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ANALYZING THE DISTURBANCES IN A MANUFACTURING COMPANY
No full textThe Order to Delivery (OTD) process plays a critical role in manufacturing, directly impacting
lead times, production efficiency, and customer satisfaction. Since the COVID-19 pandemic,
the studied company, an established manufacturer, has struggled to restore pre pandemic
OTD performance levels. The number of products deviating from the Standard Activity
Process (SAP) has more than doubled since 2019, primarily due to an increase in postproduction adjustments, reworks, and component shortages.
This thesis aims to identify the most frequent and impactful disturbances within the OTD
process by analyzing both qualitative and quantitative data collected from internal databases
and interviews with key stakeholders. Structured around the three main OTD phases: Order,
Industrial, and Market. The study applies a data-driven case study approach supported by
theoretical frameworks including Lean Manufacturing and Six Sigma’s DMAIC methodology.
The thesis does not seek to determine root causes but instead maps and quantifies the
disturbances that consistently challenge OTD stability. Additionally, it visualizes what an
“optimal flow” could look like if the process operated without disruptions. The findings provide
the company with clear guidance on where to focus future improvement efforts to enhance
responsiveness, reduce non-value-adding activities, and approach ideal performance
standards
End-of-Life Pathways for Beverage Packaging An LCA study on the Swedish deposit system, conventional recycling and incineration with energy recovery
No full textIn line with the EU Directive on Packaging and Packaging Waste (PPWD), a fundamental
shift in how packaging is designed and managed is required to reduce
environmental impacts and support the transition to a circular economy. This master’s
thesis conducts a life cycle assessment (LCA) of waste management systems
for PET bottles and aluminium cans in Sweden. The systems studied are Returpack’s
deposit system, conventional recycling, and incineration with energy recovery.
The study aims to investigate the environmental impact of each system based on
four categories, in accordance with the LCA methodology. The study seeks to highlight
the most significant processes by identifying key environmental hotspots across
the systems and provide practical recommendations for promoting more sustainable
packaging waste management in Sweden.
The study shows that the deposit system generally results in the lowest environmental
impact, as it enables closed loop recycling and maintains high material quality.
Incineration with energy recovery generally has the highest environmental impact.
In all investigated impact categories, the recycling process is the largest contributor
to the deposit and conventional recycling systems’ environmental impact. A
common factor contributing to the environmental impact across the three PET systems
is the incineration of PET that cannot be recycled, along with other residual
waste generated in the processes. Regarding aluminium cans, the high electricity
consumption within the recycling process in the deposit system and the addition of
metals in the conventional recycling process are the main contributors to the systems’
environmental impact.
Differences in collection rates and consumer behavior between the systems were
not fully accounted for, despite their potential to influence environmental impacts.
Future studies should investigate these aspects to provide a more comprehensive
assessment. The results highlight the importance of preserving material quality,
efficient sorting, and technological advancements. Recycling is shown to be an effective
strategy for a circular economy, particularly when implemented as closed loop
recycling, as in the deposit system. This approach keeps materials in use longer and
reduces the demand for new virgin resources.
Keywords: Life Cycle Assessment, LCA, Circula
Framtidens behov av integrerad display på värmepumpar
No full textThis thesis investigates the future need for an integrated display on heat pumps with a focus on user experience. The study is conducted in collaboration with NIBE
and is based on their S-series that offers both an integrated display and an app for communicating with the heat pump.
The aim is to evaluate whether a physical display is necessary for future heat pumps and how the interface design influences usability and long-term functionality. The
research includes interviews with consumers and installers, a user survey, market analysis and a brief sustainability assessment.
The results show that user needs vary depending on technical interest and experience. Apps are valued for their flexibility and remote control capabilities while the integrated display provides reliability and security during connectivity issues. Therefore, both the display and app are recommended to be available for future heat pumps. The user interface should be intuitive, offer different user modes and provide clear information regarding settings and system status. Additionally, alignment between the app and display interfaces is crucial to ensure consistency and ease of use.
The conclusion is that an integrated display remains essential for ensuring user friendliness and reliability, but should be complemented with an app to meet different user need
Systematic Design and Integration of Large Language Model Tools for Engineering Analysis
No full textGenerative AI, and more specifically large language models (LLMs), show great
promise in further facilitating and streamlining analysis engineering work. In this
thesis, the current limitations for the use of such technologies regarding the incorporation
in engineering tasks are investigated. This investigation consists of a
comprehensive literature study, in addition to nine interviews with engineers at GKN
Aerospace in Trollhättan, Sweden. The results indicate a number of challenges. One
being the importance of embedding internal company knowledge when leveraging
the capacities of LLMs, while the use of non-local LLMs is linked to considerable issues
when it comes to handling sensitive data. With the results of this investigative
study as a foundation, an LLM-based tool meant to mitigate these identified issues
is developed. The development is done using LangChain, such that the OpenAI
API can be used in a Python environment. The developed software is focused on
the manipulation, and extracting, of data in CNS files. A file format containing results
from finite element simulations. Different agentic systems, leveraging different
methods for knowledge embedding such as retrieval augmented generation (RAG),
and post-training such as fine-tuning, are investigated. The various architectures
are evaluated based on their efficiency and accuracy in solving tasks. The results
indicate that LLM-based tools have great potential in the field. The top performing
architecture based on this testing is incorporated into a sub-graph architecture,
for which usability and validation are examined. The results for efficiency, accuracy,
usability testing and validation imply the considerable potential of leveraging
LLMs in the domain. Nevertheless, performance is not perfect and a number of
considerations in such a development must be taken. The methods for knowledge
embedding and post-training seemingly have great impact on the performance, and
more sophisticated approaches within RAG and fine-tuning have potential to further
improve performance
Enhancing feasibility analysis through LLMs: An Action Research Approach
No full textRequirement elicitation is a critical part of Requirements engineering (RE). However, it is heavily reliant on the knowledge of domain experts, is prone to human-errors, and remains a time-consuming process. This study investigates how Large Language Models can assist domain experts in conducting feasibility analyses of customer demands. Specifically, the study investigates two different solutions as an LLM; the Retrieval-Augmented Generation (RAG) architecture, and the finetuned pre-trained LLM. The two models were developed using the action research methodology in collaboration with Siemens Energy AB. All the data used for training the models were related to historical gas turbine projects and were provided by Siemens Energy. The findings showed that the finetuned LLM struggled with ambiguous requirements and was prone to hallucinate for a certain type of customer demands, in particular demands that were covered by Siemens Energy’s standard. In contrast, the RAG demonstrated a higher accuracy and relevance in its outputs. The two models were evaluated through a survey, which was answered by the domain experts at Siemens Energy. The surveys revealed that both of the models have potential as a decisionsupport tool, but that the RAG was preferred since it outperformed the finetuned LLM in all of the metrics. Lastly, a finetuned embedding model was developed as part of the RAG solution. This embedding model was quantitatively evaluated and compared to state-of-the-art models. This evaluation showed that the fine-tuned model outperforms state-of-the-art benchmarks on the intended task and in the environment of Siemens Energy
Simulerad produktionsmiljö med robotarmar och rullband: Utveckling av ett automatiserat system för färgsortering av lådor
No full textAutomation is a major part of the future of manufacturing, enabling factories to efficiently produce and deliver products and services. As the industry strives for higher efficiency and reduced production costs, automation has increased in demand. In sorting processes, automation can help reduce the reliance on manual labor, which in turn can lead to increased precision in the manufacturing process as well as improvements in the working environment for employees.
This project investigates the possibility of automating the sorting of boxes using two robotic arms placed between two conveyor belts. The goal was to develop a compact system capable of identifying the color of boxes and sorting them based on predetermined criteria. The system was constructed using sensors, servos, conveyor belts, and custom-built robotic arms. Several tests were conducted to evaluate the systems precision and performance, including tests that pushed the system to its limits.
The results of the tests showed that the system met the predetermined requirements. At higher conveyor belt speeds, more errors occurred with the robotic arms, indicating that higher speeds negatively affect reliability. In addition to conveyor speed, the systems ability to maintain consistent precision is also affected by the quality of the sensors and servos used.
In conclusion, it is possible to create a system with robotic arms and conveyor belts to sort boxes based on color. However, improvements and higher quality components are needed to increase the systems precision and stability. Such a system can be scaled up and has potential applications in logistics and packaging industries. The system can also be used for educational purposes to demonstrate principles in fields such as mechatronics and automation
Processes in management of food traceability: A cross-case study between Spain and Sweden
No full textIn a world where consumers demand greater transparency and safety in the food they eat, traceability has become a critical part of modern food systems. Regulations across the European Union have made food and fish traceability a legal requirement, but the way these rules are implemented can differ significantly from one country to another. This thesis explores how public authorities in Spain and Sweden manage traceability through administrative and logistic processes, providing a practical perspective on how theory and legislation are translated into real action.
The research adopts a qualitative case study approach, based on interviews with representatives from government agencies responsible for traceability enforcement in both countries. The aim is to understand how inspections, documentation, coordination, and control mechanisms are used in practice, and how these differ between a centralized model like Sweden’s and a decentralized structure like Spain’s. The study also reflects on the human side of traceability; how communication, trust, and professional judgment play key roles in ensuring that systems work as intended.
Findings reveal both common challenges and contrasting approaches. The study highlights that successful traceability depends not only on strong regulations and modern tools, but also on the people and institutions behind them. By offering a comparative and grounded view, this research contributes to a deeper understanding of how food safety is managed in practice, and how future improvements can be guided by both structure and experience
Impact of Environmental Factors on Breakdown Characteristics of Air Insulation in Power Distribution Components of Electrical Aircraft
No full textAbstract
Growing concerns on environmental issues challenge scientists and engineers to create greener technologies on a vast area of industrial and commercial applications. Aviation, as one of the major human activities responsible for the environmental impacts, is among the most trending topics in this effort for transition to more eco-friendly technologies.
While electrical aircraft have been experimented from as early as 1885, achieved by Gaston Tissandier by flying a small airship powered by an electric motor, the scale of aircraft needed today is significantly larger. The more powerful electrical powertrains needed to achieve this goal call for higher levels of system voltage to reduce the weight and enable competitive designs.
Although well-studied for land and sea applications, the use of high voltage systems is a relatively new area for aviation systems. A growing demand for research and development is emerging for creating regulations, technical standards, testing methods and know-how for applying high voltage solutions in electrical aircraft.
This thesis explored the implications of implementing high voltage direct current systems to be used in hybrid or all-electric electrical aircraft with a focus on the performance of the dielectric systems under expected ambient conditions in high altitudes, namely extreme ambient temperatures (TA), low air pressure (p) and various relative humidity (RH) levels.
To achieve the goal, experimental setups of vacuum and climate conditioning chambers were utilized to create ambient conditions an electrical aircraft may experience, and respective breakdown voltage for the insulation system for various scenarios were measured.
It was observed that lower air pressure and relative humidity levels create unfavorable conditions for the insulation system, while lower ambient temperature increases the breakdown voltage. The combined effect of higher altitude conditions was evaluated to be of performance depreciative nature for the insulation systems as the altitude increases up to 25,000 feet. It was also concluded that significantly lower insulation performance may emerge around the dew point of water in the air
Development and Optimization of Photopolymerizable Binders for Lithium-Ion Battery
No full textThe demand for faster, energy-efficient, and cost-effective lithium-ion battery (LIB) manufacturing has necessitated innovations in electrode binder technology. Conventional binders such as PVDF (polyvinylidene fluoride) and SBR-CMC (styrene-butadiene rubber and carboxymethyl cellulose) require prolonged thermal curing processes, contributing significantly to production time and energy consumption. This study introduces a novel photopolymerizable binder system based on N-Phenylmaleimide copolymerized with 4-Styrenesulfonic acid sodium salt hydrate (4SN), N-Phenyl-p-phenylenediamine (NPN), and 5-Aminoisophthalic acid (5AN), initiated by a BAOP Phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide -based photoinitiator. The synthesis, UV-curing process, and application on aluminum current collectors are detailed. Binder-coated electrodes were cured under 365 nm UV light and subjected to minimal thermal treatment. The resulting electrodes were evaluated against conventional PVDF-based electrodes using FTIR, SEM, peel adhesion tests, potentiometric analysis, and comprehensive electrochemical characterization including cyclic voltammetry and charge-discharge cycling. The UV-cured binders demonstrated enhanced adhesion, efficient polymerization, reduced processing time, and competitive electrochemical performance, highlighting their potential for scalable LIB productio