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Senast publicerade
- Further Application of Progressive Verification(2026) Heljeberg, Mia; Nyberg, ArvidA digital signature is a fundamental cryptographic primitive that provides authenticity and integrity by allowing anyone with a public key to verify that a message was produced by a signer with a corresponding secret key. Such verifications typically produce a binary output only when the process is finished. In contrast, progressive verification (PV) performs verification in smaller incremental steps, gradually building confidence in the signature’s validity over the course of the process. Progressive verification offers several key advantages for post-quantum cryptographic (PQC) schemes on resource constrained devices as it allows for early rejection of invalid inputs and supports adjustable soundness (allowing for a trade-off between security and efficiency). Furthermore, PV can shrink the public key size which addresses a common challenge of PQC schemes. This thesis explores the design and applicability of PV on post-quantum secure digital signature schemes currently involved in the NIST PQC standardisation process. The approach utilises a compiler framework developed by Boschini et al [1] which transforms matrix-vector based (Mv-style) verifications into progressive ones. We explore whether this approach extends to further multivariate quadratic (MQ) schemes as well as to code based schemes. In addition, we investigate whether the compiler can be applied to zero-knowledge proofs, thereby addressing the broader applicability of progressive verification beyond digital signatures. By identifying the matrix-vector structure in the schemes and analysing how the compiler interacts with the verification steps, we assess correctness preservation, security aspects, and practical feasibility. Our findings show that the PV compiler applies cleanly to the MQ-based scheme Unbalanced Oil and Vinegar (UOV), enabling gradual verification without modifying the signing or key-generation algorithms. For code-based schemes, we demonstrate that PV is not applicable to the Codes and Restricted Objects Signature Scheme (CROSS), despite it containing a matrix-vector multiplication in the verification. Progressive verification was also shown to be partially applicable to the verification of a zero-knowledge proof. Overall, this thesis expands the set of post-quantum digital signature schemes known to support progressive verification and highlights design features that make a scheme compatible with PV. These insights can guide both future implementations of PV and the development of new PQC schemes intended for constrained environments.
- Visualizing Forestry Operators’ Work - ForReel: Supporting harvester operators’ professional identity in an increasingly automated industry(2026) Wang, Chia-An; Einarsdóttir, Eva SifThe forestry industry in Sweden is highly automated, and this trend is accelerating day by day. While this technological shift increases efficiency, it introduces the risk of operator deskilling, a diminished autonomy with subsequent demotivation and disengagement. This thesis explores how increasing automation impacts the professional identity of harvester operators and investigates how Interaction Design can be used to support it. In collaboration with the User Experience department at Volvo Penta, this challenge is addressed by applying a Research-through-Design method to identify the core elements that construct an operator’s professional identity. The double-diamond design process resulted in a highlight reel system–ForReel, intended to preserve the operators’ professional identity by making their real work visible both for self-reflection and to others for more social recognition. This design concept utilizes multimodal data collection, fusing mechanical data with biometric sensors and manual inputs, to capture moments of exceptional operational skill, for example, difficult-terrain navigation, deliberate overrides of algorithmic suggestions, and flow states. The concept was first evaluated through an online survey with a storyboard, and then field tests were conducted using a Wizard of Oz simulation. The key feature of a highlight reel received positive feedback from participating harvester operators. The findings suggest that Interaction Design interventions can potentially sustain harvester operators’ professional identity by translating abstract production metrics into clear, shareable proof of their invisible expertise.
- Performance Bottleneck Evaluation of llama.cpp on Jetson and H100(2026) Yu, Mingqi; Tang, YifanEfficient large language model inference depends strongly on the interaction between workload shape, numerical precision, serving configuration, and hardware platform. This thesis evaluates the performance bottlenecks of llama.cpp on two contrasting NVIDIA platforms: the datacenter-class H100 GPU and the edge-oriented Jetson AGX Orin. The study uses Llama 3.1 8B models in BF16, Q8_0, and Q4_K_M formats, and separates inference into prefill and decode phases using controlled single-sequence workloads and concurrent serving experiments. The evaluation first establishes baseline performance across balanced, prefill-heavy, and decode-heavy workloads. It then applies targeted profiling with Nsight Systems, server-side timing logs, and power measurements to explain the observed behavior. On H100, the results show a stable phase-dependent precision trade-off: BF16 is most effective for long-prefill workloads because execution is dominated by optimized BF16 GEMM and attention kernels, while Q4_K_M is more favorable for decode-heavy workloads where execution shifts to repeated matrix-vector kernels. Flash Attention further improves long-prefill throughput, but has a smaller effect on decode. On Jetson Orin, the dominant tuning problem is different. Performance and energy efficiency depend strongly on the selected power mode. The results show that 50W provides a strong energy-oriented operating point, while MAX mode gives the highest throughput and lowest latency. Orin also shows power-mode-dependent precision behavior: Q8_0 remains competitive at lower power, while Q4_K_M becomes more favorable for decode at higher power modes. Concurrent serving experiments further reveal a trade-off between throughput, energy per token, and time to first token. Overall, this thesis shows that inference optimization cannot rely on a single global configuration. Instead, effective deployment requires phase-aware, platform-aware, and power-aware tuning. The final guidelines recommend precision, Flash Attention, power mode, and concurrency settings based on the dominant workload and deployment objective.
- Error and Reliability Analysis of Open Source LLMs for Text-to-SQL Generation Across Query Complexities(2026) Alizade, Mojtaba; Younes, OmarRetrieving the correct data from databases quickly and accurately using Structured Query Language (SQL) is a crucial task in Software Engineering, but one that is time-consuming if done manually, and complicated to navigate if done through an application. However, asking a specific question about the database in natural language and using a Large Language Model (LLM) to generate a SQL query that retrieves the desired data is more time-efficient and intuitive for practitioners. This Text-to-SQL process is nonetheless difficult for LLMs, as it requires high-reasoning and domain-knowledge capabilities. This study aims to gain a better understanding for failures of LLMs in this context by exploring how the complexity of a Text-to-SQL task, and the active parameter count of LLMs, affect the type of failures, how often they occur, and how consistent the failure rates are. To achieve this, three randomly sampled sets of Text-to-SQL questions of different complexities from the BIRD and LiveSQLBench-Base-Lite datasets are run on the Qwen3 A3B, Qwen3 A22B and Qwen3 A35B LLMs via Amazon Bedrock using a two-step prompting strategy. The results are first analyzed descriptively and then statistically tested. The results show that selecting the correct tables to use in the generated query is the most common subcategory of failure observed across LLMs, that increases in size between the selected LLMs do not significantly affect performance on any complexity, and that none of the examined LLMs are significantly different in failure reliability across complexities. With that being said, all three LLMs achieve absolute failure consistency, in at least 76% of the Text-to-SQL questions, indicating that failures are likely systematic due to an inability to produce a correct answer.
- Is Engagement the Key to Reduce Empty Snus Containers in Nature? - Comparing Motivational Strategies for Reducing Snus Container Plastic Waste(2026) Arntouk, Taofik; Giaro, JuliaPlastic waste continues to pose a significant environmental challenge. With incorrect disposal contributing in pollution in both urban and natural environments. In Sweden, disposable snus containers represent a recurring plastic waste stream due to high user consumption rates and their frequent disposal in combustible waste or incorrectly in public spaces. Existing recycling systems often rely on digital applications and additional user effort, which could result in unnecessary mental load, which can cause friction and reduced participation. This thesis explores how interaction design and behavioral motivation strategies can be used to encourage more engaging recycling behaviors for empty snus container recycling in public spaces. The research was grounded in research through design and followed an iterative design process which involved literature studies, surveys, prototyping, testing, and public deployment. Two different motivational strategies for recycling were explored: gamification and nature-based, which resulted into two high-fidelity prototypes: the Snus Ballot Voting prototype and Gacha Machine prototype. User feedback and field observations indicated that playful, physical, and socially visible interactions contributed to user engagement and participation during recycling activities. Indicating that the importance of intuitive and tangible interactions could have an impact in public recycling systems. Due to the practical constraints and limited research duration, the monetary and charity based incentive could not be fully implemented or evaluated. Future work should further investigate long term deployment and the motivational strategy that this thesis did not cover to be fully implemented within the scope of this research.