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  • Bäckström, Simon
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Ståhl, Matilda
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Resurseffektivisering i rymdindustrin: En jämförande studie av Lean- och Agila produktionsstrategier hos storskaliga och småskaliga rymdaktörer2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The space industry is currently undergoing a major transformation, with private companies emerging as key players. What was once a state-dominated field is now opening for smaller, Agile firms to establish themselves in this tech and capital-intensive sector. Two production strategies that are frequently used today, and are successfully used in other high-tech industries, are Lean- and Agile manufacturing. This study investigates how a combination of these methods, a LeAgile production, can be used by smaller actors to challenge established players in the space sector.

    NASA and SpaceX represent two well-established actors that have shaped the modern space industry in different ways. NASA, a publicly funded, non-profit organization, is characterized by a slower, more bureaucratic approach. In contrast, SpaceX exemplifies a commercially driven company where innovation and rapid development are key drivers. Pythom Space represents a third category, as a small private company seeking to carve out a space in the industry. Through a comparative analysis of how these three actors apply Lean- and Agile production strategies, the study explores how such methods can increase revenue, improve flexibility, and shorten project lead times.

    The results show that NASA’s traditional model often results in long lead times and high development costs. Projects are characterized by bespoke solutions, heavy documentation and limited standardization, making it difficult to apply Lean or Agile methods. In contrast, SpaceX has successfully integrated both principles. Through reusable components, vertical integration, rapid iteration and customer-oriented solutions, the company has dramatically reduced project timelines and costs while scaling its operations to meet commercial demand.

    Pythom Space demonstrates how Agile methods, such as short iterations, digital twins and modularity, combined with Lean-inspired practices like low capital intensity and decentralized manufacturing can create an efficient, flexible and resource-efficient organization. By developing its own mission profile focused on small, easily assembled rockets with low launch cost, Pythom has positioned themselves in a niche market segment. This Agile approach enables quick adaption, late-stage customer involvement and technological innovation.

    Eventually, the study shows that the choice of production strategy is crucial for a successful entry into the space industry. Lean and Agile methods not only enhance efficiency but also enable innovation and adaptability in a sector marked by rapid technological progress. For smaller actors like Pythom Space, this offers a valuable market opportunity to enter the market, both as independent players and as partners to larger organizations. However, the analysis also reveals that production strategy alone is not enough to ensure long-term competitiveness. To scale operations and meet the expectations of customers, investors and regulators, a stable organizational structure is required. With clear processes for quality assurance, capital acquisition, talent development and continuous learning within the organisation, small actors can become a real player.

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  • Lindström, Valter
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Fant, Frida
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Från diesel till el: Strategier för framtidens lastbilsproduktion2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The ongoing electrification of heavy trucks represents a profound transformation for the commercial vehicle industry, affecting not only the driveline but also the structure and logic of the entire production system. This thesis examines how production strategies are developed and adapted in response to electrification, with a particular focus on the role of modularization, flexibility, resource efficiency, scalability, and digitalization. The study applies a comparative case study of Volvo and Scania, combining a literature review with qualitative interviews to explore how these firms navigate the transition from diesel to electric drivetrains. The analysis highlights differences in strategic orientation, investment decisions, and supply chain integration. While Volvo emphasizes integration into existing structures to enable a fast market entry, Scania pursues a more modular, long-term approach based on system flexibility. The findings show that successful production systems for electric trucks require not only technical solutions but also organizational adaptability, digital capability, and the ability to manage uncertainty in both demand and technology development. The thesis concludes that modularity and scalability, supported by digital infrastructures, are key to building robust and future-proof manufacturing systems for the electrified transport sector.

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  • Arevång Højsgaard, Oscar
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Blomberg, Angelica
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Eggprepareringens påverkan i industriell produktion: Eggradie och verktygslivslängd hos omskärpta borrar på Scania2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study investigated how edge preparation through drag finishing affected the tool life of re-sharpened drills used in industrial production at Scania Engine Manufacturing. Within Scania DM's current re-sharpening and edge preparation process, a need was identified for quality control after the drag finishing operation. The purpose of the report was to analyse the relationship between edge radius and tool wear, and to evaluate the organizational and technical requirements for implementing microscope as measurement equipment.

    The work was a combination of literature review, interviews, and experimental drill tests. Tests were performed on drills with varying processing times in a drag finish machine, and the edge radius were measured with a microscope. Flank wear and spindle torque was used as an indicator of tool life.

    The drilling tests showed that larger edge radius tended to result in greater flank wear and higher torque, indicating increased tool wear. The unprepared drill initially exhibited the lowest torque, but it increased toward the end of the test, suggesting a shorter tool life than the drills with moderate edge radius. The drills with moderate edge radius showed more stable torque curves, indicating a longer tool life. However, the results are limited by a small number of data points and measurement uncertainties.

    The interviews showed that a microscope can be integrated into the existing production environment, but the implementation requires clear instructions, training, and customized fixtures. The ability to systematically measure edge radii and wear was considered to contribute to better tool control, improved sustainability, and reduced resource consumption.

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  • Westerberg, Olof
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Lidberg, Gabriel
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Hybridproduktion och dess möjligheter med additiv tillverkning av metall i ett tillverkande företag2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study explores the potential implementation of metal additive manufacturing (AM) techniques, specifically Laser Powder Bed Fusion (LPBF) and Laser Metal Deposition (LMD), at Formec AB, a company specialized in CNC machining of injection molding tools. The aim is to analyze how these AM techniques could enhance resource efficiency by reducing material waste, shortening production lead times, and increasing manufacturing flexibility. Through a qualitative case study, Formec AB’s current production processes were mapped and evaluated against the introduction of a hybrid manufacturing strategy, combining AM technologies with existing CNC machining.

    The analysis clearly indicates that adopting such a hybrid approach could significantly reduce annual material waste by up to 100 tons of aluminum and cut the lead times for tool production by approximately half. Additionally, AM enables the manufacturing of complex and optimized geometries not achievable with traditional methods. However, the findings also highlight substantial barriers, including high initial investment costs and the specialized handling required for metal powders and shielding gases, posing notable economic and organizational challenges for Formec AB at present.

    Thus, the results underscore that while AM implementation at Formec AB holds considerable long-term potential, further economic analysis and technological maturation are necessary before recommending full-scale integration. This study provides an essential foundation for future strategic decisions regarding investments in additive manufacturing technologies among small and medium-sized enterprises in the manufacturing industry.

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  • Wallmark, Einar
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Teknologiska investeringar för ökat värdeskapande: Optimering av trävaruförädlingsindustrins produktionssystem2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    While the pulp and paper industry currently has a high degree of digitalization and automation and is undergoing a transformation toward smart manufacturing, it can be noted that the wood processing industry is lagging behind, this is evident in the form of an unintegrated factory environment and a relatively low utilization of digitalization and automation technologies in the production process. Swedish wood processing companies are currently facing a growing need to optimize their production systems to increase efficiency and flexibility, in order to remain competitive against manufacturing in low-wage countries, but also to strengthen financial value creation. The purpose of this study is to examine how wood processing companies within the forest industry can apply smart manufacturing technologies in their production systems to strengthen operational efficiency and financial value creation. Based on the study's purpose, a main research question has been formulated: "How can wood processing companies within the forest industry apply smart manufacturing technologies in their production systems to strengthen operational efficiency and financial value creation?". The study is primarily limited to wood processing companies within the Swedish forest industry, and only technologies directly connected to the internal production system are addressed. The methodology used to answer the study's research question includes a literature review and a case study, in the form of a site visit and an interview with a medium-sized Swedish wood processing company.

    The results showed a number of identified areas for improvement along with the application of smart manufacturing technologies. In the initial timber measurement phase, the application of big data environments and advanced data analytics can enable the incoming raw material to not only be registered but also have its properties analyzed in real-time. Furthermore, the implementation of the Industrial Internet of Things (IIoT) can create conditions for transferring this data between production resources in subsequent stages as well as with the enterprise system in real-time, enabling predictability from the very first step in production. Moreover, collaborative robots can be used to reduce personnel dependency and minimize setup times in the turning and sawing lines, packaging, and quality control. Through cyber-physical production systems, combined with advanced data analytics and big data environments, the settings of these processing machines can also be linked to incoming data from the timber measurement and scanning, creating a self-adaptive production system with higher precision. IIoT, cyber-physical production systems, and further system integration is concluded to have the greatest potential to synchronize and make the production flow and coordination between the different parts of the production system more effective. In addition, internal autonomous transport systems and external connected systems with raw material handling suppliers are relevant to create a more integrated and responsive production flow.

    The conclusion is that the implementation of smart manufacturing technologies has the potential to lead to significant financial value creation through improved financial key figures, more reliable production steps, and increased flexibility for the wood processing industry, provided that the implementation is carried out gradually in line with the company's conditions.

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  • Biström, Kalle
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Framtidens cementproduktion: Teknologiska lösningar för låg-CO2 cement & effektiv energiomställning2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The following work examines how the cement industry, which is one of the largest sources of global carbon dioxide emissions, can be transformed to become climate neutral. The aim is to provide an overall picture of where the emissions from cement production come from, and how different technological solutions can minimize this. Furthermore, the work examines what the industry and its supply chain look like today, to determine how the implementation of these technological solutions can be done.

    Through a literature study and an interview with Mikael Nordlander from Vattenfall, technological solutions and economic instruments to reduce emissions arising from cement production are analyzed. The technological solutions highlighted in the work are alternative binders, carbon capture, and electrification of the combustion process. The work shows that the technology for climate-neutral cement already exists to some extent, but that the transition requires coordination between technical solutions, industrial strategies, market structure and policy instruments. Financial incentives that can enable the transition have also been identified. Margin contracts, double-sided auctions and green bonds can reduce the risk for investors and make it profitable to invest in climate-friendly alternatives.

    Lastly, two main future pathways are identified and discussed, to complement existing infrastructure in the cement industry with carbon capture and electrification of the combustion process, or to restructure the entire production system around alternative binders. The use of carbon capture is easier to introduce into existing infrastructure but is expensive to operate, something that can be improved by combining with electrification of the combustion process. Alternative binders may become cheaper in the long term but require new infrastructure and increased knowledge in the construction industry, as well as updated regulations. Future cement production is likely to combine these strategies.

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  • Glöd, Melinda
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Mårstedt, Hedvig
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Resurseffektivitet inom additiv tillverkning: Undersökning om additiv tillverkning kan implementeras i tillverkningen av reservdelar till kärnkraft2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The report examines whether additive manufacturing could complement the production of spare parts within the nuclear power industry to reduce lead time, storage space, and procurement costs for spare parts. Material properties and resource utilization in additive manufacturing are compared against conventional manufacturing methods. The report describes the advantages and disadvantages of additive manufacturing within the perspectives of inventory management, material quality, and resource efficiency. The purpose is to investigate the profitability of investing in additive manufacturing for companies within the nuclear power industry. The results of the study are derived from both semi-structured interviews and a literature review.

    The results indicate that there are advantages with additive manufacturing, such as the possibility of digital inventories where spare parts can be stored and printed on demand. This will reduce procurement costs and the need to search for a new supplier if the original has disappeared from the market. However, the method is not yet sufficiently regulated for implementation in all parts of the nuclear power industry, as adequate standards for material requirements and properties do not yet exist. Furthermore, additive manufacturing is associated with high production costs and a high defect rate in the produced components.

    In summary, additive manufacturing is a possible solution to address the shortage of spare parts and reduce lead times in aging nuclear power plants. Additive manufacturing together with digital inventories could also reduce the need for large warehouse spaces. However, implementation requires standardization, further development of the manufacturing method, and increased understanding and knowledge.

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  • Kalfas, Anton
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Brifalk Björklund, Jesper
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Möjligheter och utmaningar med automation inom Durgos produktion: Implementering av automationslösningar i mindre företag2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis explores the challenges and opportunities with implementing automation in small and medium-sized enterprises (SME), focusing on Durgo AB, a Swedish company that manufactures valves. As the industries continue to evolve into the framework of Industry 4.0, automation and robotics become more accessible for smaller to medium-sized enterprises. The transition from manual to automated production presents both challenges and opportunities for SMEs.

    The aim of the study is to identify automation solutions for the production at Durgo. The company’s production has mainly manual processes and has a lot of potential for automated implementations. The research methodology includes interviews with Durgo, Scania and Fanuc, on-site observations and literature reviews online.

    The study identifies a concrete example of a potential solution for automation in the production at Durgo. Automating the feeding process for a semi-automated ultrasonic welding cell, currently it requires manual feeding of valves to the welding cell. Automation could free up time as well as the welding could become more efficient for the production. The study concludes that the solution also is scalable and is adaptable across several similar production processes.

    The thesis presents a solution for SMEs like Durgo to begin to implement automation. The study offers insight into how smaller enterprises can harness automation. Not only improving efficiency, but ensures long-term sustainability and competitiveness in a changing industrial landscape.

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  • De Maria Petersson, Emil
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Tidsoptimering i flexibel tillverkning: En litteratur- och fallstudie inom resurseffektiv tillverkning på en högflexibel produktionsanläggning2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor's thesis explores time optimization in flexible manufacturing, focusing on how production efficiency can be improved without reducing the adaptability required in a make-to-order environment. The study is based on both a literature review and a case study conducted at Hestra Inredningar AB, a Swedish manufacturer of customized retail interiors. The literature review covers key concepts in industrial production such as Lean principles, bottleneck analysis, context-aware planning, and scheduling methods like Shortest Processing Time and Part Period Model.

    The case study reveals that Hestra’s production is largely driven by manual planning and individual expertise, which opens opportunities for improvements. Based on interviews, observations, and production data analysis, the study identifies development areas such as enhanced visual planning, data-driven decision-making, and improved order prioritization. A prioritized list of optimization measures is presented, with SPT and context-sensitive planning highlighted as particularly effective strategies. The findings demonstrate that even in semi-automated environments, production lead times can be reduced through systematic changes, without sacrificing the flexibility essential to the company’s business model.

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  • Mebrouk, Mohammed Youcef
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Throne-Holst, Lykke
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Produktionsuppskalning och dess ekonomiska konsekvenser: En studie om omställningen från lågvolyms- till högvolymsproduktion2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Current manufacturing industries are heavily reliant upon effective economic strategy, as such, the implication behind the economical changes during the transition in manufacturing from low-volume to high-volume production is integral for organisations within the manufacturing industry. Hence, the following thesis explores the economical implications in the transition from low to high-volume production, by combining key frameworks in production strategy and layouts, cost structure, and flexibility with empirical insights gathered through interviews and case site visits.

    By utilizing a methodology based on an extensive literature study, supported by a qualitative case study at Volvo AB Köping GTO and first-hand interviews, an analysis of the key cost drivers across production phases has been identified and analysed. The analysis identifies key cost drivers across the production phases; introduction, growth, and maturity – and examines how these change as volume increases. Findings highlight the importance of modular layouts, strategic investment timing, and capacity planning to minimize financial risk during scaling.

    The study emphasizes the value of flexibility and incremental implementation to avoid over-investment and underutilization. By integrating lean principles, cost modeling, and operational KPIs, this report provides actionable recommendations for manufacturing firms seeking to scale efficiently without compromising profitability. The work contributes to a deeper understanding of how companies can align operational expansion with economic viability in volatile market conditions.

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  • Marklund, William
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Liljedahl, Victor
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Innovativa processer i stålproduktionen: En studie av tekniska barriärer och möjligheter för alternativa processer2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report has analyzed the technical challenges and opportunities associated with the transition to fossil-free steel production through the use of hydrogen, while also highlighting potential improvements within the framework of current, established production processes. To address these challenges, a range of solutions is being developed. Some focus on optimizing existing methods, such as by reusing off-gases, recovering waste heat, and integrating carbon capture systems. Other efforts aim to enhance the efficiency of electrolysis systems or to introduce flexible control mechanisms that allow production to be adapted based on electricity prices and energy availability. In parallel, new hydrogen storage technologies are under development, targeting increased energy density, improved safety, and lower costs. These include chemical storage methods, advanced cryogenic techniques, and intelligent monitoring systems.

    Overall, the findings of this report suggest that the energy-related challenges involved in producing green steel are of such magnitude that, at present, it appears more realistic and cost-effective to focus on the gradual improvement of the conventional steelmaking process. By channeling resources and innovation toward making the existing methods progressively more energy-efficient and climate-friendly, rather than fully replacing them with technologies that are not yet mature or economically viable at scale, the industry can maintain its competitiveness while contributing to climate objectives. This approach allows for a balance between the industry’s need for stable and cost-effective production and society’s demand for sustainable development, making it a more pragmatic and feasible alternative in the short to medium term.

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  • Hörman, Anton
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Tichadou Munkhammar, Félix
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Kan man på ett affärsmässigt attraktivt sätt implementera cirkulär ekonomi i mobiltelefonindustrin genom modularisering?2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    With sustainability becoming an increasingly important issue, the interest for circular economy has grown, especially within industries with a short product cycle such as the mobile phone industry. This study explores the possibility of implementing a circular economy through modularization. Modularization is a design strategy where the components that make up the phone are split up into substitutable modules. The work has focused on studying whether modularization is a reasonable strategy to increase the sustainability in the industry, while also discussing how this can be done in a way that's commercially attractive for companies.

    The work is purely theoretical and was conducted through a literary review. Relevant information about circular economy, modular phones and previous attempts in the field was collected through databases such as Scopus, DIVA and Google Scholar. The information that we have gathered through our studies indicates that modularization is a reasonable strategy to increase sustainability, by facilitating repairs, upgrades and potentially prolonging the product's lifespan, as demonstrated by companies such as Fairphone. However, this strategy is unlikely to be commercially attractive in the market within the framework of today’s linear business model. This is because a longer product lifespan reduces revenue from traditional sales. To make modularization in phones economically viable, a broader systemic change and a new business model is needed, such as “Phone as a Service”. In this model, the customer subscribes to the service, the company keeps the ownership of the phone and is responsible for maintenance and upgrades, a process that modularization would facilitate. This would give the company a financial incentive to optimize the product's lifespan and service. This change would require a substantial change throughout the whole industry. The idea has potential, but further research and a thorough economic analysis is needed to fully understand its feasibility and profitability in practice.

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  • Lövdunge Arhin, Nelson
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Dag, Moses
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Omställningen till cirkulär ekonomi inom transportindustrin: en empirisk studie med fokus på krävande incitament2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report explores the ongoing transition from a linear to a circular economy, with a particular focus on the types of incentives that can help companies in the transport sector prioritize and implement circular strategies in their daily operations. The transport industry is one of the most resource-intensive and environmentally impactful sectors in both Swedish and European economies, making it especially relevant to study from a production- and sustainability perspective.

    The work seeks to answer the following research question: What types of incentives – economic, technological, and business-related – are required for the transport industry to prioritize and adopt circular economy principles?

    To answer this question, a qualitative method has been applied, combining a literature review with a case study in the form of a discussion-based interview with Alstom AB, a global leader in the railway sector. The literature review addresses key concepts for understanding the circular economy and its value in humanity’s pursuit of a more sustainable future. The case study offers a practical perspective on how large companies operate with and relate to these concepts.

    The results show that there is a strong and growing willingness among companies to adopt circular strategies. Many of these strategies are already in use, but there is still a long road ahead. The findings also indicate the existence of several obstacles, primarily in the form of high costs, limited access to recycled materials, quality uncertainties, and complex or unclear legislation. The discussion with Alstom AB emphasized that clearer and more concrete regulatory frameworks are among the most critical factors for accelerating this transition.

    The analysis further shows that companies cannot drive this transition alone. A successful shift requires unified collaboration between companies, suppliers, governments, and consumers. However, large corporations within the industry have a unique opportunity to pursue a leadership role by coordinating circular initiatives across the entire value chain, ultimately steering the sector toward a more sustainable future.

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  • Algvere, William
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Källström, Lovisa
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Är Lean produktion en förutsättning för cirkulär ekonomi?: En studie av hur Lean och Cirkulär Ekonomi samverkar med varandra2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    As sustainability becomes an increasingly important factor in the manufacturing industry, this report examines how Lean production and Circular Economy (CE) relate to each other. Lean production has long been used as a strategy to streamline the manufacturing process and eliminate waste, while CE strives to create closed material flows where resources are used as efficiently as possible. The report is based on an extensive literature review and a case study with a docent student and aims to answer the question: Is Lean production a prerequisite for Circular Economy?

    The results show that this is not the case. Lean and CE are separate but compatible systems – Lean can support circular initiatives but is not necessarily a requirement for CE to be implemented. The two systems overlap in some goals, such as resource efficiency and reduced waste, and can be advantageously combined.

    Furthermore, the report's results show that the original question can be usefully reformulated to: Can Lean and Circular Economy complement each other in a manufacturing company? With this formulation, the conclusion becomes a clear yes; they can reinforce each other and contribute to both economic efficiency and increased sustainability.

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  • Koschier, Ludwig
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Generativ AI som verktyg för resurseffektiv produktion: En fallstudie om hur generativ AI påverkar ställtid och konkurrenskraft i tillverkande företag2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Generative AI is used to create new content that resembles content produced by humans. This study evaluated how AI tools such as ChatGPT for Enterprises and Microsoft Copilot for Businesses affect time consumption through a combination of practical tests and interviews conducted in manufacturing companies. In addition, the study explores how GenAI can help ensure product quality, how technical competence is influenced, and how competitiveness is affected. The action research was carried out at Scania’s engine assembly unit, with a focus on documentation work within Scania’s investment process for technical equipment. The results indicate clear time savings when using GenAI, as well as improvements in product quality. For manufacturing companies to benefit from GenAI, a solid understanding of the task at hand and awareness of cognitive pitfalls are required. If users disregard these aspects, the outcome may be counterproductive. When applied correctly, GenAI contributes to enhanced analytical capabilities, improved reviewing, and more efficient project initiation—while maintaining problem-solving ability. Delimitations were made to prevent the study from becoming too broad, in order to enable more concrete conclusions.

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  • Shamon, Issa
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Additiv tillverkning- kostnader och materialspill inom tillverkningsindustrin: En litteraturstudie om lönsamhet, effektivitet och hållbarhetsaspekter vid användning av 3D-printing i industriell produktion2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Additive manufacturing (AM), also known as 3D printing, appears to be an effective technology for improving industrial production by reducing costs and material waste. This study analyzes how AM can replace or complement traditional manufacturing methods to achieve economic and environmental benefits. A comprehensive literature review and several industry case studies (including GE Aviation, Airbus, Tesla, Volvo, and BMW) have been examined. The results show that AM can significantly reduce material waste. For complex components and low to medium production volumes, both production costs and lead times can be lowered. For example, GE reduced the weight of a jet engine component by 25% and increased its lifespan through AM. At the same time, Volvo shortened the manufacturing time for certain assembly tools from 36 days to just 2 days using AM. The study also presents a checklist for profitability analysis, including break-even calculations, life cycle costs (LCC), capital expenditures (CAPEX), and operational expenditures (OPEX), which companies can follow to determine when AM is economically viable. In conclusion, additive manufacturing can contribute to significant cost savings and waste reduction, particularly for complex components and small series, but it is not universally applicable. Companies should therefore perform thorough case-by-case analyses using the proposed checklist before transitioning to AM.

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  • Håkanson, Jonas
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Derwinger, Jonathan
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Utmaningar och möjligheter med omställningen till cirkulär ekonomi inom europeisk personbilindustri: Hur påverkas lönsamhet, kvalitet och resurseffektivitet med fokus på rekonstruktion och återanvändning2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The European passenger car industry faces a comprehensive transition from a linear to a circular economy to meet demands for increased sustainability and resource efficiency. This report analyzes the challenges and opportunities arising from this transition, with particular emphasis on remanufacturing and direct reuse of vehicle components.

    The results show that circular methods can significantly reduce environmental impact, primarily through decreased emissions, reduced material consumption and energy use. However, several challenges are identified, including organizational barriers within corporate management and economic uncertainty due to initial costs and uncertain links to profitability. Additional challenges include ensuring logistical flows and the impact of the design phase on remanufacturability.

    The report also highlights economic opportunities associated with circular business models, such as product as a service and an increased share of remanufacturing in the product lifecycle. These models can potentially enhance profitability by retaining added value over a longer period, by increasing both utilization rates and product lifespan.

    The conclusion is that the passenger car industry can greatly benefit from accelerating the transition to a circular economy where remanufacturing and direct reuse serve important purposes from both an environmental and economic perspective. Strategic efforts are required from both industrial stakeholders and political decision-makers to overcome existing barriers, which in turn promotes remanufacturing and direct reuse as circular strategies.

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  • Desai, Nivedi
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Yilmaz, Özcan
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Resurseffektiv gruvdrift i norr: En analys av LKAB:s verksamhet i Kiruna2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report examines how LKAB’s mining operations in Kiruna impact energy usage and the environment, as well as analyzing existing and potential sustainability strategies to mitigate these effects.

    The analysis shows that LKAB’s mining operations entail significant energy demand and affect both local and global environmental aspects, particularly related to water pollution, greenhouse gas emissions, and high energy demand due to the energy intensive processes involved in iron ore mining and pellet production. It is also evident that the company has already undertaken several successful initiatives to reduce environmental impacts, in which energy efficiency, electricity and the use of fossil-free electricity play a central role. Projects such as HYBRIT, where LKAB collaborates with SSAB and Vattenfall to produce fossil-independent iron and steel, are highlighted as groundbreaking examples of the sustainable transformation of the mining industry. Additionally, Sandvik plays an important role by offering new technological solutions for electrified, automated mining equipment as well as smarter mine-planning that reduces both energy consumption and environmental impact. The findings also indicate that digitalization and automation create new opportunities to further streamline mining operations through process optimization, as well as remote monitoring and control. It becomes evident that the future of mining will require a more integrated strategy, combining technological solutions with circular economic principles, improved water and waste management, and sustainable energy supply.

    Overall, the study shows that LKAB has taken important steps towards more sustainable and circular mining operations, but that continued collaboration, technological developments, and investments will be crucial to meet future demands for a climate-neutral mining industry, in which stricter environmental laws and regulations may also serve as a catalyst for faster transition and innovation development.

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  • Bonnarp, Mathias
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Ekblom, Gustaf
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Resurseffektivisering av vattenskärning: Hur kan vattenskärning optimeras för att minska resursförbrukning och öka hållbarheten inom industrin?2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Waterjet cutting is a versatile machining technique used across many different industries. The technology enables cutting through both soft and hard materials without causing thermal impact or residual stresses in the material. Waterjet cutting offers several advantages, such as high precision, good cut quality, and a low risk of damage to the processed material. Hence, there are challenges related to resource usage, particularly concerning water, energy, and abrasive materials.

    This project investigates resource efficiency in waterjet cutting, with a focus on how the use of water and abrasives can be optimized to reduce both economic and environmental costs. The authors also analyze the potential for recycling water and abrasives, as well as the development of new technologies to improve efficiency, for example through the use of electric pumps and enhanced filtration systems.

    The analysis is based on a literature review and a site visit to a waterjet cutting machine manufacturer ending with an interview. The chosen method aimed to provide a deeper understanding of waterjet cutting, compare existing knowledge with current research, and explore opportunities for improving resource efficiency within the technology.

    The study shows that water is a relatively inexpensive resource in Sweden, but that there are still significant opportunities to reduce water usage through more efficient pumps. Recycling abrasive materials is also an important aspect, but the processes required to clean and reuse the material are still very energy-intensive, making cost-efficiency difficult to achieve.

    When compared to other cutting methods, such as laser cutting and plasma cutting, waterjet cutting shows advantages in cutting thicker materials and sensitive components. However, it can be more resource-demanding, especially in terms of energy consumption and the use of abrasives.

    The report concludes with recommendations for future research and technological innovations to further reduce resource consumption and increase sustainability in waterjet cutting.

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  • Almsara, Abdulrzak
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Undersökning av effekten av arbetsmiljön på konkurrenskraften för nätverksorganisationen med hjälp av systemdynamiskt tillvägagångssätt2025Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Network organizations, particularly in manufacturing, face increasing pressures to enhance their competitiveness in the ever-evolving landscape of modern industry. The integration of artificial intelligence (AI) and automation technologies offers both opportunities and challenges, reshaping how employees collaborate and perform tasks. However, successful integration of these technologies requires more than just technical implementation, it demands organizational transformation, including trust-building, leadership transparency, and employee involvement. This study explores the interplay between physical, organizational, digital, and employee factors within networked manufacturing organizations, focusing on how AI and automation affect productivity, employee engagement, collaboration, and overall competitiveness. Through a comprehensive literature review and analysis, the research highlights trust as the key enabler of successful digital transformation, facilitating cross-functional communication, organizational cooperation, and employee adaptability. The findings reveal that trust is not only essential for overcoming resistance to AI but also for aligning technological initiatives with long-term organizational goals.

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  • Peterson, Gustav
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Wang, Kevin
    KTH, School of Industrial Engineering and Management (ITM), Production engineering.
    Optimeringsdilemmat: Den svenska industrins positionering i optimeringsdilemmat beroende på dess produktionsfilosofi2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study was conducted to investigate how Swedish industry relates to various production strategies, specifically Lean production, Agile production, and the sandcone model. These three strategies were compared based on the production attributes of flexibility, productivity, and quality. The positioning of Swedish industry in relation to these attributes was determined through two interviews, which provided quantitative data. The data was subsequently analysed using an appropriate quantitative model developed in MATLAB. The resulting model represents what is referred to in this report as the optimization dilemma (see title page). Based on the obtained results, potential patterns and tendencies within Swedish industry were discussed in connection to the selected production strategies. Comparisons with existing academic literature were also made to provide a broader perspective beyond the two conducted interviews.

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  • Nyman, Hannes
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Lateral-Torsional Buckling in Crane Runway Girders: A Comparative Study of Different Standards2025Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis presents a comparative study on the design of crane runway girders, focusing on lateral-torsional buckling of beams with welded I-shaped sections. With increasing investment from both the private and public sectors in northern Sweden’s industrial development, the design of crane structures has become increasingly important. The study evaluates and compares how lateral-torsional buckling is addressed in three design standards for crane runway girders: the current Eurocode (SS-EN 1993-6:2007), the upcoming Eurocode (FprEN 1993-6:2025), and the American standard (ANSI/AISC 360-16).A previously designed runway girder was analysed using both analytical and numerical methods. The analytical calculations were carried out in Mathcad Prime 10 for each design standard and verified through finite element analysis in IDEA StatiCa. The previously designed runway girder was then modified by varying its cross-sectional heights as well as testing different lateral restraint configurations to assess its influence on lateral-torsional buckling.The results show significant differences in how conservative the design standards are. The current Eurocode is complex and uses a lot of modification factors, while the upcoming Eurocode and American standard are simplified and use less modification factors. The key differences in moment factors, reduction factors, and interaction formulas were identified and discussed. The study concludes with recommendations for improving the upcoming Eurocode by incorporating aspects of the American standard and a guidance for structural engineers regarding lateral-torsional buckling in the design of crane runway girder.

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  • Boström, Simon
    et al.
    KTH, School of Engineering Sciences (SCI).
    Morner, David
    KTH, School of Engineering Sciences (SCI).
    Rocket Engine Oxidizer Valve Flow Dynamics2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Initiating the combustion process in a hybrid rocket motor using pyrotechnic ignition has a riskof extinguishing the flame and thus the engine. To avoid this, a much lower flow rate can beintroduced before opening the main valve supplying oxidiser to the combustion chamber. Thisthesis investigates the possibility of integrating the pre-flow and fully opened stages in a singlevalve using an orifice plate design concept and quantifying how the diameter and geometry of suchan orifice will affect flow rate and cavitation. With experimental data to validate a simulationsetup, we used the k-omega SST turbulence model in ANSYS Fluent to find an expression for massflow through an orifice dependent on geometry. The effect of the orifice geometry on cavitationwas also brought to light. Results showed that mass flow rate can be increased when enlarging thediameter as well as when rounding the orifice inlet geometry. On top of this, the results show thatthe mass flow can be sufficiently predicted using Computational Fluid Dynamics and the SinglePhase Incompressible model assumption with certain pressure-based boundary conditions.

     

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  • Appeltofft, Christoffer
    KTH, School of Engineering Sciences (SCI).
    Utformning av ett tyngdpunktsförskjutningssystem med roterande excentriska vikter2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna artikel presenterar utformningen och utvecklingen av ett trimsystem fören undervattensrobot, kallat TCG (Transversal center of gravity trim system),som syftar till att justera robotens tyngdpunkt för att förbättra dess balans ochprestanda. Projektet omfattar utformningen av trimsystemet, inklusive val avmotor, drivsystem och vikter samt de tekniska och mekaniska övervägandensom påverkar systemets funktion. CAD-modellering och simuleringar använ-des för att optimera konstruktionen och säkerställa att systemet uppfyllde degeometriska och prestandamässiga kraven. En ny konstruktion valdes där engimbalmotor placerades centralt med en excentrisk vikt monterad på den. Vik-terna består av en trumma fylld med volframkulor som roterar för att juste-ra tyngdpunkten. Systemet har simulerats för att flytta tyngdpunkten inom ettberäknat område. Dessutom beräknades effektförbrukningen och batteritiden,vilket visade en minimal påverkan på robotens totala energianvändning. Trim-systemet konstruerades med 3D-utskrivna delar tillsammans med motorerna.Ett Python-program utvecklades för att beräkna och styra motorerna till denangivna rotationen utifrån masscentrums position. Konstruktionen begränsa-des till en bredd på 90 mm och ett inre skrov på 115 mm. Vikterna kan verkapå undervattensroboten med 155 mN m per sida och förbrukar totalt 12 W i denmest krävande positionen.

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  • Nässén, Brasse
    KTH, School of Engineering Sciences (SCI).
    Viskoelastisk och plastisk deformation i pressboard för transformatortillämpningar2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Den ökade elektrifieringen av samhället har lett till större belastning på elnätet och dess olika delar. En av de berörda delarna är transformatorerna som fyller den väsentliga rollen att antingen transformera elen till högspänning eller lågspänning. Transformatorer är komplicerade konstruktioner som består av många komponenter. En av dessa komponenter och den som undersöks i detta arbete ska undersöka är en stapel med ett ledande material, oftast koppar och ett isolerande material, i många staplar är det isolerande materialet ett cellulosafiberbaserat material som kallas pressboard. Vid monteringen av denna stapel blir materialen klämda med en specifik klämspänning som beror på det förväntade användningsområdet, beräknad livslängd och dess beräknade belastning. Vid för låg eller minskande klämspänning ökar risken för haveri och liknande mekaniska brott vid bland annat stora impulser som kan orsakas av till exempel kortslutningar. Anledningarna till att stapelns klämspänning skulle minska är flera men kommer i denna rapport att begränsas till det isolerade materialets påverkan. 

    Arbetet består i att skapa en matematiskmodell av materialet pressboard som verifieras med hjälp av experiment. Detta utfördes genom att skapa en modell, av materialet där det initialt är linjärelastiskt och sedan utvecklas för att ta hänsyn till viskoelasticitet, plasticitet och möjligen porositet i ett ojämnt ytskikt på pressboardens yta. Denna yta dimensioneras separat och är även den baserad på experimentell data som används genom att efterlikna ytans deformation till de experimentella resultaten. 

    Resultatet visar att en materialmodell vars egenskaper efterliknar experimenten kan skapas och till viss nivå ha en god noggrannhet. Modellen överskattar alltid den elastiska avlastningen eftersom den utgår från den initiala elasticitetsmodulen och inte beaktar att elasticitetsmodulen ökar då porositeten i materialet minskar vid tryckbelastning. Dock finns det plats för förbättring i modellen, bland annat kan plasticitetens styvhet modelleras bättre för att få en bättre anpassning till mätdata. Skillnaden mellan deformationerna om pressboard modelleras som ett isotropt eller ortotropt material är liten och har försummats, därför har en isotrop modell använts. Dock hade en ortotrop modell varit mer relevant och avbildat verkligheten bättre. 

    I kandidatsexamensarbetet har verifierats att den framtagna modellen kvalitativt kan förklara deformationen i pressboard vid varierande kompressionsbelastning vilket var syftet med arbetet

     

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  • Ek Sjödin, Malcolm
    et al.
    KTH, School of Engineering Sciences (SCI).
    Wiss, Björn
    KTH, School of Engineering Sciences (SCI).
    Simulation av en vinklad mutterdragare modellerad som en elastisk balk2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Inom ramen för detta projekt, konstruerades och testades två simulationsmodeller för en vinklad mutterdragare från Atlas Copco, baserade på Euler-Bernoullis balkteori. Målet var att bestämma storheter relaterade till rörelse vid verktygets handtag samt uppkomna reaktionskrafter i operatörens hand-arm-system, modellerat som ett enfrihetsgradigt massa-fjäder-dämpar-system. Tidigare arbeten har modellerat verktyget som en stelkropp, varför detta arbete syftade till att undersöka hur införd elasticitet i verktyget kan tänkas påverka det dynamiska förloppet. Resultaten visar att simulationernas naturtrogenhet troligen förbättras genom att betrakta elasticitet i verktyget, men arbete kvarstår för att helt verifiera detta.

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  • Agarwal, Daniel
    et al.
    KTH, School of Engineering Sciences (SCI).
    Larssen, Björen
    KTH, School of Engineering Sciences (SCI).
    Finita differensmetoder för elastiska vågekvationen i två dimensioner2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I den här rapporten diskuteras olika sätt att lösa den elastiska vågekvationen. Förskjutningsformuleringen och hastighet-spänningsformuleringen jämförs och löses numeriskt med olika typer av finita differensapproximationer. Förskjutningsformuleringen löses med centrala differenser i både rummet och i tiden. I hastighet-spänningsformuleringen utnyttjas möjligheten att använda förskjutna rutnät för de olika variablerna. Detta jämförs med icke-förskjutna rutnät där man i varje nätpunkt räknar ut alla variabler. Möjligheten att applicera olika randvillkor i de olika formuleringarna jämförs. Dessutom undersöks noggrannhet och beräkningshastighet för de olika metoderna.

    Samtliga metoder har andra ordningens noggrannhet och felen med förskjutna rutnät blir mindre än med icke-förskjutna. Vi observerade även att hastighet-spänningsformuleringen gav upphov till "taggiga" lösningar med icke-förskjutna rutnät, detta syntes inte med förskjutna rutnät. Vidare är hastighet-spänningsformuleringen att föredra, framförallt vid användning av spänningsfria randvillkor.

     

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  • Bawer, Arslan
    et al.
    KTH, School of Engineering Sciences (SCI).
    Löf, Aleksi
    KTH, School of Engineering Sciences (SCI).
    Estimating team form in football using Hidden Markov Models2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To predict what tomorrow brings, is it reasonable to assume only the present isrelevant?

    This report will focus on understanding and evaluating the implementation ofHidden Markov models (HMMs) for predicting a football team’s form. HMMs areuseful in systems where the true state - in this case, a team’s performance trend,or form - is hidden, and must be inferred from some observable output, such asin this case; expected goals (xG). The purpose of the model is to then unveil theprobabilities which govern transitions between hidden states, and how likely eachstate is to produce a particular observation. To achieve this, the probabilities areestimated through an expectation-maximization algorithm.

    For this project, the training data for the model consisted of games that spanseveral seasons, from 2020 until 2025; with a focus on applying it to a team thatretained the same manager throughout the period, ensuring a relatively consistentplay style. Arsenal F.C in the English Premier league (EPL) was chosen. Thisallows us to assume the process is time-homogeneous meaning the probabilitiesassigned by the model are constant over time.

    The model was subsequently refined by selecting the most appropriate number ofhidden states, followed by an analysis evaluating its predictive accuracy and howwell it fits the historical data.

    This study demonstrates that it is possible to capture underlying long-term formtrends in football using HMMs, as for predictive power in the short term, it failsin beating a naive baseline.

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  • Hoffman Carlsson, Olle
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology.
    Impact of Electric Vehicles on Equipment in a Local Electrical Distribution Grid2024Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Electric Vehicle (EV) charging can strain power systems and grid equipment by increasing electricity demand. It is vital for grid operators to understand the possible impacts of EVs on their grids to continue safely operating the equipment. Therefore, this study examines the potential effects on the equipment in a distribution grid consisting of 36 secondary substations due to increased electrification in the light duty transport sector. It also assesses two charging strategies: cost optimization and peak valley filling.

    Findings show that uncoordinated charging negatively affects the equipment but with variations across the electric grid. At 50% Penetration Level (PL), two transformers approach their maximum capacity threshold, and with further increases in EV numbers, more transformers tend to reach their peak load capacity. At 75% and 100% PL, two respectively four transformers become overloaded. The results also indicate that the electrical lines (maximum of 23.5% capacity) and the voltage drops (minimum 0.978 p.u.) are safely within the acceptable range.

    The cost optimization charging approach primarily shifts charging to nighttime, reducing maximum transformer loads. Still, one transformer reaches maximum capacity at 75% PL; and two at 100% PL. The peak-valley filling strategy consistently maintains transformer load at 71.5%, effectively flattening the demand curve.

    In conclusion, unregulated charging results in increased electricity demand, especially during peak hours. As such, it could potentially limit EV adoption without grid investments. Smart charging can effectively optimize electricity use, which reduces the need for equipment upgrade.

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  • Odeberg, Axel
    KTH, School of Engineering Sciences (SCI).
    Design av lutningsstyrd cykelsimulator - Förstudie och koncept2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Simulering är för forskning inom fordonsteknik ett ovärderligt verktyg vars användning är ständigt ökande. Detsamma gäller urvalet av fordonstyper som realistiskt kan simuleras, däribland cyklar och dess dynamik, säkerhet, och beteende i trafiken har börjat studeras med ökande intresse. På avdelningen för fordonsdynamik på Institutionen för Teknisk Mekanik vid KTH Campus Stockholm finns redan en rörelsebaserad körsimulator med gränssnitt för bilar. Denna rapport beskriver en förstudie som utfördes för att utvärdera tillvägagångsätt för att konstruera en cykelsimulator, gärna med den befintliga maskinvaran som utgångspunkt. Ett av de huvudsakliga målen är att mekanismen ska tillåta cykelns fria lutning sida till sida, för att kunna använda detta som en indata i simuleringen. Denna grad av rörelse innebär vissa särskilda begränsningar och krav på konstruktionen, vilka denna studie arbetade med att identifiera och lösa.

    Utifrån designspecifikationer, geometriska begränsningar, mekaniska approximationer och tidigare arbeten inom området erhölls en ny aktuatorkonfiguration med bland annat utökad slaglängd för att kunna simulera centripetalkrafter av realistisk amplitud. Inbromsningar, lutningar i vägen och gupp kunder också återskapas med ett enda system undertill på plattformen, vilket i praktiken möjliggör simulering i alla 6 frihetsgrader. En drivlina med simulerat rullmotstånd och ett modulärt gränssnitt för fästning av cyklar av olika storlek och geometri utvecklades också. För att konkretisera konceptet ytterligare och illustrera möjliga tekniska lösningar skapades en grundläggande modell av den nya designen i Solid Edge.

    Innan en verklig konstruktion kan realiseras krävs ytterligare geometri- och kraftanalyser av cyklar och simulatorkonceptet, samt vidareutvecklig med avseende på aspekter som hållfasthet, användarsäkerhet och tillverkning. Potentiella metoder för att tillgodose eller minska behovet av extrema slaglängder för aktuatorerna bör också undersökas.

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  • Ciambella, Christian
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Modellering av plattrambroar ur ett bärighetsperspektiv: En jämförelse mellan linjära och icke-linjära analysstrategier2025Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis investigated how different analysis strategies influence the load-carryingassessment and plastic redistributions capacity of existing concrete portal frame bridges. Theassessment was based on the Swedish Transport and Administration’s (Trafikverkets)classification system, expressed as A- and B-values. Using these values as starting pointslinear and nonlinear analyses have been performed. The bridge was modelled as a one-meterwidestrip with the use of the finite element software SOFiSTiK FEA 2025.With the help of the idealized modeling, corresponding to a one-meter-wide strip, a simpleand effective way to evaluate the analysis levels was made possible. While still not neglectingto capture the key mechanism associated to linear and nonlinear analysis in a reliable manner.The results showed a significant reserve capacity compared to the linear analysis that could beexploited through the nonlinear analysis, mainly because of the analysis attribute to accountfor material plasticity and moment redistribution. In the nonlinear analysis, the A-valueincreased by up to 40 % and the B-value by up to 25 % compared with the linear analysis.In the linear elastic analysis, the mid-span moment exceeded the corner moments. The resultsalso shoved a substantial moment redistribution from the span to the corners, 21 % for the Avalueand 12 % for the B- value when shifting from linear to nonlinear analysis. This providesincentives to consider nonlinear analysis if the mid-span moment governs the linear analysis.The results aligned well with previous findings, which increased the reliability. While alsohighlighting the importance of verifications throughout the analyses, as nonlinear results areharder to verify compared with linear ones.The thesis also investigated how key portal frame bridge parameters impacts the load-carryingcapacity and the moment redistribution. The investigated parameters, including concretestrength class, reinforcement amount and its placement. The sensitivity analysis showed thatthe reinforcement properties have a major impact on the capacity, while the concrete strengthclass has comparable minor effect.Overall, this thesis demonstrated that simplified nonlinear analysis can give valuable insightswhen performing load carrying assessments of portal frame bridges, especially when linearmethod has proven to be insufficient, while emphasizing the need of clearer guidelines andsafety formats for nonlinear analyses.

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  • Hagman, Axel
    et al.
    KTH, School of Engineering Sciences (SCI).
    Rennerfelt, William
    KTH, School of Engineering Sciences (SCI).
    Förbättring av återkoppling vid simulerad kontinuerlig inbromsning2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Forskargruppen Fordonsdynamik på Kungliga Tekniska Högskolan, KTH, har konstruerat en körsimulator som i dagsläget främst ger föraren återkoppling av ett fordons lateraldynamik samt initial återkoppling i längsled vid acceleration och inbromsning. I nuläget saknas återkoppling till föraren av kontinuerlig inbromsning vilket kan leda till en minskad realistisk körupplevelse, opålitliga testresultat och simulatorsjuka för användaren. 

    För att leverera känslan av kontinuerlig inbromsning till föraren krävs ett nytt system som möjliggör den dimensionen i simuleringen. Syftet med denna rapport är att undersöka, analysera och presentera en lösning för att ge föraren en realistisk återkoppling vid kontinuerlig inbromsning i KTH´s körsimulator. Detta innefattar att identifiera och utvärdera möjliga tekniska lösningar samt uppskatta de krafter som krävs för att efterlikna en verklig inbromsningsupplevelse. 

    Arbetet inleddes med att genomföra en kortare litteraturstudie som syftade till att söka relevant information för att fastställa ett beslut angående vilket typ av system som löser problemformuleringen. Därefter dimensionerades systemet med hjälp av en kraftmodell, kördata från simulatorn samt riktlinjer från motorproducenten Aratron. I kombination med en principiell konstruktion för systemet resulterade denna dimensionering i ett förslag på vilken modell av motor som bör användas.

    Arbetet visar att ett bältessträckarsystem är en lämplig lösning för detta problem. Utifrån modellantaganden har en förenklad kraftanalys genomförts där krafterna användes för att dimensionera motorn till systemet. Efter dimensioneringen fastställdes det att motorn DMS14-5 från Aratron uppnår de två huvudsakliga kraven som är att systemet ska kunna leverera tillräckligt stor kraft och att det har tillräckligt snabb kraftutveckling. Därmed är DMS14-5 ett lämpligt alternativ trots en viss överdimensionering. Utöver detta undersöktes motorn DMS12-5 som endast uppnådde de eftertraktade kraven i samband med en approximativ omskalning av systemets krafter för att bättre anpassas till en simulatormiljö.

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  • Säll, Anton
    et al.
    KTH, School of Engineering Sciences (SCI).
    Molin, Henric
    KTH, School of Engineering Sciences (SCI).
    Energiförbrukningen vid framdrivning av ett Hyperloopsystem2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Transportsektorn står för en stor del av den globala uppvärmningen och miljöförändringen som präglar världen. I Sverige kommer en stor andel av utsläppen av växthusgaserna från vägtransporter och flyg. För att lösa detta problem är det bra att utforska alternativa transportmedel som kan uppfylla samma behov utan att skapa lika mycket utsläpp.

    Hyperloop är ett transportmedelskoncept som består av ett magnetsvävartåg i en nära-vakuumtunnel för att minimera motståndskrafter vid drift. Detta låter poddar åka med väldigt höga hastigheter samtidigt som de förbrukar förnybar energi. Hyperloop kan på detta vis minska koldioxidutsläppet av långa resor genom att vara bekvämare än flyg samt snabbare än tåg och bilar.

    I denna rapport undersöktes energiförbrukningen hos ett Hyperloop-system vid färd från Stockholm till Malmö. Modellen var baserad på det tyska Transrapid som använder en linjär synkronmotor (LSM) för drivning och elektromagnetisk suspension (EMS) för svävning. Magnetiska och aerodynamiska motståndskrafter har använts för att beräkna energiförbrukningen för resan vid varierande topografi, marschfart och acceleration. Beräkningarna byggde på vissa förenklade antaganden om motståndskrafter samt körfall.

    Resultaten visade att topografin hade en försumbar inverkan på energiförbrukningen för det testade körfallet. Man kan då argumentera att Hyperloop-tunnlarna bör byggas längs topografin. Marschfarten hade en stor påverkan på mängden energi som krävdes för en resa, medan accelerationen mest påverkade dragkraften som motorn behövde leverera. För att optimera energikonsumtion och motorns dragkraft krävs det ett lämpligt val av marschfart och acceleration. 

    Energiförbrukningen för Hyperloop-systemet var väldigt likt X2000-tåget. Dock inkluderade beräkningarna inte andra elektriska system som t.ex. ljus, ventilation och tryckreglering i tunnlarna. Därför bör den totala energiförbrukningen av hela systemet vara mycket större än resultatet visade.

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  • Blomgren, Anton
    et al.
    KTH, School of Engineering Sciences (SCI).
    Sjöö, Isak
    KTH, School of Engineering Sciences (SCI).
    Sentient Driven Stock Prediction: Modeling News Articles' Impact with Logistic Regression and Neural Networks2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The objective of this thesis is to investigate the relationship between newssentiment and stock market performance by predicting daily stock pricemovement for Tesla (TSLA). Sentiment data from news articles for a longer period(3.1) is used to construct features based on average sentiment and trend (3.2).These features are then used to train two different models: logistic regression (2.2)and a feedforward neural network (2.3), both aiming to predict whether the stockwill go up or down on a given trading day.Two different periods are tested spanning from 2022 until 2025. Across all tests,the neural network is the only model beating random, with an average accuracy of0,58 and and average ROC-AUC score of 0,59 (4.2). The logistic regression modelhas successful classification for the first period, while overall performing no betterthan average (4.1).This study does give insight into the relationship between expressed opinions innews articles and the resulting stock movement, but the analysis is only executedon a chosen stock for a chosen period, thus no generalized conclusions can bedrawn from this study alone.

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  • Tillberg, Mattias
    et al.
    KTH, School of Engineering Sciences (SCI).
    Otterheim, Andreas
    KTH, School of Engineering Sciences (SCI).
    Är Steer by Wire redo att ta över ratten?2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna litteraturstudie undersöker möjligheten att implementera Steer by Wire teknologi i personbilar på ett sätt som bevarar en styrkänsla och säkerhet jämförbar med traditionella mekaniska styrsystem. Steer by Wire ersätter den mekaniska kopplingen mellan ratt och hjul med elektroniska komponenter, vilket möjliggör fördelar såsom viktminskning, ökad designflexibilitet och bättre integration med autonoma system. Avsaknaden av naturlig haptisk återkoppling samt systemets beroende av elektronik innebär dock utmaningar när det gäller förarupplevelse och säkerhet. I rapporten analyseras hur styrkänslan kan återskapas artificiellt genom haptisk återkoppling, adaptiva styralgoritmer och signalbehandling. Säkerhetsaspekter behandlas också, inklusive redundans i aktuatorer och sensorer, fail-safe-mekanismer samt cybersäkerhet. Studien visar att dagens teknik kan efterlikna många funktioner hos mekaniska styrsystem, men att ytterligare utveckling inom säkerhetsarkitektur och användaracceptans krävs innan en bred introduktion av Steer by Wire i personbilar är möjlig.

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  • Granryd, Elliot
    et al.
    KTH, School of Engineering Sciences (SCI).
    Jonsson, Anders
    KTH, School of Engineering Sciences (SCI).
    Dimensionering och provning av brottbult för Södertälje sluss2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I detta arbete har en anslutning mellan slussport och ställdon utformats till södertälje sluss. Anslutningens syfte är att skydda ställdonet från att ta större skada vid en eventuell kollision av ett fartyg och ska därför gå till brott då en kollision inträffar. \newline Brottmekanismen i anslutningen har utformats som en tredelad solid cylinder av rostfitt stål med två särskiljande skjuvplan där en brytpinne per skjuvplan har placerats som ska ta upp skjuvkrafter. \newline Dessutom har en testrigg utformats för att kunna utföra ett förstörande prov av brottmeknaismen. Slutligen har en FEM-analys genomförts av \newline brottmkenismen. Resultatet av FEM-analysen visar att brottbulten ej går till brott vid den tänkta belastningen. Slutsatsen av detta arbete är att den undersökta lösningen inte rekommenderas då den inte uppfyller samtliga krav som ställs på lösningen. För att brottbulten ska gå till brott vid den önskade kraften krävs andra dimensioner av brytpinnarna eller andra material, där dessa modefieringar medför att konstruktioen ej uppfyller det krav som ställs enligt urdraget från Eurokod 1993 1-8 respketive att införandet av andra material medför en risk för galvaniska ellement.

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  • Ek, Alfred
    et al.
    KTH, School of Engineering Sciences (SCI).
    Ehinger, Charlie
    KTH, School of Engineering Sciences (SCI).
    Dimensionering av skruvförband för längdjusteringsögla på Öhlins S46 dämparserie2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna rapport behandlar en längdjusterare på en dämpare från Öhlins som används ivissa sportmotorcyklar. Syftet är att undersöka om den nuvarande M17x1-gängkopplingenkan ersättas eller modifieras för att klara flera typer av belastningar: ett maxlastfall, ettutmattningsfall samt ett draglastfall. Målet är att ta fram en lösning som uppfyller kra-ven för samtliga belastningsscenarier.Analysen fokuserar på att undersöka olika varianter av skruvförbandet genom attjustera gängdiameter och gängstigning. De studerade gängorna är M16x1, M17x1,M18x1, M20x1, M20x0.5 och M20x1.5. Förbandet består av en skruv, en låsmutteroch en ovanmutter, det vill säga ett skruvförband utan inledande klämlängd, vilket vi-sade sig vara en väsentlig begränsning och orsakade problem under projektets gångbåde eftersom större delen av den teori som fanns online och på sidor såsom AnsysLearning Hub riktade sig mot skruvförband med klämlängd, samt eftersom det krävdeen införd cylindrisk klämlängd där funktionen bolt pretension i ansys kunde införas.Samtliga analyser genomfördes i ANSYS Workbench med modulen Static Structu-ral. Utgångspunkten var det befintliga förbandet, som sedan modifierades i flera vari-anter med avseende på gängdimensioner. För att säkerställa resultatens tillförlitlighetgenomfördes gränsvärdesstudier för att identifiera eventuella singulariteter eller mo-dellfel.Resultaten visade att ingen av de testade gängvarianterna, varken genom ändringav diameter eller stigning, kunde uppfylla samtliga krav. Även ett alternativ där bric-kor infördes för att skapa en klämlängd analyserades, men inte heller detta scenariouppfyllde hållfasthetskraven.Under arbetets gång identifierades ett flertal brister i modellen som bedöms ha på-verkat resultaten negativt. Bland förbättringsåtgärder som föreslås för framtida arbetemärks:• Placering av den införda klämlängden mitt mellan låsmuttern och ovanmuttern.• Ändra snittet där applicerad kraft för maxlast och draglast införsEn fortsatt utveckling av modellen, med ovanstående förbättringar, bedöms kunnabidra till mer verklighetstrogna och tillförlitliga resultat.

     

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  • Lins, Oskar
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Real Estate and Construction Management.
    Bohlin, Fabian
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering.
    Ontologier och kunskapsgrafer: Mot en semantiskt datadriven byggbransch2025Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    While being one of the least digitalized sectors, the construction industry is facing increasing demands for more efficient information management and digital collaboration. This master’sthesis explores how semantic technologies, in the form of ontologies and knowledge graphs, can support more structured, traceable and interoperable data management in construction projects. Through a combination of literature review and semi-structured interviews with both industry professionals and researchers, the study analyzes the potential to implement these technologies. The findings show that these tools offer concrete opportunities for improved decision support, knowledge reuse, automated compliance checking and more efficient project management. Simultaneously, several challenges related to organizational culture, leadership, competence and lack of standardized processes emerge. The study therefore emphasizes the importance of understanding these technologies not merely as technical solutions but also as part of a broader organizational transformation.

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  • Reisch, Lea
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Mattsson, Louise
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Utvärdering av Motorway Control System på E18 Danderyd - Arninge: En analys av framkomlighet, trafiksäkerhet och kollektivtrafikens punktlighet2025Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Efficient and safe roads are crucial for a well-functioning transport system, especially in metropolitan areas where congestion, incidents and capacity shortages are challenges. Accessibility problems can lead to rear-end collision accidents, increased journey times and socio-economic costs. 

    This study focuses on the motorway E18 between Danderyd and Arninge, in Stockholm Sweden where Motorway Control System (MCS) and a bus lane measures have been introduced in 2021 and completed in 2022 with the aim of improving traffic flow and increasing road safety. This study aims to evaluate the effects of these measures on accessibility, accident rates and public transport punctuality, as well as highlight future developments linked to new advanced driver-assistance systems. The analysis is limited to the March and October 2024 rush hours and is based on transport policy objectives and road safety principles, such as Vision Zero. The data sources used are speed data from MCS portals, samples from previous speed measurements on the route, accident statistics from STRADA and punctuality data from SL. The analysis of the traffic flow is based on comparisons with samples before implementation and data from MCS portals after implementation. Days with accidents have been identified and analyzed separately. For public transport, the punctuality in 2024 has been compared to the corresponding data from 2019 for the bus lines operating the route and compared to the punctuality of the entire traffic area during the period.

    The results of the study do not show any clear improvement in traffic flow after the implementation of MCS, however, a lower average speed can be measured in comparison with samples from before implementation of MCS, which may indicate an adaptation to the speed limits. Parts of the road section still have a lack of capacity in the direction towards Stockholm during the morning and towards Arninge during the afternoon. For public transport, punctuality has improved for the bus lines operating on the route where MCS and bus lanes have been introduced in comparison with other lines in the traffic area. The results show that MCS has potentially had a positive impact by limiting the impact of incidents on the road. The number of rear-end accidents has a decreasing trend after the introduction of MCS, but it is not possible to say that this is a result of the implementation or a long-term trend.

    The conclusion is that neither MCS nor the bus lane has had the desired effect of stabilizing traffic flow and speed on the route. There are indications of a reduced number of rear end accidents on the route, but it is not possible to determine whether this is due to MCS. The improved punctuality of public transport is largely due to the construction of the public transport lane, although other external influences may be present. Future technological developments, such as advanced driver-assistance systems, may replace some of the functions of today's MCS, particularly in preventing rear-end collisions. Therefore, the implementation of new MCS systems should be evaluated on a case-by-case basis, based on local conditions, needs and existing technologies.

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  • Österling, Rebecka
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Ossmyr, Josefin
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Building Technology and Design.
    Energieffektivisering i kontorsfastigheter: Strategier för minskad energiförbrukning och förbättrad energiklass2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Improving energy efficiency in existing office buildings is a key part of the transition to a sustainablebuilding stock. This thesis addresses three key questions about technical measures,cost-effectiveness, and future digital management.First, a new strategy is presented to integrate future readiness and AI into energy efficiencywork. The strategy is based on a review of current practices at several well-established propertycompanies and interviews with AI researchers. These researchers describe several barriersthat hold back progress, including a lack of accessible and standardized data, seasonal variations,and challenges connecting AI models to existing control systems. The new strategy providessolutions and outlines what property owners can do today. It serves as a guide for propertyowners and AI developers who want to prepare buildings for the future and improve energyefficiency.Second, the study examines how measures within heating and ventilation systems affect energyperformance and operating costs. The analysis is based on the reference building Furudal2, provided by Castellum. The building is an office property from the 1980s with an energyrating of D. Through energy mapping, site visits, and calculations, measures such as solar panelsand adding a ground-source heat pump to the existing district heating system are identified.Investment calculations show that several of these measures are cost-effective and could upgradethe building to energy class C. This could also open the door to green financing.Third, the potential of AI-based control systems is explored through literature and interviews.The study shows that AI has strong potential to optimize energy use and adjust operations tothe building’s needs. However, the technology is currently limited by low levels of digital maturity,poor data quality, and challenges integrating AI solutions with existing control systems.Overall, the study demonstrates that improving energy efficiency requires both technicalmeasures and a clear strategy for digitalization. The results offer practical advice for propertyowners looking to upgrade their buildings’ energy ratings, lower operating costs, and preparefor the future.

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  • Humam, Kasyful
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Modelling Autonomous Demand Responsive Transport (DRT) For KTH Campus2025Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis explores the network design and simulation of an Autonomous Demand Responsive Transport (DRT) system for the KTH Royal Institute of Technology campus in Stockholm, Sweden. The study addresses current mobility challenges within the campus, particularly to the Albanova campus, which has limited accessibility. Using a data-driven approach, the research integrates e-scooter trip data and SL smart data for public transport to construct an O-D matrix characterizing mobility demands within the campus.

    A simulation framework was developed using VIPsim, allowing for the evaluation of multiple dispatch and routing algorithms under varying fleet sizes and demand scenarios. Five algorithms were tested across morning and afternoon peak periods, with performance assessed based on key indicators such as average waiting time, vehicle utilization, and passenger service rates.

    Results show that DRT can significantly improve campus mobility, offering a flexible and efficient transportation alternative, particularly in serving the Albanova campus. During morning peak hours, 15 vehicles were enough to achieve reasonable waiting times, while only 10 vehicles were needed for afternoon peak hours. However, in the afternoon peak hour, 10 vehicles were not enough to minimize waiting time according to user preference of less than 5 minutes; therefore, increasing vehicle capacity is necessary.

    In terms of algorithm performance, the Max Pass algorithm, which assigns vehicles based on maximizing the number of passengers, performed best in both the morning and afternoon peak hours compared to the Min Max algorithm, which assigns vehicles based on minimizing waiting time.

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  • Abban, Kweku
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Transport planning.
    Metro platform crowding:: Why do passengers choose a specific section of the platform to board a metro train?2025Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Crowding on metro platforms and uneven passenger distribution across train cars pose significant challenges to both passenger comfort and operational efficiency in urban transit systems. In Stockholm’s metro system, these issues are especially pronounced during peak hours, leading to prolonged boarding times and passenger dissatisfaction. This master’s thesis investigates the influence of Real-Time Crowding Information (RTCI) on passengers’ platform section choices through a stated preference experiment. By simulating scenarios with and without RTCI on onboard vehicle crowding, the study evaluates how passengers adjust their boarding positions in response to real-time information, considering key factors such as walking times, platform crowding, and trip purpose.

    The results indicate that providing RTCI about vehicle crowding significantly alters passenger behaviour, encouraging redistribution along the platform and reducing clustering in crowded sections. Notably, passengers’ sensitivity to platform crowding and walking times changes once RTCI is available, shifting their focus toward avoiding crowded train cars. These findings underscore the potential of RTCI as a practical, cost-effective crowd management tool to improve passenger flow and train loading patterns without costly infrastructure expansion.

    The study contributes new insights into platform-level decision-making, emphasizing the behavioural processes behind boarding choices. It also provides practical implications and suggestions for transit operators seeking to implement real-time information systems to enhance passenger experience and service reliability. Further research could expand on these findings using advanced modelling techniques and by exploring diverse metro environments.

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  • Jonsson, Fredrik
    KTH, School of Engineering Sciences (SCI), Physics.
    K-Edge Imaging in Photon-Counting Spectral CT2025Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The spectral capability of photon-counting computed tomography enablesK-edge imaging, that is, material decomposition with one or several highatomic number contrast agents with K-absorption-edges (K-edges) in thediagnostic X-ray energy range. This opens up for new simultaneous multi-contrast imaging applications. This thesis investigates the feasibility andlimitations of several dual-contrast imaging cases using different contrast-agent pairs, through simulations of a silicon-based photon-counting compu-ted tomography system performed using CatSim. Specifically, a maximum-likelihood three-material decomposition method based on an empirical ra-tional forward model was implemented, where water and the two contrastagents, investigated for the given case, were set as the basis materials. Themethod was then applied to simulations of slabs and analytical phantoms ofthe basis materials to evaluate the material decomposition performance. TheCNR in the resulting reconstructed material images was evaluated as themain figure of merit. The investigated cases in this thesis were: Iodine (K-edge at 33.2 keV) and gadolinium (50.2 keV), iodine and barium (37.4 keV), gadolinium and barium, iodine and xenon (34.6 keV), gadolinium and xenon,and iodine and krypton (14.3 keV). The material decomposition was suc-cessful with good performance for the cases with contrast agents that havewell-separated K-edges. The CNR in the material images was strongly affec-ted by the size of the simulated phantom and the imaging dose (mAs). Theresults for the iodine and krypton dual-contrast imaging case were especiallypromising for application in perfusion-ventilation CT to identify pulmonaryembolisms. The material decomposition performance for the cases with closeK-edges (iodine and barium or xenon) was much poorer, although with moreeffort, it might still be possible.

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  • Höglund, Johan
    KTH, School of Engineering Sciences (SCI), Physics.
    Analysis of the polarimeter motion on XL-Calibur using the onboard alignment camera2025Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis investigates whether the backwards-looking camera (BLC) onboard the balloon-borne hard X-ray mission XL-Calibur can be used to compensate for the dynamical motion of the X-ray mirror focal point, whose dynamical nature is due to gravitational and thermal effects on bending the 12 m long telescope truss. The motion is measured by detecting the position of 15 LEDs arranged in two concentric circles around the polarimeter aperture. A software program has been written to locate these LEDs and independently verify and complement the work already done by the onboard flight software of XL-Calibur. The values obtained by the two programs overlap in the temporal regions where coincident measurements were made. The motion of the X-ray focal point could then be modelled and parametrised using the values obtained from the flight software to produce an almost event-by-event correction for the focal point. The resulting correction, when applied to the XL-Calibur data, changes the polarisation results in a non-statistically significant way. This suggests that the previous correction offset obtained by using the average photon position on a pixilated detector at the rear end of the polarimeter is a good approximation for the true offset. Further work is needed to conclude if no meaningful improvement can be made to the systematic errors by using the BLC and to better relate the mirror aim point to the measured average photon detection point.

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  • Haglund, Alexander
    et al.
    KTH, School of Engineering Sciences (SCI).
    Sanner, Eric
    KTH, School of Engineering Sciences (SCI).
    Design av LCG-trimsystem för autonom undervattensrobot2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Ett batteripaket som även fungerar som longitudinellt trimsystem för en undervattensrobot SAM (Small and Affordable Maritime Robot) har designats, dimensionerats och testats. Systemet kombinerar energilagring och massförskjutning för att öka energitäthet och effektivitet. Batteripaketet består av 30 litiumjonceller av typen 21700 i konfiguration 5P6S, vilket ger en nominell spänning på 21,6V och en uppskattad kapacitet på 540 Wh. 

    Batteriet kan leverera en kontinuerlig ström på upp till 20 A och en maximal ström på 30 A. Battericellerna kan förskjutas så att ett moment motsvarande 143 kg$\cdot$mm uppnås med en hastighet om 30 mm/s. Trimsystemet drivs av en stegmotor med remdrift till en kulskruv som förskjuter battericellerna och styrs av en mikrokontroller med avståndssensor. 

    Prototypen testades både elektriskt och mekaniskt. Resultaten visar att prestandan uppfyller kraven utan överhettning. Trimsystemet fungerar även vid vertikalt läge utan risk för att batteriet fastnar eller kilas fast eller kulskruven knäcks. Dessutom uppnås en stationär position i vertikalt läge utan stegmotorn behöver strömförsörjas. Vidare arbete behövs för att förbättra tillverkningsprocessen i att svetsa och löda battericeller, samt undvika termisk deformation av 3D skrivna delar.

     

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  • Alexis, Albin
    et al.
    KTH, School of Engineering Sciences (SCI).
    Nordqvist, Hugo
    KTH, School of Engineering Sciences (SCI).
    Development of a software tool for analysis of data from a sensor network designed to measure radon levels in ground water2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report explores radon concentrations in groundwater with a focus on performing an effective data analysis tool for the sensor data. An increase in radon concentration in groundwater is believed to have a connection with increased seismic activity. By developing a methodology for visualizing and extracting important data, the objective is to improve the understanding of potential correlation of increased seismic activity and higher radon concentration. With this methodology the analysis tries to correlate parameters such as temperature and pressure to an increase in radon levels. As a result, possible correlations between radon levels and environmental parameters have been studied. As well as a functional software tool with a user-friendly interface to support ongoing analysis and visualization. Energy histograms provided important insights for identifying sensor performance issues, while radon count trends across geographical locations helped distinguish sensor behavior. Currently, no correlation between the radon levels and parameters like temperature/pressure is observed. Data collection over a longer time is needed for reaching conclusions.

     

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  • Rafiq, Darian
    et al.
    KTH, School of Engineering Sciences (SCI).
    Shammo, Aboud
    KTH, School of Engineering Sciences (SCI).
    Termisk analys av Hyperloop: Utmaningar och lösningar2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Detta examensarbete undersöker de termiska utmaningarna i framtida Hyperloop-transportsystem där höga hastigheter och vakuummiljö ställer specifika krav på värmehanteringen. Genom en kombinerad litteraturstudie och numerisk simulering i MATLAB analyseras hur värme genereras i systemet, särskilt från motorer, levitation, assagerare och interna faciliteter, samt hur denna värme kan avledas. Studien visar att konventionella kylmetoder är otillräckliga i vakuummiljöer eftersom konvektion blir verkningslös och strålning istället utgör den dominerande värmeöverföringsmekanismen. En två-nodsmodell utvecklas för att simulera temperaturfördelning och energi flöden i poddens struktur och luft. Resultaten visar att passiv kylning med is kan fungera men är opraktisk eftersom cirka 2% av poddens volym krävs för att hålla temperaturen inom rimliga nivåer. Även andra passiva metoder, såsom kylflänsar, presenteras men deras effekt är begränsad av vakuumets låga konvektionskapacitet. Därför krävs en aktiv kylmetod såsom evaporations- eller sublimationskylning för att på ett effektivt, hållbart och praktiskt sätt hantera överskottsvärmen. Arbetet identifierar även viktiga faktorer för utformningen av framtida kylsystem i Hyperloop med särskilt fokus på energieffektivitet och hållbarhet.

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  • Malmqvist, Tove
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering.
    Borgström, Sara
    WSP.
    Brismark, Johanna
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Erlandsson, Martin
    IVL Svenska Miljöinstitutet.
    Reference values for embodied carbon of Swedish building construction2023In: Proceedings of the International Conference “Sustainable Built Environment and Urban Transition”, Växjö, 2023Conference paper (Refereed)
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  • Pasichnyi, Oleksii
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Resources, Energy and Infrastructure.
    Thibault, Sacha
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Malmqvist, Tove
    KTH, School of Architecture and the Built Environment (ABE), Sustainable development, Environmental science and Engineering, Sustainability Assessment and Management.
    Whole Life Carbon Assessment of Buildings at Urban Scale2024Conference paper (Refereed)
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  • Bratt, Knut
    KTH, School of Engineering Sciences (SCI).
    Reaktivitetsförändringar från härdskador i kokvattenreaktorer2025Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    En skadad reaktorhärd är viktig att studera för att skapa förståelse kring svåra haveriförlopp i kärnkraftsreaktorer. En härds reaktorfysikaliska beteende kan beskrivas med reaktivitet, ett mått på hur antalet neutroner mellan varje generation förändras. Med beräkningskoden Polaris i kodpaketet SCALE kan kärnbränslepatroners egenskaper vid olika tillstånd simuleras i 2D. Syftet med detta arbete är att undersöka hur reaktivitet förändras, exempelvis i en bränslepatron av typ SVEA-100, genom att variera diverse parametrar och geometrier för att återspegla en skadad härd där nedsmältning av olika strukturer har undersökts. Bland annat används data från beräkningar med programmet MELCOR, som är ett beräkningsprogram för vad som kallas integral analys av svåra haverier, (eng. integral severe accident analysis). MELCOR innehåller modeller för diverse kemiska och fysikaliska fenomen vilket möjliggör analys av olycksförlopp med stora skador på reaktorhärden. MELCOR beräknar exempelvis hur och när diverse delar av härden skadas, om delar av härden smälter, var härdmaterialet hamnar och hur mycket. Den data som erhålls från MELCOR-beräkningar har sedan tolkats för att bygga modeller i Polaris för att kunna beräkna reaktivitet som funktion av olika tillståndsförändringar. De reaktorfysikaliska parametrar som beräknas av Polaris kan i sin tur användas för att dels direkt göra enkla approximationer och dels för framtida beräkningar i härdberäkningsprogram, som PARCS, SIMULATE eller POLCA.

     

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