien. Nochtans benadrukken het VN-Kinderrechtenverdrag en het participatiemodel van Lundy (2007) dat kinderen recht hebben op een betekenisvolle rol in beslissingen die hen aanbelangen. Deze masterproef onderzoekt hoe kinderen van 6 tot 12 jaar zich de klas en de rol van de leerkracht voorstellen in het jaar 2050. De literatuurstudie identificeert drie pijlers die kwaliteitsvol en toekomstgericht onderwijs mee vormgeven: kinderparticipatie, de kenmerken van leerkrachten en de fysieke leeromgeving.
Op basis van dit theoretisch kader wordt tijdens 'Dag van de wetenschap' op UHasselt een exploratief en kwalitatief onderzoek uitgevoerd via photovoice: een visuele, participatieve methode die kinderen toelaat hun ideeën over onderwijs vorm te geven aan de hand van tekeningen en toelichtende gesprekken. De gekozen aanpak geeft kinderen niet alleen een stem, maar ook invloed en zorgt voor inzichten die bijdragen aan het ontwerpen van een onderwijspraktijk waarin hun leefwereld en wensen centraal staan. De resultaten vormen een waardevolle bron voor beleidsmakers, schoolteams en ontwerpers die onderwijs willen bouwen mét, in plaats van vóór, kinderen
Team Role Dynamics in Collaborative Research Teams: A Key to Participatory School Development
No full textIn recent decades, schools have faced increasing pressure to meet external expectations for quality and outcomes, requiring school teams, especially when dealing with a (super)diverse student populations, to provide efficient and context-specific responses. Collaborative research emerges as an attractive approach, wherein teams systematically reflect on their educational practices and (should) take data-and evidence-informed action to enhance students' learning. Involving additional stakeholders, such as students and in-service teachers, is considered beneficial, also in preparing pre-service teachers for inclusive education albeit under certain conditions. The current study, therefore, seeks to investigate the complex dynamics and expectations among diverse actors within collaborative research teams engaged in school development processes. This single case study unfolded at the Brussels CityScope Lyceum, where a collaborative research intervention was launched during the 2022-2023 school year to strengthen the student-teacher relationships through the implementation of bimonthly student talks. This school development process involved a diverse team, including teachers, students, pre-service teachers, a school leader and a teacher educator. Individual concept map-mediated interviews, based on Mumford et al.'s (2008) theoretical framework on team roles for school development, were conducted with 13 members of the collaborative research team. These interviews explored participants' perceptions of role allocation and conceptualization within the team, as well as their views on how these roles contributed to breakthroughs in the school development process. The resulting dataset was subjected to a combined deductive and inductive analysis strategy. The results unveil a landscape of both overlapping and diverging perspectives regarding role allocation and conceptualization among the actors of the collaborative research team. Moreover, the analysis delineates four distinct categories of breakthroughs that propelled the school development process forward in this particular case, with the following roles proving crucial: (1) cooperators and communicators foster connected communication and interaction, (2) contributors and critics enhance the enriching diversity of perspectives, (3) the consul role contributes to supportive leadership, and (4) creators and contractors guide processes of co-creation. The findings suggest that although all team roles are fulfilled, actors' expectations towards each other are only partially met, indicating potential for growth in creating truly participatory, reciprocal spaces for collaborative research. Despite these divergences, roles critical to the transformative potential of the school development process are assumed by multiple actors, possibly contributing to the success of the collaborative research in this case. Points of Interest • Collaborative research serves as an approach for school development at CityScope Lyceum in Brussels, focusing on improving student-teacher relationships by setting up periodic student talks. • Apart from teachers, pre-service teachers and a teacher educator, students are active participants in this collaborative research. • Within the collaborative research team, various actors assume distinct roles that complement each other, including those roles that prove crucial to the transformative potential of the school development process. • Yet, there is notable divergence among the actors in their allocation and conceptualization of team roles, suggesting the need to improve alignment in this regard, as well as transparent and intentional role assignment in settings of collaborative research for school development.The author(s) received no financial support for the research, authorship, and/or publication of this articl