Publikationer från Uppsala Universitet
Not a member yet
127603 research outputs found
Sort by
Rotor resistance optimization for balance between stability and economic sustainability in an electrical machine for a CRAFT-wind turbine
No full textWith the growing demand for renewable energy, floating offshore wind turbines such as the CRAFT-model demonstrate significant potential. Offshore installations benefit from more stable wind profiles andgenerally higher wind speeds compared to onshore sites. This study investigates the influence of varying rotor resistance values on both dynamic performances, primarily system stability and economic implications in a secondary asynchronous machine. Simulations were conducted in MATLAB under wind speeds of 5, 8, and 10 m/s, revealing how rotor resistance affects the system under different conditions. The results show that higher rotor resistance improves stability, as electrical and mechanical torque curves remain more in phase. However, this comes at the cost of increased rotor losses, leading toreduced efficiency. For example, annual energy production decreased from 9.1% for a rotor resistance of 0.16 Ω to only 0.89% for 0.02 Ω. From a mechanical cost perspective, the influence of rotor resistance on the dimensioning and cost of therotor shaft was almost negligible. Similarly, the Cost Of Energy Comparison (COEC) remained nearly constant across resistance values and windspeed, indicating that rotor resistance has limited economic impact in this regard. Nonetheless, the overall COEC values obtained were very low, suggesting favorable cost margins for the studied configuration. It can be concluded that a lower rotor resistance is affecting the system through higher risk of instability but with lower energy losses and higher efficiency, while higher values increase stability but with the side effect of higher losses. Meaning for a real-world application, it will be a tradeoff between stability and energy losses. Potential for future work includes the development of a closed-loop control system using PID regulation for dynamic rotor resistance adjustment, as well as improved modelling of turbine dynamics and flow interactions. Furthermore, a more comprehensive economic model is suggested, incorporating additional system losses and components to enhance the realism of CAPEX, OPEX, and COEC estimations. These improvements would allow for a more accurate and practical evaluation of system performance and cost-efficiency
ESG disclosure patterns in Northern Europe : A cluster analysis of companies’ sustainability profiles
No full textThis thesis explores how sustainability disclosures vary among Northern European companies, despite operating under similar regulatory and societal pressures. By using a cluster analysis of ESG (Environmental, Social and Governance) Pillar Scores from 2023, we identified patterns in how companies disclose information related to environmental, social, and governance issues. The method grouped companies into three distinct clusters, each reflecting different characteristics. One cluster includes companies with high ESG pillar scores and strong financials, another shows moderate disclosures with mixed financial results, and the third consists of companies with weaker ESG scores and lower financial strength. To provide possible explanations for these differences, the study applies institutional, stakeholder, legitimacy, and strategic theories. This thesis contributes to the research on ESG reporting by profiling companies in Northern Europe, providing novel insights into disclosure practices in the region
Dolt samband under vattenytan : Synkroniseringens roll i mottagaren
No full textThis thesis presents the implementation and integration of a synchronization algorithm for a wireless underwater communication modem. The project connects to three previous theses and is divided into two main parts: translating an existing synchronization algorithm from MATLAB to C, to enable execution on a micro-controller, and integrating the microcontroller with previously developed modules into a complete receiver modem. The synchronization algorithm was deployed on an STM32-based micro-controller. The performance of the algorithm was evaluated through test-bench simulations. The simulations showed the algorithm to successfully synchronize incoming signals and estimate key parameters such as doppler shifts and communication channel length. Furthermore, the micro-controller that executed the synchronization algorithm was successfully integrated into the underwater communication modem receiver, since the completed system proved to reliably decode message frames. This was shown by performing physical experiments in both water tanks and open water environment. The results show that the system was able to decode messages down to an SNR of -20 dB with almost 100% success rate. However, challenges remain to decode messages with large doppler shifts, largely due to memory storage and computational capacity on the micro-controller. In summary, the results show that it is possible to achieve real-time underwater synchronization using small, power efficient units. This creates a good starting point for developing a low-power, battery-powered acoustic modem that can work well in complex underwater conditions
“Managing to Critique” : Counterfactualism in Resource Management Games for Social Commentary
No full textThe game industry is a rapidly growing market that has surpassed both the music and film industries in terms of size. However, cases of unjust treatment of its workers, such as sexual misconduct and racism in the workplace, massive firing waves, and crunch culture, are reported regularly. We argue that a resource management game, in which the player acts as the CEO of a game studio, can make a meaningful comment on these malpractices by utilising procedural rhetoric, a concept first introduced by Ian Bogost. The thesis game prototype, set in Victorian London, uses counterfactualism to make a connection between the working conditions of Victorian and Modern times. Counterfactualism describes a thought-experiment that reinvents certain historic events, and often imagines how history may have transpired had these not happened. Based on the Research Through Design framework, we carried out a semi-structured focus group interview with six Game Design students to gather their opinions on the game prototype’s gameplay and procedural rhetoric. Conducting a thematic analysis, we identified four themes: Playstyle, Player Autonomy, Game vs. Reality, and Uncertainty. The study results showed that the game had the desired effect on the participants, as they successfully recognised the critique towards the game industry’s treatment of its workers
Cultural Narratives and Gambling : Traditional Practices vs. Modern Practices in India The Coexistence of Regulatory Challenges and Cultural Norms
No full textGambling in India is deeply rooted in cultural heritage and religious narratives that date back to ancient scriptures like the Mahabharata and exists today during festivals and family gatherings in spite of modern regulatory attempts to eradicate it. This thesis tries to investigate how these traditions shape informal gambling practices, as they become a starting point for many to get introduced to gambling and how it complicates formal regulation. Using an academic study approach along with a supporting survey, the study first reviews historical, mythological, and legal academic studies on gambling in India. It then implements a culturally sensitive survey with 32 respondents to measure different aspects of gambling in the lives of people. Findings reveal that 68 % of respondents strongly agree that gambling is normalised during festivals, especially Diwali. 75 % of respondents report playing card games mainly for social bonding and fun rather than monetary gain. 66 % agree with gambling’s potential harms, including debt, family conflict, and co‑occurring with alcohol abuse. Many also expressed support for stricter but culturally balanced enforcement of the law. 84 % of respondents show concern for the rapid growth of digital gambling platforms as an extension of already persisting traditional practices. These results reflect a constant tension between cultural legitimacy and legal prohibition on gambling practices in India. The thesis gives a perspective that effective harm reduction of gambling practices must honour India’s long-existing cultural traditions by distinguishing low‑stakes, communal play from problematic betting while updating regulatory frameworks through targeted education campaigns, clearer state laws, and community‑engaged interventions. Such balanced reforms may help safeguard vulnerable populations without driving informal gambling underground and making it a bigger challenge but there is a strong need for further research on gambling in India and regulatory measures
Automating Content Moderation in Windy.app Using Large Language Models
No full textThe proliferation of user-generated content on platforms designed for social interaction, including Windy.app, poses significant challenges for manual content moderation, impacting scalability, consistency, and timely intervention. This thesis addresses the problem of enhancing content moderation efficiency and effectiveness by leveraging Large Language Models (LLMs). The research investigates the development of a structured moderation taxonomy, the selection of optimal LLMs based on performance and production readiness, and the design of an LLM-powered moderation pipeline incorporating essential human oversight. The study involved creating a bespoke six-category moderation taxonomy for Windy.app, operationalized through prompt engineering. A comprehensive empirical evaluation of fifteen LLMs was conducted, identifying Google's Gemini 2.0 Flash Lite as the most suitable due to its balance of accuracy, coverage, and operational viability. Based on these findings, a proof-of-concept (PoC) system called "WindyGuard" was designed and implemented. This system features a microservice architecture, asynchronous communication, and a Human-on-the-Loop workflow, enabling automated handling of straightforward content and human review for complex cases or appeals. The results demonstrate the feasibility of an LLM-based approach to significantly augment content moderation. The PoC system successfully implements the designed taxonomy and pipeline, showcasing a practical method for balancing automation with human judgment. The selected LLM performed effectively on a standardized benchmark, indicating its potential for real-world application. This thesis provides a framework and a functional prototype for Windy.app to develop a more scalable, consistent, and insightful content moderation system. The findings and the implemented PoC are useful for platforms seeking to integrate LLMs into their moderation processes while maintaining ethical considerations and human control over nuanced decisions, contributing to safer and more respectful online communities
Phonics i årskurs 1 : En granskning av lärarhandledningar med fokus på skriftspråkets form
No full textFraming the Digital Nomad Destination: An Analysis of Asia’s YouTube Representations and Pakistan’s Invisibility
No full textAI Teammates in Overwatch 2: Investigating Player Experience and Game Dynamics through Self-Determination Theory
No full textArtificial Intelligence (AI) has become an essential aid in making videogames. AI characters could have an impact on shaping players' experience, particularly in team-based multiplayer environments. In competitive environments, when players leave mid-match, it puts their team at a significant disadvantage, possibly disrupting balance and negatively impacting the overall gameplay experience. Valve’s earlier solution in Counter-Strike: Global Offensive (CS: GO), which employed semi-responsive AI to replace disconnected players, was discontinued in 2021. Since then, no viable alternatives have been introduced, leaving a critical gap in how games address team imbalance and player experience during incomplete matches. This study investigates how the integration of AI can be optimised to preserve or enhance the gaming experience for players, using Self-Determination Theory as a lens and Overwatch 2 as a case study. A mixed-methods user study was conducted using questionnaires, gameplay observation, and semi-structured focus groups. Findings revealed that AI teammates often undermine autonomy and competence due to rigid, context-unaware behaviours. Players reported communication breakdowns and a lack of strategic coordination, reducing their sense of agency and effectiveness. Trust, as a facet of relatedness, varied by context; players expressed more confidence in AI on attack than on defence. Players also reported diminished immersion, a key dimension of the lived experience explored through phenomenology. The findings reveal psychological and social tensions when AI replaces human players and suggest design implications for building more responsive, human-like AI teammates.