Publikationer från Uppsala Universitet
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ESG och kapitalstruktur : En kvantitativ studie på svenska företag
No full textStudien syftar till att undersöka sambandet mellan ESG och kapitalstruktur i svenska företag. Detta är relevant eftersom nya regleringar har ökat kraven på företag att rapportera ESG-information. För att undersöka detta kombineras teoretisk ram och multipel linjär regression med paneldata. De teorier som används är trade-off-teorin, pecking order-teorin och signalteorin. Måttet på ESG är ESG-betyg och kapitalstruktur mäts med skuldsättningsgrad. En POLS-modell skattas för att undersöka det generella sambandet och en tvåvägs-modell med fasta effekter i robusthetssyfte. POLS-modellen indikerar ett negativt signifikant samband, där högre ESG-betyg har ett samband med en lägre skuldsättningsgrad. Tvåvägsmodellen hittar inte något signifikant samband mellan ESG-betyg och skuldsättningsgrad. Detta tolkas som att sambandet är mellan företag snarare än förändringar över tid inom företag. Resultaten avvek från vad klassiska kapitalstrukturteorier förutspår, vilket tyder på att ESG inte har blivit integrerat i teorierna. En utveckling av signalteorin formulerades, där ESG och kapitalstruktur potentiellt kan fungera som risksubstitut. Detta skulle även kunna förklara det motstridiga resultatet i trade-off-teorin.
AI som kollega eller konkurrent? : - En kvalitativ studie om generativ AI i revision
No full textAllt större investeringar görs inom generativ AI för revisionsbyråer, däremot finns flera utmaningar för implementeringen. Problemen uppstår med högre krav på etisk användning och hanteringen av desinformation. Tidigare forskning tyder på förbättrat beslutsfattande, samtidigt finns begränsade studier om generativ AI:s påverkan på beslutsfattande inom revision. Denna studie ämnar att undersöka hur implementeringen av generativ AI påverkar beslutsfattande för revisorer i Sverige. I studien har en kvalitativ metod tillämpats där data har samlats in genom semistrukturerade intervjuer med revisorer från små, medelstora och stora revisionsbyråer. Resultaten indikerar att generativ AI används som ett beslutsstöd snarare än att automatisera beslut. Faktorer som påverkar hur generativ AI används för beslutsfattande är kognitiva begränsningar, informationskvalitet, etiska aspekter och relationen mellan automation och augmentation i revisionsbyråer. Dessa faktorer bör beaktas för utvecklingen av branschen. Studien drar slutsatsen att augmentation är optimalt för beslutsfattande och automatisering för enklare uppgifter
Kontaktsjuksköterskors erfarenhet av att bedöma och hantera immunterapirelaterade biverkningar inom cancervården
No full textBakgrund: Immunterapi har blivit en grundpelare inom cancerbehandling och dess biverkningar skiljer sig från andra terapiformer och kan både vara svårtolkade och debutera sent i behandlingsförloppet. Detta ställer krav på sjukvårdens förmåga till tidig upptäckt och korrekt bedömning. Kontaktsjuksköterskor har ofta en central roll i att identifiera dessa biverkningar, vilket motiverar behovet av att undersöka deras erfarenheter. Syfte: Att beskriva kontaktsjuksköterskors erfarenheter av att bedöma och hantera immunterapirelaterade biverkningar inom onkologi. Metod: Kvalitativ studie med semistrukturerade intervjuer och kvalitativ innehållsanalys. Sju kontaktsjuksköterskor från universitets- och regionsjukhus med minst ett års erfarenhet av immunterapi deltog. Resultat: Kontaktsjuksköterskorna upplevde bedömningen av biverkningar från immunterapi som komplex. Vissa biverkningar var lättare att identifiera än andra, och det fanns en risk för både under- och överskattning av allvarlighetsgrad. Telefonbedömning, patienters underrapportering, samsjuklighet och kombinationsbehandling försvårade bedömningen, medan stödverktyg underlättade processen. Att hitta en balans vid informationsgivning om behandlingen, skapa tillit och vara tillgänglig samt vikten av kollegialt och tvärprofessionellt samarbete lyftes fram som viktigt vid hantering av biverkningar. Utbildning inom immunterapi upplevdes otillräcklig, samtidigt som yrkeserfarenhet ansågs vara avgörande för säker och korrekt bedömning. Slutsats: Bedömning och hantering av immunterapibiverkningar är komplext och kräver omfattande kunskap och hög klinisk kompetens. Kontaktsjuksköterskan har nära kontakt med patienten och är viktig för tidig identifiering, rätt åtgärder och patientens möjlighet att fullfölja behandlingen med bibehållen livskvalitet. Background: Immunotherapy has become a cornerstone of cancer treatment, and its side effects differ from those of other therapies — they can be difficult to interpret and may appear late in the course of treatment. This places demands on healthcare's ability to detect and assess these effects early. Contact nurses often have a central role in identifying such side effects, which motivates the need to explore their experiences. Aim: To describe contact nurses' experiences of assessing and managing immunotherapy-related side effects in oncology. Method: Qualitative study using semi-structured interviews and qualitative content analysis. Seven contact nurses from university and regional hospitals with at least one year of experience in immunotherapy participated. Results: Contact nurses perceived the assessment of side effects from immunotherapy as complex. Some side effects were easier to identify than others, and there was a risk of both underestimation and overestimation of severity. Telephone assessments, patient underreporting, comorbidity, and combination treatments complicated the assessment, while support tools facilitated the process. Finding a balance in providing information about the treatment, building trust and being accessible, as well as the importance of collegial and interprofessional collaboration, were highlighted as important in managing side effects. Education in immunotherapy was perceived as insufficient, while clinical experience was considered crucial for safe and accurate assessment. Conclusion: Assessment and management of immunotherapy-related side effects is complex and requires extensive knowledge and high clinical competence. The contact nurse has close contact with the patient and plays a key role in early identification, appropriate interventions, and enabling the patient to continue treatment while maintaining quality of life.
A doll in a dollhouse : A cultural historical study of beauty ideals and gender orders from material culture 1700–1850
No full textThis paper is a cultural historical study that examines dolls and dollhouses during the period 1700 to 1850 in relation to social and cultural aspects. The aim is to examine how ideals of beauty and gender order sre reflected in the aesthetics and design of the objects, and how this has changed over time. The study alos aims to promote material culture and object research in relation to cultural historical studies and gender studies. The source material comes from the Nordic Museum in Stockholm and consists of four fashion dolls (two from the 18th century, two from the 19th century) and two dollhouses (dated ca. 1680–1740 and 1800)
Symbolic Regression to Analyse Toeplitz matrices : Unearthing Spectral Truths with Symbolic Regression
No full textSymbolic regression (SR) is a regression method that searches for a mathematical expression that fits a data input. In this project, SR will be used to find the spectral symbols of Toeplitz matrices. Toeplitz matrices, named after Otto Toeplitz, are matrices that have constant diagonals from left to right. Toeplitz are important for reasons that will be explained, but for now all you need to know is that Toeplitz matrices are associated with so-called symbols, the generating symbol and the spectral symbol. The generating symbol is a function that is connected to the entries of the matrix. The spectral symbol is a function that is affiliated with spectrum of the matrix, in the case of Hermitian matrices, these symbols are the same. The main goal of this project is to determine the usefulness of SR as tool to determine these spectral symbols. In this project, both known and unknown spectral symbols are studied. The results are mixed, all known symbols were successfully replicated, meanwhile, none of the unknown symbols were able to be inferred. This leaves one questioning,if SR will find these unknown symbols or if it is impossible. But in either case only further studies can reveal the true answer
Climate-improved concrete : Considerations in project design and execution
No full text This thesis investigates climate-improved concrete from technical and environmental perspectives, focusing on how alternative binders affect material properties and practical application. The aim is to increase understanding of performance, climate impact, and feasibility within the construction sector.The study combines a literature review, qualitative interviews with 13 industry professionals, and quantitative climate impact calculations. These calculations cover various cement types, exposure classes, and water-cement ratios, using both conventional and recycled reinforcement.Results show that concrete made with lower clinker cement types, such as CEM II/B, combined with recycled reinforcement, can reduce climate impact by up to 50%, with the lowest measured value being 40.1 kg CO₂/m³. However, this comes with technical challenges, including slower strength development, greater early frost sensitivity, and increased risk of plastic shrinkage cracking, particularly without proper curing. Advantages include lower heat development and, in some cases, improved chemical resistance.Stakeholder attitudes vary, with skepticism often stemming from knowledge gaps rather than proven limitations. The study highlights the need for enhanced competence, clearer guidelines, and continued innovation. The upcoming SS-EN 1992-1-1:2023 standard is expected to support implementation through updated structural requirements.In conclusion, climate-improved concrete is a viable and sustainable alternative when applied with expertise, requiring industry collaboration and further development to realize its full potential
Safe Adaptive Control Using Differential Inclusions and Nonlinear Model Predictive Control
No full textControlling nonlinear systems with unknown dynamics is a major challenge, especially when safety and re liability are important. This thesis presents a robust Model Predictive Control (MPC) approach that uses differential inclusions to handle uncertainty in system behavior. The unknown dynamics are approximated using interval bounds based on finite-length trajectory data, allowing the controller to make safe decisions without requiring a complete model. The MPC is designed to work with these bounds, formulated with CasADi and solved using IPOPT framework to ensure constraint satisfaction and stability despite model uncertainties. The method is validated through simulations on three systems: a unicycle model for trajec tory tracking, an unmanned aerial vehicle (UAV) performing obstacle avoidance, and a two-link manipulator required to reach a reference point. The results demonstrate that the approximation algorithm provides con servative but reliable bounds, even with small data sets being stored, enabling the robust MPC to navigate uncertain environments safely and achieve tracking objectives. However, a key limitation of the proposed approach is the computational cost of solving the robust MPC problem online, particularly as the complex ity of the system increases. Moreover, stability guarantees cannot be provided in general for systems with unknown or highly uncertain dynamics, especially when only limited data are available for model learning or uncertainty quantification. Formal stability guarantees are difficult to establish in these settings. As such, the method should be viewed as a safety-oriented control strategy with adaptive capabilities, rather than a universally stabilizing solution. However, the framework demonstrates potential to achieve safe control in constrained scenarios and lays the foundation for future improvements in computational efficiency and theoretical guarantees
Estimating the neutron yield in a deuterium-tritium plasma with the JET neutron camera
No full textThe JET neutron camera is used to monitor a 2D profile of the neutron emission from the plasma, using 19 sightlines with plastic scintillators suited for measuring neutrons from the D + T → n + 4He (DT) reaction. This paper describes an independent, first-principles physics method for estimating the volume integrated DT neutron yield with the neutron camera. This is performed for a selection of shots from the two recent DT campaigns at JET, the DTE2 and DTE3 JET campaigns. It covers the data reduction methods from a light yield calibration of the scintillators to treatment of pile-up, which is prevalent during high yield DT experiments. Several models of the camera geometry are used to account for scattering and transmission effects in the neutron transport. The neutron yield is estimated using models of the neutron emission profile, which are fitted to measurement data. The neutron yield estimates from this method are compared to corresponding estimates from the JET fission chambers. Our estimates with the neutron camera are on average 34% and 41% higher than the fission chamber estimates for DTE2 and DTE3, respectively. The reasons for the discrepancies between the two systems are presently unknown and prompt further investigation. In this paper, we detail the methods used to reach the neutron yield estimate from the neutron camera, along with their strengths, weaknesses, and potential points of failure. This method is an evolution of an earlier work that estimated the deuterium–deuterium neutron yield using similar methods
Modellering och styrsystemdesign för europeisk balansering av havsbaserad vindkraft och HVDC-förbindelser
No full textThis thesis investigates how offshore wind farms connected via high-voltage direct current (HVDC) links can support frequency balancing between two synchronous areas in Europe. A simulation model was developed in MATLAB/Simulink to evaluate four control strategies for managing power imbalances caused by wind forecast errors. The strategies include routing the imbalance to one area, sharing it between both, or managing it locally at the wind farm with a simplified battery model. The model incorporates HVDC constraints, reserve limitations, and optional filtering of the imbalance signal. Simulations using real wind data show that sharing the imbalance between areas results in the most optimal balancing control strategy. Routing all imbalances to a single area often causes HVDC saturation, ramping limitations, or insufficient frequency reserve. While local battery control can smooth short-term imbalances, it is not scalable for longer durations. The results highlight the importance of frequency reserve availability and HVDC transmission headroom for maintaining system stability, especially as offshore wind integration expands through more complex and interconnected grid systems.
