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Enhancing Sampling-Based Path Planning for Autonomous Robots in Confined Areas
No full textThis thesis investigates how different variants of the Rapidly-exploring Random Tree (RRT*) algorithm can be used to plan drivable paths for autonomous vehicles in confined environments. The focus is on comparing the standard version of RRT* with an improved version that uses informed sampling to make the search for the optimal path more efficient. Furthermore, the vehicle’s steering function is a major focus, the movement constraints of a real car, with the aim of generating physically drivable paths. The study was conducted in three different simulated environments: an alley, a warehouse space, and a U-turn, each representing different levels of complexity and constraints. The results show that the improved variant of RRT* led to noticeable improvements in some cases, especially in the open warehouse environment, where informed sampling effectively avoided unnecessary exploration. In simpler and more confined environments, such as the alley, the differences were small, as both algorithms produced similar solutions. Statistical analysis using the Fréchet distance and the number of nodes showed that informed sampling can reduce computational complexity and improve search outcomes in the right type of environment. However, the results are also influenced by the quality of the initial path — particularly in more complex scenarios like the U-turn. The conclusion is that informed RRT* has the potential to improve both the efficiency and robustness of path planning, but its benefits are highly dependent on the structure of the environment and the initial conditions
Therapeutic Alliance and Norm-Breaking Behavior in Work with Youth
No full textPsykisk ohälsa bland ungdomar har ökat, och många söker hjälp inom barn- ochungdomspsykiatrin. Forskning visar att den terapeutiska alliansen är viktig för hur brabehandlingen fungerar, särskilt i arbete med ungdomar med normbrytande beteende. Syftetmed denna studie var att undersöka hur behandlare upplever alliansens betydelse iförändringsarbetet. Tio behandlare intervjuades och materialet analyserades med tematiskanalys.Fyra teman identifierades: trygghet som grund för allians, alliansen som nyckel tillförändring, delaktighet i förändringsarbetet samt att reparera alliansen vid motstånd.Resultaten visar att en stark allians är avgörande för att skapa engagemang och möjlighettill förändring, särskilt när ungdomar har tidigare negativa erfarenheter. Studien kan bidramed ökad förståelse för vad som krävs av behandlare i arbete med denna målgrupp.
“Self-efficacy is my inner security” : A study on how junior real estate agents experience their work-related self-efficacy
No full textSyftet med denna studie var att utforska hur juniora fastighetsmäklare upplever sin arbetsrelaterade självförmåga samt vilken betydelse de upplever att den har för deras arbete. Studien genomfördes genom semistrukturerade intervjuer med tio fastighetsmäklare som har varit verksamma i mindre än fem år. Det insamlade materialet analyserades med induktiv tematisk analys. Resultatet visade att självförmåga upplevdes ha en tydlig roll i arbetet, särskilt i hur deltagarna tog initiativ, hanterade vardagliga utmaningar, resonerade kring beslut och bevarade motivation. Självförmågan beskrevs både utifrån personliga erfarenheter och konkreta uttryck i arbetets praktiska delar, och kunde vara förknippad med såväl trygghet som inre osäkerhet. Resultaten diskuterades i relation till tidigare forskning och teoretiska perspektiv på självförmåga
Dimensionering av fläktsystem till ett kraftvärmeverks rökgaskondensering
No full textCombined heat and power (CHP) plants play a central role in Sweden’s energy transition by producing both electricity and heat from renewable sources, thereby helping to reduce the use of fossil fuels and greenhouse gas emissions. This study focuses on the flue gas condensation system at the Johannes biomass CHP plant in Gävle, where operational issues have arisen due to system upgrades that were not fully matched by adjustments to all subsystems. By adapting the flue gas fan to actual operating conditions, the capacity of the condensation process can be optimized, enabling more energy-efficient operation and reduced operational costs.The purpose of this work is to increase the performance of the flue gas condensation system in order to ensure cost-effective and environmentally sustainable heat production. The goal is to provide a decision-making basis that supports increased condensation capacity from a cost-efficiency perspective. A comprehensive system analysis was carried out using flow diagrams, measurement instruments, and staff input to create a complete picture of the system’s operation. Data were collected from Gävle Energi’s monitoring system during the winter months, allowing for performance analysis under high load conditions. Particular focus was placed on the performance of the flue gas fan, where differential pressure and rotational speed were analyzed against the manufacturer’s specifications. It was found that the fan does not reach its specified capacity, causing the bypass valve to open and thereby reducing condenser efficiency.Operational data show that the existing flue gas fan is underutilized, despite its capability to handle higher mechanical loads at increased rotational speed. By raising the motor frequency to 60 Hz, the fan’s capacity can be increased by 9 percent. The highest measured volumetric flow was 257 000 m³/h, which significantly exceeds the current capacity. To meet demand 99 percent of the time, a flow rate of 232 000 m³/h is required. According to the manufacturer’s data, this can be achieved by equipping the fan with a larger motor.Increasing the fan speed to 1200 rpm by adjusting the frequency has been identified as a viable solution to increase flow rate. However, this would require further investigation into the motor’s mechanical integrity, as well as checks on alignment and bearing load. The study also shows a correlation between increased flow, higher power consumption, and reduced pressure, which should be further evaluated from an energy efficiency perspective. Since the purpose of the flue gas condensation system is to conserve energy and reduce environmental impact, it is essential to ensure that the system operates efficiently and without unnecessary losses
Automatiserad batterisortering med datorseende och djupinlärning : Python-baserat system för objektigenkänning och sortering med visionsystem och robot
No full textThe recycling industry faces the challenge of rapidly and accurately sorting large volumes of cylindrical batteries. This study presents an AI-based vision system that integrates a GPU-accelerated YOLOv5 model for real-time detection of buttoncells and cylindrical batteries with a UR3 robot for automated picking. Affine transformations map image coordinates to the robot’s workspace, and an asynchronous queue architecture ensures continuous processing without unnecessary stops. The system achieved 98 \% precision and 96 \% recall, with [email protected] of 97 \% and [email protected]:0.95 of 81 \%, while maintaining inference times around 20 ms per frame. The average pick cycle time was 5.48 s with continously running conveyer belt and detection stability remained above 95 \% at conveyor speeds up to 345 mm/s and when handling tightly clustered objects at speeds up to 200 mm/s. These results demonstrate that coupling AI vision with collaborative robotics can deliver both high accuracy and throughput. The system’s modular architecture allows straightforward scaling to additional battery types and higher processing rates, highlighting its potential to improve efficiency, precision, and sustainability in recycling
Construction Firms’ Capacity for Environmental Sustainability Transition : How Company Size Shapes Opportunities for Environmental Sustainability
No full textByggsektorns övergång till miljömässig hållbarhet kräver att företag effektivt identifierar, utnyttjar och omstrukturerar till nya lösningar. Syftet med denna studie är att fördjupa förståelsen för vilka hinder och drivkrafter byggföretag i olika storlek möter i sitt omställningsarbete, samt hur organisatoriska och resursmässiga faktorer påverkar omställningsförmågan. Studien bygger på nio semi-strukturerade intervjuer med fem små- och medelstora företag (SME, 40–230 anställda), tre större företag (≥ 400 anställda) och en privat beställarorganisation. Intervjuerna kombinerades med en riktad litteraturstudie och de analyserades abduktivt med ramverket Dynamic Capabilities (sensing–seizing–reconfiguring) som analytisk lins. Resultaten visar att samtliga företag klimatberäknar sin verksamhet, men resurstillgång, beslutshastighet och formella processer skiljer sig markant mellan storleksgrupper. SME har begränsad kapacitet för systematisk omvärldsbevakning men kan snabbt justera arbetsmetoder när beställarkrav eller lagkrav ändras. Stora företag har dedikerade hållbarhetsteam och bättre finansieringsmöjligheter, men drabbas av organisatorisk tröghet som fördröjer implementeringen av nya lösningar. Företag med uttalad förbättringskultur och tydliga interna ramverk uppvisar högre omställningsförmåga, oberoende av storlek. Slutsatsen är att företagsstorlek i sig inte avgör framgången i hållbarhetsomställningen. I stället är välutvecklade dynamiska förmågor, ledningens engagemang och transparent styrning de mest avgörande faktorerna. För att påskynda omställningen rekommenderas lagstiftare och beställare att införa skärpta utsläppsgränser, standardiserad koldioxid budgetering och ekonomiska incitament som kompenserar initiala investeringskostnader.The construction sector’s transition to environmental sustainability demands that firms effectively identify, exploit, and reconfigure toward new solutions. This study aims to deepen the understanding of the barriers and drivers construction companies of different sizes face in their transition efforts, and to examine how organizational and resource factors shape their transformation capability. The research is based on nine semi-structured interviews with five small- and medium-sized enterprises (SMEs, 40–230 employees), three large firms (≥ 400 employees), and one private client. Interview data were complemented by a targeted literature review and analyzed abductively through the Dynamic Capabilities framework (sensing–seizing–reconfiguring). Findings show that all companies calculate the climate impact of their operations, yet resource availability, decision speed, and the formality of processes differ markedly between size groups. SMEs have limited capacity for systematic environmental scanning but can rapidly adjust working methods when client or regulatory requirements change. Large firms benefit from dedicated sustainability teams and stronger financing options, but organizational inertia slows the implementation of new solutions. Companies that foster a strong culture of continuous improvement and maintain clear internal frameworks exhibit higher adaptive capacity, regardless of size. The study concludes that firm size alone does not determine success in the sustainability transition. Rather, well-developed dynamic capabilities, engaged leadership, and transparent governance are decisive. To accelerate progress, legislators and clients are encouraged to introduce tighter emission thresholds, standardized carbon budgeting, and financial incentives that help offset upfront investment costs.
Exploring the Potential of Pyridine Carboxylic Acid Isomers to Discover New Enzyme Inhibitors
No full textPyridine carboxylic acid isomers - picolinic acid, nicotinic acid, and isonicotinic acid - have historically resulted in a plethora of drugs against tuberculosis, cancer, diabetes, Alzheimer's, angina, dementia, depression, allergy, respiratory acidosis, psoriasis, acne, hypertension, hyperlipidemia, HIV/AIDS (specifically HIV-1), among others. Despite the large number of therapeutic agents derived from these isomers, the research involving these scaffolds is still exceptionally active. The current surge in enzyme inhibitory activities by the compounds derived from them has further created space for the discovery of new drug candidates. This review focuses on the medicinal relevance of these isomers by analyzing structure-activity relationships (SARs) and highlighting emerging trends from patents filed over the last decade. Notably, pharmaceutical giants like Bayer, Bristol-Myers Squibb, Novartis, Curis, and Aurigene have developed enzyme inhibitors based on these scaffolds with nanomolar potency. The role of these isomers in the development of antiviral agents, including protease inhibitors, is also discussed. Overall, this review brings to the readers, a pragmatic opportunity to comprehend the recent literature, highlighting the scaffolds' importance in the design of new enzyme inhibitors. Furthermore, it discusses the structure-activity relationship of pyridine carboxylic acid-derived compounds and highlights the current patenting trends in medicinal chemistry
Korrosionsrelaterade problem i armerade betongkonstruktioner, förebyggande arbeten och åtgärder
No full textCorrosion-related damage is currently the leading factor in reinforced concrete structures experiencing reduced strength values. By finding sustainable methods to counteract corrosion-related problems in buildings, as well as alternatives to strengthen structures where corrosion has already occurred, the construction industry can develop where sustainability is the focus. This study is therefore being conducted out of interest in sustainability within the construction industry where future buildings are desired to be constructed with durability, cost-effectiveness and lifespan in mind. The study has compiled significant information linked to the stated questions from 38 previously published scientific articles and research materials. The study has also obtained information regarding the implementation of these proposals in practice from interviews with people in the construction industry. Since previous research regarding corrosion problems in reinforced concrete structures is relatively extensive, this has a positive impact on this study as relevant information will be available from a broad database. The results of the study show that a decisive factor in the design of reinforced concrete structures is the accuracy of the preparatory work, as well as regular checks of the structure after construction. Information from the literature study linked to which methods of strengthening reinforced concrete structures with corrosion-related problems, as well as the preventive measures, show clear suggestions for alternative approaches to minimize the risk of corrosion in the structure. Based on the literature study, several methods of strengthening and preventive measures are compared, where the results show clear improvements in corrosion resistance and strength. Previous studies where fiber-reinforced polymers have been used to strengthen concrete beams have shown an improved load-bearing capacity of 75.88%. This can be a decisive factor in the occurrence of corrosion-related damage as the concrete cover layer does not risk the same degree of unwanted cracks. Studies on microbial repair agents where Bacillus subtilis is the active component have also shown favorable results in crack repair work. Through a comparative study where control groups with different amounts of Bacillus subtilis were mixed into the microbial repair agent, a clear change can be seen linked to the flexural stiffness of the concrete sample. Despite differences in cross-sectional area and concrete quality, the results from the different studies where microbial repair agents have been used to enhance the flexural stiffness of the concrete samples show similar responses. From tests where different amounts of Bacillus subtilis have been implemented in the mixture, previous research shows that a 0.1% concentration has the greatest positive impact on flexural stiffness. The difference between the concrete sample with 0.0% concentration and the one with 0.1% shows an increase in flexural stiffness as high as 4.55%. This increase is considered to be crucial for the lifespan of the structure as cracking that can cause corrosion does not occur to the same extent. Based on the results of the survey where several methods for maintenance, strengthening, and repair of damaged concrete structures are highlighted, a clear comparison can be made between the methods. Since methods for strengthening and repairing these types of damages are often directly tailored to the shape of the structure, the extent of the damages, and the geographical location of the building, it can be practically challenging to determine which of the methods is best suited for the specific work. This has led to a general method often being used in practice, where the damages are addressed in a similar way regardless of the previously mentioned factors
Migrating to the Cloud: Success Factors When Moving from Legacy Systems to AWS
No full textCloud migration of legacy IT systems has become a central part of many organizations' digital transformation strategies. Although the cloud offers scalability, flexibility, and cost-efficiency, the migration process involves both technical and organizational challenges. The purpose of this study was to investigate the factors that contribute to a successful migration of legacy systems to the AWS cloud platform, with a particular focus on the interplay between technology, organization, and leadership. The study was based on a qualitative case study of the company Playground Tech and their cloud migration efforts following the AWS Migration Acceleration Program (MAP). Through semi-structured interviews and document analysis, key success factors were identified, such as a thoroughly executed discovery phase, strategic use of Rehost as the initial migration approach, and clear role allocation combined with focused leadership (single-threaded leadership). The results showed that a successful migration is not an isolated technical task, but rather a complex change process that requires organizational maturity, effective communication, and continuous skill development. The study confirmed previous theoretical frameworks within the field but also contributes practical insights into how established models are applied in real-world scenarios. Finally, the study discussed its limitations and potential directions for future research, such as the need for long-term follow-up and comparisons between different cloud platforms
Division as Diversion? : A Quantitative Study on Domestic Causes of Russian Disinformation
No full textThe rise of state-sponsored disinformation targeting foreign countries has become an increasing concern in contemporary security policy, in which Russia is deemed to be one of the most influential practitioners. This calls for further research on its strategies, specifically which countries are targeted and when. The aim of this thesis is therefore to explain what causes increased disinformation frequency by studying its correlation with domestic unrest in Russia and in target countries. Both of these potential drivers of disinformation are identified based on previous research conducted on Russian disinformation and diversionary war theory. Data on disinformation frequency is coded from the database of EUvsDisinfo, where assessed Russian disinformation articles are published. Such articles are collected for 18 countries with former relations to the Soviet Union and further compared, across countries and over time, in an OLS regression. The results find partial support for the diversionary theory in this new context, in which Russian protests decrease foreign deployed disinformation while riots increase it. Stronger support is found for protests and riots in target countries affecting disinformation frequency, reinforcing the concept of active measures in Russian disinformation strategy. Violent demonstrations carry a stronger effect than peaceful ones. However, the estimates related to elections are not statistically significant. These findings contribute to the knowledge on Russian disinformation strategy, which is of importance in building resilience against influence operations