Chalmers Open Digital Repository

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  Simulation-Based Metamorphic Testing for System Verification of Cyber-Physical Systems - A Systematic Assessment of Seamless EV Charging Systems Under Dynamic Conditions

  (2026) Cronvall, Oscar; Pettersson, Linus

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  The increasing adoption of electric vehicles has driven demand for reliable public charging infrastructure, as well as the backend software systems that support it. Seamless charging services, which link charging sessions to vehicles by correlating asynchronous event streams from charge point operators and vehicle systems, introduce a verification challenge that conventional testing approaches are not well suited to address. There is no precomputable ground truth against which each matching decision can be evaluated, and reproducing relevant adversarial conditions through physical testing is not feasible at scale. This thesis presents the design, implementation, and evaluation of a simulation based metamorphic testing framework that addresses these constraints. The frame work combines discrete-event simulation, which generates realistic and adversarial event sequences in a reproducible execution environment, with metamorphic relations, which act as a substitute oracle by defining behavioral properties that must hold across related executions. Eight metamorphic relations that characterize correct vehicle-to-session matching behavior were derived through a four-step process consisting of source code analysis, brainstorming, peer review with the development team, and consolidation. The framework was evaluated against the Seamless Charging Service operated by WirelessCar AB across 18 scenarios. The simulator generated 467 validation reports. Six of the eight metamorphic relations held across the dataset, while two, matching exclusivity and match quality monotonicity, revealed 43 violations across 11 reports. These violations were traceable to structural inconsistencies in the system’s observed behavior, despite the system producing zero incorrect matches across 998 attempted matches. No confirmed false positives were observed across 397 control executions. The findings demonstrate that simulation-based metamorphic testing can detect meaningful behavioral deviations in event-driven cyber-physical systems without access to a traditional test oracle. At the same time, the strength of this conclusion is bounded by the conditions the framework was able to execute: the densest concurrency and event ordering scenarios did not complete within the configured execution budget, leaving the system’s behaviour under the highest-stress conditions unverified.

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  Waste-to-Energy in a Destruction Oriented System

  (2026) Gullberg, Alexandra; Sjöstrand, Lukas

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  Energy recovery from waste is often discussed as a way to address environmental pressure, resource inefficiency, and electricity insecurity at the same time. In South Africa, however, the possibility of developing waste to energy, WtE, from healthcare risk waste, HCRW, incineration raises a more complex question. Existing incinerators already perform a necessary treatment function, but they were designed to destroy hazardous waste safely, not to recover energy. This thesis therefore examines whether the surrounding system can support a shift from destruction-oriented incineration toward WtE. The study applies a Technological Innovation Systems, TIS, framework and is based on a qualitative embedded single case study of Averda’s South African HCRW treatment activities. The analysis draws on interviews, site visits, field observations, and secondary documents, including material from the case company, regulators, experts, technology suppliers, and other relevant industry actors. The empirical material was analysed through iterative thematic analysis and subsequently interpreted through TIS structures, functions, and inducement and blocking mechanisms, with attention to the justice implications of the pathway. The findings show that the system contains some conditions that could support WtE development, including existing incineration infrastructure, operational experience, technical knowledge, and policy attention to waste and energy challenges. However, these inducements remain weak. The system is primarily organised around safe destruction, compliance, and treatment continuity rather than energy recovery. WtE development is constrained by weak market formation, unclear electricity offtake conditions, limited experimentation, ageing and manual plant infrastructure, restricted resource mobilisation, and continued dependence on established waste management practices. The thesis concludes that WtE from HCRW incineration in South Africa is technically conceivable but systemically constrained. Under current conditions, it should not be understood as an imminent or scalable electricity generation pathway, but rather as a conditional and site specific energy recovery option within a destruction oriented system.

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  What Makes a Leader Stand Out?

  (2026) Alnahi, Mirna; Staaf, Rasmus

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  This study examines how leadership is interpreted, evaluated, and justified in an evaluative context by analyzing student assessments of award-winning leaders. The study is based on 232 student reports produced between 2017 and 2025 within a master- level leadership and communication course at Chalmers University of Technology. In the reports, students analyzed four leadership nominees using theoretical frameworks and justified which leader they considered most deserving of a leadership award. Using a qualitative, interpretive, and abductive research design inspired by Gioia methodology, the study identifies recurring leadership dimensions through open coding, thematic categorization, and frequency analysis. The findings are further compared to the Full Range Leadership Theory (FRLT), widely regarded as one of the most influential and widely applied frameworks in leadership research, in order to examine the extent to which the empirical findings align with or extend beyond these established frameworks. The findings show that leadership evaluations consistently emphasize dimensions related to vision and inspiration, relational leadership, empowerment and development, communication, authenticity and values, team and culture building, and leadership balance. While many of the recurring leadership dimensions aligned with FRLT, several important aspects extended beyond the traditional framework and some leadership aspects were found to be more dominating than others. In particular, students repeatedly emphasized coaching, delegation, societal purpose, psychological safety, availability, relational closeness, and developmental support, regardless of whether they explicitly used FRLT-related frameworks or alternative leadership theories. The findings also demonstrate that leadership dimensions were used both as positive and negative justifications, highlighting tensions between empowering and controlling leadership practices. The study contributes to leadership research by showing that while FRLT captures several leadership behaviors broadly associated with effective leadership, important relational and developmental dimensions as well as the dominance and tensions between dimensions remain underrepresented within the traditional framework. The findings therefore support previous critiques questioning whether FRLT can truly be considered a “full-range” theory of leadership and suggest that leadership evaluations in practice involve a broader set of dimensions than those explicitly represented in the model.

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  Implementing medical devices in low- and middle-income countries

  (2026) Quist, Maja; Andersson Pitkänen, Linn

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  Stroke is a leading cause of death and disability globally, with a particularly heavy burden falling on low- and middle-income countries (LMICs). Despite the existence of diagnostic innovations that could improve stroke care, a persistent implementa- tion gap prevents many evidence-based technologies from reaching routine clinical use. This study examines the enabling and hampering conditions for implement- ing medical devices in stroke diagnostic processes in LMICs, using the Strokefinder MD100 in the Western Cape, South Africa as the empirical case. The study is conducted prior to implementation and applies the Consolidated Frame- work for Implementation Research (CFIR) as its primary analytical lens, comple- mented by change management theory. Data is collected through a case study de- sign, combining three qualitative methods: interviews, observation, and document study. The findings show that the Western Cape healthcare system operates under sig- nificant structural strain, shaped by resource constraints, and a fragmented stroke pathway in which most patients fall outside the treatment window. Within this con- text, Strokefinder MD100 is identified as most applicable in the early stages of the pathway, where it could support faster triage and more targeted referral decisions. Twelve conditions are identified across CFIR’s five domains as influencing imple- mentation, each capable of functioning as either enabling or hampering depending on how it is managed. Based on the findings, the study proposes a framework that differentiates imple- mentation implications along two dimensions, enabling versus hampering, and static versus dynamic, where static conditions are fixed and must be designed around, while dynamic conditions can be actively influenced. This yields four categories, each car- rying different implications for action. Furthermore, sustainability is identified as a cross-cutting condition not adequately captured within CFIR’s existing domains, and is proposed as an additional construct of particular relevance in LMIC contexts.

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  From Information Delivery to Patient Understanding

  (2026) Chung, Sally; Johansson, Elin

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  Patient information in fertility care is central to how patients understand, navigate and participate in their treatment. Despite this, information practices in IVF care remain understudied from a human-centered design perspective. This study investigates how patient information is currently created, communicated and experienced across the IVF care pathway at the Reproductive Medicine Division at Sahlgrenska University Hospital, and identifies challenges and breakdowns in the Current information flow. The study was conducted in parallel with an ongoing innovation initiative, and draws on design thinking as its methodological foundation. Data was collected through thirteen semi-structured interviews with patients and healthcare professionals, a micro-ethnographic orientation including a stimulated patient journey and clinical observations, a participatory session with staff, and complementary sources including quantitative patient satisfaction data, social media and website review. The findings show that patient information is distributed across a fragmented multichannel landscape without a shared structure for ensuring continuity across the care pathway. Information is often available in technical sense but not always accessible, timely or emotionally aligned with patient’s capacity to receive it. Breakdowns in the information flow emerge at the intersection of emotional overwhelm, structural misalignment and inequitable access. Further finding concerns the consistent exclusion of partners from the information process, despite the system formally recognizing the couple as a unit of care. The study concludes that meaningful improvement in patient information practices require not only clearer content or better communication, but a systematic commitment to designing the information environment around the patient journey. The findings contribute to an understanding of how information practices in IVF care are shaped by organizational and structural conditions, and lay groundwork for the next phase of the ongoing innovation initiative.

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